Reclaimed water is an important resource for irrigation, and exploration in making full use of it is an important way to alleviate water shortage. This paper analyzes the effects of irrigation with reclaimed water through field trials on the content and distribution of heavy metals in both tomatoes and the soil. By exploring the effects of reclaimed water after secondary treatment on the content and distribution characteristics of heavy metals in tomatoes and the heavy metal balance in the soil-crop system under different conditions, the study shows that there are no significant differences in the heavy metal content when the quantity of reclaimed water for irrigation varies. Reclaimed water for short-term irrigation does not cause pollution to either the soil environment or the crops. Nor will it cause the accumulation of heavy metals, and the index for the heavy metal content is far below the critical value of the national standard, which indicates that the vegetables irrigated with reclaimed water during their growth turn out to be free of pollutants. The heavy metals brought into the soil by reclaimed water are less than that taken away by the crops. The input and output quantities have only small effects on the heavy metal balance in the soil. This paper provides a reference for the evaluation and safety control of irrigation with reclaimed water.

This paper based on a theoretical study of the supported liquid membrane separation technology, explores the appropriate liquid membrane separation system, makes a study on the Pb (II) transmission behavior in the PC-88A-kerosene-HCl dispersion supported liquid membrane system and reviews influence of the feed liquid pH value, volume ratio between the membrane liquid and analytic agent, HCI concentration during analytic phase and initial Pb (II) transmission concentration. The results show that the migration of Pb (II) is well completed for 190 min with the migration rate being up to 95% on the premise that the feed liquid pH is equal to 6.0, Pb (II) initial concentration of 3.0 × 10⁻³ mol/L, HCl concentration during the stripped and dispersed phase is 4.0 mol/L, volume ratio between the stripped liquid and organic phase is 40:160 and that of the conventional supported liquid membrane is only 72.4%. The dispersion supported liquid membrane is characterized by higher transmission efficiency, stable membrane system and long membrane service life. The procedure has provided accurate results with zinc borne waste water treatment.

A recent study decomposed the changes in industrial water use into three hierarchies (output, technology, and structure) using a refined Laspeyres decomposition model, and found monotonous and exclusive trends in the output and technology hierarchies. Based on that research, this study proposes a hierarchical prediction approach to forecast future industrial water demand. Three water demand scenarios (high, medium, and low) were then established based on potential future industrial structural adjustments, and used to predict water demand for the structural hierarchy. The predictive results of this approach were compared with results from a grey prediction model (GPM) (1, 1). The comparison shows that the results of the two approaches were basically identical, differing by less than 10%. Taking Tianjin, China as a case, this study predicts that industrial water demand will continuously increase, reaching 580 million m³, 776.4 million m³, and approximately 1.09 billion m³ by the years 2015, 2020 and 2025 respectively. It is concluded that Tianjin will soon face another water crisis if no immediate measures are taken. This study recommends that Tianjin adjust its industrial structure with water savings as the main objective, and actively seek new sources of water to increase its supply.

Collective action is a basic premise for the effective protection of open public resources. The characteristics and the environment of open public resources, however, also constitute many “bottlenecks” to collective action, which means that there is a “paradoxical” relationship between collective action and open public resources. Therefore, the key to protecting open public resources is to construct a collective action mechanism that can break these “bottlenecks”. In the case of three different forms of contract system implemented by Yongjia County, Zhejiang Province, China for the fishery resources of Nanxi River, the first two contracts were caught up in the “tragedy of the commons” and a legality crisis because they did not form a collective action mechanism to protect resources. The sub-contract with the aim of protecting and resting the Nanxi River started in 2005 and has constructed a collective action mechanism of consensus, sharing, common participation, joint discussion and co-management, and worked out a rationale of how to form collective action in the process of open public resource protection, which is worth exploring and promoting. This study aims to explore the bottlenecks which limit collective action in the process of resource protection, and to provide practical policy recommendation for solving them.

Global warming has exerted a significant influence on water cycle in global drainage basins, involving various aspects associated with ecology, society, economy and human activity. Therefore, accurate forecast and analysis of climatic change trend are the prerequisite to disaster alleviation and prevention. The paper selects a large scale climate predictor by modeling steps and evaluation indicators for a statistical downscaling model and establishes a statistical relation between atmospheric circulation factor and precipitation and air temperature at eight stations in Wei River Basin in Shaanxi Province for a global climate model output based on hydrological data for Wei River Basin in Shaanxi Province. A study was made of the simulated precipitation and air temperature in Wei River Basin by principal component analysis and multiple linear regression and achieved favorable results. The approach is better in physical significance and is characterized by accurate climate simulation, simple calculation for statistical downscaling and is convenient for application in various climate models.