摘要
在上海九段沙湿地国家级自然保护区的上沙和下沙,根据沙体形成时间,选择发育完善的潮沟沟系,在1～4级潮沟附近,设立了17条长度从54～306m不等的样线,并在每条样线上设立面积为150cm×150cm的连续样方,从光滩开始沿垂直于潮沟方向的样线记录样方内植物的盖度;应用双项轨迹方差法对代表性植物进行格局规模分析,直观反映了在不同等级潮沟格局下九段沙主要植物种群分布特点。研究结果表明,在九段沙有草本沼泽和盐生草甸两种植被亚型,其中草本沼泽又有海三棱藨草(Scirpus mariqueter)沼泽和芦苇(Phragmites australis)沼泽两个群系,盐生草甸有耐盐性的芦苇草甸,互花米草(Spartina alterniflora)群落属于人工栽培后逸生的植被;总体而言,随着沙体的形成,首先出现海三棱藨草和藨草(Scirpus triqueter)种群,再次是互花米草,在水动力和植被作用下,潮沟发育不断完善,沼泽植被逐渐演替为以芦苇为主,包含有碱蓬(Suaeda glauca)、碱菀(Tripolium vulgare)等耐盐性的盐生草甸;在局部地段,由于人为干扰的原因,出现加拿大一枝黄花(Solidago canadensis)、钻形紫菀(Aster subulatus)和小飞蓬(Conyza canadensis)等外来入侵性植物;互花米草在调查区域已有广泛分布,横跨草本沼泽和盐生草甸两个植被亚型,表现出其对盐分和通气两个因素有很宽的生态适应能力。
In Upper shoal, Lower shoal of Shanghai Jiuduansha National Nature Reserve, according to sediment formation time and different grades of tidal creek, 17 line transects with length from 54 m to 306 m were located in the maturity tidal creeks. On each line transect, successive plots of each with an area of 150 cm× 150 cm were sampled to record the coverage of each plant species starting from the low tidal beach at the direction perpendicular to the tidal creek, based on the obtained data, the trends of plant coverage was analyzed, the distribution pattern of the main plants was also studied applying the method of the two-term local variance analysis, thus the plant distribution pattern under tidal creeks fine features was intuitively showed. The results showed that ①there were 2 vegetation subtypes, herbal marsh and salt meadow vegetation, of which herbal marshes had Scirpus mariqueter and Phragmites australis, 2 formations, and salt meadow had Phragmites australis and salt-tolerant species including Suaeda glauca and Tripolium vulgare, the invasion of Spartina alterniflora formed artificial vegetations; ②with the formation of sediments, Scirpus mariqueter and Scirpus triqueter appeared first, then Phragmites australis and other marsh plants, as hydraulic and vegetation interactive, tidal creeks are getting maturity, marsh vegetation gradually successes to salt meadow with the dominant species Phragmites australis, together with other salt-tolerant species such as Suaeda glauca, and Tripolium vulgare; ③ some local sites invaded by Solidago canadensis, Conyza canadensia, Aster subulatus and other alien plants; ④ Spartina alterniflora has been widely distributed in the survey area, across 2 vegetation subyptes （ from marsh to salt meadow vegetation）, showing its broad ecological adaptability to salt and ventilation.
出处
《湿地科学》
CSCD
2011年第1期52-60,共9页
Wetland Science
基金
上海市教育委员会重点学科建设项目(J50401)资助
关键词
九段沙
潮沟
等级
盖度
分布格局
Jiuduansha shoal
tidal creek
grade
coverage
distribution pattern
