摘要
土壤有机碳是土壤养分和质量评估的重要指标之一,在小流域尺度上,研究土壤有机碳(SOC)含量水平和垂向的分布特征及其主要影响因素对土地利用的科学管理具有重要意义。以粤北英德市鹿颈水库小流域为研究对象,通过采集流域内茶园(英红12号和英红9号)、桉树林、马尾松林和次生林等4种主要土地利用类型的土壤,测定土壤的粒度组成、土壤容重(BD)、pH、电导率(EC)、SOC、颗粒有机碳(POC)、全氮(TN)、碳氮比(C/N),以及土壤的δ13C和δ15N,结合采样点的坡度、坡向以及凋落物的质量和厚度,采用冗余分析研究SOC和POC含量的主要影响因素。结果表明:1)鹿颈水库流域土壤pH在4.2~5.8之间,出现土壤酸化现象,土壤质地均为粉壤土,不同土地利用类型之间土壤pH、EC、TN含量、C/N及δ13C、δ15N差异显著(P<0.05);2)在0~40 cm的土壤深度,SOC和POC含量均随深度的增加而降低,变化范围分别为0.5%~1.3%和1.2~3.9 g/kg,表现出明显的表聚性,但不同土地利用类型之间SOC和POC含量没有明显差异;3)本研究所选取的土壤因子、地形因子和环境因子可以解释SOC和POC含量78.1%的变异,其中土壤因子中的C/N、TN含量、pH、土层深度和BD是影响水库流域SOC和POC含量变化的主要因素,SOC和POC含量与C/N、TN含量呈显著正相关,而与土壤pH、土层深度和BD呈显著负相关。
Soil organic carbon is one of the important indicators for soil nutrient and quality assess‐ment.At the small watershed scale,studying the horizontal and vertical distribution characteristics of soil organic carbon and its main influencing factors is of great significance to the scientific managemen of landuse.Taking the small watershed of Lujing Reservoir in Yingde city,northern Guangdong Province as the research object,collecting soils of four main landuse types including Camellia sinensis gardens(Yinghong12(Cs12)and Yinghong9(Cs9)),Eucalyptus robusta forests(Er),Pinus massoniana forests(Pm)and secondary forests(SF)in the watershed.Soil particle size composition,pH,electrical conduc‐tivity(EC),soil organic carbon(SOC),particulate organic carbon(POC),total nitrogen(TN),carbon to nitrogen ratio(C/N),and soil carbon and nitrogen isotope values(δ13C,δ15N)were measured,combined with the slope and aspect of the sampling site and the quality and thickness of litter,redundant analysis was conducted to explore the main influencing factors of SOC and POC content.The results show that1)The soil pH in the Lujing Reservoir watershed is between 4.2 and 5.8,and soil acidification occurs The soil texture is silt loamy.The difference in soil pH,EC,TN,T/N,andδ13C,δ15N between differen landuse types is significant(P<0.05);2)In 0~40 cm depth,the SOC and POC content decrease with the increase of the depth,and the variation ranges are 0.5%~1.3%and 1.2~3.9 g/kg,respectively,showing obvious surface aggregation.However,there is no significant difference in SOC and POC conten between the different landuse types selected;3)The soil,topographic and environmental factors selected in this study can explain 78.1%of the variation of SOC and POC.Among them,C/N,TN,pH,soi depth and bulk density(BD)are the main factors affecting the changes in SOC and POC content in this small watershed.SOC and POC were significantly positively correlated with C/N and TN,while signifi‐cantly negatively correlated with soil pH,soil depth,and BD.
作者
王蝶
江涛
禤映雪
黎坤
梁作兵
黄颖
WANG Die;JIANG Tao;XUAN Yingxue;LI Kun;LIANG Zuobing;HUANG Ying(School of Geography and Planning,Sun Yat-sen University,Guangzhou 510006,China;School of Environmental Science and Engineering,Sun Yat-sen University,Guangzhou 510006,China)
出处
《中山大学学报（自然科学版）（中英文）》
CAS
CSCD
北大核心
2023年第1期75-85,共11页
Acta Scientiarum Naturalium Universitatis Sunyatseni
基金
中国博士后科学基金(2021M693588)
国家自然科学基金(41961144027)
广西岩溶动力学重大科技创新基地开放课题(KDL&Guangxi202105)。
关键词
土壤有机碳
土地利用类型
碳氮同位素
冗余分析
鹿颈水库流域
soil organic carbon
landuse types
carbon and nitrogen isotope
redundancy analysis
Lujing reservoir watershed
