NASA数据集—— 2017 年 7 月和 2018 年 7 月期间从阿拉斯加育空-库斯科金（Y-K）三角洲高地苔原火灾历史梯度的 43 个地块收集的生态野外数据
NASA数据集—— 2017 年 7 月和 2018 年 7 月期间从阿拉斯加育空-库斯科金（Y-K）三角洲高地苔原火灾历史梯度的 43 个地块收集的生态野外数据
ABoVE: Vegetation Composition across Fire History Gradients on the Y-K Delta, Alaska
简介 文档修订日期：2020-05-15
数据集版本: 1
数据集摘要 本数据集提供了 2017 年 7 月和 2018 年 7 月期间从阿拉斯加育空-库斯科金（Y-K）三角洲高地苔原火灾历史梯度的 43 个地块收集的生态野外数据。地块级数据包括植被物种组成和结构、叶面积指数（LAI）、地形、解冻深度以及在 1971-1972 年、1985 年、2006-2007 年、2015 年烧毁的地块或未烧毁的对照地收集的土壤特性。采用植被点截距（VPI）取样方法沿横断面对植被物种进行取样，并通过三个植被覆盖度指标进行汇总：(1) 最高植被覆盖度；(2) 任何植被覆盖度；(3) 多重植被覆盖度。每个指标都是一个物种的总命中数除以样本点总数。VPI 任意命中覆盖度指标数据与 Landsat 图像相结合，绘制出高地苔原地区四种综合植物功能类型（PFTs）的任意命中覆盖度分数图；这四种植物功能类型是：苔藓植物、草本植物、地衣和灌木。植被横断面和土壤坑的照片作为配套文件提供。 这些数据描述了 Y-K 三角洲 Izaviknek 和 Kingaglia 高地在历史上发生大面积火灾后几十年的演替和景观变化。
共有 10 个主要数据集文件：2 个 *.csv 格式文件、4 个 GeoTIFF (*.tif) 格式文件、2 个 shapefiles (*.zip) 文件和 2 个 (*.kmz) 格式文件。还包括 244 个辅助文件：2 个 (*.csv) 格式的文件和 242 张联合摄影专家组 (*.jpg) 格式的地块照片。
将植被点截距（VPI）任意点覆盖度度量数据与大地遥感卫星图像相结合，绘制出阿拉斯加 Y-K 三角洲高地苔原地区四种植物功能类型（PFTs）的任意点覆盖度分数图，这四种植物功能类型分别为囊叶植物、草本植物、地衣和灌木。VPI 数据收集自 1971 年、1985 年、2005 年和 2015 年烧毁地区的地块。资料来源：Frost et al：Frost 等人，2020 年。
数据特征
空间覆盖范围：阿拉斯加州育空-库斯科克温三角洲（YKD）中部的 Izaviknek 和 Kingaglia 高地
上图参考地点：
域：核心 ABoVE
州/地区： 阿拉斯加州阿拉斯加州
以上网格单元： Ah000v000 ；
Bh001v003, Bh002v003, Bh002v004；
Ch014v019, Ch013v019, Ch011v020, Ch012v020, Ch013v020, Ch014v020、 Ch015v020, Ch011v021, Ch012v021, Ch013v021, Ch014v021, Ch015v021、 Ch012v022, Ch013v022, Ch014v022, Ch015v022, Ch016v022, Ch012v023、 Ch013v023, Ch014v023, Ch015v023, Ch016v023, Ch013v024, Ch014v024
空间分辨率：各种地块测量，植被覆盖图 30 平方米
时间覆盖范围：地块植被测量 2017-07-20 至 2018-07-16
时间分辨率：每年
研究区域：纬度和经度以十进制度表示。
Site | Westernmost Longitude | Easternmost Longitude | Northernmost Latitude | Southernmost Latitude |
|---|---|---|---|---|
Yukon-Kuskokwim Delta | -164.688 | -160.938 | 62.0883 | 60.3598 |
数据文件信息
该数据集包括 10 个文件：2 个逗号分隔值 (*.csv) 格式的文件、4 个 GeoTIFF (*.tif) 格式的文件、2 个 shapefiles (*.zip) 文件和 2 个 Keyhole Markup Language Zipped (*.kmz) 格式的文件。
File Name | Description |
|---|---|
vegetation_cover.csv | plot-level vegetation cover |
plot_details.csv | plot-level characterization data |
bryophyte_any_hit_cover.tif | Continuous cover map of bryophyte PFT, percentage of points where bryophyte species occurred combined with 60 spectral predictors derived from Landsat data. Included bryophyte species: acrocarpous mosses, liverworts, mosses, pleurocarpous mosses, and Sphagnum. |
lichen_any_hit_cover.tif | Continuous cover map of lichen PFT, percentage of points where lichen species occurred combined with 60 spectral predictors derived from Landsat data. |
herbaceous_any_hit_cover.tif | Continuous cover map of herbaceous PFT, percentage of points where herbaceous species occurred combined with 60 spectral predictors derived from Landsat data. Included herbaceous species: forbs, grasses, sedges, and rushes. |
shrub_any_hit_cover.tif | Continuous cover map of shrub PFT, percentage of points where shrub species occurred combined with 60 spectral predictors derived from Landsat data, including deciduous shrubs and evergreen shrubs. |
plot_centers.zip | locations of plots |
bounding_rectangle.zip | bounding rectangle around all plots |
plot_centers.kmz | locations of plots |
bounding_rectangle.kmz | bounding rectangle around all plots |
数据文件细节
对于 GeoTIFF 文件，数值是出现相应 PFT 的采样点的百分比，缺失值用 255 表示，每个文件包含 4,912 行和 4,583 列。
对于 CSV 文件，数字数据的缺失值用 -9999 表示，文本数据的缺失值用 NA 表示。
投影为 "Canada_Albers_Equal_Area_Conic"，EPSG：102001。
表 2.文件 vegetation_cover.csv 中的变量名和说明，也包括配套文件 vegetation_cover_data_dictionary.csv。
Variable Name | Description |
|---|---|
