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451.
Evaluation of the economic and environmental impact of converting cropland to forest: a case study in Dunhua county, China 总被引:2,自引:0,他引:2
Wang C Ouyang H Maclaren V Yin Y Shao B Boland A Tian Y 《Journal of environmental management》2007,85(3):746-756
The Sloping Land Conversion Program (also known as "Grain for Green" or the Upland Conversion Program) for converting cropland to forest is one of China's most ambitious environmental initiatives, and is one of the world's largest land-conservation programs with a budget of RMB 337 billion (over US$ 40 billion). Although environmental impacts have played a vital role in the general reasoning and argumentation for forest plantations, environmental impact analyses have often received less attention than economic analyses in the planning of plantation forestry projects. The overall goal of this paper is to evaluate the program's environmental impact considering the farmer's interests and the potential social benefits due to carbon sequestration in different scenarios based on household and field survey data in Dunhua County. Our findings are that: (1) in many cases, the program did not give adequate consideration to land productivity and environmental heterogeneity when selecting plots; (2) more than half of the reforestation plots were on flat cropland (slopes of less than 5 degrees ); (3) in five of the eight townships, net incomes on reforested land were substantially above or below previous crop incomes, raising questions about the efficiency of the allocation of compensation to farmers participating in the program; (4) the potential carbon co-benefit increased the NPV of the program by 5954-7009 RMB/ha. In conclusion, we recommend that more attention should be paid to the quality of reforestation programs rather than just their scale and note that consideration of potential carbon sequestration co-benefits enhances the benefits of cropland conversion programs. 相似文献
452.
油田含油污水生化处理技术研究及应用 总被引:1,自引:0,他引:1
国内油田在原油生产过程中的产出污水,大部分经过处理后作为水驱采油的水源,部分多余的水经过适当处理后排放,对油田周边环境造成污染.1998年国务院颁布了<关于环境保护若干问题的决定>,决定要求,2000年以前,全国所有工业污染源必须达到国家或地方规定的排放标准. 相似文献
453.
Monitoring seasonal distribution of an endangered anadromous sturgeon in a large river using environmental DNA 总被引:1,自引:0,他引:1
Nian Xu Bin Zhu Fang Shi Ke Shao Yanfu Que Weitao Li Wei Li Wenjing Jiao Hua Tian Dongmei Xu Jianbo Chang 《Die Naturwissenschaften》2018,105(11-12):62
Monitoring dynamic distribution is crucial to conservation management of anadromous sturgeons, but traditional survey methods are less efficient for low-density populations in a large river. Natural propagation of Chinese sturgeon has been monitored annually mainly at the spawning ground using netting for eggs and hydroacoustics for broodstock. However, absence of spawning was observed sporadically in recent years, indicating further crises for the declining population. We analyzed eDNA of water samples collected from 24 sites across 1360 km of the migratory route of anadromous Chinese sturgeon in the middle and lower reaches of the Yangtze River. Chinese sturgeon was detected at 9 sites during the spawning season and 14 sites after the spawning season. We found that positive eDNA detection rates remained constant in the middle reaches but dramatically changed in the lower reaches, reflecting seasonal migration pattern of Chinese sturgeon. Invasive sturgeons were detected in the river, indicating their possible escape from aquaculture facilities. This study established a protocol for the use of eDNA to monitor distribution of Chinese sturgeon and could be valuable in making better policies for the conservation of this endangered species. 相似文献
454.
Health institutions in the People's Republic of China are under considerable challenge. Innovations in management systems may support the challenge to increase both efficiency and effectiveness. The balanced scorecard (BSC) is one such innovation. We have used a model to explore the factors that may impact the diffusion of the BSC in Chinese government hospitals. In particular, we concentrate on three factors - the outer context, the nature of the innovation and the communication and influence. The outer context and the nature of the innovation do provide an inducement to implement a BSC. The strength of the communication and influence may affect the level of take-up. However, we recognise that they may choose "the BSC not for any apparent technical excellence but for the legitimation that Western management practices may bring to local managers. 相似文献
455.
遥感旱灾模型综合分析 总被引:8,自引:0,他引:8
本文在野外实验的基础上,对遥感旱灾模型进行综合分析和评价。运用四年的实地观测数据,校正了旱灾模型中的待定系数,使其能用于NOAA气象卫星对旱情的监测。对复杂的蒸散模型简化的可行性进行了尝试性研究。 相似文献
456.
457.
In this paper, downward movement of phosphorus and copper as dredged sediment applied on sandy loam soil was studied by column leaching experiments. Three sediment application rate, (i.e., 1, 2 and 5-cm depth of sediments) were applied to the top of the soil columns. Two and a half months leaching experiments were conducted, which include a 15-day un-watered period. Concentrations of phosphorus and copper in the leachate and the vertical distribution of Olsen-P and diethylenetriaminepentaacetic acid (DTPA) extractable Cu in the soil columns were determined. The results showed that, un-watered period could increase the downward movements of phosphorus and copper. Sediment application significantly increased Olsen-P concentration in the top 15 cm of the soil columns, but has not significantly affected that in the deeper soil layer. The 1-cm depth sediment treatment did not increase the DTPA extractable Cu concentration in the whole soil column. The 5-cm depth sediment treatment, however, significant increased the DTPA extractable Cu in the deeper soil layers. This study suggested that the application of dredged sediment laden with P and Cu on sandy loam soil might cause the significant downward movement of phosphorus and copper. 相似文献
458.
近年来,我国沿海地区越来越频繁的赤潮对水域环境与海水养殖业等造成了严重破坏。本文从赤潮发生的条件入手,分析了赤潮的预测方法,并提出了相应的对策。 相似文献
459.
460.
人类工效型背具的研究 总被引:1,自引:0,他引:1
从人类工效学和劳动生理学角度,对背具的肩带宽度、内背架设置等进行了实验研究和实用效果评价。对背具的设计原则和生物力学配置提出了建议和改进方法 相似文献