internal source of pollution

• 内源污染

internal source of pollution的用法和样例：

例句

1. Soil erosion and non-point source pollution are two serious environmental issues.
   土壤侵蚀与非点源污染是两大重要的环境问题。
2. So the agricultural non-point source pollution has been considered as the main pollution source of eutrophication.
   因此农业面源污染已被视为水体富营养化的主要污染源。