cape environmental science ia unit 1

A Study of four coastal ecosystems in trinidad

NAME: SHARANA MOHAMMEDSUBJECT: ENVIRONMENTAL SCIENCE I.A. UNIT 1

SCHOOL: PRINCES TOWN WEST SECONDARY YEAR: 2014 - 2015

Table of Contents

Acknowledgements....................................................................................................................................1

Map of Trinidad........................................................................................................................................2

Introduction...............................................................................................................................................3

Scope.......................................................................................................................................................3

Purpose...................................................................................................................................................3

Objectives...............................................................................................................................................4

Literature Review......................................................................................................................................5

Methodology............................................................................................................................................12

Restate Project Objectives..................................................................................................................12

Activities and Data Collection............................................................................................................12

Laboratory Tests.................................................................................................................................13

Presentation and Analysis.......................................................................................................................15

Activities Pollution and Species Diversity..........................................................................................15

Laboratory Tests.................................................................................................................................18

Discussions of Findings...........................................................................................................................23

Conclusions..............................................................................................................................................25

Recommendations...................................................................................................................................26

Bibliography............................................................................................................................................27

Appendices...............................................................................................................................................28

Appendix 1...........................................................................................................................................28

Appendix 2...........................................................................................................................................29

Appendix 3...........................................................................................................................................32

Site Visits..................................................................................................................................................35

Laboratory Entries..................................................................................................................................47

Acknowledgements Completing this IA gave me a sense of fulfilment and I would like to thank the following people for their contributions. Firstly, I would like to thank God for giving me wisdom and the serenity needed in completing this project. My gratitude goes to my Environmental Science teacher for his guidance and assistance in completing this project diligently. Sincere thanks go to my parents for supporting me and giving me much needed help when necessary. Lastly, I pay gratitude to the authors of the various websites via the internet services which allowed me to obtain vital information needed for this Internal Assessment.

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Map of TrinidadMap 1: Showing the locations of all Site Visited.

1 Coastal Site A

3 Coastal Site C

2Coastal Site B 4 Coastal Site D

2

C

D

B

A

Introduction

An ecosystem comprises abiotic and biotic components as well as their interactions in the community. Ecosystems are defined according to their unique climate. Due to this, they are divided into different types, including – forest, grassland, desert, tundra, mountain, marine and aquatic ecosystems. However, in Trinidad, the main ecosystems present are forest, grassland, and mountain, marine and aquatic ecosystems.

Additionally, the main and most important type of ecosystem present in Trinidad is the coastal ecosystem. A coastal ecosystem is a combination of various ecosystems. It is defined as the area whereby the land meets the ocean, encompassing the shoreline ecosystems as well as the adjacent aquatic waters. Coastal ecosystems are a natural resource and are important in many islands, including Trinidad because they provide a range of goods and services that are integral to the sustainable development of these islands. These services include transportation and shipping via the ports, fishing as a source of food and, recreation. Furthermore, in Trinidad, the north eastern, eastern and south eastern coastal zones are essential as they form habitats for various species of plants and animals. These areas also provide a breeding ground for the endangered leather back turtles.

This study focuses mainly on four coastal ecosystems in Trinidad. In order for these areas to remain unambiguous, pseudo names were given to them. They are – Coastal ecosystem A, Coastal ecosystem B, Coastal ecosystem C and Coastal ecosystem D.

Scope

This study is focused on four coastal ecosystems, located in different areas in Trinidad. This is done to recognize the variations in these coastal ecosystems so a comparison among them can be made as it pertains to the anthropogenic impact on the environment.

Purpose

Coastal ecosystems play an important role in Trinidad. They provide sustenance to many communities in Trinidad and Tobago as well as host many habitats for various species of plants and animals. It is crucial that these areas be protected as coastal ecosystems play an important role in the cycling of nutrients and flora for rich biodiversity in our country. Coastal ecosystems provide a natural balance of life. As such, the purpose of this study is to recognize the services of four coastal ecosystems and to investigate and compare the anthropogenic impacts of each of these coastal ecosystems in Trinidad.

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Objectives

1. To investigate the biodiversity of four coastal ecosystems in Trinidad

2. To assess, identify and compare the various anthropogenic impacts of each site

3. To determine the biological oxygen demand (BOD) and determine if the levels are

comparable to unpolluted coastal zones. Other physicochemical parameters that maybe

helpful include :

a. Temperature

b. pH

c. Turbidity

d. Total Solids

e. Total Phosphates

f. Nitrates

g. Alkalinity

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Literature ReviewBiodiversity is the variety of species in an ecosystem, biome, or the entire planet. It is important for ecosystems to be stable because stability in ecosystems aid in preventing the ecosystem from being affected in the event of a disturbance and also helps in making the ecosystem resilient to change. Therefore, to make an ecosystem stable, there must be an equal and vast number of species. As such, the more diverse the species in an ecosystem are, the more stable the ecosystem will be. (Cleland, 2011) Coastal ecosystems provide many services to man and habitats for various plants and animals. Therefore, a rich biodiversity of a coastal ecosystem is necessary to preserve its stability and integrity.

The biodiversity in an ecosystem must be measured in order to obtain a knowledge of the different species which make up the ecosystem. To measure the biodiversity, many sampling methods are present in the literature. The different sampling methods are – random sampling, systematic sampling, stratified sampling and capture-mark-release. (Ecological Sampling Methods , 2000) From the literature many of the sampling methods used for biodiversity in coastal ecosystems were systematic, while other researchers used random and stratified. However, Richard Coe, an employee at the World Agroforestry Centre, indicated that these will not provide a rich comparison of the biodiversity in the area and recommended that a systematic method will provide a much better result. (Coe, 2008)

This study focuses on four main coastal ecosystems – A, B, C and D. Coastal ecosystem A is located on the South Eastern part of Trinidad and has a population of approximately 2300 persons. In the community where this ecosystem is found, the natural resources are oil and gas, with 20 percent of its workforce employed in the energy industry, while its human resources are agriculture and fishing, with 25 percent employed in agriculture and 30 percent in fishing. In the community, there is also a health centre, a primary and secondary school and two recreation grounds for use in the community. (Khan, 2010)

Coastal ecosystem B is located on the Eastern side of Trinidad and is considered one of the largest villages in Trinidad. The village has a population of 48,000 persons. (Mayaro Rio Claro Regional Corporation, 2011) In the community where this ecosystem is found, the natural resources are oil and gas, with 35 percent of its workforce employed in the energy industry, while its human resources are agriculture, fishing and commerce, with 25 percent employed in agriculture and 30 percent in fishing. (MEP Publishers (Media & Editorial Projects Ltd) , 2013) In the community, there is also a health centre, a primary and secondary school, banks, a market, several shopping centres and four recreation grounds for use in the community.

Coastal ecosystem C is a small village which is located on the South Western Peninsula of Trinidad and has a population of 1,107 persons. In the community where this ecosystem is found, the natural resources are oil and gas, with 55 percent of its workforce employed in the energy industry, while its human resources are agriculture, fishing and commerce, with 30 percent employed in agriculture and 40 percent in fishing. In the community, there are three primary

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schools, and a secondary school and a community centre. (New community centre to be opened in Vessigny, 2014)

Coastal ecosystem D is located on the North Western Peninsula of Trinidad and has a population of 885 persons. The community where this ecosystem is found was originally used for agriculture and the land-use transitioned from sugar cultivation to cocoa to citrus, then to coffee and nutmeg. It was also used as an American military base during the period of World War 1. Currently, this community is used mainly as a tourist attraction with attractions such as a beach, a military museum and a national park. (Things To Do In Chaguaramas Bay Peninsula, n.d.) About 65% of its population employed in the tourism industry.

Water, via its physical, chemical and biological characteristics, plays an important role in the sustenance of the earth’s biotic components. However, over the years, man has had a huge impact on water quality via their unscrupulous practices of misusing the areas in and around water bodies for unethical activities. These include the discharge of domestic, municipal, industrial and other factors like religious offerings, recreational and constructional activities in coastal areas.

As a result of these impacts, the physicochemical characteristics of water are greatly affected since these impacts cause alterations to the natural balance of water due to the foreign substances injected into it. As such, water quality tests are done to quantitatively determine the anthropogenic impacts on the environment. (Singh , Sanamacha Meetei, & Bijen Meitei, 2012)

These test were –

a. Biochemical Oxygen Demand

b. Temperature

c. pH

d. Turbidity

e. Nitrates

f. Total Solids

g. Total Phosphates

h. Alkalinity

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Biological Oxygen Demand Dissolved oxygen is the form of oxygen accessible to aquatic organisms. Oxygen is vital to aquatic species as they use it to build energy through respiration. In a “healthy” body of water, oxygen is replenished quicker than it’s used by aquatic organisms. However, in some bodies of water, aerobic bacteria decompose such a vast volume of organic material, that oxygen is depleted from the water faster than it can be replaced. The resulting decrease in dissolved oxygen is known as the Biochemical Oxygen Demand (BOD).

