evaluation of air pollution tolerance index of bougainvillea, santan and mahogany

CHAPTER 1

INTRODUCTION

A. Background of the Study

Air pollution tolerance index (APTI) is used to determine plant species that are

tolerant to air pollution (Agbaire, 2009 as cited by Seyyednjad and others, 2011). The

plant species with APTI value that is less than 16 is considered sensitive and act as a

bioindicator of air pollution; APTI value that ranges from 17 to 29 is considered

intermediate and greater than 30 is tolerant to air pollution (Liu and Ding, 2008). The

response of plants to air pollution at physiological and biochemical levels can be

understood by analyzing the factors determining resistance and susceptibility. Studies

show that air pollution has an impact on the ascorbic acid content, total chlorophyll

content, leaf extract pH, and relative leaf water content of plants. For the reason that a

single parameter may not provide a clear picture of pollution-induced changes, air

pollution tolerance index (APTI) based on all four parameters has been used to identify

the tolerance levels of plant species (Liu and Ding, 2008). Sensitivity and response of

plants to air pollutants is variable. Using plants as an indicator of air pollution, is the

possibility of synergistic action of pollutants (Lakshmi and others, 2009 as cited by

Seyyednjad and others, 2011).

Several contributors agree that air pollution affects plant growth adeversely (Rao,

2006 as cited by Seyyednjad and others, 2011). In spite of the adverse affections of these

pollutants, there are still plants that are tolerant to air pollution (Nivane and others, 2001

as cited by Seyyednjad and others, 2011). Plants play an important role in monitoring and

maintaining ecological balance by actively participating in the cycling of nutrients and

gases (Seyyednjad and others, 2011). Also, plants are an integral basis for all ecosystems

and most likely to be affected by airborne pollution which are identified as the organisms

with most potential to receive impacts from ambient air pollution. Also, the effects are

most often apparent on the leaves which are usually the most abundant and most obvious

primary receptors of large number of air pollutants. Biomonitoring of plants is an

important tool to evaluate the impact of air pollution (Jyothi and Jaya, 2010).

1

Air pollution is a major problem arising mainly from industrialization (Odilara

and others, 2006 as cited by Seyyednjad and others, 2011). Air pollution is the human

introduction into the atmosphere of chemicals, particulate matter, or biological materials

that cause harm or discomfort to humans and other living organism, or cause damage to

the environment. Pollutants could be classified as either primary or secondary. Pollutants

that are pumped into the atmosphere and directly pollute the air are primary pollutants

while those that are formed in the air when primary pollutants react or interact are known

as secondary pollutants (Agbaire and Esiefarienrhe, 2009 as cited by Seyyednjad and

others, 2011).

Iloilo City has been industrializing for years; the populations in the area and the

number of vehicles have been increasing, and new factories and commercial

establishments were built. As an effect, the air around this area becomes more and more

polluted. This study aimed to determine the air pollution tolerance index of three plant

species (Ixora coccinea, Swietenia macrophylla, and Bougainvillea spectabilis)

commonly found in the polluted and unpolluted areas of Iloilo City.

B. Statement of the Problem

Which among the three plant species (Ixora coccinea, Swietenia macrophylla, and

Bougainvillea spectabilis) that are commonly found in the polluted and unpolluted areas

of Iloilo City can be used as a bioindicator for air pollution?

C. Objectives

General objective:

To determine the air pollution tolerance index of three plant species (Ixora

coccinea, Swietenia macrophylla, Bougainvillea spectabilis) commonly found

in polluted and unpolluted areas of Iloilo City.

Specific Objectives:

To determine and calculate the relative leaf water content (RWC) of the three

plant species (Ixora coccinea, Swietenia macrophylla, Bougainvillea

2

spectabilis) that are commonly found in the polluted and unpolluted areas of

Iloilo City.

To determine and calculate the total chlorophyll content (T) of the three plant

species (Ixora coccinea, Swietenia macrophylla, Bougainvillea spectabilis)

that are commonly found in the polluted and unpolluted areas of Iloilo City.

To determine and calculate the leaf extract pH of the three plant species (Ixora

coccinea, Swietenia macrophylla, and Bougainvillea spectabilis) that are

commonly found in the polluted and unpolluted areas of Iloilo City.

To determine and calculate the ascorbic acid (AA) content of the three plant

species (Ixora coccinea, Swietenia macrophylla, Bougainvillea spectabilis)

that are commonly found in the polluted and unpolluted areas of Iloilo City.

D. Significance of the Study

Air pollution is a major problem arising mainly from industrialization. Iloilo City

has been industrializing for years and the air around this area becomes more and more

polluted and; air pollution causes harm and discomfort to humans, to other living

organisms and to the environment.

Plants play an important role in monitoring and maintaining ecological balance by

actively participating in the cycling of nutrients and gases (Seyyednjad and others, 2011).

Also, plants are an integral basis for all ecosystems and most likely to be affected by

airborne pollution which are identified as the organisms with most potential to receive

impacts from ambient air pollution. Also, the effects are most often apparent on the

leaves which are usually the most abundant and most obvious primary receptors of large

number of air pollutants. Biomonitoring of plants is an important tool to evaluate the

impact of air pollution (Jyothi and Jaya, 2010). Studies show that air pollution has an

impact on the ascorbic acid content, chlorophyll content, leaf extract pH, and relative

water content of plants. For the reason that single parameter may not provide a clear

picture of pollution-induced changes, air pollution tolerance index (APTI) based on all

3

four parameters has been used to identify the tolerance levels of plant species (Liu and

Ding, 2008).

E. Scope and Delimitation

This study focuses on the air pollution tolerance index of three plant species

(Ixora coccinea, Swietenia macrophylla, Bougainvillea spectabilis) commonly found in

the polluted and unpolluted areas of Iloilo City. The relative leaf water content (RWC),

total chlorophyll content (T), leaf extract pH, and ascorbic acid (AA) content will be

determined to calculate the air pollution tolerance index of the five species of plants.

F. Definition of Terms

Santan (Ixora coccinea)

Santan is an erect and smooth ornamental shrub, growing to a height of 2 to 3

meters. Leaves are stalk less or on very short stalks, oblong, 5 to 9 centimeters long,

heart-shaped or rounded at the base and blunt-tipped. Flowers are many, pink or red, and

borne in terminal, stalk less or shortly stalked hairy cymes. Calyx teeth are short and

pointed. Corolla-tube is slender, 2.5 centimeters long; lobes are spreading and oblong,

about half the length of the tube. Fruit is reddish, almost round, about 5 millimeters in

diameter.

In this study, santan is a test organism taken from the polluted areas of Iloilo City.

The air pollution tolerance index of santan was calculated to determine if it is sensitive to

air pollution.

Mahogany (Swietenia macrophylla)

Mahogany is a deciduous, erect tree growing to a height of 10 meters, with a

heavy, dark-green, and dense crown. The trunk is more or less buttressed. Bark is dark

gray and ridged. Young leaves when in the flush are pink, soon turning green. Leaves are

alternate, smooth, compound, about 15 centimeters long, in 3 to 6 pairs, most often 5

pairs, of leaflets. Leaflets are inequilateral, ovate to oblong-ovate, 5 to 8 centimeters long

4

and half as wide, pointed at the tip, broadly obtuse or rounded at the base. Flowers are

greenish yellow, about 8 millimeters wide, born in axillary pannicles shorter than the

foliage. Body of the fruit splits into five thick outer valves and five thinner inside valves.

The outer valves fall off when ripe exposing closely packed seeds attached by the tips of

their wings. Seeds are brownish, 5 to 7 centimeters long, with a broad and thin wing and

a corky, thickened part containing the embryo.

In this study, mahogany is a test organism taken from the polluted areas of Iloilo

City. The air pollution tolerance index of mahogany was calculated to determine if it is

sensitive to air pollution.

