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  • 51.
    Mulokozi, Deogratias Pius
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography. University of Dar es Salaam, Tanzania; Tanzania Fisheries Research Institute, Tanzania.
    Mmanda, Francis Pius
    Onyango, Paul
    Lundh, Torbjörn
    Tamatamah, Rashid
    Berg, Håkan
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Rural aquaculture: Assessment of its contribution to household income and farmers' perception in selected districts, Tanzania2020In: Aquaculture Economics & Management, ISSN 1365-7305, E-ISSN 1551-8663, Vol. 24, no 4, p. 387-405Article in journal (Refereed)
    Abstract [en]

    Rural fish farming is being promoted as a good source of protein and income diversification to fight poverty and inequality. However, its actual contribution to these rural households and local community at large is little known. Through interviews with 89 farmers' and 6 key informants, we examined the contribution of rural fish farming to local farmers' household income and investigate farmers' perceptions, opportunities, and constraints towards fish farming in six districts of Tanzania. Results indicated that fish farming contributed on average 13% to household incomes and that it explained 5% of the variation of the household income while 84% of the variation was due to non-fish sources. The majority (79%) of the farmers wanted to continue with fish farming, 9% planned to quit, and 12% had not decided whether to continue or not. Conclusively, much higher aquaculture contribution towards rural development could be obtained if appropriate measures are taken.

  • 52.
    Nguyen, Thanh Tam
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography. Nong Lam University, Vietnam.
    Berg, Håkan
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Nguyen, Hang Thi Thuy
    Van Nguyen, Cong
    Effects of chlorpyrifos ethyl on acetylcholinesterase activity in climbing perch cultured in rice fields in the Mekong Delta, Vietnam2015In: Ecotoxicology and Environmental Safety, ISSN 0147-6513, E-ISSN 1090-2414, Vol. 117, p. 34-40Article in journal (Refereed)
    Abstract [en]

    Climbing perch is commonly harvested in rice fields and associated wetlands in the Mekong Delta. Despite its importance in providing food and income to local households, there is little information how this fish species is affected by the high use of pesticides in rice farming. Organophosphate insecticides, such as chlorpyrifos ethyl, which are highly toxic to aquatic organisms, are commonly used in the Mekong Delta. This study shows that the brain acetylcholinesterase (AChE) activity in climbing perch fingerlings cultured in rice fields, was significantly inhibited by a single application of chlorpyrifos ethyl, at doses commonly applied by rice farmers (032-0.64 kg/ha). The water concentration of chlorpyrifos ethyl decreased below the detection level within 3 days, but the inhibition of brain AChE activity remained for more than 12 days. In addition, the chlorpyrifos ethyl treatments had a significant impact on the survival and growth rates of climbing perch fingerlings, which were proportional to the exposure levels. The results indicate that the high use of pesticides among rice farmers in the Mekong Delta could have a negative impact on aquatic organisms and fish yields, with implications for the aquatic biodiversity, local people's livelihoods and the aquaculture industry in the Mekong Delta.

  • 53.
    Nilsson, Mats
    et al.
    Fjärranalys, SLU Umeå.
    Granholm, Ann-Helen
    Fjärranalys, SLU Umeå.
    Nordqvist, Karin
    SLU, Umeå.
    Skånes, Helle
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology (INK).
    Computer classification of General Habitat Categories by combining LiDAR and SPOT data2010Conference paper (Other academic)
    Abstract [en]

    General Habitat Categories (GHC) is a classification scheme developed in BioHab1, 2 and a central concept in EBONE3. A characteristic of GHC is plant height, which can be derived using Light Detection And Ranging (LiDAR) data. Computer classification of GHCs might be improved by combining spectral information in optical satellite data with LiDAR. The aim of this pilot study was to investi­gate to which degree airborne LiDAR improves SPOT data based classification of a selection of GHCs in a for­est area in southern Sweden. Lat. 58° 30’ N Long 13° 40’ E. Managed forest with Scots pine (Pinus Sylvestris), Norway spruce (Picea Abies) and birch (Betula spp). A SPOT 5 HRG XS scene. Airborne LiDAR data with an average point density of 26 returns/m2. Photo interpretation of GHCs, 585 sample plots, in aerial DMC images. Combining LiDAR and SPOT data shows promise, considering the restrictions to this study. In a similar study, using the same dataset for classifying CORINE land cover types, overall accuracy increased from 67.1% to 77.6% when add­ing LiDAR data4. This means that there is potential, though the methods need improvement and further tests should include a larger test area providing adequate amounts of sample plots per GHC.

