兴安落叶松林缘天然更新与立地环境因子的相关分析

Forest edge renewal of Larix gmelinii and its response to the environment

【目的】揭示兴安落叶松林缘更新与土壤特性及小气候因子的深层次关系。【方法】在测定兴安落叶松林缘天然更新状况、小气候因子及土壤理化性质的基础上,用单因素方差分析与相关性分析法研究了兴安落叶松林缘天然更新指数与土壤理化性质及小气候因子的相关性。【结果】①距离林缘0 m处的样带更新指数最大,距离林缘20、40、60 m的3条样带更新指数变化不大且趋于平稳。②兴安落叶松林缘的光合有效辐射和空气温度显著大于林内。③林缘的土壤养分高于林内,林缘土壤pH小于林内。④通过主成分分析法得到影响兴安落叶松林缘更新的主要因子为土壤含水率、土壤有机质和光合有效辐射,通过多元线性回归分析法得到影响兴安落叶松林缘更新的主要因子为土壤含水率和土壤有效磷。【结论】兴安落叶松林缘的更新效果比林内好,林缘效应对兴安落叶松林更新的影响大致在距离林缘20 m范围以内;光合有效辐射、空气温度和土壤理化性质能有效影响兴安落叶松林缘的更新,其中土壤含水率是影响兴安落叶松林缘更新的最主要因素。因此可以通过改善林缘的环境促进兴安落叶松林缘区域的更新。

【Objective】This study was conducted to reveal the relationship between the edge regeneration of Larix gmelinii forests and the soil characteristics and environmental factors.【Method】Based on the determination of environmental factors and the soil physical and chemical properties,One-way ANOVA and correlation analysis were used to analyze the regenerative growth of L.gmelinii.The correlation among the natural regeneration index of the larch forest edge and the soil physical and chemical properties and environmental factors were calculated.【Result】The regeneration index in the three plots at 0 m from the edge of the forest was the highest,whereas the regeneration index in the three plots at 20,40 and 60 m from the edge of the forest showed light change and tended to be stable.The photosynthetic effective radiation and air temperature at the edge of L.gmelinii forest were significantly higher than those in the forest.Soil nutrients at the forest margin were higher than those in the forest,and soil pH in the forest margin was lower than that in the forest.The main factors affecting the regeneration of L.gmelinii at the forest margin were soil moisture content,soil organic matter and photosynthetic active radiation.The main factors affecting the regeneration of L.gmelinii at the forest margin were soil moisture content and the available soil phosphorus by multiple linear regression analysis.【Conclusion】The regeneration effect of L.gmelinii at the forest margin was better than that in the forest.The influence of the forest margin effect on the regeneration of L.gmelinii forests was within 20 m of the forest margin.The photosynthetic effective radiation,air temperature,and the soil physical and chemical properties could effectively influence the renewal of the L.gmelinii forest,and the water content of the soil was the most important factor affecting the renewal of L.gmelinii.The regeneration of the forest edge of L.gmelinii can be promoted by improving the forest environment.