芦苞涌、西南涌分洪对下游三角洲水环境影响及对策研究

主要讨论在现阶段环境条件下,北江大堤加固达标及芦苞涌、西南涌整治后,将可按设计分洪流量共2300m3/8分洪,对下游三角洲网河区的洪水过程及水质过程等水环境影响进行了分析,并提出分洪期水污染防治对策.

Purification Effects of Aquatic Vegetations on Lake Wetland Water Environment and Analysis of the Influencing Factors in Hongze Lake

[Objective] To study the purification effect of plant community on wetland water environment in Hongze Lake, and to provide references to the ecological restoration of this area. [Methed] The typical lakeside zone of Hongze Lake Wetland National Nature Reserve was taken as the study area. Through the field survey based on environmental characteristics of aquatic areas and non-aquatic areas, combined with laboratory test, the content changes of nutrients （N and P）, COD （chemical oxygen demand） and SD （transparency） levels in the water body of lake wetland were measured; the purification effect of the lake wetland ecosystem in the growth process of aquatic vegetation was quantitatively analyzed, and possible influ- encing factors were discussed. [Result] Aquatic vegetation could remove the TN, TP, COD, Chla in wetland water environment and had obvious effects on the changes of SD content. Competition between aquatic plants can inhibit the growth of algae and relieve the eutrophication of water body. [Conclusion] This study provided theoretical basis for ecological restoration and enhancement of self-purification capability in the lakeside zone of Hongze Lake.

Current Situation and Prevention of Soil Erosion from Construction of West-East Natural Gas Transmission (Ningxia-Shaanxi Section)

In the research, problems and damages of soil erosions in West -East Natural Gas Transmission were analyzed; the reasons were summarized and the characteristics of soil erosion were researched in order to explore principles of pipeline prevention and seek countermeasures.

Sensitivity Analysis of Thermal Equilibrium Parameters of MIKE 11 Model:A Case Study of Wuxikou Reservoir in Jiangxi Province of China

Sensitivity analysis of thermal equilibrium parameters in the reservoir module of MIKE 11 model was conducted for the Wuxikou Reservoir in Jiangxi Province of China in order to apply the module to the environmental impact assessment to accurately predict water temperature of reservoirs.Results showed that radiation parameter A and evaporation-first parameter were much more sensitive than other parameters.The values of the radiation parameter A ranged from 0.10 to 0.34.The values of evaporation-first parameter varied from 0 to 10.The sensitivity of solar absorption parameters was less than that of evaporation parameter,of which light attenuation values ranged from 0.5 to 0.7,and this parameter would not impact model results if it was more than 2.Constants in Beer's law ranged from 0.2 to 0.7.Radiation parameter B was not more sensitive than evaporation parameter and its reasonable range was higher than 0.48.The fitting curves showed consistent changing tendency for these parameters within the reasonable ranges.Additionally,all the thermal equilibrium parameters had much more important effects on surface water temperature than deep water temperature.Moreover,if no observed data could be obtained,the local empirical value would be used to input to the MIKE 11 model to simulate the changes in the discharged outflow-water temperature qualitatively.

Substituted plan analysis in the environmental impact assessment of Yongchuan wastewater treatment project

Substituted plan in the environmental impact assessment (EIA) mainly means the treatment technology and the substituted site of plant, and it also includes the many kinds of environment protection measures. This paper will make detailed analysis on the treatment technology, the substituted site of plant, the purpose of discharged water and the dispose of sludge in the Yongchuan wastewater treatment project.

Water coning mechanism in Tarim fractured sandstone gas reservoirs

The problem of water coning into the Tarim fractured sandstone gas reservoirs becomes one of the major concerns in terms of productivity, increased operating costs and environmental effects. Water coning is a phenomenon caused by the imbalance between gravity and viscous forces around the completion interval. There are several controllable and uncontrollable parameters influencing this problem. In order to simulate the key parameters affecting the water coning phenomenon, a model was developed to represent a single well with an underlying aquifer using the fractured sandstone gas reservoir data of the A-Well in Dina gas fields.The parametric study was performed by varying six properties individually over a representative range. The results show that matrix permeability, well penetration(especially fracture permeability), vertical-to-horizontal permeability ratio, aquifer size and gas production rate have considerable effect on water coning in the fractured gas reservoirs. Thus, investigation of the effective parameters is necessary to understand the mechanism of water coning phenomenon. Simulation of the problem helps to optimize the conditions in which the breakthrough of water coning is delayed.

IMPACT EVALUATION OF HAIZUKA DAM ON ITS UP STREAM A CASE STUDY IN HIROSHIMA PREFECTURE, JAPAN

Japan ranks fifth in the world for the number of large dams. Environmental impacts of large dams are known, such as enormous losses of water or disruption of fish spawning, however, impacts of the dams on their up streams are functions of topography of the up stream. Haizuka Dam is located in Hiroshima Prefecture, Japan and its implementation will start in 2006. This large dam influences its up stream through dam making activities, which occurs in order and with different spatial presences that were categorized into chronological and spatial impacts. In this case study, spatial impacts were further divided into horizontal and vertical ones. The horizontal impacts were identified as new roads, diversion tunnel, dam lake, and submerged cultivated land, while vertical impacts were recognized as submerged historical monuments, slope protections, dam body, and deforested area in the reservoir. There were convergences of spatial and temporal impacts, however, the extent of the impacts was limited to the lake boundary.

