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  • 101.
    Bergman, Martin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Wiklund, Christer
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Differences in mate location behaviours between residents and nonresidents in a territorial butterfly2009Ingår i: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, ISSN 0003-3472, Vol. 78, nr 5, s. 1161-1167Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mate location strategies vary between species. Among butterflies two strategies are recognized: 'patrolling' males spend their life on the wing searching for females and 'perching' males stay at a specific site waiting to intercept passing females. In the speckled wood butterfly, Pararge aegeria, two alternative male strategies have been described: dominant males adopt a perching strategy monopolizing large sunspots on the forest floor, and subdominant males adopt a patrolling strategy. However, comparative analyses have shown that body design differs between perching and patrolling species, hence constraining opportunity for within-species variation in mate location strategy. We tested whether males differ in their propensity to adopt perching or patrolling behaviour by recording time spent flying during 30 min when alone in a large cage with only one large sunspot and many smaller ones, and whether subdominant males adopt a patrolling strategy by allowing dyads of males to interact in the cage for 60 min and recording the same behaviours again. All males adopted perching behaviour when alone, and subdominant males in dyads spent only a short time in extended flights after losing contests over territory ownership, soon returning to a perching strategy and making the best of a bad job from the vantage point of a small sunspot. We argue that previous descriptions of subdominant male P. aegeria adopting a patrolling strategy are based on too short observation periods, and have mistaken males in temporary transit for males adopting patrolling behaviour.

  • 102.
    Bergman, Martin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Wiklund, Christer
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Visual mate detection and mate flight pursuit in relation to sunspot size in a woodland territorial butterfly2009Ingår i: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, ISSN 0003-3472, Vol. 78, nr 1, s. 17-23Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Territory residency is associated with considerable benefits. In the speckled wood butterfly, Pararge aegeria, males fight over ownership of large sunspots in open forest habitats; winners become sunspot residents, and losers become nonterritorial and sit and wait for females in small sunspots. A previous study has shown that residents have higher mating success than nonterritorial males, although females are not more attracted to territorial males or sunspot territories per se. Here we tested the hypotheses (1) that the higher success of resident males is caused by visual mate detection being more efficient in a large than in a small sunspot, and (2) that only sunspots above a certain size are defended as territories. Field assessment of territorial sunspot size showed that defended sunspots were significantly larger than 'average sunspots' on the forest floor. Experimental tests of male ability to detect visually a model butterfly passing through a sunspot showed that males were more successful in pursuing and intercepting a passing model when. own a longer distance in the sunspot. Hence, we conclude that light conditions and associated visual mate detection and ability to complete mate flight pursuit can explain why P. aegeria males defend territories in large sunspots in forest habitats.

  • 103.
    Bergqvist, Claes
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Herbert, Roger
    Persson, Ingmar
    Greger, Maria
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Plants influence on arsenic availability and speciation in the rhizosphere, roots and shoots of three different vegetables2014Ingår i: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 184, s. 540-546Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The toxicity of arsenic (As) in the environment is controlled by its concentration, availability and speciation. The aims of the study were to evaluate the accumulation and speciation of As in carrot, lettuce and spinach cultivated in soils with various As concentrations and to estimate the concomitant health risks associated with the consumption of the vegetables. Arsenic concentration and speciation in plant tissues and soils was analysed by HPLC, AAS and XANES spectroscopy. To estimate the plants influence in the rhizosphere, organic acids in lettuce root exudates were analysed by ion chromatography. The results showed that the As accumulation was higher in plants cultivated in soil with higher As extractability. Arsenate predominated in the soils, rhizosphere and root exudates of lettuce. Succinic acid was the major organic acid in lettuce root exudates. Ingestion of the tested vegetables may result in an intake of elevated levels of inorganic As.

  • 104.
    Bergsten, Arvid
    Stockholms universitet, Stockholm Resilience Centre.
    Communicating ecology in local planning: The role of embedded ecologistsManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Local decision making needs to apply ecological knowledge (EK) to promote sustainable outcomes. Scientific and local EK can be incorporated by including knowledgable individuals in planning teams. This paper looks at the potential to integrate EK in planning institutions, by studying how 27 "embedded ecologists" communicate knowledge in 18 municipalities in the Stockholm region in Sweden. The analysis identifies communication patterns based on the terminology and form of EK that the surveyed ecologists prioritize in discussions with planners and politicians. The results show that maps and the meaning and direct benefit of nature to citizens are prioritized in planning discussions, since such EK can be accommodated in the current planning discourse. Knowledge regarding species and ecological complexity were more difficult to integrate, since it required simplification or translation to a citizen perspective on nature, or that the ecologist played a "communication role" that conflicted with the planning discourse. Three different communication roles are outlined, by contrasting their perspectives on EK and their likely causes and outcomes in the planning process. Recommendations are given about how governance institutions can make better use of embedded ecologists for in-house ecological knowledge.

  • 105.
    Bergsten, Arvid
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Fragmented landscapes: Assessment and communication of landscape connectivity in human-dominated landscapes2012Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This licentiate thesis summarizes the first half of my PhD on the theme of management of fragmented landscapes. The thesis applies – and reflects on the use of – network analysis of connectivity in relation to landscape planning. Relevant theory on knowledge management and spatial ecology is summarized and discussed in connection with two papers.

    Paper I centers on municipal ecologists and environmental planners in the Stockholm region. They state that connectivity is rarely considered enough in planning and that assessment tools are lacking. Paper I studies the benefits and difficulties of using network analysis to manage connectivity in land-use planning. Among the main difficulties was the choice of model species and access to input data. The main strengths were the graphical and quantitative results, the potential for social learning, identification of critical sites and to relate local planning and ecology to the regional landscape.

    Paper II applies network methodology to quantify habitat availability of fragmented lichen-type forests in protected areas in northern Sweden. It studies a dynamic landscape that is continuously rearranged by forestry, with consequences that depend on species’ abilities to compete for resources in protected habitats, and to disperse through unprotected mature forest stands. We discuss the results with reference to the planning of forestry and protected areas, and to the resilience of species to patchy disturbance regimes.

    To end I propose a continuation of research, including a methodological development of network analysis; a sociological study of the acceptance of ecological advice in urban planning; and an integration of social and ecological network analysis to compare patterns of cross-municipal collaboration with landscape connectivity.

  • 106.
    Bergsten, Arvid
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Spatial complexity and fit between ecology and management: Making sense of patterns in fragmented landscapes2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Avoiding the negative effects of habitat fragmentation on biodiversity is especially challenging when also the management institutions are spatially and administratively distributed. This doctoral thesis introduces five case studies that investigate ecological, social and social-ecological relations in fragmented landscapes. I present new approaches in which research and governance can detect and manage mismatches between landscape ecology and planning. The case studies include urban and forested landscapes where an intense land-use is limiting the connectivity, i.e., the potential for many species to disperse between the remaining patches of habitat. Graph-theoretic (network) models are applied to map connectivity patterns and to estimate the outcome for dispersing species at the patch level and for the whole study system. In particular, the network models are applied to evaluate the spatial complexity and the potential mismatches between ecological connectivity and geographically distributed management institutions like protected areas and municipalities. Interviews with municipal ecologists complement the spatial analysis; revealing some problems and ways forward regarding the communication and integration of ecological knowledge within local spatial-planning agencies. The results also show that network models are useful to identify and communicate critical ecological and social-ecological patterns that call for management attention. I suggest some developments of network models as to include interactions between species and across governance levels. Finally, I conclude that more effort is needed for network models to materialize into ecological learning and transformation in management processes.

  • 107.
    Bergsten, Arvid
    Stockholms universitet, Stockholm Resilience Centre.
    The problem of fit in social-ecological systems: Detecting spatial mismatches between ecological 
connectivity and land management in an urban regionManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    The problem of institutional fit in social-ecological systems has been empirically documented and conceptually discussed for decades, yet there is a shortage of approaches to systematically and quantitatively examine the level of fit.  Here we address this gap focusing on spatial fit in an urban and peri-urban regional landscape. Such landscapes typically exhibit significant fragmentation of remnant habitats, which can limit critical species dispersal. This may have detrimental effects on species persistence and ecosystem functioning, if land use is planned without consideration of the spatial patterns of fragmentation. Managing habitat fragmentation is particularly challenging when the scale of fragmentation reach beyond the control of single managers, thereby requiring different actors to coordinate their activities to address the problem at the appropriate scale.We present a research approach that maps patterns of collaborations between actors who manage different parts of a landscape, and then relates these patterns to potential dispersal patterns. We apply our approach to evaluate the fit between a collaborative wetland-management network comprising all 26 municipalities in the Stockholm County in Sweden, with an ecologically defined network of dispersed but ecologically interconnected wetlands. Many wetlands in this landscape are either intersected by the boundary between two or more municipalities, or located close to such boundaries, which implies a degree of ecological interconnectedness and a need for inter-municipal coordination related to wetland management across boundaries. We first estimate the level of ecological connectivity between wetlands in neighboring municipalities, and then use this estimate to elaborate the level of social-ecological fit vis-à-vis inter-municipal collaboration. We find that the level of fit is generally weak. Also, we identify critical misalignments of ecological connectivity and inter-municipal collaboration, respectively, as well as collaborations that represent an adequate alignment. These findings inform on where to most effectively allocate limited resources of collaborative capacity to enhance the level of social-ecological fit.  Our approach and results are graphically illustrated using maps, which facilitates the potential application of this method in land-use planning practice.

