Second Lab Report: TARAB ARAB Padi Sawah

Lecturer: Madam Diana Demiyah Binti Mohd Hamdan

Date of Submission: 27^th March 2018

Report Contents:     Soil Moisture Analysis

                             Soil Water Holding Capacity Analysis

                             Soil pH Analysis

NAME	MATRIC NUMBER
NG JING JIE	BS17160675
FICKRY JAJURI	BS17160677
NURUL IRINA AK DOUGLAS NYEGING	BS17110050
MARILYN LEANNE MONROE	BS17110366
EMILEY TOMPOK @ MOJINOK	BS17110145
SITI NURAZWANNI BT. WARISHAD	BS17160698

SOIL PH ANALYSIS

INTRODUCTION

    Soil pH is a measure of the acidity and alkalinity in soils and is measured in pH units. pH levels range from 0 to 14, with 7 being neutral, below 7 acidic and above 7 alkaline. The optimal range of pH for most plants is between 5.5 and 8.0; however, many of the plants have their own characteristics to adapt and thrive at pH values outside this range. An acid is a substance that tends to release hydrogen ions (H+) while a base is a substance that releases hydroxyl ions (OH-). The strength of the acid depends upon the degrees of ionization (release of hydrogen ions) of the acid. The acidity of the soil will be greater when there are more hydrogen ions held by the exchange complex of a soil in relation to the basic ions (Ca, Mg, K) held.

          

   Plant growth and most soil processes, including nutrient availability and microbial activity, are favoured by a soil pH range of 5.5 – 8. Acid soil, particularly in the subsurface, will also restrict root access to water and nutrients. There are many factors that can affect the soil pH which are rainfall, nitrogen fertilizers, plants and subsoil acidity. The main cause of soil acidification is inefficient use of nitrogen, followed by the export of alkalinity in produce. Soil pH can affect the availability of plant nutrients, increasing of aluminium in soil as toxic to plants, availability of toxic metals and activity of microorganisms thus affecting nutrient cycle and disease risk.

To determine the soil pH, there are three methods that will be used in this experiment, the universal indicator, soil pH meter and the portable pH meter.

OBJECTIVES

-To determine the pH of the 5 types of soils by using universal indicator, portable pH meter and soil pH meter.

-To relate the suitability of the soil to the plantation of “Tarab Arab Padi Sawah”.

MATERIALS

-Universal Indicator

-Portable pH meter

-Soil pH meter

PROCEDURE

1.     A few spoonful of one soil type was transferred into a beaker and the soil was mixed with deionized water and stirred.

2.     The solution was filtered using a folded filter paper that was placed on a funnel sitting on a test tube.

3.     A universal indicator paper was used to test the pH of each soil solution.

4.     The pH paper was dipped into the soil solution and was left for it to dry.

5.     The colour was noted and compared to the colour chart indicator paper.

6.     The filtered solution was then checked its pH using the portable pH meter in the lab.

7.     Besides, the soil pH was also checked using a soil pH meter by inserting the meter into the depth of the soil.

8.     Step 1 to 6 was then performed on 4 other soil samples.

     RESULTS

Method: Soil pH meter

Source of Soil	First pH reading	Second pH reading	Third pH reading	Average pH reading
UMS Peak	4.8	4.9	5.0	4.9
Blk. B1 Residential College E	4.4	4.6	4.7	4.6
ODEC	6.4	6.6	6.4	6.5
Residential College E, Compound	3.4	4.0	3.4	3.6
Garden Soil	4.0	3.8	4.0	3.9

 Table 1: Soil pH of 5 soil sample using the soil pH meter

Method: Universal Indicator

Source of soil	pH
UMS Peak	5.0
Blk. B1 Residential College E	4.0
ODEC	7.0
Residential College E, Compound	4.0
Garden Soil	4.0

Table 2: Soil pH of 5 soil sample using the universal indicator

Method: Portable pH meter

Source of soil	pH
UMS Peak	5.71
Blk. B1 Residential College E	5.29
ODEC	7.37
Residential College E, Compound	3.93
Garden Soil	5.11

Table 3: Soil pH of 5 soil sample using the portable pH meter

Methods Soil Type	Soil pH meter	Universal Indicator	Portable pH meter	Average pH
UMS Peak	4.9	5.0	5.71	5.20
Blk B1	4.6	4.0	5.29	4.63
ODEC	6.5	7.0	7.37	6.96
Residential College E, compound	3.6	4.0	3.93	3.84
Garden Soil	3.9	4.0	5.11	4.34

