Divergent behaviour of soil nutrients imprinted by different land management practices in the Three Gorges Reservoir Area,China  

作　　者：Minxin Song Qiang Tang Chen Han Chuan Yuan Qingyuan Yang Jie Wei Xiubin He Xiheng Lv Adrian L.Collins 

机构地区：[1]Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station,School of Geographical Sciences,Southwest University,Chongqing,400715,China [2]Chongqing Observation and Research Station of Earth Surface Ecological Processes in the Three Gorges Reservoir Area,School of Geography and Tourism,Chongqing Normal University,Chongqing,401331,China [3]Key Laboratory of Mountain Surface Processes and Ecological Regulation,Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu,610299,China [4]Net Zero and Resilient Farming,Rothamsted Research,North Wyke,Okehampton,EX202SB,UK

出　　处：《International Soil and Water Conservation Research》2024年第4期896-907,共12页国际水土保持研究(英文)

基　　金：supported by the Science Fund for Distinguished Young Scholars of Chongqing(cstc2021jcyj-jqX0026);the Special Fund for Youth Team of Southwest University(SWU-XDJH202306);the Fundamental Research Funds for the Central Universities(SWU0200013);the National Natural Science Foundation of China(U2040207);funded by the UK Research and Innovation-Biotechnology and Biological Sciences Research Council(UKRI-BBSRC)via grant award BB/010961/1(Resilient Farming Futures)-specifically work package 2-BBS/E/RH/230004B;Detecting agroecosystem‘resilience’using novel data science methods.

摘　　要：Soil nutrients are essentially regulated by land management practices via modulating biotic element input and metabolism.The Three Gorges Reservoir Area in China was dominated by a farming landscape,but land management has become diversified over recent decades.How these restorative management practices may have affected soil nutrients is not completely understood.In this study,a space-time substitution approach was applied to evaluate soil nutrients and their stoichiometric changes in response to post-farming land management practices.Soil samples(0-10 cm,10-20 cm,and 20-40 cm)were collected from present-day croplands,cypress plantations,eucalyptus plantations,abandoned croplands,and citrus plantations.Soil organic matter,soil organic carbon,total nitrogen,alkaline hydrolyzed nitrogen,total phosphorus,and available phosphorus were determined.The results showed that soil organic matter and total nitrogen in abandoned croplands,cypress plantations,eucalyptus plantations and citrus plantations were increased by 186%and 190%,184%and 107%,45%and 33%,45%and 54%,respectively,in comparison with those of present-day croplands.Soil nutrients except for total phosphorus decreased with soil depth by exclusion of tillage mixing.Comprehensive soil nutrient index showed that abandoned croplands(0.90)and cypress plantations(0.72)exhibited favorable nutrient recovery capacity.Soil C:P and N:P ratios increased in abandoned croplands,cypress plantations,and eucalyptus plantations.Phosphorus may become a limiting factor for plant growth with prolonged recovery in abandoned croplands,cypress plantations,and eucalyptus plantations,while soil organic matter and total nitrogen deficiencies were exacerbated in citrus plantations and present-day croplands.Therefore,cropland abandonment and reforestation(particularly cypress trees plantation)are recommended options for restoring soil nutrients in the Three Gorges Reservoir Area.

关 键 词：REFORESTATION Cropland abandonment Land use conversion Space-time substitution approach 

分 类 号：S15[农业科学—土壤学]