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CHAPTER 1

INTRODUCTION

Plants require at least 16 elements for normal growth and for completion of their

life cycle. Those used in the largest amounts, carbon, hydrogen and oxygen, are non-

mineral elements supplied by air and water. The other 13 elements are taken up by

plants only in mineral form from the soil or must be added as fertilizers. Plants need

relatively large amounts of nitrogen, phosphorus, and potassium. These nutrients are

referred to asPrimary nutrients, and are the ones most frequently supplied to plants in

fertilizers. The three secondary elements, calcium, magnesium, and sulphur, are

required in smaller amounts than the primary nutrients. Calcium and magnesium are

usually supplied with liming materials, and sulphur with fertilizer materials.

Contaminants in rainfall also supply10 to 20 pounds of nitrogen and sulphur per acre

each year, depending on local air quality.

The micronutrients consist of seven essential elements: boron, copper, chlorine,

iron, manganese, molybdenum, and zinc. These elements occur in very small amounts

in both soils and plants, but their role is equally as important as the primary or

secondary nutrients. A deficiency of one or more of the micronutrients can lead to

severe do not contain sufficient amounts of these nutrients to meet the plant's

requirements for rapid growth and good production. In such cases, supplemental

micronutrient applications in the form of commercial fertilizers or foliar sprays must

be made. Thus the soil supplies 13 of the 15 elements required for nutrition of higher

plants. These elements must be available , continuously, and in balanced proportions

to support photosynthesis and other metabolic processes of plants.

If most of the essential elements is missing, plant productivity will be limited, or

the plant may cease to grow entirely. The principle of limiting factors, which states

that the level of production can be no greater than that allowed by the most limiting of

the essential plant growth factors, applies in both cropping systems and in natural

ecosystem.

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CHAPTER 2

SOIL FERTILITY

Essential elements can occur in one or more of three physical forms: solid, liquid or

gas. We tend to deal primarily with solid and liquid forms of the elements in soils, but

the non-mineral elements as well as nitrogen and sulphur can also occur in gaseous

forms underCertain soil conditions. The chemical form of an element strongly

influences how a nutrient reacts with other elements and compounds found in the soil.

The nutrient elements can each occur in several forms, but we need to consider those

which commonly occur in the soil .

Soil organic matter contains large amounts of carbon, which results in many complex

types of structures and chemical properties. But basically, organic matter reacts in the

soil like a tiny, spongy solid with a large amount of negative charge. Many of its

complexstructures also react strongly with smaller organic molecules, such as

pesticides and root exudates.

Soil nitrogen is the most difficult nutrient to characterize: it occurs in organic and

inorganic forms, in solution and as a gas, and as cation and an anion. Plant roots

absorb only the inorganic forms. Common forms of N contained in fertilizers and

fresh manuresinclude ammonia, urea, ammonium and nitrate.

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CHAPTER 3

EFFECTS ON CROPS

Nitrogen (N) is an essential nutrient used in relatively large amounts by all living

things. It is critically important to plants because it is a fundamental part of the

chlorophyll molecule and is essential in the formation of amino acids and proteins.

Plants obtain their N as inorganic nitrate and ammonium ions in the soil solution but

N is not a natural constituent of rocks or minerals.

Although phosphorus is required in lower amounts than other major nutrients, it is

critical in the early developmental stages of growth, and in energy transfer within the

plant throughout the growing season.. Typical phosphorus contents of plants range

between 0.1 to 0.46 percent P on a dry weight basis, approximately ten times less than

for nitrogen or potassium. Phosphorus apparently stimulates young root development

and earlier fruiting (earliness). It is essential in several biochemical that control

photosynthesis, respiration, cell division, and many other plant growth and

development processes. Phosphorus is concentrated in the seed and fruit, and strongly

affects seed formation.

Potassium is required by plants in approximately the same or slightly larger amounts

as nitrogen. Uptake of K occurs in the K+ form. Most of the functions of K in the

plant are indirect in that K is necessary for other chemical reactions to operate

properly. Some 60enzymes require the presence of K, with high concentrations of K

found in the active growing points and immature seeds. Potassium forms no organic

compounds within the plant, but remains in the ionic K+ form. The plant uses K in

photosynthesis, in carbohydrate transport, in water regulation, and in protein

synthesis. The benefits of proper K nutrition include improved disease resistance,

vigorous vegetative growth, increased drought tolerance, improved winter hardiness

of forages, and decreasedlodging. As a result, potassium fertilization is frequently

associated with improved crop quality as well as better handling and storage

properties.