  • 108.
    Bergsten, Arvid
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Bodin, Örjan
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Ecke, Frauke
    Protected areas in a landscape dominated by logging - A connectivity analysis that integrates varying protection levels with competition-colonization tradeoffs2013Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 160, s. 279-288Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Conservation planning is challenging in landscapes where reoccurring habitat destruction and subsequent recovery affect metapopulation persistence, because different species respond differently to landscape change. By building on a graph-theoretical modeling framework, we here develop a connectivity model of how varying levels of area protection and unprotected areas predetermined for destruction affect species differently depending on (1) their tradeoff in colonization versus habitat utilization ability and (2) their maximum dispersal ability. We apply our model to 20,000 patches of old pine forest in northern Sweden, which host many threatened species but are scattered in a landscape dominated by intensive forestry. Unprotected mature forests stands predestined for logging are treated as adequate but temporarily available habitat for colonization specialists, whereas the same stands are assumed to, at best, serve only as intermediate stepping-stones for habitat specialists as they disperse between long-standing forests in protected areas. Our results show that the effect of habitat fragmentation on metapopulation persistence differs greatly not only depending on the dispersal distance of a particular species, but also on how well it utilizes habitat patches of different longevity. Such traits are discussed with respect to the spatiotemporal planning of habitat protection. Also, we suggest that the negative impacts of logging on biodiversity may be reduced if forestry practice is adjusted to better account for the ecological values of maturing production stands, through spatially explicit modeling of connectivity and of complementarity in the protection gradient.

  • 109.
    Bergsten, Arvid
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Zetterberg, Andreas
    To model the landscape as a network: A practitioner's perspective2013Ingår i: Landscape and Urban Planning, ISSN 0169-2046, E-ISSN 1872-6062, Vol. 119, s. 35-43Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent years have shown a rapid increase in the number of published studies that advocate network analysis (graph theory) to ecologically manage landscapes that suffer from fragmentation and loss of connectivity. This paper studies the reasons, benefits and difficulties of using network analysis to manage landscape fragmentation in the practice of land-use planning. The results are based on interviews with thirteen municipal ecologists and environmental planners in Stockholm, Sweden, who had been introduced to a GIS-tool for network-based connectivity analysis. Our results indicate that fragmentation is not considered enough in municipal planning and demonstrate that none of the interviewed practitioners used systematic methods to assess landscape connectivity. The practitioners anticipate that network-level and patch-level connectivity measures and maps would help them to communicate the meaning and implications of connectivity to other actors in the planning process, and to better assess the importance of certain habitats affected by detailed plans. The main difficulties of implementing network-based connectivity analyses reported by the respondents related to the choice of focal species and the lack of model input in terms of landscape data and dispersal distances. The main strengths were expressed by the practitioners as graphical, quantitative and credible results; the ability to compare planning alternatives and to find critical sites in a more objective manner than today; and to relate local planning and ecology to the regional structure of the landscape. Many respondents stressed the role of fragmentation assessments in the endeavor to overcome current spatial mismatches of ecological and administrative scales.

  • 110.
    Bergström, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Oviposition strategies in butterflies and consequences for conservation2005Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Oviposition strategies are an important component of life history evolution in insects. Oviposition is a complex behaviour, where females must locate suitable habitat patches, locate oviposition sites, evaluate the quality, and finally decide how many eggs to lay. In this thesis, I explore some factors that may influence oviposition strategies in female butterflies. It discusses oviposition strategies from large to fine scales and ends with a discussion on implications for conservation. In paper I we tested for local adaptations in oviposition preference and larval performance in Polyommatus icarus. The result suggests that this species is evolutionary conservative in its utilization of the tested host plants. In the second paper we investigated frequency-dependent host plant choice in Polygonia c-album and showed that females spent significantly more time, and laid more eggs, in patches with high frequency of the preferred host. The influence of nectar sources on host plant choice in P. icarus was tested in paper III, females preferred ovipositing on host plants with flowers and after feeding. In paper IV we investigated oviposition “mistakes” in P. c-album and found differences in discrimination of hosts and non-hosts. Further, we showed that P. c-album butterflies are capable of responding to host quality by increasing clutch sizes on a high ranked host (paper V). Finally, in paper VI I explored how female oviposition behaviour can influence habitat management for a threatened butterfly species, Parnassius mnemosyne, by doing an observational field study on oviposition site preferences. This thesis highlights oviposition as a stepwise process and show that female discrimination is important at a multitude of levels with implications for oviposition strategies.

  • 111.
    Bergström, Jonas
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    The evolution of mating rates in Pieris napi2004Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In the green-veined white butterfly (Pieris napi), females obtain direct fitness benefits from mating multiply and studies have shown that fitness increases seemingly monotonically with number of matings. The reason is that at mating males transfer a large nutritious gift (a so called nuptial gift) to the females that the females use to increase both their fecundity and lifespan. In addition, if exposed to poor food conditions as larvae, females mature at a smaller size compared to males. Accordingly, it was suggested that smaller females could compensate for their size through nuptial feeding by, for instance, mating more frequently. We did not find any support for that hypothesis. On the contrary, larger females remated sooner and had a higher lifetime number of matings. Neither were smaller females able to compensate in any other way, because singly mated females and multiply mated females suffered to the same extent from their smaller size. This thesis also shows that despite the positive relationship between fitness and number of matings, there is a large variation in female mating frequency in wild populations and about every second female mates only once or twice. This variation is not dependent on how often females get courted by males, because female mating frequency was shown not to be affected by male courtship intensity. Hence, the reason for the low mating frequency could either be that males have evolved the ability to manipulate females to mate at a suboptimal rate as a measure of protection against sperm competition, or alternatively, that female mating rate is suppressed by some costs. Using two selection lines, artificially selected for either a high or a low mating rate, we showed that the variation in mating rate was mainly a female trait because which line the females were from affected their mating rate whereas which line the male was from did not. This implies that females mate at a low rate due to hidden costs or due to constraints. The same study also showed that females with a high "intrinsic" mating rate lived shorter, but only when denied remating. This led us to test the hypothesis that the cost females face is to have the ability to mate at a high rate but the cost is only paid when remating opportunities are scarce. However, we found no support for such an idea, because females with a high intrinsic mating rate held in a cold environment where the butterflies were prevented from flying and feeding did not live shorter. Neither was there an effect of a female’s mating rate on her ability to quickly break down and convert male nutrient gifts into egg material. Female mating rate did, on the other hand, affect dispersal tendency, with low mating rate females being more inclined to fly between different habitats. The underlying reason for this is still to be explored.

  • 112. Bergström, Lena
    et al.
    Kautsky, Lena
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholms universitets Östersjöcentrum.
    Malm, Torleif
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholms universitets Östersjöcentrum.
    Rosenberg, Rutger
    Wahlberg, Magnus
    Capetillo, Nastassja Åstrand
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholms universitets Östersjöcentrum.
    Wilhelmsson, Dan
    Effects of offshore wind farms on marine wildlife-a generalized impact assessment2014Ingår i: Environmental Research Letters, ISSN 1748-9326, E-ISSN 1748-9326, Vol. 9, nr 3, s. 034012-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Marine management plans over the world express high expectations to the development of offshore wind energy. This would obviously contribute to renewable energy production, but potential conflicts with other usages of the marine landscape, as well as conservation interests, are evident. The present study synthesizes the current state of understanding on the effects of offshore wind farms on marine wildlife, in order to identify general versus local conclusions in published studies. The results were translated into a generalized impact assessment for coastal waters in Sweden, which covers a range of salinity conditions from marine to nearly fresh waters. Hence, the conclusions are potentially applicable to marine planning situations in various aquatic ecosystems. The assessment considered impact with respect to temporal and spatial extent of the pressure, effect within each ecosystem component, and level of certainty. Research on the environmental effects of offshore wind farms has gone through a rapid maturation and learning process, with the bulk of knowledge being developed within the past ten years. The studies showed a high level of consensus with respect to the construction phase, indicating that potential impacts on marine life should be carefully considered in marine spatial planning. Potential impacts during the operational phase were more locally variable, and could be either negative or positive depending on biological conditions as well as prevailing management goals. There was paucity in studies on cumulative impacts and long-term effects on the food web, as well as on combined effects with other human activities, such as the fisheries. These aspects remain key open issues for a sustainable marine spatial planning.

  • 113.
    Bergström, Lena
    et al.
    Fiskeriverket.
    Lagenfelt, Ingvar
    Fiskeriverket.
    Sundqvist, Frida
    Fiskeriverket.
    Andersson, Mathias H
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för zoologisk ekologi.
    Fiskeriundersökning vid Lillgrund: Kontrollprogram för Lillgrunds vindkraftspark2008Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Regeringen gav 2001 tillstånd till uppförande av en vindkraftpark på Lillgrund i Öresund. Underökningarna i det uppföljningsprogram för eventuella effekter på fisk och fiske som tagits fram, omfattar både en period före anläggandet av vindkraftparken och tre år efter idrifttagandet. Programmets provfisken och datainsamling startade med en baslinjestudie under åren 2002 till 2005. Lillgrunds vindkraftpark, med 48 vindkraftverk, togs i full drift i början av år 2008. I föreliggande rapport presenteras de undersökningar som utförts under parkens första driftsår, samt hur dessa förhåller sig till undersökningsresultaten perioden före vindkraftparkens etablering. Utförandet är integrerat med forskningsprogrammet Vindval som finansieras via Naturvårdsverket. Både bentisk och pelagisk fisk ingår i undersökningarna liksom fiskvandring.