  • 54.
    Nilsson, Mats
    et al.
    Fjärranalys, SLU Umeå.
    Holm, Sören
    Fjärranalys, SLU Umeå.
    Allard, Anna
    Institutionen för Skoglig Resurshushållning .
    Skånes, Helle
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology (INK).
    Integration of earth observation data and in situ data from the National Inventory of Landscapes in Sweden (NILS)2010Conference paper (Other academic)
    Abstract [en]

    Integration of in situ data and earth observation (EO) data for estimating the occurrence of different habitat or classes can be achieved using different approaches. In this study, the approach used is to post-stratify in situ data using existing land cover maps derived from satellite data. Photo-interpreted landscape elements and biotopes from the National Inventory of Landscapes in Sweden (NILS; http://nils.slu.se/) were used as in situ data. The mapped landscape elements and biotopes were classified into General Habitat Categories (GHCs). Five of the GHCs were selected to exemplify how the precision of their area estimates was affected by using post-stratification, as compared to area estimates of the GHCs based on the photo-interpreted data alone. The stratification was made using the Swedish version of Corine land cover (SMD) which includes more classes and has a higher spatial resolution (1-25 ha minimum mapping unit depending on the class) than the European version of Corine land cover (CLC). The results show that the standard error was reduced substantially for all tested GHCs using post-stratification in comparison to the errors obtained without post-stratification. This shows the potential to derive improved area statistics of habitat categories by integrating in situ data with existing land cover maps.

  • 55.
    Nurihun, Biruk Ayalew
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Hylander, Kristoffer
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Adugna, Girma
    Zewdie, Beyene
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Tack, Ayco J. M.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Impact of climate on a host-hyperparasite interaction on Arabica coffee in its native rangeManuscript (preprint) (Other academic)
    Abstract [en]
    1. Natural enemies of plant pathogens might play an important role in suppressing plant disease levels in natural and agricultural systems. Yet, plant pathogen-natural enemy interactions might be sensitive to changes in the climate. Understanding the relationship between climate, plant pathogens, and their natural enemies is thus important for developing climate-resilient, sustainable agriculture.
    2. To this aim, we recorded shade cover, daily minimum and maximum temperature, relative humidity, coffee leaf rust, and its hyperparasite at 58 sites in southwestern Ethiopia during the dry and wet season for two years
    3. Coffee leaf rust severity was positively related to maximum temperature and hyperparasite severity was higher when the minimum temperature was low (i.e. in places with cold night temperatures) during three of the four surveying periods. While canopy cover did not have a direct effect on rust severity, it reduced rust severity indirectly by lowering the maximum temperature. Canopy cover had a direct positive effect on hyperparasite severity.
    4. Synthesis and applications. Our findings highlight that coffee leaf rust and its hyperparasite are both affected by shade cover and temperature, but in different ways. On the one hand, these niche differences between coffee leaf rust and its hyperparasite provide opportunities to develop strategies to manage the environment (such as shade cover and microclimate) in such a way that the rust is disfavored and the hyperparasite is favored. On the other hand, these niche differences lead to the worrying prediction that levels of coffee leaf rust will increase, and its hyperparasite will decrease, with climate change.
  • 56.
    Nurihun, Biruk Ayalew
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Hylander, Kristoffer
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Adugna, Girma
    Zewdie, Beyene
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Zignol, Francesco
    Tack, Ayco J. M.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Impact of climate and management on coffee berry disease and yield in Arabica coffee’s native rangeManuscript (preprint) (Other academic)
    Abstract [en]

