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1.
长江流域历史水旱灾害分析   总被引:2,自引:1,他引:1  
黄忠恕  李春龙 《湖泊科学》2003,15(Z1):210-215
长江流域有丰富和长期的水旱灾害史料,最早的水灾和旱灾记载有2000余年的历史,经过系统整理和分析的历史水旱灾害资料有1000余年的旱涝型年表和500余年的旱涝分布图集.在以上资料基础上,对长江流域历史水旱灾害的地域分布特性和时间变化规律进行了初步分析:500余年历史水旱灾害的地域分布显示,流域水旱灾害总体特征是水灾重于旱灾,各级水旱灾害频率的地域分布极不均匀,存在着显著的灾害多发和少发地带,它们与自然地理环境、水系特征、气候条件和社会经济条件等因素有关;1000余年旱涝型年表分析表明,长江流域洪涝和干旱频次在时间上的非均匀分布并非完全随机,表现出多种时间尺度的年际变化特征,其中主要表现为约100a上下的大干湿气候期变化及40a左右的小旱涝期振动.  相似文献   

2.
Water Resources - In the comprehensive management of watersheds, the knowledge of the sedimentation process in flood conditions is considered as an important and challenging issue. The aim of this...  相似文献   

3.
崔伟中 《湖泊科学》2004,16(Z1):77-82
流域管理是以水资源的自然流域特性和多功能属性为基础的管理制度,它的目标是使有限的水资源实现优化配置和发挥最大效益.流域管理的问题直接关系到以水资源的可持续利用支持经济社会的可持续发展的大局.通过分析我国流域管理存在的问题,借鉴国外成功的流域管理经验,提出要进一步明确流域管理和行政区域管理的事权,加快流域管理相应的法律法规建设,加大流域管理的支撑保障能力建设,充分发挥流域管理机构科学规划决策、有效配置调控和有力监督控制的作用,进一步探索适合不同流域的管理模式,加大构建公共参与和民主协商机制力度,探索建立流域水资源管理可持续利用的市场机制.  相似文献   

4.
Water Resources - The aim of this study is to apply mathematical modeling to describe the hydrological regime of small testbed catchments located in the territory of the Verkhne-Ussuriisky...  相似文献   

5.
6.
通过对太湖流域处于工业化不同发展阶段的两个城市进行对比,揭示了工业化与工业废水排放之间的关系.分析表明:工业化发展阶段不同,所对应的经济规模和产业结构不同,导致其工业废水排放量与水环境质量不同.目前,无锡市处于工业化的中后期阶段,虽然其工业废水排放水平随人均收入增加在逐渐减少,但是无锡市的水环境污染状况依然严重;湖州市处于工业化加速上升阶段,虽然其工业废水排放水平随人均收入的增加而逐步增加,但是湖州市水环境污染相对较轻.这是因为水环境质量不仅受工业污染源的影响,还受生活污染和农业面源污染的影响,同时还受当地水环境容量的制约.  相似文献   

7.
Statistical methods of data analysis have been used to study the correlation between the benthic characteristics and the geochemical and toxicological characteristics of bottom sediments of the small river of Sestra. As shown, a relatively wide scope of biological and chemical data is needed to assess the quality of bottom sediments of the Sestra River.  相似文献   

8.
Water Resources - The objective of this paper is the assessment of the effect of a multifunctional mid-size retention reservoir on the occurrence of floods and low flows. The study object was...  相似文献   

9.
我国地震动预测及地震危险性分析通常仅考虑局部场地浅层岩土层对地震动的放大效应,不能考虑较大范围的地质条件影响,如沉积盆地厚沉积层对地震动的附加放大效应通常被忽略,造成盆地内地震动及地震危险性预测结果普遍被低估。本文以地震动观测记录数据充足的日本关东盆地为例,采用地震动残差分析方法评估盆地附加放大效应,分析覆盖层厚度、盆地内空间位置、震级、震源距对地震动放大效应的影响,建立关东盆地附加放大效应经验评估模型。分析表明:关东盆地附加放大效应与反应谱周期相关,整体上从短周期的1.0逐渐增大至周期为5s时的1.5,附加放大效应与覆盖层厚度相关性较小,主要受盆地空间位置和震源距的影响;盆地北部边缘及西北部地区附加放大效应更强烈,盆地南部附加放大效应较小,这可能与盆地边缘效应密切相关。本文建立的关东盆地附加放大效应经验模型略高于BSSA14和ASK14模型的放大效应预测。相关研究结果可用于我国地震动预测、下一代地震动区划图修订等。  相似文献   