Bougainvillea (Bougainvillea spectabilis)

Bougainvillea is a woody climber that can grow to a height of more than 10

meters, with large thorny stems and long drooping branches. The leaves are dark green,

petioled, alternate, ovate, with entire margins, 6 to 10 centimeters long, broadest near the

base. Thorns are the axils assist the plant in climbing. Flowers are in groups of threes,

forming clusters at the terminal portion of the branches, each group subtended by three,

broad, purplish, oblong-ovate and acuminate bracts, about 3 to 5 centimeters long.

Flowers are small, each inserted on a bract, tubular, inflated midway through its length,

of varying colors.

In this study, bougainvillea is a test organism taken from the polluted areas of

Iloilo City. The air pollution tolerance index of bougainvillea was calculated to determine

if it is sensitive to air pollution.

Relative leaf water content (RWC)

Relative water content is the amount of water a plant contains when it is incapable

of taking in more water. This state is known as full saturation. A plant does not need to be

in this state in order to survive but, knowing the percentage of water a plant is capable of

holding is one way to determine if a plant is stressed. The high water content within a

plant body will help to maintain its physiological balance under stress condition such as

exposure to air pollution when the transpiration rates are usually high. High RWC favors

5

drought resistance in plants. If the leaf transpiration rate reduces due to the air pollution,

plant cannot live well due to losing its engine that pulls water up from the roots to supply

photosynthesis (1%-2% of the total). Then, the plants neither bring minerals from the

roots to leaf where biosynthesis occurs, nor cool the leaf (Liu and Ding, 2008).

In this study, relative leaf water content (RWC) is one of the parameters that was

determined to calculate the air pollution tolerance index of plants.

Total Chlorophyll Content (T)

Total chlorophyll content is defined as the product of leaf chlorophyll content and

total leaf area index. Depletion in chlorophyll immediately causes a decrease in

productivity of plant and subsequently plant exhibits poor vigor. Therefore, plants

maintaining their chlorophyll even under polluted environment are said to be tolerant

ones (Singh and Verma, 2007).

In this study, total chlorophyll content (T) is one of the parameters that was

determined to calculate the air pollution tolerance index of plants.

Leaf extract pH

Leaf extract pH is the pH of the extracts of the leaves of the plant. It can be

determined using a pH meter calibrated with buffer solution of pH 4 and 9. High leaf

extract pH may increase the efficiency of conversion from hexose sugar to AA, while low

leaf extract pH showed good correlation with sensitivity to air pollution. Photosynthetic

efficiency was noted strongly dependent on leaf pH. Photosynthesis is reduced in plants

when the leaf pH was low (Liu and Ding, 2008). Plants with low lower pH are more

susceptible to air pollution, while those with pH around 7 are more tolerant (Singh and

Verma, 2007).

In this study, leaf extract pH is one of the parameters that was determined to

calculate the air pollution tolerance index of plants.

6

Ascorbic Acid (AA) content

Ascorbic acid content is the amount of ascorbic acid present in the leaf of a plant.

It is measured using iodine titration. Ascorbic acid plays a role in cell wall synthesis,

defense, and cell division. It is a strong reducer and plays important roles in

photosynthetic carbon fixation, with the reducing power directly proportional to its

concentration (Liu and Ding, 2008). It also plays a significant role in light reaction of

photosynthesis, activates defense mechanism, and under stress condition, it can replace

water from light reaction. Ascorbic acid in plants has been shown to play an important

role in pollution tolerance (Seyyednjad and others, 2011).

In this study, ascorbic acid content is one of the parameters that was determined

to calculate the air pollution tolerance index of plants.

Air Pollution Tolerance Index (APTI)

The air pollution tolerance index (APTI) is used to determine the sensitivity of

plant species when exposed to polluted air. It is used by landscapers to select plant

species that are tolerant to air pollution. The plant species with APTI value that is less

than 16 is considered sensitive and act as a bioindicator of air pollution; APTI value

within 17 to 29 is considered intermediate and greater than 17 is tolerant to air pollution

(Liu and Ding, 2008).

In this study, air pollution tolerance index was used to determine the sensitivity

and tolerance of plants to air pollution.

7

CHAPTER II

REVIEW OF RELATED LITERATURE

A. Air Pollution Tolerance Index (APTI)

Sensitivity and response of plants to air pollutants is variable. Air pollution

tolerance index is used to determine plant species that are tolerant to air pollution

(Agbaire, 2009 as cited by Seyyednjad and others, 2011). The usefulness of evaluating

APTI for the determination of tolerance as well as sensitiveness of plant species provided

valuable informations for landscapers and greenbelt designers to select the sensitive as

well as tolerant varieties of plant species (Jyothi and Jaya, 2010). The plant species with

APTI value that is less than 16 is considered sensitive and act as a bioindicator of air

pollution; APTI value within 17 to 29 is considered intermediate and greater than 30 is

tolerant to air pollution (Liu and Ding, 2008). There are four parameters used to measure

the APTI of plants: the relative leaf water content (RWC), the total chlorophyll content

(T), the leaf extract pH, and the ascorbic acid (AA) content. These four parameters are

calculated to attain the APTI values for each plant. For the reason that single parameter

may not provide a clear picture of pollution-induced changes, air pollution tolerance

index (APTI) based on all four parameters has been used to identify the tolerance levels

of plant species (Liu and Ding, 2008).

Ascorbic acid plays a role in cell wall synthesis, defense, and cell division. It is

also a strong reducer and plays important roles in photosynthetic carbon fixation, with the

reducing power directly proportional to its concentration. So it has been given top priority

and used as a multiplication factor in the formula. High pH may increase the efficiency of

conversion from hexose sugar to AA, while low leaf extract pH showed good correlation

with sensitivity to air pollution. Meanwhile, T, the TCh is also related to AA productivity

and AA is concentrated mainly in chloroplasts. Photosynthetic efficiency was noted

strongly dependent on leaf pH. Photosynthesis reduced in plants when the leaf pH was

low. Thus, in the proposed APTI formula, P, the leaf extract pH and T, the TCh have

been added together and then multiplied with AA content. A high water content within a

plant body will help to maintain its physiological balance under stress condition such as

exposure to air pollution when the transpiration rates are usually high. High RWC favors

8

drought resistance in plants. If the leaf transpiration rate reduces due to the air pollution,

plant cannot live well due to losing its engine that pulls water up from the roots to supply

photosynthesis (1%-2% of the total). Then, the plants neither bring minerals from the

roots to leaf where biosynthesis occurs, nor cool the leaf. Therefore, the product of AA

and sum of leaf extract pH and total chlorophyll is added with R, the RWC in the APTI

formula (Liu and Ding, 2008).

A.1 Relative Leaf Water Content

Relative water content is the amount of water a plant contains when it is

incapable of taking in more water. This state is known as full saturation. A plant

does not need to be in this state in order to survive but, knowing the percentage of

water a plant is capable of holding is one way to determine if a plant is stressed.

The high water content within a plant body will help to maintain its physiological

balance under stress condition such as exposure to air pollution when the

transpiration rates are usually high. High RWC favors drought resistance in

plants. If the leaf transpiration rate reduces due to the air pollution, plant cannot

live well due to losing its engine that pulls water up from the roots to supply

photosynthesis (1%-2% of the total). Then, the plants neither bring minerals from

the roots to leaf where biosynthesis occurs, nor cool the leaf (Liu and Ding,

2008).

A.2 Total Chlorophyll Content (T)

Total chlorophyll content is defined as the product of leaf chlorophyll

content and total leaf area index. Depletion in chlorophyll immediately causes a

decrease in productivity of plant and subsequently plant exhibits poor vigor.

Therefore, plants maintaining their chlorophyll even under polluted environment

are said to be tolerant ones (Singh and Verma, 2007).

A.3 Leaf extract pH

Leaf extract pH is the pH of the extracts of the leaves of the plant. It can

be determined using a pH meter calibrated with buffer solution of pH 4 and 9.

High leaf extract pH may increase the efficiency of conversion from hexose sugar

9

to AA, while low leaf extract pH showed good correlation with sensitivity to air

pollution. Photosynthetic efficiency was noted strongly dependent on leaf pH.

