林地生长数据 Forest Growth Data
图1. 林地中杨树生长数据
Image 1. Poplars' Growth Data
图2. 林地中松树生长数据
Image 2. Pines' 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2022年度2012-5、2012-6、2012-8由于疫情影响，无法抵达，未进行测量。林地数据主体为2012-1、2012-2、2012-3、2012-4、2012-7五块林地。其整体保存率为69.39%。
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 2012-8 forest sites couldn’t be reached because of the pandemic control policy in 2022. These three sites were excluded in the survey. The statistics came from the survey on 2012-1, 2012-2, 2012-3, 2012-4 and 2012-7 forest sites. The overall survival rate of these forests was 69.39%. 该林地位置相对偏远，内部地势复杂，造成其栽植和抚育存在一定的难度。林地的保存情况较差，杨树和樟子松在栽植前三年的成活情况不稳定，起伏较大，之后逐渐稳定。杨树基本维持在60%左右，樟子松较差，保存情况不足50%。 The plot is located in a remote area with complicated terrain, which results in the difficulty for tree planting and maintenance. The overall preservation condition is in need of improvement, poplars and pines are in an unstable condition in the first three years, but gradually stabilized afterwards regarding the growth condition. Generally speaking, poplars basically sustain a 60% preservation rate, however, pines are even less than 50%. 2022年度的树高均值均相较于2019年发生了显著的增长，但杨树的树高均值依旧偏低，不足5米，不符合杨树快速生长的特点。樟子松的生长相对正常，单位年份的增幅相较于往年的30-50cm，有了较大的提升，但要判断林地内的樟子松是否进入快速生长期，依旧需要继续观察。杨树和樟子松的地径、胸径均值都发生了较大增长，林地内存活林木在不断生长，但同时生长状态的差异在扩大。 The average height in 2022 was increasing significantly compared to 2019. But the average height was still low, below 5 meters, which didn’t not reach the standard of fast-growing poplars. The pines grew more naturally, and the increasing range was bigger than previous years, which used to be 30 to 50 cm. Further observation is needed to determine whether the pines entered their fast-growing phase. The basal diameter and DBH of both the poplars and pines were growing significantly, meaning that the trees inside the site were continuously growing. The difference in their growth were expanding. 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。其对比如下。从测量胸径的比例也能够看出，杨树表现出明显的灌木化，高于1.3米的树数量在增加，但占比过低。而樟子松的比例基本固定了，说明樟子松低矮苗木很难继续生长，林地差异化显著。 The DBH is measured at the 1.3-meter-high point of tree trunk. The percentage of trees reaching 1.3-meter-high is the key factor for DBH measurements, as showed below. The percentage also showed poplars had the tendency of becoming brushes. Although some poplars were growing above 1.3 meters, but the percentage among all the trees was still low. The percentage of pines remained the same, so the short pines could hardly grow in the future. The differences among the trees were significant.
图3. 胸径地径均值变化
Image 3 Basal diameter and DBH of the forest site over years
图4. 胸径测量比例变化
Image 4. The percentage of measurable DBH over years
林地情况说明 Forest Description
图5&6&7树行航拍和地面照片（2022年9月26日）
Image 5&6&7， Long shot and close shot of tree rows2. Significant difference among poplars, taken on September 26, 2022
