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Eutrophication assessments in water management to quantify nutrient loads and identify mitigating measures seldom include the contribution from horse facilities. This may be due to lack of appropriate methods, limited resources, or the belief that the impact from horses is insignificant. However, the recreational horse sector is growing, predominantly in multi-functional peri-urban landscapes. We applied an ecosystem management approach to quantify nutrient loads from horse facilities in the Stockholm Region, Sweden. We found that horses increased the total loads with 30–40% P and 20–45% N, with average area-specific loads of 1.2 kg P and 7.6 kg N ha−1 year−1. Identified local risk factors included manure management practices, trampling severity, soil condition and closeness to water. Comparisons of assessment methods showed that literature standard values of area-specific loads and water runoff may be sufficient at the catchment level, but in small and more complex catchments, measurements and local knowledge are needed. [ABSTRACT FROM AUTHOR]

In fragmented farmland landscapes structural complexity and low agricultural intensification should decrease the abundance of crop aphids due to increased abundances and species diversity of aphid enemies, including hymenopteran parasitoids. Here we study the effects of landscape structure and agricultural intensification on parasitism rates, abundances, and species richness of aphids and their parasitoids in five different regions in Europe. While total aphid numbers did not differ significantly among regions, we observed marked differences between Scandinavian and central European sites with respect to the species composition of aphids and their parasitoids and parasitism rates. In the cross country comparison landscape complexity and agricultural intensification did not significantly affect total aphid densities, although we observed species-specific reactions to land use. We also observed a tendency towards increased parasitoid species richness at low agricultural intensification but not at high landscape structure. [ABSTRACT FROM AUTHOR]

Agri-environment schemes (AES) have been established to counteract negative effects of agricultural intensification on e.g. semi-natural pastures and meadows. The efficiency of most AESs have, however, been poorly evaluated. We evaluated the success of a Swedish AES for the management of semi-natural pastures by comparing species richness and composition of vascular plants (except trees), epiphytic lichens and trees among pastures receiving higher (high value pastures) and lower levels of AES paymens (general value pastures). There was no difference in the number of tree species among high and general value pastures, even though AES regulations allow a maximum of 60 and 100 trees/ha in general and high value pastures, respectively. High value pastures had, however, a higher number of plant and epiphytic lichen species than common value pastures. Moreover, a higher number of pasture specialist plant species were indicative of high value pastures than of general value pastures. No lichen species indicating high value pastures are associated with habitats with low canopy cover (such as e.g. pastures). Finally, tree identity was an important factor for explaining the number and composition of epiphytic lichen species. Our study highlights that species groups can respond differently to agri-environment schemes and other conservation measures. Even though the effects are the desired on the diversity of one assessed taxon, this is not always the case for non-target organism groups. [ABSTRACT FROM AUTHOR]

Agricultural intensification may result in important shifts in insect community composition and function, but this remains poorly explored. Studying how groups of species with shared traits respond to local and landscape scale land-use management can reveal mechanisms behind such observed impacts. We tested if ground beetles (Coleoptera: Carabidae) divided into trait groups based on body sizes, wing morphologies and dietary preferences respond differently to farming practise (organic and conventional), farming intensity (measured as yield) and landscape complexity (measured as the proportion of arable land within a 1,000 m radius) across Europe. We used data from 143 farms in five regions in northern and central Europe. Organic farms did not differ in abundance or richness of any trait group compared to conventional farms. As farm scale intensity (yield) increased, overall abundance of beetles decreased, but abundances of small and medium sized beetles, as well as that of wingless beetles, were unaffected. Overall species richness was not affected by yield, whereas consideration of traits revealed that phytophagous and omnivorous beetles were less species rich on farms with high yields. Increasing the proportion of arable land in the landscape increased overall beetle abundance. This was driven by an increase in omnivorous beetles. The total species richness was not affected by an increase in the proportion arable land, although the richness of wingless beetles was found to increase. Potential effects on ecosystem functioning need to be taken into account when designing schemes to maintain agricultural biodiversity, because species with different ecological traits respond differently to local management and landscape changes. [ABSTRACT FROM AUTHOR]