Soil Chemistry

1. Rashtrapita Mahatma Gandhi Art’s and Science College,
Nagbhid Dist.- Chandrapur
Online Webinar
Dr. Ganesh D Satpute
Head Dept. of Chemistry
Shri. Govindrao Munghate College,
Kurkheda Dist.- Gadchiroli
Resource Person

2. Soil Chemistry
• Introduction of Soil.
•Types of Soil
• Collection of soil Samples
• Analysis of Various Soil Parameter.

3. What is soil ?
Soil is composed of small rock particles in a mixture form and contains organic
materials / humus which develops on the earth surface and tends to support
plant growth. Soil is rich in number of contents such as organic matters,
minerals, gases, liquids, and innumerable organisms. Hence, soil is termed as
dynamic, living matrix maintaining the terrestrial ecosystem which actually
acts as “Skin of the Earth”. Soil not only supports the agricultural base but also
supports many other plant lives available on wonder planet “Earth”.
How Does Soil Form?
It take long time for soil to form.
Soil form as rock is broken down by wethering and
mixes with other material on the surface.
Soil is constantly being formed every time bedrock is
exposed. Over time, soil developed layer. We call
these layer horizons.

4. Type of Soils in India
Survey of India (1956) has recognized Indian soils into six different types-
1) Alluvial Soil: This soil has originated from river sedimentation and
remains rich in humus and hence is fertile. This soil gets renewed every year
and common in India (43% of total). This soil is spread across Great
northern plain, lower valleys of Narmada, Tapti and goes up to northern
Gujarat.
Features: It appears light grey to ash grey in colour. In texture it remains
sandy to silty loam or clay and rich in potash but poor in phosphorous.

5. 2) Red Soil: This soil has originated by weathering of rocks. It is common in
low rainfall area. The red texture is because of heavy iron content than
normal and it appears as yellow or brown with low content. The soil is
prominent in Maharashtra, Tamil Nadu, Andhra Pradesh, Chhattisgarh, and
Karnataka and in few regions of Orissa.
Features: The soil is rich in ferric oxide and sandy to clay and loamy in
texture. These soil shows deficiency of phosphate, manganese, nitrogen,
humus, lime and potash. Major crops cultivated are cotton, wheat, pulses,
tobacco, oilseeds, potato etc.
.

6. ++++
3) Black Soil: Soil especially found in Maharashtra, Madhya Pradesh,
Chhattisgarh, Gujarat, Andhra Pradesh and Tamil Nadu. These soils called as
“Regure Mruda” (cotton).
Features: Soil is deep black to light black with clay like texture and rich in
iron, lime, calcium, aluminum, potassium and magnesium and rated
deficient in nitrogen, phosphorous and organic matter.
.

7. +
4)Laterite Soil: The soil is major in regions of high temperature and high
rainfall. The main areas in India are Kerala, Maharashtra, Tamil Nadu,
Chhattisgarh and some hilly areas of Assam and Orissa. Its Latin word
‘later’ means Brick which features soft nature when wet and hard as it
becomes dry.
Features: Soil remains red in color due to ferric oxide and is rich in iron and
aluminum and deficient in potash, potassium, lime, nitrogen and humus.
Major crops cultivated are rice, ragi, cashew and sugarcane.
.

8. 5) Mountain Soil: These soils are produced by accumulation of organic
matter derived from forest growth and vary in different region as per
altitude. This soil is used to grow tea. This is immature soil with low humus
and remains acidic.
Features: These soils are occupying about 8% of the total land area of India.
These soils are heterogeneous in nature and their character changes with
parent rocks and climate.
.

9. A
6) Desert Soil: In a desert region like Rajasthan, soil remains mostly
undeveloped as evaporation is higher than actual rainfall that leads to excess
of salt content and saline layer which forms a hard crust. Mainly these soils
are sandy and remain deficient in organic matter. Majorly observed in Arid
and Semi-Arid conditions and deposited mainly by wind activities.
Features: This soil is rich in salt, It is rich in Kankar or impure calcium
carbonate makes water infiltration difficult into the soil. Soil remains red to
brown in color.
.
.

10. Collection of Soil Samples
* Sampling tools:
Samples were collected by using stainless steel auger and khurpi. Khurpi was
also used for scrapping away surface litter or any stone etc.
* Depth of sampling:
The depth of soil sampling was considered up to 10-15 cm as the rice roots
reach up to 10-15 cm in soil.
* Sampling Process:
0 0 0
0 0 0
Zigzag Manner
* Precaution for collection of soil sample:

12. * Information sheet:
A tag used on each bag mentioned with following details:
1) Sample Number (No.)
2) Date of collection
3) Name of cultivation
4) Address, Tehsil (Villages)
5) Type of soil
6) Survey Number (No.)
7) Proposed crop and variety

13. Analysis of Soil Samples

18. Introduction-