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91.
Maki Tsujimur Koichi Ike Tadashi Tanak Lunten Janchivdorj BadamgaravErdenchimeg Damdinbazar Unurjargal Ramasamy Jayakumar 《寒旱区科学》2013,5(1):0126-0132
Drinking water supplies in Ulaanbaatar, the capital of Mongolia, are completely dependent on groundwater sourced from pumping
wells located in an alluvial plain of the Tuul River which flows through Ulaanbaatar. The interaction between groundwater in the
alluvial plain and river surface water was investigated using a hydrological and multi-tracers approach. The observed groundwater
contour map clearly shows that the Tuul River recharges the floodplain groundwater and groundwater flows from east to west.
The similarity of chemical and stable isotopic compositions suggests that groundwater is mainly recharged by Tuul River water in
the vicinity of the river. In addition, considering groundwater contours and chemical composition, groundwater in the northern and
southern mountain sides contribute to floodplain groundwater. Stable isotopic information suggests that winter season precipitation
also contributes to the groundwater, because groundwater in a specific region has a considerably lower isotopic ratio. Using
the End Member Mixing Analysis applying oxygen-18, SiO2 and HCO3
- as tracers, the contribution ratios of the Tuul River,
groundwater in the northern and southern mountain regions, and winter season precipitation to floodplain groundwater are estimated
to be 58% to 85%, 1% to 54%, 0% to 16%, and 0% to 12%, respectively. 相似文献
92.
93.
James Glimm Shuling Hou Hongjoong Kim Yoon-ha Lee David H. Sharp Kenny Ye Qisu Zou 《Computational Geosciences》2001,5(3):173-197
We consider numerical solutions of the Darcy and Buckley–Leverett equations for flow in porous media. These solutions depend on a realization of a random field that describes the reservoir permeability. The main content of this paper is to formulate and analyze a probability model for the numerical coarse grid solution error. We explore the extent to which the coarse grid oil production rate is sufficient to predict future oil production rates. We find that very early oil production data is sufficient to reduce the prediction error in oil production by about 30%, relative to the prior probability prediction. 相似文献
94.
基于多源遥感数据提取投入产出数据,采用考虑非期望产出的超效率EBM模型对2000—2015年山东省县域生态效率进行测度,在此基础上采用核密度估计、空间自相关等方法对山东省县域生态效率的时空特征进行分析。研究表明:①山东省县域生态效率呈现波动式发展趋势;高值区与低值区存在显著空间分化,胶东半岛与济南都市圈构成高值集聚区,鲁西北、鲁西南、鲁南地区形成低值连绵带;②山东省县域生态效率无明显的两极分化现象,处于高值区、低值区的县域生态效率值变化较大,生态效率空间非均衡性逐渐扩大;③山东省县域生态效率存在显著空间正相关,且空间集聚性呈现增强态势;县域生态效率存在空间俱乐部趋同特征。 相似文献
95.
社交媒体数据在自然灾害应急管理中的应用研究综述 总被引:1,自引:1,他引:1
社交媒体是灾害应急管理的一个新兴但尚未充分利用的大数据源。然而,社交媒体数据在灾害应急管理中能发挥什么作用,目前国内的研究较少,而国外的研究亦较为分散,相关应用受限。论文对国内外利用社交媒体数据进行灾害管理相关研究进行了综述,归纳出社交媒体数据在灾害应急管理中应用的潜力、优势和问题。结果发现:① 社交媒体数据含有丰富的灾害信息,能够依靠态势感知和信息共享支持灾害预警、实时监测、损失和救助需求评估、协助快速应急响应以及预测可能的灾害风险等灾害管理工作;② 社交媒体数据的优势在于能保证灾害信息的实时性和连续性,进而提供致灾强度图、损失预测和舆情分析等结果服务于灾害应急管理;③ 地理位置信息有限、专业语料库缺乏、信息噪声处理的复杂性等原因使社交媒体数据分析结果精度受限。如何发挥社交媒体数据社会感知的优势,以弥补传统观测调查手段的不足,更加科学应对灾害应急,仍需要在社交媒体数据处理及多源数据融合分析技术方面取得突破。 相似文献
96.
