长期垦殖与退化对七里海芦苇沼泽土壤盐分的影响  

Effects of Long-term Reclamation and Degradation on Soil Salinity of Phragmites australis Marshes in Qilihai Wetlands

作　　者：冯小平[1,2] 王义东[1] 郭长城[1] 王中良[1,2] 

机构地区：[1]天津师范大学,天津市水资源与水环境重点实验室,天津300387 [2]天津师范大学、城市与环境科学学院,天津300387

出　　处：《湿地科学》2014年第3期388-394,共7页Wetland Science

基　　金：教育部新世纪优秀人才支持计划项目(NCET-10-0954);国家科技支撑计划项目课题(2012BAC07B02);天津市高等学校科技发展基金计划项目(20100522);天津师范大学博士基金项目(52XB1010)资助

摘　　要：以天津滨海典型盐渍化湿地——七里海湿地为研究区,采用土钻剖面取样法,采集深度分别为0~5 cm、5~10 cm、10~20 cm、20~30 cm、30~50 cm、50~70 cm和70~100 cm的7层土壤的样品,共采集63个土壤样品,研究长期垦殖（约60 a）和湿地退化（约50 a）对芦苇（Phragmites australis）沼泽土壤盐分的影响。结果表明,垦殖与退化显著降低了沼泽土壤盐渍化程度;农田土壤的含盐量最小,其次为退化沼泽、天然沼泽。沼泽垦殖与退化不同程度影响了土壤阴、阳离子的组成。垦殖主要影响了0~20 cm土层阳离子的组成,显著改变了10~100 cm土层阴离子的组成;沼泽退化显著增加了5~10 cm土层Mg^2＋＋K^＋的比例和10~50 cm土层CO3^2-＋HCO^3-的比例,显著降低了0~30 cm土层Cl^-和10~100 cm土层SO4^2-的比例。垦殖和退化削弱了土壤阴、阳离子间的相关性,其中Mg^2＋、Ca^2＋和K＋在垦殖与退化过程中有着相似或相近的运移特征。沼泽垦殖显著降低了0~20 cm深度土壤钠吸附比和碱化度,沼泽退化显著降低了0~10 cm深度土壤钠吸附比和碱化度,表明沼泽垦殖与退化都降低了土壤钠的危害,然而二者对土壤残余碳酸钠影响较小。The study was conducted on 3 kinds of land types： natural Phragmites australis marshes, farmlands and degenerated Phragmites australis marshes in Qilihai wetlands, Tianjin. The natural marshes were mainly covered by Phragraites australis with a water level of 0-40 cm. The farmlands were cultivated from the reed wetlands for about 60 years. During the first 20 years, paddy was cultivated. Afterwards, the paddy lands converted to dry-lands dominated by corn, cotton, sorghum and wheat etc. in rotation. The Phragmites australis marshes degenerated because hydrological conditions changed adversely for about 50 years. In this study, 63 soil samples from 7 soil layers with depths of 0-5 cm, 5-10 cm, 10-20 cm, 20-30 cm, 30-50 cm, 50-70 cm and 70-100 cm were collected using a soil drill at 3 sites in May 2012. Salinity, pH and electrical conductivities in 7 soil layers were analyzed in laboratory. The results showed that the degree of salinization decreased significantly after reclamation and degradation. The soil salinity and electrical conductivities were the highest in the natural marshes, followed by those in the degenerated marshes and the farmlands. The compositions of the cations in 0-20 cm layer of the soil and anions in 10-100 cm layer of the soil significantly changed after reclamation. The proportion of Na^＋ was significantly reduced in the arable soil layer （0-10 cm）, but the proportion of Ca^2＋ in the 0-10 cm soil layer and the proportion of Mg^2＋＋K^＋ in the 5-20 cm soil layer were significantly increased. The proportion of CI^- and SO4^2- was significantly reduced in the 10-100 cm soil layer, while the proportion ofHCO3^＋ CO3^2- was significantly increased in soil layer of 5-100 cm. In contrast, degradation significantly increased the proportion of Mg^2＋ ＋ K^＋ in the soil layer of 5-100 cm and HCO3- ＋ CO3^2- in the 10-50 cm soil layer. The correlation of major ions decreased after reclamation and degradation. Mg^2＋, Ca^2＋ and K^＋ showed similar transferring characteristics dur

关 键 词：滨海湿地 盐渍化 长期垦殖 退化 土壤盐分 芦苇沼泽 七里海 

分 类 号：S153.6[农业科学—土壤学]