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101.
黑龙江甘南县大气降尘重金属元素沉降通量及来源分析   总被引:2,自引:0,他引:2  
从2009年3月到2010年3月,采用被动式同时采集了黑龙江甘南县17个点的大气降尘样品,分析了Cd、Hg、Cr、Mn、Ni、Pb、As、Cu、Zn九种元素的含量,对重金属元素沉降通量进行了计算和分析,并利用富集因子分析和相关性分析的方法对元素来源做了解析。研究表明:降尘中重金属元素Mn的年沉降通量数据值较高,均值为7...  相似文献   
102.
三台县是一个农业大县,随着农业经济的迅速发展,农业面源污染日趋严重。种植业污染、畜禽养殖、农村生活污染成为三台县农业面源污染的主要因素。面源污染具有分散性、随机性和监测成本高的特点。对三台县农业面源污染产生进行了经济学分析,农业面源污染属于外部不经济性,通过建立生态补偿机制,控制农业面源污染。以三台县建立生态县和新农村建设为基础,通过转变农业生产方式,调整产业结构,发展生态农业,推进生态村的建设等生态补偿治理措施,改善三台县的农业生态环境。  相似文献   
103.
Abstract

The natural supply of land resources is limited, but the economic supply may change along with social and economic development, and its size is decided bye nature and social and economic body conditions. When the supplying ability of land resources threatens the development of society and the conflict between people and land becomes tense, it forced people to improve land utilization and to increase the effective supply of land resources. The paper made an overall consideration on the characteristics of the irrigated farming and the frail ecological environment in Fuhai County, Altay Area, Xinjiang Uigur Autonomous Region and explored land arrangement planning as well as water resource planning and environmental protection. The paper evaluated natural resources, land utilization and water resource of the case study areas and focused on the spatio-temporal balance between the utilization of water and land resources. In the end the paper a feasible plan was made out for the land arrangement project.  相似文献   
104.
Using rural survey data for the year 2009,we provide evidence of work choices of rural laborers in ecologically vulnerable areas in North China,and model these choices as a function of characteristics of individuals,households,and land endowments.The findings reveal large differences between males and females,and between non-farm employment and part-time farming engagement Land scarcity is still an important driving factor in non-farming participation of rural laborers in the study area;and in the current case of land productivity and the total amount of land,there are still surplus rural labor forces in the study area.Diversification of livelihood reduces the pressure on land,thus facilitating ecosystem conservation.So,the paper concludes with the argument that establishing coordination mechanisms among non-farm employment of rural laborers,agricultural production,and restoration of ecosystems are essential for mitigating the conflicts of ecological security,agricultural production,and rural development in mis area.  相似文献   
105.
Abstract

Miyun County, located in the northeast of Chinese capital Beijing, was underwent remarkable variations in land use in recent years. This paper aimed to detect changes in land use of Miyun from 1997 to 2005, and to qualify the response of ecosystem to LUCC based on ecosystem services valuation. With two-periods TM images, we got land use change data, and then ecosystem services values were calculated using ecosystem services valuation coefficients proposed by Chinese scholar Xie Gaodi. Results showed that water area, farm land and unused land decreased while residential land, forest land, grassland and orchard land increased during the study period. The loss of ESV was RMB 206 million and the main reason was the decrease of water area and farm land area. As for spatial variation, there were most dramatically land use change and ESV decline in reservoir ecological protection region. The coefficient sensitivity analysis indicates that valuation coefficients used in the study are suitable and results are reasonable. The driving forces of ESV loss were rapid population growth and economic development. More work should be done to make eco-environment stay healthy.  相似文献   
106.
氟和碘作为人体必需的微量元素,过少或过多摄入都会影响人身健康,相较于缺氟、缺碘,高氟高碘地下水对人体的危害更加难以控制。该研究选择单县作为典型的水源型高氟高碘地区,通过对浅层高氟高碘地下水进行采样测试,采用箱线图、Piper图及双变量相关性分析等多元统计技术剖析了该区域浅层地下水的水环境特征;采用R型因子分析揭示了水化学成分之间的相互关系,探讨了该区浅层高氟高碘地下水的成因。结果表明:①单县浅层地下水中的氟化物和碘化物的质量浓度均值分别为1.2 mg/L和391 μg/L。②随着氟化物浓度的增加,水化学类型偏向于向HCO3-Na型和HCO3-Na·Mg型集中,而随着碘化物浓度的增加,水化学类型则倾向于以HCO3-Na·Mg为主。③该区域强烈的蒸发浓缩作用是控制单县浅层地下水化学成分的最重要因子;萤石平衡控制作用是控制单县浅层地下水高氟背景的因子;水-有机沉积物相互作用是控制单县浅层地下水高碘背景的因子。  相似文献   
107.
