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  • 1.
    Dile, Yihun Taddele
    et al.
    Stockholms universitet, Stockholm Resilience Centre, Stockholm Environment Institute.
    Karlberg, Louise
    Stockholms universitet, Stockholm Resilience Centre, Stockholm Environment Institute.
    Temesgen, Melesse
    Rockström, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    The role of water harvesting to achieve sustainable agricultural intensification and resilience against water related shocks in sub-Saharan Africa2013Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 181, s. 69-79Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Poverty alleviation in rural areas is a top priority for social and economic development, particularly against a backdrop of rising populations up to 2050 and to meet growing food demands in a rapidly urbanizing world. Sustainable intensification of agricultural techniques are therefore required, such as water management practices that result in higher agricultural production without causing severe environmental impacts, whilst at the same time improving resilience to drought and dry spells. Water harvesting practices have shown promising results in reducing risks, and improving yields whilst also delivering positive impacts on other ecosystems. However, before large scale implementation of water harvesting, further investigation of local downstream impacts are warranted. We conclude that water harvesting remains a promising option for sustainable agricultural intensification in the water scarce tropics, resulting in both risk reduction and yield improvements.

  • 2.
    Eriksson, Sofia
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Skånes, Helle
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Addressing semantics and historical data heterogeneities in cross-temporal landscape change analyses2010Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 139, nr 139, s. 516-521Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The process of recreating historical land cover dynamics, needed to understand trends and transient states in ecosystems, includes difficulties such as the sensitivity of applied spatial analyses to heterogeneities in historical material. This paper compares the handling of quantitatively dominating categories in two matrix analyses of land cover change within a Swedish boreal landscape (1725–1859). The focus is on how inconsistencies between historical maps can be handled without violating the inherent semantic potential. The study shows that analyses of land cover support different indications of change depending on the treatment of dominating categories. The type of landscape and research questions in focus should therefore be part of choosing matrix method and classification scheme. The observed patterns need to be evaluated against drivers of change and semantic plasticity in classification schemes to separate ecological change from semantic confusion. This paper recommends aggregated classification schemes with maintained original relationships between categories in comprehensive analyses. However, no pathway is persistent over time and categories should be allowed to disappear and new to appear. Analysis of historical dynamics with extended transition matrixes is recommended to account for the dynamics of small categories in relation to dominating categories within a landscape.

  • 3. Happe, Anne-Kathrin
    et al.
    Alins, Georgina
    Blüthgen, Nico
    Boreux, Virginie
    Bosch, Jordi
    García, Daniel
    Hambäck, Peter A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Klein, Alexandra-Maria
    Martínez-Sastre, Rodrigo
    Miñarro, Marcos
    Müller, Ann-Kathrin
    Porcel, Mario
    Rodrigo, Anselm
    Roquer-Beni, Laura
    Samnegård, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Tasin, Marco
    Mody, Karsten
    Predatory arthropods in apple orchards across Europe: Responses to agricultural management, adjacent habitat, landscape composition and country2019Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 273, s. 141-150Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Local agri-environmental schemes, including hedgerows, flowering strips, organic management, and a landscape rich in semi-natural habitat patches, are assumed to enhance the presence of beneficial arthropods and their contribution to biological control in fruit crops. We studied the influence of local factors (orchard management and adjacent habitats) and of landscape composition on the abundance and community composition of predatory arthropods in apple orchards in three European countries. To elucidate how local and landscape factors influence natural enemy effectiveness in apple production systems, we calculated community energy use as a proxy for the communities' predation potential based on biomass and metabolic rates of predatory arthropods. Predator communities were assessed by standardised beating samples taken from apple trees in 86 orchards in Germany, Spain and Sweden. Orchard management included integrated production (IP; i.e. the reduced and targeted application of synthetic agrochemicals), and organic management practices in all three countries. Predator communities differed between management types and countries. Several groups, including beetles (Coleoptera), predatory bugs (Heteroptera), flies (Diptera) and spiders (Araneae) benefited from organic management depending on country. Woody habitat and IP supported harvestmen (Opiliones). In both IP and organic orchards we detected aversive influences of a high-quality surrounding landscape on some predator groups: for example, high covers of woody habitat reduced earwig abundances in German orchards but enhanced their abundance in Sweden, and high natural plant species richness tended to reduce predatory bug abundance in Sweden and IP orchards in Spain. We conclude that predatory arthropod communities and influences of local and landscape factors are strongly shaped by orchard management, and that the influence of management differs between countries. Our results indicate that organic management improves the living conditions for effective predator communities.

