除湿机的冷凝水化学成分与空气环境质量的关系

本文采用家用除湿机作为空气水溶性物质采样器方法，并验证了该方法作为空气水溶性物质采样嚣的可行性。本文通过空气冷凝水化学成分与空气总悬浮微粒(TSP)可溶性化学成分的对比，得到水汽中大部分阴阳离子的含量只比TSP低1个数量级，而水汽中的微量元素含量与各种碳的浓度不都比TSP低，TSP中一般检测不出亚硝酸根，而水汽中则检出大量亚硝酸根。     

Enhanced water resource base for sustainable integrated water resource management

The article states the case for greatly enhanced reliance on desalination in the provision of freshwater. It argues that the concept of integrated water resource management (IWRM), should be expanded to routinely include desalination, and that sea water and brackish water should be listed among available sources of freshwater. In recent years, the price per m3 of freshwater obtained from desalination has steadily declined, and is now within competitive range of conventional sources, especially as extracting water from surface sources (rivers, lakes) is becoming increasingly expensive as well as ecologically harmful, and groundwater in many locations is saline or depleted. With the expectation that by 2020, five billion people will reside in megacities, today's conventional water resources are likely to become insufficient. As many of these megacities are located near ocean coasts, sea water seems a logical solution.     

MODELING SEDIMENT AND PHOSPHORUS LOSSES IN AN AGRICULTURAL WATERSHED TO MEET TMDLs1

ABSTRACT: This paper studies the effectiveness of alternative farm management strategies at improving water quality to meet Total Maximum Daily Loads (TMDLs) in agricultural watersheds. A spatial process model was calibrated using monthly flow, sediment, and phosphorus (P) losses (1994 to 1996) from Sand Creek watershed in south‐central Minnesota. Statistical evaluation of predicted and observed data gave r² coefficients of 0.75, 0.69, and 0.49 for flow (average 4.1 m³/s), sediment load (average 0.44 ton/ha), and phosphorus load (average 0.97 kg/ha), respectively. The calibrated model was used to evaluate the effects of conservation tillage, conversion of crop land to pasture, and changes in phosphorus fertilizer application rate on pollutant loads. TMDLs were developed for sediment and P losses based on existing water quality standards and guidelines. Observed annual sediment and P losses exceeded these TMDLs by 59 percent and 83 percent, respectively. A combination of increased conservation tillage, reduced application rates of phosphorus fertilizer, and conversion of crop land to pasture could reduce sediment and phosphorus loads by 23 percent and 20 percent of existing loads, respectively. These reductions are much less than needed to meet TMDLs, suggesting that control of sediment using buffer strips and control of point sources of phosphorus are needed for the remaining reductions.     

TEMPORAL CHANGES IN THE YADKIN RIVER FLOW VERSUS SUSPENDED SEDIMENT CONCENTRATION RELATIONSHIP1

ABSTRACT: Dynamic linear models (DLM) and seasonal trend decomposition (STL) using local regression, or LOESS, were used to analyze the 50‐year time series of suspended sediment concentrations for the Yadkin River, measured at the U.S. Geological Survey station at Yadkin College, North Carolina. A DLM with constant trend, seasonality, and a log₁₀ streamflow regressor provided the best model to predict monthly mean log₁₀ suspended sediment concentrations, based on the forecast log likelihood. Using DLM, there was evidence (odds approximately 69:1) that the log₁₀ streamflow versus log₁₀ suspended sediment concentration relationship has changed, with an approximate 20 percent increase in the log₁₀ streamflow coefficient over the period 1981 to 1996. However, sediment concentrations in the Yadkin River have decreased during the decade of the 1990s, which has been accompanied by a concomitant increase in streamflow variability. Although STL has been shown to be a versatile trend analysis technique, DLM is shown to be more suitable for discovery and inference of structural changes (trends) in the model coefficient describing the relationship between flow and sediment concentration.     