  • 114.
    Bergvall, Ulrika Alm
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi.
    Balogh, Alexandra C.V.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi.
    Consummatory simultaneous positive and negative contrast in fallow deer: implications for selectivity2009Ingår i: Mammalian Biology, ISSN 1616-5047, E-ISSN 1618-1476, Vol. 74, nr 3, s. 236-239Artikel i tidskrift (Refereegranskat)
  • 115.
    Berkström, Charlotte
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Ecological connectivity in East African seascapes2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Coral reefs, seagrass beds and mangroves constitute a complex mosaic of habitats referred to as the tropical seascape. Great gaps exist in the knowledge of how these systems are interconnected. This thesis sets out to examine ecological connectivity, i.e. the connectedness of ecological processes across multiple scales, in Zanzibar and Mafia Island, Tanzania. Paper I examined the current knowledge of interlinkages and their effect on seascape functioning, revealing that there are surprisingly few studies on the influences of cross-habitat interactions and food-web ecology. Furthermore, 50% of all fish species use more than one habitat and 18% of all coral reef fish species use mangrove or seagrass beds as juvenile habitat in Zanzibar. Paper II examined the seascape of Menai Bay, Zanzibar using a landscape ecology approach and studied the relationship between fish and landscape variables. The amount of seagrass within 750m of a coral reef site was correlated with increased invertebrate feeder/piscivore fish abundance, especially Lethrinidae and Lutjanidae, which are known to perform ontogenetic and feeding migrations. Within patch seagrass cover was correlated with nursery species abundance. Paper III focused on a seagrass-dominated seascape in Chwaka Bay, Zanzibar and showed that small-scale habitat complexity (shoot height and density) as well as large-scale variables such as distance to coral reefs affected abundance and distribution of a common seagrass parrotfish Leptoscarus vaigiensis. Paper IV studied the connectivity and functional role of two snappers (Lutjanus fulviflamma and L. ehrenbergii) using stable isotopes (δ15N and δ13C) and found that connectivity between habitats was maintained by ontogenetic and foraging migrations by these species. The thesis concludes that ecological connectivity and multi-habitat usage by fish is a general and important characteristic in the Western Indian Ocean and should be considered in management planning.

  • 116.
    Berkström, Charlotte
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Gullström, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Lindborg, Regina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK). Stockholms universitet, Stockholm Resilience Centre.
    Mwandya, Augustine W.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Yahya, Saleh A. S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Kautsky, Nils
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Nyström, Magnus
    Stockholms universitet, Stockholm Resilience Centre.
    Exploring 'knowns' and 'unknowns' in tropical seascape connectivity with insights from East African coral reefs2012Ingår i: Estuarine, Coastal and Shelf Science, ISSN 0272-7714, E-ISSN 1096-0015, Vol. 107, s. 1-21Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Applying a broader landscape perspective to understand spatio-temporal changes in local populations and communities has been increasingly used in terrestrial systems to study effects of human impact and land use change. With today’s major declines in fishery stocks and rapid degradation of natural coastal habitats, the understanding of habitat configuration and connectivity over relevant temporal and spatial scales is critical for conservation and fisheries management of the seascape. Coral reefs, seagrass beds and mangroves are key-components of the tropical seascape. The spatial distribution of these habitat-types may have strong influences on cross-habitat migration and connectivity patterns among organisms. However, the consequences of seascape fragmentation and ecological connectivity are largely unknown. Here, we review the literature to provide an overview of current knowledge with regards to connectivity and food-web interactions within the tropical seascape. We show that information on fish acting as mobile links and being part of nutrient transfer and trophic interactions is scarce. We continue by making an in-depth analysis of the seascape around Zanzibar (Eastern Africa) to fill some of the knowledge gaps identified by the literature survey. Our analysis shows that (i) fifty percent of all fish species found within the Zanzibar seascape use two or multiple habitat-types, (ii) eighteen percent of all coral reef-associated fish species use mangrove and seagrass beds as juvenile habitat, and (iii) macrocarnivores and herbivores are highly represented among those coral reef fish species that use mangrove and seagrass beds as juvenile habitat. We argue that understanding the inter-linkages within and between habitat-types is essential for successful management of the tropical seascape.

  • 117.
    Berkström, Charlotte
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Jones, Geoffrey P.
    McCormick, Mark I.
    Trade-offs in the ecological versatility of juvenile wrasses: An experimental evaluation2014Ingår i: Journal of Experimental Marine Biology and Ecology, ISSN 0022-0981, E-ISSN 1879-1697, Vol. 453, s. 91-97Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A number of theories have been advanced to explain the evolution of specialists and generalists and how they coexist. According to trade-off theory, a species can improve performance by specialising on one habitat but does so at a cost of reduced performance in others. Specialists will outperform generalists in their preferred habitats but will be outperformed by generalists in other habitats. This study aimed to examine trade-offs in juvenile coral reef wrasses that vary in their degree to which they are specialised on microhabitats. We predicted that specialists would exhibit highest survival and growth on preferred habitats, and in contrast, generalists would tend to do equally well on all habitats. Furthermore, we predicted that specialists would outperform generalists on their preferred habitat, while generalists would outperform specialists on less preferred habitats. The predictions were tested by transplanting juveniles from four different species (two specialists, and two generalists) to patch reefs constructed from different kinds of microhabitats (live coral, dead coral, and rubble) and measuring growth and survival after 3 weeks in Kimbe Bay, Papua New Guinea. Prior to this, the degree of specialisation was assessed using resource selection ratio-based field observations of habitat use and availability. Results provided mixed evidence for the trade-off hypothesis. Specialists conformed to predictions, while generalists did not. Specialist species showed higher survival rate on their preferred habitat than generalist species and the mean growth was significantly higher on the preferred habitat than less preferred habitats for one specialist species. However, generalist species did not survive on all reefs, regardless of microhabitat Growth rates between habitats could therefore not be compared for generalists and the presence of a trade-off in fitness expressed in growth may have been missed for these species. It is thus premature to reject the trade-off theory, and we encourage examining a greater range of specialist and generalist species, under conditions in which the fate of all individuals can be more accurately determined.

  • 118.
    Berkström, Charlotte
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Jones, Geoffrey P.
    McCormick, Mark I.
    Srinivasan, Maya
    Ecological versatility and its importance for the distribution and abundance of coral reef wrasses2012Ingår i: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 461, s. 151-163Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ecological versatility, the degree to which organisms fully exploit the available resources, is an important component of ecological and evolutionary theory. However, patterns and consequences of versatility in coral reef fish have received little attention. Using a comparative approach, this study tested the consequences of ecological versatility on the distribution and abundance of juvenile wrasses (family: Labridae) in Kimbe Bay, Papua New Guinea. Resource use was examined along 4 different resource axes (horizontal distribution or reef zone, vertical distribution or depth, microhabitat and diet). Stepwise multiple regressions were used to test for relationships between niche breadth and patterns of abundance and distribution. Most exhibited a degree of apparent specialisation on at least one resource, but none were specialised along all resource axes. In terms of juvenile diet, the majority of species exhibited a high reliance on harpacticoid copepods. Microhabitat specialisation was associated with low local abundance and narrow distribution among depth zones. However, diet and macrohabitat specialisation were poor predictors of local abundance, and no relationships between local abundance, and local and regional distribution were observed. We conclude that the relationship between versatility and abundance/distribution is dependent on the resource in question. A greater understanding of the degree of ecological versatility in relation to different resources is necessary to predict how reef fishes will respond to escalating human impacts on coral reefs.

  • 119.
    Berkström, Charlotte
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Jörgensen, Tove Lund
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Hellström, Micaela
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Ecological connectivity and niche differentiation between two closely related fish species in the mangrove−seagrass−coral reef continuum2013Ingår i: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 477, s. 201-215Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We aim to understand ontogenetic shifts in habitat use and feeding patterns by 2 fish species, Lutjanus fulviflamma and L. ehrenbergii, within a tropical seascape in East Africa. Stomach contents and stable isotope signatures of muscle tissues (δ13C and δ15N) were compared between and within species. Fish of all life stages and potential food items were sampled from mangrove creeks, seagrass beds, and coral reefs around Mafia Island, Tanzania. Due to similarities in morphology between species, correct species identity was confirmed using genetic barcoding (mtDNA, partial sequence of cytochrome oxidase subunit I [COI]). Stable isotope analysis in R  (based on mixing models) confirmed that δ13C and δ15N values in L. fulviflamma and L. ehrenbergii reflected those of prey items caught in different habitats. Diets and mean δ13C and δ15N values of muscle tissue differed between life stages of fish, indicating ontogenetic changes in habitat and diet. L. fulviflamma and L. ehrenbergii differed in diet and δ13C and δ15N values of muscle tissue, although they overlapped in habitat use, suggesting food resource partitioning between the 2 species. Furthermore, diet overlap indexes were low between subadult species in mangrove and seagrass or coral habitats. L. fulviflamma displayed a diet shift with decreasing importance of small crustaceans in juveniles and an increasing importance of prey fishes in subadults and adults. L. ehrenbergii showed the opposite pattern. The study verifies feeding interlinkage within the mangrove-seagrass-coral reef continuum in Mafia Island by providing strong evidence of ontogenetic migration. Understanding these connections will enhance our ability to manage tropical seascapes, and highlights the need to include multiple habitats in marine protected areas.

