Lin Xiao-Yu, Wan Xiao-Hua, Jia Hui, Huang Zhi-Qun, Zou Bing-Zhang, Wang Si-Rong
1 School of Geographical Sciences, Fujian Normal University, Fuzhou 350117, China.
2 Key Laboratory for Humid Subtropical Eco-Geographical Processes of Ministry of Education, Fujian Normal University, Fuzhou 350117, China.
Ying Yong Sheng Tai Xue Bao. 2024 Jun;35(6):1455-1462. doi: 10.13287/j.1001-9332.202406.006.
The contribution of litterfall nutrient return to the maintenance of soil carbon pool and nutrient cycling is a crucial aspect of forest ecosystem functioning. Taking 21 tree species in subtropical young plantations as subjects, we investigated the correlation between litterfall nutrient return characteristics and functional traits of leaf and root and. The results showed notable variations in litterfall production, standing crop, and nutrient return across all the examined tree species. exhibited the highest litterfall production (689.2 g·m·a) and standing crop (605.1 g·m), while demonstrated the lowest litterfall production (36.0 g·m·a) and standing crop (10.0 g·m). The nitrogen and phosphorus return amounts of 21 species ranged from 3.0 to 48.3 kg·hm and from 0.1 to 2.0 kg·hm, respectively. demonstrated the highest nitrogen return, while exhibited the highest phosphorus return. had the lowest nitrogen and phosphorus return. Results of the stepwise regression analysis indicated that litterfall production exhibited a significant negative correlation with leaf nitrogen content and leaf dry matter content, and a significant positive correlation with fine root tissue density. Additionally, leaf nitrogen content, leaf dry matter content, and specific root length had a significant negative impact on standing crop. The structural equation modelling results indicated that leaf dry matter content had a direct or indirect negative effect on nitrogen return amount through the reduction of litterfall production. Conversely, fine root tissue density had a significant positive impact on nitrogen return amount by increasing litter leaf nitrogen content. Both leaf nitrogen content and leaf dry matter content had direct or indirect negative effects on phosphorus return amount through the reduction of litterfall production. In conclusion, the tree species with low leaf nitrogen content and dry matter content, as well as high fine root tissue density, was recommended for the establishment of plantations in the subtropical zone in order to enhance nutrient cycling through litter decomposition and improve soil fertility and forest productivity.
凋落物养分归还对土壤碳库维持和养分循环的贡献是森林生态系统功能的一个关键方面。以亚热带幼龄人工林中的21个树种为研究对象，我们调查了凋落物养分归还特征与叶和根功能性状之间的相关性。结果表明，在所研究的所有树种中，凋落物产量、现存生物量和养分归还存在显著差异。[树种名称1]的凋落物产量最高（689.2 g·m⁻²·a⁻¹），现存生物量最高（605.1 g·m⁻²），而[树种名称2]的凋落物产量最低（36.0 g·m⁻²·a⁻¹），现存生物量最低（10.0 g·m⁻²）。21个树种的氮和磷归还量分别在3.0至48.3 kg·hm⁻²和0.1至2.0 kg·hm⁻²之间。[树种名称3]的氮归还量最高，而[树种名称4]的磷归还量最高。[树种名称5]的氮和磷归还量最低。逐步回归分析结果表明，凋落物产量与叶片氮含量和叶片干物质含量呈显著负相关，与细根组织密度呈显著正相关。此外，叶片氮含量、叶片干物质含量和比根长对现存生物量有显著负面影响。结构方程模型结果表明，叶片干物质含量通过减少凋落物产量对氮归还量有直接或间接的负面影响。相反，细根组织密度通过增加凋落叶氮含量对氮归还量有显著的正面影响。叶片氮含量和叶片干物质含量都通过减少凋落物产量对磷归还量有直接或间接的负面影响。总之，为了通过凋落物分解增强养分循环、提高土壤肥力和森林生产力，建议在亚热带地区建立人工林时选择叶片氮含量和干物质含量低、细根组织密度高的树种。
