文献类型：期刊文献

英文题名：Spatial patterns and seasonal dynamics of foliar nutrients in 5-year-old Betula alnoides plantations

作者：Wang, Chunsheng[1] Guo, Junjie[1] Zhao, Zhigang[1] Wang, Huan[1] Zeng, Jie[1]

第一作者：王春胜

通信作者：Zeng, J[1]

机构：[1]Chinese Acad Forestry, Res Inst Trop Forestry, Guangzhou 510520, Peoples R China

年份：2021

卷号：480

外文期刊名：FOREST ECOLOGY AND MANAGEMENT

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000599342600009)】；

基金：This work was supported by the National Natural Science Foundation of China [grant number 31600501] and the National Key Research and Development Program of China [grant number 2016YFD0600604]. The authors thank Yunan Forest Farm for providing the experimental site.

语种：英文

外文关键词：Macronutrients; Crown layer; Nutrient dynamics; Retranslocation; Resorption; Planting density

摘要：Spatial distribution and season-induced variations in foliar nutrients of tree crowns play key roles in growth, and nutrient retranslocation and resorption from leaves are important mechanisms for trees to cope with sites of diversified fertility. Seasonal dynamics and spatial patterns of foliar macronutrients (Nitrogen (N), Phosphorus (P) and Potassium (K)) as well as nutrient retranslocation and resorption in a series of crown layers were examined in 5-year-old Betula alnoides plantations using a spacing trial (2500 (2 m x 2 m, spacing), 1667 (2 m x 3 m), 1250 (2 m x 4 m), 1111 (3 m x 3 m), 833 (3 m x 4 m) and 625 (4 m x 4 m) stems.ha? 1) in south China. Significant effects of planting density on foliar nutrient concentrations and nutrient retranslocation and resorption were absent during a whole seasonal cycle or in each season. Both foliar total P and K concentrations increased significantly with increasing crown depth, whereas an obvious trend was not observed for foliar total N concentration. The season with the lowest foliar nutrient concentration varied with the elements, i.e. summer (Jul) for N, winter (Jan) for P and spring (Apr) for K, whereas the highest was observed in autumn (Oct) for all these macronutrient elements. Among crown layers, differences in nutrient concentrations were much lower in the high growth seasons from October to April than those in other seasons. There were significant differences among crown layers in N and P retranslocation efficiency rather than in nutrient resorption efficiency. Significant differences were absent in both retranslocation and resorption efficiencies of K. The highest nutrient retranslocation efficiency was found in the crown layer 2-3 m above ground level for N and 3-4 m for P. The absence of considerable differences among spacing treatments and crown layers mentioned above might be due to the weak early intra-specific competition induced by planting density, soil fertility or fertilization and nutrient demands of this species. These findings could provide suggestions for implementing proper pruning treatments, improving fertilization regimes and other related forest managements for B. alnoides and even other valuable timber species in the tropical and warm sub-tropical regions. Superscript/Subscript Available