基于县域尺度的湖南省农业碳排放时空特征分析

STUDY ON TEMPORAL AND APATIAL CHARACTERISTICS OF AGRICULTURAL CARBON EMISSIONS IN HUNAN PROVINCE AT COUNTY SCALE

关键词:  农业碳排放  碳源  时空特征  县域尺度  湖南

Key words:  agricultural carbon emissions  carbon source  temporal and spatial characteristics  county scale  Hunan province

摘要:

目的 全球各行业碳排放中，农业碳排放占比很大，对全球气候和生态环境的负面影响不可忽视，研究农业碳排放对实现农业节能减排有重要意义。方法 文章通过分析从农地利用过程碳排放、水稻种植过程甲烷排放、农地氧化亚氮排放和禽畜养殖过程碳排放四个方面碳源构建了农业碳排放测算清单，采用碳转化系数法测算出湖南省农业碳排放总量，并分析了2007—2017年湖南省农业碳排放的时空特征。结果 2007—2017年湖南省农业碳排放整体呈先上升后下降趋势，碳排放强度呈下降趋势，74.59%的县域单元的农业碳排放总量为负增长，94.26%的县域单元碳排放强度呈下降态势。湖南省各县（市、区）农业碳排放在空间布局上存在显著同质性，11年各县（市、区）空间均质性呈增强之势，空间异质性呈减弱之势。结论 对湖南省县域尺度农业碳排放不同维度时序特征的分析，有利于依此总结湖南省碳排放变化规律，预测未来农业碳排放走向，对县域农业碳排放空间布局研究有助于各地因地制宜，推行有差别的农业碳减排举措。

Abstract:

In the global carbon emissions of various industries, agricultural carbon emissions account for a large proportion, and the negative impact on the global climate and ecological environment cannot be ignored. Therefore, the research on agricultural carbon emissions is of great significance to achieve agricultural energy conservation and emission reduction. This paper constructed the measurement system of agricultural carbon emission from four aspects: carbon emission in the process of agricultural land use, methane emission during rice cultivation, nitrogen oxide emission from agricultural land and carbon emission from the process of raising livestock. And it quantitatively calculated the agricultural carbon emissions of 122 county units in Hunan province by the carbon conversion coefficient method, then analyzed the evolution characteristics of agricultural carbon emissions in Hunan province from the time dimension, and revealed the spatial distribution pattern and autocorrelation characteristics of agricultural carbon emissions in Hunan province from the spatial perspective. The results were showed as follows. (1) From 2007 to 2017, the overall agricultural carbon emissions of Hunan province increased first and then decreased, and the carbon emission intensity showed a downward trend. There were significant differences in the changes in the total agricultural carbon emissions of various counties (cities, districts) in Hunan province. The total agricultural carbon emissions of 74.59% of the county units showed a negative growth, and the carbon emission intensity of 94.26% of the county units showed a downward trend. (2) According to the spatial pattern of the total agricultural carbon emissions of each county (city, district) in 2017, the overall agricultural carbon emissions decreased from Dongting Lake District, Changsha-Zhuzhou-Xiangtan Urban Agglomeration and Hengyang City to the West and south. From 2007 to 2017, the agricultural carbon emissions of various counties (cities, districts) in Hunan province had significant homogeneity in the spatial layout. In the 11 years, the spatial homogeneity of the counties (cities, districts) had increased, and the spatial heterogeneity had been weakened. In general, the analysis of the temporal and spatial characteristics of different dimensions of agricultural carbon emission at county scale in Hunan province is helpful to summarize the change law of carbon emission, and predict the trend of agricultural carbon emission in the future. And to study on the spatial layout of agricultural carbon emission at county level will help localities adapt measures to local conditions and implement differentiated agricultural carbon emission reduction measures.