The Effects Of Waterlogging On Ecophysiological Characteristics Of Several Plants Of Three Gorges Reservoir Areas

Woody plants might be subject to waterlogging stress under some situitions in nature. The study on ecophysiological responses and adaptations of plants to waterlogging can not only clarify the underlying mechanism dominating the pattern of trees'distribution in drawdown area of reservoirs and ponds but also provide potential practical methods for ecological management of drawdown area of reservoirs and ponds. That's the reason why it is a hotspot topic in the field of plant ecophysiology.After the Three-Gorges Dam (TGD), the world's largest dam, began storing water, partial lands have been surrounded by water to become islands, which would bring about significant effects on the eco-physiological status of insular dominant species. Before islands were formed, three insular dominant species, which were Quercus glandulifera,Quercus variabilis,Pinus massoniana, were chosen. Water potential and chlorophyll fluorescence were measured in July and September in a growing season. These eco-physiological baseline information were very important for following studies on the fitness of plant species during habitat fragmentation caused by the construction of TGD. Results indicated that Pinus massoniana had higher capacity of drought-adaptability than Quercus glandulifera and Quercus variabilis. Water potential and Fv/Fm were higher in the morning and lower at noon, after a whole night, values recovering to original ones, which indicated that the three dominant plants were growing well on the forming island at present time. However, more consecutive observation during the procedure of forming island should be carried out to clarify the effect of island fragmentation on insular plant's eco-physiological status.Pterocarya stenoptera,Taxodium ascendens and Quercus variabilis (Cork Oak) are very important species in the subtropical riverside and drawdown area of reservoirs and ponds of China. We use the method of ecophysiology to study the responses and adaptation of these three species to simulated waterlogging. The earliest effects of waterlogging were significantly decreased maximum photosynthetic...