Cadmium: Simulation of environmental control strategies to reduce exposure

The effects of selected environmental control strategies on human dietary and respiratory exposure to environmental cadmium (Cd) have been simulated. For each control strategy, mean Cd dietary and respiratory exposures are presented for a twenty-year simulation period.Human exposures related to cadmium are associated with both process waste disposal and product disposal. Dietary exposure is by far the dominant mechanism for Cd intake. Dietary exposure related to aqueous discharges is primarily a result of municipal sludge landspreading, whereas that associated with emissions to the atmosphere derives mainly from the deposition on cropland of airborne particulates from product incineration. Only relatively small dietary exposure reductions are possible through restrictions on anysingle Cd use. Combinations of waste management and environmental control measures promise greater reductions in dietary and respiratory exposure than those achievable through use restrictions.Work supported by Office of Toxic Substances U.S. Environmental Protection Agency.     

The significance of environmental impacts: an exploration of the concept

Since environmental impact assessment (EIA) is concerned primarily withsignificant environmental impacts, the concept of impact significance deserves to be defined and applied rigorously. In this article use of the term over the past 15 years in EIA documentation is reviewed. Some recent attempts at elucidating the concept are summarized. Four perspectives on impact significance that emerged from a series of workshops on the ecological basis for EIA are presented. These perspectives include (a) statistical (related to problems of isolating project-induced changes from natural variation), (b) ecological (related to the importance of project-induced changes from a purely ecological perspective), (c) social (related to the acceptability of project-induced changes in important environmental attributes), and (d) project (related to whether project-induced changes will indeed influence project decision making). The following synthesis is proposed: Any exercise in judging the significance of an environmental impact should thoroughly consider (a) the importance of the environmental attribute in question to project decision makers, (2) the distribution of change in time and space, (c) the magnitude of change, and (d) the reliability with which change has been predicted or measured. The implications of considering these factors are discussed.     

Learning about knowledge management for improving environmental impact assessment in a government agency: the Western Australian experience

How does knowledge management (KM) by a government agency responsible for environmental impact assessment (EIA) potentially contribute to better environmental assessment and management practice? Staff members at government agencies in charge of the EIA process are knowledge workers who perform judgement-oriented tasks highly reliant on individual expertise, but also grounded on the agency’s knowledge accumulated over the years. Part of an agency’s knowledge can be codified and stored in an organizational memory, but is subject to decay or loss if not properly managed. The EIA agency operating in Western Australia was used as a case study. Its KM initiatives were reviewed, knowledge repositories were identified and staff surveyed to gauge the utilisation and effectiveness of such repositories in enabling them to perform EIA tasks.     

ISO 14 001 at the farm level: analysis of five methods for evaluating the environmental impact of agricultural practices

Faced with society's increasing expectations, the Common Agricultural Policy (CAP) review considers environmental management to be an ever more critical criterion in the allocation of farm subsidies. With the goal of evaluating the environmental friendliness of farm practices, France's agricultural research and extension services have built a range of agricultural/environmental diagnostic tools over recent years. The objective of the present paper is to compare the five tools most frequently used in France: IDEA, DIAGE, DIALECTE, DIALOGUE and INDIGO. All the tools have the same purpose: evaluation of the impact of farm practices on the environment via indicators and monitoring of farm management practices. When tested on a sample of large-scale farms in Picardie, the five tools sometimes produced completely different results: for a given farm, the most supposedly significant environmental impacts depend on the tool used. These results lead to differing environmental management plans and raise the question of the methods' pertinence. An analysis grid of diagnostic tools aimed at specifying their field of validity, limits and relevance was drawn up. The resulting comparative analysis enables to define each tool's domain of validity and allows to suggest lines of thought for developing more relevant tools for (i) evaluating a farm's environmental performance and (ii) helping farmers to develop a plan for improving practices within the framework of an environmental management system.     

Ecological risk and accessibility analysis to assess the impact of roads under Habitats Directive

We propose a method for the appropriate assessment of adverse effects of roads in compliance with the European Union Habitats Directive. The method incorporates an analysis of ecological risk of edge effects by the proposed roads with the related increase in accessibility. The method was tested on 30 km of planned forest roads inside an 8,000-ha reserve included in two Natura 2000 sites. As a result, the cumulative effect of 19 road segments was judged as not significantly affecting the integrity of the sites, although they made accessible an extra 314 ha. On the basis of the accessibility calculation, 20 ha of land were set aside from forest exploitation as a mandatory mitigation measure. The method objectively determined the cumulative adverse effects, enabled comparison of plan revisions and alternatives and proved to measure direct and indirect significant effects with a realistic effort in terms of field survey and geographic information system processing.     