    Climate change might increase plant diseases, reduce crop yields and threaten the livelihoods of millions of smallholder farmers globally. It is thus important to understand the relationships between climate, disease levels and yield to improve management strategies for sustainable agroforestry in a changing climate. One of the major threats to coffee production in Africa is coffee berry disease, caused by the fungal pathogen Colletotrichum kahawae. To investigate the effects of climatic and management variables on coffee berry disease and yield, we recorded daily minimum and maximum temperature and relative humidity, as well as incidence of coffee berry disease and yield in 58 sites along a broad environmental and management gradient in southwestern Ethiopia in both 2018 and 2019. Coffee berry disease was affected by several climatic and management variables, with relatively high consistency between years. For example, coffee berry disease incidence was higher in sites with high minimum temperatures during the fruit expansion stage from March to April, and was lower in sites with high minimum temperatures during the endosperm filling stage from May to June. Coffee berry disease incidence was negatively affected by the proportion of resistant cultivars, whereas management intensity had no effect on disease incidence. Coffee yield decreased with increasing minimum and maximum temperatures during the flowering period in 2018 and the fruit developmental period in 2019, respectively. Coffee yield was negatively affected by canopy cover, and positively affected by management intensity, in both years. Our findings highlight that coffee berry disease and yield were affected by different climatic and management variables. Yet, managing for low disease-high yield is practically difficult, as the effect of several climatic variables was season-dependent, and at the same time climatic variables were highly correlated between seasons. One way to break the correlation of climatic variables between seasons might be to take advantage of differences among shade trees in the presence or timing of leaf drop. To reduce levels of coffee berry disease, an effective strategy is to use resistant cultivars, but this might threaten the wild coffee genetic reservoir.

  • 57.
    Nurihun, Biruk Ayalew
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Hylander, Kristoffer
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Börjeson, Lowe
    Stockholm University, Faculty of Social Sciences, Department of Human Geography.
    Adugna, Girma
    Beche, Dinkissa
    Tack, Ayco J. M.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, The Bolin Centre for Climate Research (together with KTH & SMHI).
    Using local knowledge to reconstruct climate-mediated changes in disease dynamics and yield – a case study on Arabica coffee in its area of originManuscript (preprint) (Other academic)
    Abstract [en]
    • While some countries have monitored major crop diseases for several decades or centuries, other countries have very limited historical time series. In such areas, we lack data on long-term patterns and drivers of disease dynamics, which is important for developing climate-resilient disease management strategies. 
    • We adopted a novel approach, combining local knowledge, climate data, and spatial field surveys to understand long-term climate-mediated changes in disease dynamics in coffee agroforestry systems. For this, we worked with 58 smallholder farmers in southwestern Ethiopia, the area of origin of Arabica coffee.
    • The majority of farmers perceived an increase in coffee leaf rust and a decrease in coffee berry disease, whereas perceptions of changes in coffee wilt disease and Armillaria root rot were highly variable among farmers. Climate data supported farmers’ understanding on the climatic drivers (increased temperature, less rainy days) of these changes. Temporal disease-climate relationships were matched by spatial disease-climate relationships, as expected with space-for-time substitution.
    • Understanding long-term disease dynamics and yield is crucial to adapt disease management to climate change. Our study demonstrates how to combine local knowledge, climate data and spatial field surveys to reconstruct disease time series and postulate hypotheses for disease-climate relationships in areas where few long-term time-series exist.
  • 58. Petersson, Erik V.
    et al.
    Arif, Usman
    Schulzova, Vera
    Krtkova, Veronika
    Hajslova, Jana
    Meijer, Johan
    Andersson, Hans Christer
    Jonsson, Lisbeth
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Sitbon, Folke
    Glycoalkaloid and Calystegine Levels in Table Potato Cultivars Subjected to Wounding, Light, and Heat Treatments2013In: Journal of Agricultural and Food Chemistry, ISSN 0021-8561, E-ISSN 1520-5118, Vol. 61, no 24, p. 5893-5902Article in journal (Refereed)
    Abstract [en]

    Potato tubers naturally contain a number of defense substances, some of which are of major concern for food safety. Among these substances are the glycoalkaloids and calystegines. We have here analyzed levels of glycoalkaloids (alpha-chaconine and a-solanine) and calystegines (A(3), B-2, and B-4) in potato tubers subjected to mechanical wounding, light exposure, or elevated temperature: stress treatments that are known or anticipated to induce glycoalkaloid levels. Basal glycoalkaloid levels in tubers varied between potato cultivars. Wounding and light exposure, but not heat, increased tuber glycoalkaloid levels, and the relative response differed among the cultivars. Also, calystegine levels varied between cultivars, with calystegine B-4 showing the most marked variation. However, the total calystegine level was not affected by wounding or light exposure. The results demonstrate a strong variation among potato cultivars with regard to postharvest glycoalkaloid increases, and they suggest that the biosynthesis of glycoalkaloids and calystegines occurs independently of each other.

