MUNICIPAL AND INDUSTRIAL WATER SUPPLY IN CIUDAD JUAREZ,MEXICO1

Rapid industrialization and population growth in the north Mexican desert city of Ciudad Juarez are placing a serious strain on the city's municipal water resources. Water deliveries and service area have more than doubled over the past decade, and plans for additional expansion are presently being implemented. This expansion is already contributing to water table declines and salinity increases in the Mexican portion of the Heuco Bolson, the sole source of water for the city. Continued mining of the limited fresh water reserves should produce serious water supply problems in the near future. New estimates of future water consumption incorporated into a digital aquifer simulation model indicate that these problems may show up much sooner than was anticipated in previous investigations. The results of this study point to the need to accelerate the gathering of basic data on alternative water resources. The problems faced by Cd. Juarez are illustrative of the kinds of difficulties likely to confront other rapidly developing cities of the arid zone.     

SEASONAL PUMPING VARIATION EFFECTS ON WELLHEAD PROTECTION AREA DELINEATION1

ABSTRACT: Delineation of a welihead protection area (WHPA) is the key element in welihead protection programs for drinking water supplies. WHPAs are often delineated under idealized conditions using simple steady-state assumptions, which lead to an incorrect estimation of area and geometry. In this paper, we compare the results from a simple steady-state procedure commonly employed in WHPA delineation with a more complex transient approach that allows consideration of seasonal variation in pumping rates. We also introduce a transient procedure to delineate time-related capture zones using a numerical ground water flow and transport model. Welihead delineation is examined for two municipal wells in Tipton, Oklahoma, using a ten-year time-of-travel criterion. In the steady-state procedure, where we assumed constant pumping rates, we used GPTRAC, a semi-analytical model, and MOC, a numerical model. The capture zone delineated by GPTRAC is comparable in shape with the capture zone delineated by MOC but not in size due to the differences in solution schemes. In the transient procedure, we used MOC and considered the seasonal variation in pumping rates. The capture zones delineated in this procedure were larger than the capture zones delineated by the steady-state procedure using the same model. Further analysis showed that a higher drawdown was predicted in the transient procedure than in the steady-state procedure, which is the reason for larger capture zones.     

秦岭─黄淮平原交界带近五百年的旱涝研究

本文根据旱涝史料及现代观测资料，运用旱涝等级评定法和农田水分平衡法，对秦岭─黄淮平原交界带自１４７０～１９８０年逐年的旱涝状况进行了评定，重建了秦岭─黄淮平原交界带１４７０～１９８０年近５００ａ的旱涝等级序列，在此基础上讨论了旱涝发生的基本规律。运用山地─平原交界带气候边际效应的观点，探讨了山地─平原交界带气候边际效应与旱涝的关系．     

印染工业园废水集中处理的探讨

近年来，印染工业园在各地纷纷建立，大大促进了当地经济的发展。本文论述了当前印染工业园废水集中处理设计和运行过程中需要注意的问题，并提出了相应的对策，以期为相关工业园设计和研究提供参考。     

模糊综合评价法在液氯运输过程安全性评估的应用

将模糊综合评价方法和层次分析法用于危险化学品运输过程安全性评估,综合考虑在过程中危化品、人、车、路、环境等五个方面因素对整个过程安全性的影响,得到运输过程安全性等级。运用现有的泄漏模拟公式定量计算发生泄漏事故后所产生的危险区域,为人员疏散提供了决策帮助。最后以液氯运输过程为例进行安全评估,并计算泄漏后危险区域的范围。     

基于GIS的寒地黑土区农业气候资源评价——以绥化市为例

以黑龙江省降水量、日照时数和≥10℃积温多年平均值等气象资料为数据源,利用地理信息系统技术对绥化市的农业气候资源进行了评价。评价结果表明,绥化市的降水量、日照时数和≥10℃积温变化具有明显的纬度地带性,但降水量的空间变化趋势是随着纬度的增高而增加,这与日照时数和≥10℃积温的空间分布趋势相反;从光热水的组合来看,绥化的光热水等农业气候资源的综合评价指数范围为3.4—6.6,且该值有从南向北逐渐递减的趋势。     

基于多元线性回归的宗地地价评估--以东营市为例

基准地价系数修正法作为大量评估宗地地价的一种方法，得到了广泛的应用，但是由于修正体系因素的权重确定多是通过特尔斐法来确定，主观性比较强。以东营市为例，探讨了用多元线性回归模型的方法进行修正因素影响的计算，并对宗地地价进行了评估。     

THE FLEXIBLE TOLERANCE METHOD FOR ESTIMATING HYDROLOGIC PARAMETERS IN THE ROOT ZONE1

In this study, a constrained minimization method, the flexible tolerance method, was used to solve the optimization problems for determining hydrologic parameters in the root zone: water uptake rate, spatial root distribution, infiltration rate, and evaporation. Synthetic soil moisture data were first generated using the Richards' equation and its associated initial and boundary conditions, and these data were then used for the inverse analyses. The results of inverse simulation indicate the following. If the soil moisture data contain no noise, the rate of estimated water uptake and spatial root distribution parameters are equal to the true values without using constraints. If there is noise in the observed data, constraints must be used to improve the quality of the estimate results. In the estimation of rainfall infiltration and surface evaporation, interpolation methods should be used to reduce the number of unknowns. A fewer number of variables can improve the quality of inversely estimated parameters. Simultaneous estimation of spatial root distribution and water uptake rate or estimation of evaporation and water uptake rate is possible. The method was used to estimate the water uptake rate, spatial root distribution, infiltration rate, and evaporation using long‐term soil moisture data collected from Nebraska's Sand Hills.     

A Methodological Approach for Designating Management Zones in Mount Spil National Park, Turkey

/ This study was undertaken to (1) determine the suitability of ecosystems within Mount Spil National Park (Turkey) to human activities by a systematic zoning procedure, and (2) provide the basis for developing sound management strategies based on natural-cultural resource attributes of the park. After assessing natural-cultural resources and human activity requirements, the suitability of three zones (Strict Protection Zone, SPZ; Restricted Use Zone, RUZ; and Recreation and Administration Zone, RAZ) for proposed human activities/land uses was determined in order to maintain ecological sustainability and integrity through a weighting-ranking methodology, based on a grid cell resolution of 1 km x 1 km. Results showed that out of the three management zones, the RUZ in which the recreational activities that do not require physical developments are allowed constituted 82% of the park area as the first priority management zone. The proposed zoning procedure is believed to be a key step to improve management for both the study area and other national parks with the similar landscape features.     

美国海岸带管理和环境评估的框架及启示

本文介绍了美国《海岸带管理法案》所反映的海岸带管理的基本问题,包括海岸带管理的目标、重点领域、方法、策略与政策框架;还介绍了美国的海岸带区划,以及海岸环境评估的指标体系和评估标准。在此基础上提出所受启示与借鉴之处。