Applied Mechanics and Materials Vols. 641-642

Abstract: In order to investigate the water security situation in typical rural areas of Shandong province, the index system of water security assessment were estasblished based on full understanding of water security as well as combination between actual situation of Shandong province and the definition rural water security. With six county-level city of Shandong province as examples for water security evaluation, each index weigh was calculated by entropy method according to the fuzzy comprehensive evaluation method .It was showed that the water security rank from bad to good was shouguang city, ju county, qingyun county, wendeng city, feicheng city and linqu county. The evaluation results was in keeping with the actual condition of water resources, which shows that this system is applicable on rural water security evaluation.

Abstract: Based on adequate consideration of status of water resources utilization and socio-economic development in the Shanxi Provinces, the AHP method was used to calculate the weights of each index and the fuzzy comprehensive evaluation of water resource carrying capacity in the Shanxi Province was carried out from 2006 to 2011. The evaluation results indicated that the overall level of the water resources carrying capacity in Shanxi Province was contained in critical state, however, a steady rise.

Abstract: With rapid development of society and economy, the issue of water shortage has presently been more and more serious in China. Optimal water and land resources allocation, involving many aspects such as society, economy, ecology etc., is a rational approach to solve this problem. In this study, a substantially improved model, i.e., multi-objective optimal allocation, is established for coordinating the usage of water and land resources. The model was developed on the basis of Immune Genetic Algorithms (IGA), and it mainly includes three objectives and seven constraints. The results of case study show that there is no water shortage in the predicting year of 2020 in Dongtai City, Jiangsu Province by using the optimal allocation of water and land resources. The new optimal allocation proposed in this study has a positive influence to promote the economic and social harmonious development and the natural environment protection for coastal areas of China.

Abstract: Traditional reservoir operation ignores ecological demands of rivers. This would probably lead to degradation of river ecosystem. In order to alleviate the influence of reservoirs on river ecosystem, multi-objective reservoir ecological operation was proposed from perspective of maintaining the river ecosystem health. Multi-objective mathematical model of multi-reservoir ecological operation was established. A multi-objective particle swarm optimization (MOPSO) algorithm was introduced to generate a set of Pareto-optimal solutions. In addition, to facilitate easy implementation for the reservoir operator, a simple but effective decision-making method was presented to choose the desired alternative from a set of Pareto-optimal solutions. Finally, the proposed approach was applied to the ecological operation of the reservoirs at the main stream of Xiuhe river in Poyang Lake basin in China. The results show that the proposed approach is able to offer many alternative policies for the water resources managers, and it is a viable alternative to solve multi-objective water resources and hydrology problems.

Abstract: The non-uniform sediment input has played a significant role in the bed evolution in the middle and lower Yangtze River, which indirectly influences the amount of the sediment transported into the East China Sea every year. However, it has been dramatically changed by the climate change, especially the human activities in the upper Yangtze River, not only the amount, but also the grading. The average annual sediment load has reached to 402.6 million tons since 1960s, while showing a decreasing and refining trend mostly influenced by the human activities, such as soil and water conservation, and large hydropower projects. The most direct consequence of these changes was to cause severe erosion in the middle and lower Yangtze River, further to bring about fluvial regime adjustment. In this article, a series of daily and annual averaged sediment transport data since 1960’ were collected and analyzed to find the impacts of the significant human activities on the non-sediment input of the middle Yangtze River, and then its variation tendency was predicted, affected by the existed large hydropower projects and to be build ones in the upper Yangtze river. The result shows that the non-uniform sediment input of the middle Yangtze River was slightly reduced by the operation of Gezhouba Project and the up and middle Yangtze River water and soil conservation prevention and control projects, and further less after the impoundment of Three Gorges Reservoir, meanwhile its grading has been getting finer and finer. In future, along with the normal operation of the Three Gorges Reservoir and the built of the cascade reservoirs in the upper main stream and tributaries of the Yangtze River, it will be continuously reduced and refined.

Abstract: Water allocation is a very complex problem, involving social, economic, environmental, and political factors. Consequently, it is a multi-objective decision-making problem. This paper presents a multi-objective model for the optimal allocation on multisource water for multiuser under sufficiently considering the harmonious development among economy, society and environment. A multi-objective particle swarm optimization (MOPSO) algorithm is employed to generate a set of Pareto-optimal solutions. At the same time, to facilitate easy implementation for the water allocation operator, information entropy theory is adopted to sort the decision results according to the magnitude of the superiority degrees. As a case study the proposed approach has been applied to the reasonable allocation of water supply and demand in the water-receiving areas of the South-to-North Water Transfer Project in China, in which the maximal benefit of economy, society and environment was regarded as the multi-objectives. The results show that the proposed approach is able to offer the quantifiable benefits or costs among different objectives for the water managers, and is highly professional in making decisions for allocating water among use sectors and different areas.

Abstract: The artical is based on the investigation of the basis of the status quo of Zhuxianzhuang and Luling coal mining subsidence area in Anhui province Suzhou city(hereinafter referred to as the "Zhu Lu subsidence area"), a preliminary analysis of the dynamic change trend of detention space in Zhu Lu subsidence area, and based on the hysteresis storage conditions of subsidence area, use the flood routing model to simulate the hysteresis effect of storage at different subsidence scenarios of different frequency flood. Finally, using the experience type channel evolution model and peak delay routing model further revealed storage effect on flood process of Zhu Lu subsidence area.

Abstract: Currently, the development of flood control system of Nanjing City has been entering a new critical phase, facing some great challenging problems that never experienced before. To meet these challenges, this research initially reviewed the developing process of flood control system of Nanjing City after China's reform and opening up. Based on the analysis of current flood control situation, four major challenge of was summarized. To solve these problems, this research provided some productive suggestions for future development of flood control system of Nanjing City from six perspectives, namely principle of flood control, layout of flood control system, drainage system improvement, flood management, technology application and supporting measures.

Abstract: Nansi lake is composed by Nanyang, zhaoyang, dushan and weishan through natural open channel. The characteristics of 4 lake are great disparity, and inflow each other. Because of the complicated influence of transmitting water by open channel, observation error of reservoir level and calculation error of backwater storage, many flood forecast projects established in the past did not come to applied level. This paper develops the conflux forecast project of anti-error zoning based on analyzing characteristics of error generation of Nansi lake flood, and adopts real-time adjustment technique. It basically avoids the calculating error problem, the qualified rate of flood peak, the qualified rate of time to peak of Nansi lake flood forecast project come to 89.3%,100%,91.3%.

Abstract: According to researches on mechanism and concept of off-stream ecological water demand, off-stream ecological water demand of Fu River Basin is consist of ecological water demand for soil and water conservation and for urban public green space, considering the current situation and planning objectives of off-stream ecological water demand of Fu River Basin. Directly calculation method is employed in this study. Choosing 2005 as the current year in this study, indicators of public green space and soil erosion data are obtained. Then the ecological water demand of urban public green space in Fuzhou City is determined as 0.438×10⁸m³ and the water demand for off-stream soil and water conservation in Fu River Basin is determined as 0.3159×10⁸m³ in virtue of quota method. The off-stream ecological water demand in the Basin (2005 as the current year) is about 0.359×10⁸m³. The determination of the off-stream ecological water demand in the basin provide a scientific basis on taking a variety of water-saving measures, improving the recovery rate of sewage treatment and increasing the off-stream ecological water consumption. Results of this study will make the ecological environment of this area to achieve a healthy state, and shall greatly improve regional water resources and water environmental situation.