基于能值改进模型的红米与烤烟作物系统可持续性评价——以贵州省盘州市为例

为准确测度农作物生产的可持续发展水平,进一步提高可持续发展能力。将碳排放与碳固定视为农田系统环境产出,纳入能值分析框架,建立能值改进指标,评价区域红米和烤烟2种不同作物生产模式的可持续性并进行灵敏性测试。研究发现,红米和烤烟系统的能值投入分别是1.26E+17sej/hm²和1.24E+17sej/hm²,产品能值产出分别是2.61E+16sej/hm²和6.55E+15sej/hm²,红米生产模式的产品产出效率较好。在环境能值产出方面,红米系统表现为净温室气体排放“源”,碳排放（5.97E+16sej/hm²）远大于碳固定（1.30E+15sej/hm²）,减排潜力较大;而烤烟系统则表现为碳固定盈余,碳排放（1.95E+14sej/hm²）小于碳固定（3.42E+14sej/hm²）。温室气体排放量变化对作物系统环境负载率和可持续发展水平的影响最大。结论表明,在传统能值分析体系中增设碳排放与碳固定指标可为农业系统可持续性评价提供更加全面的测算思路和方法借鉴。

Sustainability Evaluation of the Red Rice and Flue-Cured Tobacco Crop System Based on the Improved Emergy Model——A Case Study of Panzhou City,Guizhou Province

The goal of this study is to measure the sustainable development level of crop production, and to further improve the capacity of sustainable development. In the emergy analysis framework, carbon emission and carbon sequestration were considered as environmental outputs of the farmland system, and the emergy improvement index was created to evaluate the sustainability of two different crop production modes of red rice and flue-cured tobacco, as well as test its sensitivity. It was found that the emergy input of red rice and flue-cured tobacco system were 1.26E+17sej/ha and 1.24E+17sej/ha, respectively, and the product emergy output were 2.61E+16sej/ha and 6.55E+15sej/ha, respectively. The production pattern of red rice was better than flue-cured tobacco in the system product output efficiency. In terms of the environmental emergy output, the red rice system was source of net greenhouse gas emissions, it’s carbon emissions (5.97E+16sej/ha) were much more than carbon sequestration (1.30E+15sej/ha). There was great potential for emission reduction. The flue-cured tobacco system showed the carbon sequestration surplus, it’s carbon emissions (1.95E+14sej/ha) was less than carbon sequestration (3.42E+14sej/ha). The changes of greenhouse gas emissions had the greatest impact on the environmental load rate and sustainable development level of crop systems. This study showed that the addition of carbon emission and carbon sequestration indexes in the traditional emergy analysis system could provide more comprehensive calculation ideas and methods for the sustainability evaluation of agricultural production system.