Homework SourseThe figure below from Law et al 2001 shows a carbon budget f
The figure below (from Law et al., 2001) shows a carbon budget for old and young ponderosa pine forests. The numbers in each component show g C/m^2 in each pool (see the table below for pool identification). The only fluxes shown are net primary production (NPP) and respiration by heterotrophic (feeding on other things; not making their own food) organisms (R_h). a) Using the figure, compare old and young ponderosa pine forests in terms of their C pools. b) Compare old and young ponderosa pine forests in terms of the C fluxes due to NPP and R_h. c) For each of the two forests types (old and young), state whether or not it\'s a C source or sink, based upon the information you have here. Give the evidence you used for your answer. d) Explain the importance of what you wrote in part c) above, given the current climate change issues stemming from increasing atmospheric CO_2 concentrations.
Solution
As we see from both tables that carbon releasing capacity of old forest is high and it act as a source pool for carbon.
However young forest act as a sink of fixing CO2 from atmosphere.
B.
If we talk about old forest it\'s NPP is 472 and Rs is 444 i.e. these forest act as a negative flux and release CO2 in atmosphere. Whereas new pine forests NPP is 357 & Rs 387 i.e. this forest act as a positive flux and sink carbo concentration from atmosphere into wood form.
| Foliage | 60 |
| Wood | 519 |
| Roots | 563 |
| Soil | 4310 |
| Detritus | 2535 |
| Litter | 708 |
| Above ground understory | 322 |