The circulation and salinity distribution in the Hooghly Estuary have been studied by developing a two‐dimensional depth‐averaged numerical model for the lower estuary, where the flow is vertically well mixed. This has been coupled with a one‐dimensional model for the upper estuary, where the flow is assumed to be unidirectional and well mixed over the depth and breadth. The Hooghly River receives high freshwater discharge during the monsoon season (June to September), which has significant effect on the salinity distribution in the estuary. The model‐simulated currents, elevations, and salinities are in good agreement with observations during the dry season. However, during the wet season the computed salinities seem to deviate slightly from the observed values. 相似文献
97.
乌鲁木齐河灌区水资源利用及可持续管理 总被引:2,自引:0,他引:2
通过对乌鲁木齐河灌区历年供水和用水状况分析,提出了该灌区水资源可持续利用的对策,并针对城市用水逐年增加与水资源供需矛盾日益突出的形势,从水份分析入手,从水资源可持续管理的角度,提出了水资源高效利用与管理的对策 。 相似文献
98.
Riparian vegetation provides important wildlife habitat in the southwestern United States, but limited distributions and spatial complexity often leads to inaccurate representation in maps used to guide conservation. We test the use of data conflation and aggregation on multiple vegetation/land-cover maps to improve the accuracy of habitat models for the threatened western yellow-billed cuckoo (Coccyzus americanus occidentalis). We used species observations (n = 479) from a state-wide survey to develop habitat models from 1) three vegetation/land-cover maps produced at different geographic scales ranging from state to national, and 2) new aggregate maps defined by the spatial agreement of cover types, which were defined as high (agreement = all data sets), moderate (agreement ≥ 2), and low (no agreement required). Model accuracies, predicted habitat locations, and total area of predicted habitat varied considerably, illustrating the effects of input data quality on habitat predictions and resulting potential impacts on conservation planning. Habitat models based on aggregated and conflated data were more accurate and had higher model sensitivity than original vegetation/land-cover, but this accuracy came at the cost of reduced geographic extent of predicted habitat. Using the highest performing models, we assessed cuckoo habitat preference and distribution in Arizona and found that major watersheds containing high-probably habitat are fragmented by a wide swath of low-probability habitat. Focus on riparian restoration in these areas could provide more breeding habitat for the threatened cuckoo, offset potential future habitat losses in adjacent watershed, and increase regional connectivity for other threatened vertebrates that also use riparian corridors. 相似文献
99.
100.
为了解塔里木河下游生态输水量与地下水埋深多年响应变化过程,得出地下水埋深对生态输水的响应变化规律,以塔里木河下游英苏断面为研究区,运用定性与定量分析方法,综合考虑不同输水差异(包括零输水年即2008年、输水极少年即2009年、输水较多年2011年等),对2000-2015年英苏断面1 050 m范围内地下水埋深数据进行了分析。结果表明:研究断面内地下水埋深在各年份总体呈现比较平稳的递减趋势,年内个别月具有较大的增幅,另外由于冻土消融等因素影响,地下水埋深在2~3月有一定的增幅;离河较近区域的地下水埋深变化对生态输水的响应具有时间同步性,而离河道较远地区的地下水埋深在响应时间上存在滞后性,本研究断面1 050 m范围内地下水埋深响应时间维持在1 a内;经过多年生态输水过程,英苏监测断面距离河道约750 m范围内地下水平均埋深维持在2~6 m范围内,基本达到植物生长所需地下水埋深水平;另外,综合分析研究断面多年输水引起的地下水位响应过程,为获得生态输水过程所带来的最大生态效益,生态输水不仅要保持一定的输水量,还要保持输水年周期的连续性。 相似文献