Vital nutrients, for example nitrates and phosphates, which stimulate aquatic plant and algae growth, are released via decomposition. If the load of decomposing organic material is excessive, dissolved oxygen levels can be critically diminished. In a body of water with substantial amounts of decaying organic material, the dissolved oxygen levels may decline by 90%, this would represent a high BOD. This can be widely impacted by human pollution and therefore needs to be monitored. Table 1 shows the effect of various levels of BOD in the water.

Table 1 – The interpretation of BOD Levels

BOD Level (mg/L) Status1-2 Clean water with little organic waste.3-5 Moderately clean water with some organic waste.6-9 Lots of organic material and bacteria.

10-20 Very poor water quality. Large amounts of organic material in the water common to treated sewage.

20-100 Untreated sewage or high levels of effluents from industries or high levels of erosion.

>100 Extreme conditions. Siltation and stationary water.

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Temperature Thermal pollution, caused by human activities, is one factor that can affect water temperature. Water temperatures outside the standard range for a beach can cause harm to the aquatic organisms that live there. Due to this reason, the temperature of the water over a section of a beach is measured. Table 2 shows the cause and effect relationship with changes in temperature.

Table 2 – The causes and effects of changes in water temperature

Changes in Water TemperatureCauses Effects

- Air Temperature - Solubility of dissolved oxygen- Amount of shade - Rate of plant growth- Soil erosion from increasing turbidity - Metabolic rate of organisms- Thermal pollution from human

activities- Resistance in organisms

pH Aquatic organisms are extremely fragile to the pH of their environment. If the pH of the environment in which these organisms live is not between their optimum ranges, these species may become endangered as they won’t be able to survive and reproduce. Therefore, the measure of the pH of a body of water is very important as an indication of water quality. The factors that affect pH can be seen in Table 3.

Table 3 – Factors that affect pH levels

Factors Affecting pH Levels- Acidic rainfall- Algal blooms- Level of hard-water minerals- Releases from industrial

processes- Carbonic acid from

respiration or decomposition- Oxidation of sulphides in

sediments

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Turbidity The measure of water’s lack of clarity is known as Turbidity. Water with high turbidity is cloudy, whereas water with low turbidity is clear. A high turbidity is as a result of light reflecting off of particles in the water thus resulting in the cloudiness. As such, the more particles in the water, the higher the turbidity. Also, the rate of photosynthesis will decrease due to this because a high turbidity will decrease the amount of sunlight that’s able to penetrate the water. Additionally, reduced clarity causes the water to be less aesthetically appealing. Even though this isn’t directly detrimental, it is definitely unacceptable for many water uses. When the water is cloudy, sunlight will warm it more efficiently because the suspended particles in the water absorb the sunlight, warming the surrounding water. This may lead to many issues linked to increased temperature levels. Therefore, the Turbidity of a beach needs to be measured to guarantee it doesn’t produce unwanted effects as shown in Table 4.

Table 4 – The sources and effects of turbidity in coastal waters

Change in Water TemperatureSource Effect

- Soil erosion – silt & clay - Reduces water clarity- Urban runoff - Aesthetically displeasing- Industrial waste – sewage treatment effluent

particulates- Decreases photosynthetic rate

- Abundant bottom dwellers – stirring up sediments - Increases water temperature- Organics – microorganisms & decaying plants &

animals

Total Solids A measure of all the suspended, colloidal, and dissolved solids in a sample of water is known as Total solids, TS. This includes dissolved salts for example, sodium chloride, NaCl, and solid particles such as silt and plankton. Total solids have the same impacts as Turbidity and can be described in Table 4.

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Total Phosphates Phosphorus is a vital nutrient for all aquatic plants and algae. However, only a minute amount is necessary, therefore, an excess can easily occur. An excess amount is classified as a pollutant as it results in eutrophication, the condition whereby there’s an excessive richness in nutrients, such as phosphorous, which results in increased plant and algal growth. Eutrophication can lower the levels of dissolved oxygen in the water and can make the water uninhabitable by many aquatic organisms. Phosphorus is frequently the limiting factor that controls the extent of eutrophication that occurs. Table 5 shows the sources and effects of phosphate levels in water.

Table 5 – The sources and effects of phosphate levels in water

Phosphate levelsSource Effect

- Human and animals wastes - High levels of – eutrophication, increased algal bloom, increased BOD, decreased DO

- Industrial wastes - Low levels – limiting factor in plant and algal growth

- Agricultural runoff- Human disturbance of land

Nitrates Nitrates are an essential source of nitrogen required by plants and animals to synthesize amino acids and proteins. Nitrate pollution, caused by fertilizer runoff and concentration of livestock in feedlots, has become a major ecological issue in some agricultural areas. Table 6 shows the sources of nitrate ions in surface water.

Table 6 – Sources of Nitrate Ions

Sources of Nitrate Ions- Agriculture runoff- Urban runoff- Animal feedlots and barnyards- Municipal and industrial wastewater- Automobile and industrial emissions- Decomposition of plants and animals

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Alkalinity A measure of how much acid water can neutralize is known as the Alkalinity of water. Alkalinity acts as a buffer, protecting water and its life forms from immediate changes in pH. This ability to neutralize acid, is especially essential in regions affected by acid rain, or industries that contribute to surface acidity of surface water. Table 7 shows the effect of alkalinity to surface water.

Table 7 – The effects of alkalinity levels

Effects of Alkalinity Levels- Buffers water against sudden changes in

pH- Protects aquatic organisms from sudden

changes in pH

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Methodology

Restate Project Objectives




comparable to unpolluted coastal zones. Other physicochemical parameters that maybe

helpful include :

a. Temperature

b. pH

c. Turbidity

d. Nitrates

e. Total Solids

f. Total Phosphates

g. Alkalinity

Activities and Data Collection

For this study, four coastal ecosystems were visited at the North, South, East and West parts of Trinidad. The class was divided into three groups which consisted of three students each. I belonged to Group 1 and the other two members of my group were – Allison Cardinez and Amara Khan. Each coastal ecosystem was also divided into three parts and each group was assigned to a particular site to assess. Part of this assessment was done in the form of an informal site survey whereby the anthropogenic impacts on the environment was determined by the level of visual pollution seen and also in terms of the alterations made on the environment by man, for example, in the form of construction.

The other part of the assessment was done in the form of Systematic Sampling as it was deemed to be most appropriate for this study. Systematic sampling entails taking samples at fixed intervals and this involves the use of either a line or belt transect. However, the belt transect

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method was used as it was more suitable for this study because it gave information on species abundance.

At each site, each of the three groups placed quadrats in a linear pattern, forming a continuous “belt”, recording the percentage of plant and animal species found in each quadrat along with the level of pollution found in each. This was done continuously until the least number of quadrat readings totalled to be 20. The groups then pooled their results together in order to find the total species diversity for each site.

Lastly, water samples were collected from each site and water quality tests were done on these samples. This is because, over the years, man has had a huge impact on water quality via their unscrupulous practices of misusing the areas in and around water bodies for unethical activities. As a result of these impacts, the physicochemical characteristics of water are greatly affected since these impacts cause alterations to the natural balance of water due to the foreign substances injected into it. As such, water quality tests were done to quantitatively determine the anthropogenic impacts on the environment.

Laboratory Tests

Water quality tests will give information about the “health” of the coastal waters. By testing water over a period of time, the alterations in the quality of the water can be seen. However, due to the limitation of time with the borrowed equipment, reagents and time only one set of tests could have been performed for each site visited. The parameters that were tested in this project included temperature, pH, turbidity, nitrates, phosphates, BOD5 and Alkalinity. A qualitative visual assessment of the aquatic system was also carried out.

A LabQuest2 water quality testing package, provided by the University of Trinidad and Tobago, Agricultural and Food Technology Department, was used to test the water quality parameters. The LabQuest2 water quality testing kit included probes for testing water, temperature, pH, turbidity, nitrates, phosphates, BOD and alkalinity.

The LabQuest2 is a portable, hand held device, to which various probes are used to determine the properties of the sampled water. At each site, each group of the three groups collected four (4) water samples using plastic bottles from the water of the beach. These bottles were labelled A to D. In addition to the four water samples taken, another five (5) samples were taken using glass bottles to test for BOD5, these bottles were labelled E1 to E5.

