山西省水-能源-粮食系统耦合协调时空变化特征研究

为探究山西省水-能源-粮食(W-E-F)系统耦合协调程度的时空变化特征,构建W-E-F系统评价指标体系,采用综合评价指数和耦合协调模型,测算全省及各地市2008-2017年W-E-F系统发展水平及其耦合协调程度,并分析其时空变动特征。结果表明:9年间全省W-E-F系统耦合协调度从0. 55上升到0. 83,总体达到良好协调水平。但各子系统发展特征不同,粮食子系统发展水平较高,表现稳定,水资源子系统发展滞后且稳定性较差。系统协调水平和各子系统的发展水平均存在显著且逐渐扩大的空间差异,2017年初级协调区和中级协调区占比分别为45%和55%。太原、忻州和晋中3市协调水平较高,协调水平较低的朔州和运城主要受能源和水资源子系统的制约;各子系统空间差异大小为能源>粮食>水资源,W-E-F各子系统发展水平最低的地区分别是运城、朔州、阳泉。大多数地区面临W-E-F系统内部发展日益失衡的问题,各子系统间存在突出的矛盾,主要表现为粮食和能源子系统与水资源子系统之间的压力和制约效应。最后提出促进山西省W-E-F系统协调发展的措施。     

水资源-能源-粮食-生态系统耦合协调及驱动力分析

为加深对我国水资源、能源、粮食、生态系统协同演变趋势的认识,构建水资源-能源-粮食-生态多维系统指标体系,运用耦合协调度模型对我国2005—2020年水资源-能源-粮食-生态系统耦合协调度进行评价,并采用多因素归因分析法进行驱动力分析。结果表明：我国水资源-能源-粮食-生态系统耦合协调度从2005年的0.55增长到2020年的0.84,各地区耦合协调度从勉强协调发展水平过渡到中级协调发展水平,各子系统对耦合协调度上升的驱动分别经历了由粮食子系统到生态子系统再到水资源子系统主导的过程;能源子系统的贡献率虽然比较小,但是未来可能是各地区提升水资源-能源-粮食-生态系统多维系统协调发展水平的突破口。     

黄河流域水-能源-环境系统动态耦合协调发展研究

为研究水、能源与环境子系统之间的耦合协调关系及动态演变特征,基于2010—2019年黄河流域9个省(区)的面板数据,建立水-能源-环境系统的耦合协调评价指标体系,通过熵权法、耦合协调模型定量分析水-能源-环境系统与子系统之间的耦合协调发展水平。结果表明：在研究期内,黄河流域水-能源-环境系统一直处于高水平耦合状态,耦合协调度在波动中上升,经历初级、中级协调两个阶段并有向良好协调类型演进的趋势,但三者之间的耦合协调关系仍存在较大上升空间;水资源子系统起主导作用,并且2016年之后的发展速度明显快于能源子系统和环境子系统。建议针对当地情况,通过跨部门合作提升滞后子系统的发展水平,实现资源子系统与环境子系统的持续协调发展。     

山东省水-能源-粮食系统耦合协调关系变化研究

山东省地处黄河下游,是粮食生产和能源消耗大省,水资源供需矛盾突出,为实现区域资源可持续发展,采用耦合协调评价模型,分析山东省2000—2020年水-能源-粮食系统耦合协调发展变化特征。结果表明：山东省水-能源-粮食系统整体发展趋势较为稳定,处于初级协调阶段;各子系统间离散程度相对较低、相互影响程度高,大多数年份水-能源-粮食系统处于初级协调阶段;干旱导致水资源短缺、能源供需矛盾等问题,对系统耦合协调程度影响较大,提升抗旱减灾和能源保障能力可促进山东省水-能源-粮食系统协调可持续发展。     

