不同淋洗剂对滩涂围垦区土壤盐分的洗脱效果
Effects of Different Washing Reagents on Removal of Soil Salt Salinity for Coastal Reclamation Zones
张长波 1梁晶 2廖志强 3马晓宇 3杨桂兰3
作者信息
- 1. 上海化工院环境工程有限公司,上海 200062;上海化工研究院有限公司,上海 200062
- 2. 上海市园林科学规划研究院,上海 200232
- 3. 上海化工院环境工程有限公司,上海 200062
- 折叠
摘要
[目的]评价淋洗剂对盐渍土盐分洗脱影响,为滩涂围垦区土壤改良提供理论指导.[方法]以采自上海市崇明滩涂围垦区水稻田的轻度盐渍土和重度盐渍土为研究对象,比较分析了硝酸钾、硝酸铁、硝酸钙、硝酸镁和碳酸氢铵5种淋洗剂浓度和淋洗次数对土壤盐分Na+,K+,Ca2+,Mg2+,CO32-,HCO3-,Cl和SO42-这8种离子的洗脱效果.[结果]5种淋洗剂对轻度盐渍土 Na+,C1的洗脱均有促进作用,其中以硝酸钾对Na+的洗脱作用最为明显,土壤浸出液中Na+的浓度较对照提升了 9.9％～25.9％;碳酸氢铵更易促进土壤Cl-的洗脱,较对照提升了 9.6％～21.2％.综合考虑淋洗剂对K+,Ca2+,Mg2+等土壤养分的淋出影响,以3.0 mmol/L硝酸钾的处理效果更佳;硝酸钾进行第二次淋洗时的Na+,Cl-,SO42-,Ca2+的浸出浓度较低,而HCO3-和Mg2+则相反.因淋洗剂浓度较重度盐渍土盐分离子含量低,导致5种淋洗剂对重度盐渍土 Na+和Cl-的洗脱效果不佳,与对照相比,分别提升了 0.1％～1.0％,0.01％～4.4％.[结论]滩涂围垦土壤改良时应根据土壤盐分离子种类与含量确定淋洗剂类型、浓度及淋洗次数;淋洗剂的施用可与灌溉措施相结合.
Abstract
[Objective]The effectiveness of washing reagents in removing soil salinity was evaluated to provide theoretical guidance for soil amendments in coastal reclamation zones.[Methods]Slightly and heavily saline soils of paddy fields from the Chongming coastal reclamation zones in Shanghai City were selected as the research objects,and the effects of five types of washing reagent(potassium nitrate,iron nitrate,calcium nitrate,magnesium nitrate,and ammonium bicarbonate)concentrations and extraction times on soil salinity(Na+,K+,Ca2+,Mg2+,CO32-,HCO3-,Cl,and SO2)removal efficiency were compared and analyzed.[Results]The five washing reagents promoted the removal of Na+and Cl-in the slightly saline soils,and the effect of potassium nitrate on Na+removal efficiency was the most obvious,because the Na+concentration in the eluate was increased by 9.9％-25.9％compared with that in the control.However,Cl-was more easily removed by ammonium bicarbonate,and the increase ratio was approximately 9.6％-21.2％compared with the control.Potassium nitrate(3.0 mmol/L)showed the best results,considering the removal of soil salt ions and the loss of soil nutrients(K+,Ca2+,and Mg2+).The Na+,Cl,SO42-,and Ca2+concentrations in the eluate of the second washing by potassium nitrate were markedly lower than those after the first time,whereas it was not the case for HCO3-and Mg2+.In this experiment,the five washing reagents showed negligible effects on the removal efficiency of Na+and Cl-in the heavily saline soils because the applied concentration was much lower than the salt ion content in the soils,and the increase rates of the two ions were 0.10％-1.0％and 0.01％--4.40％,respectively,compared with the control.[Conclusion]The types,concentrations and times of washing reagents should be determined according to the types and contents of soil salt ions when improves soil in coastal reclamation zones.The application of washing reagents could be combined with irrigation measures.
关键词
盐渍土/淋洗剂/盐分离子/洗脱/滩涂围垦区Key words
saline soils/washing reagents/salt ions/remove/coastal reclamation zones引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据