京津冀城市群虚拟水贸易的近远程分析   总被引：2，自引：0，他引：2  

孙思奥  郑翔益  刘海猛 《地理学报》2019,74(12):2631-2645

虚拟水贸易能重新分配区域间的水资源。在京津冀协同发展的背景下,厘清京津冀城市群与外部的虚拟水贸易及城市群内部的虚拟水流动,有助于深入理解该地区的水资源供需现状及问题,为制定虚拟水贸易相关策略、实现区域水资源优化配置、保障区域水资源安全提供决策支持。本文基于2010年全国区域间投入产出表,测算了京津冀城市群各省（市）水足迹及与全国各省域单元的虚拟水贸易量。从近远程视角定量评估城市群地区对内、外部水资源的依赖程度,并分析虚拟水贸易的距离特征。研究发现：① 京津冀城市群各省（市）各部门用水系数显现出差异性,农业部门用水强度最高,直接用水与完全用水系数分别超过300 m ³/万元和400 m ³/万元;② 京津冀城市群内部各省（市）人均消费水足迹差异大,北京、天津、河北的人均水足迹分别为405 m ³、565 m ³、191 m ³;③ 京津冀城市群的消费水足迹遍布全国各省域单元,近程水足迹与远程水足迹分别为91.4亿m ³、198.5亿m ³,其中,近程水足迹主要来源于本省（市）,西部地区对远程水足迹的贡献最大;④ 京津冀城市群的虚拟水输入总体偏向来源于距离较近的省域单元,北京、天津、河北水足迹距离来源地的平均距离分别为1049 km、1297 km、688 km;⑤ 北京和天津为虚拟水贸易的净流入区,对外部水资源的依赖性强;河北为虚拟水贸易的净流出区,为京津冀城市群及其他地区供给水资源,虚拟水净流出进一步加剧了河北的水资源短缺。未来,受人口增长、经济发展等因素影响,京津冀城市群的水资源压力将进一步加剧,提高用水效率、升级产业结构、提倡低水足迹消费模式、实行虚拟水战略是实现京津冀城市群可持续发展的有效途径。  相似文献   

Developing a comprehensive evaluation method for Interconnected River System Network assessment: A case study in Tangxun Lake group     

Yang  Wei  Zhang  Liping  Zhang  Yanjun  Li  Zongli  Xiao  Yi  Xia  Jun 《地理学报(英文版)》2019,29(3):389-405

Journal of Geographical Sciences - The Interconnected River System Network (IRSN) plays a crucial role in water resource allocation, water ecological restoration and water quality improvement. It...  相似文献   

A comparative study of the hopanoid hydrocarbons in sediments of two lakes (Fuxian and Changdang) with contrasting environments     

《Limnologica》2019

Biologically configured ββ-hopanes, geologically configured αβ-hopanes and the biogenic hopenes were determined in dated sediment cores from Lake Fuxian in SW China and Lake Changdang in Eastern China in order to investigate anthropogenic influences on the abundance, composition and provenance of hopanoid hydrocarbons in lake sediments. Based on the results, hopenes were prevalent, with maximum values reaching 148.9 μg g⁻¹ TOC in sediments of Lake Fuxian, an oligotrophic deep lake (average depth 89.6 m), where the long water column provided ample potential for the growth of hopene-producing bacteria especially the cyanobacteria. Sediment hopenes have diminished in abundance to values of 13.4–78.5 μg g⁻¹ TOC in Lake Changdang, a eutrophic shallow (average 0.8–1.2 m) body, reflecting comparatively reduced importance of nutrient level on hopene production. Historical trends in hopenes input to the sediments of each lake are strongly dependent on nutrient status. During the last few decades, human-induced eutrophication has greatly boosted bacterial production, enhancing the accumulation of hopenes in sediments. Inputs of petroleum-derived αβ-hopanes were exceptionally high (average 71.2 μg g⁻¹ TOC) in post-1968 sediments from Lake Changdang, their increase coinciding with the advent and acceleration of petroleum product use around the lake, in particular by fishing boats. Lake Fuxian on the other hand, has undergone slower economic development and the appearance of petroleum-derived αβ-hopanes in sediments was delayed to 1990 since when the average value has been 27.1 μg g⁻¹ TOC. The abundance of αβ-hopanes in Lake Changdang has created a marked decrease in the relative contribution of hopenes to total hopanoids since 1968. Conversely, the amounts of αβ-hopanes introduced to Lake Fuxian since 1990 has yet to yield a clear change in the overall proportion of hopenes, but the abundance of ββ-hopanes has declined relative to total hopanoid levels for the period.  相似文献   

京津冀协同治理的回顾与前瞻   总被引：1，自引：0，他引：1  

崔丹  吴昊  吴殿廷 《地理科学进展》2019,38(1):1-14

京津冀区域治理是伴随三地协作发展的进程,从政府层面的管制转向各利益主体协调治理,从自上而下的竞争合作转向上下结合的协同合作的一系列有效应对举措。经过30多年的努力,学界和政府部门已经形成了较为丰富的京津冀区域治理研究成果。通过梳理自1984年以来相关区域的研究,尝试从时空维度厘清京津冀区域治理的研究脉络及其变化,剖析目前京津冀区域治理所涉及的治理模式、协调体系、以及形成的发展策略,为改进和提高京津冀区域治理效果提供参考。京津冀协同治理过程是学术界与政府的互动融合过程,其中政府的作用居主导地位。未来将在治理主体、治理机制、治理效果评价和文化、医疗、养老等领域的协调发展方面得到深化和细化。  相似文献   