  • 59.
    Piemontese, Luigi
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Sustainable Land and Water Management for a Greener Future: Large-scale insights in support of Agroecological Intensification2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The challenge of producing more food in times of climate change, degraded land and scares water resources is calling for a radical transformation of agriculture. Sustainable agricultural intensification is the process of increasing the productivity of farms while preserving functional ecosystems. A range of sustainable land and water management (SLWM) practices and approaches to sustainable intensification have been successfully implemented at the local scale during the last decades, but adoption rate remains low due to a variety of barriers and lack of effective approaches from authorities at larger scales (national to global). Despite the wealth of local successes, promoting and realizing the widespread uptake of SLWM requires large scale understanding of the potential and challenges of adoption of SLWM, which is currently lacking. This thesis bridges outcomes of successful implementation of SLWM from local cases to large scale social-ecological patterns, showing where and what is the potential of SLWM to contribute to sustainable agricultural intensification and the barriers to achieve it. The methodological approach and the results presented in this thesis aim at providing insights to improve current assessments of sustainable intensification of agriculture and practical guidance to planning, policy making and funding interventions to promote the widespread adoption of SLWM.

    Download full text (pdf)
    Sustainable Land and Water Management for a Greener Future: Large-scale insights in support of Agroecological Intensification
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  • 60.
    Resare Sahlin, Kajsa
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Delicious Sustainability?: Synergies and goal conflicts between eating quality and environmental sustainability in Swedish beef production2018Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Improved production and reduced consumption of beef is often highlighted as key aspects for tackling sustainability issues of the food system because the environmental impact of beef is ~100 times higher than plant-based foods. Both scientist and civil society organisations argue that eating “less but better” beef is important for sustainability. Better quality can encompass better eating quality as well as improved sustainability, but despite the two being very important for overall quality, very little research on interactions between them exists. No tools, applicable in Sweden, allowing for joint assessment have been developed. This study investigates the synergies and trade-offs between eating quality and environmental sustainability by using Swedish beef production as a case study. It reviews peer reviewed literature on factors that contribute to eating quality (flavour, tenderness and juiciness), and four factors that contribute to environmental sustainability (climate, biodiversity, feed/food competition and animal welfare). Based on the findings, an indicator-based sustainability assessment framework and a meat quality grading scheme differentiating Premium and Standard eating quality is developed, aimed to be practical tools for Swedish beef assessments. The study provides a systems-based understanding of synergies and trade-offs that may occur when “less but better” is presented as a strategy for tackling the environmental impact of beef. Results show that there are synergies between eating quality and biodiversity, animal welfare and with the right choices of feed, feed/food competition but with consequent trade-offs with climate impact. The discussion addresses the potential of enhanced eating quality to increase the profitability of Swedish beef production without consequent substantial negative impact on sustainability. The suggested methods have the potential to facilitate a shift from quantity- to quality-based consumption, but further empirical studies are required.

    Download full text (pdf)
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  • 61.
    Runefelt, Leif
    Stockholm University, Faculty of Humanities, Department of History.
    Inledning2008In: Svensk mosskultur: Odling, torvanvändning och landskapets förändring 1750-2000, 2008, p. 11-25Chapter in book (Other academic)
  • 62.
    Runefelt, Leif
    Stockholm University, Faculty of Humanities, Department of History.
    Mosskultur i Europa 1870-19452008In: Svensk mosskultur: Odling, torvanvändning och landskapets förändring 1750-2000, k. Skogs- och lantbruksakademien , 2008, p. 273-304Chapter in book (Other academic)
  • 63.
    Runefelt, Leif
    Stockholm University, Faculty of Humanities, Department of History.
    Svensk mosskultur: odling, torvanvändning och landskapets förändring 1750-20002010Collection (editor) (Other academic)
    Abstract [en]

    This book contains all you ever wanted to know about Swedish moor cultivation. If you're interested in the subject, this is the only possible startingpoint.

