Hurricanes fertilize mangrove forests in the Gulf of Mexico (Florida Everglades, USA)
Hurricanes fertilize mangrove forests in the Gulf of Mexico (Florida Everglades, USA)
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DOI：
10.1073/pnas.1908597117
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发表时间：
2020-03-03
影响因子：
11.1
通讯作者：
Hiatt, Matthew
中科院分区：
文献类型：
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作者：
Castaneda-Moya, Edward;Rivera-Monroy, Victor H.;Hiatt, Matthew
飓风是沿海地区反复出现的高能扰动，改变了红树林湿地的群落结构和功能。然而，大多数评估飓风对红树林影响的研究都侧重于负面影响，而没有考虑飓风引起的沉积物沉积和相关的营养施肥对红树林生产力和复原力的积极影响。在这里，我们量化了2017年9月飓风伊尔玛穿越佛罗里达沿海沼泽地后如何影响土壤养分库，垂直增长和植物磷（P）吸收。厄玛沉积物的垂直吸积比长期（100年）年吸积率（0.27 +/- 0.04 cm y（-1））大6.7至14.4倍。风暴沉积物从墨西哥湾向内陆延伸了10公里。总P（TP）输入量在河口处最高，P浓度是下垫面（顶部10 cm）土壤的两倍（0.19 +/- 0.02 mg cm（-3））。这种P沉积贡献了49%至98%的土壤养分库。因此，所有红树林物种在2018年初，Irma影响后3个月，凋落物叶TP和土壤孔隙水无机P浓度显着增加，从而强调了营养吸收的物种间差异。与东南部地区相比，西南部红树林占主导地位的河口的平均TP负荷率（94 +/- 13 kg ha（-1）d（-1））高出5倍，突出了飓风作为影响森林生产力的自然施肥机制的积极作用。由飓风沉积的富含磷的矿物沉积物创造了有利于森林快速恢复的遗产，刺激了泥炭土的发育，并对海平面上升具有复原力。
Hurricanes are recurring high-energy disturbances in coastal regions that change community structure and function of mangrove wetlands. However, most of the studies assessing hurricane impacts on mangroves have focused on negative effects without considering the positive influence of hurricane-induced sediment deposition and associated nutrient fertilization on mangrove productivity and resilience. Here, we quantified how Hurricane Irma influenced soil nutrient pools, vertical accretion, and plant phosphorus (P) uptake after its passage across the Florida Coastal Everglades in September 2017. Vertical accretion from Irma's deposits was 6.7 to 14.4 times greater than the long-term (100 y) annual accretion rate (0.27 +/- 0.04 cm y(-1)). Storm deposits extended up to 10-km inland from the Gulf of Mexico. Total P (TP) inputs were highest at the mouth of estuaries, with P concentration double that of underlying surface (top 10 cm) soils (0.19 +/- 0.02 mg cm(-3)). This P deposition contributed 49 to 98% to the soil nutrient pool. As a result, all mangrove species showed a significant increase in litter foliar TP and soil pore-water inorganic P concentrations in early 2018, 3 mo after Irma's impact, thus underscoring the interspecies differences in nutrient uptake. Mean TP loading rates were five times greater in southwestern (94 +/- 13 kg ha(-1) d(-1)) mangrove-dominated estuaries compared to the southeastern region, highlighting the positive role of hurricanes as a natural fertilization mechanism influencing forest productivity. P-rich, mineral sediments deposited by hurricanes create legacies that facilitate rapid forest recovery, stimulation of peat soil development, and resilience to sea-level rise.