Nutrient pollution, the chemical runoff from farms, is a much bigger worry, he believes.

他认为，更令人担忧的是来自农场的化学物质污染。

Scientists say nutrient pollution runoff from farms is the main problem.

科学家表示，来自农场的养分污染径流是主要问题。

Most of the nutrient pollution comes from farms in the state of Pennsylvania, just north of Maryland. It flows down the Susquehanna River to the bay.

大部分的营养污染来自宾夕法尼亚州位于马里兰州北部的农场。营养污染沿着萨斯奎哈纳河流向切萨皮克海湾。

This is key, because many reefs are overgrown with algae due to nutrient pollution from sewage and fertilizer that runs off of land.

这是关键，因为从陆地流出的污水和化肥造成营养污染， 许多珊瑚礁上长满了藻类。

But, it's far more effective at reducing sediment and nutrient pollution than other, more well-known management practices, like planting vegetation on the banks of rivers to filter sediment before it enters the water.

但是，它在减少沉积物和养分污染方面比其他更有效的方法，更知名的管理实践，例如在河岸种植植被以在沉积物进入水中之前对其进行过滤。