三江平原典型沼泽湿地螺类组成生态指示

螺类作为湿地的重要生物类群,对环境变化响应敏感,这使得螺类成为潜在的环境指示物种。为了研究中国东北沼泽湿地不同类型湿地螺类群落结构的差异以及螺类作为不同类型湿地指示物种的可能,在2014年9月和2015年5月对小叶章沼泽化草甸湿地、臌囊苔草湿地、毛苔草湿地、漂筏苔草湿地共17个采样点进行螺类样品采集。共采集到了螺类8科13属17种4452个。研究表明,螺类以扁卷螺科Planorbidae、椎实螺科Lymnaeidae、膀胱螺科Physidae为主;4种不同类型湿地螺的种类组成不同,这些螺类的种类组成与不同类型湿地的水深、植物类型组成等湿地特征是相对应。螺类的生物多样性指数(ShannonWiener指数和Marglef指数)在不同类型湿地之间也存在一定差异,筛选了指示螺类6种,无褶螺是小叶章沼泽化草甸的指示物种,小土蜗、半球多脉扁螺和虹蛹螺是臌囊苔草湿地的指示物种,琥珀螺是毛苔草湿地的指示物种,平盘螺是漂筏苔草湿地的指示物种,这表明了螺类是沼泽湿地类型的重要指示生物。也为螺类生物多样性资源的保护、恢复和生态评价提供科学依据和资料积累。

Study on the assemblage and indicative characteristics of aquatic snails in typical marsh wetland on the Sanjiang Plain, China

Snails are ecologically diverse. The pulmonate taxa are air breathers, can tolerate hypoxia, and are often capable of resisting temporary or seasonal drying. The non-pulmonates use gills to breathe, require oxygenated water to survive, and are rarely able to tolerate drying. Snails have a widely diverse taxonomy, ecology, and physiology. Their basal position in food webs and passive dispersal may make snails potential environmental indicators. We studied the differences in the snail assemblages of different types of marsh wetlands in northeastern China, and explored the possibility that snail species could be used as indicator species for different types of marsh wetlands. In September, 2014 and May, 2015, snails were collected from 17 sites spread across Deyeuxia angustifolia wetlands, Carex schmidtii wetlands, Carex lasiocarpa wetlands, and Carex pseudocuraica wetlands. By collecting them in spring and autumn, we avoided the influence of spawning on the numbers of snails, and reduced identification interference caused by larvae. We collected a total of 4452 individuals, which belonged to eight families, 13 genera, and 17 species. The snails were mainly members of the Planorbidae, Lymnaeidae, and Physidae. The results showed that the aquatic snail assemblages were affected by wetland types. The clustering analysis, non-metric multidimensional scale, and an analysis of the similarities between the snail communities divided them into four cores. These were the Deyeuxia angustifolia wetlands, Carex schmidtii wetlands, Carex lasiocarpa wetlands, and Carex pseudocuraica wetlands. Six snails were indicator species for these four types of wetlands, and the characteristics of these snails corresponded to the hydrological and vegetation characteristics of the different wetland types. Aplexa hypnorum was an indicator for Deyeuxia angustifolia wetlands; Galba pervia, Segmentina hemisphaerula, and Pupilla sp. were indicators for Carex schmidtii wetlands; Succinea sp. was an indicator for Carex lasiocarpa wetlands; and Valvata cristata was an indicator for Carex pseudocuraica wetlands. There were also some differences and characteristic variations in the biodiversity indexes of the snail assemblages between different wetland types. The differences in snail assemblages between different wetland types meant that the effects of vegetation should be recognized when studying the invertebrates found in typical marsh wetlands, and those connected with wetland protection and wetland ecosystem restoration. The snails can be used as one group of indicators (Wetland types). This study also provides a scientific basis and data that can be used to rationally develop and sustainably utilize snail resources.