Study On The Reservation Of The Larus Relictus Habitation In Erdos Plateau Saline Wetland

The Erdos Plateau Saline Wetland lies between the MaoWusu desert and KuBuqi desert. It is a typical plateau hungriness wetland ecosystem. The hungriness saline-lake group is made up of about 100 lakes, like Tao-A Haizi, Hongjian-Nur, and Aobai-Nur. It is an important international wetland reserved for Larus Relictus and them habitation. Almost 60% Larus Relictus in the world breed in the Erdos Plateau Saline Wetland. They are on the top layer of the food net in the wetland. If we protect the Larus Relictus, we must protect their breed habitation entironment. So we must study on the water quality, food source, biology diversity, ecological water requirement and the entironmental effect factors.We study on key ecological issues in the reservation of the Larus Relictus habitation in Erdos plateau saline wetland supported by the Erdos Larus Relictus national natural reserve administration bureau from 2005. The National Natural Science Foundation of China supports us to finish the item later.After 4 years investigation, the basic conclusions were followed:1. The Tao-A Haizi Lake belongs to chloride lakes. The biology quantity is reduced with the salinity rise.The Hongjian-Nur Lake belongs to soda lakes. The salinity, alkalinity and pH is high in the carbonate soda lake. The calcium ion is little for forming calcium carbonate. The M/D quotiety is high. All the conditions restrict the biology naturalization. The biology community is poor.2. The lake minimum ecological water requirement is a new field of ecology and hydrology. The study is in primary stage in theory and in practice. We researched on the calculation methods of the lowest ecological water level on ecology, hydrology, and hydr-ecology three piont of view. Seven kinds of lake lowest ecological water levrl calculation methods are proposed. The first one is lake shape analytical method. The second one is the lowest space demand method. The third one is water and salt balance method. The fourth one is water quantity balance method. The fifth and the sixth one is eco-hydrology method. The seventh one is lake function method. After calculation, the Tao-A Haizi Lake's lowest ecological water level is 1360.1 m. The lake minimum ecological water requirement is 1.9×106 m3. Study on the calculation methods of the lake lowest ecological water level is significant in solving the ecological degeneration of lake in hungriness wetland ecosystem.3. The dominant species of phytoplankton is saline species Dunaliella and Spiulina and freshwater species which can bear high salinity. The dominant species of zooplankton is saline species Brachionus plicatilis and M. mongolica.The Zoobenthos dominant species is Chironomidae and Ischnura grub.They are the dominant species in saline wetland. The kinds of them are few. The density and biomass of dominant species is large. Their distribution determines the total species distribution. Shannon-Weaver index (H′) and Margalef index (d) decreases with the salinity rising. Pielou index rise with the salinity rising.4. The Larus Relictus breeding nest increases year after year in Hongjian-Nur. Their distribution is determined by the condition of Zoobenthos distribution.5. The relation between the hydrophily biology community and the ecological factors:Calcium ion is key ecological influential factor. The hydrophily biology community distribution is determined by calcium ion. In some range of salinity and alkalinity, Ca2+/Mg2+, M/D, rigidity is the mostly ecological influential factors.