( However ( , ( ( even ( though ( ( number concentrations ) ( are ( generally low ) ) ) ) ) ( , ( ( ( ( ( the ( volume flux ) ) ( of ( large particles ) ) ) and ) ( ( their effect ) ( on ( the ( underwater ( light field ) ) ) ) ) ) ( ( may ( be significant ) ) . ) ) ) ) ) )
(ROOT (S (ADVP (RB However)) (, ,) (SBAR (RB even) (IN though) (S (NP (NN number) (NNS concentrations)) (VP (VBP are) (ADJP (RB generally) (JJ low))))) (, ,) (NP (NP (NP (DT the) (NN volume) (NN flux)) (PP (IN of) (NP (JJ large) (NNS particles)))) (CC and) (NP (NP (PRP$ their) (NN effect)) (PP (IN on) (NP (DT the) (JJ underwater) (NN light) (NN field))))) (VP (MD may) (VP (VB be) (ADJP (JJ significant)))) (. .)))
However, even though number concentrations are generally low, the volume flux of large particles and their effect on the underwater light field may be significant.
(ROOT (S (NP (NP (DT The) (NN number)) (PP (IN of) (NP (NP (NNS particles)) (PP (IN of) (NP (NP (DT a) (NN substance)) (PP (IN in) (NP (DT a) (VBN given) (NN volume)))))))) (VP (VBZ is) (VP (VBN known) (PP (IN as) (NP (DT the) (NN concentration))))) (. .)))