The water samples were collected by completely submerging the bottles into the water and allowing water to fill up to the “mouth” of the bottle. After this, the lid was quickly fastened on the bottle, while it was still under water. The bottles were then packaged and transported to the laboratory. This method of sampling was done for all the coastal sites visited. Each sample set was then brought to the laboratory for testing using the LabQuest2 to obtain the following readings of –

1. Biochemical Oxygen Demand – Bottles E1 to E5 which were stored in ice and wrapped in foil were used for this. The dissolved oxygen levels present on the initial day and at the end of the five day period were measured using the Dissolved Oxygen Sensor. The difference and average was then determined as the BOD5.

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2. Temperature. – The Stainless Steel Temperature Probe was placed into bottle “A” and after the temperature stabilized on the interface, the reading was recorded.

3. pH – The pH Sensor Probe was placed into bottle “A” and swirled until a reading of the pH was stabilised on the interface and the reading was recorded.

4. Nitrates – The nitrate-ion concentration in the water sample from bottle “A”, in mg/L NO3, was measured by placing the electrode from the Nitrate Ion-Selective Electrode into the bottle. The reading was then recorded.

5. Turbidity – The Turbidity in NTU was determined using the Turbidity Sensor. Water from sample bottle “A” was poured into a cuvette and placed into the Turbidity Sensor. The reading was then recorded.

6. Total Solids – A precise amount of water from Bottle “B” was measured and placed into a clean, dried and weighed beaker. A drying oven was then used to evaporate the water and the beaker was reweighed. The difference between the final and initial mass the total solids was calculated. Calculations were also made to convert the mass to mg/L total solids.

7. Total Phosphates – A colorimeter was used to create a 4-point standard curve of phosphate absorbance vs concentration, by using a set of four phosphate standards. The water sample from bottle “C” was then poured into the cuvette and placed into the colorimeter to determine its absorbance. The concentration of the total phosphates was deduced from the graph, using the absorbance of the water sample.

8. Alkalinity – Alkalinity of the water samples was determined by titrating 0.001M sulphuric acid against the water sample in Bottle “D”, using a methyl orange indicator to determine the end point of the reaction. At the end point of the reaction, the alkalinity was determined using the stoichiometric ratio between sulphuric acid and calcium carbonate.

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Presentation and Analysis

Activities Pollution and Species Diversity

Graph 1 –

Paper Bottles Plastics Oil SpillsRecreational Recreational Recreational Industrial

0

10

20

30

40

Graph showing the average amount and type of pollution seen at each site

ABCD

Pollution Type

Ave

rage

Num

ber

The graph above indicates that in visible pollution, there is a predominance of bottles and paper, with Site B being polluted mainly by bottles.

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Graph 2 –

Group 1 OverAll SD

Amphibians and Aquatic

Grass and Ferns

Herbs Insects and Arachnids

Sedge, Tree and Vine

- 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00

10.00

Graph showing Group 1 reults for the average species diversity of each site

A B C D

Species Type

Ave

rage

Num

ber

The above graph shows that site B had the highest species diversity which was 9.43 whereas site D had the lowest which was 5.60.

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Graph 3 –

A B C D 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 9.50

Graph showing difference between group 1 overall species diversity and mean overall species diversity

Group 1 Overall Species Diversity Mean Overall Species Diversity

Coastal Site

Ave

rage

Num

ber

The graph above indicates that Site B, despite having the highest level of pollution, had the greatest species diversity of approximately 9.5 as compared to site D with the lowest species diversity of approximately 6.

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Laboratory Tests

Graph 1 –

A B C D

02468

101214

Graph showing the Nitrate, Phosphate and pH level at each site

Nitrates (mg/L)Total Phosphates Concen-tration (mg/L)pH

Coastal Site

The graph above indicates that there were fluctuations among the levels of Nitrates and Phosphates present at the four coastal sites; coastal site B had the highest level of Nitrates and Phosphates. Nitrates are acidic in nature whereas phosphates are alkali in nature. As such, the presence of both nitrates and phosphates in the water would keep the pH within a steady range. This is justified by the graph as it is seen that the pH values of the four visited coastal sites were fairly similar with values ranging between 5.73 and 6.84, which is a habitable pH for aquatic organisms.

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Graph 2 –

A

B

C

D

0 10 20 30 40 50 60 70 80 90 100

Graph showing the BOD(mg/L) and Total Solids(mg/L) level at each site

Total Solids(mg/L) BOD(mg/L)

Coa

stal

Site

From the graph above it is observed that as the level of Total Solids increases, the level of

Biological Oxygen Demand also increases. This is due to the dark appearance of the large

amounts of solid particles in water which attracts heat from the sun thus causing an increase in

water temperature. As such, water loses its ability to hold dissolved oxygen which therefore

results in an increase in the Biological Oxygen Demand.

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Graph 3 –

A B C D010203040506070

Graph showing the Nitrate and Alkalinity level at each site

Nitrates(mg/L)Alkalinity(mg/L)

Coastal Site

The above graph shows that when the Alkalinity level in water is high, the Nitrate level is low. This is because both Nitrates and Alkalinity are interrelated since Nitrates are acidic in nature whilst Alkalinity is defined as the measure of the amount of acid in which water can neutralize. Thus, when the Alkalinity level in water is high, the Nitrate level will be low.

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Graph 4 –

A B C D02468

101214

Graph showing the Biological Oxygen Demand, Ni-trate and Phosphate level at each site

BOD(mg/L) Nitrates(mg/L) Phosphates(mg/L)

Coastal Site

The graph above indicates that when there is a high level of Nitrates and Phosphates present in water, the level of Biological Oxygen Demand increases. The reason for this is that Nitrates and Phosphates are interrelated to the Biological Oxygen Demand. As the level of decomposing organic matter such as nitrates and phosphates increases, the level of dissolved oxygen decreases thus resulting in an increase in the Biological Oxygen Demand in water.

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Graph 5 –

A

B

C

D

0 5 10 15 20 25 30

Graph showing the BOD(mg/L) level and Temperature(0C) level at each site

Temperature/°C BOD(mg/L)

Coas

tal S

ite

From the graph above it is seen that as the Temperature increases, the level of Biological Oxygen

Demand also increases. This is because increased water temperatures speeds up bacterial

decomposition which results in higher BOD levels.

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Discussions of Findings Pollution disrupts natural ecosystems and as such, it is expected that sites with low levels of pollution would have a high species diversity. However, this is in contrast to the data collected and observations made at the four sites A, B, C and D visited. It was observed that site B had the highest level of pollution while site D had the lowest. However, when calculated, the mean species diversity of sites A, B, C and D were 8.41, 9.33, 8.57 and 5.54 respectively. It is noted that the site which had the highest level of pollution, site B, had the highest species diversity, whereas the site which had the lowest level of pollution, site D, had the lowest species diversity. This may be because site D, in contrast to sites A, B and C, is also a mountainous ecosystem and as such, few species live there. However, the main reason is due to the level of development at site D, which is used mainly as a tourist attraction. The natural ecosystem was modified by the construction of buildings and recreational facilities, thus affecting the natural habitat and resulting in a low species diversity. The effect of pollution would therefore further decrease the pre-existing small species diversity at this site. In contrast, there was little visual modifications made to site B and as such, the natural habitat of these species was preserved which resulted in the species diversity being high. The effect of pollution would have decreased this species diversity however since it was originally high, it remained the site with the highest species diversity. Also, it was observed that the ecosystem at sites A and C was not majorly affected by changes in infrastructure, thus their species diversity remained at a moderate average. However, pollution would have caused a decrease in this average.

From the observations made, it was seen that the water of the four coastal sites visited was not clear in appearance. The colour of the water of both sites A and C was light brown, site B was brown in colour and site D had a cloudy appearance. This was due to the varying levels of turbidity in the water. Turbidity is a measure of water’s lack of clarity and can thus be interrelated to the level of Total Solids present in water since a high level of Total Solids present would cause water to lose its clarity and thus results in a high Turbidity level.

