Agricultural plastic mulch is a method of soil conservation that involves covering the soil with a thin layer of plastic to reduce weed growth, retain moisture, and regulate soil temperature. Unlike other soil conservation methods such as contour farming, terracing, or crop rotation, plastic mulch is a non-biological approach that doesn't involve changing the landscape or crop patterns. It's more about managing the microclimate around the plants. Other methods like cover cropping or no-till farming focus on building soil health and reducing erosion through biological means. Plastic mulch is often used for specific crops and seasons, while other conservation methods are more general and can be applied to a variety of agricultural settings.