Second Lab Report : "Ulam Raja"

FACULTY OF SCIENCE AND NATURAL RESOURCES

SS11403 SAINS TANAH SEKITARAN

SEMESTER 2 2017/2018

Date of Submission: 27th March 2018

MRS. DIANA DEMIYAH BINTI MOHD HAMDAN

TITLE : 'ULAM RAJA'

NAME	IC NUMBER	MATRIC NUMBER
MOHD FATHULIZZAT BIN ASFI	970528125555	BS17110533
CHIN JIA HUI	970616125600	BS17110550
RINA BINTI SARIKA	981008125096	BS17110233
MAIZATUL AKMAR BINTI MOHAMAD NIZAM	970130235172	BS17110366
NORFARAH A'AINA BINTI BAHARIN	980118126298	BS17160676
NOOR HIQMAH BINTI MASBOL	980607015214	BS17110045

INTRODUCTION

Soil varies in its composition and the structure of its particles, and these factors are closely examined by farmers, who need appropriate soil for planting crops, as well as engineers who may need to understand how soil is going to hold up under different demands. Soil is also vitally important to the sustainability of an ecosystem because it serves as the natural medium for the growth of vegetation. There are some chemical properties that can help the farmer for better planting which is the soil pH and water holding capacity.

The term pH is used to indicate the level of acidity or alkalinity of a soil. Below pH 7, the soil are term acid and above 7, the soil are term alkaline. The pH is one of the most important properties involved in plant growth, as well as understanding how rapidly reaction occur in the soil. The range of soil pH is between 3-8 pH and most world soil are between 5.5-7.5. Earthworm is prefer to low pH which is acidic while the other organism mostly prefer to high pH which is alkaline. The pH can be manage by human where they can add things to soil to change them to better suit plant. The ideal soil range is near to natural pH which is 7. 7 pH has the highest nutrients that needed for the plant growing such as nitrogent, potasium, phosporus, calcium and magnegium. The acidic soil between 3-5 pH, it rich with heavy metal for examples, iron, manganase, boron, copper and zink. Low pH soils result in an increase in Aluminium. Aluminuim is toxic to plants. It will affect the activities of soil microorganisms, thus affecting nutrient cycle and disease risk. 

The water holding capacity of a soil is a very important agronomic characteristic. Soils that hold generous amounts of water are less subject to leaching losses of nutrients or soil applied pesticides. This is true because a soil with a limited water holding capacity such a sandy loamreaches the saturation point much sooner than a soil with a higher water holding capacity such a clay loam. After a soil is saturated with water, all of the excess water and some of the nutrients and pesticides that are in the soil solution are leached downward in the soil profile.

Soil water holding capacity is controlled primarily by the soil texture and the soil organic matter content. Soil texture is a reflection of the particle size distribution of a soil. An example is a silt loam soil that has 30% sand, 60% silt and 10% clay sized particles. In general, the higher the percentage of silt and clay sized particles, the higher the water holding capacity. The small particles of clay and silt have a much larger surface area than the larger sand particles. This large surface area allows the soil to hold a greater quantity of water. The amount of organic material in a soil also influences the water holding capacity. As the level of organic matter increases in a soil, the water holding capacity also increases, due to the affinity of organic matter for water.

OBJECTIVES

1. The students can determine the amount of water holding capacity in five different soils. The water holding capacity is different from each type of soil as it also affects the moisture value of soil.
2. The students can determine the pH value of soil. Identify the relationship between soil pH and how pH value affects the rate of plant growth.
3. The students can make a relationship between the water holding capacity, soil pH value and how they affect the rate of plant growth.

  

PROCEDURE :

SOIL MOISTURE

1. Before watering the plant,the soil moisture of the plant soil was checked using the portable soil moisture tool.
2. Then, the soil pH meter was used to check the soil pH.
3. Check the soil moisture that were air dry previous lab week.
4. If it was not completely dried out, put the soil sample in the oven and heat up at 80 degrees Celsius for about one hour and check again.
5. After soil is completely dried out,the dry soil was weighed.