  • 120.
    Berkström, Charlotte
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Lindborg, Regina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Thyresson, Matilda
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Gullström, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Assessing connectivity in a tropical embayment: Fish migrations and seascape ecology2013Ingår i: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 166, s. 43-53Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Seascape connectivity and configuration of multiple habitats are important features to include in marine spatial planning, and protecting seascapes with high connectivity is recommended. The present study examines the potential connectivity of reef fish assemblages in a shallow-water conservation area in Zanzibar (Tanzania) by analysing relationships between a set of habitat variables and fish diversity and density for different functional groups (based on diet) and life stages of fish using PLS-analysis. We combined spatial pattern metrics (habitat type, patch size, distance to patch) and dispersal abilities of a number of fish species using buffer radius to answer the questions; (i) do coral reefs with high connectivity to seagrass habitats have higher abundances and higher species richness of fish that undertake routine migrations during their life-history? and (ii) do coral reefs closer to mangrove forest support higher abundances of nursery species (i.e., fish species that use mangrove and seagrass beds as juvenile habitat)? Habitat mosaics surrounding fish survey sites and within-patch measurements inside fish survey sites were quantified at multiple scales (meters to kilometers) using aerial photography and scuba. Fish data was collected using a standardized point census method. We found that both fine- and broad-scale variables were important in structuring fish communities and connectivity with surrounding habitats, where predominantly seagrass beds within a 750 m radius had a positive influence on fish abundances of invertebrate feeders/piscivores (especially for lutjanids and lethrinids). Additionally, fine-scale seagrass cover had a positive influence on nursery species. Depth also had a positive influence on total species richness and the abundance of invertebrate feeders/piscivores. This study highlights the importance of combining connectivity and habitat configuration at different scales to fully understand and manage the tropical seascape.

  • 121.
    Berkström, Charlotte
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Lindborg, Regina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Thyresson, Matilda
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Gullström, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Seascape configuration influences connectivity of reef fish assemblagesManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Shallow-water habitats within tropical seascapes are intimately connected through ontogenetic and/or feeding migrations of fish. Knowledge on connectivity in the Indo-Pacific region is however sparse. Landscape ecology has been suggested as a useful approach when studying seascape connectivity. In this study, we examine the influence of habitat connectivity on reef fish assemblages in shallow-water habitats surrounding Zanzibar (Tanzania), using a seascape approach. We tested the relationships between a set of landscape and habitat variables and fish diversity and density for different functional groups and life stages. Habitat data was collected at scales ranging from 1m to >2km using aerial photography and ground-truthing. Fish data was collected using a standardised point census method. Furthermore, semi-structured interviews with 127 fishers in the bay were conducted to account for different fishing activity. We show that coral reefs in a complex seascape of Zanzibar are connected to seagrass beds through migration of fish. Habitat connectivity of seagrass and seagrass/coral mix within a 750m radius of coral reefs had a positive influence on fish abundances in the functional group of invertebrate feeders/piscivores, especially within the family Lutjanidae and Lethrinidae. Within-patch seagrass cover had a positive influence on nursery species. Depth also had a positive influence on fish assemblages, highlighting the importance of considering a third dimension, not accounted for in terrestrial studies. Generally, fishing activity between sites did neither influence species richness nor abundance, except for the abundance of juvenile parrotfish. We demonstrate that a landscape ecology approach, combining connectivity and habitat variables, is important for understanding and managing the tropical seascape, although it must be applied at relevant scales, habitat metrics and seascape configurations to fully capture ecological connectivity.

  • 122.
    Berzins, Arnis
    et al.
    University of Daugavpils.
    Krama, Tatjana
    University of Daugavpils.
    Krams, Indrikis
    University of Turku.
    Freeberg, Todd
    University of Tennessee.
    Kivleniece, Inese
    University of Daugavpils.
    Kullberg, Cecilia
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi.
    Rantala, Markus J
    University of Turku.
    Mobbing as a tradeoff between safety and reproduction in a songbird2010Ingår i: Behavioral Ecology, ISSN 1045-2249, E-ISSN 1465-7279, Vol. 21, nr 5, s. 1054-1060Artikel i tidskrift (Refereegranskat)
  • 123. Bidleman, Terry F.
    et al.
    Kurt-Karakus, Perihan B.
    Wong, Fiona
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Alegria, Henry A.
    Jantunen, Liisa M.
    Hung, Hayley
    Is There Still New DDT in North America?: An Investigation Using Proportions of DDT Compounds2013Ingår i: Occurrence, fate and impact of atmospheric pollutants on environmental and human health / [ed] McConnell, LL; Dachs, J; Hapeman, CJ, American Chemical Society (ACS), 2013, s. 153-181Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Usage of DDT ceased over four decades ago in Canada and the United States, and since 2000 in Mexico. Potential sources in the North American atmosphere today include emissions of legacy residues from soils and long-range transport from other countries where DDT is still used or recently banned. Distinction of source types is investigated here using proportions of p,p'-DDT, o,p'-DDT, p,p'-DDE and p,p'-DDD. The relative volatilization of DDT compounds can be accurately described by their subcooled liquid vapor pressures (PO; e.g., (p,p'-DDT/p,p'-DDE)AIR = (p,p'-DDT/p,p'-DDE)son. x PL, (DDT)/P-L,P-DDE. Using this model, the expected proportions in air due to volatilization from technical DDT and from soils in Canada, the U.S.A. and Mexico were estimated and expressed as the fractions F-DDTE = p,p'-DDT/(p,p'-DDT + P,P'-DDE), F-DDTO = p,p1-DDT/(p,p'-DDT + o,p'-DDT), and FDDTD = p,p1-DDT/(p,p'-DDT + p,p1-DDD). FDDTE, FDDTO and FDDTD predicted from soil emissions were compared to compound fractions in ambient air sampled at the Integrated Atmospheric Deposition Network (IADN) of stations on the Great Lakes between Canada and the U.S.A., and at arctic monitoring stations. FDDTE in air at IADN stations on lakes Erie, Ontario, Michigan and Huron were lower than in technical DDT vapor. This is consistent with emissions of aged residues from agricultural land and urban centers near these lakes. By comparison, FDDTE values were higher at stations on Lake Superior where atmospheric DDT is likely due to long-range transport rather than regional soil emissions. FDDTE increased from the early 1990s to 2005 at the Lake Superior stations and at the Canadian arctic station Alert between 2002-2005, whereas a significant decline in FDDTE was observed at the Norwegian arctic station Zeppelin Mountain. The mean FDDTO in air at IADN stations were consistent with either soil emissions or technical DDT composition, but annual values showed significant downward trends at two Canadian stations, and also decreased with time at Zeppelin Mountain (but not at Alert). These trends might signify contribution from dicofol-type DDT sources, which have a lower FDDTO than technical DDT or soil emissions, or preferential degradation of p,p'-DDT vs. o,p'-DDT over time. FDDTD in air at IADN stations were lower than in technical DDT vapor, showing the influence of soil sources. The enantiomer proportions of the chiral compounds o,p'-DDT and o,p1-DDD were nonracemic in some soils and ambient air, but enantiospecific analysis has not been done for IADN air samples. It is suggested that isomer, parent/metabolite and enantiomer composition information be incorporated into air monitoring programs to help identify sources.

  • 124. Biermann, Frank
    et al.
    Abbott, Kenneth
    Andresen, Steinar
    Backstrand, Karin
    Bernstein, Steven
    Betsill, Michele M.
    Bulkeley, Harriet
    Cashore, Benjamin
    Clapp, Jennifer
    Folke, Carl
    Stockholms universitet, Stockholm Resilience Centre.
    Gupta, Aarti
    Gupta, Joyeeta
    Haas, Peter M.
    Jordan, Andrew
    Kanie, Norichika
    Kluvankova-Oravska, Tatiana
    Lebel, Louis
    Liverman, Diana
    Meadowcroft, James
    Mitchell, Ronald B.
    Newell, Peter
    Oberthur, Sebastian
    Olsson, Lennart
    Pattberg, Philipp
    Sanchez-Rodriguez, Roberto
    Schroeder, Heike
    Underdal, Arild
    Vieira, Susana Camargo
    Vogel, Coleen
    Young, Oran R.
    Brock, Andrea
    Zondervan, Ruben
    Transforming governance and institutions for global sustainability: key insights from the Earth System Governance Project2012Ingår i: Current Opinion in Environmental Sustainability, ISSN 1877-3435, E-ISSN 1877-3443, Vol. 4, nr 1, s. 51-60Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The current institutional framework for sustainable development is by far not strong enough to bring about the swift transformative progress that is needed. This article contends that incrementalism-the main approach since the 1972 Stockholm Conference-will not suffice to bring about societal change at the level and speed needed to mitigate and adapt to earth system transformation. Instead, the article argues that transformative structural change in global governance is needed, and that the 2012 United Nations Conference on Sustainable Development in Rio de Janeiro must turn into a major stepping stone for a much stronger institutional framework for sustainable development. The article details core areas where urgent action is required. The article is based on an extensive social science assessment conducted by 32 members of the lead faculty, scientific steering committee, and other affiliates of the Earth System Governance Project. This Project is a ten-year research initiative under the auspices of the International Human Dimensions Programme on Global Environmental Change (IHDP), which is sponsored by the International Council for Science (ICSU), the International Social Science Council (ISSC), and the United Nations University (UNU).

