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251.
Colette S. Vogeler Johanna Hornung Nils C. Bandelow 《Journal of Environmental Policy & Planning》2020,22(4):518-530
ABSTRACT Sustainable agriculture implies trade-offs with farm animal welfare. Proposals to increase agricultural productivity and ecological sustainability alike, are often linked to intensification, which may restrict animal welfare. Despite the growing importance of farm animal welfare for the alignment of agricultural and environmental policy, determinants of decision-making at the EU level remain unexplored. This article contributes to closing this research gap, broadening our understanding of why policymakers vote for the enactment of animal welfare policies. Applying the Social Identities in the Policy Process (SIPP) perspective we highlight the role of group membership for individual decision-making. By means of a quantitative analysis of voting behaviour in the European Parliament on two animal welfare policies, we show that different identities are salient. The strongest predictor is political group membership. In case of defections from the group line, the salience of national, sectoral and also demographic identities adds to the understanding of decision-making. 相似文献
252.
Strategies to overcome barriers to the development of sustainable agriculture in Canada: The role of agribusiness 总被引:1,自引:0,他引:1
R. J. Macrae J. Henning S. B. Hill 《Journal of Agricultural and Environmental Ethics》1993,6(1):21-51
Strategies to involve agribusiness in the development of sustainable agricultural systems have been limited by the lack of a comprehensive conceptual framework for identifying the most critical supportive policies, programs and regulations. In this paper, we propose an efficiency/substitution/redesign framework to categorize strategies for modifying agribusiness practices. This framework is then used to identify a diverse range of short, medium, and long-term strategies to be pursued by governments, community groups, academics and agribusiness to support the transition. Strategies discussed include corporate greening, ethical investment, changing the legal status of the corporaton, new business forms and the development of ecological economics. 相似文献
253.
农业病虫害的灾变预测及预报精度分析 总被引:1,自引:0,他引:1
在农业病虫害突变规律的研究基础上,建立了定性与定量的尖角突变模型,确定了各病虫的突变区域。根据综合控制变量所确定的边界值,对未来病虫发生发展趋势进行预测。经多年历史资料检验和1992年农业病虫害发生突变的趋势预报证明:准确率高,覆盖面广。 相似文献
254.
华北地区主要农业灾害及灾情分析 总被引:3,自引:0,他引:3
本文分析了华北地区农业灾害发生的气象背景,并利用1981~1990年的农业统计资料分析了华北地区的农业灾情状况及因灾而造成的粮、棉损失量。华北地区单位耕地面积的受灾率及成灾率分别为47.3%和23.0%,大致相当于二年一遇灾和四年一成灾。华北地区因农业灾害而造成的粮、棉损失量平均每年为397.0和34.5万吨,粮、棉损失率分别为4.9%及15.3%。 相似文献
255.
Roger B. Long 《Journal of the American Water Resources Association》1980,16(6):1002-1005
ABSTRACT: At a time in history when water resource development in the United States is being condemned as both economically inefficient and an environmental disaster, perhaps economists need to look back at previous development to see what the fruits of water development (be they sweet or sour) have been. The Boise Project of south-western Idaho is 70 years old and to some people it represents a gross error in resource use, while to others it represents a means of livelihood and well being. A recent research project at the University of Idaho attempted to measure not only the direct economic income benefits of the project (from irrigation), but also the indirect or secondary income benefits (from the food processing industry). Periodic regional input-output tables were constructed to assess the income generated from irrigation and food processing over the period from 1946 to 1970. Input-output analysis allowed researchers to evaluate the direct and indirect impacts of both the irrigation sector and the food processing sector and to compare their growth over time. 相似文献
256.
H. I. Nightingale J. E. Ayars R. L. McCormick D. C. Cehrs 《Journal of the American Water Resources Association》1983,19(3):429-437
From 1971-1980, studies were conducted at Fresno, California, to identify and quantify, where possible, the soil and water chemistry, subsurface geologic, hydrologic, biologic, and operational factors that determine the long term (10-year) effectiveness of basin type artificial ground water recharge through alluvial soils. This paper updates previous findings and refers to publications that describe the geology beneath the basins and regional geology that determine the transmission and storage properties for local ground water management and chemical quality enhancement. High quality irrigation water from the Kings River was used for recharge. Construction and land costs for the present expanded facility 83 ha (205.2 ac) using three parcels of land were $1,457,100. The nine-year annual mean costs for only canal water, maintenance, and operation were $110.42/ha·m ($13.62/ac·ft) based on an average recharge rate of 1338 ha·m/yr (10,848 ac·ft/yr) at 86 percent facility efficiency. The measured end of season recharge rate averaged 14.97 ± 0.24 cm/day. The 10-year mean actual recharge rate based on actual water delivered, total ponded area, and total days of recharge was 12.1 cm/day. 相似文献
257.