Table 4: Average soil pH of three methods for each soil sample

DISCUSSION

The optimum soil pH for paddy growth is between the range of 5.0-8.0. The pH of 5 different soil samples were tested its pH using 3 different methods, namely the universal indicator, soil pH meter and portable pH meter. By using 3 different methods, we are able to compare the readings recorded in three different methods to determine the accuracy and the average pH of each soil sample. As seen from the soil pH meter method, soil sample from the ODEC recorded the highest pH compared to other 4 soil samples which is 6.5. According to the plant observations made during week 2 of the paddy growth, ODEC soil has shown germination as a rapid rate compared to other soil samples. Other soil samples which showed seed germination were the garden soil and the soil from UMS peak. From table 1, the pH for garden soil was 3.9 whereas the pH of UMS peak was recorded 4.9, which was close to 5.0. As mentioned before, the pH range between 5.0-8.0 is suitable for paddy growth. However, this is not the necessary the case for every paddy plant as there are also many factors that affect seed germination such as water and nutrient availability, soil texture and also presence of organic matter. In the case of the pH of garden soil, the portable pH meter recorded a pH of 5.11 for garden soil and 4.0 pH using the universal indicator. As for the soil pH meter, the other two soil sample from B1 Residential College E and the compound of the Residential College E showed the pH of 4.6 and 3.6 respectively. The soil sample from both Blk B1 and compound of Residential College E did not show any seed germination. This may be explained through the low pH of both soil that makes it unsuitable for paddy growth. 

The pH taken using the universal indicator showed similar pH for each different soil samples compared to the soil pH meter method. As usual, the soil sample from ODEC showed the highest pH which was 7.0, UMS peak recorded a pH of 5.0 whereas the soil sample from Blk B1, Residential College E, compound and garden soil recorded a pH of 4.0 similarly. 

For the final method, using the portable pH method, the pH of each soil samples are shown in table 3. ODEC showed the highest pH of 7.37, pH of garden soil was 5.11, UMS peak was 5.71 and Blk B1 was 5.29. The soil sample from the compounds of Residential College E showed the lowest pH of all with a pH of 3.93.

Overall, the soil from ODEC proved to have the more suitable pH for paddy growth as each three method recorded pH of 6.5, 7.0 and 7.37 separately. As mentioned, a pH of 5.0-8.0 is more suitable for paddy growth. Hence the range is between slightly acidic to neutral or slightly above neutral soils. In this case, ODEC soil proved to be the most suitable compared to other soils. As soils become more and more acidic due to rainfall other factors, important nutrients such as phosphorus becomes less and less available to the plants and an increase in soil acidity will also increase the concentration of aluminium which is threatening to plants and this results in less yield and unsuitable environment for plant growth. The soil from UMS Peak and garden soil was also suitable for paddy growth as their soil pH ranges between 5.0-8.0. However, the average soil pH of three methods from the compounds of Residential College E was 3.84 which is significantly below the suitable pH range. Hence, the soil sample has not shown any seed germination thus far.

CONCLUSION

In conclusion, soil pH is indeed an important factor that greatly affects the germination rate and the growth of plants in the soil. To ensure healthy plant growth, ensure that before utilizing the soil, perform various soil analysis test to determine the suitability of the soil for plant growth. Hence in this case, the pH for suitable paddy growth ranges between 5.0-8.0.

REFERENCES

1) Cornell University Agronomy Fact Sheet #5- Soil pH for Field Crops. Retrieved from http://cceonondaga.org/resources/soil-ph-for-field-crops

2) The Mosaic Company. 2016. Soil pH. Retrieved from http://www.cropnutrition.com/efu-soil-pH

3) Bolland, M., Gazey, C., Miller, A., Gartner, D., and Roche, J. (2004). Subsurface Acidity. Department of Agriculture and Food, Western Australia Bulletin 4602.

SOIL WATER HOLDING CAPACITY ANALYSIS

INTRODUCTION

     Soil water holding capacity is the amount of water that a given soil can hold for crop use. Soil water holding capacity is controlled primarily by the soil texture and soil organic matter. Soil texture is a reflection of the particle size distribution of a soil. In general, the higher the percentage of silt and clay sized particles, the higher the water holding capacity. The small particles (clay and silt) have a much larger surface area than the larger sand particles. The larger the surface area. the easier for the soil to hold a greater quantity of water. The water holding capacity also can be influenced by the amount of organic matter. The higher the level of organic matter in a soil, the larger the water holding capacity also, due to the affinity of organic matter for water. Soil organic water has a natural magnetism to water and they can be increased by the adding plant or animal material.

     A soil with a higher water holding capacity (i.e. a clay loam) reaches the saturation point much slower than a soil with a limited water holding capacity (i.e. a sandy loam). 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 after a soil is saturated with water.

