Many recalcitrant organic molecules are naturally degraded in the soil.
Many recalcitrant organic molecules are naturally degraded in the soil.
很多顽强的有机分子，在土壤中都自然地被降解了。
Many recalcitrant organic molecules are naturally degraded in the soil.
很多顽强的有机分子，在土壤中都自然地被降解了。