前沿 | 意昂2經院奚錫燦等在《美國科意昂2院刊》(PNAS)上發表文章

Policy Simulation Laboratory, Zhejiang University

Xican Xi

China Center for Economic Studies, School of Economics, Fudan University,

Xin Tang

Center for Economic Development Research, Economics and Management School of Wuhan University

Deming Luo

Center for Research of Private Economy, School of Economics, Zhejiang University

Baojing Gu

Department of Land Management, Zhejiang University

Shu Kee Lam𓀎，Deli Chen

School of Agriculture and Food, The University of Melbourne

Peter M. Vitousek

Department of Biology, Stanford University

Abstract:

化肥和農藥等農用化學品的過度施用，嚴重威脅了我國的生態環境和人民身心健康，對我國農業的可持續發展提出了嚴峻挑戰👦🏿。本研究發現，農業經營規模是影響我國農用化學品施用量的重要因素👩‍🦯。利用從中國農村家庭調查數據庫（CRHPS）調取的數據，本研究發現，控製其他因素後🎅，戶均耕地面積每增加1％🦸🏿，每公頃化肥和農藥施用量分別下降0.3％和0.5％，而農業勞動生產率則上升幾乎一個百分點。利用不同來源的農業調查數據🚵🏿‍♂️💉，本研究得出了非常相似的結論。發達國家的歷史經驗表明🚮，農業經營規模一般隨著經濟發展而擴大。在我國✔️，由於勞動力市場和農地使用權市場存在嚴重的資源錯配，盡管我國宏觀經濟在過去四十年間快速持續發展，農業經營規模卻沒有相應擴大。本研究的結論表明，消除勞動力市場和農地使用權市場的資源錯配，適度擴大農業經驗規模，可以有效減輕我國農用化學品的過度施用問題。

Understanding the reasons for overuse of agricultural chemicals is critical to the sustainable development of Chinese agriculture. Using a nationally representative rural household survey from China, we found that farm size is a strong factor that affects the use intensity of agricultural chemicals across farms in China. Statistically, a 1% increase in farm size is associated with a 0.3% and 0.5% decrease in fertilizer and pesticide use per hectare (P < 0.001), respectively, and an almost 1% increase in agricultural labor productivity, while it only leads to a statistically insignificant 0.02% decrease in crop yields. the same pattern was also found using other independently collected data sources from china and an international panel analysis of 74 countries from the 1960s to the 2000s. while economic growth has been associated with increasing farm size in many other countries, in china this relationship has been distorted by land and migration policies, leading to the persistence of small farm size in china. removing these distortions would decrease agricultural chemical use by 30–50% and the environmental impact of those chemicals by 50% while doubling the total income of all farmers including those who move to urban areas. removing policy distortions is also likely to complement other remedies to the overuse problem, such as easing farmer's access to modern technologies and knowledge, and improving environmental regulation and enforcement.

Keywords

crop yield👩🏼‍🎓；environmental protection；fertilizer use efficiency；socioeconomic； barriers urbanization

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