基于碳汇功能的粮食作物生态补偿机制研究——以小麦、玉米为例

This study aims to estimate the carbon sink function of alimentarn crops and then design ecological compensation system on this basis. Firstly, the carbon sink and the carbon source of unit area alimentarn crop, mainly wheat and maize, are estimated separately. Then carbon sink function minus carbon source function and we can get net carbon sink function of unit area alimentarn crop, which is the basis for the compensation criteria. Secondly, the ecological compensation system of alimentarn crops is designed according the first stage of the study. Thirdly, alimentarn low-carbon cultivation ecological compensation mechanism is designed. Low-carbon cultivation includes reduction of chemical input, low-carbon tillage modes and straw returning. The compensation criteria are studied under the premise of no falling of farmers’ income. Forthly, suggestions to improve alimentarn carbon sink compensation mechanisms are put forward, including improving relative laws and regulations, establishment of systems like fund and institution safeguard, and research and development of low-carbon techniques. This study provides theoretical basis for alimentarn crop carbon sink ecological compensation system, as well as systematical and practical theoretical guidance for alimentarn crop carbon sink ecological compensation in our country. It answers the question of “how we should maintain the market compensation mode of alimentarn crop carbon sink compensation from legal and systematical level” and provides suggestions and references for the improvement of carbon trade mechanism as well as policy-making activities in agricultural ecological compensation, especially carbon sink compensation. It helps to promote green and ecological alimentarn production in our country.

本研究拟对粮食作物的净碳汇进行计量，并据此设计碳汇补偿机制。首先，从投入要素、生产过程等方面对单位面积粮食作物（分小麦、玉米）的碳源进行核算，同时对粮食作物生长过程中的碳汇进行计量，综合计算粮食作物净碳汇（碳汇减去碳源），作为补偿依据；其次，根据粮食作物碳汇功能，构建粮食作物碳汇补偿机制；再次，对化肥农药使用减量化、采用低碳耕作模式以及实施秸秆还田等低碳粮食生产模式，研究其补偿标准，以鼓励农户的低碳粮食种植；最后，构建资金、立法、制度等保障机制，以保障粮食作物碳汇补偿机制的顺利实施。本研究为粮食作物碳汇生态补偿机制构建提供理论依据，为我国粮食作物碳汇生态补偿提供系统、实用的理论指导，回答“如何在法律、制度层面上保障粮食作物碳汇市场补偿”的问题，为我国的农业生态补偿，尤其是碳汇补偿政策的制定和碳交易机制的完善提供建议和借鉴，最终推动我国绿色、生态粮食生产的发展。

随着我国自愿减排的压力增大，国内碳排放权交易机制的完善和发展越来越紧迫。由于森林碳汇项目已经得到较多的开发，农作物，尤其是粮食作物的碳汇项目和碳汇生态补偿的潜力巨大。在此背景下，本项目从粮食作物碳汇功能估测的技术和粮食作物碳汇生态补偿、碳汇j交易项目的政策机制设计两方面展开研究：对粮食作物碳源、汇计量范围、计量方法、数据采集方法进行了全面分析和界定。以山东省小麦-玉米轮作农田生态系统为例，选择山东省济宁市兖州区粮食主产区作为试验区，采集了小麦、玉米碳源、碳汇影响因子数据，并基于有机碳动态模型，模拟了农田有机碳动态变化，设计出小麦碳汇估算与可视化系统，解决了估算农田土壤有机碳含量缺少大量连续数据、模型存在一定局限性、农田土壤有机碳信息的智能化管理研究较少和数据采集困难等问题，可以提高农田土壤有机碳含量的估算精度。在政策机制设计方面，进一步界定粮食作物净碳汇功能和净碳汇生态补偿的概念、理论基础、受偿与补偿主体、补偿原则、标准、方式等问题。并展开粮食作物低碳种植模式的碳汇补偿机制设计，从三种低碳种植模式：化学品减量投入、低碳耕作和秸秆还田的角度探讨补偿主客体、补偿标准计算及补偿方式设计，对市场补偿方式进行探讨。在补偿标准方面，考虑不同类型的碳抵消量需要接受不同程度的折扣，形成不同的价格。还考察了粮农进行低碳种植的受偿意愿。基于山东省小麦-玉米轮作种植农户的调查数据，受访农户采用深松技术后，农机作业成本增加，但小麦产量增长，调查区小麦-玉米轮作种植户的净收益可达到48元/亩，为低碳种植的生态补偿标准的设立提供了参考。本研究从估测技术和补偿机制两方面入手，有助于我国农业碳汇项目和低碳农业耕作的推进和开展，有利于进一步完善我国碳交易机制，增加碳信用的供给方式，增加粮农收入，最终推动我国绿色、生态粮食生产的发展。