  • 125. Biggs, Duan
    et al.
    Biggs, Reinette (Oonsie)
    Stockholms universitet, Stockholm Resilience Centre.
    Dakos, Vasilis
    Scholes, Robert J.
    Schoon, Michael
    Are We Entering an Era of Concatenated Global Crises?2011Ingår i: Ecology & society, ISSN 1708-3087, E-ISSN 1708-3087, Vol. 16, nr 2, s. 10-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An increase in the frequency and intensity of environmental crises associated with accelerating human-induced global change is of substantial concern to policy makers. The potential impacts, especially on the poor, are exacerbated in an increasingly connected world that enables the emergence of crises that are coupled in time and space. We discuss two factors that can interact to contribute to such an increased concatenation of crises: (1) the increasing strength of global vs. local drivers of change, so that changes become increasingly synchronized; and (2) unprecedented potential for the propagation of crises, and an enhanced risk of management interventions in one region becoming drivers elsewhere, because of increased connectivity. We discuss the oil-food-financial crisis of 2007 to 2008 as an example of a concatenated crisis with origin and ultimate impacts in far removed parts of the globe. The potential for a future of concatenated shocks requires adaptations in science and governance including (a) an increased tolerance of uncertainty and surprise, (b) strengthening capacity for early detection and response to shocks, and (c) flexibility in response to enable adaptation and learning.

  • 126.
    Biggs, Reinette
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Crépin, Ann-Sophie
    Stockholms universitet, Stockholm Resilience Centre. The Beijer Institute of Ecological Economics, The Royal Swedish Academy of Sciences, Sweden.
    Engström, Gustav
    Stockholms universitet, Stockholm Resilience Centre. The Beijer Institute of Ecological Economics, The Royal Swedish Academy of Sciences, Sweden.
    Folke, Carl
    Stockholms universitet, Stockholm Resilience Centre. The Beijer Institute of Ecological Economics, The Royal Swedish Academy of Sciences, Sweden.
    Kautsky, Nils
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Walker, Brian
    Stockholms universitet, Stockholm Resilience Centre. Sustainable Ecosystems, Australia.
    General Resilience to Cope with Extreme Events2012Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 4, nr 12, s. 3248-3259Artikel i tidskrift (Refereegranskat)
    Abstract [en]

     Resilience to specified kinds of disasters is an active area of research and practice. However, rare or unprecedented disturbances that are unusually intense or extensive require a more broad-spectrum type of resilience. General resilience is the capacity of social-ecological systems to adapt or transform in response to unfamiliar, unexpected and extreme shocks. Conditions that enable general resilience include diversity, modularity, openness, reserves, feedbacks, nestedness, monitoring, leadership, and trust. Processes for building general resilience are an emerging and crucially important area of research.

  • 127.
    Biggs, Reinette Oonsie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. Stanebosch University, South Africa.
    Peterson, Gary D.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Rocha, Juan Carlos
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    The Regime Shifts Database: A Framework for Analyzing Regime Shifts in Social-Ecological SystemsManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    This paper presents the Regime Shifts Database (RSDB), a new online, open-access database that uses a novel consistent framework to systematically analyze regime shifts based on their impacts, key drivers, underlying feedbacks, and management options. The database currently contains 27 generic types of regime shifts, and over 300 specific case studies of a variety of regime shifts. These regime shifts occur across diverse types of systems and are driven by many different types of processes. Besides impacting provisioning and regulating services, our work shows that regime shifts substantially impact cultural and aesthetic ecosystem services. We found that social-ecological feedbacks are difficult to characterize and more work is needed to develop new tools and approaches to better understand social-ecological regime shifts. We hope that the database will stimulate further research on regime shifts and make available information that can be used in management, planning and assessment. 

  • 128. Björklund, Johanna
    et al.
    Araya, Hailu
    Edwards, Sue
    Goncalves, Andre
    Hook, Karin
    Lundberg, Jakob
    Stockholms universitet, Stockholm Resilience Centre.
    Medina, Charito
    Ecosystem based agriculture combining production and conservation a viable way to feed the world in the long term?2012Ingår i: Journal of Sustainable Agriculture, ISSN 1044-0046, E-ISSN 1540-7578, Vol. 36, nr 7, s. 824-855Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study analyzed examples of sustainable ecosystem-based agriculture where management methods supported livelihoods of smallholders while at the same time local ecosystem services were enhanced in Ethiopia, Brazil, and the Philippines. Participation by farmers and collective actions were found to be a crucial driving force, as local specific knowledge and learning by doing were main components of the development. Social cohesion, particularly through associations and cooperatives, and improved marketing opportunities were also important drivers. Furthermore, recognition by authorities at all levels was perceived as crucial. Effects of climate change, insecure property rights, and political instability were potential threats. The possibilities of such systems to be scaled up beyond self-sufficiency raised further questions.

  • 129.
    Björklund, Mats
    et al.
    Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University.
    Almqvist, Gustaf
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Rapid spatial genetic differentiation in an invasive species, the round goby Neogobius melanostomus in the Baltic Sea2010Ingår i: Biological Invasions, ISSN 1387-3547, E-ISSN 1573-1464, Vol. 12, nr 8, s. 2609-2618Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We analysed the pattern of genetic differentiation among six newly established (around 10 generations) sites of the round goby (Neogobius melanostomus) in the southern Baltic Sea by means of nine microsatellite loci and in total 183 individuals. All but one site were within 30 km from each other. We found statistically significant genetic differentiation in ten out of 15 comparisons after Bonferroni correction, and since the species is newly introduced this has happened in less than ten generations. The largest genetic differentiation was found between the two most divergent habitats, while sites with a similar habitat were not significantly differentiated. Estimates of gene flow (Nm) were low and ranged from 1.5 to 5.5. A large proportion of individuals were assigned to one site (Puck), suggesting that this site has acted as a source to the other sites.

  • 130. Björkman, Maria
    et al.
    Hambäck, Peter
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen. Växtekologi.
    Rämert, Birgitta
    Neighboring monocultures enhance the effect of intercropping in turnip root flies (Delia floralis).2007Ingår i: Entomologia Experimentalis et Applicata, Vol. 124, s. 319-326Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Knowledge of insect behaviour is essential for accurately interpreting studies of diversification and to develop diversified agroecosystems that have a reliable pest-suppressive effect. In this study, we investigated the egg-laying behaviour of the turnip root fly, Delia floralis (Fall.) (Diptera: Anthomyiidae), in an intercrop-monoculture system. We examined both the main effect of intercropping and the effect on oviposition in the border zone between a cabbage monoculture [Brassica oleracea L. var. capitata (Brassicaceae)] and a cabbage-red clover intercropping system [Trifolium pratense L. (Fabaceae)]. To investigate the border-effect, oviposition was measured along a transect from the border between the treatments to the centre of experimental plots. Intercropping reduced the total egg-laying of D. floralis with 42% in 2003 and 55% in 2004. In 2004, it was also found that the spatial distribution of eggs within the experimental plots was affected by distance from the adjoining treatment. The difference in egg-laying between monoculture and intercropping was most pronounced close to the border, where egg-laying was 68% lower on intercropped plants. This difference in egg numbers decreased gradually up to a distance of 3.5 m from the border, where intercropped plants had 43% fewer eggs than the corresponding monocultured plants. The reason behind this oviposition pattern is most likely that flies in intercropped plots have a higher probability of entering the monoculture if they are close to the border than if they are in the centre of a plot. When entering the monoculture, flies can pursue their egg-laying behaviour without being disrupted by the clover. As the final decision to land is visually stimulated, flies could also be attracted to fly from the intercropped plots into the monoculture, where host plants are more visually apparent. Visual cues could also hinder flies in a monoculture from entering an intercropped plot. Other possible patterns of insect attack due to differences in insect behaviour are discussed, as well as the practical application of the results of this study.

  • 131. Björkman, Maria
    et al.
    Hopkins, Richard
    Hambäck, Peter
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Rämert, Birgitta
    Effects of plant competition and herbivore density on the development of the turnip root fly (Delia floralis) in an intercropping system2009Ingår i: Arthropod-plant interactions, ISSN 1872-8855, Vol. 3, s. 55-62Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, interactive effects of plant competition and herbivory on plant quality and herbivore development were examined in a greenhouse experiment where cabbage plants [Brassica oleracea L. var. capitata (Brassicaceae)] were intercropped with red clover [Trifolium pratense L. (Fabaceae)]. Cabbages were grown with two red clover densities and attack rates by the root feeding herbivore the turnip root fly, Delia floralis Fall. (Diptera: Anthomyiidae). Above ground and below ground cabbage biomass was reduced through intercropping and larval damage. Intercropping also resulted in lower nitrogen and higher carbon root levels compared with levels in the roots of monocultured cabbage. Furthermore, both root nitrogen and carbon levels increased with herbivory. Root neutral detergent fibre (NDF) and lignin content increased in response to both increased plant competition and higher egg densities. For lignin, an interaction effect was observed in the form of elevated levels in intercropped plants subjected to larval damage, while levels in roots of monocultured cabbage remained unchanged. The quality changes brought about by clover competition affected D. floralis development negatively, which resulted in reduced pupal weight. In addition, increased egg density also decreased larval growth. The effects on the development of D. floralis in relation to host plant quality are discussed.