为了调查新疆于田县的水质和水资源特色,2010 年和2012 年在新疆于田县及于田县邻区采集水样,并对其元素含量进行分析测定。结果在新疆于田县新发现一个优质天然富锂富锶饮用矿泉水水源,水化学类型为Na·Mg-HCO3·Cl,锂含量1 765.5 μg/L,锶含量1.1 mg/L,分别为国家饮用矿泉水锂(Li≥200 μg/L)和锶(Sr≥0.2 mg/L)最低界限指标的8.8 倍和5.5 倍。于田县城饮用矿泉水含水层厚度大,岩性为卵砾石,透水性好,水量较丰富。于田县优质矿泉水与国内外主要矿泉水相比,具有富锂、富锶等有益元素,且富锂矿泉水是中国稀缺的矿泉水资源,因此具有广阔的市场前景。  相似文献   
108.
区域生态环境变化的遥感评价指数   总被引:29,自引:0,他引:29       下载免费PDF全文
基于遥感信息技术提出一个新型的遥感生态指数(RSEI),以快速监测与评价区域生态质量.该指数耦合了植被指数、湿度分量、地表温度和土壤指数等4个评价指标,分别代表了绿度、湿度、热度和干度等4大生态要素.与常用的多指标加权集成法不同的是,本研究提出用主成分变换来集成各个指标,各指标对RSEI的影响是根据其数据本身的性质来决定,而不是由人为的加权来决定.因此,指标的集成更为客观合理.将RSEI应用于福建长汀水土流失区,并与国家环境保护部《生态环境状况评价技术规范》中的生态指数EI的计算结果相比较,发现二者的结果具有可比性.不同的是,RSEI不仅可以作为一个量化指标,而且还可以对区域生态环境变化进行可视化、时空分析、建模和预测.因此,可弥补EI指数在这些方面的不足.  相似文献   
109.
云南省玉龙县碳减排效应估算   总被引:1,自引:0,他引:1       下载免费PDF全文
郭飞  香宝  马广文  李双权 《环境科学研究》2009,22(11):1317-1322
玉龙县碳减排效应估算主要包括退耕还林、造林、小水电、替代能源(包括沼气池和太阳能)使用等方面. 其中,造林具有较长期的碳汇功能,会持续提供碳增汇服务功能;替代能源的使用可以有效减少薪柴燃烧,在以农村人口为主的玉龙县,薪柴是主要的取暖和生活能源,故替代能源的使用颇具意义. 以2005年为基准年,小水电和替代能源总的碳减排效应为22.24×103 t,其中小水电碳减排效应为14.43 ×103 t,太阳能碳减排效应为66.24 t,沼气池碳减排效应为7.74×103 t;设定了基准年后林木生长过程以及替代能源使用状况的情景,并进行情景模拟,估算了玉龙县造林在5年内会产生碳汇21.07×103 t,10年内会产生碳汇24.92×103 t. 在研究区总的碳减排效应中,小水电、沼气池以及生态林地都有较大贡献,而经济林和草地的贡献相对较小;与5年情景相比,20年情景中小水电和沼气池的贡献有所上升,而生态林地等的贡献相对下降.   相似文献   
110.
To study heavy metal pollution and assess the health risk of river water in Huayuan County, Xiangxi, Hunan Province, 11 water samples were collected from the Huayuan River and Brother Rivers in August and December 2016. Heavy metal (Pb, Zn, Cr, Cu, Fe, and Ni) concentrations were determined from the samples. The health risk assessment model recommended by the U.S. Environmental Protection Agency (USEPA) was applied to assess the health risk of heavy metals in the main surface waters of Huayuan County. The results indicated that the concentrations of heavy metals (Pb, Zn, Cr, Cu, Fe, and Ni) of surface water in the research area were 2.57 × 10-3, 4.66 × 10-4, 1.65 × 10-3, 6.27 × 10-4, 0.19, and 8.50 × 10-4 mg/L, respectively. The health risk of surface waters with heavy metals was high. Therefore, the chemical carcinogenic substance (Cr) health risk index was five or six times higher than that of chemical non-carcinogens (Pb, Zn, Cu, and Ni). The average health risk indices of non-carcinogenic substances were in the order Pb > Cu > Zn > Ni. The correlation and principal component analysis of surface water showed that the six heavy metal elements were composed of three main components in the main surface waters of the county. The first principal component was comprised of Fe and Ni (33.28%), which was mainly from internal pollution. The second component was comprised of Cu and Cr (26.98%), which was primarily due to industrial waste water, rainwater leaching mineral waste produced by heavy metal mining, and smelting enterprises. The third component, resulting from geochemical pollution, was Zn (17.10%). The health risk indices triggered by heavy metal in surface waters was high. Heavy metal pollutants in the research area need to be controlled in the order Cr, Pb, Cu, Zn and Ni. © 2018 Science Press. All rights reserved.  相似文献   
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