Examining local and regional ecological connectivity throughout North America

Output from 12 Omniscape model runs using three resistance surfaces and four moving window sizes (Belote et al. 2022, Landscape Ecology). Resistance surfaces were created through alternative transformations (varying c) of the 2015 estimates of human modification from Theobald et al. (2020). The radius of the circular moving windows were 30-km, 150-km, 300-km, or 700-km. Descriptions of directories are in the csv file called “folder descriptions.” There are three outputs within each of the 12 folders: cum_currmap, flow_potential, and normalized_cum_currmap. These are, respectively: 1. Cumulative current flow: the total current flowing through the landscape – the result of the Omniscape algorithm described above.<br> 2. Flow potential (optional): current flow under "null" resistance conditions. Flow potential demonstrates what movement/flow would look like when movement is unconstrained by resistance and barriers. Flow potential is calculated exactly as cumulative current flow is, but with resistance set to 1 for the entire landscape.<br> 3. Normalized current flow (optional): calculated as cumulative current flow divided by flow potential. Normalized current helps identify areas where current is impeded or channelized (e.g. more or less current than expected under null resistance conditions). High values mean current flow is channelized, low values mean current is impeded. Descriptions of outputs above are quoted directly from https://docs.juliahub.com/Omniscape/uqaJf/0.4.3/. <br> References: Belote, RT, Barnett K, Zeller K, Brennan A, and Gage J (2022) Examining local and regional ecological connectivity throughout North America. Landscape Ecology Theobald DM, Kennedy C, Chen B, et al (2020) Earth transformed: Detailed mapping of global human modification from 1990 to 2017. Earth System Science Data 12:1953–1972. https://doi.org/10.5194/essd-12-1953-2020本数据集为12次Omniscape模型运行的输出结果，实验采用3种阻力面（resistance surface）与4种移动窗口尺寸（moving window size），相关实验设计参见Belote等2022年发表于《景观生态学（Landscape Ecology）》的研究。 阻力面基于Theobald等人（2020）发布的2015年全球人类活动改造程度估算数据，通过调整参数c的差异化变换方式生成。本次实验设置的圆形移动窗口半径分别为30千米、150千米、300千米与700千米。各目录的详细说明收录于名为"folder descriptions"的CSV文件中。 12个文件夹中的每个均包含3类输出文件：cum_currmap、flow_potential与normalized_cum_currmap，分别对应： 1. 累积电流流（cum_currmap）：景观中流动的总电流通量，即前述Omniscape算法的运算结果。 2. 流动势（flow_potential，可选输出）：“零阻力”条件下的电流流。流动势可展示当移动不受阻力与障碍约束时的运动/流态分布，其计算逻辑与累积电流流完全一致，但将全景观的阻力值统一设为1。 3. 归一化累积电流流（normalized_cum_currmap，可选输出）：以累积电流流除以流动势得到。该指标可用于识别电流流受阻或集中的区域，即相较于零阻力条件下的预期值，电流流偏多或偏少的区域。其中高值代表电流流被集中疏导，低值代表电流流受到阻碍。 上述输出的详细说明直接引自https://docs.juliahub.com/Omniscape/uqaJf/0.4.3/。 参考文献： Belote RT, Barnett K, Zeller K, Brennan A, Gage J. 2022. 探究北美全域的局地与区域生态连通性. 《景观生态学（Landscape Ecology）》 Theobald DM, Kennedy C, Chen B, 等. 2020. 地球重塑：1990-2017年全球人类活动改造程度的精细化制图. 《地球系统科学数据（Earth System Science Data）》12:1953–1972. https://doi.org/10.5194/essd-12-1953-2020