Code and Data: Power laws and critical fragmentation in global forests

Source code for image processing and statistical analysis, and the patch size data files for the manuscript: Power laws and critical fragmentation in global forests. (2016) Saravia L.A. Doyle S.R. Bond-Lamberty B. bioRxiv 091751; doi: http://dx.doi.org/10.1101/091751 Zip Files: Patch Sizes distribution by region, year and threshold from 2000 to 2015: these are binary files consisting on a vector of doubles, the R command used to read it is readBin(connection_file, "double", n = 10^8) Africa_PatchSizes.zipNorthamerica_PatchSizes.zipSouthamerica_PatchSizes.zipEurasia_PatchSizes.zipOceania_PatchSizes.zipSouthasia_PatchSizes.zip LargestPatchAnimations.zip Animations of the two largest patches for all the regions defined in the paper. PercolationAnimations.zip Animation demonstrating percolation in a forest/non-forest model Study_areas_definition.zip These files needed to be unziped in a folder and the location added to the script data_input_script.m file R markdown files: Threshold_sensitivity.Rmd # Fitting heavy tails to modis VCF, Smax & RSmax patch analysis. Download_modis.Rmd # Download modis files MOD44B version 051 Map_study_areas.Rmd # Generate maps of study areas Map_Max_patches.Rmd # Generate GIF animations of maximum patch dynamics R Files map_fun.r # Map raster functionspower_fun.r # Function to fit continuos heavy tail distributions MATLAB Files Extract patch sizes from bin, and other analysis not used in the paper data_input_script.mGCF_spatial_analyses.m PYTHON Files powlawfit.py : Call the Python powerlawpackage from command line DATA Tables: csv and tab separated text files with model fits for the patch size distribution models. Fitted_Patch_models.csvFitted_Patch_models.txt

本数据集包含用于图像处理与统计分析的源代码，以及对应学术论文《全球森林中的幂律与临界破碎》（Power laws and critical fragmentation in global forests, 2016, Saravia L.A., Doyle S.R., Bond-Lamberty B.）的斑块尺寸数据文件，该预印本发布于bioRxiv 091751，DOI：http://dx.doi.org/10.1101/091751。

### 压缩包文件
1. 按区域、年份及阈值划分的2000年至2015年斑块尺寸分布数据压缩包：文件为双精度向量格式的二进制文件，读取所用R命令为`readBin(connection_file, "double", n = 10^8)`，对应压缩包包括：Africa_PatchSizes.zip、Northamerica_PatchSizes.zip、Southamerica_PatchSizes.zip、Eurasia_PatchSizes.zip、Oceania_PatchSizes.zip、Southasia_PatchSizes.zip。
2. LargestPatchAnimations.zip：包含论文中定义的所有区域的两大斑块动态动画文件。
3. PercolationAnimations.zip：演示森林/非森林模型中渗流现象的动画文件。
4. Study_areas_definition.zip：需将该压缩包解压至指定文件夹，并将该文件夹路径添加至脚本`data_input_script.m`中。

### R Markdown脚本
- `Threshold_sensitivity.Rmd`：用于对MODIS VCF（MODIS植被连续场）数据拟合重尾分布、开展Smax与RSmax斑块分析的脚本。
- `Download_modis.Rmd`：用于下载MODIS文件（MOD44B 版本051）的脚本。
- `Map_study_areas.Rmd`：用于生成研究区域地图的脚本。
- `Map_Max_patches.Rmd`：用于生成最大斑块动态GIF动画的脚本。

### R脚本文件
- `map_fun.r`：栅格绘图函数脚本。
- `power_fun.r`：用于拟合连续型重尾分布的函数脚本。

### MATLAB脚本文件
包含从二进制文件提取斑块尺寸以及论文未采用的其他分析的脚本，包括`data_input_script.m`与`GCF_spatial_analyses.m`。

### Python脚本文件
`powlawfit.py`：用于通过命令行调用Python powerlaw包的脚本。

### 数据集表格
包含斑块尺寸分布模型拟合结果的CSV文件与制表符分隔文本文件，包括`Fitted_Patch_models.csv`与`Fitted_Patch_models.txt`。