Photosynthesis is reduced in plants when the leaf pH was low (Liu and Ding,

2008). Plants with low lower pH are more susceptible to air pollution, while those

with pH around 7 are more tolerant (Singh and Verma, 2007).

A.4 Ascorbic Acid (AA) content

Ascorbic acid content is the amount of ascorbic acid present in the leaf of

a plant. It is measured using iodine titration. Ascorbic acid plays a role in cell wall

synthesis, defense, and cell division. It is a strong reducer and plays important

roles in photosynthetic carbon fixation, with the reducing power directly

proportional to its concentration (Liu and Ding, 2008). It also plays a significant

role in light reaction of photosynthesis, activates defense mechanism, and under

stress condition, it can replace water from light reaction. Ascorbic acid in plants

has been shown to play an important role in pollution tolerance (Seyyednjad and

others, 2011).

B. Bioindicators

A bioindicator is an organism or biological response that reveals the presence of

the pollutants by the occurrence of typical symptoms or measurable responses, and is

therefore more qualitative. These organisms (or communities of organisms) deliver

information on alterations in the environment or the quantity of environmental pollutants

by changing in one of the following ways: physiologically, chemically or behaviourally.

Bioindicator plant species are species with high sensitivity to ozone. This

sensitivity is manifested in changes in physiological parameters, biomass reduction and

the appearance of specific visible symptoms when exposed to high levels of ozone.

According to the extent of these injuries, conclusions can be drawn regarding the

presence (and, for some extent, the amount) of ozone in the atmosphere of the site where

the plants are exposed to ambient air. In addition, ozone bioindicator plants are widely

used in researches aiming to clarify plant’s response to the stressor, or, in general, to

10

oxidative stress. Reduction in biomass of sensitive clones as an effect of ozone is also a

widely investigated indicative feature of biomonitoring plants.

C. Air Pollution

Air pollution is a major problem arising mainly from industrialization (Odilara

and others, 2006 as cited by Seyyednjad and others, 2011). Air pollution is the human

introduction into the atmosphere of chemicals, particulate matter, or biological materials

that cause harm or discomfort to humans or other living organism, or damage to the

environment. Pollutants could be classified as either primary or secondary. Pollutants that

are pumped into the atmosphere and directly pollute the air are primary pollutants while

those that are formed in the air when primary pollutants react or interact are known as

secondary pollutant (Agbaire and Esiefarienrhe, 2009 as cited by Seyyednjad and others,

2011).

C.1 Effects of Air Pollution on Humans

The health effects of air pollution have been subject to intense study in

recent years. Exposure to pollutants such as airborne particulate matter and ozone

has been associated with increases in mortality and hospital admissions due to

respiratory and cardiovascular disease. These effects have been found in short-

term studies, which relate day-to-day variations in air pollution and health, and

long-term studies, which have followed cohorts of exposed individuals over time.

Effects have been seen at very low levels of exposure, and it is unclear whether a

threshold concentration exists for particulate matter and ozone below which no

effects on health are likely.

A third cohort study (AHSMOG) found significant effects of particulate

matter with a diameter of less than 10 µm (PM10) on non-malignant respiratory

deaths in men and women, and on lung-cancer mortality in male, non-smoking

Seventh-Day Adventists.The effect on shortening life expectancy has been

estimated at 1–2 years for realistic exposure contrasts, which is substantial

compared with the effects of other lifestyle or environmental risk factors related

11

to mortality. Study show that the findings persist after inclusion of several more

years of observation, with more consistent effects on lung cancer, in addition to

non-malignant cardiopulmonary deaths. A Dutch study suggests that exposure to

traffic-related air pollution is associated with cardiorespiratory deaths in much the

same way as in the USA. For millions of people living in rural areas in developing

countries, indoor pollution from the use of biomass fuels occurs at concentrations

that are orders of magnitude higher than currently seen in the developed world.

Deaths due to acute respiratory infections in children resulting from these

exposures are estimated to be over 2 million per year (Brunekreef and Holgate,

2002).

C.2 Effects of Air Pollution on Plants

Several contributors agree that air pollution affects plant growth

adeversely (Rao, 2006 as cited by Seyyednjad and others, 2011). In spite of the

adverse affections of these pollutants, there are still plants that are tolerant to air

pollution (Nivane and others, 2001 as cited by Seyyednjad and others, 2011).

Plants play an important role in monitoring and maintaining ecological balance by

actively participating in the cycling of nutrients and gases (Seyyednjad and others,

2011). Also, plants are an integral basis for all ecosystems and most likely to be

affected by airborne pollution which are identified as the organisms with most

potential to receive impacts from ambient air pollution. The effects are most often

apparent on the leaves which are usually the most abundant and most obvious

primary receptors of large number of air pollutants. Biomonitoring of plants is an

important tool to evaluate the impact of air pollution (Jyothi and Jaya, 2010).

Studies show that air pollution has an impact on the ascorbic acid content,

chlorophyll content, leaf extract pH, and relative water content of plants. The

response of plants to air pollution at physiological and biochemical levels can be

understood by analyzing the factors determining resistance and susceptibility

(Seyyednjad and others, 2011).

12

There are three principal air pollutants of major interest to agriculture –

sulfur dioxide, fluorine compounds, and smog (Thomas, 1963).

C.2.1 Sulfur Dioxide

The effects of sulfur dioxide on plants are fairly well understood.

The gas is absorbed into the mesophyll of the leaves through the stomata.

Toxicity is due largely to the reducing properties of the gas. The limiting

concentration that can be tolerated in the cells is about the same for many

diverse species, including water plants. When this concentration is

exceeded, the cells are first ion activated with or without plasmolysis, then

killed. When extensive areas are killed, the tissues collapse and dry up,

leaving a characteristic pattern of interveinal and marginal acute injury.

Sulfate toxicity is a form of chronic injury manifested by white or

brownish-red turgid areas on the leaf caused by the rupture of some cells

or of chloroplasts within the cells (Thomas, 1963).

C.2.2 Fluorine Compounds

Fluorides have great importance as air pollutants. Hydrogen

fluoride and silicon tetrafluoride are toxic to some plants and fluorides

particulates accumulate and build up concentrations on the inside and

outside of the leaves causing marginal necrosis. Insoluble fluoride salts

may be precipitated in the tissue, reducing the activity of the element.

Fluorides can inhibit certain plant enzymes in very low concentrations

(Thomas, 1963).

C.2.3 Smog

Smog is a complex mixture of gases. There at least two types of

smog: (1) mixture of coal smoke and fog with sulfur dioxide and (2)

mixture of ozone and preoxidized organic compounds formed by

photochemical reactions. Smog causes injury to the leaves giving it white

or spotted collapsed areas on the upper surface. The chloroplasts of the

13

plants exposed to smog disintegrate, plasmolysis then follows, and total

dehydration of damaged cells results in "mummification" of the mesophyll

tissue in the affected areas (Thomas, 1963).

D. Plant Species

D.1 Santan (Ixora coccinea)

Santan is an erect and smooth ornamental shrub, growing to a height of 2

to 3 meters. Leaves are stalkless or on very short stalks, oblong, 5 to 9 centimeters

long, heart-shaped or rounded at the base and blunt-tipped. Flowers are many,

pink or red, and borne in terminal, stalkless or shortly stalked, hairy cymes. Calyx

teeth are short and pointed. Corolla-tube is slender, 2.5 centimeters long; lobes are

spreading and oblong, about half the length of the tube. Fruit is reddish, almost

round, about 5 millimeters in diameter.

In this study, santan is a test organism taken from the polluted and

unpolluted parts of Iloilo City. The air pollution tolerance index of santan was

calculated to determine if it is sensitive or tolerant to air pollution.

