黄河三角洲重度退化滨海湿地盐地碱蓬的生态修复效果

The ecological effects of Suaeda salsa on repairing heavily degraded coastal saline-alkaline wetlands in the Yellow River Delta

采用翻地、施肥和芦苇碎屑培肥等土壤改良方法,利用盐地碱蓬在黄河三角洲重度退化区进行生态修复实验研究。结果表明:重度退化湿地土壤改良后,盐地碱蓬能够成功生长,3种改良方法均可有效的降低重度退化盐碱地的土壤含盐量,改良后的土壤Na离子含量均显著低于对照组,土壤脲酶和磷酸酶活性与对照相比有了显著的提高,表明改良后土壤肥力得到了改善。3种改良方法比较,培肥处理组土壤Na离子含量显著低于其他两种方法;盐地碱蓬生物量达到最高值,说明增加有机物的培肥方法可有效的改良重度退化盐碱湿地土壤,达到较为理想的生态修复预期效果。

The Yellow River Delta is one of the most active regions of land-ocean interaction among the large river deltas in the world.However,the wetlands in Yellow River Delta have been suffering from soil salinity and increasing degradation,because of the coastal erosion and drying up of the Yellow River.Therefore,it′s essential to develop efficient eco-remediation methods on heavily degraded coastal saline-alkaline wetlands to protect wetlands resources.To study the ecological effects of Suaeda salsa on repairing heavily degraded coastal saline-alkaline wetlands,ploughing（PG）,fertilization（FG） and reed debris（RD） were used for soil eco-remediation.The saline-alkaline soil eco-remediation effects were investigated by periodic measurements of such variables as soil salt content,Na＋,soil urease,phosphatase,soil nutrient components and biomass,density and yield of Suaeda salsa plant.The dynamic changes of different index and the differences of three eco-remediation methods were discussed.The results showed that the Suaeda salsa plant could grow well after the soil eco-remediation on heavily degraded coastal saline-alkaline wetlands.All three eco-remediation methods could decrease the soil salt content efficiently.The Na＋ content in the eco-remediated soil was significantly lower than in control soil.Among three methods,the Na＋ content in RD was significantly lower than in other two groups.The activity of soil urease and phosphatase in eco-remediation groups were higher than control,which indicated that the soil fertility was significantly improved.Compared with three methods,the activity of soil urease and phosphatase in RD was the highest.The contents of total N in PG,FG and RD were increased 30.9%,31.7% and 28.6% respectively,and the content of total organic C,available P and K did not rise significantly.Plant biomass is one of the most important indicator evaluating the plant growth condition.Compared with three methods,the density of Suaeda salsa plant was FG PG RD,and the biomass of Suaeda salsa plant was PG FG RD.The results together indicated that organic matter adding is an effective way for soil eco-remediation in heavily degraded coastal saline-alkaline wetlands.