Furthermore, from the research done, it is noted that different forms of agricultural processes take place at each site. As such, there may have been use of Nitrate and Phosphate fertilizers at each site. The presence of Nitrates and Phosphates in water would contribute to the level of Total Solids present and would thus affect the Turbidity of water, which therefore accounts for the colour of the water seen. However, the level of Nitrates present would be affected by the level of Alkalinity of the water. This is because the alkalinity of water is a measure of how much acid it can neutralize. When the Alkalinity level is high, the Nitrate level would therefore be low as water is able to neutralize nitrates which are acidic in nature. From the results obtained, it was seen that each coastal site had a high level of Alkalinity

Apart from this, the presence of Nitrates, which are acidic in nature, and Phosphates, which are basic in nature, would also affect the pH of water. The pH of each site ranged between 5.73 and 6.84. On the pH scale, a pH of 7 is neutral, below 7 is acidic and above 7 is basic. As such, these pHs would be considered relatively acidic. Since the pH of the sites wasn’t extremely acidic, it can be established that the existence of both Nitrates and Phosphates in water kept the pH at a relative balance.

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Also, the results of the tests indicated that each coastal site visited had a relatively low level of Biological Oxygen Demand. Aquatic organisms obtain oxygen in the form of dissolved oxygen. When aerobic bacteria decompose a vast volume of organic material such that oxygen is depleted faster than it can be replaced, the resulting decrease in dissolved oxygen is known as the Biological Oxygen Demand. The level of BOD in water would be affected by the level of Total Solids since Total Solids consist of solid particles which may have a dark appearance. The dark appearance of the large amounts of solid particles in water will attract heat from the sun and cause the temperature of the water to increase. This therefore causes water loses its ability to hold dissolved oxygen which therefore results in an increase in the Biological Oxygen Demand.

In addition to this, Total Solids may consist of substances such as Nitrates and Phosphates which cause the growth of algae. This can be interrelated to the temperature of water since an increase in water temperature causes an increase in the rate of photosynthesis by algae and other plant life. This therefore results in faster plant growth but would also cause plants to die faster. When plants die, they are decomposed by bacteria. In order for decomposition to take place, bacteria requires a large supply of oxygen which thus results in a high BOD. As such, when the level of Total Solids and Temperature increases, the Biological Oxygen Demand increases.

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Conclusions Within the limits of experimental errors, from the various observations made throughout this Internal Assessment and tests carried out at all four sites, Coastal Site B had the highest level of water pollution, since the physicochemical parameters which were tested for were greatest at this site, and also, the highest level of visual pollution. As such, from the four coastal sites visited, site B was affected by anthropogenic impacts the most. However, this site had the highest species diversity which was 9.33. In contrast, the tested physicochemical parameters were lowest at Coastal Site D; this site had the least water pollution and also had the lowest level of visual pollution seen. As such, this site was therefore was least affected by anthropogenic activities, however the species diversity at this site was the lowest, being that of 5.54. Coastal Site C also had a relatively high level of water pollution but a low level of visual pollution as compared to Coastal Site A. This therefore resulted in the species diversity at site A and C to be 8.41 and 8.57 respectively.

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Recommendations

- There should be a decrease in the amount of Nitrate and Phosphate based fertilizers used

at the four coastal sites

- Laws should be implemented to prevent the indiscriminate dumping of waste material

near the coastal zones

- The quality of water at all sites should be monitored frequently so that the ecosystems

can have an optimum environment for growth and maintenance.

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Bibliography

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Ecological Sampling Methods . (2000). Retrieved from Offwell Woodland & Wildlife Trust: http://www.countrysideinfo.co.uk/howto.htm

Khan, A. (2010, August 6). Official opening of Guayaguayare Community Centre. Retrieved from The Government Information Service Limited (GISL): http://www.news.gov.tt/archive/index.php?news=4955

MEP Publishers (Media & Editorial Projects Ltd) . (2013, 10 22). Touring Trinidad: the East Coast. Retrieved from Discover Trinidad & Tobago Travel Guide: http://www.discovertnt.com/articles/Trinidad/Touring-Trinidad-pt-7-the-East-Coast/172/3/23#axzz3SW87jwev

New community centre to be opened in Vessigny. (2014). Retrieved from Ministry of Community Development: http://www.community.gov.tt/home/content/new-community-centre-be-opened-vessigny

Singh , A., Sanamacha Meetei, N., & Bijen Meitei, L. (2012). Seasonal Variation of Some Physico-Chemical Characteristics of Three Major Rivers in Imphal, Manipur: A Comparative Evaluation. Retrieved from Current World Environment: http://www.cwejournal.org/vol8no1/seasonal-variation-of-some-physico-chemical-characteristics-of-three-major-rivers-in-imphal-manipur-a-comparative-evaluation/

Things To Do In Chaguaramas Bay Peninsula. (n.d.). Retrieved from Discover TT: http://www.discover-tt.net/travel_and_tourism/things_do_chaguaramas_bay_peninsula.html

27

Appendices

Appendix 1

Table showing the overall visual pollution seen at each site

Total for average of 15 Quadrats 15m^2 by 3 groups Percentage Coverage)

