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玉溪市水资源地域差异较大,总体比较匮乏,近年来随着社会经济的快速发展,部分河段和湖泊水质不同程度地受到污染,加之前几年连续干旱的发生,导致出现资源型缺水和水质型缺水并存的问题。为解决这些问题,玉溪市水利部门根据实际情况,规划建设了一批江河湖库水系连通工程,实现了跨流域、跨区域调水,通过对玉溪市目前水系连通工程建设推进情况的调查研究,结合当前实际情况进行分析和思考,提出对今后建设此类工程的建议,包括加强规划,以规划为引领;在水网综合管理框架下,充分保障子水网的安全可靠功能;积极筹集前期工作经费,加大江河湖库水系连通工程前期工作推进力度;与乡村振兴战略紧密结合等。 相似文献
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最近,广东省人民政府、广西壮族自治区人民政府联合发文,批准了《九洲江水系水资源保护规划纲要》,标志着九洲江水系水资源保护规划正式进入实施阶段。 九洲江发源于广西陆川县境内,流经广西博白县、广东廉江市后进入北部湾,干流长度162公里,集雨面积3337平方公里,其中广西境内河长55公里,集雨面积1092平方公里。九洲江是我国南方较重要的跨省的独流入海河流,是广东湛江市和广西玉林市沿江各乡镇的重要供水水源。随着社会经济的发展,九洲江沿线用水量、排污量不断增加,河流水体受到不同程度的污染,水资源供需矛盾… 相似文献
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对九洲江流域玉林河段的7个水功能区进行水质监测,以各水功能区的水质管理目标进行达标评价。同时,根据九洲江流域污染物的特征,选取溶解氧、高锰酸盐指数、BOD5、NH3-N、总磷等5个典型水质指标,以综合指数评分法对九洲江流域干流水质进行评价,分析各水功能区的水质现状和污染特征。结果表明,九洲江陆川县城以下河段受到一定污染,主要污染物为NH3-N,污染物来源为养殖和城镇生活废污水。 相似文献
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汉寿县南湖撇洪河是湖南省三大人工撇洪工程之一,励精图治近30年,目前仍是汉寿县水利部门的防洪重点、难点。为了把汛期洪涝灾害减少到最低程度,文章针对现有流域内的河湖历史演变、水情工情变化、水系形态特征、水利工程现状、造成洪灾成因、流域的整治规划从理论到实践进行了认真的分析研究,提出了"汛期早做准备、汛中科学调度、汛后规划治理、江河湖库连通"的南湖撇洪河流域防洪与治理应对策略。 相似文献
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《中国水能及电气化》2020,(8)
乌石拦河闸引水工程是韩江-榕江-练江水系连通工程的子工程之一,是改善练江流域水环境污染、水生态破坏等问题的水系连通工程。韩江-榕江-练江水系连通乌石拦河闸引水工程中夏地分干渠渠道的改造及整治中,设计保留现有渠道,仅对其清淤、扩容等进行优化设计,以满足对练江流域生态补水的需要,同时改善了自然环境,可为以后类似设计提供参考。 相似文献
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在自然演变和人工干预双重影响下,河湖水系的发育程度和连通效果在不断变化,进而影响到流域水资源的合理开发利用。本文以淮河流域作为研究对象,从数字高程模型中提取了全流域水系结构图,并根据其他资料对结果进行修正;基于当地人工水系建设背景,运用分形理论计算了全流域13个水资源三级分区有、无人工水系情况下的水系分形盒维数;基于河道闸坝工程建设背景,运用图论方法计算了全流域13个水资源分区有、无闸坝工程情况下的水系连通度;最后,采用统计学方法研究了淮河水系盒维数指标与水系连通度指标之间的联系。结果显示,剔除人工水系后的各分区水系盒维数有不同程度的下降,且下降程度与区域水系个数、面积一定程度上成正比例关系;考虑有无人工水系、闸坝工程影响的各分区水系连通度,有的增大,有的减小;水系盒维数与连通度间大体上呈现正相关的趋势关系。研究成果可为有关部门开展淮河流域水系建设工作提供理论支撑,为摸清自然规律和人类活动对水系形态结构、发育情况和连通性的影响提供技术支持。 相似文献
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The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L?1, the median total phosphorus was 0.29 mg L?1 and the median total nitrogen was 1.56 mg L?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd. 相似文献
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Carbon dioxide (CO2) and methane (CH4) diffusive emissions were measured during two field surveys in Queensland and Tasmania, Australia, using the floating chamber method. Bubbling and degassing emissions in 2010 were estimated in Koombooloomba Dam reservoir using only inverted funnels and gas concentrations, respectively. A total of 14 reservoirs and 16 rivers and lakes were sampled from 2006 to 2010. Spatial variation was substantial within each water body, as well as between them. The main drivers of diffusive emission variation were physiographic region and climate, with a clear demarcation being observed between diffusive emissions from tropical Queensland and temperate Tasmania, and between the humid West Coast Range (Tasmania) and dry Central Plateau (Tasmania). Higher CO2 and CH4 diffusive emissions were observed during the dry season, when long water residence times would promote organic matter degradation. Estimated total gross emissions, including diffusive, bubbling and degassing emissions, for Koombooloomba Dam reservoir were about 1.5 × 106 t CO2eq km2 per year, or 24 × 106 t CO2eq per year. This corresponds to a plant emission factor of 3.18 kg CO2eq MWh?1. Using an estimate of terrestrial emissions derived from literature data for the Tully River catchment area, rough estimated net emissions from the catchment area are about 44 kt CO2eq per year, or 5.83 kg CO2eq MWh?1, which is in the lower range of the studied reservoirs. 相似文献