D.2 Mahogany (Swietenia macrophylla)

Mahogany is a deciduous, erect tree growing to a height of 10 meters, with

a heavy, dark-green, and dense crown. The trunk is more or less buttressed. Bark

is dark gray and ridged. Young leaves when in the flush are pink, soon turning

green. Leaves are alternate, smooth, compound, about 15 centimeters long, in 3 to

6 pairs, most often 5 pairs, of leaflets. Leaflets are inequilateral, ovate to oblong-

ovate, 5 to 8 centimeters long and half as wide, pointed at the tip, broadly obtuse

or rounded at the base. Flowers are greenish yellow, about 8 millimeters wide,

borne in axillary pannicles shorter than the foliage. Calyx is rimlike and the petals

are oblong, less than 5 millimiters in length. Staminal tube is sligtly reddish,

thick, and nearly as long as the corolla. Fruit is large, cylindrical, barrel-shaped,

woody, grayish-brown, rough and less than 12 centimeters long. Body of the fruit

14

splits into five thick outer valves and five thinner inside valves. The outer valves

fall off when ripe exposing closely packed seeds attached by the tips of their

wings. Seeds are brownish, 5 to 7 centimeters long, with a broad and thin wing

and a corky, thickened part containing the embryo.

In this study, mahogany is a test organism taken from the polluted and

unpolluted parts of Iloilo City. The air pollution tolerance index of mahogany was

calculated to determine if it is sensitive or tolerant to air pollution.

D.3 Bougainvillea (Bougainvillea spectabilis)

Bougainvillea is a woody climber that can grow to a height of more than

10 meters, with large thorny stems and long drooping branches. The leaves are

dark green, petioled, alternate, ovate, with entire margins, 6 to 10 centimeters

long, broadest near the base. Thorns are the axils assist the plant in climbing.

Flowers are in groups of threes, forming clusters at the terminal portion of the

branches, each group subtended by three, broad, purplish, oblong-ovate and

acuminate bracts, about 3 to 5 centimeters long. Flowers are small, each inserted

on a bract, tubular, inflated midway through its length, of varying colors.

In this study, bougainvillea is a test organism taken from the unpolluted

and polluted areas of Iloilo City. The air pollution tolerance index of

bougainvillea was calculated to determine if it is sensitive or tolerant to air

pollution.

E. Related Studies

E.1 Air Pollution Tolerance Indices of Some Plants Around Industrial Zone

in South of Iran

In the study of Seyyednjad and others (2011), the Air Pollution Tolerance

Index of four plant species around petrochemical station in south west of Iran

were examined.

15

The samples were taken from the tree species in two places, polluted area

and unpolluted area. Plants were randomly selected from the immediate vicinity

of the station. Three replicates of fully matured leaves were used and immediately

taken to the laboratory in the ice for analysis. The experiments were replicated

three times for each biological factor. Air Pollution Tolerance Index was

measured using the four parameters: relative leaf water content (RWC), total

chlorophyll content (T), leaf extract pH, and ascorbic acid (AA) content.

The result showed order of tolerance in polluted area as E. camaldulensis

(8/5) > A. lebbeck (8/1) > C. salignus (7/9) > P. juliflora (5/8) and in unpolluted

area as E. camaldulensis (8/4) > A. lebbeck (6/7) > C. salignus (6/2) > P. juliflora

(6/6). The results show that in cases that APTI increase from control site to

polluted site improve the species tolerance to pollution stress.

All the samples are sensitive ones (1<APTI<16). However, P. juliflora is

the most sensitive and its APTI showed reduction in polluted site as compared

with control site. In conclusion, C. salignus, A. lebbeck, E. camaldulensis and P.

juliflora can be used as bioindicators of air pollution.

E.2 Evaluation of air pollution tolerance index of selected plant species

along roadsides in Thiruvananthapuram, Kerala

In the study of Jyothi and Jaya (2010), a periodic evaluation of air

pollution tolerance index (APTI) of selected tree species such as Polyalthia

longifolia, (Sonner) Thw., Alstonia scholaris, R. Br., Mangifera indica, L., and

shrubs Clerodendron infortunatum, L., Eupatorium odoratum, L., and Hyptis

suaveolens, (L.) Poit., growing adjacent to the National Highway – 47 passing

through Thiruvananthapuram District which lies on the south-west coast of India,

was carried out with a view to find out the air pollution tolerance as well as

sensitivity of the plant species during different seasons.

16

Among the trees in the roadside areas studied, Polyalthia longifolia,

(Sonner) Thw., expressed highest APTI values and proved to be a tolerant variety

and the others as sensitive species to air pollutants. In the case of shrubs,

Clerodendron infortunatum, L., exhibited highest APTI values (7.34) and found to

be more tolerant compared to the other two shrub species studied.

E.3 Variation in air pollution tolerance index of plants near a steel factory:

Implications for landscape-plant species selection for industrial areas

In the study of Liu and Ding (2008), twenty-three plant species growing

near a Beijing steel factory, an air pollution point source, were collected during

five dates from July 1 to October 16, 2001.

The data suggested that combining a variety of physiological parameters

could give a more reliable result than those air pollution tolerance classifications

based on a single biochemical parameter. Through the growing season, some

species exhibited APTI variation related to changes in air temperature and water

status of the plant. The results highlighted the need for APTI measurements to be

conducted throughout the growing season, when evaluating pollution tolerance of

individual species. Plant species tolerant or moderately tolerant to air pollution

under a variety of environmental conditions include non-trees (shrub, herb, vine)

such as Metaplexis japonica, Ampelopsis aconitifolia var. glabra, Rhamnus

parvifolia, Ziziphus jujuba var. spinosa, Pharbitis purpurea, Vitex negundo, and

trees including Broussonetia papyrifera, Robinia pseudoacacia, and Ailanthus

altissima. The APTI of species indicated as an ideal candidate for landscape

planting in the vicinity of polluting industry.

E.4 Evaluation of Air Pollution Tolerance Index (APTI) Of Some Selected

Ornamental Shrubs in Enugu City, Nigeria

In the study of Enete and Ogbonna in 2012, five species of ornamental

shrubs that were growing along central business district (CBD) of Enugu Urban

City of Nigeria were selected and evaluated for its air pollution tolerance index.

17

Result indicates that ornamental shrubs had varied degree of tolerance

index to air pollution. The air pollution tolerance index ranged from 10.60 to

14.32 with Ixora Red having the highest APTI value and Yellow Bush with

lowest APTI value. The data suggested that ornamental shrubs growing in

polluted environment often respond and show significant changes in their

morphology, physiology and biochemistry. In this study, the orders of tolerance of

ornamental shrubs are in this order: Ixora Red, Yellow Ficus, Masquerade Pine,

Tuja Pine, and Yellow bush. The implication is that Ixora Red should be preferred

where pollution appears high because of its ability to tolerate more pollutants.

Ornamental shrubs like Yellow Bush showed are used as indicators of poor air

quality.

18

CHAPTER 3

METHODOLOGY

A. Preliminary Parts

A.1 Overview of the Study

This study aimed to determine the air pollution tolerance index of three plant species


the polluted and unpolluted areas of Iloilo City. Specifically, this study aimed to:

determine and calculate the relative leaf water content (RWC) of three plant species


the polluted and unpolluted areas of Iloilo City, determine and calculate the total

chlorophyll content (T) of three plant species (Ixora coccinea, Swietenia macrophylla,

Bougainvillea spectabilis) commonly found in the polluted and unpolluted areas of Iloilo

City, determine and calculate the leaf extract pH of three plant species (Ixora coccinea,

Swietenia macrophylla, Bougainvillea spectabilis) commonly found in the polluted and

unpolluted areas of Iloilo City and, determine and calculate the ascorbic acid (AA)

content of three plant species (Ixora coccinea, Swietenia macrophylla, Bougainvillea

spectabilis) commonly found in the polluted and unpolluted areas of Iloilo City.

Three plant species (Ixora coccinea, Swietenia macrophylla, Bougainvillea

spectabilis) were used in this study. Leaf samples were taken from the polluted and

unpolluted parts of Iloilo City. Plants were randomly selected from the immediate

vicinity of the station.