  • 4. Jara, Taye
    et al.
    Hylander, Kristoffer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Nemomissa, Sileshi
    Tree diversity across different tropical agricultural land use types2017Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 240, s. 92-100Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A recent trend in conservation biology is not only to focus on protected areas of natural vegetation but also on the management of agricultural landscapes, since these landscapes are considered to be-of vital importance for overall landscape biodiversity both through the opportunity for species to thrive there and as conduits for inter-patch dispersal. Since trees are considered to be key structures to enhance biodiversity in agricultural landscapes, we need to understand what factors regulate their occurrences. Farmers choices will decide the composition of land-uses and the associated densities and composition of trees. We compared tree density and tree species composition across eight different land use types replicated in ten agricultural landscapes in relatively humid climates of mid-altitudes (1500-2500 m asl) in Ethiopia. In each landscape five transects of 1 km divided into 50 plots of 20 x 20 m were surveyed for woody plants. Annual crop plots had a low tree density (of trees >10 cm DBH) (6 per ha), but since it generally was the most abundant land use type altogether, many tree species were still found there (4-29 per transect in the different landscapes). Most tree species had their highest relative occurrence in the perenial crops land-use type and among the different perenial crop types, plots with coffee were more species rich than plots with khat (Catha edulis) (a stimulant crop increasing in frequency); plots with Eucalyptus trees were intermediate. A few species were more associated with grazing areas and homegardens indicating that a combination of land-uses enhances the overall species diversity in these agricultural landscapes. However, if the trend of increasing areas of khat and Eucalyptus would lead to decreases in shade coffee there is a risk for severe erosion of tree density and species richness across these landscapes with cascading effects on associated biodiversity.

  • 5.
    Lemessa, Debissa
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Hylander, Kristoffer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Hambäck, Peter
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Composition of crops and land-use types in relation to crop raiding pattern at different distances from forests2013Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 167, s. 71-78Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Among the issues that farmers need to account for when planning their land-use and crop choice is yield loss from wild animals. The aim of this study was to examine both the distribution of land-use types and crops (in fields and homegardens) in relation to distance from forest edges and the possible impact of crop raiding mammals. Thirty transects of 1 km in length were laid out in a pair-wise design - 15 close to (<= 0.3 km) and 15 far from (1-3.5 km) forest edges. We measured the cover of the land-use types and field crops in each transect and assessed crop species composition in 4-6 homegardens along each transect. We also conducted a questionnaire survey for the occurrence of baboons and bush pigs in maize fields and in homegardens. Our results indicated that the distribution of land-use types and field crops was not significantly different between sites close to and far from forest edges. Similarly, the distributions of field and homegarden crop species composition were also similar between these locations. The occurrence pattern of baboons and bush pigs coming to the fields and homegardens was however strongly inclined toward transects close to forest edges according to the answers from the farmers. Although crops, such as maize, sorghum, tuber and root crops are frequently attacked by either baboons or pigs or both, farmers apparently did not stop growing these crops. The major reasons for this lack of response in growing practices between sites close to and far from forests could either be a perceived lack of alternative less susceptible crops or that farmers have adapted different protection mechanisms for the problem to be manageable. Both ecological and socio-economic studies are needed in order to understand the variation (and sometimes lack of variation) of ecosystem properties and corresponding management practices across landscapes.

