tailieunhanh - MORTALITY AND MORBIDITY BENEFITS OF AIR POLLUTION ABSORPTION BY WOODLAND: Forestry Commission

The findings suggested that a 20% loss in the wooded area due to urbanization in Los Angeles would lead to a 14% increase in ozone concentrations. Nowak et al. (2000) provided a more detailed consideration of the net effect on ozone levels for urban areas in the North Eastern United States, but the findings were less clear. The model produced found an increase in tree cover to both increase and decrease ozone levels throughout the day. Between the hours of 5am and 19:00 a net decrease in ozone levels of was recorded due to urban trees, but during the evening there. | Social Environmental Benefits of Forestry Phase 2 MORTALITY AND MORBIDITY BENEFITS OF AIR POLLUTION ABSORPTION BY WOODLAND Report to Forestry Commission Edinburgh from Neil A. Powe and Kenneth G. Willis Centre for Research in Environmental Appraisal Management University of Newcastle http cream December 2002 Social Environmental Benefits of Forestry Phase 2 MORTALITY AND MORBIDITY BENEFITS OF AIR POLLUTION ABSORPTION BY WOODLAND Neil A. Powe and Kenneth G. Willis December 2002 1. Introduction Air pollution has a long history perhaps reaching its peak during the industrial revolution. Although such extreme pollution is not observed today in Britain poor air quality remains a problem for human health. Physical damage functions relating health mortality and morbidity to air pollution levels have been estimated over a number of years in different countries. Although the net effect of pollutants on health is unclear the Committee of the Medical Effects of Air Pollution COMEAP set up by the UK government has found the strongest link between health and pollution to be for particulates PM10 sulphur dioxide SO2 and ozone O3 Department of Health 1998 . A subsequent study by the Department of Health i999 investigated the link between deaths brought forward and hospital admission caused by air pollution and economic cost and found this cost to be substantial. Although the main consideration of policy must be the reduction in pollution at source there has been an increasing recognition that the biosphere is an important sink for many pollutants with plant canopies being considered more effective than other land uses. Thus the biosphere provides benefits additional to those associated directly with their aesthetic and wildlife characteristics. Plants facilitate the uptake transport and assimilation or decomposition of many gaseous and particulate pollutants. Indeed the layered canopy structure of trees which has evolved to maximise photosynthesis and the .