A.2 Time and Place of Study

The samples for the study were taken from the polluted and unpolluted areas of

Iloilo City. Laboratory works were conducted at Philippine Science High School –

Western Visayas Campus Research Laboratory. The study was conducted between the

months of December 2012 and January 2013.

19

A.3. Description of Study or Sampling site/s

Leaf samples for the polluted area were taken from Philippine Science High

School – Western Visayas Campus (PSHSWVC). PSHSWVC is located in Brgy. Bitoon,

Jaro, Iloilo City, a highly populated barangay, and near the floodway of Iloilo River,

whose water goes directly to the Iloilo Strait. The school is approximately less than 7

kilometers away from the Panay Power BFO Plant which emits black smoke during

operation. Also, cars and jeepneys would pass by at the school campus approximately

every 10 minutes.

On the other hand, leaf samples for the unpolluted area were taken from Barangay

Balabag, Pavia, Iloilo. Pavia is a town located in the province of Iloilo. The location is

surrounded by empty fields, some residential houses and approximately 1 kilometer away

from the road.

B. Methodology

B.1 Preparation of Materials and Equipment

B.1.1 Choosing of Plants and Collection of Leaves

Three plant species (Ixora coccinea, Swietenia macrophylla, Bougainvillea

spectabilis) were used in the experiment. Leaf samples were taken from the polluted and

unpolluted parts of Iloilo City. Plants were randomly selected from the immediate

vicinity of the station. Three replicates of fully matured leaves were used. The leaves

from each plant were selected randomly.

B.2 Preparation of Study Area

The study was conducted on the polluted and unpolluted parts of Iloilo City.

Plants were randomly selected from the immediate vicinity of the station. Laboratory

works were held at Philippine Science High School – Western Visayas Research

Laboratory.

B.3 Measurement of the Air Pollution Tolerance Index (APTI) of the Plants

20

B.3.1 Measurement of the Total Relative Leaf Water Content (RWC)

The Total Relative Leaf Water Content was determined according to the

method described by Liu and Ding (2008). Fresh weight was obtained by

weighing the fresh leaves. The leaves were immersed with water over night, were

blotted dry and were weighed to get the turgid weight. The leaves were then dried

overnight in an oven at 70°C and were weighed again to obtain the dry weight.

The Relative Leaf Water Content was calculated using the formula:

RWC=( Fw−Dw )(Tw−Dw )

x100 %Where:

Fw = fresh weight

Dw = dry weight

Tw = turgid weight

B.3.2 Measurement of the Total Chlorophyll Content (T)

The Total Chlorophyll Content was determined using the method

described by Lichtenthaler (1987). 0.2 g of fresh leaves was blended and was

extracted with 10 mL of 80% acetone and left for 15 minutes. The liquid portion

was decanted into another test-tube and centrifuged at 2,500 rpm for 3 minutes.

The supernatant was collected and the absorbance was taken at 645 nm and

663nm using a spectrophotometer. Calculations were made using the formula:

CT=20.2 ( D 645 )+8.02(D 663)

TC h=0.1 CT ×( leaf Dwleaf Fw

)

B.3.3 Measurement of the Leaf Extract pH

Five grams of fresh leaves were homogenized in 10 mL deionized water.

This was filtered and the pH of the leaf extract was determined after calibrating

the pH meter with the buffer solution of pH 4 and 9.

B.3.4 Measurement of the Ascorbic Acid (AA) Content

21

2 g of potassium iodide was placed into a 100 mL beaker and 1.3 g of

iodine crystals were added into the same beaker. A few mL of distilled water was

added and swirled for a few minutes until the iodine crystals were dissolved.

Iodine solution was transferred to a 1 L volumetric flask. A 1 L solution was

made by adding distilled water up to the 1 L mark. 0.25 g of soluble starch was

weighed and was added to 50 mL of near boiling water in a 100 mL conical flask.

The solution was stirred and cooled before using. 100 g sample was cut into small

pieces and was homogenized using a blender. 100 mL of distilled water was

added while blending the sample. The grounded leaf was strained using a

cheesecloth. The extracted solution was be made up to 100 mL with distilled

water.

The average volume of iodine solution used from the concordant titres and

the moles of iodine reacting was calculated using the equation of the titration

(below) to determine the number of moles of ascorbic acid reacting.

ascorbic acid + I2 → 2 I− + dehydroascorbic acid

Then the concentration in mol L−1 of ascorbic acid in the solution

obtained from plant extract was calculated. Also, the concentration in g/mg Dw of

ascorbic acid in the sample of plant was calculated.

B.3.5 APTI determination

The air pollution tolerance indices of the three plants was determined

using the formula by Liu and Ding (2008). The formula for solving the APTI is

given as:

APTI=[ A (T+P )+R ]

10

Where:

A= Ascorbic acid content (mg/g Dw)

T= Total Chlorophyll Content (mg/g Dw)

P= pH of leaf extract

22

R= Relative leaf water content (%)

C. Safe Handling of Chemicals

Chemical containers were kept and labeled properly. The date when the chemical was

received and was opened was recorded. Expiration dates and special storage conditions of

chemicals were noted. All equipment were used for its designated purpose.

D. Safety Procedures in the Work Area

The laboratory was kept clean and free of equipment that are not relevant to the work.

Work surfaces were disinfected after any spillage of possibly hazardous chemicals. Proper

laboratory outfit was worn at all times while inside the laboratory. Close-toed shoes were

worn inside the laboratory. Hands were washed before leaving the laboratory.

E. Waste Disposal and After-care of the Work Area

All materials and equipment that were used were cleaned after the experiment. The oven

was thoroughly cleaned. The tables that were used for laboratory work was cleaned before

and after use. After the laboratory work, the chemicals and apparatus should be returned to

their designated areas. Spilled chemicals or broken glassware should be cleaned up, and

disposed in appropriate waste containers. Soiled glassware should be cleaned at the

laboratory sink or in laboratory dishwashers.

CHAPTER 4

23

RESULTS AND DISCUSSION

This study aimed to determine the air pollution tolerance index (APTI) of three plant

species (Ixora coccinea, Swietenia macrophylla, Bougainvillea spectabilis) commonly found in

the polluted and unpolluted areas of Iloilo City. This was done by determining the total

chlorophyll content (TCh), leaf extract pH, ascorbic acid content (AA), and relative leaf water

content (RWC). Plant species with APTI value that is less than 16 is considered sensitive and act

as a bioindicator of air pollution; APTI value within 17 to 30 is considered intermediate and

greater than 30 is tolerant to air pollution (Liu and Ding, 2008).

Three plant species (Ixora coccinea, Swietenia macrophylla, Bougainvillea spectabilis)

were used in the experiment. Leaf samples were taken from Philippine Science High School –

Western Visayas Campus and Barangay Balabag, Pavia, Iloilo City. Plants were randomly

selected from the immediate vicinity of the station. Leaf samples were brought to the laboratory

for evaluation of total chlorophyll content (TCh), leaf extract pH, ascorbic acid content (AA),

and relative leaf water content (RWC). Three trials were done during the months of December

2012 and January 2013. The APTI values of the plants were calculated using the formula of Liu

and Ding (2008).

A. Results

Table1: Total chlorophyll content (TCh), Leaf extract pH, Ascorbic acid content (AA), Relative leaf water content (RWC), and air pollution tolerance index (APTI) of three plant species from Philippine Science High School– Western Visayas Campus.

Philippine Science High School- Western Visayas

(PSHSWV)

Relative Leaf Water Content (%)

Total Chlorophyll Content (mg/g Dw)

Leaf Extract pH

Ascorbic Acid Content (mg/g Dw)

APTI

Santan

(Ixora coccinea)8.40 0.40 5.33 21.66 13.25

Mahogany

(Swietenia macrophylla)46.16 0.53 5.97 108.99 75.46

Bougainvillea

(Bougainvillea spectabilis)18.55 1.19 6.47 14.47 12.94

Table2: Total chlorophyll content (TCh), Leaf extract pH, Ascorbic acid content (AA), Relative leaf water content (RWC), and air pollution tolerance index (APTI) of three plant species from Barangay Balabag,

24

Pavia, IloiloPAVIA

Relative Leaf Water Content (%)


Leaf Extract pH


APTI

Santan

(Ixora coccinea)32.85 0.48 6.16 27.77 21.72

Mahogany


Bougainvillea


Table 1 and 2 shows the total chlorophyll content (TCh), leaf extract pH, ascorbic acid

content (AA), relative leaf water content (RWC), and air pollution tolerance index of the plant

species from Philippine Science High School – Western Visayas Campus and Barangay Balabag,

Pavia, Iloilo City as quantified during the months of December 2012 and January 2013.

