( ( ( The ecology ) ( of communities ) ) ( ( is ( ( illustrated ( with lectures ) ) ( on ( ( ( ( ( ( ( primary production ) , ) ( energy flow ) ) , ) ( cycling ( of ( matter ( in ( ( ( ( ecosystems , ) ( species diversity ) ) and ) ( the succession ) ) ) ) ) ) ) and ) ( development ( of ( a community ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN ecology)) (PP (IN of) (NP (NNS communities)))) (VP (VBZ is) (VP (VBN illustrated) (PP (IN with) (NP (NNP lectures))) (PP (IN on) (NP (NP (NP (JJ primary) (NN production)) (, ,) (NP (NN energy) (NN flow))) (, ,) (NP (NP (NN cycling)) (PP (IN of) (NP (NP (NN matter)) (PP (IN in) (NP (NP (NNS ecosystems)) (, ,) (NP (NN species) (NN diversity)) (CC and) (NP (DT the) (NN succession))))))) (CC and) (NP (NP (NN development)) (PP (IN of) (NP (DT a) (NN community)))))))) (. .)))
The ecology of communities is illustrated with lectures on primary production, energy flow, cycling of matter in ecosystems, species diversity and the succession and development of a community.
(ROOT (S (NP (NP (DT A) (JJ primary) (NN role)) (PP (IN of) (NP (NP (NNS decomposers)) (PP (IN in) (NP (DT an) (NN ecosystem)))))) (VP (VBZ is) (SBAR (IN that) (S (NP (PRP they)) (VP (VBZ cycle) (NP (NN matter)) (PP (IN by) (S (VP (VBG returning) (NP (NN carbon) (CC and) (JJ other) (NN matter)) (PP (TO to) (NP (DT the) (NN ecosystem)))))))))) (. .)))
A primary role of decomposers in an ecosystem is that they cycle matter by returning carbon and other matter to the ecosystem.