OBJECTIVES

-To determine the soil water holding capacity for each soil.

MATERIALS AND APPARATUS

1.     Filter paper

2.     Tin can

3.     5 soil samples

4.     Small plastic rods

5.     Electronic balance

6.     Plastic container

7.     Water

PROCEDURES

1.     A filter paper was taken and placed at the bottom of the tin box.

2.     The tin was weighed along with the filter paper.

3.     A certain volume of soil was taken and transferred into the tin box, and it was ensured that the volume of all the 5 sample soils in the tin box was similar.

4.     The soil sample was tested.

5.     The soil was pressed gently until a uniform layer on top.

6.     The tin box was weighed with soil and its weight was recorded.

7.     Water was poured into the weight plastic container and two small plastic rod were put to support the tin box floating in contact with water.

8.     The tin box was left undisturbed until the water surface on top of the soil was moist.

9.     The tin box was then lifted, and the dripping water was wipe from the tin box bottom. The weight was then measured.

RESULTS

Soil Water Holding Capacity

Soil Sample	Weight of tin + Filter paper (A)	Weight of tin + Filter paper + Soil sample (B)	Weight of tin + Filter paper + Wet soil (D)	Weight of dry soil B - A = C	Weight of wet soil D – A = E	Mass of water absorbed by soil E – C = N	% of water holding capacity
ODEC	9.60 g	168.47 g	193.78 g	158.87 g	184.18 g	25.31 g	13.74%
Garden Soil	9.88 g	92.41 g	146.95 g	82.53 g	137.07 g	54.54 g	39.79%
UMS Peak	9.55 g	112.26 g	158.40 g	102.71 g	148.85 g	46.14 g	31.00%
KG E	9.54 g	124.24 g	145.20 g	114.70 g	135.66 g	20.96 g	15.45%
BLK B1	9.82 g	105.90 g	156.60 g	96.08 g	146.78 g	50.70 g	34.54%

Formula of the percentage of water capacity:

N/E x 100

N = mass water absorbed by soil

E = Weight of wet soil

DISCUSSION

Soil water holding capacity

    Soil perform many vital functions in order to sustain lives and one of it is to store moisture and providing water supply to plants between rainfalls or irrigations. Various environmental process such as evaporation from the soil surface, transpiration by plants and as well as deep percolation combine to reduce the supply of water in the soil. Hence, if the soil moisture becomes too low, plants may be water and nutrients stressed. Hence, soil plays a vital roles as buffer which determines the fate of a plant against dry spells.     

      During the experiment, there were a few types of soil samples that have been taken for analysis which are soils from ODEC, garden soils, soils from UMS Peak, soils from the compounds of residential college E and soils from Residential College E, Blk. B1. 

     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 (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 or magnetism of organic matter for water. Poor structure, low organic matter, low carbonate content and presence of stones all reduce the moisture storage capacity of a given texture class. Clays can store large amount of water whereas sandy soil has low percentage of soil holding capacity.

     From the soil texture analysis through the texture by feel method, ball and ribbon method, we were able to interpret the soil texture of 5 of our soil samples. Soil sample from ODEC shows sandy soil texture, soil from UMS Peak showed sandy loam texture, garden soil showed loam or sandy loam texture, soils from the compounds of KG.E showed loamy sand texture and lastly soils from Blk B1 showed loam texture. Based on these textures, we were able to roughly interpret the ability of each soil’s water holding capacity. 

     Based on the experiment conducted, the Garden Soil is known to have the highest percentage of water holding capacity which is 39.79 %. The soil that has the second highest percentage of water holding capacity is soil from Blk B1 which is 34.54%. The Garden Soil and the soils from Blk B1 in this case are categorized as soil with the highest water holding capacity despite their texture being loam or sandy loam as these 2 soils are being compared with 3 other soils that has more sand composition and possibly lesser organic material which affects the soil water holding capacity. Soils with smaller particles (silt and clay) have a larger surface area than those with larger sand particles, and a large surface area 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 amount of organic matter in soil also affects how much water the soil is able to retain. This is because organic matter has a natural attraction to water. So, the more organic matter a soil contains, the greater the affinity it has with water. Clay soil is very rich in organic matter. Because clay soil retains a lot of water and is high in organic matter, it can be damaged easily when cultivated while wet. Clay soil is also harder to cultivate than other soil types because it is naturally denser. Because the particles in clay soil swell and shrink as the soil becomes wet and then dries, clay soil can cultivate itself.