过去40年太湖剧烈的湖泊物理环境变化及其潜在生态环境意义     

张运林  秦伯强  朱广伟 《湖泊科学》2020,32(5):1348-1359

过去40年,全球气候变暖、辐射变暗和变亮、风速减弱、气候异常波动等自然环境变化以及筑坝建闸、岸堤硬质化和调水引流等强烈人类活动势必会深刻改变太湖湖泊物理环境和过程,驱动湖泊生态系统演化.基于历史文献、档案数据以及气象水文和透明度等长期观测数据,本文系统梳理了太湖气温、水温、风速、水位和透明度等物理环境空间分布和长期变化特征,探讨了气温和风速、水位和透明度相互协同作用机制及其潜在生态环境意义.受全球变化和城市化等影响,过去40年太湖气温和水温呈现显著升高趋势,而近地面风速则表现为持续下降,湖泊增温和风速下降有利于藻类生长和蓝藻水华漂浮聚集,某种程度上增加了蓝藻水华出现频次和集聚的面积.为防洪和满足流域日益增长的水资源需求,闸坝管控和调水引流使太湖水位呈现缓慢增加趋势,而入湖污染物增加和富营养化则造成水体透明度逐渐下降,致使透明度与水位(水深)的比值明显降低,减少了湖底可利用光强,恶化水下光环境,在一定程度上驱动了太湖水生植被和草型生态系统退化.湖泊物理环境长期变化逐渐拓展了太湖藻型生境空间而压缩了草型生境空间,加剧了草型生态系统向藻型生态系统转化和增强了藻型生态系统的自我长期维持.太湖湖泊物理环境的显著变化也会部分抵消流域营养盐削减和湖体营养盐下降对藻类生物量和蓝藻水华的控制,增加了太湖蓝藻水华防控和湖泊富营养化治理的难度.这意味着未来流域控源截污需要更加严格的标准,而湖泊水位等物理环境的有效管控是应对藻华加剧和恢复草型生态系统的适应性管理策略.  相似文献   

Landsat长时间序列的阳澄湖湖面围网时空变化     

计璐艳  尹丹艳  宫鹏 《遥感学报》2019,23(4):717-729

准确提取湖泊围网区域的时空分布信息对湖泊的保护和可持续发展具有重要意义。本文以阳澄湖为研究区域,收集该地区1984年—2017年所有的Landsat 5和Landsat 8影像(共计396景),提出了结合光谱和纹理特征的围网提取新算法,同时利用时间序列滤波消除年际间因数据不一致造成的偏差。以高清影像人工解译作为参考,阳澄湖围网提取结果的生产者精度在72.57%—88.53%,用户者精度在79.79%—98.10%,围网面积变化与文献记录吻合。结果表明,阳澄湖围网经历了"无围网期"(1984年—1994年)、"快速增长期"(1994年—1998年)、"巅峰期"(1999年—2002年)、"快速下降期"(2003年—2006年)和"稳定期"(2007年—2017年)5个阶段,最高达到100 km2,目前稳定在30 km2;通过研究围网区植被指数发现,2002年之后围网区浮水植物的种植面积增大;通过对比水质数据发现,2002年至今持续15年的围网拆除并未使阳澄湖恢复到80年代无围网养殖时期的II类水,其水质依然处于Ⅲ—Ⅳ类。因此在湖泊养殖开发过程中,政府应该坚持可持续发展道路,在不破坏湖泊水质的基础上发展湖泊经济。  相似文献   

蒸发波导对GNSS海面反射信号有效散射区域的影响          下载免费PDF全文

刘黎军  夏俊明  白伟华  孙越强  杜起飞  骆黎明 《地球物理学报》2019,62(2):499-507

蒸发波导在海洋低空的发生概率高达90%,对舰船雷达、通信等电磁系统具有重要影响.为了分析利用GNSS卫星海面反射信号的时延-相关功率波形反演蒸发波导的可行性,本文提出了GNSS卫星海面反射信号的有效散射区域的概念,并将有效散射区域内的GNSS反射信号区分为GNSS标准反射信号和GNSS波导反射信号;然后,利用射线追踪方法,仿真分析了GNSS卫星海面反射信号的有效散射区域大小对蒸发波导的关键参数——波导高度的敏感性,并分析了在时延-相关功率波形上利用反射信号的传播时延将二者分离开的可行性.结果表明,GNSS卫星海面反射信号的有效散射区域对蒸发波导高度非常敏感,对于2～25m高的GNSS反射信号接收天线,当蒸发波导的高度由0m增加至20m时,GNSS反射信号有效散射区域半径的均值可由约14km迅速扩展至约160km;采用高度角足够大的GNSS卫星可以将有效散射区内的GNSS标准反射信号与GNSS波导反射信号在时延-相关功率波形上分离开.  相似文献   

