持续淹水治理互花米草技术对盐沼土壤的影响

Effect of durative waterlogging for control of Spartina alterniflora on saltmarsh soils

为了研究持续淹水治理互花米草技术对盐沼土壤理化特性的影响,应用化学分析测定方法跟踪监测了崇明东滩治理互花米草示范样地内水淹控制样区的土壤有机质、pH值、氯离子、重碳酸根、钙离子、镁离子和硫酸根离子含量随持续淹水时间的变化.结果表明,随淹水时间的延长,盐沼土壤有机质含量降低,而盐沼土壤pH值、氯离子、重碳酸根、钙离子、镁离子和硫酸根离子含量升高.除了氯离子和重碳酸根外,其他指标在0～15cm和15～30cm土壤层间的含量略有差异,但变化趋势相同.长期淹水造成的厌氧环境对盐沼土壤产生了一定的负面影响,而且持续淹水时间越长,对盐沼土壤产生的负面影响也越大.因此,应用持续淹水技术治理互花米草时,应尽可能减少持续淹水时间,以便在迅速、有效控制互花米草后为受损湿地的修复提供条件.

To study the effects of continuous waterlogging on salt marsh soils,the changes in organic matter contents,chloride ion,bicarbonate ion,calcium ion,magnesium ion,sulfate ion and pH value of the saltmarsh soils at a demonstration site in the Chongming Dongtan Nature Reserve was investigated.In this study,the results showed that continuous waterlogging could reduce the content of organic matter in the saltmarsh soils,while increasing the pH,the content of chloride ion,bicarbonate ion,calcium ion,magnesium ion and sulfate ion of the saltmarsh soils. All the chemical parameters except chloride and bicarbonate ion,showed little difference between the 0~15 cm and 15~30 cm soil layers and showed the same trends over time. Continuous waterlogging would have some negative effects on saltmarsh soils due to the anaerobic conditions,and these impacts were enhanced with increasing duration of waterlogging. Therefore,to apply the technique of continuous waterlogging for controlling Spartina alterniflora,it is necessary to determine the duration of waterlogging that can facilitate the restoration of damaged wetlands after effectively controlling Spartina alterniflora.