(4)
where HQIxj is the habitat quality of the grid x for the land use type j,Hj represents the habitat suitability of land use type j ,Dxj refers to the habitat stress level of the grid x for the land use type j. irxy refers to the stress role of the factor rof gridyon the gridx, dxy refers to a straight line between grid x and grid y. drmax represents the maximum effect distance of the stress factorr.wris the weight
of stress factor, which represents the relative damage of a stress factor on all habitats .bx represents the level of accessibility grid x .Sjr represents the sensitivity of the stress factor r on the land
use type j. k is the constant of half-saturation. When the formula