Environmental Systems and Societies
Internal Assessment
Word count:1800 words
,Identifying the context:
Research question:
To what extent does (0.02,0.25.0.5,1) teaspoons of dishwashing soap in water affect
the level of DO (measured DO using DO probe) in a small, local, freshwater pond?
Environmental issue:
Decreasing aquatic productivity due to eutrophication taking place in the aquatic
ecosystem as soap (consisting of nitrates and phosphates) is dumped into the water
due to domestic activities
Water pollution is a big problem as wastewater from residential areas is dumped in
rivers.The wastewater consists of different nutrients which might lead to eutrophication
in the water. Eutrophication is the result of the discharge of nutrients in wastes from
homes and factories. Eutrophication occurs when there is excess nutrients in the water
that are discharged from households, causing algae to develop too quickly resulting in
algae bloom. Excessive algal growth also reduces the quantity of sunlight that enters
the water, resulting in a decrease in photosynthesis rates and a decrease in net primary
productivity.When the algae dies, anaerobic decomposition takes place which uses up
the oxygen in water. This results in a fall in the level of dissolved oxygen in water which
disrupts the food chain.Water's capacity for dissolved oxygen depends on factors such
as atmospheric pressure, temperature, and the amount of other compounds in the
water. Because of the increased atmospheric pressure at sea level due to disposal of
domestic waste, fresh water may absorb more oxygen per volume than water at higher
,elevations. As the temperature of the water drops, so does the amount of oxygen it can
hold.
Connecting the environmental issue to the research question:
My research objective is to see how dumping soap (nitrates and phosphates) into water
impacts the level of DO within, as well as leads to cultural eutrophication and how it
affects primary productivity in the aquatic ecosystem. Cultural eutrophication is the
process of speeding up human water pollution by dumping sewage, fertilizers and other
nutrient sources in water. This is an environmental concern because households dump
excessive amounts of contaminants into water from factories and households, causing a
drop in DO and disrupting aquatic ecology. As a result of the excessive growth of algae,
the primary production of the aquatic ecosystem will decline as light will not reach the
water and also lead to diseases of humans.
,Planning:
Hypothesis with justification:
I predicted a low level of DO with the more amount of soap added to the water. This is
because the soap content leads to an increase in the growth of algae in water. As a
result, the photosynthesis level falls due to lack of sunlight and oxygen available in the
water. Therefore, I hypothesize that the primary productivity of the aquatic ecosystem
will fall. It will lead to the death of aquatic organisms due to the lack of oxygen. As there
is a lack of oxygen there will be a high biological oxygen demand in the aquatic
ecosystem. Biological oxygen demand is the oxygen required to decompose material in
an anaerobic environment.
Identifying the variables:
Independent- Soap (The amount of soap added to the water sample)
Dependent- Dissolved oxygen ( measured using a DO probe)
Controlled-I kept the DO meter for 10 secs in the water and shook it a little bit before
taking it out of the water, collected all the water from the same pond, kept all the
beakers in the sunlight and kept the beakers in room temperature for 7 days.
Methodology:
1) I chose a pond which was accessible to me. The pond has a healthy aquatic
system and it also had some algae, this was intentional so that I could see if the
, algae grows with the more amount of soap I put in the water sample and the
effects of algae on the level of DO.
2) I measured the DO in different points of the pond, I chose that by random
sampling as it gave me an unbiased representation of the entire population.. I
took 10 readings and did the average to get a more precise value for the level of
DO of the water sample.
3) Then I divided the water sample in 5 groups, each group consisting of 5, 80ml
beakers. In group 1, there was no soap added to the water sample. In group 2, I
added 0.02 teaspoon of soap to the water. In group 3, I added ¼ teaspoon of
soap to the water. In group 4, I added ½ teaspoons of soap to the water sample.
In group 5, I added 1 teaspoon of soap.
4) The amount of soap added to the water was based on the information of how
much soap a household uses . An average household uses 1 teaspoons of soap
per 5 liters of water
5) I covered the small beakers with a cling film so that the water does not get
contaminated by anything before taking the second DO reading and left it in a
place with light source for one week in room temperature
6) I measured the DO readings after a week to see the change in DO from Day 1 to
Day 7
7) I took the average reading of the level of DO in water, and found the correlation
of the amount of soap added to the water and the level of DO.
