Relationship between species body mass and abundance (dark blue), individual mass distribution (light blue) and species-richness mass distribution (orange) in communities across one-degree cells as a function of global gradients of net primary productivit (IMAGE)
Caption
Relationship between species body mass and abundance (dark blue), individual mass distribution (light blue) and species-richness mass distribution (orange) in communities across one-degree cells as a function of global gradients of net primary productivity (NPP) (A, C) and human footprint (B, C). MAR-SPP, IMD and RMD slopes represent the exponent in power law relationships. Panel A shows the NPP effect on MAR-SPP, IMD and RMD values adjusted for human footprint and panel B shows the human-footprint effect adjusted for NPP. In A and B, the graph uses a boxplot format where the white central section represents the interquartile range between 25% and 75%, the central line denotes the median and the shaded areas indicate the whiskers. Outliers are omitted for clarity. The dashed line depicts a reference of slope = -0.75. Boxplots were calculated in intervals of 0.001 for NPP and every unit of human footprint raised to the 1/4 power. Lines were smoothed with a loess regression with a 0.06 span (α). The boxplots were drawn from the mean value per one-degree cell across 10 global datasets. In A and B, thicker lines represent the mean slopes of 10,000 general linear model (GLM) iterations (1000 iterations on 10 data sets), based on random samples of 20 one-degree cells. In C, GLM slopes are shown across the combined effects of NPP and human footprint. GLM slopes (thick lines in A and B and coloured areas in C) appear to depict non-linear relationships because of back-transformation of NPP and human footprint, which were squared-root and fourth-root transformed for GLM.
Credit
Camacho & Araújo, 2026
Usage Restrictions
Credit must be given to the creator.
License
CC BY