Pollution Type Pollution A B C D

Recreational Paper 30 23 18 2

Recreational Bottles 12 34 10 3

Recreational Plastics 11 23 12 6

Industrial Oil Spills 23 6 24 0

28

Appendix 2

Table showing Group 1 results for the species diversity at each site

Total for average of 15 Quadrats 15m^2 by Group 1

Type Scientific Name

Common Name

A B C D A B C D

amphibian Eleutherodactylus johnstonei

Whistling Frog; Fluitkikker

2 2 1 - 2.00 1.31 -0.25 0.00

amphibian Scarthyla vigilans

Solano frog

- - - 2 0.00 0.00 0.00 2.00

aquatic Eichhornia crassipes

Water Hyacinth

2 2 - - 2.81 2.81 0.00 0.00

fern Adiantum raddianum

Fern 6 2 - - 32.81 2.00 0.00 0.00

grass Cyperus rotundus

Nut Grass 16 33 9 - 247.81 1072.31

63.75 0.00

grass Axonopus compressus

Savanna Grass, Carpet Grass, Flat Grass

75 64 100 - 5550.00

3968.75

9900.00

0.00

grass Brachiaria mutica

Paragrass 4 9 - - 10.31 67.81 0.00 0.00

grass Paspalum fasciculatum

Bull Grass, Bamboo Grass

14 7 6 - 168.75 42.00 27.31 0.00

grass Paspalum paniculatum

Galmarra Grass

- - - 14 0.00 0.00 0.00 182.00

grass Sporobolus indicus

Tapia, Drop Seed, Hay Grass

5 9 - - 22.31 72.00 0.00 0.00

grass Setaria poiretiana

Bristle grass

- - - 3 0.00 0.00 0.00 6.00

grass Rottboellia cochinchinensis

Sugarcane Weed

- - 8 - 0.00 0.00 56.00 0.00

grass Bambusa vulgaris

Bamboo - 1 - - 0.00 -0.19 0.00 0.00

herb Alternanthera ficoidea

Crab Weed

6 9 27 - 27.31 63.75 702.00 0.00

herb Amaranthus dubius

Bhagi 2 5 - - 2.00 22.31 0.00 0.00

herb Bidens pilosa Railway Daisy, Spanish Needle

- - - 6 0.00 0.00 0.00 27.31

herb Blechum brownei/

John Bush, Wild Hops

- - - 5 0.00 0.00 0.00 22.31

29

pyramidatumherb Caladium

bicolorWhite Eddoe

- - - - 0.00 0.00 0.00 0.00

herb Commelina diffusa

Water Grass

20 59 53 - 360.75 3363.75

2756.00

0.00

herb Drymaria cordata

Chick Weed

11 20 9 - 115.31 360.75 63.75 0.00

herb Emilia sonchifolia

Consumption Weed, Sow Thistle, Cupid Paint, Shaving Bush

- - - 9 0.00 0.00 0.00 63.75

herb Eryngium foetidum

Shadon Benny

- - 2 - 0.00 0.00 2.00 0.00

herb Euphorbia hirta Milk Weed, Spurge

- - - 3 0.00 0.00 0.00 6.00

herb Peperomia pellucida

Silver Bush, Ratta Tempa

- - - 11 0.00 0.00 0.00 104.81

herb Physalis angulata

Hog Weed - 2 - - 0.00 1.31 0.00 0.00

herb Sida acuta Ballier Savanne, Broom Weed

- - - 8 0.00 0.00 0.00 56.00

herb Spigelia anthelmia

Worm Bush, Pink Weed

- - 7 - 0.00 0.00 38.81 0.00

herb Tridax procumbens

Wild Daisy - 6 - 8 0.00 24.75 0.00 56.00

herb Parthenium hysterophorus

White Top - - - 1 0.00 0.00 0.00 0.00

insect Solenopsis geminata

Tropical Fire Ant

81 120 81 - 6399.75

14160.75

6399.75

0.00

insect Solenopsis invicta

Red Imported Fire Ant

- - - 108 0.00 0.00 0.00 11609.81

insect Tapinoma melanocephalum

Black-Headed Ant, Ghost Ant

39 36 21 16 1462.81

1242.31

430.31 247.81

insect Philornis downsi

Fly 2 - 8 - 0.75 0.00 59.81 0.00

insect Plutella xylostella

Diamond Back Moth

1 2 - - -0.25 0.75 0.00 0.00

insect Aleurothrixus woglumi

Citrus Black Fly

6 11 16 - 27.31 104.81 247.81 0.00

insect Cryptolaemus montrouzieri

Lady Bird Beetle

5 8 11 - 20.00 59.81 115.31 0.00

30

insect Family Hesperiidae

Skipper Butterfly

3 4 6 - 6.00 12.00 27.31 0.00

insect Consul fabius Tiger with Tails

1 1 2 - -0.19 0.31 1.31 0.00

insect Mestra hypermestra cana

Grey Handkerchief

2 2 2 - 0.75 2.00 2.81 0.00

insect Cryptotermes domesticus

Termite 20 31 22 42 380.00 899.75 472.81 1680.75

insect Aedes aegypti Tiger Mosquito

8 16 24 - 52.31 247.81 540.31 0.00

insect Paratrechina longicornis

Crazy Ant 60 80 100 86 3540.00

6320.00

9900.00

7310.00

Arachnid Marptusa Spp Spider 2 4 3 9 2.00 10.31 6.00 63.75

sedge Cyperus rotundus

Nut Grass 5 8 - - 22.31 59.81 0.00 0.00

tree Bambusavulgaris

Bamboo 2 1 - - 0.75 0.00 0.00 0.00

tree Syzygium cumini

Indian Blackberry/ Gulab Jamoon

- - - 1 0.00 0.00 0.00 -0.19

tree Roupala montana

Beef wood - - - 11 0.00 0.00 0.00 104.81

tree Acacia mangium

White Teak

- - - 1 0.00 0.00 0.00 0.00

vine Merremia umbellata

Hog Vine - - 8 6 0.00 0.00 56.00 27.31

vine Momordica charantia

Cerasee Bush

1 2 2 - -0.19 0.75 1.31 0.00

N 397.25 551.5 526 348 18456.31

32186.63

31870.25

21570.25

N(N-1) 157410.3125

303600.75

276150

120756

Species DiversityGroup 1 Overall SD

8.53 9.43 8.66 5.60

Amphibians & Aquatic

2.87 2.91 1.00 1.00

Grass and Ferns

2.37 2.93 1.48 1.45

Herbs 2.86 2.53 2.63 7.36

Insects and Arachnids

4.31 4.25 4.80 3.23


2.13 1.73 1.49 2.39

31

Appendix 3

Table showing the mean species diversity at each site

Total for average of 15 Quadrats 15m^2 by 3 groups

Type Scientific Name Common Name

A B C D A B C D

amphibian Eleutherodactylus johnstonei

Whistling Frog; Fluitkikker

8 7 2 0 56 42 2 0

amphibian Scarthyla vigilans Solano frog

0 0 0 8 0 0 0 56

aquatic Eichhornia crassipes

Water Hyacinth

9 9 0 0 72 72 0 0

fern Adiantum raddianum

Fern 25 8 0 0 600 56 0 0

grass Cyperus rotundus Nut Grass 65 133 34 0 4160 17556 1122 0

grass Axonopus compressus

Savanna Grass, Carpet Grass, Flat Grass

300 254 400 0 89700 64262 159600

0

grass Brachiaria mutica Paragrass 15 35 0 0 210 1190 0 0

grass Paspalum fasciculatum

Bull Grass, Bamboo Grass

54 28 23 0 2862 756 506 0

grass Paspalum paniculatum

Galmarra Grass

0 0 0 56 0 0 0 3080

grass Sporobolus indicus Tapia, Drop Seed, Hay Grass

21 36 0 0 420 1260 0 0

grass Setaria poiretiana Bristle grass

0 0 0 12 0 0 0 132

grass Rottboellia cochinchinensis

Sugarcane Weed

0 0 32 0 0 0 992 0

grass Bambusa vulgaris Bamboo 0 3 0 0 0 6 0 0

herb Alternanthera ficoidea

Crab Weed

23 34 108 0 506 1122 11556 0

herb Amaranthus dubius Bhagi 8 21 0 0 56 420 0 0

herb Bidens pilosa Railway Daisy, Spanish Needle

0 0 0 23 0 0 0 506

herb Blechum brownei/pyramidatum

John Bush, Wild Hops

0 0 0 21 0 0 0 420

herb Caladium bicolor White Eddoe

0 0 0 0 0 0 0 0

herb Commelina diffusa Water Grass

78 234 212 0 6006 54522 44732 0

32

herb Drymaria cordata Chick Weed

45 78 34 0 1980 6006 1122 0

herb Emilia sonchifolia Consumption Weed, Sow Thistle, Cupid Paint, Shaving Bush

0 0 0 34 0 0 0 1122

herb Eryngium foetidum Shadon Benny

0 0 8 0 0 0 56 0

herb Euphorbia hirta Milk Weed, Spurge

0 0 0 12 0 0 0 132

herb Peperomia pellucida

Silver Bush, Ratta Tempa

0 0 0 43 0 0 0 1806

herb Physalis angulata Hog Weed 0 7 0 0 0 42 0 0

herb Sida acuta Ballier Savanne, Broom Weed

0 0 0 32 0 0 0 992

herb Spigelia anthelmia Worm Bush, Pink Weed

0 0 27 0 0 0 702 0

herb Tridax procumbens Wild Daisy 0 22 0 32 0 462 0 992

herb Parthenium hysterophorus

White Top 0 0 0 4 0 0 0 12

insect Solenopsis geminata

Tropical Fire Ant

322 478 322 0 103362

228006

103362

0

insect Solenopsis invicta Red Imported Fire Ant

0 0 0 433 0 0 0 187056

insect Tapinoma melanocephalum

Black-Headed Ant, Ghost Ant

155 143 85 65 23870 20306 7140 4160

insect Philornis downsi Fly 6 0 33 0 30 0 1056 0

insect Plutella xylostella Diamond Back Moth

2 6 0 0 2 30 0 0

insect Aleurothrixus woglumi

Citrus Black Fly

23 43 65 0 506 1806 4160 0

insect Cryptolaemus montrouzieri

Lady Bird Beetle

20 33 45 0 380 1056 1980 0

insect Family Hesperiidae Skipper Butterfly

12 16 23 0 132 240 506 0

insect Consul fabius Tiger with Tails

3 5 7 0 6 20 42 0

insect Mestra hypermestra cana

Grey Handkerchief

6 8 9 0 30 56 72 0

insect Cryptotermes Termite 80 122 89 166 6320 14762 7832 27390

33

domesticusinsect Aedes aegypti Tiger

Mosquito31 65 95 0 930 4160 8930 0

insect Paratrechina longicornis

Crazy Ant 240 320 400 344 57360 102080

159600

117992

Arachnid Marptusa Spp Spider 8 15 12 34 56 210 132 1122

sedge Cyperus rotundus Nut Grass 21 33 0 0 420 1056 0 0

tree Bambusavulgaris Bamboo 6 4 0 0 30 12 0 0

tree Syzygium cumini Indian Blackberry/ Gulab Jamoon

0 0 0 3 0 0 0 6

tree Roupala montana Beef wood 0 0 0 43 0 0 0 1806

tree Acacia mangium White Teak 0 0 0 4 0 0 0 12

vine Merremia umbellata

Hog Vine 0 0 32 23 0 0 992 506

vine Momordica charantia

Cerasee Bush

3 6 7 0 6 30 42 0

N 1589 2206 2104 1392 300068

521604

516236

349300

N(N-1) 2523332

4864230

4424712

1936272

Species DiversityMean SD Overall

8.41 9.33 8.57 5.54

Amphibians and Aquatic

2.13 2.11 1.00 1.00

Grass and Ferns

2.35 2.90 1.47 1.42

Herbs 2.76 2.50 2.59 6.72

Insects and Arachnids

4.27 4.22 4.76 3.21


1.91 1.64 1.43 2.26

34

Site VisitsEntry number: 1

Date: 26/11/14

Location: Guayaguayare Beach

Map:

Map1 showing the location of coastal region A

Title: Environmental Survey of Coastal Region A

Objectives:




comparable to unpolluted coastal zones, and to test for other physicochemical parameters

including - Temperature, pH, Turbidity, Total Solids, Total Phosphates, Nitrates and

Alkalinity

Introduction:

Coastal Region A is located on the South Eastern part of Trinidad. The natural resources are oil and gas, while its human resources are agriculture and fishing.

