CAJ | 학술논문

随着我国环境污染状况日趋严重,政府提出要把节约资源作为我国的基本国策,保护生态环境。而不断扩大的贸易活动对资源的需求增加使得人们开始认为贸易扩张或许是我国环境污染状况难以改善的原因之一。因此在我国全面提高开放水平的重要阶段,研究贸易对环境将产生何种影响具有重要意义。围绕这一问题国内外学术界展开了大量探讨,但现有理论和经验证据还没有给出统一的答案。由于贸易与环境之间存在反向因果关系,而且发展中国家的数据准确性也缺乏可信度,因此必须在回归时考虑内生性问题。在存在内生性的前提下使用OLS回归可能会产生严重的偏误,因此本文通过构造汇率冲击变量——中国各省份最大贸易伙伴国的加权汇率——作为贸易开放的外部工具变量来研究贸易与环境的因果影响。本文利用中国31个省份2003-2011年工业SO2排放强度作为环境质量的替代变量,应用2SLS方法进行估计。结果显示,外贸依存度每提高1%,单位产值的工业SO2排放将会减少2.5%-3.2%;当运用工业废气、工业固体废弃物和工业废水排放强度作为环境质量代理指标时,贸易开放的弹性估计值也显著为负;出口和进口依存度的增加都能减少工业SO2排放,但进口的作用更加明显。因此,贸易开放对我国的污染减排将起到正向作用。建议政府积极扩大对外开放,并更加注重发挥进口对减轻环境污染的促进作用。
수착아국배경오염상황일추엄중,정부제출요파절약자원작위아국적기본국책,보호생태배경。이불단확대적무역활동대자원적수구증가사득인문개시인위무역확장혹허시아국배경오염상황난이개선적원인지일。인차재아국전면제고개방수평적중요계단,연구무역대배경장산생하충영향구유중요의의。위요저일문제국내외학술계전개료대량탐토,단현유이론화경험증거환몰유급출통일적답안。유우무역여배경지간존재반향인과관계,이차발전중국가적수거준학성야결핍가신도,인차필수재회귀시고필내생성문제。재존재내생성적전제하사용OLS회귀가능회산생엄중적편오,인차본문통과구조회솔충격변량——중국각성빈최대무역화반국적가권회솔——작위무역개방적외부공구변량래연구무역여배경적인과영향。본문이용중국31개성빈2003-2011년공업SO2배방강도작위배경질량적체대변량,응용2SLS방법진행고계。결과현시,외무의존도매제고1%,단위산치적공업SO2배방장회감소2.5%-3.2%;당운용공업폐기、공업고체폐기물화공업폐수배방강도작위배경질량대리지표시,무역개방적탄성고계치야현저위부;출구화진구의존도적증가도능감소공업SO2배방,단진구적작용경가명현。인차,무역개방대아국적오염감배장기도정향작용。건의정부적겁확대대외개방,병경가주중발휘진구대감경배경오염적촉진작용。
With China＇s increasingly serious environmental pollution, saving resources has become one of the government＇s basic policies to protect our environment. People begin to think that the need for resources by growing international trade maybe one of the reasons of our heavy pollution. It is meaningful to research the impact of trade openness that may have on the environment in the important stage of improving opening-up in all aspects. The literatures so far, both theoretical and empirical, are largely inconclusive. We must consider endogeneity problem since there is reverse causal relationship between trade and environment and there are accuracy problems of data in developing countries. Regression may have serious bias using OLS method under the premise of endogeneity problem. This paper created an instrumental variable of exchange rate shock, which is the weighted average exchange rate of China provinces＇ largest trade pa~ner countries, to control the endogeneity of trade openness and estimates the causal effect of trade to environment. We used industrial Sulfur dioxide （SO2 ）emissions for 31 provinces of China covering the years from 2003 to 2011 to proxy environment quality, and then made estimation with 2SLS techniques. We found that every one percentage increase in trade-GDP ratio decreases the SO2 intensity by 2.5 - 3.2 percentage points. The elasticity is also significantly negative when using industrial waste gas, solid waste and waste water intensities as environmental quality indexes. Increasing in export-GDP ratio and import-GDP ratio will be good to the emission of SOs , while the effect of import is more obvious. Therefore trade openness is found to benefit the emission reduction in China. So it is recommended that the government can expand trade opening actively and focus more on import to alleviate environmental pollution.