Chen Ke-Yi, Zhang Hui-Ru, Zhang Bo, He You-Jun
Research Institute of Forestry Policy and Information, Chinese Academy of Forestry, Beijing 100091, China.
Research Institute of Forest Resources Information Techniques, Chinese Academy of Forestry, Beijing 100091, China.
Ying Yong Sheng Tai Xue Bao. 2021 Aug;32(8):2745-2754. doi: 10.13287/j.1001-9332.202108.003.
To reveal the community succession rule of natural secondary forest, we investigated basic characteristics and coordinates of each tree (DBH≥1 cm) within a plot (100 m×100 m) using the adjacent grid method and examined the distribution pattern and spatial associations of dead woods in a natural spruce-fir secondary forest in Jingouling Forest Farm, Wangqing Forestry Bureau, Jilin Province, China. The results showed that the diameter class distribution of dead woods showed the pattern of left single-peak curve, while the logs showed the pattern of multi-peak curve. The relationship between the abundance of dead woods and the standing individuals of a particular species was inconsistent. There was a significant negative exponential relationship between the number of dead woods and mixing degree of trees. The distribution of dead woods was concentrated at the 0-8 m scale. With the increases of scale, it gradually changed to random or uniform, with the random distribution being dominant. The aggregation distribution of dead woods with middle (10 cm≤DBH＜20 cm) and small (1 cm≤DBH＜10 cm) DBH was the main reason for the aggregation distribution of dead woods at small scale below 8 m. The spatial associations between dead woods and stan-ding trees at different diameter classes were significantly different. The relationship between dead woods and saplings (1 cm≤DBH＜5 cm) was closely correlated. The dead woods with large DBH and saplings showed a significant positive association at 2-25 m scale. There was no spatial association between dead woods and small trees (5 cm≤DBH＜15 cm). At the 0-3 m scale, there was a positive association between the middle trees (15 cm≤DBH＜25 cm) and dead woods of small and middle DBH. At the 9, 11-14 and 15, 42-45 m scales, dead woods of small and middle DBH were significantly negatively associated with large trees (DBH≥25 cm). In conclusion, biological traits, diameter class distribution, and spatial distribution affected the abundance and diameter class distribution of dead woods. The species with low mixing degree tended to have more dead woods. The diameter and scale would affect the spatial distribution of dead woods. The spatial correlation between dead woods and standing trees varied across diameter classes and scales.
为揭示天然次生林群落演替规律，我们采用相邻网格法调查了吉林省汪清林业局金沟岭林场天然云冷杉次生林中一个样地（100 m×100 m）内每株胸径≥1 cm树木的基本特征和坐标，并研究了枯立木的分布格局和空间关联性。结果表明，枯立木的径级分布呈左单峰曲线格局，而原木呈多峰曲线格局。枯立木的数量与特定物种的现存个体之间的关系不一致。枯立木数量与树木混交度之间存在显著的负指数关系。枯立木的分布集中在0 - 8 m尺度。随着尺度增加，其逐渐转变为随机或均匀分布，以随机分布为主。中径（10 cm≤胸径＜20 cm）和小径（1 cm≤胸径＜10 cm）枯立木的聚集分布是8 m以下小尺度枯立木聚集分布的主要原因。不同径级的枯立木与现存树木之间的空间关联性显著不同。枯立木与幼树（1 cm≤胸径＜5 cm）的关系密切相关。大径级枯立木与幼树在2 - 25 m尺度上呈显著正关联。枯立木与小树（5 cm≤胸径＜15 cm）之间不存在空间关联。在0 - 3 m尺度上，中径树（15 cm≤胸径＜25 cm）与小径和中径枯立木呈正关联。在9、11 - 14以及15、42 - 45 m尺度上，小径和中径枯立木与大树（胸径≥25 cm）呈显著负关联。总之，生物学特性、径级分布和空间分布影响了枯立木的数量和径级分布。混交度低的物种往往有更多的枯立木。直径和尺度会影响枯立木的空间分布。枯立木与现存树木之间的空间相关性随径级和尺度的不同而变化。
