Fish aquaculture within retiary boxes (pen culture) is one of the major causes of submerged macrophyte disappearance in shallow freshwater lakes along the middle and lower reaches of the Yangtze River, China. Submerged macrophytes are of vital importance for sustaining proper ecosystem function in lakes. Therefore, the study of the dept distribution of soil seed bank and historical variation of standing vegetation plays an important role in vegetation restoration.
Dr. Xiao Chan at the supervision of Professor Liu Guihua from Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden sampled seed banks at the entire 40-cm sediment profile. The results suggested that the depth distribution of the seed bank was a significant but relatively weak predictor of historical vegetation. Based on the comparison of three categories of pen culture, significantly more total seeds and viable seeds were present in the non-pen-culture area than in the pen-culture area; the soil seed bank can potentially play an important role in vegetative restoration in the abandoned pen-culture area.
This is the first effort that explores how depth distribution of seed banks relates to dynamic variation in historical vegetation. Understanding the response of sediment seed banks to submerged vegetation degradation is of fundamental interest to ecologists and lake managers.
This research was supported by the National Science Foundation of China (30970469). Relevant results were published in Aquatic Botany entitled “The relationship of seed banks to historical dynamics and reestablishment of standing vegetation in an aquaculture lake”.
Vertical distribution of total seed density of submerged macrophytes within10 sediment strata of 0–40 cm from Lake Honghu. (Image by WBG)
Detrended correspondence analysis (DCA) ordination of seed banks in 10 sediment strata and biomass of submerged vegetations of 5 survey years (Image by WBG)
