What factors might runoff pick up before it drains into oceans?

Runoff plays a crucial role in transporting materials from land to oceans. One significant aspect of runoff is its ability to pick up various pollutants, including pesticides. These substances can originate from agricultural activities where pesticides are used to control pests on crops. When it rains or when snowmelt occurs, these chemicals can be washed away from fields, gardens, or urban areas and carried into waterways, eventually making their way to the ocean. This transfer can have harmful effects on marine ecosystems, as these pollutants can adversely affect the health of aquatic life.

While natural materials like rocks and soil, salts, minerals, and organic matter such as algae and aquatic plants may also contribute to runoff, the specific focus on pollutants highlights the impact human activities have on water quality as it enters marine environments. This aspect is critical, especially concerning environmental conservation efforts aimed at reducing pollution and protecting marine habitats.