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River regulation in the headwaters and middle reaches of the Gunnison River, Colorado, significantly altered distributions and abundances of Trichoptera fauna. Twenty-five species were collected from mainstream samples, with the greatest species richness occurring at an unregulated, rhithron segment above the central reach dams. At sites immediately below the three hypolimnial-release dams and a reregulation dam, species richness was reduced 35–90 per cent and abundance > 95 per cent. Net-spinning caddisflies were the dominant trichopterans at unregulated sites; Arctopsyche grandis in the upper reaches (218 organisms, 586 mg dry mass m?2) and Hydropsyche cockerelli, H. occidentalis and Cheumatopsyche pettiti in the lower river (9041 total organisms, 6621 mg m?2), downstream from the last dam. The observed distributional pattern of low trichopteran densities in dam tailwaters and high hydropsychid densities at sites 60–80 km below the central reach dams is a classic expression of continuum resets and adjustments in response to stream regulation as predicted by the Serial Discontinuity Concept. 相似文献
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Peter M. Gibbs 《国际水》2013,38(4):547-557
Abstract A professional Land Surveyor (Geomatician) describes the Hydrogeologists' survey requirements of a major water resources assessment for the government of The Sultanate of Oman (1992 to 1996). The need for objective specifications is stated. Specialist terms like geoid, spheroid, Mean Sea Level are explained and how to relate spheroidal levels to the geoid. Methods like traditional survey, satellite survey, and photogrammetry are introduced. The paper encourages coordinated working for the benefit of water resource assessment and recommends employment of the professional land surveyor for major studies. 相似文献
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Suleyman A. Muyibi Abdul Raufu Ambali Garoot Suleiman Eissa 《Water Resources Management》2008,22(4):485-508
The paper examines the impact of development activities on water pollution in Malaysia. Hence, the main objective of this
paper is not just to examine the trends of development-induced water pollution around the region of the country but to know
where the problems are and the policy measures taken by the government. It evaluates the probable causative relationship between
problems introduced due to technology employed in water pollution control and governmental policy measures. It examines the
relationship between development indicators as sources of pollution and polluted rivers over a period of 12 years. The findings
of the paper have shown that despite the policy enforcement actions against the identified sources of water pollution, all
the three development indicators (chosen based on those identified sources) still accounted for high percentage of river pollution
in Malaysia. The findings of the paper were used to identify the central fact of the location of the problem. Some crucial
conclusions of where the problems likely to be, as reflected in the findings, are: (a) the issue of interactive-effects between
pollutants that many policy-makers are not aware of. This is when policy measures concentrate only on one source of water
pollution; (b) the enforcement strength and/or effectiveness of policy measures themselves; (c) financial constraints to invest
in appropriate technology especially sewerage systems for controlling human source of water pollution in the country; as well
as those confronting small polluting industries (d) finally, lack of cooperation between government and private business firms
to comply with regulatory policies for water pollution control. 相似文献
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Intangible Flood Damage Quantification 总被引:3,自引:0,他引:3