35

Activities: 1. The class was divided into three groups with three students per group

2. The sites where the quadrats were to be placed for sampling were located

3. Each group then went to their respective site and carried out quadrat sampling

4. An estimate of the percentage of the types of plants, animals and pollution was recorded

for each quadrat sample taken

5. Samples of water from the beach and 2 nearby streams were taken and the LabQuest2 water quality testing package was used to test the pH, temperature and conductivity of each.

Observations:

- There was an oil well present (Figure 1.0)

Figure 1.0 showing the oil well seen at coastal region A

- The weather was sunny and clear

- There was a security booth present

- A moderate level of pollution was seen

36

- There were benches and bathroom facilities present (Figure 1.1)

Figure 1.1 showing the bathroom facilities present at coastal region A

- The water was light brown in colour

Discussions and Findings:

The presence of a security booth, benches and bathroom facilities indicated that this site is often used for various forms of human activity. This human activity would have therefore resulted in the moderate level of pollution seen. Furthermore, this pollution, along with the presence of the oil well would have therefore affected the colour of the water. Finally, the sunny weather would have affected the temperatures of the water from the beach and streams.

Follow Ups:

- All three groups gathered and pooled together their results

Conclusion:

From the observations, it can be concluded that this coastal region provides jobs for many persons of the energy, agriculture and fishing industry.

37

Entry number: 2

Date: 26/11/14

Location: Mayaro Beach

Map:

Map2 showing the location of coastal region B

Title: Environmental Survey of Coastal Region B

Objectives:






Alkalinity

Introduction:

Coastal Region B is located on the Eastern side of Trinidad. The natural resources are oil and gas, while its human resources are agriculture, fishing and commerce.

38

Activities:

1. The class was divided into three groups with three students per group






Observations:

- There were numerous fishing boats nearby (Figure 1.2)

Figure 1.2 showing some of the fishing boats seen at coastal region B

- Various lifeguards were seen at different locations of the beach

- Many beach houses were seen along the coastline

39

- A high level of pollution was seen throughout the beach (Figure 1.3)

Figure 1.3 showing the high level of pollution seen at coastal region B

- The weather was clear and sunny

- The water was brown in colour


The presence of various lifeguards and many beach houses indicated that this site is often used for recreational activities by humans. As such, the high level of pollution seen would thus be as a result of the recreational activities by humans. This pollution may have therefore affected the colour of the water. Furthermore, the presence of fishing boats indicated that this site is vital because many people obtain their source of income from it. Finally, the sunny weather would have affected the temperatures of the water from the beach and streams.

Follow Ups:


Conclusion:

From the observations, it can be concluded that this coastal region provides jobs for many persons of the energy, agriculture and fishing industry. Also, it also a favourite among most people for bathing and indulging in other recreational activities.

40

Entry number: 3

Date: 29/01/15

Location: Vessigny Beach

Map:

Map3 showing the location of coastal region C

Title: Environmental Survey of Coastal Region C

Objectives:






Alkalinity

Introduction:

Coastal Region C is located on the South Western Peninsula of Trinidad. The natural resources are oil and gas, while its human resources are agriculture, fishing and commerce.

41

Activities:







Observations:

- There was a Secondary School nearby

- There were numerous fishing boats nearby (Figure 1.4)

Figure 1.4 showing some of the fishing boats seen at coastal region C

- People were seen bathing in the beach

- A moderate amount of pollution was seen throughout the beach

- A cark park was present

- A security booth was present

- There were bathroom facilities present

- There was presence of a wastewater treatment plant


- The water was light brown in colour

42


The presence of a security booth, a car park and bathroom facilities indicated that this site is often used for various forms of human activity. People were also seen bathing in the water of the beach which thus indicated that this site is used for recreational activities by man. This, together with a Secondary School being present nearby, accounts for the pollution seen on the site. Also, the presence of fishing boats indicated that this site is vital because many people obtain their source of income from it. Furthermore, the presence of the water treatment plant, together with the pollution, would have therefore affected the colour of the water. Finally, the sunny weather would have affected the temperatures of the water from the beach and streams.

Follow Ups:


Conclusion:

From the observations, it can be concluded that this coastal region provides jobs for many persons of the energy, agriculture and fishing industry.

43

Entry number: 4

Date: 06/02/15

Location: Macqueripe Beach

Map:

Map4 showing the location of coastal region D

Title: Environmental Survey of Coastal Region D

Objectives:






Alkalinity

44

Introduction:

Coastal Region D is located on the North Western Peninsula of Trinidad. This region is used mainly as a tourist attraction with attractions such as a beach, a military museum and a national park.

Activities:







Observations:

- Lifeguards were present at the beach

- People were seen bathing in the beach

- There was a car park present

- There were dustbins for litter present

- There were benches and bathroom facilities present

- There was a zip line course present (Figure 1.5)

Figure 1.5 showing one of the zip line courses present at coastal region D

45

- There was little pollution present


- The water had a cloudy appearance


The presence of lifeguards, a car park, dustbins, benches and bathroom facilities indicated that this site is often used for various forms of human activity. A zip line course was present and people were also seen bathing in the water of the beach which thus indicated that this site is used for recreational activities by man. Little pollution was seen on the site and this may have been due to the visitors of the site making use of the provided dustbins for their litter. Finally, the sunny weather would have affected the temperatures of the water from the beach and streams.

Follow Ups:


Conclusion:

From the observations, it can be concluded that this coastal region provides jobs for many persons of the tourism industry. Also, it is a popular place of visit from many people because of the wide array of recreational activities.

46

Laboratory EntriesLab 1

Date: The lab was done on the same dates the site visits were carried out

Title: Biochemical Oxygen Demand

Aim: To determine the Biochemical Oxygen Demand (BOD5) of all four Coastal sites

Apparatus and Materials:

1. Vernier LabQuest2 interface2. Vernier Dissolved Oxygen Probe3. Dissolved Oxygen Filling Solution4. Biochemical Oxygen Demand Water Sample 5. Sodium Sulphite Calibration Solution 6. Pipette 7. 250mL beaker 8. Wash bottle with distilled water9. Sample water from each site10. 100% calibration bottle

Procedure:

Day 0

1. At each of the visited coastal zones, each of the three groups collected five water samples for the BOD test.

2. Each of the glass BOD sample bottles were then placed approximately 10cm below the water’s surface and kept there for 1 minute until all air bubbles were removed and the bottle was completely filled. The BOD bottle lid was secured tightly, while still submerged.

3. Each bottle was then wrapped in foil and labelled E1 to E5 and with the name of its corresponding coastal zone. The bottles were stored in ice and returned to the laboratory for testing.

4. At the laboratory, the bottles E1 to E5 were removed from the ice and the initial dissolved oxygen reading was measured using the LabQuest2 Dissolved Oxygen probe.

5. Sodium Sulphite solution was used to calibrate the LabQuest2 Probe. The probe was washed with distilled water and the readings of the samples were then taken.

6. The results were recorded in Table1 as the “initial dissolved oxygen level”.7. The BOD bottles were then placed in an incubator (dark closet) at around 27 °C for five

days.Day 5

8. The BOD bottles were removed from the incubator at approximately the same time of day they were placed into the incubator and the dissolve oxygen was measured following step 5.

47

Data Collection/Results:

Table 1 – Results of Group 1 showing the level of dissolved oxygen in samples E1 – E5 after 5 days for each site

Coastal Zone

Dissolved oxygen

E1 E2 E3 E4 E5 Average (BOD5)

(mg/L)A Initial (mg/L) 8.8 8.8 8.7 8.9 8.8

Final (mg/L) 5.4 5.7 5.3 5.6 6.4BOD (mg/L) 3.4 3.1 3.4 3.3 2.4 3.12

B Initial (mg/L) 9.3 9.2 9.9 9.1 9.1Final (mg/L) 4.5 4.4 4.3 5.7 4.5BOD5 (mg/L) 4.8 4.8 5.6 3.4 4.6 4.64

C Initial (mg/L) 11.1 11.1 11.3 11.1 11.2Final (mg/L) 6.9 6.8 6.8 6.6 6.8BOD5 (mg/L) 4.2 4.3 4.5 4.5 4.4 4.38

D Initial (mg/L) 7.3 7.7 7.5 7.5 7.7Final (mg/L) 4.8 4.7 4.4 4.6 4.7BOD5 (mg/L) 2.5 3.0 3.1 2.9 3.0 2.90

Data Analysis:

BODE1 = Final Dissolved Oxygen (mg/L) – Initial Dissolved Oxygen (mg/L)

BOD5 = BODE 1+BODE 2+BODE3+BODE4+BODE5

5 mg/L

The results for the values of BODE1 – BODE5 and BOD5 are shown in Table1 above.

