Final answer:
The dissolved load carried by a river consists of various substances that have been dissolved in the water, including nutrients, pesticides, and minerals.
Step-by-step explanation:
The dissolved load carried by a river consists of various substances that have been dissolved in the water. These substances can include nutrients, such as organic nitrogen and phosphorus, as well as pesticides and minerals. When rain or snow waters fall, they interact with vegetation, top soil, bedrock, riverbeds, and lakebeds, dissolving whatever is soluble. These dissolved substances contribute to the overall composition of river water.