长江流域的鱼类资源及其保护对策

长江水系的鱼类约有300种,其中鲤科鱼类占半数以上,主要的经济鱼类多数属于鲤科。对不同江段的鱼类资源作了简介,并提出了相应的保护措施。上游江段以维护生物多样性,保护特有种为主,需要建立鱼类自然保护区;中游应保证主要经济鱼类的自然繁殖条件,加强珍稀鱼类的人工繁殖放流工作,同时对湖泊幼鱼资源进行保护;下游应注意保持江水质量,严格遵守工业废水排放标准;河口江段应规定幼鲟保护期,建议每年6月15日至7月31日停止一切损害幼鲟资源的渔捞作业。     

长江河口越江工程在上海港建设中的重要作用

探讨了连接上海，崇明和江苏海门的长江河口桥隧工程在连接河口岛屿间交通，发挥崇明的区位优势，促进地区经济发展以及在上海港建设中的作用。详细论述了越江工程完成后上海新港的扩建，根据河口河水岸线的分布，提出了在横沙岛东滩修建人工岛的设想，最后对几种越江方案进行了分析比较，提出了作者的看法。     

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.     

Quantitative Assessment of Agricultural Runoff and Soil Erosion Using Mathematical Modeling: Applications in the Mediterranean Region

Three mathematical models, the runoff curve number equation, the universal soil loss equation, and the mass response functions, were evaluated for predicting nonpoint source nutrient loading from agricultural watersheds of the Mediterranean region. These methodologies were applied to a catchment, the gulf of Gera Basin, that is a typical terrestrial ecosystem of the islands of the Aegean archipelago. The calibration of the model parameters was based on data from experimental plots from which edge-of-field losses of sediment, water runoff, and nutrients were measured. Special emphasis was given to the transport of dissolved and solid-phase nutrients from their sources in the farmers' fields to the outlet of the watershed in order to estimate respective attenuation rates. It was found that nonpoint nutrient loading due to surface losses was high during winter, the contribution being between 50% and 80% of the total annual nutrient losses from the terrestrial ecosystem. The good fit between simulated and experimental data supports the view that these modeling procedures should be considered as reliable and effective methodological tools in Mediterranean areas for evaluating potential control measures, such as management practices for soil and water conservation and changes in land uses, aimed at diminishing soil loss and nutrient delivery to surface waters. Furthermore, the modifications of the general mathematical formulations and the experimental values of the model parameters provided by the study can be used in further application of these methodologies in watersheds with similar characteristics.     

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。     

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。     

Use of Streamflow Data to Estimate Base Flow/Ground‐Water Recharge For Wisconsin1

Abstract: The average annual base flow/recharge was determined for streamflow‐gaging stations throughout Wisconsin by base‐flow separation. A map of the State was prepared that shows the average annual base flow for the period 1970‐99 for watersheds at 118 gaging stations. Trend analysis was performed on 22 of the 118 streamflow‐gaging stations that had long‐term records, unregulated flow, and provided aerial coverage of the State. The analysis found that a statistically significant increasing trend was occurring for watersheds where the primary land use was agriculture. Most gaging stations where the land cover was forest had no significant trend. A method to estimate the average annual base flow at ungaged sites was developed by multiple‐regression analysis using basin characteristics. The equation with the lowest standard error of estimate, 9.5%, has drainage area, soil infiltration and base flow factor as independent variables. To determine the average annual base flow for smaller watersheds, estimates were made at low‐flow partial‐record stations in 3 of the 12 major river basins in Wisconsin. Regression equations were developed for each of the three major river basins using basin characteristics. Drainage area, soil infiltration, basin storage and base‐flow factor were the independent variables in the regression equations with the lowest standard error of estimate. The standard error of estimate ranged from 17% to 52% for the three river basins.     

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.     

COMPARATIVE EVALUATION OF THREE URBAN RUNOFF MODELS1

ABSTRACT: Three urban runoff models, namely, the Road Research Laboratory Model (RRLM), the Storm Water Management Model (SWMM) and the University of Cincinnati Urban Runoff Model (UCURM), were examined by comparing the model simulated hydrographs with the hydrographs measured on several instrumented urban watersheds. This comparison was done for the hydrograph peak points as well as for the entire hydrographs using such statistical measures as the correlation coefficient, the special correlation coefficient and the integral square error. The results of the study indicated that, when applying the three selected non-calibrated models on small urban catchments, the SWM model performed marginally better than the RRL model and both these models were more accurate than the UCUR model. On larger watersheds, the comparisons between the SWM model and the other two models would be likely even more favourable for the SWM model, because it has the most advanced flow routing scheme among the studied models.     

WATER HARVESTING TREATMENT EVALUATION AT GRANITE REEF1

ABSTRACT: Yearly runoff efficiencies (total runoff/total precipitation), threshold retentions (precipitation needed to initiate runoff), and runoff-efficiencies-after-thresholds were determined for several water-harvesting catchment treatments at the Granite Reef test site. This information was found to be useful for showing (1) overall performance of catchments with time; (2) the distribution of the precipitation among runoff, surface retention, and infiltration; (3) why, how, and when certain treatments weathered and failed; (4) when to repair treatments; and (5) how to design catchments (size, site preparation, material selection, etc.). New impermeable membranes with smooth surfaces yielded nearly 100% of the precipitation. An asphalt-fiberglass treatment continues this high efficiency after 10 years of weathering – polyethylene after 8; efficiency of butyl sheeting was high initially but decreased rapidly after 9 years weathering. A standard roofing treatment retained up to 30% of the precipitation in the gravel covering. A concrete catchment lost as much as 50% of the total precipitation through micropores and surface cracks. Silicone treatments rapidly lost repellancy and efficiency, while paraffin treatments have weathered 5 years with little loss of efficiency.