SOIL PH

1. A few spoonful of soil into a jar/beaker was transferred and stir solution mixed with deionized water.
2. The solution was filtered into a folded filter paper place on a funnel sitting on a test tube.
3. The pH paper was used to test the pH of each soil solution.
4. The pH paper was dipped into the soil solution and take it out to dry for a while.

*Note the colour and compare with the chart.

5. Photos of the result was taken.
6. The filter solution pH was checked using the soil pH meter in the lab.
7. 3 methods was used to check the soil sample pH.

SOIL WATER HOLDING CAPACITY

1. A filter paper was taken and place it at the bottom of the tin box.
2. The tin was weighed along with the filter paper.
3. Some soil was taken and transferred into the tin box. (Make sure all sample soil tested have the same amount of volume.
4. All soil sample was tested. If only one soil sample type it was done two times.
5. The soil was pressed gently as compact as possible until a uniform layer on top.
6. The tin box was weighed with soil and its weight was noted.
7. A water was poured into a weight plastic container and two small plastic rod was placed  to support the tin box float in contact with water.
8. The tin box was left undisturbed until water surface on top of the soil and soil is moist.
9. The tin box was lifted and dripping water was wiped from the tin box bottom before measure the weight.

RESULT AND OBSERVATION

SOIL PH AND SOIL MOISTURE

RESULT :

Soil sample	pH	pH meter	pH paper	Moisture
Ground soil	6.78	5.52	5	3.5
Wetland	6.70	6.28	5	1.4
Red soil	6.80	4.62	4	2.5
Hill Soil	6.40	6.27	5	5.5
Sand	6.20	5.93	6	5.1

SOIL WATER AND HOLDING CAPACITY

RESULT :

Soil Sample	Weight of Tin	Weight tin + Filter paper (A)	Weight tin + Filter paper + soil sample (B)	Weight tin + Filter paper + wet soil (D)	Weight dry soil B – A = C	Weight wet soil D – A = E	Mass water absorb by soil E – C = N	% of water holding capacity
Hill soil	9.2654	9.8218	90.0982	139.5442	80.2764	129.7224	49.446	38.12 %
Red soil	8.9680	9.5226	95.2517	127.1089	85.7291	117.5863	31.8572	27.09 %
Ground soil	9.4315	9.9899	74.1234	132.4908	64.1335	122.5009	58.3674	47.65%
Wetland	9.4318	9.68805	94.0360	137.1569	84.1555	127.2764	43.1209	33.88%
Sand	9.5189	10.0856	83.7075	113.9425	73.6219	103.8569	30.2350	29.11 %

We can calculated the percentage of water capacity by using this formula :

N/E X 100

N = mass water absorb by soil

E = Weight of wet soil

DISCUSSION

SOIL MOISTURE

Soil moisture is the water that is held in the spaces between soil particles. Moisture content is the quality of water contained in a material such as soil, rock, ceramics, crops or wood. Water content used in a wide range of scientific and technical areas. The volume of soil moisture is small; nonetheless, it is fundamental importance to many hydrological, biological and biogeochemical processes. Soil moisture information is valuable to a wide range because it concerned with weather, climate, runoff potential, flood control, soil erosion, slope failure, reservoir management, geotechnical engineering and water quality. Soil moisture is a key variable in controlling the exchange of water and heat energy between the land surface and the atmosphere through evaporation and plant transpiration.

          

       All five types of soil from Outdoor Development Centre, UMS Peak, Bukit Kokol, lake at Faculty of Science and Natural Resources and Excellent Residential Collage are all weighted 100g and left the soils at five different plastic plates where it has large surface area for one week duration. After one week, the soils are weight again and record the different. The different weight of soil before and after one week shows the how much water content in the soil that has been lost through evaporation. The water content of in soil is 12.9898g, red soil is 7.6622g, ground soil is 28.9509g, wetland soil is 9.2524g and sand soil is 19.1353g.

