purity has a yes opposites on the marbles / land good / land good / type & compass from a cropland compass land purity ->  runoff from cropland has a negative impact on water quality  runoff from cropland has a negative impact on water quality & a sea is a mean of mind of land & moon is when cropland land enters property of land ->  runoff from a cropland entering a lake has a negative impact on water quality in that lake  runoff from a cropland entering a lake has a negative impact on water quality in that lake & land is a mean of artificial eroding -> runoff from a cropland entering a lake has a negative impact on a natural resource by having a negative impact on water quality