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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Mg2++K+的比例和10~50 cm土层CO32-+HCO3-的比例,显著降低了0~30 cm土层Cl-和10~100 cm土层SO42-的比例。垦殖和退化削弱了土壤阴、阳离子间的相关性,其中Mg2+、Ca2+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。
Taking the typical salinized wetland in Tianjin Binhai - Qilihai wetland as the study area, the soil samples were collected from soil samples of 0-5 cm, 5-10 cm, 10-20 cm, 20-30 cm, A total of 63 soil samples were collected from 50 cm, 50 cm, 70 cm and 70 ~ 100 cm soil layers. The effects of long-term reclamation (about 60 years) and wetland degradation (about 50 years) on the growth of Phragmites australis swamp soil Effect of salt. The results showed that the reclamation and degradation significantly reduced the degree of salinization of swamp soil. The soil salt content of farmland was the smallest, followed by degraded marsh and natural swamp. Marsh cultivation and degradation affect the soil in varying degrees, the composition of the cation. Cultivation mainly affected the composition of cations in 0 ~ 20 cm soil layer and significantly changed the composition of anions in 10 ~ 100 cm soil layer. Swamp degradation significantly increased the proportion of Mg2 + + K + in 5 ~ 10 cm soil layer and 10 ~ 50 cm soil Layer CO32- + HCO3- ratio, significantly reduced the proportion of Cl- in 0-30 cm layer and SO42- in 10-100 cm layer. Reclamation and degradation weaken the correlation between soil anions and cations. Among them, Mg2 +, Ca2 + and K + have similar or similar migration characteristics during cultivation and degeneration. The swamp reclamation significantly reduced soil sodium adsorption ratio and alkalization degree at depths of 0-20 cm. Marsh degradation significantly reduced the soil sodium adsorption ratio and alkalization degree at depths of 0-10 cm, indicating that marsh farming and degradation all reduced the soil sodium hazard , However, the two have little effect on the residual sodium carbonate.