       From the experiment, the red soil shows the lowest water content among the five types of soil because red soil is low water holding capacity. Red soil is a type of soil that develops in a warm, temperate, moist climate under deciduous or mixed forest as it having thin organic-mineral layers overlying a yellowish-brown leached layer resting on an alluvial red layer. As the red soils are generally derived from crystalline rock.The soil that has most water content is ground soil which it has high water holding capacity. The ground soil is usually can be found in terrestrial forest where the water is absorbed on the Earth. As the ground water also rich with nutrient and well-drained spaces.

     Soil moisture measurements in agricultural settings provide important information for drought early warning. The upper 200 centimetres of soils is classified as the “root zone soil moisture” and is important for describing the water that is available to plants. When drought occurs, there is a deficit amount of moisture in the root zone, and consequently crop productivity diminishes. Having continuous soil moisture measurements will lead to improved crop yield forecasting, and irrigation planning.

     Soil moisture measurements also are important for predicting floods. By assessing how wet the soil is before a rainstorm, we can predict the potential for flooding to occur. If the soil is already oversaturated, at its maximum water-holding capacity, a rain event will not be absorbed adequately through the soil and flooding will likely occur.

     Currently, weather prediction relies more heavily on observing the moisture levels in the atmosphere, instead of observing the moisture levels of soils; yet this is mostly due to the lack of soil moisture data available. Having soil moisture measurements may provide for a more accurate weather forecast. For example, soil moisture measurements could provide meteorologists with information on the amount of water available to evaporate from the land surfaces, which are directly related to weather and climate forecasting.

    Soil moisture links together the water, energy, and carbon exchanges between the land and the atmosphere. Observing soil moisture measurements allows for an assessment of the entire Earth system, and analysing global changes is extremely important for understanding future climate change impacts.

SOIL PH 

Soil pH or soil reaction is an indication of the acidity or alkalinity of soil and is measured in pH units. Soil pH is defined as the negative logarithm of the hydrogen ion concentration. The pH scale goes from 0 to 14 with pH 7 as the neutral point. As the amount of hydrogen ions in the soil increases the soil pH decreases thus becoming more acidic. From pH 7 to 0 the soil is increasingly more acidic and from pH 7 to 14 the soil is increasingly more alkaline or basic. 

      Using a strict chemical definition, pH is the negative log of hydrogen (H+ ) activity in an aqueous solution. The point to remember from the chemical definition is that pH values are reported on a negative log scale. So, a 1 unit change in the pH value signifies a 10-fold change in the actual activity of H+, and the activity increases as the pH value decreases. To put this into perspective, a soil pH of 6 has 10 times more hydrogen ions than a soil with a pH of 7, and a soil with a pH of 5 has 100 times more hydrogen ions than a soil with a pH of 7. Activity increases as the pH value decreases. 

      From the experiment, soil pH provides various clues about soil properties and is easily determined. The most accurate method of determining soil pH is by a pH meter. A second method which is simple and easy but less accurate then using a pH paper. The result shown that pH of each types of the soil after tested using pH meter and pH paper were not almost accurate to each other. A pH meter usually has a computer or a digital user interface. You can calibrate it by using standardized buffers which allow the meter to associate a particular voltage with a pH value. There are subtle differences between pH meters, but they are generally accurate at least to the hundredths place. These meters can be sensitive to ion interference, from various ions in the solution you are testing, and may drift from their calibrated position after some time. As long as you treat them with care, calibrate them regularly, maintain them according to the manufacturer's recommendation, and store them correctly, you can expect a pH meter to be accurate and durable. 

     Besides, The use of pH paper is similar to the use of a Galileo thermometer. Particular colors indicate certain values, and each measurement is only accurate within a unit or two. While pH paper is great for quick qualitative work, it fails at highly accurate quantitative work. If the accuracy you desire is within one pH value or two, paper is the way to go. Litmus paper can give you a quick check to see if your solution is acidic, neutral or basic. That is one place pH paper shines. On a side note, pH paper will be difficult to work with accurately if you are color blind. 

      As we can see from the result, the pH of wetland soil is the most suitable range among the the other soil which is 6.28, and followed by hill soil (6.27), sand (5.93), ground soil (5.52) and red soil (4.62) after being tested by pH meter. Meanwhile, the pH of sand is the most suitable range among the the other soil which is (6), and followed by hill soil, ground soil and wetland soil which is (5) and lastly the red soil (4) after being tested by pH paper. 

