Table 3. Global Sensitivity Analysis^a.

	FOi				TOi
	δ13C	X	Sbio	S	δ13C	X	Sbio	S
Sin	0.0014	0	0.0152	0.0377	0	0.01119	0.0049	0.0165
μmax	0.2706	0	0.4153	0.2663	0.2658	0.2217	0.4108	0.2559
Km	0.4010	0	0.5737	0.3584	0.4052	0.3194	0.5914	0.3690
ktr	0.3294	0	0.0114	0.5780	0.3276	0.1208	0	0.5531

^aThe first-order index (FO_i) and the total-order index (TO_i) of the output parameters (δ¹³C-values, X, S_bio, and S) in respect to the input parameters (S_in, μ_max, K_m, and k_tr). The higher the value, the more impact the input variability exerts on the variance of the output parameter. Note that both heavy and light isotopologues showed a similar sensitivity trend in bulk and bioavailable domains.