( ( The ( research team ) ) ( ( is ( attempting ( to ( quantify ( ( the role ) ( of ( ( the ( steppe ecosystem ) ) ( in ( the ( global ( carbon cycle ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN research) (NN team)) (VP (VBZ is) (VP (VBG attempting) (S (VP (TO to) (VP (VB quantify) (NP (NP (DT the) (NN role)) (PP (IN of) (NP (NP (DT the) (JJ steppe) (NN ecosystem)) (PP (IN in) (NP (DT the) (JJ global) (NN carbon) (NN cycle))))))))))) (. .)))
The research team is attempting to quantify the role of the steppe ecosystem in the global carbon cycle.
(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.