  • 64.
    Runefelt, Leif
    Stockholm University, Faculty of Humanities, Department of History.
    Svensk mosskultur som överhetsprojekt före 18862008In: Svensk mosskultur: Odling, torvanvändning och landskapets förändring 1750-2000, 2008, p. 27-52Chapter in book (Other academic)
  • 65.
    Runefelt, Leif
    Stockholm University, Faculty of Humanities, Department of History.
    Svenska Mosskulturföreningen 1886-19392008In: Svensk mosskultur: Odling, torvanvändning och landskapets förändring 1750-2000, k. Skogs- och lantbruksakademien , 2008, p. 53-95Chapter in book (Other academic)
  • 66.
    Runefelt, Leif
    Stockholm University, Faculty of Humanities, Department of History.
    Torvbubblan 1900-19252008In: Svensk mosskultur: Odling, torvanvändning och landskapets förändring 1750-2000, k. Skogs- och lantbruksakademien , 2008, p. 329-357Chapter in book (Other academic)
  • 67. Saeed, Muhammad
    et al.
    Quraishi, Umar Masood
    Mustafa, Ghazala
    Farooqi, Abida
    Greger, Maria
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Malik, Riffat Naseem
    Metabolomics profiling reveals the detoxification and tolerance behavior of two bread wheat (Triticum aestivum L.) varieties under arsenate stress2024In: Food Chemistry, ISSN 0308-8146, E-ISSN 1873-7072, Vol. 443, article id 138612Article in journal (Refereed)
    Abstract [en]

    The present study conducted metabolomics profiling (targeted and untargeted) in the roots of two wheat varieties (BARANI-70 and NARC-09) under arsenate stress in a hydroponic experiment. The findings indicated a better growth response of BARANI-70 compared to the NARC-09. From amino acid profiling, a total of 26 amino acids (AAs) were quantified in roots. BARANI-70 showed higher induction of stress-responsive AAs compared to the NARC-09. From untargeted metabolomics, a total of 136 metabolites were identified: AAs, fatty acids, purines, carnitines, LysoPCs, and others. The KEGG pathway identified pathways such as linoleic acid metabolism, TCA cycle, glutathione metabolism, and aminoacyl-tRNA biosynthesis that were regulated to improve the defense of tolerant variety. BARANI-70 emerged as a tolerant variety based on the psychological response, As accumulation, and behavior of stress-responsive metabolites. This study should facilitate the breeding of low-As accumulating wheat varieties for future application to ensure sustainable production and food safety.

  • 68.
    Sanderson Bellamy, Angelina
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Export Banana production systems in Costa Rica: identification of alternative systems for more sustainable productionIn: Ambio, ISSN 0044-7447, E-ISSN 1654-7209Article in journal (Refereed)
    Abstract [en]

    Green revolution technologies transformed agricultural production. Large-scale, monocropped systems dependent on synthetic fertilizers and pesticides have become the norm for export crop production. This production system, while increasing yields, has deleterious impacts on human health and the environment. This research investigates the level of variation in production practices for export banana production inCosta Rica, in order to identify pioneering producers, who have managed to transform production practices to reduce agrochemical use. Thirty-nine banana producers were interviewed. Correspondence analysis showed that there is not structured variation in export banana producers’ practices, but two other banana production systems identified produce bananas for processing and for the national market: an organic production system and a coffee-banana intercropped system. Although they target different markets, systems level research may reveal ways that these practices can be scaled up to achieve a productive and profitable system producing high-quality export bananas with fewer or no pesticides.

  • 69. Shimales, Tamiru
    et al.
    Mendesil, Esayas
    Zewdie, Beyene
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Department of Horticulture & Plant Sciences, Ethiopia.
    Ayalew, Biruk
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, The Bolin Centre for Climate Research (together with KTH & SMHI).
    Hylander, Kristoffer
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, The Bolin Centre for Climate Research (together with KTH & SMHI).
    Tack, Ayco J. M.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, The Bolin Centre for Climate Research (together with KTH & SMHI).
    Management intensity affects insect pests and natural pest control on Arabica coffee in its native range2023In: Journal of Applied Ecology, ISSN 0021-8901, E-ISSN 1365-2664, Vol. 60, no 5, p. 911-922Article in journal (Refereed)
    Abstract [en]

    1. Agroforestry systems provide opportunities to reduce the trade -off between agricultural production and biodiversity, for example by enhancing a diverse community of species potentially acting as natural pest control agents. While management of agroforestry systems is intensifying across the globe, we lack insights into the impact of management intensity on pest levels and natural pest control, especially along broad management gradients and as compared with nat- ural forests.

