Temporal nitrogen dynamics in intensively managed loblolly pine early stand development

Forest production is strongly dependent on nutrient uptake; however, sustainable management of intensively managed plantations requires an improved understanding of this relationship when fertilization occurs frequently across short rotations. Here, we studied temporal nitrogen (N) concentration ([N]) and content (Nc) dynamics under different silvicultural practices (herbicide, fertilization, and planting density) throughout early loblolly pine (Pinus taeda) stand development (5 years). We describe relationships of [N] and Nc of different stand components (foliage, branches, stem, roots, and competing vegetation) with carbon and biomass. Our results demonstrate that [N] of perennial loblolly tissues do not respond to silvicultural practices and progressively decrease through development. While foliar [N] was most responsive to resource availability, it was not consistent across time. Controlling competing vegetation was crucial to promote the use of site resources by the crop tree and i...

林木生产高度依赖养分吸收；然而，对于短轮伐期内频繁施肥的集约化经营人工林，其可持续经营需更深入厘清养分吸收与林木生产之间的关联。本研究以火炬松（*Pinus taeda*）林分早期发育阶段（前5年）为研究对象，探究了不同营林措施（除草剂施用、施肥、造林密度）下的氮（nitrogen, N）浓度（nitrogen concentration, [N]）与氮（nitrogen, N）含量（nitrogen content, Nc）的时间动态变化。本研究分析了林分不同组分（叶片、枝条、树干、根系及竞争植被）的氮浓度、氮含量与碳含量及生物量之间的相关关系。研究结果显示，火炬松多年生组织的氮浓度不受营林措施影响，且随林分发育进程逐渐降低。尽管叶片氮浓度对资源可获得性的响应最为显著，但该响应随时间推移并不稳定。调控竞争植被对于促进目标林木对立地资源的利用至关重要，且i...