Study on environmental impact of coal mining subsided water area in Huainan mining area

The subsided water areas with different times of subsidence are chosen to monitor the physicochemical indexes and heavy metal elements. The results indicate that subsided water areas are polluted in different degree. Some physicochemical indexes of subsided water areas are increased with the development of the subsidence and are changed with the changing of the season. The concentration of As, Cd, Cu, Pb, Se, Zn of subsided water areas is less than national fishery, and surface water quality standards of China , except Hg. And the quality of subsided water hasn＇t been polluted by heavy metal seriously. Analyzing and appraising the quality of the subsided water can give a reasonable data as basis in using the subsided water resource.

Environmental impacts assessment for hydropower development planning in China

This article briefly introduced China’s law framework and technical standards related to environmental impacts assessment(EIA) for hydropower development, and the EIA developing process for hydropower development planning. Authors summarized the working experiences about hydropower development planning EIA done in the recent years in China, discussed the considerations and methods of hydropower development planning EIA, and put forward the index system for hydropower development planning EIA initially.

Effect of Water Resources Allocation on Groundwater Environment and Soil Salinity Accumulation under Climate Change

The combined surface and groundwater allocation practice by wells and canals had contributed to the safety of groundwater environment and agriculture sustainable production. The typical area in the People＇s Victory Canal irrigation district was taken as a case, drawing together the irrigation district agriculture water consumption and precipitation from 1954 to 2014 in the People＇s Victory Canal irrigation district, ratios of surface to groundwater irrigation amount, dynamic of groundwater depth and hydrochemical characteristic of groundwater from 2008 to 2014 in the research area, the relationship between groundwater depth and ratio of surface to groundwater irrigation amount was analyzed, in order to ascertain the influence of precipitation on ratios of surface to groundwater irrigation amount and its effect on soil and groundwater environment. The results indicated that positive correlation between the ratios of surface to groundwater irrigation amount and annual precipitation was appeared, affected by climate change, average irrigation amount from surface in the recent 5 years was 2.90 x 108 cubic meters, accounted for 75.52% of total irrigation amount, on the other hand, decreasing tendency of precipitation was obvious, and groundwater depth dynamic in upstream of the branch canals was more dramatic than downstream because of surface water irrigation infiltration, under the unified condition of water use efficiency, ratio of surface to groundwater irrigation amount was negative correlation with area of the groundwater depth beyond 11 m, meanwhile, groundwater depth demonstrated negative correlation with the ratio of surface to groundwater irrigation amount, moreover, alkaline trend of groundwater hydrochemistry during the normal season in the research area was obvious because of phreatic evaporation and the agricultural irrigation from wells, along with irrigation from surface inflow of Yellow River, quality of groundwater hydrochemistry during the dry season was ameliorative greatly. Consequently, it was very important to the agriculture sustainable production that well-canal combined irrigation patterns alleviated extremely alkaline trend of the groundwater hydrochemistry and played a positive role of root layer soil salinity leaching.

Analysis of the Carbon Footprint and Its Environmental Impact Factors for Living and Travel in Shijiazhuang City

By using methods of carbon footprint analysis, and impacts of population, affluence and technology （IPAT）, this article analyzes the carbon footprints of residence and travel, and their influential factors for different urban residential incomes, using 1,500 household questionnaires in Shijiazhuang city, Hebei province. The results show that the process of urban residents improving their living standards is also a driving factor in the increase of their carbon footprints; at the same time, the progress in technology has a positive impact on reducing the carbon footprints of urban residence. This article suggests that some measures, such as promoting energy-saving buildings and central heating supply, and establishing the convenient and comfortable public transport system, should be taken to reduce the carbon footprints of residence and travel in Shijiazhuang city.

The environment of coal mining areas and the economic evaluation of the land reclamation

The environment impact of the coal resources mining was analyzed. The method of economic evaluation for the coal mining was established to analyze land destruction. The opportunity cost method was used to quantitatively analyze and estimate the economic loss of the land destruction by coal mining. At the same time, the dump land reclamation of the Yuanbaoshan Open Pit was taken as an example to evaluate environmental and economical benefit with the method of economic evaluation for the coal mining areas land reclamation.

