Objective To investigate the multi-function of Pinus tabulaeformis plantation in Qingyang, Gansu Province, establish an evaluation system, and provide a scientific basis for the forest management in Qingyang area.
Method We surveyed 63 sample plots of P. tabulaeformis plantations from seven counties of Qingyang, and used analytic hierarchy process(AHP) to establish the multi-function evaluation index system. Eleven indexes were chosen from four functions including water conservation, carbon fixation and oxygen release, biodiversity conservation and excellent provenance preservation. The weights of different indexes were determined using the surveyed data and expert scoring. The total scores for multi-functions of different sample plots were calculated. Using normal equidistant partition, evaluation indexes of plantations of different counties were divided into five categories.
Result For the P. tabulaeformis plantation in Qingyang, the water conservation function had the highest effect, followed by the biodiversity protection function. The functions of carbon fixation and oxygen release and excellent provenance preservation had relatively low effect. The proportions of sample plots that had high effect, moderate high effect, medium effect, moderate low effect and low effect for their multi-functions were 12.7%, 25.4%, 31.75%, 25.4% and 4.76% respectively. The performance was the best in Zhengning County and the worst in Zhenyuan County. The overall effect of multi-function of P. tabulaeformis plantation in Qianyang was ordinary.
Conclusion AHP can be used to effectively evaluate forest multi-function. We should take management measures to improve the multi-function of Qingyang forests.