胡杨内源保护酶系可以指征宏观生态行为效果吗--塔里木河下游生态输水效应案例研究

在宏观生态系统的恢复中,通常关注的层面至多达到个体水平,即只计测个体的存在和测定所关注的可视特征,而忽略了个体的生理反应,特别是在实施恢复生态工程时,大规模地重新构造生物生活资源结构,常常难以估测这种变化对生物的有效性,加之可视生态效果表达的滞后性和可测试的复杂性,常常造成效果遗漏.因此,增加微观(细胞)层面的反应指示指标,可捕捉细微的个体反应,更准确的指征生态效果在个体上实现反应的可能性,这对于丰富恢复生态学理论是具有重大意义的.本文以塔里木河下游生态恢复工程为载体,探索了以内源保护酶系活力变化为指征的个体对生态输水的响应,结果表明超氧歧化酶(SOD)、过氧化物酶(POD)和膜脂过氧化产物丙二醛(MDA)不仅对累积输水效果具有指示性,而且对短期水干扰具有敏感的指示性,相关关系也因受水而强化.     

小城镇环境保护规划存在的问题与对策

根据全国生态环境保护“十五”计划要求,在计划期间力争60％的小城镇完成环境保护规划,广西小城镇由于经济发展不平衡,部分小城镇还比较落后,且存在较多的环境问题,目前小城镇的环境保护规划尚未得到有效的开展,因此应及时找出问题和差距,并根据存在的问题作出相应的对策,在计划期内是可以完成小城镇环境保护规划的目标,为广西小城镇的可待续发展提供环境保障。     

河北省河口港址资源质量等级评价

河北省共有31个河口港址,广泛分布于河北省沿海地区。在实地调研和广泛收集数据的基础上,采用层次分析法和模糊综合评价法,对河北省河口港址的自然条件和社会经济状况进行了定性、定量分析。根据分析结果将河口港址资源划分为4个质量等级,提出了不同质量等级河口港址资源开发利用的具体措施。     

小型环境试验舱的研制及性能研究

自制小型环境试验舱的体积为0．17m^3，用产生甲醛的标准气体方法检验试验舱的稳定性、准确性及精密性。结果表明，试验舱稳定，无吸附，且有95％的精确性。通过测定试验舱内木板中甲醛释放量及释放规律检验试验舱的应用性能，测得甲醛释放规律与文献研究结果一致，表明该试验舱应用性能良好，因此该实验舱可用于检测室内装饰装修材料中污染物质释放量及释放规律的研究。     

渚滑川河口拦门沙演变特性

河口拦门沙的存在可导致径流流出不畅，并能引起一系列的河口生态及环境问题。特别是弯曲型河口，在波浪流、河川径流及弯道副流的共同作用下，拦门沙的形成及演变将更为复杂。通过对日本渚滑川河口多次实地调查资料的分析，揭示了渚滑川河口拦门沙的演变特性。结果表明：渚滑川河口修筑防波堤后，在东北方向的海洋入射波作用下，拦门沙由河口右岸发育并向左岸逐渐延伸扩展，其河水流动也相应由右岸偏向左岸一侧；不论河口有无拦门沙，3次洪水在右岸的最大冲深均稳定在-6m高程，且河床横剖面的形状基本不变，即汛期时该河口河床形状已达平衡状态。     

Nutrient Uptake in a Large Urban River1

Abstract: Small streams have been shown to be efficient in retaining nutrients and regulating downstream nutrient fluxes, but less is known about nutrient retention in larger rivers. We quantified nutrient uptake length and uptake velocity in a regulated urban river to determine the river’s ability to retain nutrients associated with wastewater treatment plant (WWTP) effluent. We measured net uptake of soluble reactive phosphorus (SRP), dissolved organic phosphorus, ammonium (NH₄), nitrate, and dissolved organic nitrogen in the Chattahoochee River, Atlanta, GA by following the downstream decline of nutrients and fluoride from WWTP effluent on 10 dates under low flow conditions. Uptake of all nutrients was sporadic. On many dates, there was no evidence of measurable nutrient uptake lengths within the reach; indeed, on several dates release of inorganic N and P within the sample reach led to increased nutrient export downstream. When uptake occurred, SRP uptake length was negatively correlated with total suspended solids and temperature. Uptake velocities of SRP and NH₄ in the Chattahoochee River were lower than velocities in less‐modified systems, but they were similar to those measured in other WWTP impacted systems. Lower uptake velocities indicate a diminished capacity for nutrient uptake.     

