苏北沿海土地利用变化对土壤易氧化碳含量的影响  

Effects of land use change on soil readily oxidizable carbon in a coastal area of northern Jiangsu Province, East China

作　　者：王国兵[1] 赵小龙 王明慧[1] 阮宏华[1] 徐长柏 徐亚明 

机构地区：[1]南京林业大学,江苏省林业生态工程重点实验室,南京210037 [2]江苏省东台市林场,江苏东台224242

出　　处：《应用生态学报》2013年第4期921-926,共6页Chinese Journal of Applied Ecology

基　　金：国家林业公益性科研专项(200804006;201104006);江苏高校优势学科建设工程项目资助

摘　　要：土壤易氧化碳(readily oxidizable carbon,ROC)作为指示土壤有机碳(SOC)早期变化的敏感指标,对研究人类干扰及全球变化背景下的土壤有机碳库稳定性及其动态具有重要的指示意义.为深入了解土地利用变化对土壤易氧化碳含量的影响,本文对苏北沿海地区草地、农田、杨-农复合经营及杨树纯林4种不同土地利用方式的土壤ROC含量及其相关因子进行了测定.结果表明:苏北沿海地区不同土地利用类型的ROC含量表现为草地<农田<杨-农复合系统<杨树林,不同土地利用方式间ROC含量在0～10cm土层差异最为显著;ROC及ROC/SOC随着土层深度的增加而递减,且不同土层之间差异显著;4种土地利用方式ROC的季节变化趋势一致,其值均为夏季最大,冬季次之,春季最小;ROC与土壤pH值、土壤容重呈极显著负相关,与SOC、土壤水溶性有机碳(WSOC)、全N、土壤C/N、Mg呈显著或极显著正相关,而与土壤湿度、全P的相关性不显著.土地利用方式的变化显著影响了土壤易氧化碳的空间分布特征,土壤容重、pH值、全N和SOC是ROC在不同土地利用方式间产生差异的主要原因.Soil readily oxidizable carbon （ROC） is a sensitive index to indicate the early changes of soil organic carbon （ SOC）, and has important value to research the stability and dynamics of SOC pool under the backgrounds of human disturbance and global climate change. To further understand the effects of land use change on soil ROC, an investigation was conducted on the soil ROC content and related factors in four different land use types （grassland, farmland, poplar-agricuhure system and pure poplar plantation） in a coastal area of northern Jiangsu Province, East China. The soil ROC content was in the order of grassland 〈 farmland 〈 poplar-agriculture system 〈 pure poplar plantation, and the difference was most significant in 0-10 cm soil layer. The ROC and ROC/SOC ratio decreased with increasing soil depth, and had significant differences between different soil lay- ers in any one of the land use types. The soil ROC in the four different land use types had the same seasonal variation trend, with the maximum in summer, followed by in winter and autumn, and the minimum in spring. The soil ROC was significantly negatively correlated with soil pH and soil bulk density, positively correlated with SOC, soil water soluble organic carbon （WSOC）, total nitrogen （TN）, C/N ratio, and Mg, but less correlated with soil moisture and soil total phosphorus （TP）. The results indicated that land use change had significant effects on the spatial distribution charac- teristics of soil ROC, and soil bulk density, pH value, TN, and SOC were the main factors indu- cing the differences of soil ROC content between different land use types.

关 键 词：土地利用变化 易氧化碳 土壤理化性质 苏北沿海地区 

分 类 号：S153.6[农业科学—土壤学]