     There may be considerable variation in the soil pH from one spot in a field or lawn to another. To determine the average soil pH of a field or lawn it is necessary to collect soil from several locations and combine into one sample. Soil pH also influences soil-dwelling organisms, whose well-being, in turn, affects soil conditions and plant health. The slightly acidic conditions enjoyed by most plants are also what earthworms like, as do microorganisms that convert nitrogen into forms that plants can use.

Table 1. Soil pH and Interpretation
5.0	5.5	6.0	6.5	7.0	7.5	8.0
Strongly acid	Medium acid	Slightly acid	Neutral	Neutral	Mildly alkaline	Moderately alkaline
			Best Range for Most Crops

WATER HOLDING CAPACITY

The determination of water holding capacity in soils is important as it gives an ideas to us to know the capacity of the soil to hold water for the use by the crops. The light soils which do not hold such water require more frequent irrigations than heavy clay soils. Futhermore, well decomposed organic matter increases the water holding capacity. water holding capacity of soils is useful for selection of soils for irrigability classification and it also can helps us for comparing other properties that contain the soils.

Soils with smaller particles which is silt and clay have a larger surface area than those with larger sand particles. Beside that, as we known a larger surface area can allows a soil to hold more water. In other words, a soil with a high percentage of silt and clay particles which describes fine soil has a higher water holding capacity. The addition of organic matter to the soil usually can increase the water holding capacity  of the soil. This is because the addition of organic matter increases the number of micropores and macroporesin the soil either by ‘gluing’ soil particles together or creating favourable living conditions for soil organisms. Certain types of soil organic matter can hold up to 20 times their weight in water (Reicosky , 2005).

From the experiment, the result shown that weight of each types of the soil not almost accurate to each other. This is because analytical balance machine very sensitive with the changes in the air pressure and air movement causes by people passing by and air conditioning. As we can see from the result, ground soil holds the highest percentage of water holding capacity. Then, following by hill soil, wetland, sand soil and lastly is red soil. we can concluded that ground soil can allow a soils hold more water than the others type of soils. This means that ground soil have a high quality of soil compares to others type of soil.

We can calculate the percentage of water holding capacity by mass of water absorb by soil divided with weight of wet soil times 100 %. The weight of wet soil we can get from combination weight of tin, filter paper and the wet soil (D) minus with the combination weight of tin and filter paper (A).

CONCLUSION

Soil pH is a measure of the acidity or basicity of a soil.A soil with a pH number below 7 is acid, while one with a pH above 7 is alkaline. As the result of this experiment, the pH for all the selected soil sample are bellow 7, which indicate all of the soil sample are acidic soil. There 3 method to determine the pH of soil sample, which include, pH paper , pH meter and soil moisture meter. Based on the result by using pH meter, red soil is the type of soil which is the most acidic among the soil sample, the pH meter show 4.62. Where for the least acidic is the wetland which only show 6.28.Soil water holding capacity refer to the ability of soil to Water in field capacity. By using the formula N/E X 100%, where N is the mass of water and E is the weight of wet soil, the percentage of water holding capacity can be calculated. Generally, sandy soils tend to have low water holding capacity which indicate sandy soil less able to hold and store water. Yet, based on the result obtained, red soil shows the lowest water holding capacity and follow by sand, which is 27.09% and 29.11% respectively. While for ground water shows 47.65% of water holding capacity which is the highest result obtained among the soil sample.

REFERENCES

1. AGVISE Laboratories, 2018. The understanding of water holding capacity. Retrieved from : https://www.agvise.com/educational-articles/water-holding-capacity/
2. Charman. 1998. Soils : their properties and management , 5Th ed. Oxford University Press. Melbourne. 
3. Plaster , E. J . 1996 . Soil science and management . 3rded. Albany : Delmar Publisher . 
4. Ron Goldy. 2011. Understanding soil pH Part I. Retrieve from: http://msue.anr.msu.edu/news/understanding_soil_ph_part_i