( ( ( ( ( ( Nutrient cycling ) -- ) especially ) , ) ( ( nitrogen cycling ) ( It ( ( 's true ) ( that ( carbon ( is ( ( the ( chemical backbone ) ) ( of ( ( living things ) ( on ( this planet ) ) ) ) ) ) ) ) ) ) ) ) . )
(ROOT (NP (NP (JJ Nutrient) (NN cycling)) (: --) (ADVP (RB especially)) (, ,) (NP (NP (NN nitrogen) (NN cycling)) (SBAR (S (NP (PRP It)) (VP (VBZ 's) (ADJP (JJ true)) (SBAR (IN that) (S (NP (NN carbon)) (VP (VBZ is) (NP (NP (DT the) (JJ chemical) (NN backbone)) (PP (IN of) (NP (NP (VBG living) (NNS things)) (PP (IN on) (NP (DT this) (NN planet))))))))))))) (. .)))
Nutrient cycling -- especially, nitrogen cycling It's true that carbon is the chemical backbone of living things on this planet.
(ROOT (S (NP (DT The) (NN nitrogen) (NN cycle)) (VP (VBZ includes) (NP (NP (NN air)) (, ,) (NP (NN soil)) (, ,) (CC and) (NP (VBG living) (NNS things)))) (. .)))