     Based on the analysis conducted, the soil that has lowest percentage of water holding capacity are soil samples from ODEC being the lowest and soil samples from the compounds of residential college E being the second lowest. ODEC soil sample recorded percentage of 13.74% whereas soil of the KG. E compound records a 15.45%. The soil samples from ODEC are categorized sandy. It is only normal that the samples taken from a sandy beach shows such percentage as their texture are mainly composed of sand whether its fine or coarse sand. Sand with its larger particles, low nutritional content, low organic matter content and good drainage, retains the least amount of water, although it is easily replenished with water. The more organic matter a soil contains, the greater the affinity it has with water. Clay soil is very rich in organic matter while sandy soil has very little. In turn, sandy soil is simple to work, and loam soil is moderately difficult to work. Although nutritionally poor, sandy soil is well-suited for some kinds of plants. In turn, the heaviness of clay soils makes it less than ideal for some plants, despite clay's high nutrition content.

     From the test conducted, the soils that have moderate percentage of water holding capacity among the 5 sample soils are soil samples from UMS peak which recorded a percentage of 31.00%. The amount of organic matter in soil also affects how much water the soil is able to retain. Silt and loam have a moderate amount of organic matter and can be amended with compost to have more. Loam and silt are rich nutritionally and easier to work than clay soil, and loam's and silt's particles are not damaged when the soils are worked while wet. Loam soil is considered ideal for a wide variety of plants as a consequence of its rich nutritional content and ability to retain moisture while resisting becoming waterlogged at which it drains well. 

CONCLUSION

     In conclusion, the property of the soil being able to hold water is important as it impacts on my aspects such as the productivity of the soil, the abundance of living organisms living in the soil, the type of vegetation and also the fertility of the soil. Different soil texture with different soil mineral composition results in different ability to hold water. As we can conclude, sandy soils are unable to hold water as efficient as soils which are mostly composed of clay and silt.

REFERENCE

1) Agvise Laboratories. (no date). Water Holding Capacity. Retrieved from https://www.agvise.com/educational-articles/water-holding-capacity/

2)  Curell, C. 2011. Why is soil water holding capacity important? Retrieved from http://msue.anr.msu.edu/news/why_is_soil_water_holding_capacity_important. Michigan State University Extension

3) Yu, OY., Raichle, B. & Sink, S. Int J Energy Enviro Eng ( 2003 ) 4: 44. https://doi.org/10.1186/2251-6832-4-44

4)   Karhu K, Mattila T, Bergström I, Regina K: Biochar addition to agricultural soil increased CH4 uptake and water holding capacity - results from a short-term pilot field study. Agr Ecosyst Environ 2011, 140(1):309–313.

5)  Oregon State University- Soil Characteristic-Water Holding Capacity. Retrieved on 27/3/2018 : http://forages.oregonstate.edu/ssis/soils/characteristics/water-holding-capacity

SOIL MOISTURE ANALYSIS

INTRODUCTION

     Water contained in soil is called soil moisture. The water is held within the soil pores. Soil water is the major component of the soil in relation to plant growth. If the moisture content of a soil is optimum for plant growth, plants can readily absorb soil water. Not all the water, held in soil, is available to plants. Much of water remains in the soil as a thin film. Soil water dissolves salts and makes up the soil solution, which is important as medium for supply of nutrients to growing plants. The soils hold water (moisture) due to their colloidal properties and aggregation qualities. The water is held on the surface of the colloids and other particles and in the pores. The forces responsible for retention of water in the soil after the drainage has stopped are due to surface tension and surface attraction and are called surface moisture tension. This refers to the energy concept in moisture retention relationships. The force with which water is held is also termed as suction.

OBJECTIVES

-To identify the soil moisture of each sample soil using 2 different methods

-To understand the vital role of soil moisture

-To identify the factors that affect soil moisture in different soil moisture

MATERIALS AND APPARATUS

Oven Method:  

1) 5 different soil types

2) 5 aluminium foil containers

3) Lab Oven

4) Analytical Balance

Moisture Tester Censor Method:

1) Moisture Tester Sensor

2) 5 different soil types

3) Cloth

4) Water

PROCEDURE

1.     The soil moisture of the plant soil was checked before the plant was watered using the moisture tester censor tool.

2.     The tool was then washed to remove soil remnants before testing a different soil type.

3.     Step 1 and 2 were then repeated on 4 other soils

4.     A sample soil type was placed in an aluminium foil container to be air dried for a week.

5.     The air-dried soil were then weighed using an analytical balance before placing the air dried soil into an oven

6.     The air-dried soil was then placed in an oven to be heated for 1 hour at the temperature between 70-80 degree celcius.