Elwyn S. Krous Joseph P. Wagner Harold L. Parkinson Milton S. Sachs 《Journal of the American Water Resources Association》1971,7(4):810-822
ABSTRACT .A case study was performed to evaluate potential applications of desalted saline water for agriculture using 2 distillation type processes and 2 membrane type processes. The investigation determined the costs and benefits associated with desalting saline water at concentrations of 1,500, 900, 400, 200, and 50 ppm. Benefits from desalting are generated by shifts to more profitable crops, reduced costs for drainage, and reduction in fertilizer and labor requirements with better quality water. Costs are based on the project features such as desalting plants, raw water diversion facilities, storage reservoirs, conveyance and distribution systems, brine disposal, blending facilities, and gypsum addition systems. Hydrologic studies determined the crop irrigation requirements, water demand schedules, desalted water storage requirements, brine disposal requirements, and size of facilities required. Reconnaissance design layouts were made for producing desalted water using a combination of 14 schemes. The study also included a review of irrigation practices. The benefit-cost ratios range from 0.4 to 1.0 for 1,500 ppm irrigation water to 0.8 to 1.0 for 50 and 200 ppm water. Investment costs per acre are high, ranging from $12,900 to $20,900. Irrigation benefits are based on the increase in production from a desert condition with no water supply to the irrigation conditions studied. 相似文献
258.
新疆农业生态环境面临的问题与保护措施 总被引:1,自引:0,他引:1
新疆农业生态环境面临的主要问题有两大类:一类问题为生态问题;另一类问题为环境污染问题。简要介绍了新疆农业生态环境面临的生态问题,重点介绍了新疆农业生态环境面临的环境污染问题。针对新疆农业生态环境存在的问题,提出了相应的保护措施。 相似文献
259.
Michael R. Burkart William W. Simpkins Amy J. Morrow J. Michael Gannon 《Journal of the American Water Resources Association》2004,40(3):827-834
ABSTRACT: Seven sets of ground water samples from 103 observation wells were analyzed for total dissolved phosphorus (TDP) in four areas and five materials including loess and loess derived alluvium in the Deep Loess Hills of western Iowa, outwash and fractured till adjacent to Clear Lake in north central Iowa, fractured till in central Iowa, and a sand and gravel aquifer in northwest Iowa. Land use in ground water recharge zones in all four areas is dominated by crop or animal production or both. Concentrations of TDP exceeding the minimum laboratory detection limit of 20 μg/l as P were found in all areas and in all materials sampled. Samples from the outwash deposits associated with Clear Lake contained significantly larger concentrations than all other areas and materials with a median of 160 μg/l. Water from fractured till in three areas produced the smallest range of concentrations with a median of 40 μg/l. The mean value of TDP in all sample sets exceeded 50 μg/l, an important ecological threshold that causes increased productivity in lakes and perennial streams and one being considered as a surface water nutrient standard by regulatory agencies. These results clearly show that ground water in essentially all near‐surface aquifers and aquitards discharging to Iowa's streams and lakes is capable of sustaining P concentrations of 50 to 100 μg/l in streams, lakes, and reservoirs. Consequently, even if point discharges and sediment sources of P are substantially reduced, ground‐water discharge to surface water may exceed critical thresholds under most conditions. 相似文献
260.
Innovative approaches to rural development: Moving from state-controlled towards market-based land reform 总被引:1,自引:0,他引:1
Frederico Neto 《Natural resources forum》2004,28(1):50-60
Among the world's poor, approximately 75% of those in extreme poverty live and work in rural areas and two‐thirds of them depend mainly on farming or farm labour for their livelihood. Policies to grant the rural poor secure access to land and water for irrigation — and to improve the economic efficiency of small‐scale agriculture — can thus play a critical role in the implementation of rural development strategies, including efforts to combat rural poverty. Since inadequate access to arable land is probably the most important cause of rural poverty, redistributive land reform is increasingly seen as crucial for socio‐economic development and poverty alleviation in many developing countries with substantial amounts of (unused) arable state land or (under‐utilized) large private landholdings. This article argues that market‐based land redistribution schemes, such as the one being implemented in South Africa, can be considered one of the most innovative approaches to land reform that have emerged over the last decade. These schemes thus provide a useful alternative to more conventional, state‐controlled land redistribution programmes. The article concludes, however, that when countries opt for market‐based approaches to land redistribution, the State still has an important role to play, without necessarily deciding which land parcels change hands. 相似文献