( ( ( environmental ( ( factors and ) interactions ) ) ( among ( microbes ( as ( ( structuring forces ) ( in ( natural communities ) ) ) ) ) ) ) ; )
(ROOT (NP (NP (NP (JJ environmental) (NNS factors) (CC and) (NNS interactions)) (PP (IN among) (NP (NP (NNS microbes)) (PP (IN as) (S (VP (VBG structuring) (NP (NNS forces)) (PP (IN in) (NP (JJ natural) (NNS communities))))))))) (: ;)))
environmental factors and interactions among microbes as structuring forces in natural communities;
(ROOT (S (NP (NNP Community) (NNS interactions)) (VP (VBP are) (NP (NP (JJ important) (NNS factors)) (PP (IN in) (NP (JJ natural) (NN selection))))) (. .)))