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A Stieltjes renewal equation at the metapopulation level.

In order to arrive at a Stieltjes renewal equation we will follow the lines set out in Diekmann & Metz ([1]). On the patch level the ingredients are again local population growth, disasters and survival up to the next disaster. We consider the following quantities:

tex2html_wrap_inline2020 Local population size at time t in a patch, which had a local population size tex2html_wrap_inline2024 at tex2html_wrap_inline2026 , and experienced a disperser density tex2html_wrap_inline2028 on the interval tex2html_wrap_inline2030 . Note that this quantity is a solution of Eq. (2) provided with the proper initial conditions.

tex2html_wrap_inline2032 The probability that a patch, which had a local population size tex2html_wrap_inline2024 at tex2html_wrap_inline2026 , has not been hit by a disaster at time t.

  eqnarray123

= The probability that in the time interval tex2html_wrap_inline2030 a patch is hit by a disaster, and after the disaster the patch is suitable for habitation and has tex2html_wrap_inline2042 survivors.

  equation136

= The probability that in the time interval tex2html_wrap_inline2030 a patch is hit by a disaster, and that after the disaster the patch has become unsuitable for habitation.

On the metapopulation level we gather the dynamics of the local populations in the cumulative operator tex2html_wrap_inline2046 for patch restart (i.e. the birth operator in [1]), which is defined by

  eqnarray145

Mass conservation (1) can be rewritten in terms of the birth operator as

  equation151

Likewise the change in disperser density (11) can be rewritten as

  equation157

And so our problem is fully posed in terms of the birth operator B and the disperser density D.



John Val
Wed Feb 26 07:30:07 EST 1997