## 2.23.1. Mortality Fluxes Leaving Vegetation Pools[¶](#mortality-fluxes-leaving-vegetation-pools "Permalink to this headline")
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Whole-plant mortality is parameterized very simply, assuming a mortality rate of 2% yr\-1 for all vegetation types. This is clearly a gross oversimplification of an important process, and additional work is required to better constrain this process in different climate zones ([Keller et al. 2004](https://escomp.github.io/ctsm-docs/versions/master/html/tech_note/References/CLM50_Tech_Note_References.html#kelleretal2004); [Sollins 1982](https://escomp.github.io/ctsm-docs/versions/master/html/tech_note/References/CLM50_Tech_Note_References.html#sollins1982)), for different species mixtures ([Gomes et al. 2003](https://escomp.github.io/ctsm-docs/versions/master/html/tech_note/References/CLM50_Tech_Note_References.html#gomesetal2003)), and for different size and age classes ([Busing 2005](https://escomp.github.io/ctsm-docs/versions/master/html/tech_note/References/CLM50_Tech_Note_References.html#busing2005); [Law et al. 2003](https://escomp.github.io/ctsm-docs/versions/master/html/tech_note/References/CLM50_Tech_Note_References.html#lawetal2003)). Literature values for forest mortality rates range from at least 0.7% to 3.0% yr\-1. Taking the annual rate of mortality (_am_, proportion yr\-1) as 0.02, a mortality rate per second (_m_) is calculated as \\(m={am\\mathord{\\left/ {\\vphantom {am \\left(365\\cdot 86400\\right)}} \\right.} \\left(365\\cdot 86400\\right)}\\). All vegetation carbon and nitrogen pools for display, storage, and transfer are affected at rate _m_, with mortality fluxes out of vegetation pools eventually merged to the column level and deposited in litter pools. Mortality (_mort_) fluxes out of displayed vegetation carbon and nitrogen pools are

(2.23.1)[¶](#equation-33-1 "Permalink to this equation")\\\[CF\_{leaf\\\_ mort} =CS\_{leaf} m\\\]

(2.23.2)[¶](#equation-33-2 "Permalink to this equation")\\\[CF\_{froot\\\_ mort} =CS\_{froot} m\\\]

(2.23.3)[¶](#equation-33-3 "Permalink to this equation")\\\[CF\_{livestem\\\_ mort} =CS\_{livestem} m\\\]

(2.23.4)[¶](#equation-33-4 "Permalink to this equation")\\\[CF\_{deadstem\\\_ mort} =CS\_{deadstem} m\\\]

(2.23.5)[¶](#equation-33-5 "Permalink to this equation")\\\[CF\_{livecroot\\\_ mort} =CS\_{livecroot} m\\\]

(2.23.6)[¶](#equation-33-6 "Permalink to this equation")\\\[CF\_{deadcroot\\\_ mort} =CS\_{deadcroot} m\\\]

(2.23.7)[¶](#equation-33-7 "Permalink to this equation")\\\[NF\_{leaf\\\_ mort} =NS\_{leaf} m\\\]

(2.23.8)[¶](#equation-33-8 "Permalink to this equation")\\\[NF\_{froot\\\_ mort} =NS\_{froot} m\\\]

(2.23.9)[¶](#equation-33-9 "Permalink to this equation")\\\[NF\_{livestem\\\_ mort} =NS\_{livestem} m\\\]

(2.23.10)[¶](#equation-33-10 "Permalink to this equation")\\\[NF\_{deadstem\\\_ mort} =NS\_{deadstem} m\\\]

(2.23.11)[¶](#equation-33-11 "Permalink to this equation")\\\[NF\_{livecroot\\\_ mort} =NS\_{livecroot} m\\\]

(2.23.12)[¶](#equation-33-12 "Permalink to this equation")\\\[NF\_{deadcroot\\\_ mort} =NS\_{deadcroot} m\\\]

(2.23.13)[¶](#equation-33-13 "Permalink to this equation")\\\[NF\_{retrans\\\_ mort} =NS\_{retrans} m.\\\]

where CF are carbon fluxes, CS is carbon storage, NF are nitrogen fluxes, NS is nitrogen storage, _croot_ refers to coarse roots, _froot_ refers to fine roots, and _retrans_ refers to retranslocated.

