摘要
【目的】以森林吸收烟粉尘为例,实证检验烟粉尘对居民呼吸系统相关疾病的影响,定量分析空气污染与公共健康的关系。【方法】首先,沿用文献回顾阐述大气污染引发呼吸系统相关疾病,森林可以通过减少空气污染物来影响人体健康的相关研究;其次,基于我国30个省(市、区)7年的面板数据,分别通过最小二乘法(OLS)、面板模型、3SLS估计烟粉尘对公共健康的影响;第三,着重采用3SLS方法克服颗粒物排放的内生性问题,从而更加准确地评价环境污染对公共健康的负面影响,有效解释地区间健康水平异质性;第四,采用不同排放物作为工具变量对估计结果进行稳健性检验,以保证结论的可信度。【结果】1)OLS估计显示,烟粉尘对公共健康的影响非常显著,烟粉尘排放量每增加1%,万人中死于肺癌和呼吸性疾病的人数相应增加0.568%和0.488%。2)随机效应模型(RE)估计显示,烟粉尘对肺癌死亡人数的显著性水平有所降低,在10%水平下显著为正,对呼吸系统疾病的死亡人数影响非常显著,烟粉尘排放量每增加1%,二者死亡人数分别增加0.207%和0.467%。3)采用外生的病虫害发生面积作为森林面积的工具变量来解决烟粉尘排放的内生性问题。基于工具变量的三阶段最小二乘估计(3SLS)显示,森林面积显著影响烟粉尘排放水平,森林面积每增加1%,烟粉尘排放量大约降低0.884%;烟粉尘排放量每增加1%,万人中死于肺癌人数将增加0.777%,死于呼吸系统疾病的人数将增加0.704%,并且均高于用OLS、随机效应模型估计出的值,说明后2种方法会低估空气污染对公共健康的影响。4)人均GDP和人口密度正向作用于居民公共健康水平,人均医疗支出对居民公共健康水平在1%水平下显著为负,即人均医疗支出每增加1%,万人中肺癌及呼吸系统疾病死亡人数将分别降低0.362%和0.543%。【结论】鉴于森林通过吸收烟粉尘可提高公共健康水平,为了进一步提高公共健康水平,除了通过法律和强制措施从源头治理污染外,还需要大力提倡植树造林、提高森林覆盖率、扩大烟粉尘吸收能力强的树种面积、有效提高病虫害防治水平等。
【Objective】 Taking forest absorption of smoke and dust as an example,this study empirically examined the effects of smoke and dust on the related diseases of residents ＇respiratory system,thus quantitatively analyzed of the relationship between air pollution and public health.【Method】A literature review and qualitative analysis were conducted to explore respiratory-related diseases caused by air pollution,forest affect human health by reducing air pollutants.In addition,using panel data from China,a quantitative analysis was carried out to estimate the effects on public health of dust by OLS,panel model,3SLS.Especially,using 3SLS method to overcome endogenous problem caused by emissions of particulate matter,thus more accurately evaluate the negative impact of environmental pollution on public health,and effectively explain the regional heterogeneity.Finally,using different emissions as an instrument to estimate the robustness of the result,ensure the reliability of conclusions.【Result】1） OLS estimates show that the impact on public health of dust is very significant： as the smoke and dust emissions increase 1%,the number of people dying from lung cancer and respiratory diseases corresponding increase 0.568% and 0.488%,respectively.2） Random effect model （RE） show that lung cancer deaths caused by the smoke and dust decreased dramatically,and is significantly positive with deaths fromrespiratory diseases at 10% level.As the smoke and dust emissions increase 1%,the number of deaths from lung cancer and respiratory diseases correspondingly increase 0.207% and 0.467%,respectively.3） Using the area of pests and diseases as an instrument of forest area,endogeneity smoke and dust emissions are solved.Based on 3SLS,this study shows that forest area will significantly affect the level of smoke and dust emission,as forest area increase by 1%,the smoke and dust emissions reduce by 0.884% approximately.Whereas the smoke and dust emissions increase by 1%,the number of people dying from lung cancer and respiratory diseases will increase by 0.777% and 0.704%,respectively.These value are higher than those obtained by OLS,and random effect model,which shows that the last two method underestimate the impacts of air pollution on public health.4） Other control variables influence on residents of the respiratory system,the per capita GDP and population density exhibit positively effect on public health,whereas,health expenditure per capita for residents show negatively effect on public health at 1% significance level.It is indicated that as per capita health expenditure increase 1%,the deaths from lung cancer and respiratory will decrease 0.362% and0.543%,respectively.【Conclusion 】 Forest will improve the level of public health by absorbing smoke and dust emissions.In order to improve the level of public health,it is important that not only control pollution from the source through legal and enforcement measures,but also promote afforestation,increase forest coverage rate,expand absorption ability of the tree area,effectively improve the level of prevention and control of plant diseases and insect pests,etc.
作者
周海川
Zhou Haichuan(Research Institute of Forestry Policy and Information, CAF Beijing 100091)
出处
《林业科学》
EI
CAS
CSCD
北大核心
2017年第8期120-131,共12页
Scientia Silvae Sinicae
基金
浙江省省院合作林业科技项目"森林疗养基地认证标准与指标体系研究"(2016SY17)
中央级公益性科研院所基本科研业务费专项资金资助项目(CAFYBB2017QA020)
