fixes the conflation of soil and microbial maintenance respiration by splitting it

src/sipnet/sipnet.c

@@ -1098,11 +1098,11 @@ void calcSoilMaintRespiration(double tsoil, double water, double whc) {
     double tillageEffect = 1 + eventTrackers.d_till_mod;
 
     // Put it all together!
-    fluxes.maintRespiration = envi.soil * params.baseSoilResp * moistEffect *
-                              tempEffect * tillageEffect;
+    fluxes.soilMaintRespiration = envi.soil * params.baseSoilResp *
+                                  moistEffect * tempEffect * tillageEffect;
 
     // With no microbes, rSoil flux is just the maintenance respiration
-    fluxes.rSoil = fluxes.maintRespiration;
+    fluxes.rSoil = fluxes.soilMaintRespiration;
   }
   // else fluxes.rSoil = 0.0?
 }
@@ -1137,12 +1137,14 @@ void calcMicrobeFluxes(double tsoil, double water, double whc,
     // respiration is determined by microbe biomass
     // :: from [4], eq (5.12) with addition of moisture effect
     // [TAG:UNKNOWN_PROVENANCE]  moistEffect
-    tempEffect = params.baseMicrobeResp * pow(params.microbeQ10, tsoil / 10);
-    fluxes.maintRespiration = envi.microbeC * moistEffect * tempEffect;
+    tempEffect = pow(params.microbeQ10, tsoil / 10);
+    fluxes.microbeMaintRespiration =
+        envi.microbeC * params.baseMicrobeResp * moistEffect * tempEffect;
 
   } else {
     fluxes.microbeIngestion = 0.0;
     fluxes.soilPulse = 0.0;
+    fluxes.microbeMaintRespiration = 0.0;
     // fluxes.maintRespiration is otherwise set, do not set to zero here
   }
 }
@@ -1566,13 +1568,13 @@ void updatePoolsForSoil(void) {
     // ::      eq (5.11) used for soilPulse, and
     // ::      eq (5.12) used for maintRespiration
     envi.microbeC += (microbeEff * fluxes.microbeIngestion + fluxes.soilPulse -
-                      fluxes.maintRespiration) *
+                      fluxes.microbeMaintRespiration) *
                      climate->length;
 
     // rSoil is maintenance resp + growth (microbe) resp
     // :: from [4], eq (5.10) for microbe term
-    fluxes.rSoil =
-        fluxes.maintRespiration + (1 - microbeEff) * fluxes.microbeIngestion;
+    fluxes.rSoil = fluxes.microbeMaintRespiration +
+                   (1 - microbeEff) * fluxes.microbeIngestion;
   } else {
     if (ctx.litterPool) {
       // :: from [2], litter model description

src/sipnet/state.h

@@ -516,11 +516,12 @@ typedef struct FluxVars {
   // microbes on: microbial maintenance respiration rate
   // microbes off: equivalent to rSoil, calc'd as described in [1], eq (A20)
   // (g C m-2 ground area day^-1)
-  double maintRespiration;
+  double microbeMaintRespiration;
   // Flux that microbes remove from soil (mg C g soil day)
   // TBD I highly doubt those units; this is calc'd as
   //     (g C * m-2) * (day-1) * (unitless terms)
   double microbeIngestion;
+  double soilMaintRespiration;
   // Exudates into the soil
   double soilPulse;