Mortality fluxes out of carbon and nitrogen storage (_stor)_ pools are

(2.23.14)[¶](#equation-33-14 "Permalink to this equation")\\\[CF\_{leaf\\\_ stor\\\_ mort} =CS\_{leaf\\\_ stor} m\\\]

(2.23.15)[¶](#equation-33-15 "Permalink to this equation")\\\[CF\_{froot\\\_ stor\\\_ mort} =CS\_{froot\\\_ stor} m\\\]

(2.23.16)[¶](#equation-33-16 "Permalink to this equation")\\\[CF\_{livestem\\\_ stor\\\_ mort} =CS\_{livestem\\\_ stor} m\\\]

(2.23.17)[¶](#equation-33-17 "Permalink to this equation")\\\[CF\_{deadstem\\\_ stor\\\_ mort} =CS\_{deadstem\\\_ stor} m\\\]

(2.23.18)[¶](#equation-33-18 "Permalink to this equation")\\\[CF\_{livecroot\\\_ stor\\\_ mort} =CS\_{livecroot\\\_ stor} m\\\]

(2.23.19)[¶](#equation-33-19 "Permalink to this equation")\\\[CF\_{deadcroot\\\_ stor\\\_ mort} =CS\_{deadcroot\\\_ stor} m\\\]

(2.23.20)[¶](#equation-33-20 "Permalink to this equation")\\\[CF\_{gresp\\\_ stor\\\_ mort} =CS\_{gresp\\\_ stor} m\\\]

(2.23.21)[¶](#equation-33-21 "Permalink to this equation")\\\[NF\_{leaf\\\_ stor\\\_ mort} =NS\_{leaf\\\_ stor} m\\\]

(2.23.22)[¶](#equation-33-22 "Permalink to this equation")\\\[NF\_{froot\\\_ stor\\\_ mort} =NS\_{froot\\\_ stor} m\\\]

(2.23.23)[¶](#equation-33-23 "Permalink to this equation")\\\[NF\_{livestem\\\_ stor\\\_ mort} =NS\_{livestem\\\_ stor} m\\\]

(2.23.24)[¶](#equation-33-24 "Permalink to this equation")\\\[NF\_{deadstem\\\_ stor\\\_ mort} =NS\_{deadstem\\\_ stor} m\\\]

(2.23.25)[¶](#equation-33-25 "Permalink to this equation")\\\[NF\_{livecroot\\\_ stor\\\_ mort} =NS\_{livecroot\\\_ stor} m\\\]

(2.23.26)[¶](#equation-33-26 "Permalink to this equation")\\\[NF\_{deadcroot\\\_ stor\\\_ mort} =NS\_{deadcroot\\\_ stor} m\\\]

where _gresp_ refers to growth respiration.

Mortality fluxes out of carbon and nitrogen transfer (_xfer)_ growth pools are

(2.23.27)[¶](#equation-33-27 "Permalink to this equation")\\\[CF\_{leaf\\\_ xfer\\\_ mort} =CS\_{leaf\\\_ xfer} m\\\]

(2.23.28)[¶](#equation-33-28 "Permalink to this equation")\\\[CF\_{froot\\\_ xfer\\\_ mort} =CS\_{froot\\\_ xfer} m\\\]

(2.23.29)[¶](#equation-33-29 "Permalink to this equation")\\\[CF\_{livestem\\\_ xfer\\\_ mort} =CS\_{livestem\\\_ xfer} m\\\]

(2.23.30)[¶](#equation-33-30 "Permalink to this equation")\\\[CF\_{deadstem\\\_ xfer\\\_ mort} =CS\_{deadstem\\\_ xfer} m\\\]

(2.23.31)[¶](#equation-33-31 "Permalink to this equation")\\\[CF\_{livecroot\\\_ xfer\\\_ mort} =CS\_{livecroot\\\_ xfer} m\\\]

(2.23.32)[¶](#equation-33-32 "Permalink to this equation")\\\[CF\_{deadcroot\\\_ xfer\\\_ mort} =CS\_{deadcroot\\\_ xfer} m\\\]

(2.23.33)[¶](#equation-33-33 "Permalink to this equation")\\\[CF\_{gresp\\\_ xfer\\\_ mort} =CS\_{gresp\\\_ xfer} m\\\]

(2.23.34)[¶](#equation-33-34 "Permalink to this equation")\\\[NF\_{leaf\\\_ xfer\\\_ mort} =NS\_{leaf\\\_ xfer} m\\\]

(2.23.35)[¶](#equation-33-35 "Permalink to this equation")\\\[NF\_{froot\\\_ xfer\\\_ mort} =NS\_{froot\\\_ xfer} m\\\]

(2.23.36)[¶](#equation-33-36 "Permalink to this equation")\\\[NF\_{livestem\\\_ xfer\\\_ mort} =NS\_{livestem\\\_ xfer} m\\\]

(2.23.37)[¶](#equation-33-37 "Permalink to this equation")\\\[NF\_{deadstem\\\_ xfer\\\_ mort} =NS\_{deadstem\\\_ xfer} m\\\]

(2.23.38)[¶](#equation-33-38 "Permalink to this equation")\\\[NF\_{livecroot\\\_ xfer\\\_ mort} =NS\_{livecroot\\\_ xfer} m\\\]

(2.23.39)[¶](#equation-33-39 "Permalink to this equation")\\\[NF\_{deadcroot\\\_ xfer\\\_ mort} =NS\_{deadcroot\\\_ xfer} m\\\]