Discussion:

This lab was done to determine the Biochemical Oxygen Demand of the water samples taken from each of the four coastal zones visited. In a “healthy” body of water, oxygen is replenished quicker than it’s used by aquatic organisms. However, in some bodies of water, aerobic bacteria decompose such a vast volume of organic material, that oxygen is depleted from the water faster than it can be replaced. The resulting decrease in dissolved oxygen is known as the Biochemical Oxygen Demand (BOD). Also, oxygen is vital to aquatic species as they use it to build energy through respiration. Dissolved oxygen is the form of oxygen accessible to aquatic organisms.

After testing, it was found that the average level of BOD in coastal zones “A” , “B” and “C” were calculated to be 3.12mg/L, 4.64mg/L and 4.38mg/L respectively. A level of BOD between 3mg/L – 5mg/L indicates that the water is moderately clean with some organic waste. As such, it can be deduced that the water in coastal zones “A”, “B” and “C” was moderately clean and contained some organic waste, and the aquatic organisms which live there would be able to live comfortably. In contrast, after testing, it was found that the average level of BOD in coastal zone “D” was calculated to be 2.90mg/L. A level of BOD between 1mg/L – 2mg/L indicates that the water is clean with little organic waste. As such, it can be deduced that the water in coastal zone

48

“D” was clean and contained little organic waste and the aquatic organisms which live there would be able to live comfortably.

Conclusion:

The BOD5 levels of the four coastal zones were investigated and determined. The BOD5 levels of the coastal zones “A”, “B”, “C” and “D” were 3.12mg/L, 4.64mg/L and 4.38mg/L respectively. All four coastal sites had acceptable BOD levels.

Limitations:

The resources and time were limited for this experiment and thus a simple method for the calculation of BOD5 was employed. As such, to obtain a precise measure of BOD5 it should be conducted over a longer period of time period so that the changes can be better observed, thus resulting in a clear cut representation of the various levels present in the water.

49

Lab 2


Title: Temperature, pH, Nitrates and Turbidity

Aim: To determine the Temperature, pH, Nitrates and Turbidity of all four coastal sites


1. Vernier LabQuest2 interface2. Vernier Temperature Probe3. Vernier Turbidity Sensor4. Vernier pH Sensor 5. Nitrate Ion-Selective Electrode 6. Wash bottle7. Sample water from each site8. Distilled water

Procedure:

1. Water samples were collected at each of the visited sites by placing the water bottles under water for 1 minute, until all the air bubbles were removed. The lid of the bottle was then tightened quickly under water. The bottle was then labelled “Bottle A” with the name of its corresponding coastal zone. The bottles were then taken back to the laboratory for testing.

2. The laboratory technician pre-standardised each probe before testing the samples.3. Each sample was tested in succession for Temperature, Turbidity, pH, and Nitrates. For

each test the relevant probe was connected to the LabQuest2 interface and placed into Sample bottle A and the reading recorded in Table 1.

4. Between each test the probes were washed and securely stored away.


Table 1 – Results of Group 1 showing the values obtained for pH, Turbidity, Nitrates and Temperature at the various sites

Coastal Zone pH Turbidity (NTU) Nitrates mg/L Temperature/°CA 6.31 18 3.9 24.44B 5.73 23 12.7 27.43C 6.84 17 2.4 24.50D 6.33 89 2.8 25.73

Discussion:

This lab was done to determine the Temperature, pH, Nitrates and Turbidity of the water samples taken from each of the four coastal zones visited. Temperature refers to the degree of heat and is a measure of the average heat or thermal energy of the particles in a substance. Many aquatic

50

organisms are cold blooded and have their own specific optimum temperature. Due to this, aquatic organisms can’t survive at temperatures below 00C and they are also intolerable to temperatures beyond 360C. It was determined that the temperatures of the samples of water for coastal zones “A”, “B”, “C” and “D” were 24.440C, 27.430C, 24.500C and 25.730C respectively. These temperatures were within the range required for the standard living of these organisms and as such the temperatures were not harmful to these organisms.

Also, aquatic organisms are extremely sensitive to the pH of their environment; if the pH of their environment is not between their optimum ranges, these species may become endangered as they won’t be able to survive and reproduce. The pH scale ranges from 0 – 14 with a pH of 7 being neutral, a pH of less than 7 being acidic and a pH of above 7 being basic. A pH of 6.5 to 8.2 is optimal for most organisms. It was found that the pH of the samples of water for the coastal zones “A”, “B”, “C” and “D” were 6.31, 5.73, 6.84 and 6.33 respectively. Thus, it can be inferred that the pH of the water of the four coastal sites visited was acceptable and allows the aquatic organisms to live there comfortably.

Furthermore, another parameter which was tested was turbidity. Turbidity refers to the measure of water’s lack of clarity. Water with high turbidity is cloudy, whereas water with low turbidity is clear. For aquatic life, turbidity levels should be less than 25 NTU. It was detected that the values of Turbidity of the samples of water for the coastal zones “A”, “B”, “C” and “D” were 18, 23, 17 and 89 NTU respectively. With respect to the coastal zones “A”, “B” and “C”, the turbidity was within the required range and as such the water was clear, allowing light to enter which thus allowed for the various life processes to take place. In contrast, the turbidity of coastal zone “D” was higher than acceptable. This therefore indicates that light isn’t being able to pass through the water which will thus cause a decrease in the dissolved oxygen levels and can suffocate the aquatic organisms which live there, thus resulting in death.

Finally, nitrates, which are soluble in water, and exits in water as No3-, are an essential source of

nitrogen required by plants and animals to synthesize amino acids and proteins. The acceptable nitrate in water level is less than 25 mg/L. Nitrate levels above this would result in an increase in plant growth and decay, promote bacterial decomposition and would also decrease the oxygen levels in water thus killing aquatic organisms which live there. It was found that the Nitrate level of the samples of water for the coastal zones “A”, “B”, “C” and “D” were 3.9mg/L, 12.7mg/L, 2.4mg/L and 2.8mg/L respectively. As such, the nitrate level of the water samples from the four coastal zones visited were within in the appropriate range thus allowing aquatic organisms to live there comfortably.

Conclusion:

The Temperature, pH, Nitrates and Turbidity of the water from the four visited coastal zones were investigated and determined. Coastal ecosystems “A”, “B”, “C” and “D” were within the required ranges for Temperature, which was 24.440C, 27.430C, 24.500C and 25.730C respectively and pH, which was 6.31, 5.73, 6.84 and 6.33 respectively. The turbidity level of the four coastal zones were 18, 23, 17 and 89 NTU respectively. Coastal zones “A”, “B” and “C” had an acceptable level of turbidity whereas coastal zone “D” had an unacceptable level. The level of

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Nitrates found in coastal zones “A”, “B”, “C” and “D” were 3.9mg/L, 12.7mg/L, 2.4mg/L and 2.8mg/L respectively. The nitrate level for all four coastal zones was within the appropriate range.

Limitations:

To obtain a specific evaluation of the water pollution these parameters should be collected over a longer period of time to allow the true levels and fluctuations to be seen.

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Lab 3


Title: Total Solids

Aim: To determine the total solids present in the water sample collected for all four Coastal sites


1. Analytical balance (0.001g) 2. Drying oven3. Tongs4. 100mL graduated cylinder 5. Four (4) 250mL beakers 6. Sample water from each site

Procedure:

1. Water samples were collected at each of the visited sites by placing the water bottles under water for 1 minute, until all the air bubbles were removed. The lid of the bottle was then tightened quickly under water. The bottle was then labelled “Bottle B” with the name of its corresponding coastal zone. The bottles were then taken back to the laboratory for testing.

2. A measuring cylinder was used to measure and pour 200 cm3 of sample water from each coastal site into each of the pre-dried and weighed 250mL beakers.

3. The beakers were placed in a drying oven at a 100 °C until the following day.4. The beakers were then removed and placed in a desiccator until they were cooled to room

temperature.5. Each beaker was weighed to determine the difference by mass.6. The results were tabulated in Table 1.


