Dissertation Research: Consequences and Implications of Leaf-Level N Versus P Limitation

本研究主要关注氮磷这两种最广泛和最重要的限制养分对光合作用、森林生长和生态系统过程的影响和影响。研究人员建议在夏威夷群岛的一个非常明确和有限的年龄序列中确定叶片水平N与P限制的后果和含义。这些地点都是由单一树种主导的天然森林，具有非常恒定的环境条件，沿着这些环境条件进行的实验表明，N限制了年轻地点的生产，P限制了最老地点的生产。长期施肥试验正在这些地点进行，因此我们可以评估营养受限的样地以及消除氮或磷限制的后果。本研究的结果将与地下过程、林分特征和生态系统级养分循环的调查相结合，以更好地了解热带森林的动态。这些资料将对森林对变化的反应能力以及森林生态系统的恢复和管理产生重大影响。

9701899 Goldstein This proposed research focuses on the consequences and implications of leaf level nutrient limitation to photosynthesis, forest growth, and ecosystem processes caused by nitrogen versus phosphorus, the two most widespread and important limiting nutrients. The researchers propose to determine the consequences and implications of leaf level N versus P limitation in a very well-defined and constrained age sequence of sites in the Hawaiian Islands. The sites are all natural forests dominated by a single tree species, with remarkably constant environmental conditions, along which experiments have demonstrated that N limits production in young sites, and P limits the oldest site. Long-term fertilizer experiments are ongoing in these sites, so we can evaluate both nutrient-limited plots and the consequences of removing limitation by N or P. Results from this study will both augment and be integrated with investigations of belowground processes, stand-level characteristics, and ecosystem-level nutrient cycling to better understand tropical forest dynamics. Such information will have substantial implications for both the responsiveness of forests to change, and the restoration and management of forest ecosystems.