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23Aim: We investigated the patterns of autotrophic and heterotrophic relative species 24 richness along a total phosphorus (TP) concentration gradient. The relative species richness -25 TP relationships were calculated separately for four different regions [(sub)tropical, xeric, 26 temperate, and cold] and two types of water bodies (lakes and streams). 27 Location: Global 28Methods: Using data from peer-reviewed articles reporting the occurrence of 29 freshwater species at specific TP concentrations, we determined the species richness along a 30 TP gradient. Using log-logistic regressions, we then estimated the TP concentration at which 31 the potential decrease of relative species richness (RSR) equals 0.5 and the slope at which the 32 decrease occurs (β). The RSR is given as the ratio of species richness to maximized species 33 richness along a TP gradient. 34Results: The RSR of streams generally decreased more rapidly than that of lakes with 35 increasing P, as illustrated by the steeper slope of the log-logistic functions for streams (β lakes 36 < β streams ). Although there was no consistent trend between autotrophs and heterotrophs in the 37 different regions, we found that the TP concentration at which the RSR equals 0.5 was lower 38 in cold regions (0.04 -0.22 mg P/L) than in warmer regions (0.28 -1.29 mg P/L). 39Main conclusions: The log-logistic relationships between RSR and TP concentration 40 vary considerably among regions of the world, between freshwater types (lakes and streams) 41 and between species groups (autotrophs and heterotrophs). This variability may be attributed 42 to differences between the two freshwater types in respect to their species groups and 43 evolutionary patterns, nutrient demand, biogeochemical and hydrologic processes. We were 44 not able to derive log-logistic regressions for all combinations of freshwater type or species 45 type and region [e.g., (sub)tropical lakes]. For other areas, our results can be used to assess 46 the potential impact of phosphorus eutrophication on freshwater biota. 47 3

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Data on low dissolved oxygen (DO₂) tolerance of freshwater fish species of north-western Europe were used to create species sensitivity distributions (SSD). Lowest observed effect concentrations (LOEC) and 100% lethal concentrations (LC₁₀₀) data were collected from the scientific literature. Comparisons were made among life stages as well as between native and exotic species. In addition, lethal DO₂ concentrations were compared to oxygen concentrations corresponding to maximum tolerable water temperatures of the same species. Fish eggs and embryos were the least tolerant. Juveniles had a significantly lower mean LOEC than adults, but there was no difference in mean LC₁₀₀ between the two groups. The difference in lethal oxygen concentrations between adults and juveniles was largest for three salmonids, although it remains uncertain if this was a result of smoltification. There were no significant differences between native and exotic species; however, data on exotics are limited. DO₂ concentrations converted from maximum tolerable water temperatures were 3·9 times higher than the measured lethal DO₂ concentrations, which may reflect changes in respiration rates (Q₁₀) and may also relate to the simplicity of the model used.

Purpose Change of vegetation cover and increased land use intensity, particularly for agricultural use, can affect species richness. Within life cycle impact assessment, methods to assess impacts of land use on a global scale are still in need of development. In this work, we present a spatially explicit data-driven approach to characterize the effect of agricultural land occupation on different species groups. Methods We derived characterization factors for the direct impact of agricultural land occupation on relative species richness. Our method identifies potential differences in impacts for cultivation of different crop types, on different species groups, and in different world regions. Using empirical species richness data gathered via an extensive literature search, characterization factors were calculated for four crop groups (oil palm, low crops, Pooideae, and Panicoideae), four species groups (arthropods, birds, mammals, and vascular plants), and six biomes. Results and discussion Analysis of the collected data showed that vascular plant richness is more sensitive than the species richness of arthropods to agricultural land occupation. Regarding the differences between world regions, the impact of agricultural land use was lower in boreal forests/taiga than in temperate and tropical regions. The impact of oil palm plantations was found to be larger than that of Pooideae croplands, although we cannot rule out that this difference is influenced by the spatial difference between the oil palm-and Pooideaegrowing regions as well. Analysis of a subset of data showed that the impact of conventional farming was larger than the impact of low-input farming. Conclusions The impact of land occupation on relative species richness depends on the taxonomic groups considered, the climatic region, and farm management. The influence of crop type, however, was found to be of less importance.

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The global demand for biofuels in the transport sector may lead to significant biodiversity impacts via multiple human pressures. Biodiversity assessments of biofuels, however, seldom simultaneously address several impact pathways, which can lead to biased comparisons with fossil fuels. The goal of the present study was to quantify the direct influence of habitat loss, water consumption and greenhouse gas (GHG) emissions on potential global species richness loss due to the current production of first‐generation biodiesel from soybean and rapeseed and bioethanol from sugarcane and corn. We found that the global relative species loss due to biofuel production exceeded that of fossil petrol and diesel production in more than 90% of the locations considered. Habitat loss was the dominating stressor with Chinese corn, Brazilian soybean and Brazilian sugarcane having a particularly large biodiversity impact. Spatial variation within countries was high, with 90th percentiles differing by a factor of 9 to 22 between locations. We conclude that displacing fossil fuels with first‐generation biofuels will likely negatively affect global biodiversity, no matter which feedstock is used or where it is produced. Environmental policy may therefore focus on the introduction of other renewable options in the transport sector.