摘要
柏木低效林是四川盆地丘陵区一种典型的低效林类型。对四川省阆中市哑口乡低效柏木人工林设计了4种间伐强度(对照、21.6%的弱度间伐、49.4%的强度间伐和71.3%的极强度间伐)的低改试验。于5年后对试验地进行了林分生长量调查,并采用Shannon-Wiener多样性指数P、ielou群落均匀度指数和Simpson生态优势度指数对低改后林下植被的多样性进行了对比研究。结果表明:抚育间伐对树高生长无显著影响(P>0.05);不同间伐强度对林分平均胸径生长影响显著(P<0.01),其生长量随着间伐强度的增强而增加,但保留密度2 490和1 560株/hm2的2个处理间的差异不显著(P>0.05);林分低改后,增加了林下植被的Shannon-Wiener多样性指数和Pielou群落均匀度指数,减低了Simpson生态优势度指数。因此,作为水土保持林,可对柏林低效林进行50%的抚育间伐,即保留密度在2 500株/hm2左右。
Cupressus funebris plantation was a typical type of lower-effect forest in the lower hilly region of Sichuan Basin,Sichuan province.Four thinning intensity experiments,including contrast group（A）,21.6% of individuals thinned（B）,49.4% of individuals thinned（C） and 71.3% of individuals thinned（D）,were designed to modulate trees density of Cupressus funebris plantation at the Yakou town,Langzhong county of Sichuan province in 2002.The increments of trees were measured at the experiment site in March of 2006,and the species diversity indexes of under forest vegetation were calculated by Shannon-Wiener diversity index,Pielou evenness index and Simpson ecological dominance in August of 2006.The results showed that different thinning intensity had no obvious effect on tree height（P〉0.05）.However,the different thinning intensity had significant effect on diameter breast height（DBH）（P〈0.01）,and five years periodic change of DBH was increased with the increment of thinning intensity.Furthermore,the increments of DBH of trees between C and D were not significant at the 0.05 level.Shannon-Wiener diversity index and Pielou evenness index of vegetation under forest of C and D experiment site had higher value than that of A and B after five experimental years,but Simpson ecological dominance was reduced.It was necessary for Cupressus funebris plantation with over density of 2 500 trees per hm^2,to be thinned towards cultivation of conservation of water and soil forest,and it was suitable for thinning intensity about 50%,namely,intensity of trees were kept down about 2 500 trees per hm^2.
出处
《安徽农业科学》
CAS
北大核心
2008年第15期6296-6297,6303,共3页
Journal of Anhui Agricultural Sciences
关键词
四川盆地
低效林
抚育采伐
物种多样性
Sichuan Basin
Lower-effect forest
Intermediate cutting
Species diversity