Flooding is a natural disaster that may cause tremendous tangibleand intangible damage to the national economy. The tangible damage assessment, i.e. the monetary value of all direct and indirect physical damages, has already been studied, whileintangible damages have not yet been taken into account. Thisarticle, therefore, is the first systematic attempt to assess bothtangible and intangible damages. The new proposed Anxiety-Productivity and Income Interrelationgship Approach (API) has been developed to quantify the intangible damage in monetary terms. The Bangkok area has been selected as the research area because several severe flood events have occurredthere over the last two decades. The 1983 Bangkok flood caused 6600 million baht in damage, according to estimates by the National Statistical Office (NSO). This article examines the totalflood damage (including the intangible damage) at different flood magnitudes. Case studies with and without flood mitigation projects are studied and compared. Furthermore, thisarticle also discusses the improvements over the conventional approach offered by the new API methodology. 相似文献
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Floodplains are generally considered to be important locations for nutrient retention or inorganic‐to‐organic nutrient conversions in riverine ecosystems. However, little is known about nutrient processing in short‐hydroperiod floodplains or seasonal variation in floodplain nutrient retention. Therefore, we quantified the net uptake, release or transformation of nitrogen (N), phosphorus (P) and suspended sediment species during brief periods (1–2 days) of overbank flooding through a 250‐m floodplain flowpath on the fourth‐order Mattawoman Creek, Maryland U.S.A. Sampling occurred during a winter, two spring and a summer flood in this largely forested watershed with low nutrient and sediment loading. Concentrations of NO increased significantly in surface water flowing over the floodplain in three of the four floods, suggesting the floodplain was a source of NO. The upper portion of the floodplain flowpath consistently exported NH, most likely due to the hyporheic flushing of floodplain soil NH, which was then likely nitrified to NO in floodwaters. The floodplain was a sink for particulate organic P (POP) during two floods and particulate organic N and inorganic suspended sediment (ISS) during one flood. Large releases of all dissolved inorganic N and P species occurred following a snowmelt and subsequent cold winter flood. Although there was little consistency in most patterns of nutrient processing among the different floods, this floodplain, characterized by brief inundation, low residence time and low nutrient loading, behaved oppositely from the conceptual model for most floodplains in that it generally exported inorganic nutrients and imported organic nutrients. Published in 2007 by John Wiley & Sons, Ltd. 相似文献
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N. N. Man'kina B. S. Fedoseev A. V. Kirilina Yu. A. Voropaev 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2004,38(2):95-98
Conditions of the process of steam-water-oxygen cleaning, passivation, and conservation (SWOC, P, and C) of internal heating surfaces of the boiler and the high-pressure feed heater (HPFH) piping over the steam side are presented. The process produces partial cleaning of the internal heating surfaces from scale and yields a corrosion-resistant protective film that hinders corrosion processes both in the operation of the boiler and in the idle period. 相似文献
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基于虚拟裂缝模型,针对钢筋混凝土试件在三点弯曲作用下开裂截面的受力特征,在合理假定的前提下,给出了一种计算钢筋混凝土三点弯曲梁的失稳断裂韧度的解析方法。然后,应用该方法计算了初始缝高比α0(初始裂缝长度与试件高度的比值)分别为0.2,0.3,0.4,0.5的三点弯曲试件的最大荷载和临界有效裂缝长度,进而求得了钢筋混凝土三点弯曲梁的失稳断裂韧度。通过对计算结果与试验数据的误差分析,发现失稳断裂韧度最大误差为4.915%,说明这种方法可以较为准确地预测三点弯曲梁的失稳断裂韧度。在此基础上研究了初始缝高比α0对失稳断裂韧度的影响,发现失稳断裂韧度基本上不随α0变化,失稳断裂韧度可以作为材料常数,应用于裂缝扩展状态的判断。 相似文献