摘要
明确周期性淹水-出露条件下消落带土壤碳(C)、氮(N)、磷(P)及其生态化学计量沿水位高程垂直分异特征,有利于该地区的土壤养分评估及管理。通过三峡水库典型土质消落带不同水位高程土壤的采样分析,探讨不同水位高程土壤C、N、P生态化学计量特征及其影响因素。结果表明:(1)消落带土壤有机碳(SOC)、全氮(TN)、全磷(TP)平均值分别为8.70、0.79、0.63 g/kg,均低于未淹水样地。随水位高程增加,土壤SOC、TN含量增加,TP含量减少。(2)土壤C/N、C/P、N/P平均值分别为11.67、15.37、1.47,其中C/N、C/P高于未淹水样地,N/P低于未淹水样地。随着水位高程增加,土壤C/N降低,C/P、N/P增加。土壤C、N、P之间存在较好的耦合关系,N可能是该地区的土壤限制性元素,存在硝酸盐淋溶风险。(3)Pearson相关性分析说明土壤理化性质会显著影响土壤C、N、P含量(P<0.05),进而调控其生态化学计量特征,其中土壤pH、容重、水稳性团聚体组成是主要影响因子,其次是土壤含水率和粒径组成。综上,周期性淹水过程影响消落带土壤C、N、P含量及其生态化学计量特征,今后应根据消落带土壤C、N、P生态化学计量特征的空间异质性,采取具有养分适应性的水土保持林草措施配置。
Clarifying the vertical differentiation characteristics of soil carbon(C),nitrogen(N),phosphorus(P),and their ecological stoichiometry along the water level elevation under the periodic flooding-emergence conditions is beneficial to the soil nutrient management in the water level fluctuation zone(WLFZ).In this study,the typical riparian zone of the Three Gorges Reservoir was taken as the research area.Soil samples were collected at depths of 0-10,10-20,and 20-30 cm at water level elevations of 145-155,155-165,and 165-175 m,with the unflooded grassland at elevation of 180 m as the upper limit.Soil organic carbon(SOC),total nitrogen(TN),total phosphorus(TP),pH,soil bulk density(SBD),soil water content(SWC),soil mechanical composition,and agglomerates were analyzed.The purposes of this study was to explore the ecological stoichiometric characteristics of soil C,N,and P at different water level elevations and soil layers and to identify the influencing factors.The results showed that:(1)Change of water level elevation affected the soil C,N,and P contents.The mean values of SOC,TN,and TP in the WLFZ were 8.70,0.79,and 0.63 g/kg,respectively,which were lower than those in the unsubmerged area.With the increase of water elevation,the soil SOC and TN contents increased,and TP content decreased,and the nutrient contents of the surface soil were higher than those of other soil layers.(2)The mean values of soil C/N,C/P,and N/P were 11.67,15.37,and 1.47,respectively,where C/N and C/P were higher than those of the unsubmerged area and N/P was lower than that of the unsubmerged area.As the water level elevation increased,soil C/N decreased and C/P and N/P increased.There existed a good coupling relationship between soil C,N and P.Nitrogen might be the limiting soil element in the WLFZ,and there was a risk of nitrate leaching.(3)Correlation analysis showed that soil physicochemical properties significantly affected the contents of soil C,N and P(P<0.05),thus regulating the ecological stoichiometric characteristics.Of all the in
作者
禹妍彤
鲍玉海
吕佼容
谢航宇
张浩哲
贺秀斌
YU Yan-tong;BAO Yu-hai;LV Jiao-rong;XIE Hang-yu;ZHANG Hao-zhe;HE Xiu-bin(Key Laboratory of Mountain Surface Processes and Ecological Regulation,Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610299,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《长江流域资源与环境》
CAS
CSCD
北大核心
2023年第12期2558-2567,共10页
Resources and Environment in the Yangtze Basin
基金
国家自然科学基金长江水科学研究联合基金(U2040207)
四川省科技计划重点研发项目(2022YFS0471)
国家自然科学基金面上项目(41977075)。
关键词
消落带
水位高程
土壤养分
生态化学计量学
三峡水库
water level fluctuation zone
water level elevation
soil nutrition
ecological stoichiometry
Three Gorges Reservoir