7.     After an hour, the soil sample was removed from the oven and weighed its weight again.

8.     Step 4 until 7 were then repeated on 4 other soil types.

9.     Data were then recorded to determine the soil moisture of each soil. 

     

    RESULTS

    Table 1 : SOIL MOISTURE THAT WERE AIR DRIED FOR A WEEK

Types of Soils	Weight of tray (W1)	Weight of Tray + Soil (W2)	Weight of tray + Soil after drying (W3)	Moisture Content (%) [(W2-W3)/(W3-W1)] x 100
Residential College E, Blk B1	5.797	92.700	85.203	9.44
Residential College E Compound	5.797	100.400	92.200	9.49
ODEC	5.797	98.200	92.103	7.06
UMS Peak	5.797	86.400	78.603	10.71
Garden Soil	5.797	87.200	79.303	10.74

Table 2: RESULT FOR SOIL MOISTURE USING MOISTURE TESTER SENSOR

Types of Soils	Moisture Content
Residential College E, Blk B1	7.5
Residential College E Compound	4.73
ODEC	2.50
UMS Peak	6.50
Garden Soil	5.67

DISCUSSION

      Soil moisture is an important soil property that is greatly affected by numerous factors. Soil moisture as mentioned in the introduction, is the amount of water retained in the pore spaces of soil. Generally, 50% of the volume of soil are pore spaces where these spaces are mainly occupied by air and water. Ideally, 25% would be air and the other 25% of the total pore spaces would be occupied by water. Water plays an important role in soil, same goes to the importance of soil moisture. Soil moisture provides water for various biochemical reactions, supporting various types of living organisms and vegetations and also contribute to the continual chemical weathering of parent materials in the soil. Hence, soil moisture or the water retained in soil is greatly important.

      However, soil moisture can be affected by certain factors such as soil texture, presence and concentration of organic and mineral materials and also the living organisms in the soil. Generally, soil dominated by sand particles which are large in size particles. A saturated coarse, sandy soil is not able to hold a large amount of water compared to a soil saturated with heavily silted clay. Sand are large size particles that take up a lot of physical space and sand particles do not have high affinity to bind with water. Hence, a lot of water will drain out as it passes the sandy soil texture due to gravity and before field capacity is reached.

As we can see from the recorded in the above results, through air drying the soils and a several extra steps, we were able to show that ODEC which has the sandy soil texture has the lowest soil moisture percentage, 7.06% compared to other soil types, followed by soils from Blk B1, which was 9.44%. Soils from the compound of Residential College E recorded a soil moisture content of 9.49%. The next two highest soil moisture soils are from UMS Peak and garden soil, where both soil recorded a soil moisture of 10.71% and 10.74% respectively. It can be seen that UMS Peak and Garden Soil both have the highest percentage of soil moisture compared to soil from ODEC. The soil texture of garden soil and Blk B1 were interpreted as loam texture where it has an intermediate texture between clays and sandy soils. The presence of clay and silt in this texture allows it to bind to water molecules due to it large surface area exposed for water binding and also the fine particle sizes of silt and clay makes it easy for this soil texture to trap and retain water. Soils of UMS peak and compounds of Residential College E are sandy loam and loamy sand respectively. UMS peak with its texture being sandy loam consists enough clay to retain certain amount of water compared ODEC soils that is mainly dominated by sand. Hence, compared to ODEC soils, compounds of Residential College E, compound soil (loamy sand texture), the water retention ability of UMS peak soil is better.

      For the moisture tester sensor, the readings were recorded where ODEC soils have the 

least soil moisture whereas soil from garden soil and Blk B1 recorded the two highest soil moistures. Due to the constant exposure to rainfall and also watering, the readings in the moisture tester sensor that were taken directly from the planting pots may show a slight changes or differences. 

CONCLUSION

In conclusion, these different soil textures of different soil samples shows different soil moisture content. Two methods were carried out to determine the soil moisture of each soil sample. This is to ensure that the readings and data recorded can be proved accurate. Generally, soil that has large particle sizes, low organic matter, low clay and silt component and poor aeration may result in low soil moisture. It can be concluded that, soil samples from the garden soil and Blk B1 which are loam texture has the two highest soil moisture due to their reasonable amount of clay and silt found as compared to other sandy soils.  

 REFERENCES

1) H.J.S. Finch, A.M. Samuel, G.P.F. Lane. 2014. Soils and soil management. Lockhart & Wiseman’s Crop Husbandry Including Grassland (Ninth Edition). https://doi.org/10.1533/9781782423928.1.37

2) Measurement Engineering Australia- Soil Moisture Content in the Field. Retrieved on 27/3/2018 : http://mea.com.au/soil-plants-climate/soil-moisture-monitoring/learning-centre/soil-moisture-content-in-the-field