  • 132.
    Blandon, Abigayil
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Daw, Tim
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Haider, L. Jamila
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Stone-Jovicich, Samantha
    Conceptualisations of fisheries development in Eastern Africa over time and between actors2019Ingår i: Marine Policy, ISSN 0308-597X, E-ISSN 1872-9460, Vol. 107, artikel-id UNSP 103512Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Since the late-2000s, there has been a growing discussion around development aid approaches that reflect complexity concepts, such as adaptive and iterative project management. Fisheries development interventions deal with particularly complex realities. They also illustrate the changing problems and prescribed solutions of development paradigms over time, which have yet to be systematically analysed in a fisheries context. This study analyses documents from 11 World Bank fisheries development projects from 1975 to 2017 in Eastern Africa and interviews with 13 project designers and implementers. The conceptualisation of the fisheries development system - the perceived problems, causal links and proposed solutions - was captured in each document and interview. The documents showed a clear difference in the variables and consequential links most frequently mentioned before 1995 and after 2000, moving from a narrow sectoral approach with tangible interventions such as infrastructure, to a more holistic approach pushing for softer solutions such as stakeholder engagement. While this suggests a change in the institutional World Bank paradigm, the contemporary interviews were not necessarily consistent with this shift. Interviewees' conceptualisations also differed between each other, which may have implications for project implementation. A range of concepts related to complexity thinking were found and coded in both interviews and documents, particularly documents from recent World Bank projects. While this shows some evidence of actors and institutions incorporating complexity concepts into their narrative, concepts of adaptation, unpredictability, non-comparability and feedbacks were poorly reflected, showing the current gaps if approaches such as adaptive management are to be taken up.

  • 133.
    Blasiak, Robert
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. University of Tokyo, Japan.
    Wabnitz, Colette C. C.
    Daw, Tim
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. Stockholm Univ, SRC, Stockholm, Sweden.
    Berger, Michael
    Blandon, Abigayil
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Carneiro, Goncalo
    Crona, Beatrice
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre. The Beijer Institute of Ecological Economics, Sweden.
    Davidson, Mary Frances
    Guggisberg, Solene
    Hills, Jeremy
    Mallin, Felix
    McManus, Edmund
    Ould-Chih, Karim
    Pittman, Jeremy
    Santos, Xose
    Westlund, Lena
    Wetterstrand, Hanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Wiegler, Kai
    Towards greater transparency and coherence in funding for sustainable marine fisheries and healthy oceans2019Ingår i: Marine Policy, ISSN 0308-597X, E-ISSN 1872-9460, Vol. 107, artikel-id UNSP 103508Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This final manuscript in the special issue on Funding for ocean conservation and sustainable fisheries is the result of a dialogue aimed at connecting lead authors of the special issue manuscripts with relevant policymakers and practitioners. The dialogue took place over the course of a two-day workshop in December 2018, and this coda manuscript seeks to distil thinking around a series of key recurring topics raised throughout the workshop. These topics are collected into three broad categories, or needs: 1) a need for transparency, 2) a need for coherence, and 3) a need for improved monitoring of project impacts. While the special issue sought to collect new research into the latest trends and developments in the rapidly evolving world of funding for ocean conservation and sustainable fisheries, the insights collected during the workshop have helped to highlight remaining knowledge gaps. Therefore, each of the three needs identified within this manuscript is followed by a series of questions that the workshop participants identified as warranting further attention as part of a future research agenda. The crosscutting nature of many of the issues raised as well as the rapid pace of change that characterizes this funding landscape both pointed to a broader need for continued dialogue and study that reaches across the communities of research, policy and practice.

  • 134.
    Blomqvist, Sven
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Gunnars, A.
    Räddningsplan för Östersjön2008Ingår i: Kemivärlden Biotech med Kemisk Tidskrift, Vol. 4/2008, s. 28-30Artikel i tidskrift (Övrigt vetenskapligt)
  • 135.
    Blomqvist, Sven
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Rydin, E.
    Hur fosforbindningen i Östersjöns bottensediment kan förbättras.2009Rapport (Övrigt vetenskapligt)
  • 136. Blyh, Kerstin
    et al.
    Erikcsdotter, Siv
    Stockholms universitet, Stockholm Resilience Centre.
    Nekoro, Marmar
    Stockholms universitet, Stockholm Resilience Centre.
    Scharin, Henrik
    Stockholms universitet, Stockholm Resilience Centre.
    Hasselström, Linus
    Söderqvist, Tore
    Värdet av en friskare Östersjö2012Ingår i: Havet: om miljötillståndet i i svenska havsområden, Stockholm: Naturvårdsverket, 2012, , s. 3s. 17-19Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [sv]

    Totalt är Östersjöborna villiga att betala runt 40 miljarder kronor per år för en förbättrad havsmiljö. Det visar en ny studie där befolkningen i alla nio länder runt Östersjön tillfrågats om vad de är villiga att betala för att minska övergödningen i havet. Studien visar att det finns ett stöd hos befolkningen runt Östersjön för att satsa resurser på åtgärder.

  • 137.
    Bodin, Ö.
    et al.
    Stockholms universitet, Övriga enheter, Stockholm Resilience Centre.
    Crona, B.
    Stockholms universitet, Övriga enheter, Stockholm Resilience Centre.
    Management of Natural Resources at the community level: Exploring the role of social capital and leadership in a rural fishing community2008Ingår i: World development, Vol. 36, nr 12, s. 2763-2779Artikel i tidskrift (Refereegranskat)
  • 138.
    Bodin, Örjan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för systemekologi.
    Tengö, Maria
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Norman, Anna
    Stockholms universitet, Stockholm Resilience Centre.
    Lundberg, Jakob
    Elmqvist, Thomas
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    The value of small size: loss of forest patches and ecological thresholds in southern Madagascar2006Ingår i: Ecological Applications, ISSN 1051-0761, E-ISSN 1939-5582, Vol. 16, nr 2, s. 440-451Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many services generated by forest ecosystems provide essential support for human well-being. However, the vulnerability of these services to environmental change such as forest fragmentation are still poorly understood. We present spatial modeling of the generation of ecosystem services in a human-dominated landscape where forest habitat patches, protected by local taboos, are located in a matrix of cultivated land in southern Madagascar. Two ecosystem services dependent on the forest habitats were addressed: (1) crop pollination services by wild and semidomesticated bees (Apoidea), essential for local crop production of, for example, beans, and (2) seed dispersal services based on the presence of ring-tailed lemurs (Lemur catta). We studied the vulnerability of these ecosystem services to a plausible scenario of successive destruction of the smallest habitat patches. Our results indicate that, in spite of the fragmented nature of the landscape, the fraction of the landscape presently covered by both crop pollination and seed dispersal services is surprisingly high. It seems that the taboo system, though indirectly and unintentionally, contributes to upholding the generation of these services by protecting the forest patches. Both services are, however, predicted to be very vulnerable to the successive removal of small patches. For crop pollination, the rate of decrease in cover was significant even when only the smallest habitat patches were removed. The capacity for seed dispersal across the landscape displayed several thresholds with habitat patch removal. Our results suggest that, in order to maintain capacity for seed dispersal across the landscape and crop pollination cover in southern Androy, the geographical location of the remaining forest patches is more crucial than their size. We argue that in heavily fragmented production landscapes, small forest patches should increasingly be viewed as essential for maintaining ecosystem services, such as agricultural production, and also should be considered in the ongoing process of tripling the area of protected habitats in Madagascar.

  • 139.
    Bodin, Örjan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Österblom, Henrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    International fisheries regime effectiveness: Activities and resources of key actors in the Southern Ocean2013Ingår i: Global Environmental Change, ISSN 0959-3780, E-ISSN 1872-9495, Vol. 23, nr 5, s. 948-956Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many contemporary environmental challenges are truly global and span several organizational and geographical borders. Research on international environmental regimes has, over the last couple of decades, identified several important factors that contribute to a more effective governance of global ecological resources, but few studies have addressed the different roles certain influential individual organizations play in determining regime effectiveness. Here we address this question by studying a relatively successful fishery governance system in the Southern Ocean. By drawing on insights from the research fields of common-pool resource management and international environmental regimes, we demonstrate that organizations engaged in certain combinations of activities, and that have access to certain combinations of resources stand out as important for regime effectiveness. In particular, collaboration with other flag states and being politically well-connected stand out as important explanatory factors. However, access to advanced technology, engagement in public campaigns, and being active in the field are other factors that, in different combinations, also seem to explain organizational importance. Furthermore, governmental and non-governmental organizations tend to perform different sets of activities and possess different resources, thereby complementing each other. Also, organizations doing similar things are often of different types with different mandates and objectives. This could contribute to improved adaptability and responsiveness to change at the larger regime level. Finally, we discuss some potential implications of our results for capacity-building in international environmental governance.

