next up previous
Next: The ``naked'' planet Up: Parametrization Previous: The behaviour of as

Equilibrium tex2html_wrap_inline1575 as a function of tex2html_wrap_inline1577 and A

The equilibrium tex2html_wrap_inline1575 of the system is determined by the solution of eq. (14). For tex2html_wrap_inline1583 we have
 eqnarray419
where tex2html_wrap_inline1585. It is obvious that tex2html_wrap_inline1509. Since N>0 then
 equation433
i.e. tex2html_wrap_inline1575 only within the interval tex2html_wrap_inline1593, where tex2html_wrap_inline1595.

It is interesting that the interval is reduced to a point, i.e. tex2html_wrap_inline1597, if tex2html_wrap_inline1599, where tex2html_wrap_inline1601 is defined as
equation442
It is obvious that, if tex2html_wrap_inline1603, tex2html_wrap_inline1575 does not exist, and there are the solutions tex2html_wrap_inline1485 and tex2html_wrap_inline1609 alone. In Fig. 8 the different N(T), corresponding to different values of A, are shown. The maximum of N in respect to T is tex2html_wrap_inline1619. It is obvious that tex2html_wrap_inline1621 and it reaches that point at tex2html_wrap_inline1623.

  figure457
Figure 8: The carbon mass in vegetation in equilibrium N as a function of the equilibrium temperature T and the total amount of carbon A in the system. For tex2html_wrap_inline1603 equilibrium with N=0 exist alone.

Let us remember the stability condition for the equilibrium tex2html_wrap_inline1635 (see formulas (19)-(20)). Since tex2html_wrap_inline1637, then from (19) it follows:
equation471
i.e. this equilibrium is stable, and if
equation475
it is unstable.

Let us compare these expressions to (36). Hence, this equilibrium is always unstable, if tex2html_wrap_inline1639, and it is stable if tex2html_wrap_inline1641. It is obvious that for tex2html_wrap_inline1643 the unique equilibrium tex2html_wrap_inline1645 exists and is stable.


next up previous
Next: The ``naked'' planet Up: Parametrization Previous: The behaviour of as

Werner von Bloh (Data & Computation)
Thu Jul 13 11:24:58 MEST 2000