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911.
青海湖流域生态补偿空间选择与补偿标准研究 总被引:2,自引:1,他引:2
生态补偿是环境保护对策措施中的一种创新途径.以青海湖流域为研究区域, 以碳蓄积量作为主要生态系统服务目标, 结合人文调查数据和自然模拟结果, 分别采用福利成本法和最小数据方法对研究区生态补偿中的空间选择和补偿标准确定进行了分析.结果表明: 环青海湖四个县的生态补偿效率成本比分别是海晏县0.5353、 刚察县0.5398、 天峻县0.5549、 共和县0.4353.在生态补偿资金有限的情况下, 生态补偿的优先顺序依次是天峻、 刚察、 海晏, 最后是共和.若海晏县全部低盖度草地退牧则需付费328.5元·hm-2·a-1, 可年新增碳固定量1.7×107 kg; 若刚察县全部低盖度草地退牧则需付费250.5元·hm-2·a-1, 可年新增碳固定量5.25×107kg; 若天峻县全部低盖度草地退牧则需付费181.5元·hm-2·a-1, 可年新增碳固定量18.52×107kg; 若共和县全部低盖度草地退牧则需付费478.5元·hm-2·a-1, 可年新增碳固定量2.86×107kg. 相似文献
912.
利用 PcRaster 的环境动态模拟语言,基于地图运算和网格之间水流运动的模拟,开发了水文过程模拟模型,选择 太湖流域上游的西苕溪流域进行试验,用实测资料对模拟结果进行了验证,结果表明模型模拟结果与实际是符合的.本 模型可以用于流域的物质迁移、污染物迁移、人类活动的环境影响变化等的模拟.在此水文过程模拟的基础上,只要叠加 网格上的物质产出率,就可以很容易得到子流域出口的物质通量的变化和其在流域上的空间分布,集成各个子流域过程, 就可以得到流域出口断面的物质通量的变化. 相似文献
913.
Prior to hydrologic modelling, topographic features of a surface are derived, and the surface is divided into sub‐basins. Surface delineation can be described as a procedure, which leads to the quantitative rendition of surface topography. Different approaches have been developed for surface delineation, but most of them may not be applicable to depression‐dominated surfaces. The main objective of this study is to introduce a new depression‐dominated delineation (D‐cubed) method and highlight its unique features by applying it to different topographic surfaces. The D‐cubed method accounts for the hierarchical relationships of depressions and channels by introducing the concept of channel‐based unit (CBU) and its connection with the concept of puddle‐based unit (PBU). This new delineation method implements a set of new algorithms to determine flow directions and accumulations for puddle‐related flats. The D‐cubed method creates a unique cascaded channel‐puddle drainage system based on the channel segmentation algorithm. To demonstrate the capabilities of the D‐cubed method, a small laboratory‐scale surface and 2 natural surfaces in North Dakota were delineated. The results indicated that the new method delineated different surfaces with and without the presence of depressional areas. Stepwise changes in depression storage and ponding area were observed for the 3 selected surfaces. These stepwise changes highlighted the dynamic filling, spilling, and merging processes of depressions, which need to be considered in hydrologic modelling for depression‐dominated areas. Comparisons between the D‐cubed method and other methods emphasized the potential consequences of use of artificial channels through the flats created by the depression‐filling process in the traditional approaches. In contrast, in the D‐cubed method, sub‐basins were further divided into a number of smaller CBUs and PBUs, creating a channel‐puddle drainage network. The testing of the D‐cubed method also demonstrated its applicability to a wide range of digital elevation model resolutions. Consideration of CBUs, PBUs, and their connection provides the opportunity to incorporate the D‐cubed method into different hydrologic models and improve their simulation of topography‐controlled runoff processes, especially for depression‐dominated areas. 相似文献
914.
