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751.
山东省珍稀濒危植物的区域分布及其保护 总被引:1,自引:0,他引:1
本文分析了山东省珍稀濒危植物的种类、区域分布及其产生的原因,提出了保护和合理开发利用的对策。 相似文献
752.
M. Anne Naeth David S. Chanasyk 《Journal of the American Water Resources Association》1996,32(1):89-95
ABSTRACT: Grazing can have a profound impact on infiltration and thus runoff and erosion. The objectives of this study were to quantify the effects of select grazing systems on rainfall and snowmelt induced runoff and sediment yield from sloped areas of the foothills fescue grasslands of Alberta, Canada. The effects of two grazing intensities (heavy and very heavy) for two durations (short duration and continuous throughout the growing season) were compared to an ungrazed control between June 1988 and April 1991. Runoff was measured using 1-rn2 runoff frames and collection bucket systems. Sediment yields were then determined on samples from the collected runoff. Snowmelt was the dominant source of runoff. Snowmelt runoff was higher from the heavily grazed areas than from the very heavily grazed areas, due to the higher standing vegetation which accumulated snow in the former areas. Sediment yields as a result of snowmelt were generally low in all areas. Only a few summer storms caused runoff. Runoff volumes and sediment yields from summer rainstorms were low, due to low rainfall and to generally dry antecedent soil moisture conditions. The greatest risk of summer runoff, and thus sediment yield, appears to occur in August. 相似文献
753.
James C. Adamski Aaron L. Pugh 《Journal of the American Water Resources Association》1996,32(1):97-105
ABSTRACT: Pesticides were detected in ground-water samples collected from 20 springs and nine wells in the Ozark Plateaus Province of Arkansas, Kansas, Missouri, and Oklahoma. From April through September 1993, water samples were collected from 50 shallow domestic wells and 50 springs in the Springfield Plateau and Ozark aquifers and analyzed for 47 pesticides and metabolites. Pesticides were detected in 17 water samples from the Springfield Plateau aquifer and 12 water samples from the Ozark aquifer. Fourteen pesticides were detected, with a maximum of four pesticides detected in any one sample. The most commonly detected pesticides were atrazine (14 detections), prometon (11 detections), and tebuthiuron (seven detections). P, P' DDE, a metabolite of DDT, was detected in water samples from three wells and one spring. The remaining pesticides were detected in three or less samples. The occurrence and distribution of pesticides probably are related to the local land use near a sampling site. Pesticide detections were significantly related to aquifer, site type, and discharge of springs. 相似文献
754.
Seema Bathla 《Environment, Development and Sustainability》1999,1(2):105-121
The paper examines the linkages between water depletion, continuous population growth and economic development viewed primarily as agricultural development. This is done within a framework of a dynamic simulation model of ecological-economic type over extended periods of time. It is found that intensive agriculture, driven by an increase in the cropping intensity as a result of increase in area under paddy crop, has led to an increased gap between the demand for and supply of water resources, in particular subsurface resources. The consequent fall in water table may lead to constraints in the use of water. This has strong inequity implications in the resource use as well as threats to future of agricultural development in the region. It is revealed that a mix of interventions based on price solutions, non-price solutions and institutional set up are decisive in bringing a sustainable development and use of resource. The paper concludes with emphasising the role of state/government in achieving the desired goal. 相似文献
755.
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
756.
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
757.
Glen C. Filson 《Journal of Agricultural and Environmental Ethics》1993,6(2):165-184
This paper provides an analysis of a 1991 survey of the views of a stratified random sample of 1,105 Ontario farmers. Factor analysis, Kruskal—Wallis one-way ANOVA, chi-square and correlations were used to identify differences in farmers' attitudes toward rural environmental issues as a function of their demographic and farm characteristics. Younger, well-educated farmers, especially if female, were most concerned about the seriousness of rural environmental degradation. The largest operators expressed the greatest support for the use of agricultural chemicals, were most opposed to government conservation regulations and were least environmentally oriented. Such differences between Australian and Ontario farmers as the former's greater cautiousness about governmental regulation and receptivity to the Green Movement are a function of differing demographic and farm characteristics between Australia and Ontario. 相似文献
758.
贵州南部河谷热带性植物共计464种、2变种。主要构成3种植被类型:大型羽状复叶林、稀树草坡灌丛与肉质多刺灌丛。可分为11类经济用途:药用(139种)、纤维(38种)、野果(21种)、观赏(21种)、鞣料(18种)、饲料(13种)、油脂(13种)、淀粉(12种)、紫胶虫寄主(11种)、芳香(6种)、染料(5种)。资源流失与环境变化,使现存资源的保护与深层次利用成为当前的主要问题。 相似文献
759.
J. K. Mitchell B. A. Engel R. Srinivasan S. S. Y. Wang 《Journal of the American Water Resources Association》1993,29(5):833-842
ABSTRACT: The AGNPS (AGricultural NonPoint Source) model was evaluated for predicting runoff and sediment delivery from small watersheds of mild topography. Fifty sediment yield events were monitored from two watersheds and five nested subwater-sheds in East Central Illinois throughout the growing season of four years. Half of these events were used to calibrate parameters in the AGNPS model. Average calibrated parameters were used as input for the remaining events to obtain runoff and sediment yield data. These data were used to evaluate the suitability of the AGNPS model for predicting runoff and sediment yield from small, mild-sloped watersheds. An integrated AGNPS/GIS system was used to efficiently create the large number of data input changes necessary to this study. This system is one where the AGNPS model was integrated with the GRASS (Geographic Resources Analysis Support System) GIS (Geographical Information System) to develop a decision support tool to assist with management of runoff and erosion from agricultural watersheds. The integrated system assists with the development of input GIS layers to AGNPS, running the model, and interpretation of the results. 相似文献
760.
Laszlo David Lucien Duckstein 《Journal of the American Water Resources Association》1976,12(4):731-754
ABSTRACT The definition and comparison of alternative water resource systems designed to meet long-range goals (say 60 years) is illustrated by a case study in Hungary. A comprehensive cost-effectiveness approach is adapted to define goals, specifications, criteria, alternatives and their capabilities. Specifications include demands given in probabilistic terms. The comparison of alternative systems is based on 12 criteria, one of which is the balance between total energy consumed and peak energy produced. Important factors involving social elements, such as flood protection and land and forest use, are described both as monetary quantities and as qualitative appreciations. Five alternative systems are defied involving flat land reservoirs, pumped storage reservoirs, interbasin transfer, and conjunctive use of surface and ground water. International cooperation is then used to rank systems and reduce the problem to a tradeoff between only two alternatives. 相似文献