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201.
Soil sediment samples of 10 layers with a spacing of 10 cm each were collected in different floodplain zones adjacent to Huolin
River in the Xianghai Nature Reserve, and contents of total N, total P and organic matters were analyzed. The results showed
that contents of total N, total P and organic matters were generally decreasing with the increase of distance from sample
locations to the river channel, and contents of the three items were generally higher in the upper soil layer than that in
the lower soil layer. The content variations displayed how flooding functions influenced nutrient matter content variations
in floodplain soils since the flood inundation frequencies of the sample locations varied. The correlation analysis displayed
that there were remarkable relativities between total N, total P and organic matters within definite spatial distance from
the Huolin River channel. 相似文献
202.
Through the study of mutual process between groundwater systems and eco-environmental water demand, the eco-environmental
water demand is brought into groundwater systems model as the important water consumption item and unification of groundwater’s
economic, environmental and ecological functions were taken into account. Based on eco-environmental water demand at Da’an
in Jilin province, a three-dimensional simulation and optimized management model of groundwater systems was established. All
water balance components of groundwater systems in 1998 and 1999 were simulated with this model and the best optimal exploitation
scheme of groundwater systems in 2000 was determined, so that groundwater resource was efficiently utilized and good economic,
ecologic and social benefits were obtained. 相似文献
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略论目标规划及交互方法在小康示范村规划中的实践--以西藏贡嘎县沃拉村为例 总被引:1,自引:0,他引:1
建设全面小康社会是我国本世纪头20年的核心内容,目前已经有越来越多的人加入到这一研究领域中,该领域的规划研究工作正在逐渐加强。本文以西藏贡嘎县沃拉村为例,介绍了目标规划及交互方法小康示范村规划中的实践,讨论了规划的过程、建模方法及模型的精度等问题,认为在研究人员的指导下,由村民学习并建模的方法是今后小康村规划的发展方向。 相似文献
206.
中外饭店区域集团化特征对比研究 总被引:7,自引:0,他引:7
随着饭店业全球化进程的发展,饭店之间的竞争日趋激烈,国际饭店集团的出现使国际旅游市场和饭店业都发生了极大的变化。与中国饭店集团相比,国际饭店集团具有诸多竞争优势,本文将以世界饭店集团300强为例,与中国饭店区域集团化特征进行对比分析,从而为中国饭店业借鉴国际饭店集团成功经验,应对其挑战提供启示。 相似文献
207.
The probability of crane living in reedy wetlands can reach 100%, at the same time, the area of reed, the water level and adjacent water area are main factors which control the crane's habitat selection. We all know that all these factors are spatially heterogeneous. For the Xianghai wetland safety and to protect the Xianghai wetland habitat of crane, this paper has mainly identified a solution to these problems. The wetland information is extracted from the TM images, which reflect the whole wetland landscape and are very important for both quantitative analysis of remote sensing observation of the earth system and positioning analysis in GIS database that is automatically extracted from DEM. The DEM for Xianghai characteristics of topography is created. On the basis of the GRID SUBMODULE, applying the GIS spatial overlay analysis, the relationship between the water level and the reed area below the water level and the rating distribution maps of reed area above water level is established. When the water level reaches the altitude of 165 m, the reed area, 981.2 ha is maximum, i.e., the water level of 165 m is the optimal. 相似文献
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