plot_id | Naming syntax: region_burn status-epoch-unique plot ID_sample year, where: region: YKDE = Yukon-Kuskokwim Delta burn status: B = burned, UB = unburned epoch (last burn): 1971, 1985, 2005, 2015 (only for plots with "B" burn status) unique plot ID = KX-X or XX (burned plots), XXXX (unburned plots), where X is a digit (e.g., “K4-01” or “0672” within a region and burn status) sample year: YYYY Examples: YKDE_B-2015-K3-01_2018 (burned), YKDE_UB-1026_2017 (unburned) |
date | date of data collection in YYYY-MM-DD format |
longitude | X coordinate of plot center in decimal degrees |
latitude | Y coordinate of plot center in decimal degrees |
species | vegetation taxon or ground cover type; vegetation nomenclature follows Viereck & Little (2010) for shrubs, Skinnner et al. (2012) for grasses, and Hulten (1969) for all other vascular taxa |
modifier | indicates standing dead (i.e., leaves and branches projecting above surface) or dead down (i.e., dead plant forms ground surface) status of vegetation; none = no modifier (i.e., live vegetation, detached litter, water, bare ground, etc.) |
plant_functional_type | categorical class for plant functional type; note that Equisetum spp. are treated as forbs in this classification |
any_hit_cover | the number of sample points where the species was intercepted ("hit") by a vertically mounted laser beam, divided by the total number of sample points (0-100%) |
multi_hit_cover | the number of times the species was intercepted ("hit") by a vertically mounted laser beam, divided by the total number of sample points (can exceed 100%) |
top_hit_cover | the number of sample points where the species was the first element intercepted ("hit") by a vertically mounted laser beam (i.e., formed the top of the canopy), divided by the total number of sample points (0-100%) |
表 3.plot_details.csv 文件中的变量名和说明，也包含在配套文件 plot_details_data_dictionary.csv 中。
Variable Name | Description |
|---|---|
plot_id | Naming syntax: region_burn status-epoch-unique plot ID_sample year, where: region: YKDE = Yukon-Kuskokwim Delta burn status: B = burned, UB = unburned epoch (last burn): 1971, 1985, 2005, 2015 (only for plots with "B" burn status) unique plot ID = KX-X or XX (burned plots), XXXX (unburned plots), where X is a digit (e.g., “K4-01” or “0672” within a region and burn status) sample year: YYYY Examples: YKDE_B-2015-K3-01_2018 (burned), YKDE_UB-1026_2017 (unburned) |
date | date of data collection in YYYY-MM-DD format |
longitude | X coordinate of plot center in decimal degrees |
latitude | Y coordinate of plot center in decimal degrees |
fire_year | year of last fire; burn status determined from AICC database and review of satellite imagery (Landsat and/or DigitalGlobe) |
years_since_fire | number of years elapsed between last fire and field sampling |
plot_radius | radius of plot in meters |
percent_burned | percent of plot area that actually burned; visually estimated from post-fire DigitalGlobe imagery (where available; 2015 burn scars only) |
mtbs_class | dominant fire severity class in Monitoring Trends in Burn Severity (MTBS) classification for burn (where available; burns after 2005 only; data gaps exist for some burns); see Eidinshink et al. 2007 |
slope | slope angle at plot center in degrees; measured using an inclinometer |
aspect | slope aspect at plot center in degrees; measured using a compass |
pH | soil pH; measured from free water in soil pit excavated near the center of each plot |
elec_cond | soil electrical conductivity in microsiemens; measured from free water in soil pit |