    2. We assessed the impact of management intensity on major insect pests (the coffee blotch miner, the serpentine leaf miner, the coffee leaf skeletonizer and damage by other free-feeding herbivores) and natural pest control by parasitoid wasps across sixty sites in the centre of origin of Arabica coffee in southwestern Ethiopia. Within this region, coffee is growing along a broad management gradi- ent ranging from little or no management in the natural forest to intensively man- aged commercial plantations.

    3. In the wet season, pest levels were largely similar in the natural forest, semi-forest and semi-plantation systems, whereas pests reached outbreak densities in the most intensively managed plantation system. In contrast, management intensity did not significantly affect pest levels in the dry season. The insect pests differed in their seasonal dynamics, consistently declined with elevation and were largely unaffected by shade levels. Parasitism rate of the coffee blotch miner was lower, and the parasitoid community was distinct, in the most intensively managed plan- tation system.

    4. Synthesis and applications : Our findings support the hypothesis that the weaker top -down control by parasitoids in the intensively managed plantation sites leads to higher pest levels, and that - at least for some pest species - there is a threshold in the effect of management intensity on pest levels and natural pest control. It is important to consider such non-linear relationships to maintain or enhance the sustainability of agroforestry systems during management intensification. Overall, our findings highlight that ecological knowledge of natural pest control can be used to intensify production to improve the livelihood of smallholder farmers without jeopardizing natural pest control but only up to a certain point where it starts to deteriorate.

  • 70.
    Skånes, Helle
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology (INK).
    Andersson, Anna
    Lantmäteriet i Luleå.
    Flygbildstolkningsmanual för Uppföljningsprojektet Natura 2000 version 4.0: UF 192010Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Uppföljningsmanualen är indelad i fem kapitel.

    Kapitel 1.  Ger en kortfattad bakgrund som är gemensam för hela projektet och specifik för flygbildstolkningen.

    Kapitel 2.  Redovisar hur länsstyrelsen ska gå till väga för att på bästa sätt förbereda, planera och beställa uppföljning genom flygbildstolkning och vänder sig främst till länsstyrelsepersonalen. Flygbildstolkarna har god nytta av att känna till dessa rutiner för att på bästa sätt kunna utföra den beställda tolkningen. Här listas aktuella uppföljningsvariabler för denna manual samt ges en genomgång kring vilka naturtyper som finns föreslagna för uppföljning via flygbildstolkning i de olika uppföljningsmanualerna.

    Kapitel 3.  Vänder sig främst till flygbildstolkarna och redovisar rekommenderad arbetsgång för flygbildstolkning. Länsstyrelsen har god nytta av att känna till detta arbetssätt inför beställning och hantering av flygbildstolkade uppföljningsdata.

    Kapitel 4.  Går in på djupet kring de olika målindikatorer som kan beställas via flygbildstolkning och vänder sig främst till flygbildstolkarna. Länsstyrelsen har god nytta av att känna till detta arbetssätt inför såväl beställning som analys av flygbildstolkade uppföljningsdata.

    Kapitel 5.  Kort beskrivning av förfaranden kring leverans, kontroll och godkännande av flygbildstolkade data. Detta kapitel vänder sig till alla inblandade.

