Study On Forest Regeneration Of Larix Gmelinii Based On Forest Edge Effect

As a special regeneration mode and an important component of stand regeneration,the study of regeneration law of forest edge has important ecological significance for clarifying its special regeneration environment and effect.Seven aggregation indices were used to analyze the spatial distribution types and aggregation intensity of the regenerated seedlings and saplings,and the concept of regeneration index was introduced to compare and analyze the regeneration of three different forest margin plots.In order to reveal the deep relationship between forest edge regeneration of Larix gmelinii and soil properties and meteorological factors,the correlation between natural regeneration index of forest edge of Larix gmelinii and soil pHysical and chemical properties and meteorological factors was analyzed by single factor variance analysis and correlation analysis based on the determination of meteorological factors and soil pHysical and chemical properties.The results show that:(1)The regeneration of Larix gmelinii forest margin is better than that of forest margin,and the effect of forest margin effect on regeneration of Larix gmelinii forest is about 20 meters away from the forest margin;the influence of different directions of forest margin on microclimate and plant growth in the vicinity is also different,and the regeneration of forest margin with good illumination conditions and long illumination time is better;the forest and different communities form different forest margin types.The regeneration of forest edge under better conditions such as soil moisture outside forest is better.Margin effect can promote natural regeneration of Larix gmelinii,and different types of margin and direction of margin regeneration have different effects.(2)Available pHotosynthetic radiation and air temperature in forest margin are significantly higher than those in forest margin,and the air humidity in forest margin is less than that in forest margin,and the difference is not significant.Different types of forest margin environment will form different types of forest margin with Larix gmelinii forest margin.The soil moisture content of forest margin formed by Tatou grassland with better external environment is higher than that formed by cutting clearance,while the soil bulk density is lower.That is to say,the soil moisture content is higher and the soil bulk density is lower in the forest edge with better soil moisture environment outside the forest;the soil chemical properties in the forest edge of Larix gmelinii have the same regularity,that is,the soil nutrient content and soil acidity in the forest edge are more significant than that in the forest.The regeneration of Larix gmelinii forest margin is affected by the pHysical and chemical properties of soil and meteorological factors.It can promote the regeneration of Larix gmelinii by improving the forest margin environment.The margin effect of Larix gmelinii was also caused by the differences of meteorological factors,soil pHysical properties and soil chemical properties between the margin and the forest.(3)Soil organic matter,available pHospHorus,ammonium nitrogen,total pHospHorus and soil pH can significantly affect the natural regeneration of forest margin.The increase of soil organic matter,available pHospHorus,ammonium nitrogen,total pHospHorus content and the decrease of pH value are beneficial to the regeneration of Larix gmelinii forest margin.There is a significant positive correlation between pHotosynthetic effective radiation,air temperature and forest margin regeneration,and air humidity and forest margin regeneration.There is not a significant negative correlation between edge regeneration,that is,the increase of pHotosynthetic active radiation and air temperature are beneficial to the edge regeneration of Larix gmelinii forest;the main factors affecting edge regeneration of Larix gmelinii forest are soil organic matter,soil moisture content and pHotosynthetic active radiation.