林地生长数据 Forest Growth Data
图1. 林地生长数据
Image 1. Forest growth data
林地目前保存率相对稳定，基本维持在一个较好的水平。林地初植期杨树的生长存在一定程度的不稳定性，树高、地径、胸径等指标容易受到林间农作的影响。树高均值的绝对值和增幅相较同年份的其他杨树林偏低，这主要是受初值密度过高、树种差异、土壤养分等多种因素影响。树高均值在2023年度保持上升，说明从整体趋势上，林地依旧处于生长期。
The current survival rate of forest was relatively stable, basically maintaining a good level.The growth of poplars in the early stage of planting was usually unstable, and the indicators were easy to be affected by the interplanting, such as height, basal diameter, diameter at breast height(DBH). The absolute value and increasing range of height of this forest site were both lower than the other sites which were planted in the same year. This was caused by a combination of factors including the high density of planting in the beginning, the different type of poplar saplings, the soil nutrition etc. The average height of trees continued to increase in 2023, showing that the forest was still in the growing phase. 林地平均胸径和地径在2023年度继续增长。胸径的测量的位置在树干1.3米高度处，苗木达到1.3米高度的比例是影响胸径变化的重要因素。可测量比例的变化较小，保持在75%左右，说明该比例为上限，林地相对稳定。 The average basal diameter and DBH of trees continued to increase in 2023. The DBH was measured at 1.3-meter-high of the tree trunk. The percentage of trees reaching 1.3 meter was the key factor for the variations of DBH. The percentage of measurable trees maintained around 75%, which should be the upper limit. Overall, the forest was in a stable status.
图2. 胸径地径均值变化
Image 2 Basal diameter and DBH of the forest site over years
图3. 胸径测量比例变化
Image 3. The percentage of measurable DBH over years
林地情况说明 Forest Description
图4. 林地近景，2023.10.20
Image 4. Close shot of the forest, October 20, 2023
