Write short notes on the following: (a) soil pH; (b) soil texture; (c) soil organisms; (d) soil profile.
a) Soil pH: Soil pH is a measure of the acidity or alkalinity of soil. It is a very important factor for plant growth because it affects the availability of essential nutrients to plants. The pH scale ranges from 0 to 14, with 7 being neutral. A pH value below 7 indicates acidic soil, while a pH value above 7 indicates alkaline soil. Most plants grow well in soil with a pH between 6 and 7.5.
b) Soil texture: Soil texture refers to the proportion of sand, silt, and clay particles in the soil. It is an important characteristic of soil because it affects soil water-holding capacity, nutrient availability, and aeration. Sandy soils have large particles and drain water quickly, while clay soils have small particles and hold water and nutrients more effectively. Loam soils have a mixture of sand, silt, and clay particles and are ideal for plant growth.
c) Soil organisms: Soil organisms refer to the living organisms that inhabit soil, including bacteria, fungi, insects, worms, and rodents. They play a vital role in soil fertility by decomposing organic matter, cycling nutrients, and improving soil structure. Some soil organisms are beneficial to plants, while others can be harmful.
d) Soil profile: Soil profile refers to the vertical arrangement of soil layers or horizons. It is an important characteristic of soil because it provides information about the soil's physical and chemical properties. The soil profile is composed of several horizons, including the topsoil, subsoil, and parent material. The topsoil is the upper layer of soil, where most of the organic matter and nutrients are found. The subsoil is the layer beneath the topsoil, where minerals are found. The parent material is the layer at the bottom of the soil profile, which is made up of rocks and minerals.