Table 1 – Results of Group 1 showing the amount Total Solids present in each water sample collected at the various sitesCoastal Zone Mass of

empty beaker (g)

Mass of beaker plus

solids (g)

Mass of solids (g)

Mass of solids (mg)

Total Volume (L)

Total Solids (mg/L)

A 97.850 97.865 0.015 15 0.2 75B 95.950 95.968 0.018 18 0.2 90C 103.550 103.567 0.017 17 0.2 85D 96.995 97.002 0.007 7 0.2 35

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Discussion:

This lab was done to determine the level of Total Solids present in the water samples taken from each of the four coastal zones visited. Total Solids is a measure of all the suspended, colloidal, and dissolved solids in a sample of water. It was detected that the values of Turbidity of the samples of water for the coastal zones “A”, “B”, “C” and “D” were 75, 90, 85 and 35 respectively. As such, it can be inferred that coastal zones “A”, “B” and “C” contained a high level of suspended, colloidal and dissolved solids. This may endanger the aquatic organisms which level there since a high level of Total Solids causes a decrease in the photosynthetic rate and also reduces water clarity. In contrast, coastal zone “D” contained a moderately low level of suspended, colloidal and dissolved solids. As such, the aquatic organisms which live there are able to live relatively comfortably.

Conclusion:

The levels Total Solids present in the four coastal zones were investigated and determined. The levels of total solids of the coastal zones “A”, “B”, “C” and “D” were 75, 90, 85 and 35 respectively. Coastal zones “A”, “B” and “C” contained high levels of total solids which were acceptable. Coastal zone “D” contained a low level of total solids which would endanger the aquatic organisms which live there.

Limitations:


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Lab 4


Title: Total Phosphates

Aim: To determine the total phosphates in the water sample collected for all four Coastal sites


1. LabQuest2 Interface2. Vernier Colourimeter 3. PhosVer3 Phosphate Powder Pillow 4. Sulfate Powder Pillows 5. Phosphate Standard (10.0 mg/L PO4)6. 2.63M H2SO47. 5.0M NaOH8. 0.1M HCl9. Four (4) 50mL Erlenmeyer flasks10. 10mL graduated cylinder11. 25mL graduated cylinder12. Sample water from each site13. Distilled Water14. Hot plate 15. One cuvette

Procedure:

1. Water samples were collected at each of the visited sites by placing the water bottles under water for 1 minute, until all the air bubbles were removed. The lid of the bottle was then tightened quickly under water. The bottle was then labelled “Bottle C” with the name of its corresponding coastal zone. The bottles were then taken back to the laboratory for testing.

2. A 25mL graduated cylinder was used to measure and place 25 mL of sample water from each coastal site into each flask.

3. Water samples from each facility were mixed as follows – a. One Sulphate powder pillow was added to each flask and swirled.b. A 10mL graduated cylinder was used to measure and add 2.0 mL of 2.63M H2SO4

to each flask swirled.c. The samples were boiled for 30 minutes while adding small amounts of distilled

water to keep the volume near, but not above 25mL. d. After 30 minutes, the flasks were removed from the hot plate and allowed to cool.e. A 10mL graduated cylinder was used to add 2.0mL of 5.0 M NaOH to each flask

and swirled to neutralise the acid. f. If a flask contained below 25 mL of liquid, the volume was made up to 25mL

using distilled water.

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g. One PhosVer3 Phosphate Powder Pillow was added to each sample and completely dissolved prior to reading on the colourimeter.

4. The phosphate standards and standard curve was already done for us by the University of Trinidad and Tobago and stored on the LabQuest2 interface for use in the determination of our sample readings. The data was tabulated in Table 1.

5. An empty cuvette was filled ¾ full with distilled water and the lid was sealed to prepare a blank.

6. The blank was then placed into the vernier colourimeter and the blank button was clicked on the interfaced.

7. The cuvette was washed after each reading and the samples for each site was then read on the colourimeter and tabulated in Table 2.


Table 1 – Results of Group 1 showing the Standards Absorbance ReadingsFlask

Number10.0mg/L PO4 Distilled

H2O/mLConcentration/mg/L

PO4

Absorbance

1 5 20 2 0.64342 10 15 4 1.3373 15 10 6 1.7444 20 5 8 2.379

Table 2 – Results of Group 1 showing the Absorbance Readings for the various sitesCoastal Zone Absorbance Total Phosphates

Concentration/mg/L PO4

Total Phosphorus Concentration/mg/L PO4

A 0.7560 2.35 0.768B 1.4895 4.63 1.513C 0.4279 1.33 0.435D 0.6820 2.12 0.693

Discussion:

This lab was done to determine the level of Total Phosphates present in the water samples taken from each of the four coastal zones visited. Minute amounts of phosphorus are required for all aquatic plants and algae as it is a vital nutrient to these species. An excess amount results in eutrophication, the condition whereby there’s an excessive richness in nutrients, which results in increased plant and algal growth. Eutrophication lowers the levels of dissolved oxygen in the water and makes the water uninhabitable by many aquatic organisms.

It was found that the values for the concentration of the Total Phosphates present in the samples of water for the coastal zones “A”, “B”, “C” and “D” were 2.35mg/L, 4.63mg/L, 1.33mg/L and 2.12mg/L respectively. These values were relatively low and as such it would not result in eutrophication, thus allowing aquatic organisms to live there easily.

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Data Analysis:

Calculation of Phosphorus –

Phosphorus (mg/L PO4-P) = phosphates(mg / L PO 4)

3.06

Conclusion:

The level Total Phosphates present in the four coastal zones were investigated and determined. The levels of total phosphates of the coastal zones “A”, “B”, “C” and “D” were 2.35mg/L, 4.63mg/L, 1.33mg/L and 2.12mg/L respectively. All four coastal zones contained acceptable levels of total phosphates.

Limitations:


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Lab 5


Title: Alkalinity

Aim: To determine the alkalinity of the water sample collected for all four Coastal sites


1. 0.00100M H2SO4solution (A1)2. Three 250 cm3 conical flasks3. 50mL burette4. 100mL graduated cylinder5. Sample water from each site (B1) 6. Wash bottle with distilled water 7. 25 cm3 pipette8. Methyl Orange9. Conical Flask

Procedure:

1. Water samples were collected at each of the visited sites by placing the water bottles under water for 1 minute, until all the air bubbles were removed. The lid of the bottle was then tightened quickly under water. The bottle was then labelled “Bottle D” with the name of its corresponding coastal zone. The bottles were then taken back to the laboratory for testing.

2. A1 (H2SO4) was then placed in a burette 3. 25 cm3 of B1 was then pipetted into a conical flask and two drops of methyl orange

indicator was added.4. This solution was titrated with A1 until it changed colour from yellow to orange/red.5. Readings were then recorded in Table 1. 6. The concentration of Alkalinity was determined assuming the following reaction –

H2SO4 + CaCO3 →H2O + CO2 + CaSO4


Table 1 – Results of Group 1 showing the Titration of B1 with A1 at the various sitesCoastal Zone A B C DFinal burette reading/cm3

6 17 26 29

Initial burette reading/cm3

0 6 17 26

Volume of A1 used/cm3

6.1 10.7 9.7 2.2

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Table 2 – Results of Group 1 showing the Alkalinity of the various sitesCoastal Zone Alkalinity/mg/L

A 33B 58C 53D 12

Discussion:

This lab was done to determine the level of Alkalinity present in the water samples taken from each of the four coastal zones visited. Alkalinity refers to the measure of how much acid water can neutralize. Alkalinity acts as a buffer as it protects water and its life forms from immediate changes in pH. It was found that the values for the level of Alkalinity present in the samples of water for the coastal zones “A”, “B”, “C” and “D” were 33mg/L, 58mg/L, 53mg/L and 12mg/L respectively. The alkalinity level in coastal zones “A”, “B” and “C” were relatively high and thus allowing for adequate protection of the water and aquatic organisms which live there against changes in pH. However, the alkalinity level for coastal zone “D” was low and as such the water and the aquatic organisms which live there will be highly affected by changes in pH

Data Analysis:

M1V1 = M2V2

M1 = 0.001 Molar H2SO4

V1 = Volume of H2SO4 titre into the conical flask

M2 = Concentration of CaCO3

V2 = 25 ml

Molar Concentration of CaCO3 (mol dm-3) to Mass Concentration of CaCO3 (g dm-3)

g/dm−3 ofCaC O3=M 2

136

¿mg /dm−3=M 2

136 ×1000

Conclusion:

The level Alkalinity present in the four coastal zones were investigated and determined. The Alkalinity levels of the coastal zones “A”, “B”, “C” and “D” were 33mg/L, 58mg/L, 53mg/L and 12mg/L respectively. Coastal zones “A”, “B” and “C” contained an acceptable level of alkalinity

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whereas coastal zone “D” contained an unacceptable level which may lead to the death of the aquatic organisms which live there.

Limitations:


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