摘要
茂兰原生林中20m×30m研究样地存在着7类小生境：石面、土面、石土面、石沟、石缝、石坑、石洞。样地内土壤有机碳的含量范围为40.1～203.5gkg^-1,样点与小生境间土壤有机碳含量的变异系数分别为43%和41%;同类型小生境间为22%～42%;小生境内为14%～57%;说明样地内土壤有机碳含量具有高度的空间变异性。为了促进岩溶山区土壤退化研究中数据之间的可比性,文中建议以土壤面积权重确定的小生境土样组成样地代表性土样的方法。选取样地内面积之和超过样地总土壤面积95%以上的几类小生境,由面积权重确定组成样地土壤代表样的各类小生境土样样品量,而各类小生境土样则分别由以面积权重确定的同类小生境样品量混合构成。利用该方法计算的研究样地土壤有机碳含量的面积权重值为92.1gkg^-1。
A plot （20 m × 30 m） was delineated for study in the Maolan karst virgin forest, containing 7 types of microhabitats- rocky surface, soil surface, rocky soil surface, rocky gullies, rocky crevices, stone pits and stone caves. The soil organic carbon （SOC） contents in the plot ranged from 40.1 g kg^- 1 to 203.5 g kg^- 1. The variation coefficients of SOC contents of the plot and the microhabitats were 43% and 41%, respectively, 22% ～ 42% between microhabitats of the same, and 14% ～ 57 % within a microhabitat, suggesting high spatial variation of the SOC contents in the plot. In order to improve comparability of the data available for the study of soil degradation in the karst ecosystem, a representative sampling method is advanced for collecting samples in a sampling site formed of sampling points of the same microhabitat, which is delineated based on soil area weight. It goes like this： select several types of microhabitats whose respective sum of land areas exceeds 95 % of the total soil area of the sample plot, determine quantity of the soil sample of each microhabitat that forms the representative soil sample of the plot by area weight, and the soil sample of each selected microhabitat is mixed out of soil samples from land patches of the same type of microhabitat, and their quantities are determined by area weight. Using this method, the surface area-weighted value of the SOC content in this plot was figured out to be 92.1 g kg^-1.
出处
《土壤学报》
CAS
CSCD
北大核心
2007年第3期475-483,共9页
Acta Pedologica Sinica
基金
中国科学院创新团队国际合作伙伴计划
科技支黔工程项目
知识创新前沿领域项目资助
关键词
土壤有机碳
空间变异性
代表性土样
喀斯特
原始森林
茂兰
Soil organic carbon
Spatial variability
Representative soil sample
Karst
Virgin forest
Maolan
