林地生长数据 Forest Growth Data

图1. 林地生长数据

Image 1. Growth data

2012年林地，共计造林434658棵，占地6269亩，是项目造林面积最大的年份。在2023年度2012-5、2012-6、2012-7由于道路积水，无法抵达，未进行测量。林地数据主体为2012-1、2012-2、2012-3、2012-4、2012-8五块林地。其整体保存率为69.39%。2012-8林地的保存情况较好，保存率小幅度上升，这主要是由于测量样点减少带来数据浮动。

In 2012, MTP planted 434,658 trees in total, covering an area of 418 hectares. 2012 was the year when MTP planted the most trees since the beginning of the program. The 2012-5, 2012-6 and 2012-7 forest sites couldn’t be reached because of road waterlogging in 2023. These three sites were excluded in the survey. The statistics came from the survey on 2012-1, 2012-2, 2012-3, 2012-4 and 2012-8 forest sites. The overall survival rate of these forests was 69.39%. The 2012-8 plot was maintained well. The survival rate increased a little in 2023, mainly due to the decrease of samples which led to the float of data.

图2. 树高均值变化

Image 2. The average tree heights over years

图3. 树高分布

Image 3. Tree height distribution

该林地栽植的是杨树，杨树是速生树种，生长速度较快。树高的增长显著，增幅相对固定，林地生长速度逐渐平稳。林地内的林木树高分布相对正常，大部分苗木的树高集中在均值周边，而且均值的数值较高。胸径和地径均值的逐年变化对比如下图。可以看到胸径和地径的均值的依旧保持增长，但增幅放缓。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。树高大于1.3米的比例基本保持稳定，低矮林木的比例很少，没有出现明显的灌木化。

The plot was planted with poplars only. Poplars, as fast-growing tree type, grew quickly. The tree height increased significantly, and the speed of increase was stabilized. The distribution of tree height was normal. Most tree heights were distributed around the average value. And the average value was high. The variation of average basal diameter and diameter at breast height (DBH) are shown in the below graph. The average basal diameter and DBH continued to grow and the speed of growth was slowing down. The diameter at breast height was measured at 1.3-meter-high point of the trunk. Reaching 1.3-meter high was the key factor for the variations of DBH. The percentage of poplars over 1.3 meter was very stable in high level, which meant the percentage of small trees was small. No obvious sign of trees turning to bushes found in the site.

图4. 胸径地径均值变化

Image 4. Basal diameter and DBH of the forest site over years

图5. 胸径测量比例变化

Image 5. The percentage of measurable DBH over years

林地情况说明 Forest Description

图6&7. 林地照片，2023.10.25

Image 6&7. Forest photo, October 25, 2023

杨树生长较健康，树行间枯落物积累较多，部分区域内部存在玉米间种，造成了部分区域杨树的机械性损伤。

Poplars grew very strong. Multiple layers of dead leaves and branches were cumulated between tree rows. There was interplanting of crops in the site, which caused some mechanic damage on the tree trunks.

林地赞助商列表 Forest Sponsor List