An assessment of silvopastoral systems condition and their capacity to generate ecosystem services in the Colombian Amazon

Livestock production in the Colombian Amazonia is typically dual-purpose (meat and milk) based on silvopastoral systems. We aimed to assess how the ecological condition of these systems correspond to the ecosystem services they generate based on an assessment of farmers’ knowl-edge of the tree species. We evaluated 159 paddocks. We recorded 143 tree species from 37 families, with 22 species being most common (relative occurrence frequency = 57%). Based on tree species composition, we characterized four states of silvopastoral condition (hereon ‘pad-dock condition types’) using clustering techniques: (i) High structural complexity and highest tree species richness (HSCR); (ii) High species diversity and tall trees (HDTT); (iii) High species diversity and medium-sized trees (HDMT); (iv) Structurally simple with lowest species richness (SSLR). Tree species richness was significantly higher in HSCR (11.70 ± 1.47 per paddock), than in SSLR (2.86 ± 0.80). HDTT and HDMT had similar richness, with intermediate values (5.55 ± 0.82 and 6.38 ± 0.51, respectively). Farmers appreciate a number of ecosystem services provided by the silvopastoral system, but a limited number of tree species are valued. This indicates the need for additional biodiversity conservation measures in these landscapes, including measures to improve knowl-edge about the value of tree species with few occurrences or low densities. Tree species richness; silvopastoral system condition; biodiversity conservation; Importance Value Index; Index of Cultural Importance; tree selective preservationpublishedVersio

The contributions of flower strips to wild bee conservation in agricultural landscapes can be predicted using pollinator habitat suitability models

1. Sowing flower strips along field edges is a widely adopted method for conserving pollinating insects in agricultural landscapes. To maximize the effect of flower strips given limited resources, we need spatially explicit tools that can prioritize their placement, and for identifying plant species to include in seed mixtures. 2. We sampled bees and plant species as well as their interactions in a semicontrolled field experiment with roadside/field edge pairs with/without a sown flower strip at 31 sites in Norway and used a regional spatial model of solitary bee species richness to test if the effect of flower strips on bee species richness was predictable from the modelled solitary bee species richness. 3. We found that sites with flower strips were more bee species rich compared to sites without flower strips and that this effect was greatest in areas that the regional solitary bee species richness model had identified to be particularly important for bees. Spatial models revealed that even within small landscapes there were pronounced differences between field edges in the predicted effect of sowing flower strips. 4. Of the plant species that attracted the most bee species, the majority mainly attracted bumblebees and only few species also attracted solitary bees. Considering both the taxonomic diversity of bees and the species richness of bees attracted by plants we suggest that seed mixes containing Hieracium spp. such as Hieracium umbellatum, Pilosella officinarum, Taraxacum spp., Trifolium repens, Lotus corniculatus, Stellaria graminea and Achillea millefolium would provide resources for diverse bee communities in our region 5. Spatial prediction models of bee diversity can be used to identify locations where flower strips are likely to have the largest effect and can thereby provide managers with an important tool for prioritizing how funding for agri-environmental schemes such as flower strips should be allocated. Such flower strips should contain plant species that are attractive to both solitary and bumblebees, and do not need to be particularly plant species rich as long as the selected plants complement each other. agri-environmental schemes, bees, flower strips, networks, pollinators, restoration, spatialpublishedVersio

Climatic conditions and landscape diversity predict plant–beeinteractions and pollen deposition in bee-pollinated plants

Climate change, landscape homogenization, and the decline of beneficial insectsthreaten pollination services to wild plants and crops. Understanding how pollinationpotential (i.e. the capacity of ecosystems to support pollination of plants) is affectedby climate change and landscape homogenization is fundamental for our ability topredict how such anthropogenic stressors affect plant biodiversity. Models of pollina-tor potential are improved when based on pairwise plant–pollinator interactions andpollinator’s plant preferences. However, whether the sum of predicted pairwise interac-tions with a plant within a habitat (a proxy for pollination potential) relates to pollendeposition on flowering plants has not yet been investigated. We sampled plant–beeinteractions in 68 Scandinavian plant communities in landscapes of varying land-coverheterogeneity along a latitudinal temperature gradient of 4–8°C, and estimated pollendeposition as the number of pollen grains on flowers of the bee-pollinated plants Lotuscorniculatus and Vicia cracca. We show that plant–bee interactions, and the pollinationpotential for these bee-pollinated plants increase with landscape diversity, annual meantemperature, and plant abundance, and decrease with distances to sand-dominatedsoils. Furthermore, the pollen deposition in flowers increased with the predicted pol-lination potential, which was driven by landscape diversity and plant abundance. Ourstudy illustrates that the pollination potential, and thus pollen deposition, for wildplants can be mapped based on spatial models of plant–bee interactions that incorpo-rate pollinator-specific plant preferences. Maps of pollination potential can be used toguide conservation and restoration planning. ecological networks, ecosystem service mapping, landscape diversity, plant–pollinator interactions, pollinationpublishedVersio

Seasonal variation in urban pollen resource use by north temperate European honeybees

Urban green infrastructure can provide important habitats for pollinators and support urban ecosystem services. Therefore, these areas must be managed to maximize biodiversity and density of pollinating insects. We used DNA metabarcoding to study honeybee pollen resource use over time and space in the city of Oslo, Norway, and to assess the role of green infrastructure as a resource for pollinators and the services they generate. Urban honeybees used diverse pollen resources throughout their active season. There was considerable seasonal turnover in pollen resource use that reflected flowering phenology. Non-native plants (including invasive species) were an important resource early in the season but were replaced by native plants later in the season. Hive location was not strongly correlated with resource use, likely indicating effective long-distance foraging in the fragmented urban landscape. However, flower visitation rates and floral resource density in public urban green spaces were coupled to pollen use. Honeybees collected pollen from a small number of preferred species but also visited other species, likely for nectar. To preserve pollinator services, urban planning should consider flower resource management, with particular focus on planting native species that can act as early season resources for bees. Public campaigns and other incentive mechanisms to promote the cultivation of native plants that are resources for pollinators and the protection of urban semi-natural habitats have the potential to enhance the value of green infrastructure to support urban pollinators and pollination services. Urban ecology · Pollination · Seasonality · Pollen diversity · Flower resources · Urban green infrastructure · Citizen sciencepublishedVersio

Undersøker samspillet mellom blåbær og humler i fjellet

© Norsk institutt for naturforskning. Publikasjonen kan siteres fritt med kildeangivelse

Undersøker samspillet mellom blåbær og humler i fjellet

© Norsk institutt for naturforskning. Publikasjonen kan siteres fritt med kildeangivelse