杉木-厚朴混交林林下物种多样性研究

Study on Understory Biodiversity in Mixed Plantation of Cunninghamia lanceolata and Magnolia officinalis

以福建建瓯顺阳溪东村15年生杉木-厚朴人工混交林及杉木纯林为研究对象,对林下植被的物种组成及多样性变化的差异进行比较,结果表明:杉木-厚朴混交林有林下植被35种,杉木纯林仅21种;混交林分中出现喜光物种,且优势地位明显上升,杉木纯林的优势种以阴生物种为主。混交林中灌木、草本和层间植物物种的Simpson多样性指数(D)和Shannon-Wiener多样性指数(H)均高于杉木纯林,在各林层中从大到小依次表现为灌木、草本、层间植物。杉木-厚朴混交林可明显改善林分空间结构,显著提高林下植物的丰度和多样性,有利于林内生物多样性和生态功能的恢复。

The Cunninghamia latweolata and Magnolia officinalis mixed forest and Chinese fir monoculture plantations were used to compare the species composition and diversity of understory. The results showed that there were 35 species in mixed forest and 21 species in Chinese fir monoculture forest in 1 200 m2 in each forest. The sun-tolerant species appeared and dominated the understory vegetations in mixed forest, but the dominant species in monoculture plantation were shadow-tolerant. The Simpson and Shannon-Wiener biodiversity index of understory was significant higher in mixed forest than in monoeulture plantation with the order of shrub 〉 herb 〉 interlayer species. As a result, the mixed forest significantly improved spatial structure and increased species abundance and diversity, which was beneficial to the forest biodiversity and ecosystem function in Chinese fir degraded forest.