流域水文模型分析研究

介绍了流域水文模型的分类，以及国内外现有水文模型的研究进展，分析了现有水文模型存在的问题，并提出了若干建议。对未来水文模型作了展望，指出了基于RS和GIS的耦舍水文模型是今后研究的方向。     

现有泥沙理论的不足和改进——扩散模型和费克定律适用性的讨论

描写混合物运动可以采用单流体模型、扩散模型和双流体模型，本文简要介绍了这三种模型，并作了比较，指出：单流体模型方程少、求解简单，但解中包含的信息量少；后两种模型包含的信息量相等，由于扩散模型方程组可以双流体模型方程组引入某种近似后推导出来，它的求解比双流体模型方程组简单，但包含一定的误差，本文分析了这种误差与运动介质物性的关系，给出了扩散模型的适用范围，说明了为什么对于气体混合物常用单流体模型或扩散模型，而对于气－固混合物大多采用双流体模型，液－固混合物性质介于上述两种混合物之间，扩散模型对于它基本上适用，但并不完全适用。扩散模型中的扩散速度表达式，常根据费克定律给出，本文指出了费克定律的局限性，并把它与泥沙运动力学目前遇到的困难联系起来，由此说明采用更一般的扩散速度表达式的必要性。     

污灌污染系统整体数学模型

依据污染物的迁移转化途径，建立了模拟预测迁移型污染物变化的整体数学模型，整体模型由表土层模型、下包气带模型、含水层模型组成，表土层模型为黑箱模型，下包气带模型为一维垂向迁移模型，含水层模型为二维平面迁移模型，子模型之间用流量和污染物浓度耦合·在河北省新河县污灌试验区进行的实例应用中，对求解复杂的含水层模型，采用美国IOWA大学教授陈景仁提出的有限分析法求解，经实测资料验证，整体模型是可靠的，并模拟预测了该区在现状污灌状态下，迁移型重金属As、Cr 6和可降解有机物BOD、COD的变化趋势，及其达标年限     

一种适用于灰色预测控制的无偏直接GM（1，1）模型

GM（1，1）模型是灰色预测控制器的重要组成部分，它是有偏差的模型．提出了一个无偏差的模型一无偏直接GM（1，1）模型，结合具体数据将无偏直接GM（1，1）模型和GM（1，1）模型进行了比较，结果表明无偏直接GM（1，1）模型优于GM（1，1）模型．将无偏直接GM（1，1）模型替代GM（1，1）模型应用于灰色预测控制中可望得到较好结果．     

气流模型在水利科研中的应用

本文探讨了气流模型的相似准则，比尺选择，设备仪器及模型加糙方法，气流模型具有尺寸小，试验周期短，成本低的特点，但试验精度较低。文章例举了应用气流模型的几个实例，并与相应的水流模型，数学模型及工程建成后的运行情况进行了对比。     

尚志镇地下水流三维数值模拟

尚志镇位于山前河谷平原区，地下水主要赋存于多层孔隙介质含水系统中，由于受自然地理条件及人为开采的影响。形成了地下水三维流区，文章根据水文地质模型，建立起了地下水的三维流水分运移数学模拟模型。通过模型求解，模型识别与验证，证实了所建模型可靠。     

干旱灾变预测灰色模型的优化研究

本文将灰色ＧＭ（１，１）模型经过中心差分处理，然后构造了旨在确定灰参数的目标规划模型（ＧＰ模型），为灰色模型参数的确定提供了新的途径，弥补了常规灰色模型的不足，使模型的预测趋势及过程更加合理。通过实例验证了新方法的可靠性和实用性。     

黄河河工模型研究回顾与展望

５０年代初，黄科院即将浑水模型律作为主攻方向之一，开始黄河动床模型试验方法的研究，在此期间，与其他单位共同主持完成了三门峡水库淤积及渭河回水发展野外大模型等试验研究工作。经历了曲比尺模型到自然模型方法的探索，６０年代开始，又将重点转向比尺模型方法的研究，提出了适应于曲 的模型相似律，并开展了大量的试验研究，９０年代以业，黄河模型的相似理论、模型沙材料及试验方法等方面均有长足的发展，且趋于完善，完成     

加里宁—米留柯夫型流域地貌汇流模型

本文根据概念性流域地貌汇流模型的一般理论，建立了加里宁－米留柯夫型流域地貌汇流模型、推导了三级、四级和五级流域的瞬时单位线，并分析了模型参数对瞬时单位线的影响，用内罚函数法估计模型参数，通过实例检验，模型似合精度较高。     

SPAC系统中的水热CO2通量与光合作用的综合模型（I）模型建立

本文建立了模拟农田SPAC（Soil-Plant-Atomosphere Contiuum)系统中土壤水分动态，蒸发蒸腾，CO2通量和光合作用的模型，模型包括土壤流水力子模型，根系蒸腾子模型，冠层阻力－光合作用－CO2通量子模型几个组成部分，土壤水流子模型采用土壤水充的连续议程来描述，根系吸水子模型采用了根据Feddes模型改进得模型，蒸发蒸腾子模型采用Shuttleworth-Wallace公式，采用叶片水平的气孔阻力－光合作用模型，并将其扩展到冠层尺度来确定冠层阻力，光合作用速度以及叶敢也下腔的CO2浓度，并进而确定冠层的CO2通量，本模型的特点是尺可能采用简便的处理方法来描述SPAC系统中的水，热，CO2传输过程与光合作用过程，同时各个子模型又具有较强的机理性。     

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.     

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.     

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.     

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.     

Serial discontinuities in a Rocky mountain river. II. Distribution and abundance of trichoptera

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.     

Surveying for Water Resources

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.     

浅谈优化Vray渲染在制作三维场景的应用研究

用Vray三维渲染引擎来渲染三维场景,其质量和速度是由一些影响因素和参数设置决定的,不同的参数和因素,可以得出不同的三维渲染效果.因此,分析、优化三维渲染质量和速度的影响因素,正确、合理的选择参数对提高Vray最后渲染阶段的质量和速度非常重要.     

固结、渗流和沉积控制方程研究

本文从两相流体动力学的守恒方程出发，考虑固相、液相的相对运动，推导了可以考虑场的不均匀性和流体压缩性的统一形式的控制方程，并对方程所基于的物理概念和相互联系进行了必要的分析。通过对方程适当形式的表达，可导出用于大、小变形固结、渗流和沉积的简化方程，显示了在不同领域的三个理论存在一定的统一性。方程推导过程并未对本构关系加以限制，适用范围较广。依据实际问题的要求，作了不同形式的简化。     

四川省及重庆市中型水电站效益分析

该文分析了四川省及重庆市几座中型水电站的调查材料表明：四川省及重庆市中型水电站不仅在川渝主网和地方电网中起着很大的作用，并具有巨大的社会效益，同时还有综合利用效益，说明修建中型水电站的优越性．