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Optimizing Species Richness in Mosaic Landscapes : A Probabilistic Model of Species-Area Relationships

Most landscapes are comprised of multiple habitat types differing in the biodiversity they contain. This is certainly true for human modified landscapes, which are often a mix of habitats managed with different intensity, semi-natural habitats and even pristine habitats. To understand fundamental questions of how the composition of such landscapes affects biodiversity conservation, and to evaluate

Ecological traits interact with landscape context to determine bees' pesticide risk

Widespread contamination of ecosystems with pesticides threatens non-target organisms. However, the extent to which life-history traits affect pesticide exposure and resulting risk in different landscape contexts remains poorly understood. We address this for bees across an agricultural land-use gradient based on pesticide assays of pollen and nectar collected by Apis mellifera, Bombus terrestris

Drip irrigation improves spring wheat water productivity by reducing leaf area while increasing yield

To mitigate the climate change-induced water shortage and realize the sustainable development of agriculture, drip irrigation, a more efficient water-saving irrigation method, has been intensively implemented in most arid agricultural regions in the world. However, compared to traditional border irrigation, how drip irrigation affects the biophysical conditions in the cropland and how crops physio

Seasonal variation in biogenic volatile organic compound (BVOC) emissions from Norway spruce in a Swedish boreal forest

Terpene emissions from the top-canopy layer (at 20 m) of one 118-year-old Norway spruce tree were measured between June and September 2013 using a branch chamber. Total terpene emissions varied from 0.05 to 332.5 μg gdw -1 h-1 with a peak in August. Monoterpenes dominated throughout the summer and on average accounted for 65% of the total terpene mass, followed by sesquiterpenes (29%) and isoprene

Crop management affects pollinator attractiveness and visitation in oilseed rape

Ecological intensification of agriculture implies managing ecological processes to improve performance of agricultural systems. However, impacts on relevant ecological functions such as insect pollination from other crop management factors are poorly explored. Pest insects and crop resources such as water availability can directly affect crop yields, but it is unknown if there are indirect effects

A model to account for data dependency when estimating floral cover in different land use types over a season

We propose a model to consider data dependencies and assess spatial and temporal variability in land use specific floral coverage across landscapes. Data dependence arising from repeated measurements across the flowering season is taken into account using hierarchical Archimedean copulas, where the correlation is assumed to be stronger within seasonal periods than between periods. For each seasona

Assessing the risk of stigma clogging in strawberry flowers due to pollinator sharing with oilseed rape

Strawberry and oilseed rape are economically important and co-flowering insect-pollinated crops that may affect each other via shared pollinators. One potential negative effect of pollinator sharing is stigma clogging, i.e. that pollen from one plant species covers the stigma and prevents pollination in the other. We tested if application of oilseed rape pollen on strawberry receptacles reduces po

Assessing critical loads for nitrogen under climate change based on chemical and biological indicators in a sub-Arctic country : The case of Sweden

The integrated dynamic ecosystem models SAFE and ForSAFEVEG were used to estimate critical loads for nitrogen using different chemical and biological criteria, and attempting to account for possible effects of climate change. The study is based on a model application on a set of 640 sites earlier used for critical loads assessments in Sweden, focusing on the ecological effect of nitrogen pollution

Critical biomass harvesting – Applying a new concept for Swedish forest soils

The contribution of forest harvesting to base cation losses and soil acidification has increased in recent years in Sweden, as the demand for bioenergy has increased and the sulphur deposition has decreased. Thus, new policy tools are required to evaluate the progress of the recovery from acidification, and as a basis for forest management recommendations. In this study we introduce and test a con

Changes of community composition at multiple trophic levels due to hunting in Nigerian tropical forest

Hunting in tropical forests decimates large mammals, and this may have direct and indirect effects on other trophic levels and lead to trophic cascades. We compared replicated sites of hunted and protected forests in southeastern Nigeria, with respect to community composition of primates, other mammals, birds, plant seedlings, and mature trees. We make predictions regarding the community compositi

The relation between oilseed rape and pollination of later flowering plants varies across plant species and landscape contexts

Increasing cultivation of oilseed rape may have consequences for pollinators and wild plant pollination. By providing pollinating insects with pollen and nectar, oilseed rape benefits short-tongued, generalist insect species. Long-tongued bumble bee species, specialized to other flower types, may instead be negatively affected by increased competition from the generalists (e.g. due to nectar-robbi

Ignoring Ecosystem-Service Cascades Undermines Policy for Multifunctional Agricultural Landscapes

Over and above food, agricultural landscapes provide citizens with crucial public-good ecosystem services, such as biodiversity conservation, cultural values, recreational opportunities, and food security. Because continuing agricultural intensification undermines the ability of landscapes to provide public goods, policies have been implemented to preserve landscape multifunctionality, but with li