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Water resources in semi-arid regions like the Mediterranean Basin are highly vulnerable because of the high variability of weather systems. Additionally, climate change is altering the timing and pattern of water availability in a region where growing populations are placing extra demands on water supplies. Importantly, how reservoirs and dams have an influence on the amount of water resources available is poorly quantified. Therefore, we examine the impact of reservoirs on water resources together with the impact of climate change in a semi-arid Mediterranean catchment. We simulated the Susurluk basin (23.779-km2) using the Soil and Water Assessment Tool (SWAT) model. We generate results for with (RSV) and without reservoirs (WRSV) scenarios. We run simulations for current and future conditions using dynamically downscaled outputs of the MPI-ESM-MR general circulation model under two greenhouse gas relative concentration pathways (RCPs) in order to reveal the coupled effect of reservoir and climate impacts. Water resources were then converted to their usages – blue water (water in aquifers and rivers), green water storage (water in the soil) and green water flow (water losses by evaporation and transpiration). The results demonstrate that all water resources except green water flow are projected to decrease under all RCPs compared to the reference period, both long-term and at seasonal scales. However, while water scarcity is expected in the future, reservoir storage is shown to be adequate to overcome this problem. Nevertheless, reservoirs reduce the availability of water, particularly in soil moisture stores, which increases the potential for drought by reducing streamflow. Furthermore, reservoirs cause water losses through evaporation from their open surfaces. We conclude that pressures to protect society from economic damage by building reservoirs have a strong impact on the fluxes of watersheds. This is additional to the effect of climate change on water resources. 相似文献
23.
The Lower Mississippi Alluvial Valley (LMAV) was home to about ten million hectare bottomland hardwood (BLH) forests in the Southern U.S. It experienced over 80 % area loss of the BLH forests in the past centuries and large-scale afforestation in recent decades. Due to the lack of a high-resolution cropland dataset, impacts of land use change (LUC) on the LMAV ecosystem services have not been fully understood. In this study, we developed a novel framework by integrating the machine learning algorithm, county-level agricultural census, and satellite-based cropland products to reconstruct the LMAV cropland distribution during 1850–2018 at a 30-m resolution. Results showed that the LMAV cropland area increased from 0.78 × 104 km2 in 1850 to 6.64 × 104 km2 in 1980 and then decreased to 6.16 × 104 km2 in 2018. Cropland expansion rate was the largest in the 1960s (749 km2 yr−1) but decreased rapidly thereafter, whereas cropland abandonment rate increased substantially in recent decades with the largest rate of 514 km2 yr−1 in the 2010s. Our dataset has three notable features: (1) the depiction of fine spatial details, (2) the integration of the county-level census, and (3) the inclusion of a machine-learning algorithm trained by satellite-based land cover product. Most importantly, our dataset well captured the continuous increasing trend in cropland area from 1930–1960, which was misrepresented by other cropland datasets reconstructed from the state-level census. Our dataset would be important to accurately evaluate the impacts of historical deforestation and recent afforestation efforts on regional ecosystem services, attribute the observed hydrological changes to anthropogenic and natural driving factors, and investigate how the socioeconomic factors control regional LUC pattern. Our framework and dataset are crucial to developing managerial and policy strategies for conserving natural resources and enhancing ecosystem services in the LMAV. 相似文献
24.
综合采用岩心、薄片和成像测井等资料,对库车坳陷克深气田白垩系巴什基奇克组构造裂缝的形成序列、分布规律和影响因素进行了研究。结果表明:剪切裂缝和张性裂缝在克深气田均有发育,以直立缝和高角度缝为主,主要形成于近南北向的挤压作用、背斜弯曲拱张作用和异常流体高压作用,微观裂缝切穿胶结物和部分颗粒,早期充填构造裂缝可在后期构造应力和异常流体高压作用下重新裂开成为有效裂缝。克深气田发育3期构造裂缝,其中第3期构造裂缝的形成时间与天然气大量充注期吻合,是工业规模性气藏形成的关键因素。单个断背斜高部位的构造应力低于背斜翼部,因此背斜高部位的构造裂缝线密度相对较低,但背斜弯曲变形使裂缝开度较大,有效性好,单井的无阻流量较高;翼部和断层附近构造裂缝线密度较大,但开度较小,有效性差;构造应力、岩石强度和变形时间的不同造成了构造裂缝特征在各气藏之间具有差异性。储层中部第3砂层组的构造裂缝发育程度中等,充填程度相对较低,并且平面上分布连续,可形成连片分布的储层“甜点”区,应成为克深气田开发中的重点层位。对克深气田构造裂缝起主要贡献作用的为水下分流河道和河口坝微相的粉‒细砂岩。 相似文献
25.
中国石化枯竭气藏型储气库注采技术及发展建议 总被引:1,自引:0,他引:1
经长输管线输送的天然气注入到地下空间而形成的人工气藏称为地下储气库。国内外现有储气库大多数是枯竭气藏型地下储气库。中国石化储气库建设起步较晚,基础较为薄弱,同时与国内外已建成储气库相比,中石化储气库建设面临的地质条件和注采工况也较为复杂。以中国在建最大储气库项目中原文23储气库为例,其复杂地质条件以及面临的"快瞬变非稳态增压"注采难题需要进行专门研究。分析了目前中石化枯竭型气藏储气库建库现状,提出了建库技术挑战,总结了现阶段取得的注采关键技术研究成果,通过分析中国石化枯竭气藏型储气库注采技术研究现状和最新进展,提出了国产化技术完善、智能化注采营运、一体化模拟实验室的建设等方面的发展建议和要求,为持续加强规模化储气库群建设的支持提供参考。 相似文献
26.
2018年伏秋汛期黄河流域上游持续来水,为保证2108-2019年度黄河流域凌汛期安全,黄河流域重点水库进行了大流量持续下泄。以2018年9月的实际数据为基准,通过对重点水库实际日均出入库调度情况,内蒙古河段的重点水文站实际日均流量过程和三个年份汛期大断面套绘成果对比分析研究,可以得出水库大流量持续下泄对内蒙古河段河道塑形能力起到了关键性作用,有效的提高了主槽过流能力,河段最小平滩流量得到一定的恢复,对下一步研究黄河流域河道过流能力提供了有利的数据支撑和参考价值。 相似文献
27.
正20141967An Zhanghui(Lanzhou Base of Institute of Earthquake Prediction,CEA,Lanzhou 730000,China);Du Xuebin Study onthe Geo-Electric Field Variation of Sichuan Lushan MS7.0and Wenchuan MS8.0Earthquake(Chinese Journal of Geophysics,ISSN0001-5733,CN11-2074/P,56(11), 相似文献
28.
正20141074Bao Xijie(Research Institute of Exploration and Development,Daqing Oilfield Company,PetroChina,Daqing 163712,China)Gather Optimal Processing and Application Effect of Prestack AVA Instantaneous Inversion 相似文献
29.
正1.HYDROGEOLOGY20142452Chang Chengcao(Institute of Coalfield Geological Survey and Design of Jilin Province,Changchun 130062,China)Hydrogeological Type Division of Coal Mine No.2Mine in Yitong Manchu Autonomous County,Jilin Province(Jilin Geology,ISSN1001-2427,CN22-1099/P,32(4),2013,p.129-131,3refs.) 相似文献
30.
正20142114Lin Quansheng(China University of Geosciences,Bejing 100083,China)On the Geologic Characteristics and Economic Significance of the Cambrian Lintian Group in Fujian Province(Geology of Fujian,ISSN1001-3970,CN35-1080/P,32(4),2013,p.264-273,2illus.,2tables,6refs.) 相似文献