轮作对设施蔬菜大棚中次生盐渍化土壤盐分离子累积的影响  

Effect of crop rotation on ion accumulation in secondary salinization soil of vegetable field in greenhouse

作　　者：施毅超[1] 胡正义[1,2] 龙为国[3] 夏旭[2] 朱春游[1] 巴玉鑫[1] 赵言文[3] 

机构地区：[1]中国科学院研究生院资源与环境学院,北京100049 [2]中国科学院南京土壤研究所,南京210008 [3]南京农业大学资源与环境学院,南京210095

出　　处：《中国生态农业学报》2011年第3期548-553,共6页Chinese Journal of Eco-Agriculture

基　　金：中国科学院知识创新工程项目(KSCX2-YW-N-038)资助

摘　　要：2007年8月在江苏省宜兴市采集10个典型大棚土壤及其邻近露地蔬菜地土壤调查其离子组成和电导率,并选择2个土壤具有次生盐渍化特征的大棚研究轮作(蓖麻-白菜-蓖麻、辣椒-白菜-辣椒)对土壤电导率(EC)和离子组成的影响。结果表明,大棚蔬菜地土壤EC显著高于露地蔬菜地土壤,20%的大棚土壤已发生次生盐渍化(EC>500μS.cm-1);大棚土壤的SO42-、NO3-离子浓度显著高于露地蔬菜土壤,说明SO42-、NO3-是影响大棚次生盐渍化的主要离子。2年3茬大棚蔬菜地轮作试验结果表明,蓖麻-白菜-蓖麻轮作导致土壤EC下降5%,辣椒-白菜-辣椒轮作使土壤EC下降33%,表明后者对土壤次生盐渍化改良效果优于前者。两轮作系统盐分离子累积差异主要在于SO42-,辣椒-白菜-辣椒轮作能降低土壤SO42-的累积,而蓖麻-白菜-蓖麻轮作则不然。建议根据次生盐渍化土壤主控盐分离子以及不同作物对盐分离子吸收累积偏向性选择合适的轮作系统,实现轮作改良次生盐渍化最佳效果。Soil samples from ten plastic greenhouse vegetable fields（PGVF） and another ten soil samples from open vegetable fields（OVF） were collected in Aug.2007 in Yixing City,Jiangsu Province.The soils were analyzed and compared for soil ion accumulation and soil electrical conductivity（EC）.Two PGVFs with secondary salinization soil were selected to compare two crop rotation systems（CCC： castor-Chinese cabbage-castor;PCP： pepper-Chinese cabbage-pepper） for EC and ion accumulation.The study showed higher soil EC under PGVF（average of 433 μS·cm？1） compared with OVF（178 μS·cm？1）.About 20% of the samples was detected with secondary salinization for EC 500 μS·cm？1 under PGVF.SO42？ and NO3？ anions were statistically higher in PGVF than in OVF.This implied that SO42？ and NO3？ were the main ions controlling soil salinization in the region.Field trial results showed that soil EC dropped by 5% and 33% after three consecutive crops in two years of CCC and PCP rotations,respectively.PCP rotation more effectively alleviated secondary soil salinization in PGVF than CCC rotation.SO42？ ion accumulation was different in the two rotation systems,which dropped in PCP and rose in CCC.It was concluded that suitable rotation system should be adopted based on the main ions of secondary salinized soils and plant selectivity of ion uptake.

关 键 词：轮作 次生盐渍化 设施土壤 盐分离子 土壤电导率 

分 类 号：S156.4[农业科学—土壤学]