陕西省水资源与能源系统耦合协调发展分析

水资源和能源系统间存在着复杂的关联关系。能源的发展需要大量的水资源,污水净化和水资源的开采、调度也需要大量的能源,日益增加的水资源和能源需求让陕西省经济发展面临着严重的瓶颈。文章在探索水资源与能源系统相互作用机理的基础上,定义了耦合协调度的概念,以定量描述水资源系统与能源系统之间相互作用、协调发展的程度。通过构建耦合协调度模型,建立水资源子系统和能源子系统指标体系,由实证分析得到两系统综合评价指数,水资源与能源综合评价指数呈现逐渐上升态势,且水资源子系统和能源子系统基本一致发展。水资源与能源系统耦合度在2009年出现了较为明显的下降,其余各年基本保持稳定水平,均处在耦合度大于0. 95的高水平耦合状态。水资源与能源系统耦合协调度在2005—2010年呈现波动状态,但整体呈现缓慢上升态势。两系统间相互作用较强,协同发展状况由中等协调发展逐渐转变为良好协调发展。     

水资源-经济-社会复合系统协调度研究

为研究水资源利用程度对地区综合发展水平的影响及支撑能力,将水资源作为子系统与社会系统及经济系统相结合,综合评价复合系统的协调度水平,并分析其发展状态。在对黑龙江省水资源–经济–社会复合系统协调度评价的过程中,运用主成分分析法对指标进行筛选,并以模糊综合评价法(FAHP)作为赋权方法,探求了黑龙江省水资源–经济–社会复合系统发展的协调程度,多年来各子系统的协调发展变化,以及不同地级市之间水资源系统、经济系统及社会系统的综合发展差异化水平。结果表明:黑龙江省水资源–经济–社会复合系统中以经济子系统发展为主,水资源系统发展呈现不稳定状态;不同地级市之间3个子系统的综合发展水平具有明显差异。     

京津冀地区水-能源-粮食系统协同发展评价

为保障水-能源-粮食系统协同发展,以协同学理论为基础,构建协同度评价模型。从水资源系统、能源系统、粮食系统3个层面选取25个指标构建京津冀地区水-能源-粮食系统协同发展评价模型,对京津冀地区协同发展水平进行评价。结果表明,京津冀地区水-能源-粮食系统协同度整体上呈现上升趋势,但京津冀各地协同程度存在一定差异;2011—2016年京津冀协同度变化无规律,处于较低的水平,2017—2020年协同度呈明显上升趋势。     

区域水-能源-粮食耦合协调演化特征研究——以江苏省为例

随着我国淡水资源减少,能源需求增加,粮食供给的不确定性愈加严重。以江苏省为研究对象,通过构建水资源-能源-粮食(W-E-F)系统耦合协调评价指标体系,采用熵值法对各子系统指标赋权,利用耦合协调模型进行对协调发展水平进行定量评价,并基于灰色GM(1.1)模型预测未来5年的耦合协调度。结果表明:江苏省2000-2015年W-E-F系统的综合评价指数整体上随时间呈上升趋势;耦合度基本保持高水平耦合;耦合协调度呈倒"U"型曲线,经历了初级协调、勉强协调、中级协调3个阶段,并在未来5年内向良好协调类过渡。但水资源与能源的发展水平仍滞后于粮食,故提高水与能源的利用效率,以促进区域的可持续发展。     

中国水—能源—粮食纽带系统安全水平与全要素生产率时空耦合协调关系分析

为研究中国资源系统与经济系统耦合协调发展状况,通过构建水-能源-粮食纽带系统安全评价指标体系,应用TOPSIS模型、DEA-Malmquist指数和耦合协调度模型,对中国30个省(自治区、直辖市)(不包括港澳台及西藏)水-能源-粮食纽带系统安全水平与全要素生产率进行了测算,从时间和空间的角度分析了二者耦合协调关系。结果表明：中国水-能源-粮食纽带系统安全水平呈“双极分布”的空间格局,整体安全水平逐年提升,粮食子系统安全水平最高,水资源子系统安全水平最低;2005—2019年中国全要素生产率呈波动上升态势,水-能源-粮食纽带系统与全要素生产率耦合协调时空格局差异显著,耦合协调度呈现上升趋势,空间格局由南至北呈现出“高—低—高”的空间分布特征,时间维度上耦合协调呈现向高水平耦合阶段演进的趋势。     

