Soil erosion can be caused by agricultural practices. Match the practice with the proper description. 1. Tilling 2. Heavy livestock grazing 3. Pesticides 4. Surface irrigation a. increase the flow of water over the soil, allowing it to pick up more bits and pieces and carry them away b. clear the soil of ground cover, exposing the soil to more water and wind, increasing erosion. c. topsoil is broken up into fine pieces, making it easier to be carried away by water and wind d. used on crops kill microorganisms in the soil that help bind the soil particles together; without this binding, the soil is easier to carry away