Investigation Of Rare And Protected Plants Flooded Baise Water Conservancy Projiect And Ex Situ Conservation Effect Evaluation

Baise water project is located in the Baise City, Guangxi Zhuang Autonomous Region, China, which is one of the important sign of the project of the national implementation of the western development strategy. Baise water project submerged13000hectares of land. The implementation of ex situ conservation has important significance to the protection of rare and endangered plants submerged.Based on the investigation, there are seven species of rare and endangered plant in the submerged area (i.e.,Cycas debaoensis, Cycas siamensis, Cibotium barometz, Burretiodendron esquirolii, Zenia insignis, Toona ciliatan and Amesiodendron tienlinensis). Among of them, Cycas debaoensis and Cycas siamensis belong to a rare and endangered species of first grade protection listed in the Nation Documents. There are1610individuals of rare and endangered plants in the region submerged, the numbers of individual is the highest in both Z. insignis and A. tienlinensis species among the seven species, accounting for38.64%in Z. insignis (612individuals) and41.35%in A. tienlinensis (655individuals) of the total individuals, respectively, and is the lowset in both T. ciliatan and B. esquirolii, accounting for1.74%in T. ciliatan and1.61%in B. esquirolii, respectively. C.barometz, C. debaoensis, C. siamensis is152,99and66individuals, accounting for9.44%,6.12%and4.10%, respectively. The rare and endangered plants distributed mostly in the Boai river and the Gula river, the numbers of species and individual of rare and endangered plants in both rivers accounted for100%and81.24%in total protection species and individuals. The DBH structure of the rare and endangered tree species is mainly A (DBH<7.5cm)+B (7.5cm<DBH<17.5cm) class, the mid-class (17.5cm<DBH<27.5cm) and large-class (27.5cm<DBH<52.5cm) is rare, and the lack of especially large diameter trees (DBH>52.5cm). The303individuals of six kinds of rare and endangered plants in submerged area carried out the ex situ conservation. The total survival rate is71.29%in October in2013. Among of them, C. debaoensis transplanted in50individuals, survival rate was100%;15individuals and93.33%in T. ciliatan;130individuals and85.38%in C. barometz,16individuals and68.75%in B. esquirolii,56individuals and50.91%in A. tienlinensis,36individuals and0.00%in Z. insignis. The results show that C. debaoensis and C.barometz are adapted or constrainedly adapted to habitat of ex situ area with natural regenetation; Vegetatoin growth of A. tienlinensis and B. esquirolii has been good and blossom, but unwith natural regenetation; Vegetatoin growth of T. ciliatan has been good and unblossom; However, Z. insignis can not adapted to habitat of ex situ area and all individuals have been dead for two years. According to standard of minimum viable population, the ex situ conservation of six rare and endangered plants are uneffective because the individuals of ex situ conservation species is too less. Therefore, improving management and as soon as developing their populations is need to the achievement of ex situ conservation.