CHEMISTRY OF COALBED METHANE DISCHARGE WATER INTERACTING WITH SEMI‐ARID EPHEMERAL STREAM CHANNELS1

ABSTRACT: The objective of this study was to examine the chemistry of Coalbed Methane (CBM) discharge water reacting with semi‐arid ephemeral stream channels in the Powder River Basin, Wyoming. The study area consisted of two ephemeral streams: Burger Draw and Sue Draw. These streams are tributaries to the perennial Powder River. Samples were collected bimonthly from three CBM discharge points and seven channel locations in Burger Draw and Sue Draw. Samples were also collected bimonthly from the Powder River above and below the confluence of Burger Draw. Before sample collection, the pH and electrical conductivity (EC) were measured in the field. Samples were transported to the laboratory and analyzed for alkalinity, major cations, and anions. From the measurement of sodium (Na), calcium (Ca), and magnesium (Mg), practical sodium adsorption ratio (SARp) and true sodium adsorption ratio (SARt) were calculated. Results suggest pH and EC of CBM discharge water was 7.1 and 4.3 dS/m, respectively. The CBM discharge water consisted of higher concentrations of sodium and alkalinity compared to other components. The pH of CBM discharge water increased significantly (p = 0.000) in the downstream channel of Burger Draw from 7.1 to 8.84 before it joined with the Powder River. Dissolved calcium concentration of CBM discharge water decreased significantly (p = 0.000) in the downstream channel water. Subsequently, SARp increased approximately from 24 to 29. The SARt also increased significantly (p = 0.001) in the downstream channel water. For instance, SARt of CBM discharge water increased from 32.93 to 45.5 downstream channels after the confluence of Sue Draw with the Burger Draw. The only significant difference in water chemistry above and below the confluence of Burger Draw with the Powder River was pH, which increased from 8.36 to 8.52. The significant increase in SAR values of CBM discharge water in Burger Draw and Sue Draw tributaries suggest a careful monitoring of salinity and sodicity is needed if CBM discharge water is used for irrigation in semi‐arid environments. Results discussed in this study will be useful to downstream water users who depend on water for irrigation.     

TRANSIENT RESPONSE FUNCTIONS FOR CONJUNCTIVE WATER MANAGEMENT IN THE SNAKE RIVER PLAIN,IDAHO1

ABSTRACT: Increasing demands on western water are causing a mounting need for the conjunctive management of surface water and ground water resources. Under western water law, the senior water rights holder has priority over the junior water rights holder in times of water shortage. Water managers have been reluctant to conjunctively manage surface water and ground water resources because of the difficulty of quantification of the impacts to surface water resources from ground water stresses. Impacts from ground water use can take years to propagate through an aquifer system. Prediction of the degree of impact to surface water resources over time and the spatial distribution of impacts is very difficult. Response functions mathematically describe the relationship between a unit ground water stress applied at a specific location and stream depletion or aquifer water level change elsewhere in the system. Response functions can be used to help quantify the spatial and temporal impacts to surface water resources caused by ground water pumping. This paper describes the theory of response functions and presents an application of transient response functions in the Snake River Plain, Idaho. Transient response functions can be used to facilitate the conjunctive management of surface and ground water not only in the eastern Snake River Plain basin, but also in similar basins throughout the western United States.     

电石渣浆处理与资源化

针对电石渣浆处理的工艺流程和资源化途径进行了效益分析,工程实践表明:电石渣浆处理后,浆水回用作为生产用水,降低了乙炔生产成本.同时彻底解决电石渣含水率高的问题,利于企业开展资源化,值得在乙炔行业推广.     

经济欠发达山区矿泉水资源的开发利用--以梅州市为例

基于矿泉水与人体健康的关系、在社会经济发展中的作用,以及对梅州市矿泉水资源条件及其开发利用现状的调研,探讨了经济欠发达山区矿泉水资源的开发利用对策和前景.认为应统一资源管理,加强质量监督力度,打造优质品牌,提高市场竞争能力,争取与食品、旅游等部门联营,使矿泉水产品多样化、系列化;结合地方工业建设和梅州旅游市场需求,培育矿泉水消费市场.     

ClO2去除废水中石油类污染物的研究

就如何使用ClO2和O3对水中石油类污染物氧化去除进行了研究，确定了最佳反应时间、pH和氧化剂用量对去除率的影响。ClO2的最佳投加量应为有机物总量的1．5倍，反应时间可控制在20min上。ClO2处理pH5．0～6．5溶液时的去除效果最好。同时进行了O3的对照实验。分析了ClO2和O3在水处理应用中的优缺点。