3种改造人工林的林下植物多样性和土壤物理性质

摘要

[目的]对广东省佛山市云勇林场3种人工林的林下植物多样性和土壤物理性质进行研究,以期为生态公益林的培育及养护管理提供理论依据.[方法]在石笔木 Tutcheria championii 纯林(简称 P1 样地),杉木Cunninghamia lanceolata、米老排Mytilaria laosensi、尖叶杜英Elaeocarpus apiculatus、火力楠Michelia macclurel、枫香Liquidambar formosana、盆架子Alstonia scholarisv等为主的针阔混交林(简称P2样地),以及米老排、红锥Castanopsis hystrix 、格木Erythrophleum fordii等为主的阔叶混交林(简称P3样地)调查并记录各林分样地内灌木和草本的种类、盖度、株数及平均高度,运用多样性及均匀度等指标分析不同林分类型的林下植物的物种多样性.在各个样地分别用100 cm3环刀采集0～20 cm土层的土样,测定土壤含水量、土壤容重等物理性质.[结果]各林分灌木层的Shannon-Wiener指数和Simpson指数的平均值小于草本层,但是灌木层的均匀度指数的平均值大于草本层;各样地草本层生长状况优于灌木层;P1样地的灌木及草本植物种类、数量均多于P2、P3样地;3种林分中,P1样地的土壤容重最大,P2样地的土壤容重最小;土壤总孔隙度、自然含水量、毛管持水量、毛管孔隙度、非毛管孔隙度、通气孔隙度指标均表现为P2样地>P3样地>P1样地.[结论]混交林的群落结构较纯林合理且对土壤质量的改良效果更好.%[Objective]To investigate the undergrowth diversity and soil physical properties in three plantations at Yunyong forest farm in Foshan,Guangdong Province and provide a theoretical basis for ecological forest cultivation and management.[Method]Tutcheria championii was planted in a pure broad-leaved plantation(P1 plot); Cunninghamia lanceolata,Mytilaria laosensis,Elaeocarpus apiculatus,Michelia macclurei,Liquidambar formosana and Alstonia scholarisv were planted in a mixed conifer-broad leaf plantation(P2 plot); M.laosensis,Castanopsis hystri and Erythrophleum fordii were planted in a mixed broad-leaved plantation(P3 plot).Species diversity,coverage,number of total plants and average height of shrub-herb layer under canopy of above plots were investigated.Diversity and evenness indexes were used to study undergrowth species diversity of these plantations.The 100 cm3cutting ring was used to collect soil samples from the 0-20 cm soil layer at three plots,respectively,and soil physical properties such as water content and bulk density were determined.[Result]The mean values of Shannon-Wiener diversity index and Simpson diversity index of shrub species were lower than herb species while the mean values of evenness indexes of shrub species were larger than herb species in the three plots.The growth status of herb species were superior to shrub species in the three plots.The species number and quantity of the undergrowth of P1 plot were more than those of P2 and P3 plots.The soil bulk density of P1 plot was the highest among the three plots while that of P2 plot was the lowest.The values of total soil porosity,natural moisture content,capillary moisture capacity,capillary porosity,non-capillary porosity and aeration porosity of the three plots were all in the order of P2 plot >P3 plot > P1 plot.[Conclusion]The community structure and soil quality of mixed plantations are better than those of pure plantation.