The design of integrated monitoring systems to provide early indications of environmental/ecological changes.

One of the important goals of the next several decades is to achieve and maintain ecologically sustainable development of the biosphere. However, the management of ecological systems is rather difficult, largely because of uncertainties in long-term predictions of environmental and ecological behaviour. Thus, one of the objectives for integrated monitoring should be to provide early indications of impending changes so that mitigative actions can be taken.This paper includes a discussion of the factors to be considered in the design of early-warning monitoring systems, and gives some examples. One approach that appears to be particularly promising is that of identifying, quantifying and monitoring the stresses, feedbacks and component lags in the environmental-ecological system being studied.

Environmental impact assessment: National approaches and international needs.

This paper examines the spread and development of 'environmental impact assessment' (EIA) since the enactment of the U.S. Environmental Policy Act on January 1, 1970, which established for the first time under any jurisdiction the formal requirement that an EIA be made and that an 'environmental impact statement' (EIS) be filed prior to implementation of certain major development projects.The paper is divided into three parts. In the first part, we briefly review the forms of EIA introduced in the western industrial countries and contrast these with developments in the socialist countries of Eastern Europe, and in the Third World. The approaches to EIA adopted by five countries - the United States, Australia, Canada, the Federal Republic of Germany, and the Soviet Union - are used to illustrate the types of national approaches that have been followed. In the second part of the paper, we use some questions raised by impact assessments as codified in legislation or regulations at the national level to highlight some of the limitations of impact assessment. Finally, we turn to international impact assessments and describe the modest progress made to date. Key impediments to the development of appropriate conceptual and institutional frameworks and methodologies for international EIAs are noted.In conclusion, we offer some suggestions about needed actions at both the national and international levels.

The estimation and interpretation of air quality trends, including some implications for network design.

A review is given of methods being used to identify and interpret trends in air quality data from single stations and from networks of stations. Some comments are also included concerning the problem of designing networks which will identify trends as quickly as possible, thus providing early warnings of significant changes in air quality.

Biological consequences of land use.

The primary goals of land-use planning are enunciated. A plea is made for consideration of the total biosphere and not just its separate components. The environmental impact statement process is reviewed and some suggestions made for its strengthening. Moves for international adoption of this process are noted, as well as the concept of eco-development currently under examination by UN agencies.