中国南方喀斯特石漠化演替过程中土壤有机碳的响应及其影响因素分析  

Response of soil organic carbon to rocky desertification succession in south China karst and the analysis of its influence factors

作　　者：王霖娇[1,2] 盛茂银[1] 李瑞 

机构地区：[1]贵州师范大学喀斯特研究院,贵阳550001 [2]贵州师范大学职业技术学院,贵阳550025 [3]贵州省水土保持监测站,贵阳550002

出　　处：《生态科学》2016年第1期47-55,共9页Ecological Science

基　　金：贵州省社会发展攻关计划课题(黔科合SZ[2014]3036号);国家水利部公益性行业科研专项经费项目(201401050);贵州省水利厅科技项目(KT201409);贵州师范大学博士科研启动基金(2012)

摘　　要：以中国南方典型喀斯特石漠化生态系统土壤为研究对象,运用野外定点取样和实验室分析检测方法,研究喀斯特石漠化生态系统土壤有机碳分布特征及其影响因素;运用空间代替时间方法,探讨石漠化演替过程中土壤有机碳的响应及其机制,旨在为中国南方喀斯特森林生态保护和石漠化生态系统恢复重建提供理论支撑。结果表明:1)喀斯特石漠化生态系统土壤有机碳含量较低,三个研究区平均值分别为23.42、25.78和26.03 g·kg–1;2)不同等级石漠化环境土壤有机碳含量存在显著差异,但土壤有机碳含量并不是随着石漠化程度增加而一直降低,而是一个先降低后增加的趋势;3)土壤有机碳与土壤特性有明显的相关性,与土壤总氮、水解氮、速效钾、总孔隙度、自然含水量、毛管持水量、田间持水量和上层渗透性存在极显著地正相关,与总磷、下层渗透性存在显著地正相关,与容重存在极显著地负相关,而与p H、总钾、有效磷、土壤呼吸、毛管孔隙度、非毛管孔隙度无明显相关性;4)土地覆被变化明显影响石漠化生态系统土壤有机碳含量,而地貌的影响不明显。研究结果不仅对中国南方喀斯特森林生态保护和石漠化生态系统恢复重建具有重要的意义,而且对应对全球变化碳循环的减源增汇同样具有重要的科学价值。In this study, three typical karst rocky desertification regions, Yachi, Hongfenghu, and Huajiang of Guizhou Province, representing three typical karst landforms of plateau mountain, plateau basin, and plateau gorge respectively, were selected as experiment areas. Then, the soil organic carbon（SOC） was surveyed and analyzed by the methods of chemical determination and mathematical statistics. Results are as follows. 1）The SOC content of karst rocky desertification ecosystem is low, and the average SOC content of the three experiment sites studied is 23.42, 25.78 and 26.03 g·kg-1, respectively. 2） There are obvious differences of SOC content in different degrees of rocky desertification. But, not as expected, the SOC content does not always decrease with the increased degree of rocky desertification. In fact, with the increased degree of rocky desertification, the SOC content firstly decreases and then increases. 3） There are significant correlations between SOC content and other soil properties studied. The SOC content is extremely significant and positive correlation with soil total nitrogen content, hydrolysis nitrogen content, available potassium content, total porosity, natural moisture capacity, capillary moisture capacity, field moisture capacity, and upper strata saturated permeability, significant and positive correlation with soil total phosphorus content and lower strata saturated permeability, and extremely significant and negative correlation with soil bulk density. 4） The effect of land use and land cover change（LUCC） on SOC content in karst rocky desertification ecosystem is significant, and the effect of landform on SOC content is not obvious. Results have important values in the protection of karst forest ecosystem, the control of rocky desertification, and the scientific management for carbon cycle.

关 键 词：喀斯特 石漠化 土壤有机碳 演变规律 机制 

分 类 号：P94[天文地球—自然地理学]