The air pollution tolerance indices of Mahogany (Swietenia macrophylla), Bougainvillea

(Bougainvillea spectabilis) and Santan (Ixora coccinea) from PSHSWV are 75.46, 12.94 and

13.25, respectively. While, the air pollution tolerance indices of Mahogany (Swietenia

macrophylla), Bougainvillea (Bougainvillea spectabilis) and Santan (Ixora coccinea) from

Barangay Balabag, Pavia are 73.68, 7.18 and 21.72, respectively. Since, the APTI value of

Mahogany (Swietenia macrophylla) is greater than 30 it shows that it is tolerant to air pollution

while the APTI values of Bougainvillea (Bougainvillea spectabilis) and Santan (Ixora coccinea)

indicates that these plant species are sensitive to air pollution since its APTI value is less than 16.

Table 3: T-Test results of the APTI values of plant species from PSHSWV and Brgy. Balabag, Pavia.

APTI value T-Test ResultsSantan PSHSWV

Significant DifferencePavia

Bougainvillea PSHSWVSignificant Difference

PaviaMahogany PSHSWV No Significant

DifferencePavia

The air pollution tolerance indices of the three plant species from Philippine Science

25

High School – Western Visayas Campus and Barangay Balabag, Pavia, Iloilo were compared

using the independent t-test. As shown in Table 3, the air pollution tolerance indices of

Mahogany (Swietenia macrophylla) from the two study sites were found to be statistically

insignificant. This proves the assumption that Mahogany is tolerant to air pollution while, the air

pollution tolerance indices of Bougainvillea and Santan were found to be statistically significant.

A significant difference between the APTI values would mean that a plant is sensitive to air

pollution, making its values differ significantly when exposed to a more polluted air. This also

proves the assumption that Bougainvillea and Santan are sensitive to air pollution.

B. Discussion

Air pollution tolerance index (APTI) is used to determine plant species that are tolerant to

air pollution (Agbaire, 2009 as cited by Seyyednjad and others, 2011). The purpose of evaluating

APTI for the determination of tolerance as well as sensitiveness of plant species could provide

valuable information for landscapers and greenbelt designers to select the sensitive as well as

tolerant varieties of plant species (Jyothi and Jaya, 2010). The plant species with APTI value that

is less than 16 is considered sensitive and act as a bioindicator of air pollution; APTI value

within 17 to 29 is considered intermediate and greater than 30 is tolerant to air pollution (Liu and

Ding, 2008). There are four parameters used to measure the APTI of plants: the relative leaf

water content (RWC), the total chlorophyll content (T), the leaf extract pH, and the ascorbic acid

(AA) content. These four parameters are calculated to attain the APTI values for each plant.

Ascorbic acid plays a role in cell wall synthesis, defense, and cell division. It plays important

roles in photosynthetic carbon fixation, with the reducing power directly proportional to its

concentration. So it has been used as a multiplication factor in the formula. High pH may

increase the efficiency of conversion from hexose sugar to AA. Meanwhile, the TCh is also

related to AA productivity and AA is concentrated mainly in chloroplasts. Thus, in the proposed

APTI formula, the leaf extract pH and the TCh have been added together and then multiplied

with AA content. The high water content within a plant body will help to maintain its

physiological balance under stress condition such as exposure to air pollution. Therefore, the

product of AA and sum of leaf extract pH and total chlorophyll is added with the RWC in the

APTI formula (Liu and Ding, 2008).

26

The air pollution tolerance indices of Santan (Ixora coccinea) and Bougainvillea

(Bougainvillea spectabilis) are less than 16 which mean that these plant species are sensitive to

air pollution. The low APTI value of Santan is attributed to its low ascorbic acid content and to

its low total chlorophyll content. The low chlorophyll content in plants would result to low

ascorbic acid content (Liu and Ding, 2008). Although Bougainvillea has the highest total

chlorophyll content of the three plant species, the leaf extract pH is slightly acidic which means

that the pH is slightly low. Since high pH may increase the efficiency of conversion from hexose

sugar to AA and the pH of bougainvillea is slightly low, this would be the possible reason why

the ascorbic acid content of bougainvillea is also low. Ascorbic acid plays a role in cell wall

synthesis, defense, and cell division. It is also a strong reducer and plays important roles in

photosynthetic carbon fixation, with the reducing power directly proportional to its concentration

(Liu and Ding, 2008). Bougainvillea also has the lowest relative leaf water content among the

three plant species. The high water content within a plant body will help to maintain its

physiological balance under stress condition such as exposure to air pollution when the

transpiration rates are usually high. High RWC favors drought resistance in plants. If the leaf

transpiration rate reduces due to the air pollution, plant cannot live well due to losing its engine

that pulls water up from the roots to supply photosynthesis by 1%-2% of the total. Then, the

plants neither bring minerals from the roots to leaf where biosynthesis occurs, nor cool the leaf

(Liu and Ding, 2008). As a result, the APTI value of bougainvillea is low, making it a

bioindicator for air pollution.

The air pollution tolerance index of Mahogany (Swietenia macrophylla) is greater than

30 which indicate that it is tolerant to air pollution. The high APTI value of this plant species is

attributed to its high ascorbic acid (AA) content. Mahogany contains 118.95 g/mg Dw ascorbic

acid. Ascorbic acid is a multiplication factor in the formula for solving APTI therefore; a high

content of ascorbic acid in plant leaves would result to a high value of APTI for the plant.

The values of the APTI acquired from the two different locations were compared using

an independent t-test. The two study sites were Philippine Science High School – Western

Visayas Campus (PSHSWVC) and Brgy. Balabag, Pavia, Iloilo. PSHS-WVC is located in Brgy.

Bitoon, Jaro, Iloilo City, a highly populated barangay, and near the floodway of Iloilo River,

whose water goes directly to the Iloilo Strait. It is near the Panay Power BFO Plant which emits

27

black smoke during operation. Cars and jeepneys would pass by at the school campus from time

to time. The other site is found at Brgy. Balabag, Pavia, Iloilo. Pavia is a town located in the

province of Iloilo. The location is surrounded by empty fields, some residential houses and is far

from the road.

It was found out that the APTI values of Santan (Ixora coccinea) from the two study sites

has a significant difference thus, proving that it is sensitive to air pollution and can act as a

bioindicator. The APTI values of Bougainvillea (Bougainvillea spectabilis) from the two study

sites were also found to be having a significant difference, thus making it acceptable to be used

as a bioindicator for polluted air. A significant difference between the APTI values would mean

that a plant is sensitive to air pollution, causing the values to differ significantly when exposed to

a more polluted air. While, the APTI values of Mahogany (Swietenia macrophylla) from the two

study sites are found to be having no significant difference and this proves the assumption that

Mahogany (Swietenia macrophylla) is tolerant to air pollution and cannot act as a bioindicator

for air pollution. The result of the current study becomes handy for future planning. The study

also provides useful information for selecting tolerant species for streetscaping and microclimate

modification. Species that are tolerant should be considered in advance for use; especially where

air pollution is high conversely, species that are found to be sensitive should be utilized as

bioindicators of urban air quality (Enete and Ogbonna, 2012). The analyses made agree with the

study of Liu and Ding in 2008.

APTI does not necessarily indicate if the location is polluted or not. The indication of air

pollution is depends on whether the plant would survive on a location or not. Santan and

Bougainvillea are both plants that are sensitive to the changes in the environment. If these plants

would wilt or die after being planted on a certain location, we can most likely conclude that the

air around is polluted. PSHS-WVC and Brgy. Balabag, Pavia are two places where Santan and

Bougainvillea would tend to survive thus it is safe to say that the air around these places is not

polluted.

