Changes in profile distribution and chemical properties of natural nanoparticles in paddy soils as affected by long-term rice cultivation  

作　　者：Dan HUANG Xinyu ZHU Baile XU Yan HE Mingkui ZHANG Fei LIU Zhenghua LIAN Randy ADAHLGREN Philip CBROOKES Jianming XU 

机构地区：[1]Institute of Soil and Water Resources and Environmental Science,College of Environmental and Resource Sciences,Zhejiang University,Hangzhou 310058(China) [2]Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment,Hangzhou 310058(China) [3]Department of Land,Air and Water Resources,University of California-Davis,Davis CA 95616(USA)

出　　处：《Pedosphere》2021年第5期659-669,共11页土壤圈（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.41721001 and 41130532)。

摘　　要：Systematic studies on the genesis,properties,and distribution of natural nanoparticles(NNPs)in soil remain scarce.This study examined a soil chronosequence of continuous paddy field land use for periods ranging from 0 to 1000 years to determine how NNPs in soil changed at the early stages of soil genesis in eastern China.Soil samples were collected from coastal reclaimed paddy fields that were cultivated for 0,50,100,300,700,and 1000 years.Natural nanoparticles were isolated and characterized along with bulk soil samples(<2-mm fraction)for selected physical and chemical properties.The NNP content increased with increasing soil cultivation age at 60 g m^(-2) year-1,which was related to decreasing soil electrical conductivity(172-1297μS cm^(-1))and NNP zeta potentials(from -22 to -36 mV)with increasing soil cultivation age.Changes in several NNP properties,such as pedogenic iron oxide and total organic carbon contents,were consistent with those of the bulk soils across the soil chronosequence.Notably,changes in NNP iron oxide content were obvious and illustrated active chemical weathering,pedogenesis,and potential impacts on the microbial community.Redundancy analysis demonstrated that the soil cultivation age was the most important factor affecting NNP properties,contributing 60.7% of the total variation.Cluster and principal component analysis(PCA)revealed splitting of NNP samples into age groups of 50-300 and 700-1000 years,indicating rapid evolution of NNP properties,after an initial period of desalinization(approximately 50 years).Overall,this study provides new insights into NNP evolution in soil during pedogenesis and predicting their influences on agriculture and ecological risks over millennial-scale rice cultivation.

关 键 词：natural nanoparticle evolution soil chronosequence soil cultivation age soil genesis soil nanoparticles 

分 类 号：S511[农业科学—作物学]