Marler Thomas E, Cruz Gil N
Bagong Kaalaman Botanikal Institute, 15 Rizal Street, Barangay Malabañas, Angeles City 2009, Philippines.
Western Pacific Tropical Research Center, University of Guam, Mangilao, GU 96923, USA.
Plants (Basel). 2022 Sep 3;11(17):2310. doi: 10.3390/plants11172310.
Trees contribute to ecosystem nutrient cycling through the amount, timing, and composition of litterfall. Understanding the nature of this contribution from endangered tree species may aid in species and habitat recovery efforts. Serianthes nelsonii is an endangered tree species from the Mariana Islands, and little is known about litterfall dynamics. The timing of leaf, fruit, and stem litterfall was determined to more fully understand the return of nutrients via litter. The total annual litterfall was 272.8 g·m−2, with 45% represented by leaves, 48% represented by stems, and 7% represented by fruits. Stem litterfall weight contrasted more from month to month than the other organs, and leaf litterfall exhibited the most even distribution throughout the year. The timing of fruit and stem litterfall was influenced by the timing of extreme wind events. Leaf litter contributed nutrients in the following order: carbon > calcium > nitrogen > potassium > magnesium > iron > phosphorus > manganese > boron > zinc > copper. Fruit and stem litter contributed nutrients in the following order: carbon > calcium > nitrogen > magnesium > potassium > phosphorus > iron > manganese > boron > zinc > copper. Based on carbon/nitrogen, the stem litter exhibited the lowest quality and leaf litter exhibited the highest quality for speed of nutrient release via decomposition. Conservationists may use this knowledge to more fully integrate S. nelsonii trees into habitat management plans.
树木通过凋落物的数量、时间和组成对生态系统养分循环做出贡献。了解濒危树种这种贡献的性质可能有助于物种和栖息地的恢复工作。尼尔森银钟树是一种来自马里亚纳群岛的濒危树种，人们对其凋落物动态知之甚少。确定叶片、果实和茎干凋落物的时间，以便更全面地了解养分通过凋落物的归还情况。年总凋落物量为272.8克·平方米，其中叶片占45%，茎干占48%，果实占7%。茎干凋落物重量每月的变化比其他器官更大，而叶片凋落物全年分布最为均匀。果实和茎干凋落物的时间受极端风事件时间的影响。叶片凋落物贡献养分的顺序为：碳>钙>氮>钾>镁>铁>磷>锰>硼>锌>铜。果实和茎干凋落物贡献养分的顺序为：碳>钙>氮>镁>钾>磷>铁>锰>硼>锌>铜。基于碳/氮比，就通过分解释放养分的速度而言，茎干凋落物质量最低，叶片凋落物质量最高。保护主义者可以利用这些知识，将尼尔森银钟树更全面地纳入栖息地管理计划。