surf_org_thick | total thickness of surface organic material in soil profile in centimeters |
water_depth | water depth at the soil pit in centimeters; negative values indicate sub-surface |
LAI_mean | mean of leaf area index (LAI) measurements; measured at every fifth point along each transect using a LAI-2000 Plant Canopy Analyzer (LI-COR Biosciences, Lincoln NE, USA) |
LAI_stderr | standard error of mean LAI |
LAI_n | total number of LAI measurements at each plot; each measurement consisted of the mean of five LAI readings collected in an "X" pattern directly above each sample point and at four points 1 meter away |
woody_ht_mean | mean maximum shrub height in centimeters; measured within a 20 centimeter radius of every fifth point along each transect |
woody_ht_stddev | standard deviation of mean maximum shrub height in centimeters |
woody_ht_n | total number of maximum shrub height measurements at plot |
thaw_depth_mean | mean thaw depth in centimeters; measured at every fifth point along each transect |
thaw_depth_stddev | standard deviation of mean thaw depth in centimeters |
thaw_depth_n | total number of thaw depth measurements at plot |
veg_pt_intercept_n | total number of vegetation point-intercept sample points at plot |
veg_class_AVC | vegetation class for plot; adapted from Alaska Vegetation Classification (AVC), Level IV (Viereck et al. 1992) |
notes | field notes |
Companion Files
配套文件
该数据集包括 244 个配套文件：2 个逗号分隔值 (*.csv) 格式的文件和 242 个联合摄影专家组 (*.jpg) 格式的文件。
242 个 *.jpg 格式的文件是地块照片，其命名规则与表 2 第一行中描述的 plot_ID 相似。
植被横断面照片
命名语法：region_burn status-last burn epoch-plot ID_sample year_photo info.jpg，其中： 区域：YKDE = 育空-库斯科克温三角洲 燃烧状态：B = 已燃烧，UB = 未燃烧 年代（上次燃烧）：1971、1985、2005、2015（仅适用于燃烧状态为 "B "的地块） 地块 ID：KX-X 或 XX（已烧毁地块），XXXX（未烧毁地块），其中 X 为数字 样本年份：YYYY 照片信息：横断面线 = 1-3，照片方向 = C（从中心）或 E（横断面末端朝向中心）
例如YKDE_B-2005-02_2017_3E.JPG
土坑照片
命名语法：region_burn status-last burn epoch-plot ID_sample year_photo info.jpg，其中：
区域：YKDE = 育空-库斯科克温三角洲 燃烧状态：B = 已燃烧，UB = 未燃烧 年代（上次燃烧）：1971、1985、2005、2015（仅适用于燃烧状态为 "B "的地块） 地块 ID：KX-X 或 XX（已烧毁地块），XXXX（未烧毁地块），其中 X 为数字 样本年份：YYYY 照片信息： XXXX（唯一 ID）
例如：YKDE_B-1971-08_2017_0907.jpgYKDE_B-1971-08_2017_0907.JPG
表 4. 配套文件名称和说明
File Name | Description |
|---|---|
vegetation_cover_data_dictionary.csv | column names and descriptions for file vegetation_cover.csv |
plot_details_data_dictionary.csv | column names and descriptions for file plot_details.csv |
region_burn status-last burn epoch-plot ID_sample year_photo info.jpg | 242 plot vegetation transect and soil pit photos |
数据采集、材料和方法 阿拉斯加的育空-库斯科克维姆三角洲（YKD）是北极苔原生物群落中最温暖的地区之一，苔原火灾在其高地地区很常见。自 1953 年以来，约 20% 的育空地区（789 平方公里）经历过火灾，其中约一半的火灾发生在 2015 年（AICC，2019 年）。
以下是 Frost 等人（2020 年）提供的方法和分析的简要概述。
地块选择
采用分层随机方法在火灾梯度上选择小区位置，优先考虑 ABoVE 遥感飞行线内的点和 2015 年烧伤疤痕中的点（即火灾后 2-3 年采样）。
代码
!pip install leafmap
!pip install pandas
!pip install folium
!pip install matplotlib
!pip install mapclassify
import pandas as pd
import leafmap
url = "https://github.com/opengeos/NASA-Earth-Data/raw/main/nasa_earth_data.tsv"
df = pd.read_csv(url, sep="\t")
df
leafmap.nasa_data_login()
results, gdf = leafmap.nasa_data_search(
short_name="ABoVE_Izaviknek_Field_Data_1772",
cloud_hosted=True,
bounding_box=(-168.1, 49.54, -81.23, 75.0),
temporal=("2017-07-20", "2018-07-16"),
count=-1, # use -1 to return all datasets
return_gdf=True,
)
gdf.explore()
#leafmap.nasa_data_download(results[:5], out_dir="data")数据引用
Frost, G.V., R.A. Loehman, P.R. Nelson, and D.P. Paradis. 2020. ABoVE: Vegetation Composition across Fire History Gradients on the Y-K Delta, Alaska. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1772