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Local stakeholder's perspectives on development of economic activities: The Gallivare case
Get PDFSweden's commitment to environmental conservation, social equity, and cultural preservation is challenged by intensifying resource extraction and land use conflicts. To ensure its continued equitable development, understanding and incorporating local perspectives into the decision-making process is necessary. Hence, this study seeks to understand current stakeholder views on the development of extractive industries i.e., mining and forestry; and traditional livelihood focusing on reindeer husbandry as defined by the human development theory and subjective capabilities. We used Gallivare, Sweden as our case study where all these economic activities are present and land use conflicts are intensifying. Through expert interviews and local stakeholder surveys using Qmethodology, we identified three perspectives: (1) Uncertain Development, (2) Prioritizing Nature and Reindeer, and (3) Industry Growth Equals Community Growth. We also found points of consensus and conflicts among these differing perspectives crucial for improving ongoing discussions and negotiations on land use conflicts. What remains clear is that development remains contested. Some groups express limited capabilities and freedom in pursuing the life they value hence development for some stakeholders is still far from reality as against reported indexes. Finally, we suggest that examining local stakeholder views on development can enhance the current monitoring of human development, especially in the Arctic region
Understanding predators through their prey
Get PDFSeabirds are the most threatened of all birds, with half of all populations being on decline due to anthropogenically driven changes to their environment. Many of the issues affecting seabirds are directly or indirectly tied to their foraging, but tracking seabirds’ food resources has been challenging due to their extensive ranges. With novel technologies, fine-scale information on prey distributions is increasingly accessible, enabling new insights into predator-prey interactions. In this thesis, I contribute with knowledge on how diving seabirds utilize and respond to dynamic prey landscapes, with a particular focus on niche divergence among closely related predators. I explored the ecological consequences of predator adaptations in relation to foraging behaviour, environmental variability, and the consequences of adaptations to seabirds’ conservation on a global scale. I first investigated the utility of hydroacoustic prey data monitored using an unmanned surface vehicle from April-July in 2019-2023 and predicted the spatiotemporal distribution of the small pelagic fish community. Then, I used biologging (GPS and dive loggers) of two diving seabirds, common guillemot (Uria aalge) and razorbills (Alca torda), to investigate their responses to diel distribution patterns of prey and found that their niche partitioning could be traced to divergent responses to prey distribution patterns and sensitivity to light levels. I further showed how common guillemots were dependent on predictable and stable foraging sites, but with clear responses in distance moved based on prey abundance and depth of site indicating active search. I finally zoomed out to the world’s seabirds and demonstrated how species-specific potential foraging range could be predicted by morphometrics and flying mode. This relationship was used to conclude that only 1% of the global seabirds’ foraging habitats during their breeding season are fully protected. By developing new methods and linking fine-scale behavioural responses to prey with broad-scale, trait-based conservation frameworks, this thesis provides a multiscale perspective on how foraging ecology in predators relates to marine ecosystems and prey fields. Such insights can inform biologically grounded conservation strategies for wide-ranging marine predators in a rapidly changing ocean
Long-Term Application of No-Tillage-Induced Greater Risk of Poor Topsoil Aeration Along a European Pedoclimatic Gradient
Get PDFThis paper assesses the effect of long-term contrasting tillage practices on topsoil structural characteristics critical for nitrous oxide (N2O) emissions and carbon sequestration across a pedoclimatic gradient. The hypotheses tested are that: (i) aeration is greater in the topsoil of ploughed (to 0.20-0.30 m depth) than in no-till soils and (ii) the effect of tillage practice on soil functionality depends on the context, and thus varies between sites with different pedoclimatic conditions. We evaluated the topsoil characteristics of seven long-term tillage experiments, spread along a 2600-km transect in Europe. A total of 576 soil cores (100-cm3) were sampled from 0 to 0.10 and 0.10 to 0.20 m depths in mouldboard-ploughed and no-tillage treatments after harvest. The soil water content at -30, -60, and -100 hPa matric potential was measured as well as air permeability (ka) and relative gas diffusivity (Ds/Do) at -100 hPa, from which soil bulk and gas transport characteristics were derived. Despite large variations in the characteristics