( Ecoregions ( ( are ( classified ( by ( ( ( biome type ) , ) ( which ( are ( ( the ( major ( global ( plant communities ) ) ) ) ( determined ( by ( ( rainfall and ) climate ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Ecoregions)) (VP (VBP are) (ADJP (VBN classified) (PP (IN by) (NP (NP (JJ biome) (NN type)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBP are) (NP (NP (DT the) (JJ major) (JJ global) (NN plant) (NNS communities)) (VP (VBN determined) (PP (IN by) (NP (NNS rainfall) (CC and) (NN climate)))))))))))) (. .)))
Ecoregions are classified by biome type, which are the major global plant communities determined by rainfall and climate.
(ROOT (S (NP (JJ Terrestrial) (NNS biomes)) (VP (VBP are) (VP (VBN classified) (PP (IN by) (NP (NP (JJ climatic) (NNS factors) (CC and) (NNS types)) (PP (IN of) (NP (JJ primary) (NNS producers))))))) (. .)))
Terrestrial biomes are classified by climatic factors and types of primary producers.