开封市不同功能区城市土壤有机碳含量与密度分析

Contents and Densities of Soil Organic Carbon in Urban Soils in Different Function Areas of Kaifeng

研究开封城市土壤有机碳，发现不同功能区类型间及城区与郊区间的有机碳特性存在差异：土壤表层有机碳含量为工业区〉休闲区〉交通区〉文教区〉行政／居民区；表层有机碳密度为休闲区〉工业区〉交通区〉文教〉行政／居民区；土壤剖面有机碳密度为文教区〉交通区〉工业区〉休闲区〉行政／居民区。城市土壤表层有机碳密度和剖面有机碳密度均沿城郊剖面线呈下降式梯度变化，城区分别是郊区的2．53和1．56倍。城市土壤有机碳积累主要在地表之下0—30cm范围内。

Urban soil, a special soil type, forming along with the development of city, has unique properties of soil organic carbon. On the basis of field investigation and laboratory analysis, the soil organic carbon （SOC）of Kaifeng City, Henan Province was studied, and the results showed that the characteristics of SOC were different not only among function districts in urban area, but also between urban area and suburb. The contents of SOC in topsoil followed the order of industrial district 〉 recreational district 〉 traffic district 〉 cultural and educational district 〉 administrative and residential district. The orders of densities of soil organic carbon（SOCD） in topsoil and profile were recreational district 〉 industrial district 〉 traffic district 〉 cultural and educational district 〉 administrative and residential district, and cultural and educational district 〉 traffic district 〉 industrial district 〉 recreational district 〉 administrative and residential district, respectively. SOCD in topsoil and profile decreased along the transection line from urban area to suburb, and urban area had 2.53-fold more SOCD in topsoil and 1.56-fold more SOCD in profile than suburb, respectively. SOC decreased with the depth and was mainly distributed within the scope of 0-30 cm.