近年来，随着“碳达峰”、“碳中和”战略的提出和经济向高质量发展、产业转型升级的需要，绿色金融成为了热门的研究主题。绿色金融的目的是通过引导资金的流向，支持节能环保清洁产业的发展，限制或淘汰落后产能，促进污染企业的技术升级和产业转型。随着全球生态环境恶化，贸易绿色化成为多数国家的共识。在世界经济进入下行期，我国出口呈现疲软的状态下，如何有效发挥绿色金融的政策工具的作用，促进我国出口质量的提升成为了一个非常有研究意义的课题。本文旨在通过实证研究探讨绿色金融政策对企业出口规模的影响及其作用机制。具体而言，本文以2012年《绿色信贷指引》政策为一次准自然实验，以2007年至2016年A股制造业上市公司为样本，以上市公司海外业务收入为被解释变量，以双重差分变量为解释变量，以反映企业基本面的若干特征变量为控制变量，构建双重差分模型，来探究绿色金融政策对企业出口规模的作用。随后本文将研究样本分为国有企业与非国有企业，中国东部地区企业、中部地区企业和西部地区企业来进行分析，考察绿色金融政策对各个子样本的出口规模的异质性影响。最后本文以波特效应理论，异质性企业贸易理论和中国的“出口-生产率”悖论理论为支撑，从融资约束和企业生产率视角探究绿色金融政策对企业出口规模的影响的作用机制。研究结果表明：第一、2012年《绿色信贷指引》政策对A股制造业上市公司中重污染企业的出口规模有显著的抑制作用。第二、该政策对A股制造业上市公司中重污染企业中的国有企业的出口规模的抑制作用不明显，对于非国有企业的抑制作用很显著。第三、该政策对A股制造业上市公司中重污染企业中位于中国西部地区的企业的抑制作用不明显，而对于位于中国中部地区和东部地区的企业的抑制作用显著，且对位于中部地区的企业的抑制作用最显著。本文通过机制分析研究证实了融资约束和企业生产率是绿色金融政策作用于企业出口规模的渠道。2012年《绿色信贷指引》政策对于高融资约束的A股制造业上市公司中重污染企业的出口规模的抑制作用更显著，且该政策提高了A股制造业上市公司中重污染企业的生产率，有助于企业的技术进步和转型升级，但由于中国“出口-生产率”悖论的存在，重污染企业的出口规模受到了抑制，不过我国的出口绿色化因此得到了提升。
After the reform and opening up, China‘s economy has achieved leapfrog development, but it has also paid a huge price in terms of the ecological environment. In recent years, with the proposal of "carbon peak" and "carbon neutrality" strategies and the need for high-quality economic development and industrial transformation and upgrading, green finance has become a hot research topic. The purpose of green finance is to guide the flow of funds, support the development of energy conservation, environmental protection, and clean industry, limit or eliminate backward production capacity, and promote the technological upgrading and industrial transformation of polluting enterprises. With the deterioration of the global ecological environment, the greenization of trade has become a consensus among most countries. With the world economy entering a downward period and China‘s exports showing weakness, how to effectively play the role of green finance as a policy tool and promote the improvement of China‘s export quality has become a very meaningful research issue.This paper aims to explore the impact of green finance policy on enterprise export scale and its mechanism through empirical research. Specifically, this paper takes the 2012 Green Credit Guidelines policy as a quasi-natural experiment, takes the A-share listed manufacturing companies from 2007 to 2016 as a sample, takes the overseas business income of listed companies as the explanatory variable, takes the difference-in-differences variable as the explanatory variable, and takes several characteristic variables reflecting the fundamentals of enterprises as the control variable to build a difference-in-differences model to explore the role of green finance policy on the export scale of enterprises. Then this paper divides the research sample into state-owned enterprises and non-state-owned enterprises, enterprises in eastern China, enterprises in central China, and enterprises in western China to analyze, and examines the heterogeneous impact of green finance policies on the export scale of each sub-sample. Finally, supported by the Porter effect theory, heterogeneous enterprise trade theory, and China‘s "export productivity" paradox theory, this paper explores the mechanism of the impact of green finance policy on enterprise export scale from the perspective of financial constraints and enterprise productivity.The research results indicate that: firstly, the 2012 "Green Credit Guidelines" policy have a significant inhibitory effect on the export scale of heavily polluting enterprises in A-share manufacturing listed companies. Secondly, the policy has no significant inhibitory effect on the export scale of state-owned enterprises among the heavily polluting enterprises in A-share manufacturing listed companies but has a significant inhibitory effect on non-state-owned enterprises. Thirdly, the policy has no significant inhibitory effect on heavily polluting enterprises in A-share manufacturing listed companies located in the western region of China, while it has a significant inhibitory effect on enterprises located in the central and eastern regions of China, with the most significant inhibitory effect on enterprises located in the central region.Through mechanism analysis, this paper confirms that financing constraints and enterprise productivity are the channels through which green finance policies affect the export scale of enterprises. The 2012 "Green Credit Guidelines" policy has a more significant inhibitory effect on the export scale of heavily polluting enterprises in A-share manufacturing listed companies with high financing constraints, and this policy has increased the productivity of heavily polluting enterprises in A-share manufacturing listed companies, which is conducive to technological progress and transformation and upgrading of enterprises. However, due to the existence of the "export-productivity" paradox in China, the export scale of heavily polluting enterprises has been suppressed, However, China‘s export greening has been improved as a result.