among sites, tillage did significantly affect the characteristics across sites. The degree of compactness was less and total pore volume was greater in the ploughed than in the no-till treatments. Still, thresholds indicating suitable conditions for root growth were largely met under both practices. The ploughed soils showed vertical stratification, with a better aeration of the 0-0.10 m soil layer compared to the 0.10-0.20 m layer. No differences were observed between the ploughed 0.10-0.20 m and no-till layers, which were attributed to soil settlement after ploughing. While the Ds/Do at 0.10-0.20 m depth was favourable for promoting N2O emissions, the water-filled pore space was below suggested thresholds. Impacts of tillage on soil structural and functional characteristics were both significant and generalisable but also deviated locally. For example, Ds/Do and ka generally increased with the air-filled pore volume (epsilon a), yet sites with greater epsilon a did not necessarily have higher Ds/Do and ka. Existing models explaining Ds/Do and ka with epsilon a were fitted to the measured data and performed best when both depths and tillage practices were assessed altogether. Despite the limited differences at -100 hPa, anoxic conditions may in reality prevail for a longer period under no-till than ploughing
Divergent alpha and beta diversity trends of soil nematode fauna along gradients of environmental change in the Carpathian Ecoregion
Get PDFThere is a significant lack of research on how climate change influences long-term temporal trends in the biodiversity of soil organisms. Nematodes may be specifically adequate to test soil biodiversity changes, because they account for similar to 80% of all Metazoans and play key roles in the functioning of terrestrial ecosystems. Here, we report on the first synthesis study focused on temporal trends of nematode fauna over a period of 14 years (1986-1999) across the Carpathian Ecoregion. We provide new evidence that wetter conditions associated to global change contributes to driving nematode diversity at genus/family level. We observed opposite trends in soil nematode alpha diversity (increase) and beta diversity (decrease) consistent across ecosystem types and soil horizons, providing strong evidence for the influence of climate change on soil biodiversity at large spatial scales. An increase in the community functional uniformity along with a decline in beta diversity indicated more homogenous soil conditions over time. The Soil Stability Index (metric devised to assess soil homeostasis based on the functional composition of nematode communities) increased over time, indicating a decline of soil disturbances and more complex soil food webs. Our results highlight the importance of nematodes as powerful indicators of soil biodiversity trends affected by multiple facets of environmental change in long-term soil monitoring
Livelihood dynamics and challenges to wellbeing in the drylands of rural East Africa - the Drylands Transform study population in the Karamoja border region
Get PDFBackgroundThe Karamoja region in the East African drylands is a rural, impoverished setting where pastoralism is increasingly replaced by other livelihood strategies. Understanding the socioeconomic contexts as well as their local variations is key for sustainable development of communities.ObjectiveThe aim of the present paper is to describe the baseline survey of the Drylands Transform project, its setting, methods and key findings.MethodsIn June 2022, a survey was conducted with 944 randomly selected households at four study sites in the Karamoja border region of Kenya and Uganda. Data were analyzed using descriptive statistics.ResultsMain livelihood forms were pastoralism and agropastoralism, while many households also relied on other sources of income. At some study sites, livestock keeping was abandoned by many residents due to cattle raiding and droughts. Only 4% of households were rated as food secure. The proportion of malnutrition among children aged 6-59 months varied across sites between 3% and 17% and was considerably higher among women.ConclusionsClimate change, water shortage, social conflicts and marginalization pose barriers to food security and wellbeing for rural populations in the East African drylands. There are, however, opportunities for development through income diversification, the improvement of land health, the promotion of kitchen gardens and other measures of sustainable agriculture
Single- vs mixed-species plantations: A systematic review on the effects on biodiversity
