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401.
天津市农田土壤污染现状与防治对策 总被引:5,自引:0,他引:5
分析了天津市农田重金属污染和农药残留污染状况 ,提出了防治重金属污染的物理、生物、农艺防治措施 ,以及防治农药污染的微生物措施等。 相似文献
402.
综述了现代常规农业对土壤的污染、有机农业的特点及有机农业土壤保护措施的生态学原理。 相似文献
403.
NASA’s Earth Observation System (EOS) satellite data are contributing to the development of policy relevant, remote sensing applications. To promote the use of EOS data for application development, NASA funded the Synergy program in 2000 in partnership with academia, end users, and industry. Three examples of remote sensing applications from the Synergy program are presented here and include agriculture, range management, and water resource management. These examples show that remote sensing products have the potential to be useful to a variety of decision makers and policy makers because of the opportunity to reduce chemicals in the environment, improve crop yields and better manage range lands and water resources. Transitioning from research and development to successful applications must overcome challenges such as the lack of awareness by end users of these technologies, inadequate feedback mechanism between application developers and end users, and unproven cost benefits of remote sensing data. Experience from the Synergy program indicates that these issues could be mitigated by educating and training end users, demonstrating the utility of remote sensing data in improving decision making, and establishing and maintaining a continuous dialogue between developers and end users. Sustainability of remote sensing applications ultimately depends on users continuing reliance on products and benefits from remote sensing data. The Synergy program also demonstrates that remote sensing data sets that are collected primarily for global change research contribute to the development of applications in a variety of disciplines at the regional and local level. 相似文献
404.
Mizina Svetlana V. Smith Joel B. Gossen Erwin Spiecker Karl F. Witkowski Stephen L. 《Mitigation and Adaptation Strategies for Global Change》1999,4(1):25-41
Agriculture in Kazakhstan is sensitive to climate, and wheat yields could be reduced up to 70% under climate change. With the transition from a socialist economy to a free market economy, decisions are being made now that will affect Kazakhstan's ability to cope with climate change. A team of Kazakh and American researchers examined the cost-effectiveness and barriers to implementations of adaptation options for climate change. Twelve adaptation options that increase flexibility to respond to climate change were identified using a screening matrix. Four options, forecasting pest outbreaks, developing regional centers for preserving genetic diversity of seeds, supporting a transition to a free market, and reducing soil erosion through the use of changed farming practices, were examined. The Adaptation Decision Matrix (ADM) was then applied to estimate benefits using expert judgment (using an arbitrary numerical scale, not monetary values) and benefits estimates were compared to costs to determine cost-effectiveness. The ADM uses subjective measures of how well adaptation options meet policy objectives. Controlling soil erosion was estimated to have the highest benefits, but the high costs of implementation appears to make it relatively cost-ineffective. Supporting a transition to a free market was ranked as the most cost-effective measure, with regional centers second. However, use of different scales to quantify benefits or different weights can result in regional centers being more cost-effective than the transition to a free market. Regional centers was also judged to have fewer barriers to implementation than a transition to a free market. These results will be incorporated in Kazakhstan's National Action Plan. The ADM and other tools are relatively easy to apply, but are quite subjective and difficult to evaluate. The tools can be quite useful by decision makers to analyze advantages and disadvantages between different adaptation options, but should be supplemented with additional, particularly quantitative analysis. 相似文献
405.
This study evaluates the theoretical impact of climate change on yields and water use of two crops with different responses
to increased CO2 and which represent contrasting agricultural systems in Spain. In all cases the simulated effects of a CO2-induced climate change depended on the counteracting effects between higher daily ET rates, shortening of crop growth duration
and changes in precipitation patterns as well as the simulated effects of CO2 on the water use efficiency of the crops. For summer irrigated crops such as maize, the yield reductions and the exacerbated
problems of irrigation water availability simulated with climate change may force the crop out of production in some regions.
For winter dryland crops such as wheat, productivity increased significantly in some regions, suggesting a northward shift
of area suitable for wheat production in future climates. The study considered strategies for improving the efficiency of
water use based on the optimization of crop management decisions in a CO2-driven warmer climate.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
406.
本文通过对内蒙古化德县七号乡小公勿素村几个生态模式系统结构、产业结构、系统功能及畜草平衡的分析,提出在内蒙古阴山北麓农牧交错带进行生态经济型农业建设的途径和农业可持续发展的系统结构与模式。 相似文献
407.
中国农业用水的评价、存在问题及解决途径 总被引:7,自引:2,他引:7
本文根据大量数据论述了中国农业用水对全国农业发展的重要意义、中国农业用水现状及其面临的主要问题,并提出了解决途径关键词 相似文献
408.
城乡交界处是现代农业的重要组成部分。它可以解决城市人口的食物供应问题,增加就业机会,改善城市生态。但是城乡交界处同时也会带来一些新老环境问题,如果没有正确管理和合理的规划,它也会给城市环境造成危害,进而影响人类的健康。本文结合都市农业对环境和人类健康存在的潜在危害做了具体的分析,并提出一些切实可行的管理和控制措施。 相似文献
409.
随着城乡人民生活水平的提高,人们对农产品 的质量提出了更高的要求。立足苏州农业生产现状,提 出建设生态农业的必要性和紧迫性。通过对现实存在 问题的分析,提出苏州地区生态农业的发展思路及有关措施。 相似文献
410.