How can I see which parameter is the one I want to alter?

Hey people,

I'm currently running a model with two state variables:

A(1:10)'=rA.*A.*(K-a*A)./K-A.*(H*(cons./(F+1E-10)))+u;
Z(1:6)'=e.*cons-m.*Z;

with:
F=H'*A;
cons=g.*Z.*F./(F+hZ);

and
A=10*rand(10,1);
Z=10*rand(6,1);
K=10;
a=rand(10)+0.5;
a(logical(eye(length(a))))=1;
m=0.15;
e=0.6;
rA=0.5;
g=0.4;
hZ=0.6;
u=0.001;
H=[   1     1     1     1     1     1
        0     1     1     1     1     1
        0     0     1     1     1     1
        0     0     0     1     1     1
        0     0     0     0     1     1
        0     0     0     0     1     1
        0     0     0     0     0     1
        0     0     0     0     0     1
        0     0     0     0     0     1
        0     0     0     0     0     1];

It's a multispecies competition model.

However, everytime I run the model, I find the zooplankton species (A(1:6)) to be very low.

I can't find out which parameter is the one I should adjust in order to not let this happen.

Does anyone know a kind of analysis to see which parameter is doing what? to the state vars?

Thanks in forward