Data from: Allocation strategies for nitrogen and phosphorus in forest plants

The allocation of limiting elements, such as nitrogen (N) and phosphorus
(P), in plants is an important basis for structural stability and
functional optimization in natural plant communities. However, because of
the lack of systematic investigation data, the mechanisms of optimal
nutrient allocation in plants in natural forests are still unclear. Using
consistent measurements of N and P contents in 930 plant species, we
explored the allocation strategies for N and P in different plant organs
and plant functional groups (PFGs) in natural communities. The N and P
contents and N:P ratio were the highest in the leaf (the most active
organ) at the organ level. At the PFG level, the N and P contents were
higher in herbs than in woody plants, but the trend was opposite for the
N:P ratio. The elemental plasticity of root was higher than that of leaf.
Furthermore, at the large scale, the allometric exponents of N and P were
less than 1 and showed no difference, indicating strong conservatism of
the scaling relationship in plants. In summary, higher element content in
more active organs, higher element plasticity in underground organs, and
conservative allometric allocation among different organs and among
different PFGs jointly constitute the optimal strategies for the
allocation of limiting elements.

植物体内限制性元素（如氮（N）、磷（P））的分配格局，是自然植物群落维持结构稳定与实现功能优化的重要基础。然而，由于缺乏系统性调查数据，天然林植物最优营养分配的内在机制仍未明晰。本研究通过对930种植物的氮、磷含量开展统一标准化测定，探究了自然群落中不同植物器官以及植物功能群（Plant Functional Groups, PFGs）内的氮磷分配策略。在器官尺度上，叶片作为植物最活跃的器官，其氮、磷含量及氮磷比均为最高。在植物功能群尺度上，草本植物的氮、磷含量均高于木本植物，但氮磷比的变化趋势恰好相反。根系的元素可塑性显著高于叶片。进一步而言，在大尺度下，氮与磷的异速生长指数均小于1且无显著差异，表明植物元素缩放关系具有较强的保守性。综上，活跃器官中更高的元素含量、地下器官中更强的元素可塑性，以及不同器官与不同植物功能群间保守的异速分配模式，共同构成了限制性元素分配的最优策略。