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盐碱泡沼广泛分布于东北地区的中、西部,是该区域宜渔国土资源的主要类型之一.根据1988~1995年东北松辽平原农业综合开发的实践,本文以大安市试验示范区为例,初步介绍了盐碱泡沼渔业开发的6项主要技术措施,以供同类地区借鉴。 相似文献
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吉林省西部大安古河道区是松辽平原农业综合开发的重点区域之一.在对古河道区域内的渔业资源进行全面调查的基础上,本文初步探讨了区域内各类渔业资源的开发利用途径. 相似文献
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东北松辽平原农业资源的开发措施王春裕(中国科学院沈阳应用生态研究所,沈阳110015)王曦(辽宁省科学技术信息中心,沈阳110015)松辽平原是我国东北地区松花江与辽河的冲积平原,南北长1000多km,东西宽400多km,地势平坦,土质肥沃,河)11... 相似文献
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胜利油田位于我国黄河三角洲地区,潜水位高,水的矿化度大。生态环境恶劣,对植物尤其对木本植物的生长不利,整个地区生长的多是抗盐碱能力强的草本植物。针对油田的特殊环境条件,综合有关资料,介绍了以沙枣为代表的植物特性,特别强调了其抗盐碱、降低土壤矿化度和潜水位、增加土壤有机质和引起植被变化的特性。指出黄河三角洲也有些土质较好的、适于作物和木本植物生长的地区,改良盐碱地可以以这些地区为基点,放射性地向外逐步试验沙枣的种植,以探索改善生态环境的途径。努力做到边发展经济,边改善环境,达到经济效益、社会效益和环境效益三统一。 相似文献
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查干湖的综合开发与利用 总被引:10,自引:0,他引:10
本文就松辽平原具有代表性的平原型半咸水湖泊-查干湖的生物源和理化环境状况进行了分析,并在此基础上探讨了渔业资源的综合开发,提出了切实可行的开发措施,以期为我国开发同类型湖泊提供参考。 相似文献
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亚欧第二大陆桥沿线中部地区生态环境现状及综合治理研究刘建甫,顾家(新疆维吾尔自治区科学技术委员会乌鲁木齐830011)2沿线中部地区生态环境与经济发展要求的基本适应性分析2.1沿线中部地区的开发建设与生态环境变迁2.1.1前苏联在中亚三国的开发建设和... 相似文献
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1987~1996年,达川地区在土地复垦方面取得了较好成绩,共实施省、地、县复垦项目251个,区、乡以下自办开发项目1000多处,复垦面积1.46万ha,其中复垦耕地0.4万ha,净增耕地面积0.2万ha,实现新垦耕地与非农业建设用耕地增减持平有余,调整农业结构少占耕地1.1万ha.通过农业综合开发,以短养长、规模经营、加工增值等措施,该区土地开发呈现出高效益的局面,累计土地开发收入17.1亿元,生产粮食16.8万t。10年来,我们的主要作法是:①强化宣传教育,提高对资源开发重要意义的认识。全区每年利用6月国土宣传月和“6.25”土地日等… 相似文献
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Michael Zuykov Dmitry Gudkov Maxim Vinarski Emilien Pelletier David A. T. Harper Serge Demers 《The Environmentalist》2011,31(4):369-375
A distinct external shell abnormality, coarse seam, was found in a high percentage of the pond snail Lymnaea stagnalis (L.) collected near Chernobyl Nuclear Power Plant (NPP), Ukraine. The negative cytogenetical and hematological effects of
long-term irradiation on pond snails in the Chernobyl Exclusion Zone have been repeatedly reported; consequently, it has been
assumed that radioactivity may also affect shell morphology. However, due to the absence of this shell abnormality in pond
snails collected from two radioactive sites in Russia, it can be concluded that the appearance of abnormal shells in snail
population near Chernobyl NPP cannot directly be explained by the radioactive contamination. 相似文献
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William R. Herb Omid Mohseni Heinz G. Stefan 《Journal of the American Water Resources Association》2009,45(5):1164-1178
Abstract: A numerical model has been developed to simulate the hydraulic and heat transfer properties of a stormwater detention pond, as part of a simulation tool to evaluate thermal pollution of coldwater streams from stormwater runoff. The model is dynamic (unsteady) and based on principles of fluid mechanics and heat transfer. It is driven by hourly weather data, and specified inflow rates and temperatures. To calibrate and validate the pond model field data were collected on a commercial site in Woodbury, Minnesota. The relationship between pond inflow and outflow rates to precipitation was effectively calibrated using continuously recorded pond levels. Algorithms developed for surface heat transfer in lakes were found to be applicable to the pond with some modification, resulting in agreement of simulated and observed pond surface temperature within 1.0°C root mean square error. The use of an unshaded pond for thermal mitigation of runoff from paved surfaces was evaluated using the pond model combined with simulated runoff from an asphalt parking lot for six years of observed rainfall events. On average, pond outflow temperature was 1.2°C higher than inflow temperature, but with significant event‐to‐event variation. On average, the pond added heat energy to runoff from an asphalt parking lot. Although the pond added total heat energy to runoff, it did reduce the rate of heat outflow from the pond by an order of magnitude due to reductions in volumetric outflow rate compared with the inflow rate. By reducing the rate of heat flow, the magnitude of temperature impacts in a receiving stream were also reduced, but the duration of impacts was increased. 相似文献
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我区城市排水生物稳定塘(污水库)功能,利用现状及对策简析 总被引:3,自引:2,他引:1
生物稳定塘在我区城市污水处理、利用中具有相当重要的作用,在今后相当长的时间内它将继续存在,生物稳定塘使用中存在的问题也反映了我区城市污水处理及排水利用系统的运行水平及要害问题,须通过综合决策、集中治理、强化管理等手段加以解决。 相似文献
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C. Tiyamani V. O. Shanholtz T M. Younos S. J. Thomson 《Journal of the American Water Resources Association》1994,30(2):335-341
ABSTRACT: A design procedure to determine optimum size for a sediment detention pond is presented. The procedure is based on simulating the sediment removal efficiency of the pond in conjunction with temporal variations in rainfall and potential land use and/or management options. The simulation procedure is based on a combined probabilistic-deterministic modeling approach. The probabilistic model generates daily rainfall with hourly increments for a selected site. The deterministic model simulates sediment yield and concentration for drainage area (pond inflow) and sediment trapping efficiency of the pond. The sediment yield and concentration in pond effluent is estimated from the difference between sediment inflow to the pond and sediment trapped by the pond. As an example, the procedure is applied to determine optimum design for a sediment detention pond in a surface mined area using several pond design options and alternative mining operation/land reclamation strategies. 相似文献
