1.Differentiate between soil permeability and retentivity.
2.Differentiate between chemical factors and biological factors of soil organisms.
Please note,I wouldn't be needing any information from: Soil-Wikipedia,the free Encyclopedia.
Thanks.
1. To differentiate between soil permeability and retentivity, you do not need to rely on specific information from Wikipedia. Permeability and retentivity are two distinct properties of soil related to its ability to hold and transmit water. Here's an explanation of each:
a) Soil Permeability: This refers to the ability of the soil to allow water or other fluids to pass through it. It represents the ease with which water can infiltrate or move through the soil. Permeability is influenced by factors such as soil texture, structure, composition, and the presence of macropores or fractures. You can evaluate the permeability of a soil by conducting a simple experiment:
1. Take a small column or cylinder with a known volume and line it with a filter paper.
2. Fill the column with the soil sample you want to test.
3. Slowly pour water into the column and measure the rate at which it passes through the soil.
4. The time it takes for the water to complete its passage through a known length of the soil column will help you determine the permeability of the soil.
b) Soil Retentivity: This refers to the ability of the soil to hold or retain water. It measures the soil's capacity to retain moisture for use by plants. Soil retentivity is influenced by factors such as soil texture, organic matter content, compaction, and the presence of micropores or colloids. A simple experiment to assess soil retentivity can be done as follows:
1. Take soil samples from different locations with a known initial moisture content.
2. Place the soil samples in containers or weigh them and record their initial weights.
3. Allow the soil samples to sit exposed under the same environmental conditions for a specific period.
4. After the specified time, reweigh the soil samples to determine the moisture loss.
5. The difference in weight before and after drying helps to estimate the soil's retentivity.
2. Differentiate between Chemical Factors and Biological Factors of Soil Organisms:
Chemical factors and biological factors are two broad categories that affect soil organisms differently. Here's an explanation of each:
a) Chemical Factors: These refer to the chemical characteristics of the soil that influence the growth, survival, and activity of soil organisms. Chemical factors can include:
1. pH: The acidity or alkalinity of the soil affects the species composition and metabolic activities of soil organisms.
2. Nutrient Availability: Soil organisms require essential nutrients such as nitrogen, phosphorus, and potassium for their growth and metabolism.
3. Soil Organic Matter: Organic matter provides energy and nutrients to soil organisms, while also improving soil structure and water holding capacity.
4. Soil Contaminants: Certain chemicals, such as heavy metals or pesticides, can have toxic effects on soil organisms, disrupting their ecological functions.
b) Biological Factors: These refer to the specific interactions among different soil organisms and their impact on soil properties and nutrient cycling. Biological factors include:
1. Soil Microbes: Microorganisms such as bacteria and fungi play crucial roles in nutrient cycling, organic matter decomposition, and disease suppression.
2. Soil Fauna: Larger organisms, such as earthworms, nematodes, and arthropods, enhance soil structure, nutrient cycling, and organic matter decomposition through their feeding activities.
3. Plant-Soil Relationships: The release of root exudates by plants influences the growth of beneficial soil microorganisms, while also attracting certain predators or pathogens.
By understanding these differences, you can appreciate the various factors that influence soil permeability, retentivity, and the complex interplay between chemical and biological factors impacting soil organisms.