Table 1.

Synthesis of C-STABILITY parameters and scenarios setups with values for initial conditions, microbes traits, and enzymes families. Scenario 1 corresponds to cellulose degradation, scenario 2 to lignocellulose degradation, scenario 3 to succession of two different microbial communities on lignocellulose, considering microbial recycling, and scenario 4 to soil organic matter at steady state considering a continuous plant input and microbial recycling, with only one microbial community. Initial amounts of microbes and substrate are respectively noted ${\left(C_{\mathrm{mic}}\right)}_{t=0}$ and ${\left(C_{\mathrm{sub}}\right)}_{t=0}$, mic. stands for microbe and sub. for substrate. For scenario 3, two $u_{\mathrm{mic}}^0$ values were tested to compare non-cheating and cheating behavior of decomposers. For scenario 4, the values of ${\tau }_{\mathrm{enz}}^0$ were divided by 5 to account for in situ conditions, while other scenarios are based on laboratory case studies (Supplementary Table 1).

Parameter	Description							Unit
$u_{\mathrm{mic}}^0$	Microbial uptake rate per microbial carbon mass							g${}_C^{-1}$.d−1
$e_{\mathrm{mic}}^0$	Microbial carbon use efficiency							−
$m_{\mathrm{mic}}^0$	Microbial mortality rate							g${}_C^{-1}$.d−1
${\tau }_{\mathrm{enz}}^0$	Enzymatic action rate per microbial carbon mass							g${}_C^{-1}$.d−1
αenz	Enzymatic substrate cleavage factor							−

Initial setup for each scenario
Scenario	Microbes	Initial conditions (gC)		Microbial signature			Plant biochemistry
		${\left(C_{\mathrm{mic}}\right)}_{t=0}$	${\left(C_{\mathrm{sub}}\right)}_{t=0}$	Lipid	Protein	Mic. sugar	Plant sugar	Lignin
1	Plant decomposer	5	95	–	–	–	100%	–
2	Plant decomposer	5	125	–	–	–	76%	24%
3	Plant/mic. decomposer	5/5	125	30%	20%	50%	76%	24%
4	General decomposer	–	–	30%	20%	50%	76%	24%

Microbes parameters for each scenario
Scenario	Microbes	$e_{\mathrm{mic}}^0$	$m_{\mathrm{mic}}^0$	$u_{\mathrm{mic}}^0$
				Lipid	Protein	Mic. sugar	Plant sugar	Lignin
1	Plant decomposer	0.4	0.02	−	−	−	5	−
2	Plant decomposer	0.4	0.02	−	−	−	5	5
3	Plant decomposer	0.4	0.02	0/3	0/3	0/3	5	5
3	Mic. decomposer	0.5	0.01	5	5	5	0/3	0/3
4	General decomposer	0.4	0.02	5	5	5	5	5

Enzymes parameters for each scenario
Scenario	Enzymes action						${\tau }_{\mathrm{enz}}^0$	αenz
1-2-3/4	Cellulolysis						1.8/0.36	5
2-3/4	Lignolysis						1/0.2	7
3/4	Lipidolysis						0.8/0.16	1.5
3/4	Proteolysis						1.8/0.36	5.5
3/4	Microbial sugar lysis						1.8/0.36	5