喀斯特峰丛洼地西番莲逸生生境和生态位特征

Characteristics of wild habitat and ecological niche of Passiflora edulis in karst peak cluster depression

调查了贵州喀斯特峰丛洼地西番莲(Passiflora edulis)逸生生境特征和样地内的伴生物种,并分析了其生态位特征。结果表明:喀斯特峰丛洼地西番莲逸生生境地形较复杂多样,土壤多为半连续、零星土,少有石漠;石漠化严重地块坡度较陡,土层薄,雨水冲刷导致有机质严重流失,侵蚀严重,土壤容重较大,土壤结构差。西番莲萌生主枝多分布于石块间空隙,其伴生优势物种有忍冬(Lonicera japonica)、构树(Broussonetia papyrifera)、粉枝莓(Rubus biflorus)、香椿(Toona sinensis)、八角枫(Alangium chinense)等20种。其中,粉枝莓和构树的重要值分别为60.54%、51.64%;生态位宽度排在前7位的分别是西番莲、粉枝莓、构树、八角枫、香椿、忍冬、菝葜(Smilax china Linn);西番莲与伴生物种的生态位重叠值大多为0.023~0.088(L ih),反向为0.014~0.075(L hi)。调查区域内藤本植物分布也较丰富,主要以灌丛+藤本为主。20个优势种间并未出现明显的生态位完全重叠,各种群间对资源的利用差异显著,种群对资源的共享趋势并不突出,表明西番莲群落不稳定。西番莲与构树、粉枝莓、八角枫、香椿有着显著的双向生态位重叠值。西番莲与逸生生境伴生物种能互利共生,适应环境,而且生长迅速、生物产量高,今后可以合理开发利用西番莲资源促进地方产业发展。

This paper studied wild habitat characteristics and ecological characteristics of associated species of Passiflora edulis in karst peaks and valleys in Guizhou.The results showed that the habitat of Passiflora edulis in karst peak-cluster depression was complex and varied,semi-continuous soil and sporadic,rocky desert.The slope of rocky desertification was steep and the soil layer was thin,the erosion of soil by rain leaded to serious loss of organic matter,serious erosion,high bulk density of soil and poor soil structure.The branches of Passiflora edulis sprout among rocks mostly.In that area,the other dominant species included Lonicera japonica,Broussonetia papyrifera,Rubus biflorus,Toona sinensis and Alangium chinense.The important values of Broussonetia papyrifera and Rubus biflorus were 60.54%and 51.64%.The top seven niche widths were Passiflora edulis,Rubus biflorus,Broussonetia papyrifera,Alangium chinense,Toona sinensis,Lonicera japonica and Smilax china Linn.The niche overlap values of Passiflora edulis and companion species were 0.023-0.088(L ih)and the reverse were 0.014-0.075(L hi).Vines were abundant in the survey area,mainly shrub and vine.There was no obvious niche overlap among 20 dominant species,and there were significant differences in resource utilization among different populations,and the trend of resource sharing among populations was not prominent.The results showed that Passiflora edulis community was unstable.Passiflora edulis had significant bidirectional niche overlap with Broussonetia papyrifera,Rubus biflorus,Toona sinensis and Alangium chinense.Passiflora edulis and its associated species could coexist mutually,adapt to the environment,grow rapidly,and produce high biomass.In the future,Passiflora edulis resources could be reasonably exploited and utilized to promote the development of local industries.