Managing environmental impacts of energy development: Air quality in the Hunter Region,New South Wales,Australia

The Hunter Region in New South Wales, Australia, is undergoing rapid economic development based on its black coal resources. Cumulative impacts of new projects cannot be easily assessed with the traditional environmental impact statement. This article examines air quality impacts, and presents a systems analysis model to assist environmental management. The model consists of an input-output model of the regional economy and an air dispersion model. Results are obtained for sulfur oxides and fluorides.     

Analyzing the Impacts of Dams on Riparian Ecosystems: A Review of Research Strategies and Their Relevance to the Snake River Through Hells Canyon

River damming provides a dominant human impact on river environments worldwide, and while local impacts of reservoir flooding are immediate, subsequent ecological impacts downstream can be extensive. In this article, we assess seven research strategies for analyzing the impacts of dams and river flow regulation on riparian ecosystems. These include spatial comparisons of (1) upstream versus downstream reaches, (2) progressive downstream patterns, or (3) the dammed river versus an adjacent free-flowing or differently regulated river(s). Temporal comparisons consider (4) pre- versus post-dam, or (5) sequential post-dam conditions. However, spatial comparisons are complicated by the fact that dams are not randomly located, and temporal comparisons are commonly limited by sparse historic information. As a result, comparative approaches are often correlative and vulnerable to confounding factors. To complement these analyses, (6) flow or sediment modifications can be implemented to test causal associations. Finally, (7) process-based modeling represents a predictive approach incorporating hydrogeomorphic processes and their biological consequences. In a case study of Hells Canyon, the upstream versus downstream comparison is confounded by a dramatic geomorphic transition. Comparison of the multiple reaches below the dams should be useful, and the comparison of Snake River with the adjacent free-flowing Salmon River may provide the strongest spatial comparison. A pre- versus post-dam comparison would provide the most direct study approach, but pre-dam information is limited to historic reports and archival photographs. We conclude that multiple study approaches are essential to provide confident interpretations of ecological impacts downstream from dams, and propose a comprehensive study for Hells Canyon that integrates multiple research strategies.     

TUGAI: An Integrated Simulation Tool for Ecological Assessment of Alternative Water Management Strategies in a Degraded River Delta

The development of ecologically sound water allocation strategies that account for the needs of riverine ecosystems is a pressing issue, especially in semiarid river basins. In the Aral Sea Basin, a search for strategies to mitigate ecological and socioeconomic deterioration has been in process since the early 1990s. The Geographic Information System–based simulation tool TUGAI has been developed to support the policy determination process by providing a simple, problem-oriented method to assess ecological effects of alternative water management strategies for the Amudarya River. It combines a multiobjective water allocation model with simple, spatially explicit statistical and rule-based models of landscape dynamics. Changes in environmental conditions are evaluated by a fuzzy habitat suitability index for Populus euphratica, which is the dominant species of the characteristic riverine Tugai forests. Water management scenarios can be developed by altering spatiotemporal water distribution in the delta area or the amount of water inflow into the delta. Outcomes of scenario analysis are qualitative comparisons of the ecological effects of different options for a time period of up to 28 years. The given approach utilizes different types of knowledge, from quantitative hydrological data to qualitative local expert knowledge. The main purpose of the tool is to integrate the knowledge in a comprehensive way to make it available for discussions on alternative policies in moderated workshops with stakeholders. In this article, the modules of the tool, their integration, and three hypothetical scenarios are presented. Based on the experience gained when developing the TUGAI tool, we propose that the general framework can be transferred to other areas where tradeoffs in water allocation between the environment and other water users are of major concern. The potential for a simulation tool to structure and inform a complex resource management situation by involving local experts and stakeholders in the development of possible future scenarios will become increasingly valuable for transparent and participatory resource management.     

