Evaluation on threatened situation and protection classes of the plants in Makehe Forest Region of Sanjiangyuan Nature Reserve,China

According to the study and investigation of plant resources in Makehe Forest Region of Sanjiangyuan Nature Reserve,Qinghai Province,we found that the plants here existed in 55 families,173 genera and summing up 364 species.The paper put forward five quantified indices for evaluating the threatened situations of these plants,i.e. distribution frequency of line transect as well as sample plot,distribution density inside sample plot,existent abundance in forest region and plants fidelity.The results showed that there are two endangered species,six vulnerable species,12 near threatened species and 344 safety species.The paper analyzed the urgent conservation value of plants according to endangered coefficient,genetic loss coefficient and useful value coefficient,and results also showed that the number of species of the first concern is two, the second nine,the third 23 and of the least concern 330.