Micronutrients are defined as those elements required in small quantities for higher

plant growth and reproduction. The exact quantity needed varies with plant species

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and the specific element. Seven elements are generally considered as plant

micronutrients, these include boron (B), Copper (Cu), chlorine (Cl), iron (Fe),

manganese (Mn), molybdenum(Mo), and zinc (Zn). To better understand the relative

amount of these elements needed by plants, we can look at the plant removal rate of a

crop like corn.

TYPES OF FERTILIZERS

Chemical Fertilizers

In dealing with soils low in nutrients, we must consider what the difference is

between organic and synthetic chemical fertilizers. The latter are used to feed the

plant directly; therefore the ingredients have to become available rapidly, which

means that a spring application has to produce a satisfactory crop during that growing

season. Except for phosphorous, any left-over nutrients will mostly have leached out

by the following spring and in doing so may pollute the

groundwater. Although certain bacteria are needed for the breakdown of some

chemical fertilizers, the balanced activity of soil organisms in releasing nutrients from

natural sources is not needed in the chemical program. It has been reported that

chemical fertilizers actually suppress microbial life in the soil.

Organic Fertilizers

Organic fertilizers, on the other hand, have low solubility; to release their nutrients

and for further decomposition they depend on micro-organisms and weak acids from

organic matter. They activate microbial life instead of suppressing it. Nutrients

become available when needed and there is little or no leaching. This means that

most organic fertilizers work more slowly, exceptblood meal and, to some extent bone

meal. It is a matter of long-term fertility rather than creating instant fertility. This

explains why it is good practice to mix these slow acting fertilizers in the compost

pile to start bacteria working on them. The bio-dynamic method stresses the

importance of a natural balance of soil life; if disturbed by chemicals, other

undesirable organisms may increase and fill the gap. It is claimed that this not only

pertains to bacteria but also to other important soil organisms like fungi, nematodes,

beetles, springtails and larvae. Organic matter, although so important in the life of the

soil, is not usually very rich in nutrients by itself unless organic fertilizers have been

added, and beginners in particular may need these to bring their soil to full fertility,

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which can then be maintained by compost and such organic amendments as are

necessary.

ADVANTAGES OF FERTILISERS

Descriptions and Uses of Available Organic Fertilizers

Note: Certified organic growers should check their certifying body guidelines before

usingorganic fertilizers.

Blood Meal - works rather quickly and is an excellent source of nitrogen for the

garden.

Bone Meal - releases its phosphorous faster than rock phosphate. It is relatively

expensive and more suited for garden use than for farm use.

Wood Ashes - hardwood preferably for most soils. Can not be purchased. Keep dry

before application to stop potash from leaching out.

Kelp - is derived from seaweed and, in addition to being rich in potash, has several

other beneficial properties. It promotes the release of locked-up minerals and it

contains hormones which enhance growth and have been reported to increase

resistance to insects, diseases and light frost.

Liquid Fish Fertilizers - are good for side dressing during the summer if plant

growth is not satisfactory and for container-grown plants. Dilute according to the

directions. They contain trace elements and work fairly fast.

Hard and Soft Rock Phosphates - do not move or dissolve in the soil, hence they

have to be worked in. The phosphorous becomes available after it has been acted

upon by micro-organisms; therefore, combine it with compost, manure or green

manure, especially clovers. Do not apply lime at the same time. If the soil is acid, soft

rock phosphate is preferred. Excess phosphate does not harm the plants or leach out. It

is stored in the soil until needed by plants in later years. Wear a dust mask or

respirator for handling rock phosphate.

Granite Dust and Greensand - are an excellent source of potash which becomes

available slowly. Greensand marl has a high moisture-holding capacity and is rich in

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trace elements due to its origin in the sea. It is difficult to find a source of supply.

Feed stores, garden centres, nurseries or even hardware stores may be able to get it for

you.

Worm Castings - boost the activity of soil life and improve structure.

Manure - from livestock and poultry varies widely in N, P and K content depending

on the kind of animal and its feed; also on the storage method, period of aging,

moisture content and the amount of incorporated bedding (straw, etc.). If improperly

handled, most of the ingredients may be lost by leaching and volatilization. Manure

contains high amounts of bacteria and organic matter and activates soil life. Dried

poultry and livestock manure (ideally from organic farms) is sold in bags with a

guaranteed analysis of N, P andK and is much easier to handle than raw manure.

