Analytical Detection of Soil Parameters Using PH Measurement, Conductivity Analysis, UV Spectrophotometer, And Incubator

Soil isn’t just dirt it’s actually a complex system made up of three parts: solids (like minerals and organic matter), liquids (mainly water), and gases (the air in between the particles). All of these works together to form what we call the soil matrix. Soil forms over time through a mix of different influences things like climate, the shape and slope of the land (called relief), living organisms, and the type of rocks or materials it originally came from (known as parent material). As time goes on, soil keeps changing and developing through natural physical, chemical, and biological processes, including weathering and erosion. Because of how dynamic and interconnected all these processes are, many soil ecologists see soil as more than just a medium—it's a living ecosystem in itself.

Fig. 1 Study Area Sources Google Map

Soil quality is essential for agriculture, plant growth, and environmental health. Several key parameters determine soil health and fertility.  pH is a crucial factor that affects soil chemical properties and nutrient availability. Patel et al. (2011) found that low pH increases soil acidity, harming microbial activity and plant growth. Sharma et al. (2016) and Kumar et al. (2019) showed that acidic soils reduce nutrient availability, leading to poor crop yield. Verma et al. (2014) and Singh et al. (2018) demonstrated that pH imbalance causes nutrient leaching, contributing to soil degradation. Electrical conductivity (EC) measures the concentration of soluble salts in soil, indicating its salinity level. High EC levels reduce plant water uptake and affect crop health. Joshi et al. (2013) explained that EC helps determine soil suitability for agriculture, irrigation, and industrial use. Sodium and potassium content are measured using a flame photometer, calibrated with standard sodium (1–100 mg/kg) and potassium (1–5 mg/kg) solutions. For high concentrations, samples are diluted, and results are adjusted using the dilution factor for precise readings. Microbiological testing of soil assesses microbial contamination and overall soil health. Standard methods are used, including presumptive, confirmed, and completed tests. Mehta et al. (2015) and Rao et al. (2017) highlighted the importance of

MATERIAL AND METHOD:

For this study, we collected soil samples from different locations around Chandwad tehsil to check the quality of the soil.  A total of Three soil samples were taken from places like agricultural fields, gardens, farm, roadsides. Each sample was carefully collected in clean plastic containers and labelled properly. We followed the guidelines recommended by the Food and Agriculture Organization (FAO) and World Health Organization (WHO) to make sure the samples stayed in good condition until they were analysed in the lab.

Parameter Tested:

We checked the soil samples for several important properties, including:

O pH (to know if the soil is acidic or alkaline)

O Electrical Conductivity (EC) (to measure salts in the soil)

O Organic Matter Content (important for soil health)

O Nitrogen (N), Phosphorus (P), and Potassium (K) (essential nutrients for plants)

O Moisture Content

O Bulk Density (how compact the soil is)

O Microbial Activity (bacteria and fungi living in the soil

Procedure: 

1. Measuring pH

We mixed the soil with water, then used a pH meter to check whether the soil is acidic or basic. Before each test, the pH probe was cleaned with deionized water and dried properly.

2. Measuring Electrical Conductivity (EC)

A small amount of soil was mixed with distilled water. A digital meter measured how well the soil solution conducted electricity, which tells us about the salt content.

3. Organic Matter

We used a simple chemical method to find out how much organic matter was in the soil.

4. Nitrogen, Phosphorus, and Potassium (NPK)

Special laboratory methods were used to measure the amount of nitrogen, phosphorus, and potassium, which are vital nutrients for plant growth.

5. Moisture Content

We measured how much water was in the soil by weighing it before and after drying it in an oven.

6. Bulk Density

This was calculated by measuring the weight of dry soil per volume. It helps to understand how compact the soil is.

7. Microbial Activity

We checked how many bacteria and fungi were present by growing them in special plates and counting the colonies.

1) Soil pH

Measured pH: Sample A = 8.0, Sample B = 8.1, Sample C = 8.0.

• Summary: soil is uniformly slightly alkaline (pH ≈ 8.0).

Discussion:

• At pH ~8.0 most nutrients such as iron, manganese, zinc and phosphorus become less available to plants, so deficiency symptoms are possible even if nutrients are present.

• Many common crops prefer near-neutral soil (pH 6.0–7.0); acid-loving crops (blueberries, azaleas, potatoes) will perform poorly.

• Alkalinity can come from parent material, alkaline irrigation water, or low organic matter.

Practical recommendations:

• For the project: treat the soil as slightly alkaline and either select tolerant crops (e.g., barley, beets, brassicas tolerate mild alkalinity) or amend the soil to lower pH.

• To lower pH: add elemental sulfur or acidifying fertilizers (ammonium sulfate) and incorporate organic matter (compost).

Exact application rates depend on soil texture and target pH — I can calculate rates if you provide soil type and target pH.

• Test additional parameters: soil texture, organic matter, electrical conductivity (salinity), and available N-P-K and micronutrients to guide fertilization

2) Conductivity

Measured electrical conductivity (EC): Sample A = 0.28 dS/m,

Sample B = 0.38 dS/m, Sample C = 0.28 dS/m.

• Average EC ≈ 0.31 dS/m.

Discussion

• These EC values are low — well below common salinity thresholds. Soils are non-saline and unlikely to cause salt stress for most crops.

• Sample B is slightly higher than A and C but still in the safe range; the small variation could reflect local differences in fertilizer, irrigation, or soil texture.

• Low EC means limited soluble salt supply; nutrient availability may not be affected by salinity, but low salt does not rule out nutrient deficiencies (total N, P, K and micronutrients still need checking).

Practical recommendations:

• Continue normal cropping and irrigation; monitor EC periodically (especially after fertilizer or saline irrigation) and run a full nutrient analysis if plant growth problems appear.

3) Major Nutrients

Summary and Analysis:

- The data indicates that the values of the three major nutrients are relatively consistent across the three soil samples, with some minor variations.

- Available Nitrogen (N): The values range from 189.41 to 193.18 kg/ha, indicating a relatively narrow range of nitrogen availability in the soil samples.

- Available Phosphorus (P): The values range from 30.54 to 37.63 kg/ha, showing a slightly wider range compared to nitrogen. Sample 2 has a lower phosphorus value compared to Samples 1 and 3.

- Available Potassium (K): The values range from 284.47 to 297.53 kg/ha, indicating a relatively consistent level of potassium availability across the soil samples.

Effect of Readings:

The data suggests that the soil samples have a relatively consistent nutrient profile, with some minor variations. The ranges of the nutrient values can be used to inform decisions about fertilizer application, soil management, and crop selection.

For example:

The relatively narrow range of nitrogen values may indicate that nitrogen-based fertilizers may not be necessary, or that a consistent nitrogen application rate can be used across the soil samples. 

- The slightly wider range of phosphorus values may suggest that phosphorus-based fertilizers could be beneficial for Sample 2, which has a lower phosphorus value.

- The consistent level of potassium availability across the soil samples may indicate that potassium-based fertilizers are not necessary, or that a consistent potassium application rate can be used. Overall, the data provides valuable insights into the nutrient profile of the soil samples, which can be used to inform agricultural management decisions and

3) Micronutrients Status