林隙光照对广州市风景林林下植物分布的影响

Effect of Gap Light Factors on Understory Plant Species Distribution in Urban Scenic Forests of Guangzhou

以广州市3个地点合计3 hm2的风景林样地调查数据为基础,对林隙光照与林下植物分布的关系进行了研究.多响应置换过程(MRPP)分析揭示了林下植物与林冠开度、林下直射光、林下散射光和林下总光照4种林隙光照都密切相关(P<0.01).指示种分析(ISA)表明了林冠开度的指示种为15种,林下总光照的指示种为9种,林下直射光和林下散射光的指示种各5种.通过典范对应分析(CCA)也进一步说明了林冠开度、林下总光照、林下直射光和林下散射光均对林下植物分布有重要的影响.研究结果对今后研究林隙光照与林下植被分布有重要的理论意义.

The relationships between gap light factors and understory plant species were investigated based on field survey data collected from three sample plots in urban scenic forests of Guangzhou, with a total area of 3 hm2. Multi-response permutation procedures （MRPP） revealed that understory plant species were significantly influenced （ P 〈 0. 01 ） by four gap light factors, i. e. , canopy openness, understory direct radiation, understory diffuse radiation and understory total radiation. Indicator species analysis （ISA） detected 15 species for canopy openness, 9 species for understory total radiation, and 5 species for understory direct radiation and understory diffuse radiation, respectively. Canonical correspondence analysis （CCA） also showed that canopy openness, understory direct radiation, understory diffuse radiation, as well as understory total radiation, had significant effects on understory plant species. Findings from this study have implications for future research on patterns of understory plant species in response to gap light factors.