Effects of climate,soil and water source on determining exchangeable copper concentration in lowland paddy fields in Sri Lanka  

作　　者：Charuka Chandrasekara Mojith Ariyaratne Ranga Madushan Upul Rathnayake Rohana Thilakasiri Harsha Kadupitiya Rohana Chandrajith Chalinda Beneragama Lalith Suriyagoda 

机构地区：[1]Department of Crop Science,Faculty of Agriculture,University of Peradeniya,Peradeniya 20400,Sri Lanka [2]Rice Research and Development Institute,Department of Agriculture,Peradeniya,20400,Sri Lanka [3]Natural Resources Management Centre,Department of Agriculture,Peradeniya,20400,Sri Lanka [4]Department of Geology,Faculty of Science,University of Peradeniya,Peradeniya,20400,Sri Lanka

出　　处：《Circular Agricultural Systems》2024年第1期76-84,共9页循环农业系统（英文）

基　　金：supported by the World Bank under the Accelerating Higher Education Expansion and Development Grant(AHEAD)(Grant No.AHEAD/RA3/DOR/AGRI/PERA-No16).

摘　　要：Copper(Cu)is an essential micronutrient for rice.However,the current status of Cu in Sri Lankan paddy soils is not known.Therefore,the current study was conducted to determine the distribution of exchangeable Cu concentration and examine the interactive effects of the agro-climatic zone(ACZ),soil order,and water source in determining the exchangeable Cu concentration in lowland paddy fields in Sri Lanka.A total of 7,544 soil samples representing six ACZs,six soil orders,and three water sources were collected using a stratified random sampling approach.Soil exchangeable Cu fraction was extracted in 0.01 M CaCl_(2)and measured using Inductively Coupled Plasma Mass Spectrophotometry.Exchangeable Cu concentration was in the range of 0.04−728μg·kg^(−1)with a mean value of 62.4μg·kg^(−1).Only 5%of the soil samples tested had Cu concentration greater than 200μg·kg^(−1)indicating a widespread Cu deficiency in Sri Lankan paddy fields(i.e.critical level causing Cu deficiency;200-300μg·kg^(−1)).Among the climatic zones Wet zone had higher and the Dry zone had lower Cu concentrations.Among the soil orders,histosols had higher and alfisols had lower Cu concentrations.Water sources used for rice cultivation did not determine Cu concentration.Moreover,Cu concentration was positively correlated with soil pH.As most of the soil samples were deficient in soil exchangeable Cu,spatial maps generated in the current work could be used to develop ACZ and soil order-specific agronomic and management strategies to improve soil Cu fertility status.

关 键 词：SOIL PADDY FERTILITY 

分 类 号：S15[农业科学—土壤学]