Subsurface Drainage Impact Assessment-in Ibshan, Egypt

This paper aims to mitigate the impacts of subsurface drainage system in Ibshan, Egypt on the environment. For studying and analyzing these impacts, data are collected concerning before and after the installation of the subsurface drainage system. The environmental impacts are set to be crops yields, salinity, and water table depth. Concerning crops yields, five crops are identified to study the effect of the subsurface drainage system on their productivity. Regarding salinity, the saline areas are investigated pre and post the subsurface drainage system. For the water table depth, the ground water table depths are reviewed before and after the subsurface drainage system. Also, the DRA1NMOD-S computer program is employed to determine the effect of the subsurface drainage system on the water table depth. It is concluded that the environmental impacts of the subsurface drainage system in Ibshan area are very good. The yields of five crops increased from 7% to 38%, 16.4% of saline areas are improved, and the ground water table depth is reduced by 10%. Also, an equation is obtained to predict the percentage decrease of ground water table depth according to the laterals spacing of the subsurface drainage system.

Eutrophication of Aquatic Ecosystems： A Viewpoint on the Environmental Impact of Climate Change

Environmental concerns associated with nutrient-oriented eutrophication phenomenon have become a serious issue and a major cause of water quality deficiency nowadays. This necessitated eutrophication to occupy a front seat in research accompanied with climate change. Climate change has revealed to be a key player and a main contributor in the occurrence of such phenomenon. This paper discusses the ever-growing concern about eutrophication as a cause of climate change. Climate change affects storms intensity, changing the precipitation regime and increasing temperature. These effects increase the nutrient loading diffusion and cause excessive nutrients accompanied with storm water runoff, domestic wastewaters, and agricultural discharges to pour into water bodies. Eutrophication conversely contributes in the global wanning by releasing greenhouse gases from deoxygenated waters and sediments. Some control and mitigation measures are needed to fight climate change and achieve desired water quality goals. These measures include mitigation of climate change causes, enhancement of natural ecohydrological processes, application of proper integrated water resource management and participation of communities and governments.

The Testing Intelligence System Based on Factor Models and Self-Organizing Feature Maps

Presented is a new testing system based on using the factor models and self-organizing feature maps as well as the method of filtering undesirable environment influence. Testing process is described by the factor model with simplex structure, which represents the influences of genetics and environmental factors on the observed parameters - the answers to the questions of the test subjects in one case and for the time, which is spent on responding to each test question to another. The Monte Carlo method is applied to get sufficient samples for training self-organizing feature maps, which are used to estimate model goodness-of-fit measures and, consequently, ability level. A prototype of the system is implemented using the Raven＇s Progressive Matrices （Advanced Progressive Matrices） - an intelligence test of abstract reasoning. Elimination of environment influence results is performed by comparing the observed and predicted answers to the test tasks using the Kalman filter, which is adapted to solve the problem. The testing procedure is optimized by reducing the number of tasks using the distribution of measures to belong to different ability levels after performing each test task provided the required level of conclusion reliability is obtained.

25 Years of sensory drive： the evidence and its watery bias

It has been 25years since the formalization of the Sensory Drive hypothesis was published in the American Naturalist （1992）. Since then, there has been an explosion of research identifying its utility in contributing to our understanding of inter- and intra-specific variation in sensory systems and signaling properties. The main tenet of Sensory Drive is that environmental characteristics will influence the evolutionary trajectory of both sensory （detecting capabilities） and signaling （detectable features and behaviors） traits in predictable directions. We review the accumulating evidence in 154 studies addressing these questions and categorized their approach in terms of testing for environmental influence on sensory tuning, signal characteristics, or both. For the subset of studies that examined sensory tuning, there was greater support for Sensory Drive processes shaping visual than auditory tuning, and it was more prevalent in aquatic than terrestrial habitats. Terrestrial habitats and visual traits were the prevalent habitat and sensory modality in the 104 studies showing support for environmental influence on signaling properties. An additional 19 studies that found no supporting evidence for environmental influence on signaling traits were all based in terrestrial ecosystems and almost exclusively involved auditory signals. Only 29 studies examined the complete coevolutionary process between sensory and signaling traits and were dominated by fish visual communication. We discuss biophysical factors that may contribute to the visual and aquatic bias for Sensory Drive evidence, as well as biotic factors that may contribute to the lack of Sensory Drive processes in terrestrial acoustic signaling systems.

Field observation of total dissolved gas supersaturation of high-dams

One of the possible negative environmental effects of hydropower stations is the supersaturation of total dissolved gas (TDG) downstream of high-dams,which can lead to gas bubble disease or even death of fish. By taking the TDG as the main study object,the paper launched the TDG field observations on Zipingpu,Three Gorges,Ertan,Manwan,Dachaoshan,Gongzui and Ertan dams in China. The factors affecting TDG generation and dissipation were explored. Energy dissipation structures,spill rates and operation patterns were the main factors causing TDG supersaturation. TDG saturations are essentially the same in the hydro-electric tail water and in the upper reaches,so hydro-electric tail water can be less TDG supersaturated through mixing downstream. The main factors affecting the dissipation process of the supersaturated TDG were tributary convergence,water depth and turbulence. TDG supersaturation was unevenly distributed in both the vertical and transverse directions. This study is important because it adds to the accumulating experience of TDG field observations of dam projects in China,and because it objectively and impartially evaluates the impacts of supersaturated TDG. The study also provides field data and references for future studies of TDG supersaturation caused by high-dams.