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根据中国境内2 257个气象站点1998-2013年逐日降水资料,结合流域分区,采用探测准确性、相关系数以及相对误差等指标,对热带降水测量（TRMM）降水精度和一致性进行系统评价。结果表明:① TRMM日降水准确性从东南沿海向西北内陆递减;② 气象站点年均降水日数显著大于TRMM年均降水日数;③ 西北片区以外气象站点降水量和TRMM降水量在月尺度和年尺度上均具有较好的相关关系;④ 各流域年均TRMM面降水量均高于气象站点面降水量,且TRMM面降水量相对误差雨季较小,枯季较大;⑤ 各流域TRMM面降水量与气象站点面降水量演变趋势基本一致,南方各流域年降水量均呈减少趋势,北方各流域年降水量均呈增加趋势,全国尺度上年降水量呈微弱的减少趋势。 相似文献
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黄淮海流域旱涝时空分布及组合特性 总被引：1，自引：0，他引：1
以黄淮海流域及其周边地区204个气象站点1961-2010年逐日降水过程资料、国家1:25万DEM数据和1:20万土地利用数据为基础,在利用降水Z指数对黄淮海流域旱涝进行评价的基础上,采用下垫面数据对结果进行修正,并分析黄淮海流域旱涝面积的时间变化特征,对黄淮海地区的易旱区、易涝区进行了划分,进一步选取集对分析法划分了流域内季节间旱涝交替的易发区。结果表明:黄淮海流域内夏秋两季旱涝问题较为严重,且秋旱面积上升趋势较为明显;黄河和海河流域以干旱居多,淮河则是干旱和雨涝并存,季节间的旱涝交替多集中在淮河流域中上游地区。 相似文献
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The major hydrological factors in lake-marsh systems are water level (depth), water surface area, and water volume. The key index for determining the lake-marsh pattern is water level, which leads to the variation of lake-marsh patterns under natural hydrological alternations. In addition, the vegetation structure also affects the lake-marsh pattern. With socioeconomic development and climate change, the ‘land use’ and ‘water use’ competitions appear more seriously between a lake-marsh system and its surrounding socioeconomic system, also inside the lake-marsh system. The possible optimal lake-marsh pattern could solve the contradictions mentioned above. As few studies focus on this issue, this study proposed an optimal lake-marsh pattern determination method with eco-hydrological management on relieving the land use and water use competitions. The optimal lake-marsh pattern determination method considers the protection objects (water depth demands), water supply (precipitation, surface water, and groundwater), and water demand (especially evapotranspiration) in the system at annual and monthly scales. Calculation and analysis were performed for the optimal pattern of the Wolonghu Wetlands as an example. The results mainly showed that the lake-marsh pattern of the Wolonghu Wetlands cannot be achieved on meeting both the maximum ecological services values and minimum water shortage amount under present natural condition. With artificial regulation measures, the possible optimal annual lake-marsh patterns can be obtained based on both ecological and hydrological objectives, with the area ratio of lake and marsh in the range of 0.650:0.350 and 0.726:0.274, the corresponding water level of lake body was of 86.85 to 87.0 m. This study could provide references for the Wolonghu Wetlands management, also for similar lake-marsh systems and other ecological systems. 相似文献
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Baisha Weng Wuxia Bi Zhixuan Zhao Ting Xu Dengming Yan 《Arabian Journal of Geosciences》2018,11(16):469