28

CHAPTER 5

SUMMARY, CONCLUSIONS AND RECOMMENDATIONS

This study sought to determine the air pollution tolerance index of three plant species

(Ixora coccinea, Swietenia macrophylla, and Bougainvillea spectabilis) commonly found in the

polluted and unpolluted areas of Iloilo City. This was done by determining the total chlorophyll

content (TCh), leaf extract pH, ascorbic acid content (AA), and relative leaf water content

(RWC). Plant species with APTI value that is less than 16 is considered sensitive and act as a

bioindicator of air pollution; APTI value within 17 to 30 is considered intermediate and greater

than 30 is tolerant to air pollution (Liu and Ding, 2008).

A. Summary

The findings of this study are summarized as follows:

1. Bougainvillea and Santan are considered to be sensitive to air pollution because

the APTI values of these plants are less than 16. The APTI values of

Bougainvillea and Santan from PSHSWV are 12.94 and 13.65, respectively.

While the APTI values of Bougainvillea and Santan from Barangay Balabag,

Pavia, Iloilo are 7.18 and 21.72. The APTI values of Bougainvillea and Santan

from the two locations are statistically significant which proves that both

Bougainvillea and Santan are sensitive to air pollution and can act as bioindicator.

2. Mahogany is tolerant to air pollution and it cannot act as bioindicator to air

pollution. The APTI value of Mahogany from PSHSWV is 75.46 and the APTI

value of Mahogany from Barangay Balabag, Pavia, Iloilo is 73.68. These values

are statistically insignificant which proves that Mahogany is tolerant to air

pollution.

B. Conclusions

The air pollution tolerance index of Bougainvillea and Santan shows that it is

sensitive to air pollution while the air pollution tolerance index of Mahogany indicates

that it is tolerant to air pollution. Plant species that are found to be sensitive can act as

29

bioindicator to air pollution and plant species that are not sensitive to air pollution are

highly discourage to be used as a bioindicator.

C. Recommendations

Future researchers on air pollution tolerance index are recommended to find the

tolerance index of other plant species that are endemic in Iloilo City like Ipil-ipil, Banana,

Mango and Coconut. To acquire a further result, the plant species must be taken from a

more polluted area where it is more populated, urbanized, and industrialized. Researchers

may consult at the Department of Environment and Natural Resources for the assessment

handbook for polluted area.

Furthermore, researchers must try to determine the air pollution tolerance index

using multiple methods of measuring the four parameters: total chlorophyll content,

relative leaf water content, leaf extract pH and ascorbic acid content.

30

LITERATURE CITED

Brunekreef B and Holgate ST. 2002. Air pollution and health. 360: 1233-1242.

Enete IC and Ogbonna CE. 2012. Evaluation of Air Pollution Tolerance Index (APTI) Of Some Selected Ornamental Shrubs in Enugu City, Nigeria. IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT). 1(2):22-25.

Jyothi SJ and Jaya DS. 2010. Evaluation of air pollution tolerance index of selected plant species along roadsides in Thiruvananthapuram, Kerala. Journal of Environmental Biology. 31: 379-386.

Liu YJ and Ding H. 2008. Variation in Air Pollution Tolerance Index of Plants Near a Steel Factory: Implications for Landscape-Plant Species Selection for Industrial Areas. Wseas Trans. Environ. Dev. 4: 24-32.

Pati P and Patra PK. 2012. Benthic Foraminiferal Responses to Coastal Pollution: A Review. International Journal of Geology, Earth and Environmental Sciences. 2(1):42-56.

Seyyednjad SM, Majdian K, Koochak H and Niknejad M. 2011. Air Pollution Tolerance Indices of Some Plants Around Industrial Zone in South of Iran. Asian Journal of Biological Sciences. 4(3): 300-305.

Singh SK and Verma A. 2007. Phytoremediation of Air Pollutants: A Review. In: Environmental Bioremediation Technology, Singh SN and RD Tripathi (Eds.). Springer, Berlin Heidelberg. 293-314.

Stuartxchange. 2011. Mahogany. Available: http://www.stuartxchange.org/Mahogany. html via the INTERNET. Accessed 2012 September 15.

Stuartxchange. 2012. Bogambilya. Available: http://www.stuartxchange.org/Bogambilya. html via the INTERNET. Accessed 2012 September 15.

Stuartxchange. 2012. Santan. Available: http://www.stuartxchange.org/Santan.html via the INTERNET. Accesed 2012 September 15.

Thomas MD. 1963. Effects of Air Pollution on Plants. 233-278.

University of Canterbury. Determination of Vitamin C Concentration by Titration. Available: http://www.outreach.canterbury.ac.nz/chemistry/documents/vitaminc_ iodine.pdf via the INTERNET. Accessed 2012 September 20.

31

APPENDIX ARAW DATA

Actual Data

Relative Leaf Water Content (RWC):PSHSWVC

Fresh Weight Dry Weight Turgid Weight


1 1.01 0.99 1.35

2 0.87 0.70 1.10

3 1.07 1.03 1.29

Mahogany

(Swietenia macrophylla)

1 1.67 1.42 2.05

2 3.71 2.13 3.41

3 1.56 1.33 2.11

Bougainvillea

(Bougainvillea spectabilis)

1 0.73 0.70 1.01

2 0.62 0.57 0.91

3 0.88 0.83 1.04

PAVIA

Fresh Weight Dry Weight Turgid Weight


1 0.76 0.60 0.99

2 0.99 0.91 1.33

3 0.91 0.71 1.23

Mahogany


1 1.06 0.92 1.45

2 2.18 1.80 2.82

3 1.85 1.53 2.38

Bougainvillea


1 1.88 1.77 2.38

2 1.72 1.67 2.27

3 1.80 0.93 2.38

Relative Leaf Water Content for Each Plant:

32

PSHSWVC 1 2 3 Average

Ixora coccinea 5.56 4.25 15.38 8.40

Swietenia macrophylla 39.68 69.30 29.49 46.16

Bougainvillea spectabilis 9.68 14.71 31.25 18.55

PAVIA 1 2 3 RWC

Ixora coccinea 41.03 19.05 38.46 32.85



For Total Chlorophyll Content (T):PSHSWVC 645 663 CT TCh

Santan

(Ixora coccinea)

1 0.102 0.204 3.70 0.34

2 0.088 0.186 3.27 0.47

3 0.090 0.187 3.32 0.38

Mahogany


1 0.180 0.420 7.00 0.50

2 0.203 0.461 7.80 0.55

3 0.202 0.439 7.60 0.54

Bougainvillea


1 0.329 0.740 12.58 1.20

2 0.326 0.727 12.42 1.18

3 0.327 0.737 12.52 1.19

PAVIA 645 663 CT TCh

Santan

(Ixora coccinea)

1 0.157 0.176 4.58 0.38

2 0.199 0.404 7.26 0.60

3 0.161 0.280 5.50 0.46

Mahogany


1 0.111 0.199 3.84 0.32

2 0.141 0.269 5.01 0.52

3 0.105 0.189 3.64 0.31

Bougainvillea


1 0.409 1.000 16.28 1.29

2 0.436 1.029 17.06 1.51

3 0.489 1.071 18.47 1.46

33

Average:

