Species richness patterns and the determinants of larch forests in China

• Published in: Plant diversity 2022-09, Vol.44 (5), p.436-444
• Main Authors: Fang, Wenjing, Cai, Qiong, Zhao, Qing, Ji, Chengjun, Zhu, Jiangling, Tang, Zhiyao, Fang, Jingyun
• Format: Article
• Language: English
• Subjects: Biodiversity; Community structure; Determinants; Geographic pattern; Larch forest; Species richness
• ISSN: 2468-2659; 2468-2659
• DOI: 10.1016/j.pld.2022.05.002

Larch forests are important for species diversity, as well as soil and water conservation in mountain regions. In this study, we determined large-scale patterns of species richness in larch forests and identified the factors that drive these patterns. We found that larch forest species richness was high in southern China and low in northern China, and that patterns of species richness along an elevational gradient depend on larch forest type. In addition, we found that patterns of species richness in larch forests are best explained by contemporary climatic factors. Specifically, mean annual temperature and annual potential evapotranspiration were the most important factors for species richness of tree and shrub layers, while mean temperature of the coldest quarter and anomaly of annual precipitation from the Last Glacial Maximum to the present were the most important for that of herb layer and the whole community. Community structural factors, especially stand density, are also associated with the species richness of larch forests. Our findings that species richness in China's larch forests is mainly affected by energy availability and cold conditions support the ambient energy hypothesis and the freezing tolerance hypothesis. •Species richness varied significantly among different larch forest types in China.•Species richness of larch forests showed distinct latitudinal and elevational patterns, and elevational patterns were influenced by larch forest types.•The most dominant drivers of patterns of species richness in larch forests in China are contemporary climatic factors.•Our results support the ambient energy hypothesis and the freezing tolerance hypothesis for species richness.