探討產業減污之經濟衝擊與河川品質改善——可計算一般均衡模型之應用

Emission Charges, Economic Impacts, and Water Quality Improvement - A CGE Approach

產業在生產的過程中排放大量廢棄物或污染物至環境媒體（Environmental Media）如空氣、水、及土地等，其對環境品質之威脅，隨著產業密集程度持續提高，與日俱增。由於產業所產生的污染為環境品質惡化的主要原因之一，產業減污已被認為是改善環境品質的一項重要策略。然而，值得注意的是，藉由實施產業減污策略以改善環境品質時，很可能會對一地區經濟活動產生一般均衡效果（General Equilibrium Effects）。而且，此經濟衝擊中可能包括環境品質改善後對人類活動之經濟效益。本研究以臺灣地區為個案，利用一般均衡分析（General Equilibrium Analysis）架構為基礎，聯結可計算一般均衡模型與環境品質模型，探討課徵產業排污費（Pollutant　Emission Charges）對經濟及河川水質之影響。並且以產業廢水中因含高濃度的總溶解固體（Total Dissolved Solids），致承受河川水體或農業灌溉水鹽度過高，而影響水稻田生產力為例，在模型中考量環境品質回饋效果對產業生產力之影響。本文分析層面包括：（1）探討課徵排污費對各產業部門產品與價格之影響；（2）分析課徵排污費對總體經濟重要指標值之影響；（3）推估課徵排污費在短期內對河川污染之改善情形；以及（4）估算河川水質改善後對經濟活動產生之回饋效益。 Industrial pollution is one of the major reasons for environmental deterioration. Imposing emission charges to reduce industrial pollutant emissions has been seen as an important approach to improve environmental quality. However, imposing emission charges on production activities may have general equilibrium effects on an economy because of the inter-relationships among economic sectors. In addition, the economic effects may include the benefits to an economy as a result of environmental quality improvement. The current paper proposes an analytical framework in which a computable general equilibrium model was linked with two environmental models to examine the economic impacts of water pollutant emission charges on the economy and water quality in Taiwan. The results of policy simulations show: (1) the percentage changes in sectoral output volumes and prices under alternative emission charge rates; (2) the estimated impacts of emission charges on selected macro economic variables; (3) the estimated short-term direct effects of emission charges on water quality improvement; and (4) the feedback effects of water quality improvement on the economy.