Suchergebnisse

Research into social and spatial segregation in urban areas has a very long tradition in the Anglo-Saxon geography. Even after the 2000s only a few researchers have turned to the non-Western countries to understand and explain segregation in different geographies. As a country in-between the East and the West, in Turkey, where segregation reveals itself in many forms there are very few studies dealing directly with the question of segregation. The article thus deems it crucial to shed light on a rarely-known geography in terms of residential and socio-economic segregation practices focusing on a larger Anatolian geography. Key findings show that as far as residential segregation is concerned among socio-economic status groups, Turkish cities have a characteristic pattern where the highest and the lowest status groups never share a common border in urban areas. But, it is also seen that socio-economic groups behind this common pattern exhibit completely different characteristics.

This paper reports on the first quantitative study of the diet of macaroni and rockhopper penguins
(Eudytes chrysolophus and E. chrysocome) undertaken on sub-Antarctic Heard Island. Stomach contents
were sampled during the late incubation and early chick-rearing phase. Both penguin species generally
fed on euphausiids and fish, albeit in different proportions and frequently on different species and
sizes. In particular, macaroni penguins consumed considerably more fish on a per cent mass basis
(23.2 v. 8.0%), selecting larger sized prey than rockhopper penguins did. It is hypothesised that these
dietary differences provide macaroni penguins with a broader feeding niche leading to a greater
availability of food and are thus an important factor contributing to the numerical dominance of
macaroni penguins on the island.

This project has received funding from the European Research Council under the European Union's Horizon 2020 Research and Innovation Programme (Grant 678812 to M.W.C.). J.S. also acknowledges support from the China Scholarship Council (CSC). ; With annual precipitation less than 20 mm and extreme UV intensity, the Atacama Desert in northern Chile has long been utilized as an analogue for recent Mars. In these hyperarid environments, water and biomass are extremely limited, and thus, it becomes difficult to generate a full picture of biogeochemical phosphate‐water dynamics. To address this problem, we sampled soils from five Atacama study sites and conducted three main analyses—stable oxygen isotopes in phosphate, enzyme pathway predictions, and cell culture experiments. We found that high sedimentation rates decrease the relative size of the organic phosphorus pool, which appears to hinder extremophiles. Phosphoenzyme and pathway prediction analyses imply that inorganic pyrophosphatase is the most likely catalytic agent to cycle P in these environments, and this process will rapidly overtake other P utilization strategies. In these soils, the biogenic δ18O signatures of the soil phosphate (δ18OPO4) can slowly overprint lithogenic δ18OPO4 values over a timescale of tens to hundreds of millions of years when annual precipitation is more than 10 mm. The δ18OPO4 of calcium‐bound phosphate minerals seems to preserve the δ18O signature of the water used for biogeochemical P cycling, pointing toward sporadic rainfall and gypsum hydration water as key moisture sources. Where precipitation is less than 2 mm, biological cycling is restricted and bedrock δ18OPO4 values are preserved. This study demonstrates the utility of δ18OPO4 values as indicative of biogeochemical cycling and hydrodynamics in an extremely dry Mars‐analogue environment. ; Publisher PDF ; Peer reviewed

International audience ; This paper aims at analyzing the role of an environmental tax or an environmental subsidy as instruments for preserving phosphate reserves, for improving water quality by reducing eutrophication, and for increasing social welfare. Toward these goals, we use a duopoly model "à la Stack- elberg", assume the presence of a benevolent government that takes into account the bene.cial e¤ect of recycling in the social welfare function and refunds the revenue of the tax to the society. First, we .nd that taxing extracted phosphorus or subsidizing recycled phosphorus contributes to the postponement of the depletion of the resource and to the reduction of eutrophication. Second, we .nd that taxing extracted phosphorus reduces consumers.surplus, whereas subsidizing recycled phosphorus increases it. Third, we show that the subsidy set by the regulator is higher than the marginal bene.t of recycling, whereas the level of the tax with respect to the marginal social damage of pollution is ambiguous. Fourth, we state that the tax and the subsidy increase social welfare. Fifth, by way of com- parison, we .nd that if the regulator aims at saving phosphorus, reducing eutrophication and improving social welfare simultaneously, subsidizing recycled phosphorus is the best policy, but if he aims only at saving phos- phorus and reducing eutrophication, taxing extracted phosphorus is more optimal than subsidizing recycled phosphorus.

