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161.
162.
The main objective of the European Water Framework Directive (WFD) is the achievement of a good ecological and chemical status of the water environment (water bodies). This status corresponds to the limit value of Germany's Working Group of the Federal States on Water Problems Issues (LAWA) for water quality class II (3 mg/l total nitrogen). The rivers in the intensively cropped Upper Ems River basin (northwestern Germany) show total nitrogen concentrations in excess of 5–10 mg/l. Hence, the objective of our study was to find a land use and land management scenario that would reduce the total nitrogen concentration to meet the WFD requirements for good ecological and chemical status. We developed consecutive land use and management scenarios on the basis of policy instruments such as the support of agro-environmental measures by Common Agricultural Policy and regional landscape development programs. The model simulations were done by using the Soil and Water Assessment Tool (SWAT). Results of SWAT scenario calculations showed that drastic measures, which are unrealistic from a socio-economic point of view, would be needed to achieve the water quality target in the basin (reduction of arable land from 77.2% to 46% [13% organic farming], increase of pasture from 4% to 15%, afforestation from 10% to 21%, increase of protected wetlands from 0% to 9%, etc.). The example shows additionally that the achievement of the WFD targets is only possible with a consideration of regional landscape and land use distinctions. A related problem yet to be addressed is the general lack of measured water quality data with which to calibrate and validate water quality models such as SWAT. This adds considerable uncertainty to already complicated and uncertainty situations. Thus, improved strategies for water quality monitoring, and data accessibility must be established.  相似文献   
163.
A recent paper by Hardaker et al. (The Australian Journal of Agricultural and Resource Economics, 48, 2004a, 253) and book by Hardaker et al. (Coping with Risk in Agriculture, 2004b) describe a procedure for determining an efficient set from among a set of random alternatives. This procedure, called stochastic efficiency with respect to a function (SERF), is claimed to make the same assumption concerning the risk aversion measures as does stochastic dominance with respect to a function (SDRF). This is claim is incorrect. SERF imposes an additional requirement on the risk aversion measures of the decision makers. Both procedures assume a lower and an upper bound on risk aversion, but SERF also assumes that all risk aversion measures are of the same functional form as these lower and upper bound functions. This additional strong requirement on risk preferences implies that the efficient set identified under SERF is usually smaller than that identified using SDRF.  相似文献   
164.
The authors examine antecedents and consequences of environmental stewardship in frontline business-to-business teams. On the basis of data from members of 34 teams organized into regional networks, they demonstrate the differential impact of team environmental stewardship on customer satisfaction ratings and sales. Furthermore, the results reveal lagged individual-level effects of autonomy and supervisory support on environmental stewardship, as well as lagged group-level effects of past performance. Finally, dispersion models of team stewardship differentially moderate antecedent–stewardship relationships. Whereas within-team consensus strengthens the impact of past satisfaction ratings on subsequent stewardship, between-team consensus weakens the negative impact of past sales.  相似文献   
165.
Recent empirical assessments revealed that footprint indicators calculated with various multi-regional input–output (MRIO) databases deliver deviating results. In this paper, we propose a new method, called structural production layer decomposition (SPLD), which complements existing structural decomposition approaches. SPLD enables differentiating between effects stemming from specific parts in the technology matrix, e.g. trade blocks vs. domestic blocks, while still allowing to link the various effects to the total region footprint. Using the carbon footprint of the EU-28 in 2011 as an example, we analyse the differences between EXIOBASE, Eora, GTAP and WIOD. Identical environmental data are used across all MRIO databases. In all model comparisons, variations in domestic blocks have a more significant impact on the carbon footprint than variations in trade blocks. The results provide a wealth of information for MRIO developers and are relevant for policy makers designing climate policy measures targeted to specific stages along product supply chains.  相似文献   
166.
The article examines the effect of membership in farmer groups (MFG) on adoption lag of agricultural technologies and farm performance in Burundi, the Democratic Republic of Congo and Rwanda. We use duration and stochastic production frontier models on farm household data. We find that the longer the duration of MFG, the shorter the adoption lag and much more so if combined with extension service delivery. Farmer groups function as an important mechanism for improving farm productivity through reduced technical inefficiency in input use. We discuss policy implications under which farmer groups are a useful channel to reduce adoption lag, and the means through which improved farm performance can be achieved.  相似文献   
167.
As taxpayers typically pay relatively little attention to low levels of inflation induced income tax bracket creep, policy makers tend to regularly postpone correction of this problem. Eventually, however, the fiscal illusion fades away, and political pressure for tax relief arises once the cumulative increase of the average tax rate exceeds a critical threshold. Using Germany as an example, it is shown that bracket creep can provoke revenue cycles in public budgets that hinder governments’ compliance with the numerical budget rules. An indexation of the tax tariff, which would provide an automatic correction for bracket creep, could prevent such fluctuations and thus provide a favourable framework for the debt brake.  相似文献   
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169.
This study uses resource‐based measures to explore the evolution of China's demand and supply for food. China's dietary shift from plant to animal‐based foods, induced by its income growth, is likely to impose considerable pressure on agricultural resources. China's demand for food on this measure appears consistent with global trends, while China is an out‐performer on the supply side, producing much more food than its income level and land endowment would predict. China's current per capita income is in a range where consumption growth is high and in excess of production growth, but the gap between supply and demand is likely to diminish as population and per capita consumption growth decelerate. Continuing agricultural productivity growth and sustainable resource management will be important influences on the growth of China's future net import demand for food.  相似文献   
170.
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