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1.8 EN\nRONME.NTAL RESEAKCH AND DEVELOPMENT 



In the more than twenty years since the nation first saw the images 

 from (he moon. Kicntific knowledge about the components of the earth's 

 biosphere and the effects of human activity on them has increased, public 

 concern has grown, and national, state, and local governments have enacted 

 a wide range of environmental programs. As a result, progress has been made 

 m some of the problem areas that first attracted widespread attention in 

 the late 1960s. A 1991 report by the Organization for Economic Cooperation 

 and Development (OECD) listed a number of achievements. These included 

 reduction of urban air p>ollution by lead, sulfiir dioxide, and paniculate 

 matter; reduced pollution of waterways by organic substances as a result 

 of treatment of household and indusuial wastewater, a decrease in the number 

 of accidental oil spills; increases in the area of protected land and habitats; 

 increased forest resources; better protection of a number of game species; 

 a growing population of several threatened sp>ecies; and reduction in the 

 release into the environment of cenain dangerous chemicals, such as DDT, 

 PCBs, and mercury compounds." 



Some time after the 1971 Stockholm Conference on the Environ- 

 ment, however, a review by the United Nations Environment Program found 

 that human interventiotis in rutural sj'stcms had increased on a massive 

 scale, and that there wis an urgent need for remedial and preventive action. 

 Those interventions had been accompanied by momentous advances in in- 

 dustrial activity and agricultural produaion and in human longevity and 

 health.' 



The past two decades have thus seen the p>crsistencc of some threats 

 to the environment and the emergence of dangerous ne* ones. While there 

 is less sulfur dioxide in the air in some cities, nitrogen oxides, urban smog, 

 and fine particulates continue to be major problems. Growing concentra- 

 tions of carbon dioxide and other greenhouse gases threaten to raise global 

 temj>eratures. In the middle and late 19S0S. the discovery of a thinning in 

 the ozone layer over Antarctica led to the judgment that the eanh's pro- 

 teaive ozone layer is being depleted much more quickly in some regions 

 than had been thought. About 17 million acres of tropical forest arc esti- 

 mated to be disappearing each year, taking with them a wealth of biological 

 diversity that can never be replaced. Groundwaten, once thought to be in- 

 vulnerable to contamination, have deteriorated because of salinization and 

 pollution from urban runoff, pesticides, and seepage from contaminated 

 industrial sites. Soil continues to be degraded by erosion and pollution from 

 a wide range of sources, and development is putting pressure on critical 

 cnvironmenul areas such as coastal regions and «-etiands, farmland, and 

 natural preserves. Many areas are becoming more vulnerable to extreme events 

 such as droughts and floods. In shon, our planet is still very much in danger. 



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