10.
Groundwater is a major source of water supply for domestic and irrigation uses in semiarid, remote but rapidly developing Kilasaifullah district part of Zhob River Basin, located at Pakistan–Afghanistan Border. Zhob River is among few major rivers of perennial nature in Balochistan, which flows from WSW to ENE and falls in Gomal River, a tributary of Indus River. Keeping in view the important geopolitical position and rapid development of the region, this study is primarily focused on groundwater chemistry for contamination sources as well as agriculture development. Water samples from open and tube wells are analyzed and calculated for electrical conductivity (EC), total dissolved solids (TDS), turbidity, pH, K+, Na+, Ca2+, Mg2+, HCO, Cl?, NO, SO, PO, sodium percent (Na%), sodium adsorption ratio (SAR), Kelly's index (KI), and heavy metals (Fe, Cu, Cr, Zn, Pb, and Mn). On the basis of the chemical constituents two zones within the study area are identified and possible causes of the contaminants are pointed out. Two recharge areas were responsible for the different chemical results in groundwater, e.g., zone A was recharged from NNW saline geological formations (Nisai, Khojak, Multana, Bostan formations, and Muslim Bagh ophiolites), which are concentrated with high sodium and chloride. On the other hand Zone B was sourced from SSW from carbonate rich rocks (Alozai, Loralai, Parh formations, and Muslim Bagh ophiolites). The groundwater is classified as C2–S1, C3–S1, C3–S2, C4–S2 on the basis of EC and SAR values which indicate that most of the water of both zones can be used for irrigation safely except the samples plotted in C3–S2 and C4–S2 categories which could be dangerous for soil and crops. Groundwater samples are plotted in good to permissible limits with some samples excellent to good and few samples belong to doubtful category based on sodium percent. Groundwater of zone A is unsuitable for irrigation use due to higher values of KI (more than one) but water of zone B are good for irrigation based on KI. In general, water of both zones is suitable for irrigation but care should be taken during the selection of crops which are sensitive to alkalinity or sodium hazards particularly in zone A.  相似文献   

11.
The effect of anthropogenic pollution on the structure of benthic animal communities in the Barnaulka R. (Ob tributary) has been studied. Statistical analysis was used to assess the effect of habitat factors on macrozoobenthos structure. The structure characteristics of benthic macroinvertebrate communities and the bioindication indices calculated from them are shown to depend on the hydrophysical and hydrochemical characteristics of water and bottom sediments.  相似文献   

12.
Seismic activity, ground deformation, and soil and fumarole temperatures acquired during 2004–2007 at Vulcano (Aeolian Islands) are analysed and the time relations among the different time series are discussed. Changes in temperature of fumarolic gases took place during four “anomalous” periods (November 2004–March 2005; October 2005–February 2006; August–October 2006; July–December 2007) at the same time as an increasing number of volcano-seismic events. In particular, the temperatures at high temperature vents and at steam heated soil ranged in time from 180 to 440°C and from 20 to 90°C, respectively. The maximum daily number of volcano-seismic events was 57, reached during the second anomalous period. This seismicity, characterised by focal depth generally lower than 1?km below sea level (b.s.l.) and composed of different kinds of events associated to both resonance and shear failure processes, is related to the shallow dynamics of the hydrothermal system. During the analysed period, very few volcano-tectonic earthquakes took place and tilt recordings showed no sharp or important changes. In light of such observations, the increases in both temperature and volcano-seismic events number were associated to increases in the release of gas from a deep and stable magma body, without magma intrusions within the shallow hydrothermal system. Indeed, a greater release of gas from depth leads to increased fluid circulation, that can promote increases in volcano-seismic events number by both fracturing processes and resonance and vibration in cracks and conduits. The different trends observed in the measured geochemical and geophysical series during the anomalous periods can be due to either time changes in the medium permeability or a changing speed of gas release from a deep magma body. Finally, all the observed variations, together with the changing temporal distribution of the different seismic event kinds, suggest that the hydrothermal system at Vulcano can be considered unsteady and dynamic.  相似文献   

13.
An assessment of water quality measurements during a spring flood in the Elbe River is presented. Daily samples were taken at a site in the middle Elbe, which is part of the network of the International Commission for the Protection of the Elbe River (IKSE/MKOL). Cluster analysis (CA), principal components analysis (PCA), and source apportionment (APCS apportioning) were used to assess the flood‐dependent matter transport. As a result, three main components could be extracted as important to the matter transport in the Elbe River basin during flood events: (i) re‐suspended contaminated sediments, which led to temporarily increased concentrations of suspended matter and of most of the investigated heavy metals; (ii) water discharge related concentrations of pedogenic dissolved organic matter (DOM) as well as preliminary diluted concentrations of uranium and chloride, parameters with stable pollution background in the river basin; and (iii) abandoned mines, i.e., their dewatering systems, with particular influence on nickel, manganese, and zinc concentrations.  相似文献   

14.
Berezina  N. A. 《Water Resources》2000,27(6):654-662
Water quality and the levels of pollution in biological communities of the Kotorosl' River and its major tributaries (the Sara, Lakhost', Mogza, and Pakhma rivers) are estimated by using a considerable body of hydrobiological characteristics (the Pantle–Buck saprobity index and its modifications by Rotshain and the indices of species diversity developed by Shannon; Balushkina; Woodiwiss; Parele; Toderash; Goodnight and Whitley; and Carr, Hiltunenn, and Wright) from the data on the seasonal dynamics of macrozoobenthos. An ecological and sanitary classification of water quality that was developed for this type of rivers is presented. Indices based on the characteristics of oligochaetes, as well as on the taxonomic composition of communities and characteristics of the most indicative species, are shown to be the best choice for characterization of organic pollution prevailing in the Kotorosl' River basin.  相似文献   

