围垦滩涂湿地旱生耐盐植物的入侵和影响

以上海市崇明东滩1998年围垦湿地为例，基于彩红外航片的景观格局分析以及样地群落调查，分析了湿地人工排水后，旱生耐盐植物在湿地原生芦苇群落中的入侵和影响.结果表明：以碱菀为建群种的旱生耐盐植物群落在围垦湿地区从东北向西南扩散，速度达143 m·a^-1，原生芦苇斑块迅速收缩、破碎，缀块密度指数和形状指数分别增长22.7倍和1.3倍；2006和2007年两个生长季后群落中碱菀生物量高达2783.8 g·m^-2，占群落总生物量的98％，重要值达88%；芦苇生物量和重要值则分别下降98％和83%.表明侵入过程与地下0～20 cm土壤水分和土壤盐度密切相关.应深入研究旱生耐盐植物的侵入机制，探讨合理、动态的湿地排水管理策略，以便控制旱生耐盐植物群落的迅速入侵.

Invasion and its effects of xerarch halophytes in reclaimed tidal wetlands.

With the reclaimed tidal wetland of Chongming Dongtan in Shanghai as a case, and based on the landscape pattern analysis of colored infrared aerial ph otographs and field survey, this paper studied the invasion of xerarch halophyte s and its effects on the original reed community in the wetland after artificial drainage. The results showed that in the test reclaimed tidal wetland area, the xerarch halophyte community with Tripolium vulgare as edificator was spreading from northeast to southwest at a high speed of 143 m per year, with the original reed patch reduced and broken sharply, causing a 227 times increase in patch d ensity index and a 13 times increase in shape index. After the growth seasons in 2006 and 2007, the biomass of T. vulgare in the plant community reached a s high as 27838 g·m-2，occupying 98% of the total, and the importance v alue reached 88%. At the mean time, the biomass and importance value of original reed decreased 98% and 83%, respectively. The invasion process of xerarch haloph ytes was meaningfully correlated with the moisture content and salinity in 0-20 cm soil layer. To effectively control the rapid invasion of xerarch halophytes, the mechanisms of their invasion and the strategies of ra tional and dynamic drainage management should be deeply studied.