Ecosystem reliability and its stability maintenance

Trophic structure of ecosystems is composed of several trophic levels.According to reliability model,the reliability of trophic level is depended on species failure rate,and there are little effects on the reliability of trophic levels with abundant species and high failure rate by species losing,but obvious effects on the trophic level with few species and low failure rate.In another word,there is no closely relationship between the reliability of trophic levels and species richness.In addition,if the reliability of trophic levels is same,simple ecosystems have higher reliability than complicated ecosystems with more trophic levels or longer food chains.So,there is no certain relationship between biodiversity and ecosystem stability.If trophic levels remained(no matter how many species left),ecosystems structured by series and parallel connection would not collapse.Ecosystem stability is a kind of the stability of redundancy structure.If ecosystems were frequently disturbed,species and individual loss would make up by inside and outside redundancy recruitment to maintain the stability of ecosystem trophic structure.