Get PDFDespite increasing evidence suggesting mixed-species plantations promote biodiversity, a comprehensive quantitative analysis of this knowledge is lacking. We systematically reviewed 71 studies to evaluate the effects of mixed versus pure tree plantations on biodiversity. Using descriptive statistics and meta-analyses, we explored: a) the effects of mixed plantations on forest-related biodiversity; b) variations in these effects with climate, stand age, and with the richness, relative abundance, and functional diversity of the planted species; and c) differences in responses across taxonomic and functional groups. Our meta-analyses revealed a significant positive effect of mixed-species plantations on taxonomic diversity. However, most observations (64%) reported no significant effects. Positive effects are more frequent in mixtures with more than two species (49%), compared to twospecies mixtures (29%), and were strongest in tropical climates (78%), followed by temperate (26%) and continental climates (14%). Among taxonomic and functional groups, positive mixing effects are most frequent for birds (75%), followed by litter microbiota (47%), understory plants (40%), and above-ground arthropods (29%), while soil-dwelling micro-organisms (22%) and soil mesofauna (4%) appear less sensitive. Mixing conifers and broadleaves does not enhance biodiversity benefits, suggesting higher functional diversity may be better achieved by targeting specific species and traits. The limited effects of mixing observed in some cases may reflect the young age of plantations studied (11 +/- 9.4 years on average), which may limit the time for biodiversity to respond. The variability in biodiversity outcomes highlights the need for tailored mixing strategies and further research across broader plantation ages, settings, and underrepresented taxonomic groups to optimize biodiversity benefits in mixed-species plantations
Review of the importance of aquatic prey for riparian arthropod predators
Get PDFAquatic-derived resources can be important subsidies for riparian consumers. We systematically reviewed variations in the use of aquatic prey by riparian predators and investigated whether changes and differences in the availability of emerging insects influence riparian arthropod predator communities. We found that aquatic subsidies present a major food source for several riparian arthropod predators. However, the role of aquatic prey in the diet varied between predator groups and hunting strategies. Riparian web-building spiders, especially horizontal web-builders such as Tetragnatha, showed the highest proportion of aquatic insects in their diet (70 %). However, free-hunting spiders and riparian beetles also benefited substantially from these subsidies. The use of aquatic prey decreased with increasing distance from the water, varied throughout the year in line with the emergence peaks, and was affected by habitat characteristics. Our review also shows that the abundance and biomass of riparian arthropod predators can be influenced by variations in the availability of aquatic subsidies. This was particularly evident for riparian web-building spiders, especially horizontal web-building spiders such as Tetragnatha. Despite the considerable research activity over the past two decades, we identified several research gaps and present opportunities for future studies. First, there is a clear geographical bias, with a marked lack of studies in the Southern Hemisphere and Asia, with the exception of Japan. Second, most studies have focused on a few families of mostly web-building spiders while only a few have considered spiders with different hunting modes (e.g., ambush hunters or free hunters on vegetation), carabids and other beetles. Third, most studies used stable isotope analysis (SIA) for prey analysis. Additional methods, such as polyunsaturated fatty acid (PUFA) analysis, molecular gut content analysis, or combinations of these methods with SIA, should give a clearer picture of the reliance of riparian arthropods on aquatic prey
Kostråd i praktiken
Get PDFVåra matval får stora konsekvenser för folkhälsan, livsmedelssystemets hållbarhet, och i förlängningen också landets beredskap inför kriser. Kostråden pekar ut riktningen för hur vi bör äta för hälsan och miljön. Men mat är också kultur och känslor. Om kostråden ska få genomslag måste de förankras i människors vardag, kultur och sammanhang
Functional Characterization of a Female-Biased Chemoreceptor of the Codling Moth (Cydia pomonella) Responding to Aldehydes and Other Volatile Compounds
Get PDFWith the advent of semiochemical-based control strategies used to mitigate damage of agricultural pest moths, many studies have focused on the function of male-specific putative pheromone receptors (PRs). In this investigation, we instead isolated, heterologously expressed, and functionally characterized a female-biased candidate PR, CpomOR22, from the codling moth, Cydia pomonella. Using transgenic Drosophila melanogaster for single sensillum recording (SSR) and gas-chromatographic SSR, we tested both synthetic ligands and various apple headspace extracts, identifying saturated and unsaturated aldehydes (nonanal, decanal, undecanal, dodecanal; (Z)-4-undecenal and (Z)-6-undecenal) among the most active ligands. Parallel experiments expressing CpomOR22 in Xenopus oocytes confirmed the binding of nonanal, decanal and undecanal and revealed lactones (gamma-undecalactone and delta-dodecalactone) and several carboxylic acids as additional active compounds. The renowned ecological importance of aldehydes for the codling moth and the potential for newly identified ligands, such as lactones, may inform innovative control strategies based on novel semiochemicals to interfere with the female-specific chemosensory systems of this insect