  • 6. Lemessa, Debissa
    et al.
    Samnegård, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Hambäck, Peter A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Hylander, Kristoffer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Tree cover mediates the effect on rapeseed leaf damage of excluding predatory arthropods, but in an unexpected way2015Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 211, s. 57-64Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Birds and predatory arthropods are often implicated in pest control, but their relative impact and how this is mediated by variation in tree cover requires elucidation. We excluded birds and ground predatory arthropods from rapeseed plants in 2.5 x 1 m plots in 26 homegardens in Ethiopia, leaving the same sized control plots. From six groups of plants in bird exclosure and control plots, respectively, three groups were excluded from ground predatory arthropods. Data on leaf damage were surveyed four times at weekly intervals. The tree cover and land-use composition within 100 x 100 m surrounding each plots were recorded in the field and from a satellite image within 200 and 500 m buffer zones. The results show that the mean leaf damage was higher on rapeseed plants from which predatory arthropods were excluded than on control plants. However, excluding birds had no or only a weak impact on leaf damage. The mean leaf damage within predatory arthropod exclosures decreased with increasing tree, forest and perennial cover but increased with increasing grazing land cover and annual crop cover, while on control plants it was low across the tree cover variation. This pattern may indicate the presence of a higher density of herbivores on rapeseed plants and also more predatory arthropods (i.e., to control them) in tree-poor homegardens compared to tree-rich homegardens. Hence, tree-poor homegardens in this landscape have sufficient habitat heterogeneity to support natural enemies to deliver significant pest control on rapeseed. Our results show that there was variation in the dynamics of pests and predatory arthropods across the tree cover variation, suggesting changes in landscape composition could affect the pest control services and the outcomes for local farmers.

  • 7.
    Lindgren, Jessica
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Lindborg, Regina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Cousins, Sara A. O.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Local conditions in small habitats and surrounding landscape are important for pollination services, biological pest control and seed predation2018Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 251, s. 107-113Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Small semi-natural and natural habitats in agricultural landscapes are important for biodiversity. With modern and more intensive agricultural practices they have become smaller (less than 1600 m2) and more isolated study which also affects ecosystem functions. Most ecosystem function studies using field experiments focus on a single function. Here, we investigate three functions in the same landscape at the same time. We investigated how local (trees, shrubs and grass-cover in small remnant habitats) and landscape factors (amount of and distance from key habitats i.e. forest and semi-natural grasslands) affect pollination, biological pest control and seed predation. We applied a multifunctional approach using different organisms to analyze pollination success (Primula veris), predation on aphid pests (Rhopalosiphum padi) and seed predation (of Helianthus annuus). A set-up of 3 different experiments were placed in situ on 12 midfield islets. Pollination was more affected by local factors than landscape factors, although pollination success was improved by a smaller proportions of surrounding crop fields. Seed predation was higher on islets with more surrounding forest and also with more trees on the habitat, especially close to shrubs, compared to more open areas of habitat. Predation on aphids decreased on midfield islets with a larger amount of nearby forest but was positively affected by increasing local tree cover on the habitat.

    We show that managing semi-open habitats that are connected to other natural or semi-natural habitats can improve pollination success and biological pest and weed control, thus potentially increasing yield in surrounding crop fields.

  • 8.
    Samnegård, Ulrika
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Hambäck, Peter A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Eardley, Connal
    Nemomissa, Sileshi
    Hylander, Kristoffer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Turnover in bee species composition and functional trait distributions between seasons in a tropical agricultural landscape2015Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 211, s. 185-194Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A comprehensive understanding of how spatial variation across landscapes regulates local abundances and species richness also needs to consider possible temporal changes in such relationships. In many tropical areas, the contrast between dry and rainy season is pronounced and the types and distributions of the main floral resources differ (herbs vs trees). This shift in resources could result in different pollinator abundances, species richness and trait compositions between seasons, as well as in how these components are spatially distributed. We compared the bee species composition between dry and rainy season in an agricultural mosaic landscape in southwestern Ethiopia, and analyzed it in relation to forest cover. We sampled bees for 67 days in the dry season and 86 days in the rainy season with pan and vane traps in 28 homegardens covering a gradient from low to high tree cover in the surrounding area. We found a clear shift in species composition between seasons, with more small bee species and more below-ground nesting bees in the rainy season compared to the dry season. The distribution of height at which the bees were foraging shifted between seasons with a higher proportion of the bees foraging at tree level in the dry season. Bee abundance and richness were generally positively affected by higher forest cover surrounding the homegardens, but there were no clear interaction effects between seasons, in contrast to our hypothesis. The clear turnover in species composition between seasons and the positive effect of forest cover show that mechanisms acting both at spatial and temporal scales are important in regulating local bee communities.

