Effects of environmental variables on seedling distribution of rare and endangered Dacrydium pierrei

• Main Authors: Wu Chunyan, Chen Yongfu, Chen Qiao, Wang Wenquan, Hong Xiaojiang, Han Wentao, Li Xiaocheng
• Format: Article
• Language: English
• Published: De Gruyter 2017-11-01
• Series: Open Life Sciences
• Subjects: environment; seedling-sapling; soil moisture; pca; gmm; dacrydium pierrei
• Online Access: https://doi.org/10.1515/biol-2017-0040

Because growth environment is affected by climate change, Dacrydium pierrei resources are becoming less and less. Therefore, understanding the effects of environmental variables on seedling-sapling distributions can help gain insight into changes in population recruitment in the context of climate change. The seedling-saplings distribution and variability of Dacrydium pierrei in environmental variables at Bawangling, Hainan, China, was surveyed over a 3-year period. In addition, laboratory experiments measuring the effects of soil moisture on seedling emergence were conducted to identify seedling development characteristics; principal component analysis (PCA) and Gaussian mixture model (GMM) were used to assess how different factors influenced Dacrydium pierrei seedlings-saplings distribution. The results demonstrated that the influence degree of seedling-sapling distribution is soil temperature>litter thickness>available phosphorus>canopy density> available potassium>nitrate nitrogen; a large number of seedling-saplings occurring at altitudes 1140-1300 m; a GMM trained with a C2-L3-H4-A5-I6 combination yielded an accuracy of 72.23% in simulating seedling-saplings distribution; temperature and precipitation have strong impact on seedling-sapling distribution, with increasing soil moisture, seedling emergence shows a positive relationship. This study focuses more on developing a new method for research on the seedling-sapling distribution of Dacrydium pierrei to get reference for its adaptive management with the intense extreme climate change.