One of the key issues in ecological systems is how populations distribute in both space and time. This can characterize the relationship between populations and evolution law. Hence, pattern dynamics in ecosystems has been widely studied including their causes and ecological functions. In an effort to systematically understand the interactions in ecosystems, the related results in pattern formation of ecological systems are summarized. Based on mathematical modeling and analysis, showed six mechanisms of pattern formation. This work discusses two of those mechanisms which include feedback and scale-dependent mechanisms. This review offers assistance for better understanding the complexity of ecosystems and provides new insights for self organizations, evolution and ecosystem protection.