8) Justifying the sampling strategy:
Internal Assessment
Word count:1800 words
,Identifying the context:
Research question:
To what extent does (0.02,0.25.0.5,1) teaspoons of dishwashing soap in water affect
the level of DO (measured DO using DO probe) in a small, local, freshwater pond?
Environmental issue:
Decreasing aquatic productivity due to eutrophication taking place in the aquatic
ecosystem as soap (consisting of nitrates and phosphates) is dumped into the water
due to domestic activities
Water pollution is a big problem as wastewater from residential areas is dumped in
rivers.The wastewater consists of different nutrients which might lead to eutrophication
in the water. Eutrophication is the result of the discharge of nutrients in wastes from
homes and factories. Eutrophication occurs when there is excess nutrients in the water
that are discharged from households, causing algae to develop too quickly resulting in
algae bloom. Excessive algal growth also reduces the quantity of sunlight that enters
the water, resulting in a decrease in photosynthesis rates and a decrease in net primary
productivity.When the algae dies, anaerobic decomposition takes place which uses up
the oxygen in water. This results in a fall in the level of dissolved oxygen in water which
disrupts the food chain.Water's capacity for dissolved oxygen depends on factors such
as atmospheric pressure, temperature, and the amount of other compounds in the
water. Because of the increased atmospheric pressure at sea level due to disposal of
domestic waste, fresh water may absorb more oxygen per volume than water at higher
,elevations. As the temperature of the water drops, so does the amount of oxygen it can
hold.
Connecting the environmental issue to the research question:
My research objective is to see how dumping soap (nitrates and phosphates) into water
impacts the level of DO within, as well as leads to cultural eutrophication and how it
affects primary productivity in the aquatic ecosystem. Cultural eutrophication is the
process of speeding up human water pollution by dumping sewage, fertilizers and other
nutrient sources in water. This is an environmental concern because households dump
excessive amounts of contaminants into water from factories and households, causing a
drop in DO and disrupting aquatic ecology. As a result of the excessive growth of algae,
the primary production of the aquatic ecosystem will decline as light will not reach the
water and also lead to diseases of humans.
,Planning:
Hypothesis with justification:
I predicted a low level of DO with the more amount of soap added to the water. This is
because the soap content leads to an increase in the growth of algae in water. As a
result, the photosynthesis level falls due to lack of sunlight and oxygen available in the
water. Therefore, I hypothesize that the primary productivity of the aquatic ecosystem
will fall. It will lead to the death of aquatic organisms due to the lack of oxygen. As there
is a lack of oxygen there will be a high biological oxygen demand in the aquatic
ecosystem. Biological oxygen demand is the oxygen required to decompose material in
an anaerobic environment.
Identifying the variables:
Independent- Soap (The amount of soap added to the water sample)
Dependent- Dissolved oxygen ( measured using a DO probe)
Controlled-I kept the DO meter for 10 secs in the water and shook it a little bit before
taking it out of the water, collected all the water from the same pond, kept all the
beakers in the sunlight and kept the beakers in room temperature for 7 days.
Methodology:
1) I chose a pond which was accessible to me. The pond has a healthy aquatic
system and it also had some algae, this was intentional so that I could see if the
, algae grows with the more amount of soap I put in the water sample and the
effects of algae on the level of DO.
2) I measured the DO in different points of the pond, I chose that by random
sampling as it gave me an unbiased representation of the entire population.. I
took 10 readings and did the average to get a more precise value for the level of
DO of the water sample.
3) Then I divided the water sample in 5 groups, each group consisting of 5, 80ml
beakers. In group 1, there was no soap added to the water sample. In group 2, I
added 0.02 teaspoon of soap to the water. In group 3, I added ¼ teaspoon of
soap to the water. In group 4, I added ½ teaspoons of soap to the water sample.
In group 5, I added 1 teaspoon of soap.
4) The amount of soap added to the water was based on the information of how
much soap a household uses . An average household uses 1 teaspoons of soap
per 5 liters of water
5) I covered the small beakers with a cling film so that the water does not get
contaminated by anything before taking the second DO reading and left it in a
place with light source for one week in room temperature
6) I measured the DO readings after a week to see the change in DO from Day 1 to
Day 7
7) I took the average reading of the level of DO in water, and found the correlation
of the amount of soap added to the water and the level of DO.
8) Justifying the sampling strategy:
