Characteristics of soil and water environments between ligneous plants(Salix) and herbaceous plants(Carex) communities in the Lake Dongting wetlands

Authors Li Youzhi; Li Xiquan; Zhang Canming; Ma Fengfeng; Xu Jialuan

Journal Journal of Lake Sciences , 2015,5:27

Abstract The functions of ligneous and herbaceous plants were different due to their differences in life forms, especially in wetland ecosystems in which plants were inundated by periodic flooding. In this study, two native plants of ligneous(Salix) and herbaceous(Carex) at four areas (Ermenzha, Wumenzha, Ouchihekou and Baishadaqiao) in the Lake Dongting wetlands were selected as the study objects. The physical and chemical characteristics of the soil in dry seasons, and flow velocity and water environments in flood seasons were investigated. In Ermenzha and Baishadaqiao, the compositions of soil particle-size were not significantly different between ligneous and herbaceous plant areas. However, in Wumenzha and Ouchihekou, sediments in ligneous plant area had a lower percentage of silt but a higher percentage of sand in topsoil (0-30 cm) and subsoil (60-90 cm), and a lower percentage of sand but higher clay and silt in medium soil (30-60 cm) compared to sediments from the herbaceous plant areas. For soil chemical characteristics, ligneous plants were benefited to increase soil organic carbon and total nitrogen contents compared with that of herbaceous plants. Total phosphorus and total potassium from the sediments were not different between the two vegetation types. Ligneous plant areas had created lower flow velocity, higher water redox potential and higher dissolved oxygen content compared with herbaceous plant areas. However, there was no difference in water temperature and pH values between the two vegetation type areas. These data indicated that great differences in life forms contributed to different ecological functions between the two vegetation types: higher in ligneous plant areas and lower in herbaceous plant areas.

Species covered 薹草属 Carex