  • 9.
    Sinare, Hanna
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Gordon, Line J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Ecosystem services from woody vegetation on agricultural lands in Sudano-Sahelian West Africa2015Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 200, s. 186-199Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Investment in woody vegetation to counter land degradation and improve livelihoods is increasing, primarily revitalized by efforts to enhance carbon sequestration and climate change adaptation. Sudano-Sahelian West Africa is in focus for several interventions to increase woody vegetation for improved livelihoods. However, the knowledge on how woody vegetation maintains landscape productivity and contributes to livelihoods is widely scattered across different scientific fields. Here we review different bodies of literature including a total of 30 species of woody vegetation. We use ecosystem services as a lens to integrate knowledge about how woody vegetation affect ecosystem processes and contribute to livelihoods. We find that the majority of the species generate multiple provisioning ecosystem services. Medicinal uses, contribution to fodder for livestock and importance for human nutrition are reported for almost all species. Regulating ecosystem services are studied for a more narrow set of species. There are mainly positive or no effects on soil nutrients, soil carbon and soil water content. The overall effect of woody vegetation on crop yields is mediated through multiple processes and shows both positive and negative effects. The majority of studies are focused on effects of individual elements of woody vegetation, with very limited landscape scale analyses. Differences between beneficiaries of ecosystem services are only discussed in a few studies, and only in relation provisioning services. Therefore, future studies need to address landscape scale effects and how the benefits of ecosystem services are distributed among beneficiaries, to provide knowledge that is even more relevant for interventions that aim to enhance climate mitigation and adaptation, ecosystem restoration, as well as poverty alleviation.

  • 10.
    Öster, Mathias
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Ask, Kristina
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Römermann, Christine
    Tackenberg, Oliver
    Eriksson, Ove
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Plant colonization of ex-arable fields from adjacent species-rich grasslands: the importance of dispersal vs. recruitment ability2009Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 130, nr 3-4, s. 93-99Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Species-rich semi-natural grasslands have declined drastically in Europe over the last century and occur in modern landscapes as small and isolated fragments. Recreation of these species-rich plant communities and increasing connectivity of remaining grasslands are important goals for nature conservation. Ex-arable fields located adjacent to species-rich grasslands have been suggested as targets for such recreation, but we still lack knowledge about the processes determining colonization from grasslands to ex-arable fields. We examined transects from species-rich semi-natural grasslands to ex-arable fields in a nature reserve located in southeast Sweden, and analysed relationships between observed colonization of ex-arable fields and two characteristics of species: dispersal ability and recruitment ability. Colonization of ex-arable fields was not related to dispersal ability, assessed as adhesive potential to animal coat, wind dispersal potential and seed mass (related to seed production), but was positively related to recruitment ability, assessed by sowing experiment. The same relationships appeared when using a performance index from sowing experiments conducted in the UK. We conclude that recruitment ability is a key factor for colonization of ex-arable fields. In our study, around 50% of semi-natural grassland species were able to colonize adjacent ex-arable field margins spontaneously within a time window of less than 50 years. Seed sowing is however needed to increase the speed of the colonization process, because increasing seed density promotes colonization of species with poor recruitment in ex-arable fields. Actions to increase area and connectivity of species-rich grasslands should consider incorporating ex-arable fields.

  • 11.
    Öster, Mathias
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Persson, Kill
    Eriksson, Ove
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Validation of plant diversity indicators in semi-natural grasslands2008Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 125, nr 1-4, s. 65-72Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The use of plant biodiversity indicators in a nationwide survey of semi-natural grasslands in Sweden was examined by comparing results from the survey with additional in-depth studies of plant diversity at the same 30 sites in southern Sweden. Additional grasslands, that were not subjected to the nationwide survey (i.e. rejected after an initial site selection), were also investigated in order to examine the quality of the initial site selection and to assess to what extent they harboured species rich plant communities. Results showed that grasslands that were not included in the nationwide survey were generally smaller in size and that they contained significantly lower plant diversity than sites that were included by the survey. However, some indicator species, including indicators for poor management, were abundant in both types of sites. Biodiversity indicators correctly indicated both plant species richness and plant species density when using data from the in-depth study. However, by comparing indicator species found by the nationwide survey and by the in-depth study, it was shown that the survey overlooked 42% of all indicator species occurrences, which removed the significant relationship between indicator richness and total plant species richness. Furthermore, a null model showed that the chosen indicator species did not perform significantly better than species chosen at random from the available species pool. The conclusion was that validation of indicators is crucial, because even though real correlations exist between taxa or between a subset of species and overall diversity, poor precision of surveys might make these indicators useless. This also suggests that the effort put into searching for the indicator species may have to be so high, that it may be more efficient to go directly into assessing the biological values they are supposed to indicate.

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