吉林省水-能源-粮食系统耦合协调度评价研究

【目的】水、能源、粮食是保障人类生存与福祉的重要物质基础,研究吉林省水-能源-粮食系统的耦合协调发展状况,以促进吉林省水、能源、粮食的可持续发展。【方法】以吉林省为研究区,建立水-能源-粮食(W-E-F)系统综合发展评价指标体系,利用耦合协调度模型定量评价2003—2020年W-E-F系统耦合协调状况,运用GM(1,1)预测2021—2030年耦合协调度。【结果】结果表明：吉林省W-E-F系统综合发展评价指数呈现波动上升趋势,由0.29增长至0.67,其中水资源系统发展指数对综合系统发展指数影响大;耦合度在0.88～0.99范围内,处于高水平耦合阶段,耦合协调关系由勉强失衡逐步发展到中级协调水平,表现出向好的趋势,预测2030年将达到高级协调,最后为促进吉林省W-E-F系统耦合协调发展提出了相关建议。【结论】耦合协调度模型能够有效定量评价吉林省水-能源-粮食系统的协调发展状况,为吉林省水-能源-粮食系统协调发展提供科学参考。     

Call for Papers

正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc.     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

库水波动下库岸边坡地下水浸润线解析解及误差分析

解析法是库岸边坡地下水浸润线计算中便于实际应用的方法,但该方法须基于若干假定并对潜水运动基本方程线性化后才能求解。针对各假定和线性化过程建立不同的地下水渗流数学模型,用解析法和有限元法解答上述数学模型,分析各误差大小及其规律。结果表明：库岸垂直处理带来的误差要小于方程线性化处理和不考虑非饱和渗流带来的误差,而且它们都随渗透系数变大而减小;在三峡库区库水调度情况下,假定库水位等速变化带来的误差对大多岸坡而言可以忽略;计算库岸边坡地下水浸润线时,解析法只适用于水位变化幅度相比含水层厚度较小,且几何边界规则、岩土结构简单、岩土体渗透性较好时的情况。     

Changes in Summer Irrigated Crop Area and Water Use in Southeastern Turkey from 1993 to 2002: Implications for Current and Future Water Resources

Changes in summer irrigated cropland acreage and related water use are estimated from satellite remote sensing and ancillary data in semi-arid Southeastern Turkey where traditionally dry agricultural lands are being rapidly transformed into irrigated fields with the help of water from the Euphrates-Tigris Rivers. An image classification methodology based on thresholding of Landsat NDVI images from the peak summer period reveals that the total area of summer irrigated crops has increased three-fold (from 35,000 ha to over 100,000) in the Harran Plain between 1993 and 2002. Coupled analysis of annual irrigated crop area from remote sensing and potential evapotranspiration based estimates of irrigation water requirements for cotton indicate a corresponding increase in agricultural water use from about 370 million cubic meters to over one billion cubic meters, a volume in accordance with the state estimates. These estimates have important implications for understanding the rapid changes in current agricultural withdrawals in Southeastern Turkey and form a quantitative basis for exploring the changes in future water demands in the region. For example, expansion of irrigated lands have led to a steady decrease in potential evaporation due to increased roughness and decreased humidity deficit in the Harran Plain. Assuming that the changes in future evaporation conditions will be of similar nature, water use for irrigation is expected to decrease over 40 percent in future irrigation sites. Incorporating this decrease in overall planning of the irrigation projects currently under construction should lead to improved management, and by extension, sustainability of water resources in the region.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

SPATIAL AND TEMPORAL WATER QUALITY VARIABILITY IN AQUATIC HABITATS OF A CULTIVATED FLOODPLAIN

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.     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.     

Spatio‐temporal variation of gross CO2 and CH4 diffusive emissions from Australian reservoirs and natural aquatic ecosystems,and estimation of net reservoir emissions

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.