测试流经稀土矿区河水的p H和Eh值,可以反映矿区的酸碱性、氧化还原环境。本文以赣南地区濂水、桃江、东江流域为研究对象,利用ICP-MS和三通道多参数测试仪分别测试水样中溶解态稀土含量(DREEs)和p H、Eh值,分析p H、Eh值的变化特征以及DREEs含量与p H值的相关性。结果表明:1研究区水体中DREEs含量变化较大,介于几μg/L至几十mg/L之间;DREEs经球粒陨石标准化后表现为弱的轻稀土富集模式,Eu、Ce显示负异常;2溶解态稀土及La含量分别与p H值呈弱的负相关性,说明地表水体中DREEs浓度及分布模式在一定程度上受外部环境酸碱性的影响;3对于流经地层、地层内离子吸附型稀土矿区的水样,其p H均值分别为7.40、6.94,Eh均值分别为-0.023 V、6.55 mV;对于流经岩体、风化壳离子吸附型稀土矿区的水样,其p H均值分别为6.61、4.37,Eh均值分别为0.024 V、0.15 V,表明赣南地区离子吸附型稀土矿区处于中酸性的氧化环境。 相似文献
915.
916.
ForoodAZARIDEHKORDI MajidFMAKHDOUM NobukazuNAKAGOSHI 《中国地理科学(英文版)》2003,13(4):328-333
The major concern of this article is to address the shortcoming and outgoing effects of the human activities on the landscape patterns and their consequences in the Sefidrood River watershed in Iran. A flow of data includes three inputs; each of them belongs to one part of three zones of a fluvial system. The three parts of the Sefidrood River fluvial system include Zone 1, a sub-watershed as degradation modeling site, Zone 2, Sefidrood Dam asdam site, and Zone 3, 17kin away from the Sefidrood River path to the Caspian Sea as ending point site. The degra-dation model in the Zone 1 provides a suitable mean for decision support system to decrease the human impacts oneach small district. The maximum number for degradation coefficient belongs to the small district with the highest physiographic density, relatively cumulative activities, and a lower figure for the habitat vulnerability. The human degradation impact were not limited to the upstream. The investigation to the Sefidrood Dam and ending point of the Sefidrood River depicts that sedimentation continues as a significant visual impact in the Sefidrood Dam reservoir and the estuary. 相似文献
917.
918.
基于DEM的福建省小流域划分研究 总被引:5,自引:0,他引:5
以1∶10万的数字线划图为工作底图,在ARC/INFO软件环境下,采用空间内插法生成福建省的DEM。其在ARC/INFO软件的水文模块环境下,经过数据预处理、流向分析、汇流分析和流域识别等过程,最终自动提取1435个小流域。研究结果表明:在山区,流域界线基本与分水岭吻合,但在平坦地区由于等高线稀疏,加上福建海岸线非常曲折,海湾支离破碎,流域提取的结果不尽人意,流域界线需要人工进一步修正。基于DEM的流域的快速提取,大大节省了的人力、物力,从提取的效率和精度来看都是切实可行的。随着DEM的精度将不断提高,这种方法将为在全省范围内实现流域各自然要素空间组合特征的快速分析与站点观测数据的综合管理,以及流域信息的空间可视化浏览、查询、统计和流域水文模型的应用分析奠定了坚实的基础,从而推动了生态环境保护、生态环境建设等生态环境管理工作的实施。 相似文献
919.
ABSTRACTWhen applying a distributed hydrological model in urban watersheds, grid-based land-use classification data with 10 m resolution are typically used in Japan. For urban hydrological models, the estimation of the impervious area ratio (IAR) of each land-use classification is a crucial factor for accurate runoff analysis. In order to assess the IAR accurately, we created a set of vector-based “urban landscape GIS delineation” data for a typical urban watershed in Tokyo. By superimposing the vector-based delineation map on the grid-based map, the IAR of each grid-based land-use classification was estimated, after calculating the IARs of all grid cells in the entire urban watershed. As a result, we were able to calculate the frequency distribution of IAR for each land-use classification, as well as the spatial distribution of IARs for the urban watershed. It is evident from the results that the reference values of IAR for the land-use classifications were estimated very roughly and inherited errors of between about 7% and 70%, which corresponds to more than 100 mm increase of direct runoff for the 1500 mm annual average precipitation.
Editor D. Koutsoyiannis; Guest editor E. Volpi 相似文献
920.