  • 140.
    Bohlin, Titti
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Zoologisk ekologi.
    Tullberg, Birgitta S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Zoologisk ekologi.
    Merilaita, Sami
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Zoologisk ekologi.
    The effect of signal appearance and distance on detection risk in an aposematic butterfly larva (Parnassius apollo)2008Ingår i: Animal Behaviour, ISSN 0003-3472, Vol. 76, s. 577-584Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aposematic coloration commonly involves patterns with contrasting colours. The early larva of Parnassius

    apollo is uniformly black, but the later instars develop two rows of dorsal orange spots. We tested the effect

    of these orange markings on the conspicuousness of the last-instar larva, by manipulating larval coloration

    in photographs from a natural habitat and measuring how fast human subjects could discover the larva on

    a touch screen. In the first experiment we compared the detectability of the natural phenotype with that of

    manipulated uniformly black and uniformly orange variants at different distances. In the second experiment

    with another set of photographs we added manipulations involving enlarged and reduced spot sizes.

    Generally, detection time increased with distance, and decreased with the proportion of orange in the coloration.

    The uniformly black larvae were surprisingly hard to detect even at the closest distances, suggesting

    that the young black instar has an efficient camouflage. Furthermore, even a small amount of orange

    colour increased the conspicuousness of the larva considerably, indicating that the orange markings are

    costly in terms of detectability. Importantly, as the increase in detection time over distances was larger

    for the natural coloration than for the orange coloration, we suggest that the natural coloration may involve

    a distance-dependent switch from conspicuousness to camouflage with increasing distance. Thus,

    even though the orange markings most probably have a signalling function, the coloration is not maximized

    for either crypsis or conspicuousness.

  • 141.
    Bolmgren, Kjell
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Adaptation and Constraint in the Plant Reproductive Phase2004Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Äpplet faller inte långt från trädet. Men varför? Den biologiska mångfalden präglas i stor utsträckning av fylogenetiskt bevarade karaktärsdrag; närbesläktade arter är lika. Det pågår en diskussion bland evolutionsbiologer om i vilken utsträckning denna konservatism är ett resultat av naturlig selektion eller av en begränsad anpassningsförmåga.

    Denna avhandling diskuterar begreppet evolutionära begränsningar i relation till den reproduktiva fasen hos växter. I fokus ligger särskilt evolutionen av bärliknande (endozoochora) frukter respektive evolutionen av säsongsmässiga mönster (fenologi) för blomning och fruktsättning. Avhandlingen är hierarkiskt organiserad så att olika delstudier gjordes på olika skalnivåer: fenologi- och fruktevolution analyserades för fröväxter respektive gömfröiga växter; inom brakvedssläktena Rhamnus och Frangula (Rhamnaceae); samt för en lokal population av brakved (Frangula alnus). Populationsstudien baserades på såväl experimentella som deskriptiva data, medan övriga studier i huvudsak genomfördes med fylogenetisk komparativ metodik baserade på litteraturdata. Som en del av de komparativa studierna rekonstruerades fylogenetiska hypoteser för Rhamnus s.l. utifrån DNA-sekvenser (ITS, trnL-F), vilka gav stöd för att Frangula och Rhamnus är monofyletiska systersläkten.

    I en biogeografiskt kontrollerad fylogenetisk kontrastanalys upptäcktes inga skillnader i artrikedom mellan djur- och vindpollinerade växter. Bärliknande frukter verkar dock vara en betydelsefull karaktär (key innovation) i skogsmiljöer. För det första var fylogenetiska klader med bärliknande frukter mer artrika än systerklader med torra frukter. Dessutom var uppkomster av bärliknande frukt korrelerad till habitat med mer sluten vegetation.

    En fylogenetisk kontrastanalys av allometriska effekter visade på en positiv korrelation mellan växtindividens och fruktens storlek inom Rhamnus s.l. Upprepade analyser av dessa allometriska samband i olika monofyletiska subklader inom Rhamnus s.l. indikerar dock att allometri, såsom evolutionär begränsning, är svag. I populationsstudien av F. alnus var fruktstorlek positivt korrelerad till såväl fröantal som frövikt. En generell hypotes utifrån denna avhandling blir därför att frugivorer (de djur som äter bären och därmed sprider växtens frön) utövar ett starkt selektionstryck på växter som koloniserar ett habitat där fröstorlek är adaptivt, eftersom fruktstorlek påverkar frugivorernas (ssk. fåglars) sätt att hantera frukten.

    Reproduktiv fenologi var korrelerad till fruktsättning, fröspridning och fröstorlek hos F. alnus. Detta stödjer tanken att evolutionen av blomnings- och fruktsättningstider begränsas av avvägningar (trade-offs) och partiella beroenden mellan blomning-, fruktsättnings-, spridnings och rekryteringsfaserna. Inomartsvariation i blomningstid för F. alnus respektive getapel (Rhamnus cathartica) över en nordeuropeisk latitudinell transekt var inte korrelerad till säsongslängd, vilket antyder att utvecklingen av blomningstider är evolutionärt begränsad. Å andra sidan påvisades en sådan korrelation mellan blomningstid och säsongslängd i en mellanartsstudie inom Rhamnus s.l. Den fylogenetiska kontrastanalysen mellan djur- och vindpollinerade växter visade också på adaptiva skillnader i fenologi. Blomningstiderna inom en klad med biotiskt pollinerade arter var mer åtskilda än inom den vindpollinerade systerkladen, och den välkända iakttagelsen att vindpollinerade träd blommor tidigare på säsongen fick även stöd i ett fylogenetiskt komparativt perspektiv.

  • 142.
    Bonaglia, Stefano
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologiska vetenskaper.
    Deutsch, Barbara
    Bartoli, Marco
    Brüchert, Volker
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologiska vetenskaper.
    Seasonal benthic nutrient cycling in a Baltic sea estuary2012Ingår i: / [ed] The Oceanography Society, American Society of Limnology and Oceanography, American Geophysical Union, 2012Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Decades of urban, industrial, and agricultural discharge of nitrogen and phosphorus to the Baltic Sea have contributed to the spreading of water column hypoxia and annual widespread cyanobacteria blooms. Central to mitigating Baltic Sea eutrophication is to resolve how much reduction strategies of external N and P loading are offset by internal loading of the Baltic through nutrient recycling from the sediment. We investigated the seasonal variation of benthic nitrogen and phosphorus cycling in an estuary of the Baltic impacted by decades of sewage discharge. Sediment nutrient fluxes, denitrification, Anammox, DNRA, potential nitrification, and total and diffusive oxygen uptake (TOU/DOU) were quantified with 15N-tracer methods and microsensor profiling. Data indicate benthic net efflux of ammonium and phosphorus during the summer months, decreasing N2 loss with increasing organic matter content, and benthic N/P regeneration with a ratio of 3 to 7 compared to the sewage discharge N/P of ≈ 25, and a significant contribution (6 to 25%) of Anammox to N2 loss. On average benthic denitrification and Anammox may reduce the N load to the estuary by up to 54%.

  • 143.
    Boonstra, Wiebren J.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre, Baltic Nest Institute. University of Oslo, Norway.
    de Boer, Florianne W.
    The Historical Dynamics of Social-Ecological Traps2014Ingår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 43, nr 3, s. 260-274Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Environmental degradation is a typical unintended outcome of collective human behavior. Hardin's metaphor of the tragedy of the commons has become a conceived wisdom that captures the social dynamics leading to environmental degradation. Recently, traps has gained currency as an alternative concept to explain the rigidity of social and ecological processes that produce environmental degradation and livelihood impoverishment. The trap metaphor is, however, a great deal more complex compared to Hardin's insight. This paper takes stock of studies using the trap metaphor. It argues that the concept includes time and history in the analysis, but only as background conditions and not as a factor of causality. From a historical-sociological perspective this is remarkable since social-ecological traps are clearly path-dependent processes, which are causally produced through a conjunction of events. To prove this point the paper conceptualizes social-ecological traps as a process instead of a condition, and systematically compares history and timing in one classic and three recent studies of social-ecological traps. Based on this comparison it concludes that conjunction of social and environmental events contributes profoundly to the production of trap processes. The paper further discusses the implications of this conclusion for policy intervention and outlines how future research might generalize insights from historical-sociological studies of traps.

  • 144.
    Boonstra, Wiebren J.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre, Baltic Nest Institute.
    Joosse, Sofie
    The Social Dynamics of Degrowth2013Ingår i: Environmental Values, ISSN 0963-2719, E-ISSN 1752-7015, Vol. 22, nr 2, s. 171-189Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Degrowth cannot be realised from within a capitalist society, since growth is the sine qua non for capitalism. But, societies are no blank slates; they are not built from scratch. Putting these two thoughts together seems to make degrowth logically impossible. In this paper we argue that this paradox can be solved with the use of classical and contemporary concepts from the social sciences. We illustrate the use of these concepts with reference to studies on current practices and patterns of food production and consumption. The concept of social mechanism is used to illustrate how social practices can simultaneously reinforce and challenge the dominant (food) regime. We argue that current discussions on degrowth fail to envision how such contrasting developments are linked, and that the degrowth paradox originates in the idea of capitalism and the steady-state economy as alternative systems. The paradox dissolves with studies of mechanisms and social practices that show how the two systems are not autonomous, but 'hybridised' and come into existence and gain shape as reactions to each other.

