Fig. 6: Structural equation modeling shows the direct and indirect effects of environmental (nutrients, salinity, and lake area) and meteorological factors on lake biodiversity and ecological network.

We hypothesized that environmental and meteorological indirectly affects ecological network characteristics by changes in biodiversity, that is, richness and turnover. Structural equation models for the succession stage 1 (a), stage 2 (b), and stage 3 (c) were constructed separately. The block represents the observed variable and the ellipse represents the latent variable. The orange and blue arrows indicate the negative and positive coefficients, respectively. And the dash arrows represent non-significant effects. The numbers on the arrows are the standardized coefficients, which represent the strength of the effect of one factor on another. The width of arrows is weighted according to standardized path coefficients.