  • 71.
    Skånes, Helle
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology (INK).
    Glimskär, Anders
    Institutionen för ekologi, SLU Uppsala.
    Allard, Anna
    Institutionen för Skoglig Resurshushållning .
    Visual interpretation of key properties in vegetation structur from Lidar data: potential importance for physical, ecological and socio-economic monitoring2010Conference paper (Other academic)
    Abstract [en]

    This paper discusses early findings from one of several projects within a recently launched research program devoted to environmental mapping and monitoring with airborne laser and digital images (EMMA) financed by the Swedish EPA. Policy makers and land managers along with the global community increasingly demand hard figures regarding the state and trends of biodiversity and habitat qualities of importance to nature conservation and international environmental quality goals. Although remote sensing and GIS based methods have greatly improved, there is still a lack of spatially detailed and consistent habitat data to meet these requirements. Key vegetation qualities are often hidden from visual and automatic classification in high resolution remote sensing imagery since they are typically covered by trees. Laser beams can partly penetrate through the canopy and the data derived from the reflected pulses will add crucial detail and consistency in vegetation mapping. The aim of the project is to visually explore LiDAR data focusing on habitats within agricultural and alpine environments for enhanced vegetation classification and registration of habitat qualities and structures. Initially a number of key variables (vertical and horizontal structure, influence of land use, and site conditions) have been explored through visual interpretation of two time sets of high resolution 3D laser point data (density>5 points/m²) and derivates processed to enhance objects of interest. The initial results from a wooded pasture indicate that key properties, such as ditches, field and shrub layer characteristics and distribution, fallen trees and various man made remnants are in fact detectable. The use of laser-generated high-quality bare earth models is crucial to distinguish the field layer and low shrubs from boulders and uneven ground surface. These bare earth models will as they become widely available enhance all types of habitat modeling and landscape analysis.

  • 72.
    Skånes, Helle
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology (INK).
    Glimskär, Anders
    Institutionen för ekologi, SLU Uppsala.
    Allard, Anna
    Institutionen för Skoglig Resurshushållning .
    Visuell tolkning av vegetationens strukturer och kvaliteter i laserskannade data2010Conference paper (Other academic)
    Abstract [sv]

    Presentation av initiala resultat från projektets första år där nyckelegenskaper i vegetationens vertikala och horisontella struktur har formulerats och utforskats i laserskannade punktdata. Syftet är att utforska möjligheterna till visuell tolkning av nyckelgenskaper i vegetation enligt EU:s habitatdirektiv i laserdata och att undersöka i vilken utsträckning olika vegetationstyper kan skiljas genom enkla bearbetningar av laserpunktmolnet. Målet på sikt är att undersöka hur kombinationen av automatiserad och visuell tolkning av laserdata kan förbättra naturvårdsrelaterade bedömningar och automatiska vegetationsklassificeringar. Fokus ligger på habitat inom alpina miljöer, odlingslandskap och kustzonen.

  • 73. Soares, Pedro R.
    et al.
    Harrison, Matthew T.
    Kalantari, Zahra
    Zhao, Wenwu
    Ferreira, Carla S. S.
    Stockholm University, Faculty of Science, Department of Physical Geography. Stockholm University, Faculty of Science, The Bolin Centre for Climate Research (together with KTH & SMHI). Polytechnic Institute of Coimbra, Portugal.
    Drought effects on soil organic carbon under different agricultural systems2023In: Environmental Research Communications (ERC), E-ISSN 2515-7620, Vol. 5, no 11, article id 112001Article, review/survey (Refereed)
    Abstract [en]

    Drought is a natural hazard occurring with increasing frequency due to climate change. Drought events reduce soil water content and also soil organic carbon (SOC) content, with negative impacts on crop development and food security. This study investigates the impact of drought on SOC dynamics in agricultural systems and the influence of water availability and farm management practices in these impacts. The manuscript is a systematic review, based on Scopus database for scoping the literature on the topic. A total of 283 records were retrieved, but only 16 papers were relevant for the review. The main findings are: (1) water plays a key role in regulating SOC mineralization due to its impact on dynamics of soil microbial communities, necessitating further research on water management to mitigate carbon losses during drought; (2) different agricultural systems can have differing impacts on SOC under drought conditions depending on crop type (e.g. pastures are more resilient than arable systems) and farm management practices; and (3) SOC loss generally occurs after a drought event, regardless of farm management regime, but the contribution of drought to this loss requires further research. Best management practices, such as cover cropping and soil amendment, can minimize SOC losses, but further research is required to optimize these practices in counteracting the effect of drought. A better understanding of the effects of drought on SOC dynamics, and of short-term and long-term ways to mitigate these effects, is important to ensure soil health and crop productivity.

