AP BIOLOGY

Detailed explanation-1: -Organic soil: Holds and retains water more efficiently than non-organic soil. Is nutrient-rich.

Detailed explanation-2: -The surface soil, or topsoil layer (O and A horizon in Figure 1–2), usually contains less clay, but more organic matter and air, than the lower soil layers. Topsoil is usually more fertile than the other layers and has the greatest concentration of plant roots.

Detailed explanation-3: -Here are some of the things that soil organic matter does for your soil: Provides essential nutrients for plants (such as nitrogen, phosphorus and sulfur) as it is decomposed by microbes. Feeds and provides habitats for diverse soil organisms, including those that help fight plant pests and diseases.

Detailed explanation-4: -Final answer: “It (organic manure) has a balance of all plant nutrients” is the incorrect statement regarding organic manure.