RIVER AMENITY EVALUATION: A REVIEW AND COMMENTARY1

ABSTRACT: During the past 15 years a number of methods have been developed that purport to evaluate the amenity values of rivers. Most methods are designed to identify the physical, biological, cultural, and esthetic features of a river or river corridor that are conducive to recreation, preservation, and other amenity values. This paper reviews and comments on 13 methods that evaluate amenity values. The methods are reviewed and discussed under three general headings: River Recreation Potential Evaluation, River Esthetic Evaluation, and River Preservation Evaluation. A final section of the paper identifies areas where improvements and further research are needed.     

THE APPLICATION OF HYDROLOGIC MODELS TO SMALL WATERSHEDS HAVING MILD TOPOGRAPHY1

ABSTRACT: The application of hydrologic models to small watersheds of mild topography is not well documented. This study evaluates the applicability of hydrologic models described by Huggins and the Soil Conservation Service to small watersheds by comparing the simulated and actual hydrograph for both gaged and ungaged situations. The annual maximum rainfall events plus storms exceeding 2.5 inches from 25 years of rainfall and runoff data for two small watersheds were selected for the model evaluations. These storms had a variety of patterns and occurred on many different watershed conditions. Simulated and actual hydrographs were compared using a parameter which contained volume, peak, and shape factors. One-half of the selected storms were used to calibrate the models. For both models, there were no significant differences between the simulated and actual runoff volumes and peak runoff rates. Parameters obtained during the calibration process and relationships developed to estimate antecedent moisture and to modify tabulated runoff curve numbers were used to simulate the runoff hydrograph from the remaining storms. These remaining storms or test storms were simulated only once in order to imitate an ungaged situation. In general, both the Huggins and SCS model performed similarly on the test storms, but the level of model performance was lower than that for the calibration storms. For both models, the two-day antecedent rainfall was more important than the five-day in determining antecedent moisture and modifying tabulated curve numbers. The time of concentration which resulted in good hydrograph simulations was about three times larger than that estimated using published empirical relationships.     

PLANNING LEVEL ESTIMATES OF THE VALUE OF RESERVOIRS FOR WATER SUPPLY AND FLOW AUGMENTATION IN NEW HAMPSHIRE1

: In general, the choice among reservoirs for water supply or flow augmentation is a multiobjective problem. Choices are based in part on the yield available from water supply reservoirs or, in the case of flow augmentation reservoirs, on the increase in low flows at downstream locations. Detailed estimates of these effects may be too costly for basin planning purposes. Thus this paper presents methods for rapid estimation of those quantities for New Hampshire. For water supply reservoirs, a composite empirical relation between Y95 (the draft available 95 percent of the time) and storage ratio, S*, is developed from previous studies in the region. For flow augmentation reservoirs, empirical relations between S* and degree of regulation, R*, are applied to each upstream regulating reservoir. Values of regulation arc then summed and divided by the mean flow at the downstream reach of interest. This parameter, (ΓR)*, is then related to increase in flow available 95 percent of the time by an empirical relation.     

INTER-STATE WATER DISPUTES: A CASE STUDY OF INDIA1

ABSTRACT: During the last 27 years of independence, a large number of inter-state water disputes cropped up over the use of rivers. Surprisingly enough, more disputes developed in this short period than in the earlier 200 years of the development of irrigation and so far none of the disputes has been permanently solved. The major rivers of India are all inter-state rivers and this is one of the more important reasons why some of them are not yet fully developed for irrigation or power production. The Union Government has set up, so far, only three tribunals to adjudicate inter-state disputes. But the problems do not end simply by setting up the tribunals. In practice, it has also proved a dilatory process. None of the tribunals has been successful in settling any dispute in the long years of their existence. There is no codified law prescribing rights and the notion of “equity” has come to prevail restraining the upper states from drawing such quantities of water as would injure the interests of the lower states. Though the general principle of equitable apportionment had been advocated many times, in practice each contending state had given this principle an interpretation that suited it. The basic principle would be to harness the rivers not for the benefit of a particular state but for the maximization of agricultural, industrial, and navigational potential in the areas served by the rivers.