褐煤、腐殖酸、残余植物碎屑和地沥青等是现存有机质的主要类型。

Lignitous coal, humic acid, fragments of plant remnants and asphalt are main forms of existing organic substances.

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褐煤、腐殖酸、残余植物碎屑和地沥青等是现存有机质的主要类型。

Lignitous coal, humic acid, fragments of plant remnants and asphalt are main forms of existing organic substances.

youdao