1980-2010年安徽省土壤有机碳密度及储量时空变化分析

利用安徽省第二次土壤普查资料和2010-2011年土壤调查数据,运用GIS技术,研究1980-2010年安徽省表层（0~20 cm）和1 m土体中土壤有机碳（SOC）密度和储量的时空变化,并探讨土地利用变化对SOC储量变化的影响。研究表明：① 1980-2010年安徽省表层和1 m土体中SOC密度平均减少0.37 kg/m²和1.63 kg/m²,但耕地的SOC密度增加。② 1980-2010年,全省SOC密度空间变化呈现北增南减的趋势,且增加幅度由北向南依次减小。表层和1 m土体的SOC密度增加的面积为56.97%和58.21%。③ 1980-2010年,全省表层SOC储量减少34.23×10⁹ kg,1 m土体中SOC储量减少197.26×10⁹ kg。淮北平原、江淮丘陵岗地和沿江平原的SOC储量增加,皖西大别山区和皖南丘陵山区减少。④ 非耕地转换为耕地,比保持用地类型不变或变为其他非耕地类型,SOC密度和储量减少较慢。耕地类型内部转换（水田和旱地间转换）比保持类型不变的SOC密度和储量增加较多。研究成果为区域土壤固碳潜力、土壤肥力变化等研究提供科学依据。

Spatial-temporal change of soil organic carbon density and storage in Anhui province from 1980 to 2010

In this paper, Anhui province was selected as a subject for a case study. A comparative study was conducted based on the data of the Second National Soil Survey and the data collected during 2010 and 2011. The study, applying GIS spatial analysis, focuses on the spatial-temporal change of soil organic carbon (SOC) density and storage in the surface layer (0-20 cm) and 0-100 cm layer of the study area during the period (1980-2010). Furthermore, this research explored the impact of land use change on SOC density and storage. The results are as follows: (1) From 1980 to 2010, the mean SOC density decreased by 0.37 kg/m² in the surface layer, and by 1.63 kg/m² in the 0-100 cm layer in the whole province. SOC density in the cultivated land increased, yet it decreased in the non-cultivated land. (2) The map of SOC density change showed that SOC density increased in the north and decreased in the south. The increment rate decreased from north to south within the province. The area with SOC density increment was slightly more than the area where SOC density decreased. (3) From 1980 to 2010, SOC storage decreased by 34.23×10⁹ kg and 197.26×10⁹ kg in the surface layer and 0-100 cm layer, respectively. SOC storage increased in Huaibei plain, Jianghuai hilly land and Yangtze plain, and decreased in western and southern hilly mountains. (4) SOC density and storage reduction is relatively slow in the context of non-cultivated land changing to cultivated land, rather than in the remaining original land functions or transferring to other non-cultivated functions. The internal transfer of cultivated land functions, i.e., changing to paddy field or upland, will result in more increment in SOC density and storage than the land with the remaining functions. The research will provide support in decision making related to regional soil carbon sequestration potential and soil fertility changes.