Soil Mixtures

     Hi readers, for this entry I will share with you about week 3. I woke up in the early morning and get ready to do for this week activities. As usual, all students FPA gathered at assembly site at the morning. In this week, our (class 2F-2J) activity was soil mixtures. First of all, we learned  the basic knowledge about soil. Mr. Nuruddin was briefed to us about soil mixture.

3.1 Sir Nuruddin explained to students about soil mixtures

    For your information, Topsoil or surface soil is the major zone of root development for crop plants. It contains many of the nutrients available to plants and supplies much of the water necessary for their growth. The subsoil is those layers underneath the topsoil. It contains low organic matter and stores much of the water needed by plants. Mineral soils consist of four major components: inorganic or mineral materials, organic matter, water and air. The solid mineral particles comprise about 45% of the soil volume and organic matter 5%. An optimum moisture for plant growth, the pore space is divided roughly in half, 25% of the volume being water space and 25% air. The volume of composition highly varies with soil types. Air and water contents in soils are more variable.

Major Component of Mineral Soils  

3.2 Volume composition of a loam surface soil when in good condition for plant growth

1.     Soil Organic matter comprises an accumulation of partially disintegrated and decomposed plant and animal residues and other organic compounds synthesized by the soil microbes as the decay occurs. The OM content of a typically well-drained mineral soil is small varying from 1 to 6% by weight of the topsoil and even less in the subsoils. It is an important source of plant nutrients and increases the soil’s ability to hold water. 
2.    For soil Water, water is held in the soil pores with varying degrees of tenacity depending on the amount of water present and the size of the pores. Together with its soluble constituents, including nutrient elements (e.g. nitrogen, phosphorus, potassium, calcium), soil water makes up the soil solution. The soil solution contains small amount but significant quantities of soluble inorganic and organic compounds, some of which contain elements that are essential for plant growth. One other critical property of the soil solution is its acidity and alkalinity.Not all soil water is available to plants. Soil water provides the moisture for chemical reactions.  
3. For soil Air, the content and composition of soil air are determined largely by the water content of the soil, since the air occupies those soil pores not filled with water. Some gases are consumed by plant roots and by microbial reactions while others are released. Therefore the composition of soil air is quite dynamic.  Carbon dioxide in soil air is often several hundred times higher than the 0.03% commonly found in the atmosphere. Oxygen decreases accordingly, may be lesser than of the 20% for normal atmosphere.

     We applied ratio of 3:2:1 based on standard nursery for soil mixture. Number 3 refer to top soil, number 2 refer to organic matter, and number 1 refer to sand. organic matter influences the most important soil properties such as nutrient and water holding capacity, structure, hence fertility.

                                                         Function of organic matter:
– Organic matter can hold up to 20 times its weight in water (increase water holding capacity)
– Permits exchange of gases, stabilizes structure (aggregate formation)
– buffering in slightly acid, neutral and alkaline ranges-leading to uniform pH
– 30-40 % of CEC
– Source of nutrients
           
     Before we mix the soil, we learned how to fold and make base correct base for the polybag. It is important to know this step so that the soil can occupied  the whole space at the bottom of polybag.

3.3 Students from class 2G managed to fold polybags.

After that, we mix the soil according to the ratio 3:2:1. Chicken dung was used as the organic matter.

3.4 Some of us mixed all the mixtures based on ratio 3:2:1

Finally, the soil mixtures inserted into the polybag and we divided and insert that mixtures into 5 small polybags.

3.5 The soil mixtures were inserted into small polybag.

In this week, I learned new things and some information about soil mixture. Actually there are a lot ratio that we can use for soil mixture. But, 3:2:1 is the best ratio for nursery activity. I hope you enjoy to read this entry. Thank you for visit my blog and see next entry.