An analysis of the implementation of an environmental management system in a local public administration

The Environmental Management System (EMS) is commonly implemented in private firms. However, on the basis of a strengths, weaknesses, opportunities and threats (SWOT) analysis, our work analyzes the consequences of implementing an EMS within the context of local public administrations, particularly regarding the City Council of Ohanes in Almería (Spain). This is the first European corporation to implement an EMS according to the ISO 14001 Standard, certified by the Spanish Association of Normalization and Certification. Its analysis would be equivalent to the Shumpeterian "market innovator study", so that public administration "followers" can take advantage of the derived benefits and of minimizing the negative effects of such an experience. On the other hand, we show that the economic and environmental advantages derived from the EMS go beyond the activities that the City Council is in charge of. They have spillover effects that extend them to all economic activities in the municipality and these effects are expected to be increased in the medium and long-term perspective. In this paper, we compare the costs and benefits that the municipality obtains in two cases: the City Council implements the EMS or it does not implement it. The main objective of this article is to show the economic and environmental advantages obtained by a municipality when it is only the City Council who is implementing an EMS. It is logical to suppose that this case study can stimulate other municipalities to use this instrument, even if the economic and environmental characteristics of the municipality are different.     

Evaluation of the economic and environmental impact of converting cropland to forest: a case study in Dunhua county, China

The Sloping Land Conversion Program (also known as "Grain for Green" or the Upland Conversion Program) for converting cropland to forest is one of China's most ambitious environmental initiatives, and is one of the world's largest land-conservation programs with a budget of RMB 337 billion (over US$ 40 billion). Although environmental impacts have played a vital role in the general reasoning and argumentation for forest plantations, environmental impact analyses have often received less attention than economic analyses in the planning of plantation forestry projects. The overall goal of this paper is to evaluate the program's environmental impact considering the farmer's interests and the potential social benefits due to carbon sequestration in different scenarios based on household and field survey data in Dunhua County. Our findings are that: (1) in many cases, the program did not give adequate consideration to land productivity and environmental heterogeneity when selecting plots; (2) more than half of the reforestation plots were on flat cropland (slopes of less than 5 degrees ); (3) in five of the eight townships, net incomes on reforested land were substantially above or below previous crop incomes, raising questions about the efficiency of the allocation of compensation to farmers participating in the program; (4) the potential carbon co-benefit increased the NPV of the program by 5954-7009 RMB/ha. In conclusion, we recommend that more attention should be paid to the quality of reforestation programs rather than just their scale and note that consideration of potential carbon sequestration co-benefits enhances the benefits of cropland conversion programs.     

Political benefits as barriers to assessment of environmental costs in Brazil's Amazonian development planning: The example of the Jatapu Dam in Roraima

Development projects are rapidly changing the landscape in Brazilian Amazonia. Environmental impact assessments have been required since 1986, and the regulatory system is evolving as precedents are set by each new development project. The Jatapu Dam in Roraima provides an illustration of underlying impediments to assessment of environmental costs and to due consideration being given to these assessments when decisions are made. The high priority placed on the dam by the Roraima state government is unexplainable in terms of economic returns. The place of the dam in a long-term political strategy provides the best of several possible explanations, any one of which is incompatible with a rational weighing of economic and environmental costs and benefits. A number of lessons can be drawn from the experience of Jatapu, but some of the problems have no solution. The barriers to rational decision making illustrated by Jatapu apply to development projects in many parts of the world.     

Geostatistical spatiotemporal analysis of air temperature as an aid to delineating thermal stability zones in a potential show cave: implications for environmental management

Air temperature in several galleries of the Covadura System (Sorbas Gypsum Karst, Almería) was measured at monthly intervals over a period of 1 year. The spatial temperature distribution for each month was modeled in a geostatistical framework. The mean trend of the air temperature and the difference between each experimental temperature measurement and this trend were calculated over space and time. Both the trend and residual component were characterized using a geostatistical space-time model. A large spatial trend of the air temperature was found due to the orientation of galleries within the cave system and as a function of the distance from the main cave entrance. Kriging was used for the spatial estimation of the time covariance of the residuals. This enabled the delimitation of the cave into three zones of varying environmental risk in the event of being opened to visits by the public, according to the degree of stability of air temperature over space and time. The influence of human presence on the spatial temperature distribution was assessed using data collected during a year (2000/2001) in pilot galleries opened to the public. An average visit corresponding to August was selected comprising 16 people over a period of 53 min. This average visit influenced the spatial temperature pattern at distances of more than 90 m from the cave entrance, according to the geostatistical model adopted. Within this zone the mean thermal increment generated by human presence was estimated to be 0.26 degrees C. The spatiotemporal mathematical model of the cave air temperature has been revealed as a useful tool for the environmental management of show caves.