武夷山国家公园甜槠林主要树种生态位与种间联结分析

Analysis on niche and interspecific association of main tree species in Castanopsis eyrei forests in Wuyishan National Park

为探明武夷山国家公园甜槠〔Castanopsis eyrei(Champ.ex Benth.)Tutcher〕林主要树种的生态位和种间联结情况,在海拔800、900、1000、1100和1200 m各设置1个样地,并基于样方调查结果,采用Levins指数、Pianka指数(O_(ik))、方差比率、χ^(2)检验、相关性系数和Ochiai指数(OI)对甜槠林主要树种的生态位特征和种间联结进行分析。结果显示:甜槠重要值在5个样地中均排名前3,而其Levins指数在P1、P2、P3、P4、P5样地中的排名分别为3、2、4、2、9。P1和P4样地中O_(ik)值小于0.5的种对数较多,而P2、P3和P5样地中O_(ik)值大于或等于0.5的种对数较多;P1至P4样地中,甜槠与其他树种间的O ik值多大于或等于0.5,而P5样地则相反。P1至P4样地主要树种的总体联结性为显著正联结,P5样地主要树种的总体联结性为不显著正联结。χ^(2)检验结果显示:5个样地主要树种以正联结为主,但联结性多不显著。相关性分析结果也显示各样地主要树种间多呈不显著正联结。5个样地中OI值大于或等于0.5的种对占多数,且甜槠与其他树种的OI值均大于0.5。综合分析认为,武夷山国家公园甜槠林生态系统稳定,整体朝顶极群落方向演替;甜槠作为地带性植被具有重要的生态指示作用。

In order to clarify the niches and interspecific associations of main tree species in Castanopsis eyrei(Champ.ex Benth.)Tutcher forests in Wuyishan National Park,one sample plot was designed at the altitudes of 800,900,1000,1100,and 1200 m,respectively,and based on the results of quadrat survey,the niche characteristics and interspecific associations of main tree species in C.eyrei forests were analyzed by Levins index,Pianka index(O_(ik)),variance ratio,χ^(2) test,correlation coefficients,and Ochiai index(OI).The results indicate that the importance values of C.eyrei rank among the top three in all five sample plots,while the Levins indexes rank as 3,2,4,2,and 9 in sample plots P1,P2,P3,P4,and P5,respectively.There are more species pairs with O_(ik) value smaller than 0.5 in sample plots P1 and P4,while sample plots P2,P3,and P5 contain more species pairs with O_(ik) value greater than or equal to 0.5.The O_(ik) values between C.eyrei and other tree species are predominantly greater than or equal to 0.5 in sample plots P1 to P4,whereas sample plot P5 presents the opposite trend.The overall association among the main tree species in sample plots P1 to P4 is characterized by a significant positive association,while that in sample plot P5 is characterized by a non-significant positive association.The result of χ^(2) test indicates that the main tree species in the five sample plots primarily exhibit positive associations,while most of these associations are not significant.The correlation analysis result reveals that the relationships among the main tree species in the sample plots predominantly display non-significant positive associations.In the five sample plots,most of the species pairs have an OI value greater than or equal to 0.5,and the OI values between C.eyrei and other tree species are all greater than 0.5.The comprehensive analysis indicates that the C.eyrei forest ecosystem in Wuyishan National Park is stable,it is toward succession of a climax community in general.As a zonal vegetation,C.eyrei plays an important ecological indication function.