Field vegetation dataset: Mangrove expansion on the low wooded islands of the Great Barrier Reef

Mangrove forests are the dominant vegetation growing on low wooded islands, which occur in the Caribbean, Indian and Pacific Oceans. In the northern Great Barrier Reef, we map remarkable, undocumented mangrove forest extension on ten low wooded islands in the Howick Group that collectively equates to an area of 667, 000 m^2 (66.7 ha). We combine extensive field survey with canopy height models derived from RPA imagery and allometric scaling to quantify above ground biomass in both old (pre-1973) and new (post-1973) forest areas. Forest expansion added ~ 10,233 tonnes of new biomass since the early 1970s. Such substantial expansion of mangrove forest has occurred within a short time span in response to changing environmental controls. These include sea-level rise, sediment transport and deposition, cyclone impact and the development of associated reef flat sedimentary landforms, including unconsolidated and lithified shingle ridges, which influence reef flat hydrodynamics. Our observatio..., Rapid in-situ mangrove community surveys were conducted at seven of the ten reef sites visited in the Howick Islands from the 1st – 11th June 2021 (Table S1). Surveys collected information on species composition, structure and health status of individual trees; and plot-scale vegetation metrics for development of setting-specific biomass scaling models. Fifteen shore-normal belt transect survey sites were planned using the 1973 mangrove forest maps combined with recent satellite imagery to ensure a diverse range of mangrove age classes (i.e. pre- and post- 1973 establishment) and species assemblages were assessed.
Transect start points were located using a real-time Kinematic GPS with satellite RTX correction (Trimble R10; Trimble Inc. USA) with expected horizontal and vertical uncertainties of ~2cm and ~5cm respectively. Transect orientation was measured with a hand-held compass. See supplementary Figure S1 for the location of in-situ mangrove biomass surveys.
Transects ranged in lengt..., , # Field vegetation dataset - Mangrove expansion on the low wooded islands of the Great Barrier Reef

[https://doi.org/10.5061/dryad.7h44j1012](https://doi.org/10.5061/dryad.7h44j1012)

In the northern Great Barrier Reef, we map remarkable, undocumented mangrove forest extension on 10 low wooded islands in the Howick Group that collectively equates to an area of 667 000 m2 (66.7 ha). We combine extensive field survey with canopy height models derived from RPA imagery and allometric scaling to quantify above ground biomass in both old (pre-1973) and new (post-1973) forest areas. Forest expansion added approximately 10,233 tonnes of new biomass since the early 1970s. We suggest that such substantial expansion of mangrove forest has occurred within a short time span in response to changing environmental controls. These may include sea-level rise, sediment transport and deposition, cyclone impact, and the development of associated reef flat sedimentary landforms including unconsolidated and ...,

红树林是分布于加勒比海、印度洋及太平洋海域低矮木质岛屿上的优势植被。在大堡礁北部区域，我们对豪威克群岛（Howick Group）中的10座低矮木质岛屿上此前未被记载的显著红树林扩张区域进行了制图，其总面积达667000平方米（66.7公顷）。我们结合大规模野外调查、由遥控航空平台（RPA）影像生成的冠层高度模型，以及异速生长缩放（allometric scaling）方法，对1973年以前形成的成熟林与1973年之后形成的新生林的地上生物量进行了量化。自20世纪70年代初以来，此次森林扩张新增了约10233吨生物量。此类大规模红树林扩张在短时间尺度内发生，是对环境调控因子变化的响应，这些因子包括海平面上升、泥沙输运与沉积、气旋影响，以及相关礁坪沉积地貌的发育——其中包含影响礁坪水动力条件的未固结与岩化砾石脊。我们的观测……，2021年6月1日至11日，我们在豪威克群岛调研的10个礁坪站点中的7个开展了快速原位红树林群落调查（详见补充材料表S1）。此次调查记录了单株树木的物种组成、结构与健康状况，以及样地尺度的植被指标，用于构建针对研究生境的专属生物量缩放模型。我们结合1973年红树林森林分布图与近期卫星影像，规划了15条垂直于岸线的带状样带调查站点，以确保覆盖不同年龄层级（即1973年前后定植的红树林）与物种组合的样地。
样带起始点通过搭载卫星RTX校正（RTX Correction）的实时运动学GPS（Real-time Kinematic GPS，型号为Trimble R10，美国天宝公司（Trimble Inc.））进行定位，其预期水平与垂直定位不确定度分别约为2厘米与5厘米。样带方位通过手持罗盘进行测量。原位红树林生物量调查的点位分布详见补充材料图S1。
样带长度……，# 野外植被数据集——大堡礁低矮木质岛屿的红树林扩张

[https://doi.org/10.5061/dryad.7h44j1012](https://doi.org/10.5061/dryad.7h44j1012)

在大堡礁北部区域，我们对豪威克群岛（Howick Group）中的10座低矮木质岛屿上此前未被记载的显著红树林扩张区域进行了制图，其总面积达667000平方米（66.7公顷）。我们结合大规模野外调查、由遥控航空平台（RPA）影像生成的冠层高度模型，以及异速生长缩放（allometric scaling）方法，对1973年以前形成的成熟林与1973年之后形成的新生林的地上生物量进行了量化。自20世纪70年代初以来，此次森林扩张新增了约10233吨生物量。我们认为此类大规模红树林扩张在短时间尺度内发生，是对环境调控因子变化的响应，这些因子包括海平面上升、泥沙输运与沉积、气旋影响，以及相关礁坪沉积地貌的发育，其中包含未固结与……