Is the seeds' dormancy adaptable for changing environment? Let me assume that there are two kind of years, one is suitable for a plant and another is not. The freqency of comfortable year is p and another is (1-p). You can set the parameter of survival rate of dormant seeds (s). Also you can set the number of seed per one grown plant. This value of comfotable year should be different from that of bad conditioned year. In this simulation, you can find that the plant of germination rate (x) near the value p inceleases (only if you choose large Yg value.