( ( ( ( MATTER AND ) ENERGY ) ( IN ( ECOSYSTEMS ( Understand ( ( populations and ) communities ) ) ) ) ) . )
(ROOT (NP (NP (NNP MATTER) (CC AND) (NNP ENERGY)) (PP (IN IN) (NP (NNP ECOSYSTEMS) (NNP Understand) (NNS populations) (CC and) (NNS communities))) (. .)))
MATTER AND ENERGY IN ECOSYSTEMS Understand populations and communities.
(ROOT (S (PP (IN Unlike) (NP (NN energy))) (, ,) (NP (NN matter)) (VP (VBZ does) (RB n't) (VP (VB need) (S (VP (TO to) (VP (VB be) (VP (ADVP (RB constantly)) (VBN added) (PP (TO to) (NP (NNS ecosystems))))))) (SBAR (IN because) (S (NP (PRP it)) (VP (VBZ is) (VP (VBN recycled) (PP (IN through) (NP (NNS ecosystems))))))))) (. .)))