Introduction
- Soil is a complex and dynamic system composed of various essential elements and organisms that interact in intricate ways.
- The components of soil form the foundation of our terrestrial ecosystems, playing a pivotal role in supporting plant life, maintaining environmental balance, and influencing the well-being of both natural and human-made environments.
- Components of soil is fundamental to agriculture, ecology, environmental science, and land management.
- We will now explore the primary components of soil and their significance in shaping the Earth’s surface and sustaining life on our planet.
Composition of soil on volume basis (Soil components)
Soil = Mineral matter : 45% + Organic matter : 5% + Soil water : 25% + Soil air : 25%
1. Mineral Matter (45%) :
- Primary + Secondary minerals.
- Having definite chemical composition and crystalline structure.
a. Primary minerals :
- Also called as Skeletal Minerals.
- Mostly concentrated in coarser fraction.
- E.g. Quartz and Feldspar
b. Secondary minerals :
- Concentrated in finer fraction – (Clay Fraction)
- Size less than 2 micron
- E.g. Silicate clay, oxides of Fe and Al.
2. Organic Matter (5%) :
- Act as an Chelating Agent (Bind the soil particle)
- Organic matter content in soil varies from 3-5% by weight.
3. Soil Water (25%) :
- Soil Solution – Soil Water + Dissolved Salts.
- Soil Solution supply different essential plant nutrients.
4. Soil Air (25%) (% by volume) :
| Gas | Soil Air | Atmosphere |
| Oxygen | 20 | 21 |
| Nitrogen | 78.60 | 78.03 |
| CO2 | 0.30 – 0.50 | 0.03 |
| Argon | 0.90 | 0.94 |
Approaches of Soil Study :
1. Pedology :
- Greek word pedon, means soil or earth
- Pedology treats soil as a natural body, weathered and synthesized product in nature
- The origin of the soil, its classification and its description are examined in Pedology.
- Pedology is the study of soil as a natural body and does not focus on the soil’s immediate practical use.
- A pedologist studies, examines and classifies soil as they occur in their natural environment.
2. Edophology :
- Greek word edaphos, means soil or ground
- Edaphology treats soil as a medium for plant growth.
- It is the study of soil from the stand point of higher plants.
- Edaphologists consider the various properties of soil in relation to plant production.
- They are practical and have the production of food and fiber as their ultimate goal.
- They must determine the reasons for variation in the productivity of soils and find means for improvements.
Conclusion
In conclusion, soil is a complex and dynamic ecosystem composed of various essential components that collectively support plant growth and influence the overall health of the environment.Understanding and managing these soil components are essential for sustainable agriculture, environmental conservation, and maintaining healthy ecosystems. Soil management practices, such as crop rotation, organic matter addition, and pH adjustment, are crucial for optimizing soil health and productivity. Protecting and preserving soil resources is critical for ensuring food security and the long-term well-being of our planet.