Based on the experimental data collected from 2002 to 2010 in Jilin province, we performed multifractal analysis to investigate the spatial variability of soil moisture during 9 years from 2002 to 2010 and about 60 days from April 21 to June 21 in 2010, and analyzed the relationship between soil moisture and precipitation. The results showed that the soil moisture was multifractal. It was intermediate variability in the soil sample. From 2002 to 2010, the spatial variation of soil moisture was charactered by long distance in 2004, 2006, and 2009 and short distance in 2002, 2003, and 2008. The spatial variation of soil moisture was charactered by long distance from April 21 to May 11 and late June. It was charactered by short distance from May 11 to June 21. From April 11 to July 1, 2010, the spatial variation of soil moisture was mainly affected by the spatial variation of precipitation. From 2002 to 2010, the spatial variation of soil moisture was mainly affected by precipitation in 2006, 2009, and 2010. The spatial variation of precipitation had little effect on soil moisture during 2002 to 2005 and 2007 to 2008. This study analyzed the multifractal characteristic of soil moisture from the perspective of water resources divisions, which can provide references for soil water resources evaluation and water resources allocation. 相似文献
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探究变化环境下全球陆地地表水资源演变特征，是当前水文与水资源学研究关注的热点与难点问题。其中，提高无资料地区水文预报的精度是准确评价全球地表水资源量的重要前提。针对这个问题，本研究在划分全球气候-生态分区的基础上，通过对5种参数移植方法进行比较优选，发现反距离空间插值法与物理相似法相结合的模拟精度最高，进而以此评价了1960—2016年全球、各大洲和重点地区的地表水资源量演变特征。结果表明：在柯本气候分区的基础上，利用生态分区指标进行无监督分类，共获得了229个气候-生态分区；基于全球降水数据和四级水资源区产水系数，获得全球多年平均地表水资源量为41.06万亿m3，与已有研究结果类似；全球、北美洲和非洲的地表水资源量呈现显著下降趋势；地表水资源量呈下降趋势的四级水资源区主要分布在北美洲、南美洲北部和非洲中部等地区。 相似文献
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从时间和空间尺度梳理了土壤团聚体的发展历程,通过分析发文时间、发文国家和地区以及关键词等把握土壤团聚体的研究方向、热点和发展趋势。近10年来,土壤团聚体的研究方向主要集中在气候变化背景下土壤有机碳对土壤团聚体稳定性的影响机制,以及土壤团聚体在缓解土壤侵蚀、风蚀和重金属污染等方面的作用。土壤团聚体研究的热点是不同土地管理制度或者不同土地利用方式对土壤团聚体稳定性的影响机制,以及土壤团聚体在碳循环中的作用。同时发现对土壤团聚体的研究高度集中在中低纬度、中低海拔地区,而对高纬度、高海拔地区关注不够。未来土壤团聚体的研究仍会在气候变化背景下展开：(1)研究其与土壤有机碳的相互作用机制,充分发挥其固碳潜力;(2)研究其与土壤水分的关系,探究其对不同尺度水循环的影响;(3)在高纬度、高海拔地区进一步开展深层次和外延性的研究。 相似文献
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Dorjsuren Batsuren Batsaikhan Nyamdavaa Yan Denghua Yadamjav Otgonbayar Chonokhuu Sonomdagva Enkhbold Altanbold Dorligjav Sandelger Wang Kun Weng Baisha Qin Tianlin 《Water Resources》2022,49(1):46-57
Water Resources - This study used the Innovative trend analysis method, Mann-Kendall, and Sen’s slope estimator test to investigate the mean annual precipitation, annual mean air temperature,... 相似文献
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Drought is an extreme event in hydrologic cycle. The occurrences of drought events usually feature determinacy and randomness. With the increasing impact of climate change and anthropogenic activities, drought happens in more areas with higher frequency, and now it threatens the water and ecology security in river basin. Drought is firstly a resource issue, and with its development, it transforms into a disaster issue. From the perspective of the water resources system, the Dongliao River Basin, which has high frequency of drought occurrence, was studied to propose the connotation and the quantitative evaluation method of generalized drought. The driving factors of natural climate variability (NCV), anthropogenic climate change (ACC), underlying condition change and hydraulic engineering regulation (HER) can alter the impacts of drought events. The influencing time of NCV, ACC and HER was decided, respectively, and generalized drought risk maps were drawn. Finally, water emergency dispatch, water demand compression and water diversion were proposed to cope with the generalized drought risk. 相似文献