玉龙喀什河河漫滩荒漠柽柳林实生苗更新

Seedling recruitment of desert Tamarix ramosissima on floodplain in the Yulong Kashgar River

研究河漫滩柽柳林实生苗天然更新机制,对荒漠河岸柽柳林的恢复和生态系统的稳定和经营措施提供科学依据。对和田地区和田县玉龙喀什河河漫滩的柽柳林采用设置样方的方式,对河漫滩和林下2种生境下的柽柳实生苗数量、高度、冠幅进行调查,同时测定样方内土样水分和总盐。柽柳实生苗更新主要发生于河漫滩洪水漫溢区,在非漫溢区实生苗无法生存;洪水季节河漫滩优良的水分条件,有效地满足了柽柳种子萌发和幼株生长的水分需求并降低了河漫滩的土壤盐分;河漫滩是柽柳种子实生苗更新繁育的场所,洪水漫溢后的河漫滩种子实生苗密度显著大于其他生境下实生苗密度,物种多样性也显著高于其他生境;修建简易拦洪坝是河漫滩柽柳实生苗更新恢复的重要技术手段。洪水是河漫滩柽柳自然萌发以及幼苗更新的重要因素,河漫滩是柽柳实生苗更新的最佳场所。

Study natural recruitment mechanisms of Tamarix ramosissima seedlings on the floodplain is provide a scientific basis for the Tamarix ramosissima restoration on desert riparian ,ecosystem stability and management measures. With setting modal area to Tamarix ramosissima in floodplain of Yulong Kashgar River of Hotan County of Hotan Prefecture, carry out an investigation about Tamarisk seedlings quantity, height, crown on the two kinds of ecological environment that floodplain and understory, Meanwhile, determine the total salt and water of soil samples in modal area. Recruitments of tamarisk seedlings are depends floods overflow, in the non-overflow area it can＇ t survived. During flood season the good water conditions of floodplain effectively meet the water demands of tamarisk seed germination and seedling growth, and reduce the soil salinity of floodplain. Floodplain is the sites of tamarisk seed seedling renewal and breeding. After flood overflowing the floodplain seed seedling density was significantly greater than under other ecological environment seedling density, and the species diversity in this ecological environment was also significantly higher than other ecological environment. Building easy flood detention dam is one of the important technical means in floodplain tamarisk seedling regeneration. Floods are the important ecological factors for the tamarisk germination and seedling natural recruitment, and the floodplain is the best area for Tamarix community regeneration.