盐源—宁蒗地区早泥盆世古地理特征及油气潜力分析     

邓敏  程锦翔  王正和  余谦  张海全  张娣  陆俊泽 《沉积与特提斯地质》2020,40(4):25-35

为了探索康滇地轴以西地质条件复杂地区的油气资源潜力，通过面积性地质调查工作与钻孔资料、分析测试资料结合，对盐源—宁蒗地区下泥盆统黑色页岩开展综合研究。研究表明：盐源—宁蒗地区早泥盆世古地理主要受康滇古陆及古特提斯构造域的构造活动控制，靠近金-箐断裂地区发育滨岸-潮坪相，古隆起围限区出现局限海湾相，远离隆起的西北部地区发育台地、陆棚、盆地相；大瓜坪组（早泥盆世晚期）发育黑色页岩（局部地区发育硅质泥岩），在羊排喜—岩口一带分布较为稳定、厚度大（20～100m），普遍含钙质，有机碳含量较高，具较高的脆性矿物含量，热演化程度适中，是重要的烃源岩和页岩气富集有利层位；黑色页岩主要发育在局限海湾环境中，羊排喜—岩口—茅坪子一线是盐源—宁蒗地区黑色页岩富集区。  相似文献   

Acceleration of vegetation dynamics in hydrologically connected wetlands caused by dam operation     

Lilin Zheng  Jinying Xu  Dandan Wang  Guoyu Xu  Zhiqiang Tan  Ligang Xu  Xiaolong Wang 《水文研究》2021,35(2):e14026

The dynamic responses of wetlands to upstream water conservancy projects are becoming increasingly crucial for watershed management. Poyang Lake is a dynamic wetland system of critical ecological importance and connected with the Yangtze river. However, in the context of disturbed water regime in Poyang Lake resulting from human activities and climate change, the responses of vegetation dynamics to the Three Gorges Dam (TGD) have not been investigated. We addressed this knowledge gap by using daily water level data and Landsat images from 1987 to 2018. Landsat images were acquired between October and December to ensure similar phenological conditions. Object-oriented Artificial Neural Network Regression for wetland classification was developed based on abundant training and validation samples. Interactions between vegetation coverage and water regimes pre and post the operation of the TGD were compared using classification and regression trees and the random forest model. Since the implementation of the TGD in 2003, Poyang Lake has become drier, especially during the dry season. A more rapid plant growth rate was observed post TGD (44.74 km² year⁻¹) compared to that of the entire study period (12.9 km² year⁻¹). Average water level for the antecedent 20 days most significantly affected vegetation before 2003, whereas average water level for the antecedent 5 or 10 days was more important after 2003. The impoundment of the TGD after the flood season accelerated the drawdown processes of Poyang Lake, and the rapidly exposed wetlands accelerated vegetation expansion during the dry seasons, resulting in shrinkage and degradation of the lake area. This study deepens our knowledge of the influences of newly developed dams on lakes and rivers.  相似文献   

Understanding the hydrological system dynamics of a glaciated alpine catchment in the Himalayan region using the J2000 hydrological model          下载免费PDF全文

S. Nepal  P. Krause  W.‐A. Flügel  M. Fink  C. Fischer 《水文研究》2014,28(3):1329-1344

This paper provides the results of hydrological modelling in a mesoscale glaciated alpine catchment of the Himalayan region. In the context of global climate change, the hydrological regime of an alpine mountain is likely to be affected, which might produce serious implications for downstream water availability. The main objective of this study was to understand the hydrological system dynamics of a glaciated catchment, the Dudh Kosi River basin, in Nepal, using the J2000 hydrological model and thereby understand how the rise in air temperature will affect the hydrological processes. The model is able to reproduce the overall hydrological dynamics quite well with an efficiency result of Nash–Sutcliffe (0.85), logarithm Nash–Sutcliffe (0.93) and coefficient of determination (0.85) for the study period. The average contribution from glacier areas to total streamflow is estimated to be 17%, and snowmelt (other than from glacier areas) accounts for another 17%. This indicates the significance of the snow and glacier runoff in the Himalayan region. The hypothetical rise in temperature scenarios at a rate of +2 and +4 °C indicated that the snowmelt process might be largely affected. An increase in snowmelt volume is noted during the premonsoon period, whereas the contribution during the monsoon season is significantly decreased. This occurs mainly because the rise in temperature will shift the snowline up to areas of higher altitude and thereby reduce the snow storage capacity of the basin. This indicates that the region is particularly vulnerable to global climate change and the associated risk of decreasing water availability to downstream areas. Under the assumed warming scenarios, it is likely that in the future, the river might shift from a ‘melt‐dominated river’ to a ‘rain‐dominated river’. The J2000 model should be considered a promising tool to better understand the hydrological dynamics in alpine mountain catchments of the Himalayan region. This understanding will be quite useful for further analysis of ‘what‐if scenarios’ in the context of global climate and land‐use changes and ultimately for sustainable Integrated Water Resources Management in the Himalayan region. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献