In this paper, the phenomenon that the variation in nutrient and water temperature could cause changes in phytoplankton growth and structure is examined; and the question of how a marine ecosystem make up the earth ecosystem step by step to auto-sustain the balance between phytoplankton and nutrient supply especially Si is discussed. Three major complementary mechanisms of the earth ecosystem for nutrient Si, water temperature and carbon were put forward. Understanding the mechanisms nowadays would explain the why the El Ni(n)o and La Ni(n)a occurred, and forecast the trend of human-impacted the earth, which would alert us with proactive countermeasures.