Compost -made correctly by aerobic methods with good organic residues in sufficient

quantity, with the right carbon/nitrogen (C/N) proportions is valuable. It will break

down to an ideal C/N ratio with a high concentration of minerals. The effect of

compost is cumulative and too much should not be expected from it at once.

Various commercial granular organic fertilizer mixtures suitable for general use

are on the market. They can be applied with applicator equipment, such as lawn

spreaders.

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CHAPTER 4

RASPBERRY PI MICROCONTROLLER

INTRODUCTION AND FEATURES

The Raspberry Pi is a series of credit card- sized single board computers developed in

the United Kingdom by the Raspberry Pi Foundation with the intent to promote the

teaching of basic computer science in schools and developing countries. The original

Pi and Pi 2 are manufactured in several board configurations through licensed

manufacturing agreements with Newark Element 14, RS Components and Ego man.

The hardware is same across all manufacturers.

Several generations of Pi has been released. All models feature a Broadcom system on

chip which include an ARM compatible CPU and an on chip graphic processor unit

GPU. CPU speed range is from 700 Mhz to 1.2 Ghz for pi 3 and on board memory

range from 256 MB to 1 GB RAM secure digital SD cards are used to store the

operating system and program memory in either the SDHC or Micro SDHC sizes.

Most boards have between one and four USB slots, HDMI and composite video

output, and a 3.5 mm phono jack for audio. Lower level output is provided by a

number of GPIO pins which support common protocols like I2C. Some models have

an RJ45 Ethernet port and the Pi 3 has on board Wi-Fi 802.11n and Bluetooth.

The Foundation provides Debian and Arch Linux ARM distributions for download,

and promotes Python as the main programming language, with support for BBC

BASIC C,C++, Java, Perl, Ruby, Squeak Smalltalk and more also available.

The system on a chip (SoC) used in the first generation Raspberry Pi is somewhat

equivalent to the chip used in older smartphones. The Raspberry Pi is based on the

Broadcom BCM2835 SoC, which includes an 700 MHz ARM1176JZF-S processor,

Video Core IV graphics processing unit (GPU), and RAM. It has a Level 1 cache of

16 KB and a Level 2 cache of 128 KB. The Level 2 cache is used primarily by the

GPU. The SoC is stacked underneath the RAM chip, so only its edge is visible.

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ARCHITECTURE AND PIN DIAGRAM

● Two Models A& B, priced at $25 and $35Respectively

● Model A/B:

○ Broadcom BCM2835 (CPU & GPU)

○ 256/512MB SDRAM

○ 1/2 USB 2.0 Ports

○ None/Ethernet Port

○ HDMI

○ Audio

○ SD Card Slot

○ Micro USB for power

● ARM11J6JZF-S (ARM11 Family)

● ARMv6 Architecture

● Single Core

● 32-Bit RISC

● 700 MHz Clock Rate

● 8 Pipeline Stages

● Branch Prediction

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BLOCK DIAGRAM

Fig 4.1- ARMv6 Architecture

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PIPELINE STAGES USED BY RASPBERRY PI

Fig 4.2-Pipelie stages used by Raspberry Pi

PIN DIAGRAM

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Fig 4.3-Pin Diagram Raspberry Pi

● Core

● Load Store Unit

● Pre fetch Unit

● Memory System

● Level On

● Interrupt Handling

● System Control

● AMBA Interface

● Coprocessor Interface

● Debug

● Instruction cycle summary and interlocks

● Vector Floating-Pointe Mem. System

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APPLICATIONS AND USES

● Robotics

● Game emulation

● Media Servers

● Education (Python is the primary language used)

● Powerful enough to be used as a personal computer

● Thousands of other projects (Often used in Senior Design)

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CHAPTER 5

SOIL TEMPERATURE MEASUREMENT USING

TEMPERATURE SENSOR

Base Station Options

1. Raspberry Pi

- System-on-a-chip device that functions as an open source computing device

- Inexpensive and flexible

2. Existing Computer Station

-Pre-existing computer station located at elementary school

- No additional cost, but increased risk due to not having access to station during

design phase.

3. Temperature sensor

- Easily measures the temperature of soil and notes the rate of soil fertility loss due to

increased temperature.