  • 74.
    Waldén, Emelie
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Lindborg, Regina
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Facing the future for grassland restoration – What about the farmers?2018In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 227, p. 305-312Article in journal (Refereed)
    Abstract [en]

    In line with the 2010 Aichi Convention for Biological Diversity, the European Union has a goal to restore 15% of degraded ecosystems and their services by the year 2020 (target 2, Europe 2020). This includes restoration of semi-natural grasslands (SNGs). Management of both intact and restored SNGs is dependent on people's willingness to manage them. Due to low profitability, management abandonment still occurs all over Europe, which highlights the need to raise farmers' and landowners' perspectives. In this study, we combined survey data and in-depth interviews with farmers/landowners managing previously restored SNGs, to understand how they perceive the restoration process, the outcome and future management. Survey and interview data were analysed in relation to biodiversity and Agri-environmental payments data from the restored sites. Almost all respondents considered the restoration successful and the re-inventoried restored SNGs also showed an increase in plant diversity. Nevertheless, 10% of the restored SNGs were abandoned again post-restoration and 40% of the respondents were unsure if they would continue the management in the future. Abandoned management may cause a negative trend in terms of decreased biological, cultural and aesthetic values, in the local community, as well as for the society in general. Most respondents explained a strong dependency on Agri-environmental payments, both as a restoration incentive and for post-restoration management. Also non-financial support from authorities in form of feedback and advice was requested, as well as support from the local community and society as a whole. Future management in a longer time perspective was strongly coupled to the farm economy, i.e. received Agri-environmental payments at farm-level and profit from selling agricultural products, and whether the farmers had successors. We conclude that both social and ecological factors, here farm economy, authority support and proper management, must be in place for long-term success of grassland restoration.

  • 75.
    Widgren, Mats
    Stockholm University, Faculty of Social Sciences, Department of Human Geography.
    Towards a historical geography of intensive farming in eastern Africa2004In: Islands of intensive agriculture in Eastern Africa: Past and present / [ed] Mats Widgren & John Sutton, Oxford: James Currey Publishers, 2004Chapter in book (Other (popular science, discussion, etc.))
  • 76.
    Widgren, Mats
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Human Geography.
    Sutton, John E.G.
    Islands of intensive agriculture in Eastern Africa: past & present2004Book (Refereed)
    Abstract [en]

    Islands of intensive agriculture are areas of local cultivation surrounded by low-density livestock herders or extensive cultivators. Along the line of the East Africa Rift Valley, and in the highlands on either side, communities of considerable historical depth have developed highly specialized agricultural regimes, employing such labor-intensive devices as furrow irrigation, hillside terracing, and stall-feeding of cattle.

    This collection continues the advance in the understanding of African agricultural practices through the combination of geographical, ethnographic, and archaeological research, concentrating on actual fields, farming strategies, and cultivation techniques.

  • 77.
    Wästfelt, Anders
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Human Geography.
    Jansson, Johanna
    Arnberg, Wolter
    Moström, Jerker
    Nielsen, Michael
    Fjärranalys i kulturmiljövårdens tjänst2007Report (Other academic)
  • 78.
    Åberg, Amanda
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Rice yields under water-saving irrigation management: A meta-analysis2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Water scarcity combined with an increasing world population is creating pressure to develop new methods for producing food using less water. Rice is a staple crop with a very high water demand. This study examined the success in maintaining yields under water-saving irrigation management, including alternate wetting and drying (AWD). A meta-analysis was conducted examining yields under various types of water-saving irrigation compared to control plots kept under continuous flooding. The results indicated that yields can indeed be maintained under AWD as long as the field water level during the dry cycles is not allowed to drop below -15 cm, or the soil water potential is not allowed to drop below -10 kPa. Yields can likewise be maintained using irrigation intervals of 2 days, but the variability increases. Midseason drainage was not found to affect yield, though non-flooded conditions when maintained throughout most of the crop season appeared to be detrimental to yields. Increasingly negative effects on yields were found when increasing the severity of AWD or the length of the drainage periods. Potential benefits and drawbacks of water-saving irrigation management with regards to greenhouse gas emissions, soil quality and nutrient losses were discussed to highlight the complexity of the challenges of saving water in rice production. 

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