15.
根据鉴江流域21个观测点鱼类调查所收集的数据,结合历史资料的记录,初步构建基于鱼类生物完整性评价的26个初选指标,并根据指标属性分类进行初筛,对10个通过的候选指标进行分布范围、判别能力和Pearson相关性分析,确定了由总的种类数占期望值的百分比、鲤科鱼类占总种类数的百分比、鳑鲏亚科鱼类占总种类数的百分比、耐受性强鱼类占总种类数的百分比和产漂流性卵鱼类占总种类数的百分比共5个主评指标组成的生物完整性指数体系,并用于鉴江流域部分河段的生态健康评价.结果表明,凌江鱼类完整性相对较好,罗江一般,平定水、袂花江和鉴江干流较差,小东江最差;鉴江流域大多数河段的综合健康状态处于较差状态,需要对鉴江流域进行生态修复以达到相对健康状态.评价结果与河流受人为干扰的实际情况相吻合,研究构建的评价体系可供周边地区使用和借鉴.  相似文献   

16.
利用现场调查资料重组了2010年3月6日庞凌河流域中的一次陷落地震的灾害过程,并结合现有的水文地质资料和地震记录探讨了该次事件的成因。结果表明:该次事件的地下水异常点均位于龙临—头布暗河系统中,个别异常点位于断裂上,断裂内部的岩溶物质相对疏松。地震波的分析结果表明本次地震事件具有陷落地震的特征。地震发生在前,地下水异常发生在后。据此认为,本次事件可能是一次陷落地震,陷落的岩溶不仅造成了地震,还堵塞了地下河,进而造成了地下水异常。  相似文献   

17.
高俊峰  闾国年 《湖泊科学》2005,17(4):305-310
利用 PcRaster 的环境动态模拟语言,基于地图运算和网格之间水流运动的模拟,开发了水文过程模拟模型,选择 太湖流域上游的西苕溪流域进行试验,用实测资料对模拟结果进行了验证,结果表明模型模拟结果与实际是符合的.本 模型可以用于流域的物质迁移、污染物迁移、人类活动的环境影响变化等的模拟.在此水文过程模拟的基础上,只要叠加 网格上的物质产出率,就可以很容易得到子流域出口的物质通量的变化和其在流域上的空间分布,集成各个子流域过程, 就可以得到流域出口断面的物质通量的变化.  相似文献   

18.
准确判断重大自然灾害发生趋势对于防灾减灾意义重大.基于时间对称性理论,本文构建"可公度降噪—对称性趋势判断—信息结构系稳定性检验"研究模式,判断了淮河流域(HRB)洪涝灾害发生趋势.结果表明:(1)通过可公度降噪处理去除了噪声元素,提高了预测的精确性;(2)运用三元可公度、蝴蝶结构图、信息结构系等方法判断,2019年HRB发生洪涝灾害的信号较强,该年发生洪涝灾害的随机性概率为66.7%,不漏报置信水平为57.1%;(3)通过洪涝灾害与太阳黑子活动的相关性分析可知,HRB在太阳黑子活动谷年附近易发生洪涝灾害,进一步提高了预测结果的可信度."可公度降噪—对称性趋势判断—信息结构系稳定性检验"研究模式是对现有时间对称性方法的补充和完善,以期为中国灾害预测起到一定的推动作用.  相似文献   

19.
Water Resources - This study proposed a hybrid pre-processing approach along with a conceptual model to enhance the accuracy of river discharge prediction. In order to achieve this goal, Ensemble...  相似文献   

20.
高俊峰  闾国年 《湖泊科学》2005,17(4):305-310
本实验的目的是提取和纯化铜绿微囊藻(Microcystic aeruginosa var.major)胞外带酸性基团的多糖,为综合利用爆 发的水华提供一定的理论依据.采用 pH 8.0、80℃的热水抽提铜绿微囊藻的胞外多糖.经充分脱蛋白、脱色后用 DEAE- 纤维素(DE-52)作离子交换柱层析,分离出其中不被 DE-52吸附和被吸附的两种组分.取后者上 sephadexG-150柱进 一步分离得到两种分子量不同的酸性多糖(EAPS Ⅰ和 EAPSⅡ),质量比为1.92∶1,经 HPLC 测定 EAPS Ⅰ均分子量为7.01 ×10~4D,EAPSⅡ均分子量为4.21×10~4D.经测定,它们各带有不同含量的酸性基团:EAPS Ⅰ糖醛酸含量为10.74%, SO_4~(2-)含量为44.44μg/mg,EAPSⅡ糖醛酸含量为7.08%,SO_4~(2-)含量为9.08μg/mg.EAPSⅠ单糖组成为:9.6549%D( ) 木糖,19.2522% D-果糖,71.0930%葡萄糖;EAPSⅡ单糖组成为:6.4065%D( )木糖,18.0016%D-果糖,75.5919%葡萄糖.  相似文献   

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