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1.
Land consumption due to residential development, economic growth and transportation belongs to the most serious environmental pressures on landscapes worldwide, in particular in urbanised areas. Accordingly, the aim of containing the development of land is rated increasingly high on the agenda of environmental policy, at least in densely populated countries such as Germany, Belgium, the Netherlands or the UK. As a result, different strategies and instruments to prevent excessive land consumption are being discussed. However, many of these strategies and instruments adopt a rather general approach, while it seems more effective to define the particular areas where the goal of reducing land consumption is to be pursued. Such an approach must draw on information about how detrimental specific land use transitions are with regard to, for instance, the functionality of soils, water balance or habitat quality at specific locations. This paper introduces a conceptual framework for the impact assessment of land use transition in urban areas which highlights how such information can be acquired. This framework includes the differentiation of two levels of impact assessment: the level of the single land unit and the context level which takes into account regional and aggregated impacts of land use transition bound to the spatial context. The conceptual framework provides a basis to disaggregate (supra-)national policy targets regarding land use, to scale them down to the regional level, and thus to clarify the spatially explicit implications of land use policies.  相似文献   

2.
The Biodiversity Strategy of the European Union includes a target to “ensure no-net-loss of biodiversity and ecosystem services by 2020”. Many policy options can be envisioned to achieve such a no-net-loss target, mainly acting on land use and land management. To assess the effectiveness of such policies at a European Union (EU) scale, we simulated land use changes and their impacts on biodiversity and ecosystem services indicators. We analysed a Business–as-Usual scenario, and three no-net-loss scenarios. The no-net-loss scenarios included measures that aim to reduce negative impacts of land use change on biodiversity and ecosystem services, by better implementation of existing biodiversity conservation measures (Scenario 1); and enhancement of existing measures (Scenario 2); and offsetting residual impacts on areas of high biodiversity and ecosystem service value (Scenario 3).Results show that none of the scenarios achieved overall no-net-loss. Compared to a Business-as-Usual scenario, the no-net-loss scenarios reduced the overall degree of land cover change at EU level, hence reducing impacts on biodiversity and ecosystem services in large parts of the EU. The more comprehensive no-net-loss scenarios resulted in a gain of natural land cover. Moreover, natural areas became better connected, especially in peri-urban areas as a result of impact avoidance and offsetting. Richness of farmland bird species was projected to increase. Measures included in the no-net-loss scenarios had net positive effects on pollination and carbon sequestration, neutral effects on crop production, erosion prevention and flood regulation, and negative effects on nature-based recreation, compared to Business-as-Usual. In particular circumstances policy measures invoked displacement effects in land use allocation, reducing the effectiveness of the measures. This was primarily the case for flood regulation services throughout the EU.This study differentiates the potential effectiveness of a no-net-loss policy framework in three manners: (i) considering biodiversity and ecosystem services simultaneously; (ii) in the light of existing policies and land use pressures; and (iii) in different land use contexts across the EU. Taken together, we conclude that achieving no-net-loss for biodiversity and ecosystem services throughout the EU remains challenging given high land use demands. Nevertheless, in large parts of Europe there appears room for improvement for certain kinds of biodiversity and ecosystem services compared to Business-as-Usual, while still meeting other land use demands.  相似文献   

3.
This article demonstrates how the future of Kinshasa, the capital of the Democratic Republic of Congo is partly to be found in its past. It looks at the complex and often ambivalent role many autochthonous land chiefs continue to play in the processes of urban expansion currently taking place in Kinshasa.  相似文献   

4.
To redress past racial discrepancies in ownership and tenure, the ANC government of South Africa initiated programmes to make land accessible to the previously disadvantaged. A key component of the national land reform programme was the provision of commonage lands to urban municipalities for use by the urban poor. However, there has been no assessment of the contribution that urban commonage makes to previously disadvantaged households. This study assessed the economic benefits of the commonage programme to local households, through an in-depth survey of 90 households across three small towns in the Eastern Cape of South Africa. We examined the marketed and non-marketed consumptive direct-use values of land-based livelihoods on commonage, calculated via the ‘own reported values’ approach. The results indicate that a proportion of South Africa's urban population rely to some degree on municipal commonage for part of their livelihoods. Commonage contributions to total livelihood incomes ranged between 14 and 20%. If the contributions from commonage were excluded, the incomes of over 10% of households in each study town would drop below the poverty line. Overall, the value of harvests from commonage was worth over R1 000 (US$ 142) per hectare per year and over R4.7 million (US$ 0.68 million) per commonage per year. However, the extent and nature of use and reliance was not uniform among households, so that we developed a typology of commonage users, with four types being identified. However, rapidly growing urban populations and high levels of poverty potentially threaten the sustainability of commonage resource use. Yet the national land reform programme focuses largely on the transfer of land to municipalities and not on sustainable management. Municipalities, in turn, invest relatively little in commonage management, and the little they do is focussed on livestock production. Non-timber forest products are not considered at all, even though this study shows that they are a vital resource for the urban poor, notably for energy and construction materials.  相似文献   

5.
Globally, there is growing demand for increased agricultural outputs. At the same time, the agricultural industry is expected to meet increasingly stringent environmental targets. Thus, there is an urgent pressure on the soil resource to deliver multiple functions simultaneously. The Functional Land Management framework (Schulte et al., 2014) is a conceptual tool designed to support policy making to manage soil functions to meet these multiple demands. This paper provides a first example of a practical application of the Functional Land Management concept relevant to policy stakeholders. In this study we examine the trade-offs, between the soil functions ‘primary productivity’ and ‘carbon cycling and storage’, in response to the intervention of land drainage systems applied to ‘imperfectly’ and ‘poorly’ draining managed grasslands in Ireland. These trade-offs are explored as a function of the nominal price of ‘Certified Emission Reductions’ or ‘carbon credits’. Also, these trade-offs are characterised spatially using ArcGIS to account for spatial variability in the supply of soil functions.To manage soil functions, it is essential to understand how individual soil functions are prioritised by those that are responsible for the supply of soil functions – generally farmers and foresters, and those who frame demand for soil functions – policy makers. Here, in relation to these two soil functions, a gap exists in relation to this prioritisation between these two stakeholder groups. Currently, the prioritisation and incentivisation of these competing soil functions is primarily a function of CO2 price. At current CO2 prices, the agronomic benefits outweigh the monetised environmental costs. The value of CO2 loss would only exceed productivity gains at either higher CO2 prices or at a reduced discount period rate. Finally, this study shows large geographic variation in the environmental cost: agronomic benefit ratio. Therein, the Functional Land Management framework can support the development of policies that are more tailored to contrasting biophysical environments and are therefore more effective than ‘blanket approaches’ allowing more specific and effective prioritisation of contrasting soil functions.  相似文献   

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