International audience ; This paper aims at analyzing the role of an environmental tax or an environmental subsidy as instruments for preserving phosphate reserves, for improving water quality by reducing eutrophication, and for increasing social welfare. Toward these goals, we use a duopoly model "à la Stack- elberg", assume the presence of a benevolent government that takes into account the bene.cial e¤ect of recycling in the social welfare function and refunds the revenue of the tax to the society. First, we .nd that taxing extracted phosphorus or subsidizing recycled phosphorus contributes to the postponement of the depletion of the resource and to the reduction of eutrophication. Second, we .nd that taxing extracted phosphorus reduces consumers.surplus, whereas subsidizing recycled phosphorus increases it. Third, we show that the subsidy set by the regulator is higher than the marginal bene.t of recycling, whereas the level of the tax with respect to the marginal social damage of pollution is ambiguous. Fourth, we state that the tax and the subsidy increase social welfare. Fifth, by way of com- parison, we .nd that if the regulator aims at saving phosphorus, reducing eutrophication and improving social welfare simultaneously, subsidizing recycled phosphorus is the best policy, but if he aims only at saving phos- phorus and reducing eutrophication, taxing extracted phosphorus is more optimal than subsidizing recycled phosphorus.

International audience ; This paper aims at analyzing the role of an environmental tax or an environmental subsidy as instruments for preserving phosphate reserves, for improving water quality by reducing eutrophication, and for increasing social welfare. Toward these goals, we use a duopoly model "à la Stack- elberg", assume the presence of a benevolent government that takes into account the bene.cial e¤ect of recycling in the social welfare function and refunds the revenue of the tax to the society. First, we .nd that taxing extracted phosphorus or subsidizing recycled phosphorus contributes to the postponement of the depletion of the resource and to the reduction of eutrophication. Second, we .nd that taxing extracted phosphorus reduces consumers.surplus, whereas subsidizing recycled phosphorus increases it. Third, we show that the subsidy set by the regulator is higher than the marginal bene.t of recycling, whereas the level of the tax with respect to the marginal social damage of pollution is ambiguous. Fourth, we state that the tax and the subsidy increase social welfare. Fifth, by way of com- parison, we .nd that if the regulator aims at saving phosphorus, reducing eutrophication and improving social welfare simultaneously, subsidizing recycled phosphorus is the best policy, but if he aims only at saving phos- phorus and reducing eutrophication, taxing extracted phosphorus is more optimal than subsidizing recycled phosphorus.

This paper aims at analyzing the role of an environmental tax or an environmental subsidy as instruments for preserving phosphate reserves, for improving water quality by reducing eutrophication, and for increasing social welfare. Toward these goals, we use a duopoly model "à la Stack- elberg", assume the presence of a benevolent government that takes into account the bene.cial e¤ect of recycling in the social welfare function and refunds the revenue of the tax to the society. First, we .nd that taxing extracted phosphorus or subsidizing recycled phosphorus contributes to the postponement of the depletion of the resource and to the reduction of eutrophication. Second, we .nd that taxing extracted phosphorus reduces consumers.surplus, whereas subsidizing recycled phosphorus increases it. Third, we show that the subsidy set by the regulator is higher than the marginal bene.t of recycling, whereas the level of the tax with respect to the marginal social damage of pollution is ambiguous. Fourth, we state that the tax and the subsidy increase social welfare. Fifth, by way of com- parison, we .nd that if the regulator aims at saving phosphorus, reducing eutrophication and improving social welfare simultaneously, subsidizing recycled phosphorus is the best policy, but if he aims only at saving phos- phorus and reducing eutrophication, taxing extracted phosphorus is more optimal than subsidizing recycled phosphorus.