Structure/Enclosure Options

1. Waterproof Enclosure with Modular Components

- Provide safe housing for electrical components

- Most flexible

2. Waterproof Enclosure with Hard-Wired Components

- Also provides safe housing for electrical components

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- More stability, but less flexibility

PROPOSED DESIGN SOLUTION

Fig 5.1-Crop Sensor Network Diagram(a)

Fig 5.1-Crop Sensor Network Diagram(b)

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COORDINATING THE TESTER USING WIRELESS

COMMUNICATION DEVICES LIKE ZIGBEE.

Fig 5.2-Coordination Setup Using Zigbee

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Fig 5.3-Raspberry Pi Micro

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CHAPTER 6

SOIL NITROGEN TESTING USING ELECTRODES

The nitrogen content is very essential in determining the soil fertility content. This is

measured by two electrodes namely anode and cathode which measures the current

flowing through the soil. The two electrodes carries the charged ions which develops

the electric current.

This current is measured and depending upon the rate of flow the intensity of the LED

bulb is gradually changed. The LED glows with highest efficiency when the the

current flowing though the circuit is above the buffer value and it glows at the lowest

intensity when no or very few amperes of current flow through the electrodes.

A potentiometer is also provided to change the values of the current passing through

the electrodes and thus on varying the resistance the voltage also chabges which

further affects the intensity of the LED.

The elctrodes measuring the current thus measures the negative ions or anions of the

nitrogen present in the soil and thus determines the reduced or the increased content

of nitrogen in the soil thus verifying that nitrogen content in the soil affects the soil

fertility.

It uses the principle of ohm law as:- voltage is current times resistance.

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ALGORITHM AND CALCULATIONS

The device uses the python programming language to access the function. It uses a

simple subtraction program with one fixed value and the other value is a variable

which is a measured temperature value of the soil using the temperature sensor.

The basic steps are as follows:-

1 Initiate the program with two variables

2 Give the appropriate string operand for measuring value from a temperature

sensor.

3 Define one value as a constant room temperature.

4 Define the other variable as the measured temperature.

5 Perform a subtraction among these values.

6 Give a checking condition such that if the output of difference operation is

greater than 5 degree Celsius the LED glows indicating loss of soil fertility.

7 If not the LED doesn’t glow indicating the soil fertility is intact apt for the

crops in mind, in this case its corn.

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The sample program is given as

import time

importRPi.GPIO as GPIO ## Import GPIO library

GPIO.setmode(GPIO.BOARD)

GPIO.setup(11, GPIO.OUT) ## GPIO Pin 11 is output

float senseout,roomout

float n=abs(roomout-senseout)

if(n>=5)

GPIO.output(11,True) ##led on

time.sleep(5)

GPIO.output(11,False) #led off after 5 seconds

else

print("something will happen")

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CONCLUSION

Thus we have successfully developed the soil fertility tester using a raspberry pi

which reduces physical hassles and also reduces cost. Thus making this device cheap,

affordable and scientifically potent for further research projects and advancements.

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REFERENCES

[1].National Bureau of Statistics of China, China Statistical Yearbook 2006, Beijing

China, 2006.

[2]. Minzan Li. "Soil Parameters Sensing for Precision Farming": [Ph.D.

Dissertation].Tokyo: Tokyo University of Agriculture and Technology, 2000.

[3]. Missouri Agricultural Experimental Station, Recommended chemical soil test

procedures, Columbia, US: North Central Regional Research Publication, University

of Missouri, 1998.

[4]. J. Ruzicka, E.H Hansen. and E.A. Zagatto, "Flow injection analysis. Part II: use

of ion-selective electrodes for rapid analysis of soil extracts and blood serum.

Determination of potassium sodium and nitrate", Analytica Chimica Acta, Vol. 88,

no. 1, pp. 1-16, 1977.

[CrossRef]

[5] C. Hongbo, E.H. Hansen and J. Ruzicka, "Evaluation of critical parameters for

measurement of pH by flow injection analysis", Analytica Chimica Acta, Vol. 169,

pp. 209-220, 1985.

[CrossRef]

[6]. F. AMR, L. JLC, and R. AOSS, "Potentiometric determination of total nitrogen in

soils by flow injection analysis with a gas-diffusion unit", Australian Journal of Soil

Research, Vol. 34, pp. 503, 1996.

[CrossRef]

[7].H.J. Kim, J.W. Hummel, and S.J. Birrell, "Evaluation of ion-selective membranes

for realtime soil nutrient sensing", Transactions of the ASAE, Vol. 46, no. 3, pp.

1075-1086, 2003.

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