PSHSWVC 645 663 CT TCh

Ixora coccinea 0.093 0.192 3.43 0.40



PAVIA 645 663 CT TCh

Ixora coccinea 0.172 0.287 5.78 0.48



Leaf Extract pH:PSHSWVC

pH

Ixora coccinea

1 5.1

2 5.3

3 5.6

Swietenia macrophylla

1 6.6

2 5.0

3 6.3

Bougainvillea spectabilis

1 7.3

2 6.1

3 6.0

PAVIApH

Ixora coccinea

1 6.2

2 6.1

3 6.1

Swietenia macrophylla 1 5.5

2 5.5

3 5.5

34


1 6.2

2 6.3

3 6.3

Average:PSHSWVC pH

Ixora coccinea 5.3

Swietenia macrophylla 6.0

Bougainvillea spectabilis 6.5

PAVIA pH

Ixora coccinea 6.1

Swietenia macrophylla 5.5

Bougainvillea spectabilis 6.3

Ascorbic Acid Content (AA):PSHSWVC

Titrant (mL)Ascorbic Acid

Content

Ixora coccinea

1 50 24.19

2 44.3 21.44

3 40 19.36


1 425 106.31

2 393.6 114.80

3 391.9 105.85


1 22.3 13.64

2 27.7 16.94

3 21 12.84

PAVIATitrant (mL)

Ascorbic Acid Content

Ixora coccinea 1 50 29.75

2 47 27.97

35

3 43 25.59


1 425 131.78

2 359.6 111.49

3 366.4 113.59


1 16 4.93

2 22 6.78

3 16.6 5.11

Average:PSHSWVC Titrant AA

Ixora coccinea 44.77 21.66

Swietenia macrophylla 403.50 108.99

Bougainvillea spectabilis 23.67 14.47

PAVIA Titrant AA

Ixora coccinea 46.67 27.77

Swietenia macrophylla 383.67 118.95

Bougainvillea spectabilis 18.20 5.61

Air Pollution Tolerance Index (APTI):PSHSWVC Relative

Leaf Water Content (RWC)


Leaf Extract pH

Ascorbic Acid

Content (AA)

APTI

Ixora coccinea

1 5.56 0.34 5.1 24.19 13.72

2 4.25 0.47 5.3 21.44 12.80

3 15.38 0.38 5.6 19.36 13.12

Swietenia

macrophylla

1 39.68 0.50 6.6 106.31 79.45

2 69.30 0.55 5.0 114.80 70.64

3 29.49 0.54 6.3 105.85 75.35

Bougainvillea

spectabilis

1 9.68 1.20 7.3 13.64 12.56

2 14.71 1.18 6.1 16.94 13.80

3 31.25 1.19 6.0 12.84 12.36

36

PAVIA Relative Leaf Water

Content (RWC)


Leaf Extract pH

Ascorbic Acid

Content (AA)

APTI

Ixora coccinea

1 41.03 0.38 6.2 29.75 23.80

2 19.05 0.60 6.1 27.97 20.67

3 38.46 0.46 6.1 25.59 20.74

Swietenia

macrophylla

1 26.42 0.32 5.5 131.78 79.73

2 37.25 0.52 5.5 111.49 71.29

3 37.65 0.31 5.5 113.59 69.87

Bougainvillea

spectabilis

1 18.03 1.29 6.2 4.93 5.50

2 8.33 1.51 6.3 6.78 6.09

3 60.00 1.46 6.3 5.11 9.96

Final DataPSHSWVC Relative

Leaf Water Content

(%)

Total Chlorophyll

Content (mg/g Dw)

Leaf Extract

pH

Ascorbic Acid

Content (mg/g Dw)

APTI

Santan

(Ixora coccinea)8.40 0.40 5.33 21.66 13.25

Mahogany


Bougainvillea


PAVIARelative Leaf Water Content (%)


Leaf Extract pH


APTI

Santan

(Ixora coccinea)32.85 0.48 6.16 27.77 21.72

Mahogany


Bougainvillea


37

APPENDIX B

ANOVA TABLES

Santan

Group Statistics

Study site N Mean Std. Deviation Std. Error Mean

APTI value Pavia 3 21.7367 1.78724 1.03186

PSHSWV 3 13.2133 .46705 .26965

Independent Samples TestLevene's Test for Equality of

Variances t-test for Equality of Means

95% Confidence Interval of the

Difference

F Sig. t dfSig. (2-tailed)

Mean Difference

Std. Error Difference Lower Upper

APTI value Equal variances assumed 8.017 .047 7.992 4 .001 8.52333 1.06652 5.56221 11.48446

Equal variances not assumed

7.992 2.272 .010 8.52333 1.06652 4.42259 12.62408

MahoganyGroup Statistics

Study site N Mean Std. Deviation Std. Error Mean

APTI value Pavia 3 73.6300 5.33025 3.07742

PSHSWV 3 75.1467 4.40852 2.54526



95% Confidence Interval of the Difference


Mean Difference


APTI value

Equal variances assumed .356 .583 -.380 4 .723 -1.51667 3.99360 -12.60469 9.57136


-.380 3.864 .724 -1.51667 3.99360 -12.76032 9.72698

Bougainvillea

38

Group Statistics

Study site N Mean

Std. Deviation

Std. Error Mean

APTI value

Pavia 3 7.1833 2.42269 1.39874

PSHSWV

3 12.9067 .78009 .45038



95% Confidence Interval of the Difference


Mean Difference


APTI value

Equal variances assumed 5.867 .073 -3.895 4 .018 -5.72333 1.46946 -9.80322 -1.64345


-3.895 2.410 .044 -5.72333 1.46946 -11.11869 -.32798

39

APPENDIX C

PLATES

Plate 1: Preparation of leaf samples

Plate 2: Weighing of leaves for relative leaf water content

40

Plate 3: Immersing of leaves in water overnight for relative leaf water content.

Plate 4: Drying of leaves in an oven overnight for relative leaf water content.

41

Plate 5: Weighing of leaves for ascorbic acid content.

Plate 6: Blending of leaves for ascorbic acid content, leaf extract pH and total chlorophyll content.

42

Plate 7: Extraction of leaf extract for ascorbic acid content, leaf extract pH and total chlorophyll content.

Plate 8: Iodine solution as titrant for titration to determine ascorbic acid content.

43

Plate 9: Titration for ascorbic acid content determination.

Plate 10: Measurement of leaf extracts pH

44

Plate 11: Centrifugation of samples for total chlorophyll content.

Plate 12: Centrifugation of samples for total chlorophyll content.

45

Plate 13: Samples for total chlorophyll content.

Plate 14: Measurement of total chlorophyll content using spectrophotometer.

46

Plate 15: Measurement of total chlorophyll content using spectrophotometer.

BUDGET

ServicesItem Quantity

(sample)Price/qty

(Php/sample)Total Price (Php)

RWC 6 0.00 0.00TCh 6 0.00 0.00AA 6 0.00 0.00pH 6 0.00 0.00

Laboratory Set-Up / ApparatusItem Quantity (piece) Price/qty Total Price

100mL Beaker 1 Php 180.00 Php 180.00Small test tubes 2 Php 21.00 Php 42.00100mL Graduated Cylinder 1 Php 348.00 Php 348.00

TransportationItem Quantity Price/qty (Php/ride) Total Price (Php)

47

Family Car ≈ 10 liters Php 54.28/L Php 542.80

Other MaterialsItem Quantity Price/qty Total Price

Gloves 5 (pair) Php 18.00 Php 90.00Tissue 1 (roll) Php 14.25 Php 14.251L Distilled Water 4 (bottle) Php 16.10 Php 64.401.5L Distilled Water 2 (bottle) Php 35.00 Php 70.00Small zip lock 1 (box) Php 75.00 Php 75.00Big zip lock 2 (box) Php 150.00 Php 300.00

Total Expenses

AmountServices Php 0.00Laboratory Set-up/Apparatus

Php 570.00

Transportation Php 542.80Other Materials Php 613.65

Total Php 1726.45

Task October November December January February

Proposal DefensePreparation of MaterialsCollection of LeavesMeasurement of RWCMeasurement of pHMeasurement of TMeasurement of AACalculation of APTIRecording of Data

48

Interpretation of Data and AnalysisWriting Chapters 4 and 5Book Binding

GANTT CHART

49

evaluation of air pollution tolerance index of bougainvillea, santan and mahogany

Documents

outer valves fall

noted strongly dependent

axillary pannicles shorter

ph meter calibrated

photosynthetic carbon fixation

factors determining resistance

cell wall synthesis

thick outer valves