Florida mangrove diebacks@en

Multi-proxy data on sediment cores MD-1 (26° 24' 43.6598 N, 81° 52' 21.2388 W, 70 cm) and MD-3 (26° 22' 08.9963 N, 81° 51' 13.5940 W, 60 cm depth) acquired via an aluminum push corer from southwest Florida coast with tidal flats were obtained to determine the cause(s) of mangrove death. These data involves planialtimetric and stratigraphic analyzes, implemented in two phases: 1) Selection of degraded mangrove areas for a topographic survey based on laser/GNSS data and aerophotogrammetry of drone images, and determination of the stature and species of mangrove trees (Dieback location.jpg, Table 1); 2) Selection of the core sampling sites for a paleoenvironmental reconstruction on a decadal and century time scale (Table 2 and 3; Pollen MD-3-1, Isotope, CHD 1-3 Loi&XRF (MD-1), CHD 2-2 LOI&XRF; Grain size MD-3-1). A Drone DJI Phantom 4 Advanced recorded ~1421 high spatial resolution photos (2.6 cm) by a digital 4K/20MP (RGB) camera to cover ~158 ha in Nov/2019, following predetermined missions (90º camera angle, 90% frontal, and 75% lateral overlay, at 100 m altitude). Planialtimetric data (coordenates of Ground Control Points) were obtained by drone aerophotogrammetry using the Agisoft Metashape Professional version 1.8.4 (Table 1). Radiocarbon dates (Table 2) were obtained by accelerator mass spectrometry (AMS) at the Center for Applied Isotope Studies (UGAMS) of the University of Georgia and International Chemical Analysis, Inc. Radiocarbon ages were normalized to a δ13C of −25‰ VPDB and reported as calibrated years (calibrated years before the present; 2σ) using CALIB 8.2 (Stuiver et al., 2017). To obtain pollen data, sediment samples were treated following standard pollen analytical techniques (Faegri & Iversen, 1989)(Pollen M3-3-1). Pollen and spore classification, with at least 300 pollen grains identified for each sample, was based on reference collections of the LSU Global Paleoecology Laboratory, Laboratory of Coastal Dynamics – UFPA, 14C Laboratory of the Center for Nuclear Energy in Agriculture (CENA/USP), and various pollen keys (Markgraf & D'Antoni, 1978; Roubik & Moreno, 1991). Sediments were sampled at 2 cm intervals (0.5 g) to quantify sediment particle size in a laser diffraction particle size analyzer (SHIMADZU SALD 2101) at the Laboratory of Coastal Dynamics - Federal University of Pará (UFPA) (Grain size MD-3-1). […]为明确红树林死亡的成因，本研究获取了采自佛罗里达西南海岸潮滩的两根沉积物岩芯MD-1（26°24′43.6598″N，81°52′21.2388″W，岩芯总长70 cm）与MD-3（26°22′08.9963″N，81°51′13.5940″W，岩芯总长60 cm）的多代用指标数据，岩芯采集采用铝制推入式岩芯采样器完成。本数据集涵盖平面高程与地层分析工作，分为两个阶段开展： 1. 基于激光/全球导航卫星系统（GNSS）数据与无人机影像航空摄影测量结果，选取退化红树林区域开展地形测量，并测定红树林的树高与树种（对应资料：Dieback location.jpg、表1）； 2. 选取岩芯采样点位，开展十年至百年尺度的古环境重建工作（对应资料：表2、表3；指标包括MD-3-1孢粉数据、同位素数据、MD-1的CHD 1-3烧失量（LOI）与X射线荧光光谱（XRF）数据、CHD 2-2 LOI与XRF数据，以及MD-3-1粒度数据）。 2019年11月，研究团队使用DJI Phantom 4 Advanced无人机搭载4K/2000万像素（RGB）数码相机，按照预设飞行任务（飞行高度100 m、相机倾角90°、航向重叠率90%、旁向重叠率75%）完成了约158公顷区域的航拍，共获取约1421张空间分辨率达2.6 cm的高清照片。平面高程数据（地面控制点坐标）通过Agisoft Metashape Professional 1.8.4版软件开展无人机航空摄影测量获取（表1）。 放射性碳定年数据（表2）由佐治亚大学应用同位素研究中心（UGAMS）与国际化学分析公司（International Chemical Analysis, Inc.）采用加速器质谱（AMS）方法完成测定。所有放射性碳年龄均归一化至δ¹³C为-25‰ VPDB（维也纳佩尔迪北溪标准），并采用CALIB 8.2软件（Stuiver等，2017）校准为距今年份（校准前距今年份；2σ置信区间）。 为获取孢粉数据，研究团队按照标准孢粉分析流程（Faegri & Iversen，1989）对沉积物样品进行前处理（对应样品：Pollen M3-3-1）。每份样品至少计数300粒花粉以完成孢粉与孢子鉴定，鉴定依据包括路易斯安那州立大学（LSU）全球古生态学实验室、帕拉联邦大学海岸动力学实验室、圣保罗大学农业核能中心（CENA/USP）的孢粉标本库，以及多部孢粉鉴定手册（Markgraf & D'Antoni，1978；Roubik & Moreno，1991）。 沉积物样品以2 cm为间隔采集（每份约0.5 g），于帕拉联邦大学海岸动力学实验室采用激光衍射粒度分析仪（岛津SHIMADZU SALD 2101）完成粒度分析（对应样品：Grain size MD-3-1）。[……]