VALUATION OF IMPROVED IRRIGATION EFFICIENCY FROM AN EXHAUSTIBLE GROUNDWATER SOURCE1

This paper presents estimates made via a recursive linear programming model of the net benefits of improving irrigation application efficiency from an exhaustible groundwater source. Net benefits were derived for different application efficiency levels under furrow, sprinkler, and LEPA irrigation systems. In addition, net benefit estimates were obtained for the transition across irrigation systems. Solutions from the model indicate that low crop prices have a differential impact on net benefits across irrigation application efficiencies and irrigation systems. Also, the more limited groundwater situations consistently reduce the economic incentive to adopt improved irrigation application techniques across all irrigation systems.     

The role of media exposure, social exposure and biospheric value orientation in the environmental attitude-intention-behavior model in adolescents

This paper explores the hypothesis that contextual environments (media exposure and social exposure) and biospheric value orientation are important antecedents to the attitude-intention-behavior model ( [Ajzen, 2001] and [Ajzen, 2002] ) in the context of environmental psychology. Data for this investigation were obtained from a random sample of 2106 (1073 males and 1025 females) high school students in Hong Kong. A path analysis demonstrates that adolescents’ social exposure and media exposure are associated with biospheric value orientation. The biosperhic value orientation is found to mediate between the contextual variables (media exposure and social exposure) and environmental attitude. This environmental attitude, in turn, mediates the relationship between this value orientation and behavioral intention to act environmentally. Results show that both adolescents’ behavioral intention and degree of social exposure are associated with their environmental behavior. Overall, this article provides empirical support for the proposed path model. The article concludes by presenting theoretical and practical implications for future research in environmental psychology.     

EFFECT OF WATER QUALITY STANDARDS ON FARM INCOME,RISK, AND NPS POLLUTION1

ABSTRACT: Enforceable standards play a crucial role in the design and implementation of most water quality policies. The impacts of these standards on farm income and nonpoint source (NPS) pollution can provide valuable information to develop economic policies that can improve water quality with minimal loss in income and minimal risk. This study uses an integration of nonlinear programming and a simulation model to assess the impacts of enforceable standards at technology and farm boundary levels. The results indicate that the type of pollutant regulated, enforcement type, and the level of standard had a significant impact on farm income and water quality. Choice of farm boundary standards over technology standards is dependent on the impact of the policy on other NPS pollutants, in addition to the reduction of nitrate and phosphorus pollutants. Enforcing farm boundary standards on nitrates had desirable effects on subsurface and percolate nitrogen and variance in income. Technology standards were uncertain in their effects because of the restriction on the choice of technologies available to farmers. A comparative policy analysis considering incentives, multiple impacts, transaction costs of implementation, and regional consideration is important to an effective policy design.     

MANAGING TAIWAN'S RESERVOIR WATERSHEDS BY THE ZONING APPROACH1

ABSTRACT: For many years, a commonly used strategy for source water protection in Taiwan has been setting up arbitrary, fixed‐width buffer zones near sensitive waters, such as water‐supply reservoirs, and prohibiting any development in their watersheds. However, such regulations are now often viewed as infringing by the government on landowners' property rights, a situation that has led to citizen protests. This paper describes a proposed strategy that is water‐quality based and uses a quantitative zoning approach. A reservoir's watershed is divided into several zones beginning from the normal water line to the divide. Different levels of best management practices (BMPs) are required for controlling runoff pollution in different zones. The layout of the management zones is based on a number of factors such as reservoir classification, water quality conditions, and physical characteristics of the watershed. The goal of promoting such an approach is to try to balance the needs of watershed development and water quality protection. A case study using the Tapu Reservoir Watershed in Northern Taiwan as an example for illustrating the proposed zoning approach is presented.     

Sources of productive efficiency: International comparison of iron and steel firms

Using a time-varying stochastic frontier model, this paper examines the technical efficiency of firms in the iron and steel industry to try to identify the factors contributing to the industry's efficiency growth. Industry observers and policymakers tend to cite most frequently three possible sources of efficiency growth: privatization; economies of scale; and vintage of equipment. Our study corroborates these factors. Based on our findings, which pertain to 52 iron and steel firms over the period of 1978–1997, privatization is likely to improve the efficiency of iron and steel firms to a great extent as evidenced in various industries. This study also provides systematic evidence that iron and steel production shows economies of scale. In addition, newer vintages of equipment are found to be closely correlated with higher levels of efficiency. This clearly indicates that investment in new plants and equipments is critical in pursuit of efficiency in the iron and steel industry.     

Application of life-cycle assessment to type III environmental declarations

The objective of this research is to develop a desirable type III environmental declaration format for the industrial consumer. A total of five different scenarios were chosen for the presentation of life-cycle assessment results in a format that meets the requirements of a type III environmental declaration. Life-cycle assessment of an electronic component was performed for this purpose. Environmentally significant impact categories and input/output items of a product system derived from the life-cycle assessment are presented in this format. Presenting these information concisely in a standardized format would accelerate the communication of environmental aspects of materials and components in a product supply chain. Thus the type III environmental declaration can be a useful instrument for the manufacturing of an ecoproduct.     

Statistical evaluation of geochemical parameter distribution in a ground water system contaminated with petroleum hydrocarbons

A shallow-depth ground water area was investigated to identify the dominant processes governing the distribution of hydrocarbon contaminants and hydrogeochemical parameters. The ground water in the study site has been highly contaminated with petroleum hydrocarbons. A preliminary pump-and-treatment remediation technology was applied for 4 yr at the site. Multivariate analyses were applied to hydrogeochemical data obtained before and after the rainy season. The pump-and-treatment application, indigenous biodegradation, and mixing by precipitation recharge are the major factors or events involved in the distribution of geochemical parameters of the ground water in the study area. Site-specific artificial pavement also played an important role in the evolution of the ground water chemistry. A conventional graphical analysis method (Piper plot) of major ions did not effectively reveal these effects. In this study, we demonstrate the usefulness of multivariate analysis (factor and cluster analyses) using biodegradation indicator parameters, as well as major cations and anions, for the study of the ground water system in the hydrocarbon-contaminated site.     

The trends of composite environmental indices in Korea

In this paper we construct for the first time an annual Composite Environmental Index from 1986 to 1995 in Korea, which is useful for evaluating the efficiency of environmental policies. Nine types of environmental problems are examined. On average, the composite index has increased annually by 5.3% over the 1986-1995 period, which implies that overall environmental quality has deteriorated gradually during this period. Problems such as the greenhouse effect, loss of biodiversity, natural resource depletion, and ecotoxication led to deterioration of environmental quality in the 1990s.     

Environmental and economic impacts of water scarcity and market reform on the Mooki catchment

Over-allocation of irrigation water has led to widespread environmental degradation in the Murray-Darling Basin (MDB) in Australia, prompting discussions of the water efficiency performance of irrigated industries. There is increasing pressure for irrigators to adopt water efficient practices in line with ecologically sustainable principles, especially with current drought conditions. However, there is great uncertainty surrounding the available practices to improve irrigation efficiency from both ecological and economic standpoints. This paper examines the economic and environmental impact of several possible water efficient practices and government policies, using an interdisciplinary approach combining biophysical modelling and economic modelling. This is done for the case-study of the Mooki catchment in the MDB, located in northern New South Wales, Australia.