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氧化塘技术是处理工业废水常用的方法之一。对桩西采油厂的氧化塘设置了5个监测点位,每月监测4~8次。由监测数据可知,氧化塘温度决定藻类、细菌和其他水生物优势种属的演替;COD的去除效果受季节影响较小;塘内水流受风向影响较大;对石油类物质的去除效果比较稳定;挥发酚的去除与季节有较大关联;硫化物的去除率很高。分析结果表明,该氧化塘运转状况良好,但应注意来水状况。 相似文献
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Poach ME Hunt PG Reddy GB Stone KC Matheny TA Johnson MH Sadler EJ 《Journal of environmental quality》2004,33(3):844-851
Ammonia (NH3) volatilization is an undesirable mechanism for the removal of nitrogen (N) from wastewater treatment wetlands. To minimize the potential for NH3 volatilization, it is important to determine how wetland design affects NH3 volatilization. The objective of this research was to determine how the presence of a pond section affects NH3 volatilization from constructed wetlands treating wastewater from a confined swine operation. Wastewater was added at different N loads to six constructed wetlands of the marsh-pond-marsh design that were located in Greensboro, North Carolina, USA. A large enclosure was used to measure NH3 volatilization from the marsh and pond sections of each wetland in July and August of 2001. Ammonia volatilized from marsh and pond sections at rates ranging from 5 to 102 mg NH3-N m(-2) h(-1). Pond sections exhibited a significantly greater increase in the rate of NH3 volatilization (p < 0.0001) than did either marsh section as N load increased. At N loads greater than 15 kg ha(-1) d(-1), NH3 volatilization accounted for 23 to 36% of the N load. Furthermore, NH3 volatilization was the dominant (54-79%) N removal mechanism at N loads greater than 15 kg ha(-1) d(-1). Without the pond sections, NH3 volatilization would have been a minor contributor (less than 12%) to the N balance of these wetlands. To minimize NH3 volatilization, continuous marsh systems should be preferred over marsh-pond-marsh systems for the treatment of wastewater from confined animal operations. 相似文献
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Stormwater ponds are commonly used in residential and commercial areas to control flooding. The accumulation of urban contaminants in stormwater ponds can lead to a number of water quality problems including high nutrient, chemical contaminant, and bacterial levels. This study examined the interaction between land use and coastal pond water quality in a South Carolina residential subdivision pond. Eutrophic levels of chlorophyll and phosphorus were present in all seasons. Harmful cyanobacterial blooms were prevalent during the summer months. Microcystin toxin and fecal coliform bacteria levels were measured that exceeded health and safety standards. Low concentrations of herbicides (atrazine and 2,4-D) were also detected during summer months. Drainage from the stormwater pond may transport contaminants into the adjacent tidal creek and estuary. A survey of residents within the pond's watershed indicated poor pet waste management and frequent use of fertilizers and pesticides as possible contamination sources. Educational and outreach activities were provided to community members to create an awareness of the water quality conditions in the pond. Pond management strategies were then recommended, and selected mitigation actions were implemented. Water quality problems identified in this study have been observed in other coastal stormwater ponds of varying size and salinity, leading this project to serve as a potential model for coastal stormwater pond management. 相似文献
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An investigation of double-glass-covered trapezoidal salt-gradient solar pond coupled with reflector
G. S. Dhindsa 《International Journal of Green Energy》2018,15(2):57-68
In the present study, a trapezoidal salt-gradient solar pond (TSGSP) has been investigated experimentally. The top surface of solar pond has been covered with double-glass cover in order to reduce the evaporative and convective losses from the top. This results in increase of temperature even in the top zone of the solar pond and leads to more volume utilization for heat storage in the pond. A reflector made of aluminium sheet has been used to enhance the solar intensity on the solar pond during sunny hours. A procedure, to determine optimum tilt angle of reflector in order to utilize maximum amount of solar energy at noon, has been proposed. The use of reflector enhanced the average solar intensity on the top surface of solar pond by 22%. The maximum average temperature of trapezoidal solar pond with glass cover and reflector has been observed to be 70.5°C. The thermal efficiencies of LCZ, NCZ and UCZ for the trapezoidal solar pond with double-glass cover and reflector have been estimated to be 32.73%, 23.22% and 5.30%, respectively. In addition to experimental investigation, the sunny area ratio of TSGSP has been theoretically computed and compared with the cuboid solar pond having same top surface area and depth in order to see the effect of pond shape on sunny area ratio. The average yearly sunny area ratio of trapezoidal solar pond has been determined to be 11% higher than that of cuboid one. 相似文献