High Mortality for Rare Species Following Hurricane Disturbance in the Southern Yucatán
High Mortality for Rare Species Following Hurricane Disturbance in the Southern Yucatán
复制标题
尤卡坦州南部飓风扰动后稀有物种的高死亡率
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
H. Wilbur
中科院分区：
文献类型：
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作者：
K. Vandecar;D. Lawrence;D. Richards;L. Schneider;J. Rogan;B. Schmook;H. Wilbur
飓风是尤卡坦半岛自然扰动机制的重要组成部分，有可能改变森林结构和组成，但在该地区，物种水平对强风的反应的调查有限。研究了5级飓风（2007年8月21日飓风迪安）对尤卡坦南部干旱热带森林的影响，包括树木受损、死亡率和发芽情况。在飓风过后9-11个月，在25，000平方公里的研究区域内，根据风速和归一化植被指数（NDVI）变化等级分层的92个（500平方米）样地中评估了损失。 我们研究了生物的相对重要性（即，物种、大小和木材密度）和非生物（即，风速）因素，以更好地解释损坏的模式。总体死亡率较低（3.9%），然而，不太常见的物种（8.5%）的死亡率比28种常见物种（1.8%）高出四倍以上，表明对群落组成的直接选择性后果。不同物种的程度和类型的损害经历，与敏感性增加与树的直径和高度。木材密度仅在超过风暴强度临界阈值（风速≥210公里/小时）的地区影响损害模式。 虽然总体而言，损害的严重程度随着风速的增加，常见的沿海物种比分布在内陆更远的物种更能抵抗损害。我们的研究结果表明，频繁的飓风干扰所施加的选择性压力已经并将继续影响尤卡坦半岛森林的植物区系组成，有利于某些抗风物种。
Hurricanes are an important part of the natural disturbance regime of the Yucatán Peninsula with the potential to alter forest structure and composition, yet investigations of species‐level responses to severe winds are limited in this region. The effect of a category 5 hurricane (Hurricane Dean, 21 August 2007) on dry tropical forests across the southern Yucatán was examined with respect to tree damage, mortality, and sprouting. Damage was assessed 9–11 mo following the hurricane in 92 (500 m2) plots stratified by wind speed and normalized difference vegetation index (NDVI) change classes over a 25,000 km2 study area. We investigated the relative importance of biotic (i.e., species, size, and wood density) and abiotic (i.e., wind speed) factors to better explain patterns of damage. Overall mortality was low (3.9%), however, mortality of less common species (8.5%) was elevated more than fourfold above that of 28 common species (1.8%), indicating immediate selective consequences for community composition. Species varied in the degree and type of damage experienced, with susceptibility increasing with tree diameter and height. Wood density influenced damage patterns only in areas where a critical threshold in storm intensity was exceeded (wind speeds ≥210 km/h). Although overall, damage severity increased with wind speed, common coastal species were more resistant to damage than species distributed farther inland. Our findings suggest that selective pressure exerted by frequent hurricane disturbance has, and will, continue to impact the floristic composition of forests on the Yucatán Peninsula, favoring certain wind‐resistant species.