中国土壤与肥料Issue(6)：38-46,9.DOI:10.11838/sfsc.1673-6257.24584
亚热带低丘侵蚀-沉积连续地形中土壤有机碳、氮和磷的微域分布特征
Micro-domain distribution of soil organic carbon,nitrogen and phosphorus in an erosion-sedimentary continuum in subtropical hilly area
摘要
Abstract
To understand the characteristics of micro-domain differentiation of organic carbon(C),nitrogen(N)and phosphorus(P)in low hilly area in South China,a typical gentle slope land in the red sandstone low hilly with coverage of shrub was selected in the central and western region of Zhejiang province.Profile samples from different topographic locations including top slope,middle slope,down slope and piedmont were collected and analysed,the content and vertical distribution of organic C,particulate organic C,microbial biomass C,total N,alkali-hydrolyzed N,total P and available P in the soils from different topography were characterized,and the effects of microtopography on the spatial distribution of soil organic C,N and P in the low hilly and sloping land were studied.The results showed that there were significant differences in soil mechanical composition among different topographic locations.The clay and silt contents were the highest in the piedmont,the next was the down slopes,and the clay and silt contents were the lowest in the middle slopes.The contents of soil organic C,particulate organic C,microbial biomass C,total N,alkali-hydrolyzed N and total P decresed in the order of piedmont>down slope>top slope>middle slope.The storage of organic C in 0-40 cm soil layer in piedmont and down slope was 4.08 and 2.69 times of that in the middle slope,3.38 and 2.23 times of that in the top slope,respectively.The storage of total N in piedmont and down slope was 3.10 and 2.05 times of that in the middle slope,and 2.79 and 1.84 times of that in the top slope.The effect of slope positions on P storage was relatively small.The P storage in piedmont and down slope was 1.28 and 1.24 times of that in middle slope,and 1.31 and 1.26 times of that in top slope,respectively.The contents of soil organic C,particulate organic C and total N in both top slope and middle slope decreased obviously from the topsoil to the bottom,while those in both the piedmont and down slope decreased slowly with the depth.There were higher organic C and total N in the deeper soil layer in both piedmont and down slope,but the vertical distribution of total P for all locations was relatively consistent.The difference of soil organic C,particulate organic C and total N between piedmont,down slope and top slope,moddle slope increased with the depth of profile.The above patterns of organic C and total N had obvious erosion-deposition characteristics,that was,the top and middle slope were erosion areas where the organic C and N were mainly concentrated in the topsoil.The piedmont and down slope were sedimentary areas where organic C and total N could be accumulated in the whole profile.The positive terrain located at the higher part of the terrain was the source of the matter and energy in the key zone,while the negative terrain located at the lower part was the concentration(sink)of the matter and energy in the key zone.The erosion-deposition process made the carbon lost from the erosion area become an important"C source"in the sedimentary area.关键词
坡面侵蚀/微地形/有机碳/全氮/全磷/侵蚀-沉积/碳源/碳汇Key words
slope erosion/microtopography/organic carbon,total nitrogen,total phosphorus/erosion-deposition/carbon source/carbon sink引用本文复制引用
谢小聪,徐欣欣,施黎云,包日在,章明奎..亚热带低丘侵蚀-沉积连续地形中土壤有机碳、氮和磷的微域分布特征[J].中国土壤与肥料,2025,(6):38-46,9.基金项目
国家自然科学基金面上项目(42271047). （42271047）