  • 145.
    Borg, Hans
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Sundbom, Marcus
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Long-term trends of water chemistry in mountain streams in Sweden - slow recovery from acidification2014Ingår i: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 11, nr 1, s. 173-184Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The water chemistry of streams and precipitation in the province of Jamtland, northern Sweden has been monitored since the 1980s to study long-term trends, occurrence of acid episodes, and effects of liming. The acidity in precipitation increased in the 1970s, followed by a loss of acid neutralizing capacity (ANC) and low pH in the streams. Sulfur deposition began to decrease in the 1980s, until approximately 2000, after which the decrease levelled out. Stream water sulfate concentration followed the precipitation trend but decreased more slowly and since the late 1990s a subtle increase was observed. Sulfate concentrations in the snow typically have been higher than or equal to the stream sulfate levels. However, during the period of rapid deposition decrease and also since 2005 stream sulfate has sometimes exceeded snow sulfate, indicating desorption of stored soil sulfate, possibly because of climate-related changes in runoff routes through the soil profiles, following shorter periods of frost. From 1982 to 2000, total organic carbon (TOC) increased by approximately 0.1 mg L-1 yr(-1). The mean trends in sulfate and TOC from approximately 1990 until today were generally opposite. Acidic episodes with pH 4.0 at flow peaks occurred frequently in the unlimed streams, despite relatively well-buffered waters at baseflow. To evaluate the main causes for the loss of ANC during episodes, the changes in major ion concentrations during high flow episodes were evaluated. The most important factors contributing to ANC loss were dilution of base cations (Na+, K+, Ca2+, Mg2+), enrichment of organic anions and enrichment of sulfate. Wetland liming started in 1985 after which the earlier observed extreme peak values of iron, manganese and aluminium, did not reoccur. The studied area is remote from emission sources in Europe, but the critical load of acidity is still exceeded. The long-term recovery observed in the unlimed streams is thus slow, and severe acidic episodes still occur.

  • 146. Borga, Katrine
    et al.
    Fjeld, Eirik
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Consistency in Trophic Magnification Factors of Cyclic Methyl Siloxanes in Pelagic Freshwater Food Webs Leading to Brown Trout2013Ingår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, nr 24, s. 14394-14402Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cyclic volatile methyl siloxanes (cVMS) concentrations were analyzed in the pelagic food web of two Norwegian lakes (Mjosa, Randsfjorden), and in brown trout (Salmo trutta) and Arctic char (Salvelinus alpinus) collected in a reference lake (Femunden), in 2012. Lakes receiving discharge from wastewater treatment plants (Mjosa and Randsfjorden) had cVMS concentrations in trout that were up to 2 orders of magnitude higher than those in Femunden, where most samples were close to the limit of quantification (LOO). Food web biomagnification of cVMS in Mjosa and Randsfjorden was quantified by estimation of trophic magnification factors (TMFs). TMF for legacy persistent organic pollutants (POPs) were analyzed for comparison. Both decamethylcyclopentasiloxane (DS) and dodecamethylcyclohexasiloxane (D6) biomagnified with TMFs of 2.9 (2.1-4.0) and 2.3 (1.8-3.0), respectively. Octamethylcyclotetrasiloxane (D4) was below the LOQ in the majority of samples and had substantially lower biomagnification than for D5 and D6. The cVMS TMFs did not differ between the lakes, whereas the legacy POP TMFs were higher in Mjosa than inRandsfjorden. Whitefish had lower cVMS bioaccumulation compared to legacy POPs, and affected the TMF significance for cVMS, but not for POPs. TMFs of D5 and legacy contaminants in Lake Mjosa were consistent with those previously measured in Mjosa.

  • 147.
    Borgström, Sara
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Systemekologiska institutionen.
    Cousins, Sara
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Lindborg, Regina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Outside the boundary - land use changes in the surroundings of urban nature reserves2012Ingår i: Applied Geography, ISSN 0143-6228, E-ISSN 1873-7730, Vol. 32, nr 2, s. 350-359Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The importance of the landscape surrounding a protected area for sustaining its values is frequently discussed in conservation literature. Studies on the interactions of urbanisation and nature conservation at the global scale suggest that protected nature attracts urbanisation, and that this in turn might negatively impact the area. However, studies specifically addressing such land use dynamics at city scale are largely missing. In this study we examine the change in proportion of built up area in two zones (500 m and 1000 m) surrounding 15 urban nature reserves in southern Sweden. By using comprehensive maps from the last 50 years, we compared the zones to the overall urbanisation in the cities to reveal discrepancies in land use surrounding the nature reserves. We found that the amount of built up area in the buffer zones surrounding nature reserves followed the same trend as the corresponding cities and this relation was stable over time, although the positive relationship was not significant. The establishment of nature reserves had no detectable effect on surrounding land use, however two distinguished groups of reserves were identified with either more or less built up area in buffers zones compared to cities. These differences were related to specific local drivers such as land ownership, land use history and nature reserve location. In contrast to earlier studies at global scale, our study did not show that nature reserves attract urbanisation. Instead, we stress that the great variety of contextual factors at the city scale makes quantitative analysis of this kind extremely difficult. However, a general neglect from planning and nature conservation agencies to recognise nature reserves’ dependence on the surrounding landscape configuration could be detrimental to sustain their values in the long-term. Hence we suggest that zones surrounding nature-protected areas should be planned and managed according to local land use history and current landscape conditions to enable and enhance necessary cross-boundary interactions.

  • 148.
    Borgström, Sara
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Lindborg, Regina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Elmqvist, Thomas
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Nature conservation for what?: Analyses of urban and rural nature reserves in southern Sweden 1909-20062013Ingår i: Landscape and Urban Planning, ISSN 0169-2046, E-ISSN 1872-6062, Vol. 117, s. 66-80Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To effectively integrate nature conservation in sustainable landscape management, it isessential to deepen the understanding of why, what, where and for whom nature isprotected. This is especially important for nature conservation in human dominatedlandscapes such as cities, where the distance between built up and protected areas is inconstant decline due to urbanisation worldwide. In this study we use historical andcurrent data from Sweden to examine how urban compared to rural nature conservationhave been using formal nature reserve objectives. The focal nature conservationobjectives in our study area were preservation of biodiversity, restoration ofenvironments and outdoor recreation, as well as subdivision of those. The use of theseobjectives were analysed for 1869 nature reserves in relation to degree of urbanisation.We found that nature reserves in more urbanised landscapes were based on a highernumber of objectives. The urban reserves also had a different composition of objectives,where the objectives outdoor recreation and biodiversity preservation were morecommon in urban than in rural reserves. During the last decades we detected a shift inuse of objectives in urban areas, going from biodiversity preservation to a strongerfocus on outdoor recreation. National and global trends in the nature conservationdebate could also be seen as reflected in the use of objectives. To ensure its adaptivecapacity, we stress that urban nature conservation needs a more proactive strategy,where potential future social as well as ecological values must be embraced and notonly existing ones.

  • 149. Boström, Jannika E.
    et al.
    Kullberg, Cecilia
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi.
    Åkesson, Susanne
    Northern magnetic displacements trigger endogenous fuelling responses in a naive bird migrant2012Ingår i: Behavioral Ecology and Sociobiology, ISSN 0340-5443, E-ISSN 1432-0762, Vol. 66, nr 5, s. 819-821Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In a previous study, we found that juvenile northern wheatears (Oenanthe oenanthe) exposed to a magnetic displacement to the west of their natural migration route increased their body mass. The total intensity and inclination used for the western displacement may also have been interpreted as northern compared to the experimental site (stronger total field intensity and steeper inclination angle). In order to investigate whether the fuelling response was a response to an unexpected magnetic field or specific to the northern magnetic field, we conducted a new experiment. Juvenile wheatears from the same study population were magnetically displaced to southwestern magnetic fields, exposing the birds to unexpected magnetic combinations, but eliminating the possible effect of a northern magnetic field. A control group was kept in the local geomagnetic field in Sweden for comparison. There was no difference in body mass increase between treatments, suggesting that the fuelling response previously found was not a simple response to an unexpected magnetic field, but rather a specific response to the northern magnetic field. Juvenile wheatears may have developed a fuelling response to northern magnetic fields in order to enable a successful flight towards the migration goal.

  • 150. Boström, Jannika
    et al.
    Fransson, Thord
    Henshaw, Ian
    Jakobsson, Sven
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi.
    Kullberg, Cecilia
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen, Avdelningen för etologi.
    Åkesson, Susanne
    Autumn migratory fuelling: a response to simulated magnetic displacement in juvenile wheatears, Oenathe oenathe2010Ingår i: Behavioral Ecology and Sociobiology, ISSN 0340-5443, E-ISSN 1432-0762, Vol. 64, nr 11, s. 1725-1732Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent experiments exposing migratory birds to altered magnetic fields simulating geographical displacements have shown that the geomagnetic field acts as an external cue affecting migratory fuelling behaviour. This is the first study investigating fuel deposition in relation to geomagnetic cues in long-distance migrants using the western passage of the Mediterranean region. Juvenile wheatears (Oenanthe oenanthe) were exposed to a magnetically simulated autumn migration from southern Sweden to West Africa. Birds displaced parallel to the west of their natural migration route, simulating an unnatural flight over the Atlantic Ocean, increased their fuel deposition compared to birds experiencing a simulated migration along the natural route. These birds, on the other hand, showed relatively low fuel loads in agreement with earlier data on wheatears trapped during stopover. The experimental displacement to the west, corresponding to novel sites in the Atlantic Ocean, led to a simulated longer distance to the wintering area, probably explaining the observed larger fuel loads. Our data verify previous results suggesting that migratory birds use geomagnetic cues for fuelling decisions and, for the first time, show that birds, on their first migration, can use geomagnetic cues to compensate for a displacement outside their normal migratory route, by adjusting fuel deposition.

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