Tuesday, September 10, 2013


An investigation on water plants serving as a bio-indicator in determining the quality of water.

Wednesday, July 10, 2013

Literature Review : Growth of Duckweeds

The plant we are going to use in the experiment will be duckweed, therefore learning about its growth is essential in order to carry out the experiment properly and accurately.

The recommended conditions to grow duckweed in would be with moderate conditions of light and temperature. It must also be contained in a liquid with necessary nutrients. However, duckweed is very adaptable and therefore can grow easily in most conditions

In order to start growing duckweed, it needs to be placed in a container with water in it. Preferably a open container since it will allow the heat to escape, cooling the container. The temperature and light level of the set-up must also be monitored and kept at moderate levels since the experiment is about water quality, therefore other variables must be kept constant. It is important to keep the set up clean. The water will contain a variety of other organisms.  These will include bacteria, fungi, algae, protozoa, and even small multicellular animals and insect larvae. 

All other variables other than the water quality must be kept constant in order for the experiment to be accurate. The conditions the set-up is in must also be suitable for plant growth such that only the water quality might kill the plant.

Landolt, E. and Kandeler, R. (1987) The family of Lemnaceae - a monographic study Retrieved July 10 2013 http://www.mobot.org/jwcross/duckweed/growing-duckweed.htm

Literature Review : What is harmful to duckweed

Duckweed are free floating plants whose population can attain nuisance levels in Ohio ponds. Their explosive reproductive capacity can quickly cause a pond to be completely covered in the green plants in just a few weeks. 

There are many ways how to figure out what is affecting the duckweeds, causing it to be harmful towards it. When the temperature is cool, massive duckweeds will die off. Removing the weed naturally, administering weed control chemicals and also installing a bubble aerator will eliminate duckweed.

Duckweed and Watermeal: Prevention and Control, Ohio State University Extension Fact Sheet Retrieved by July 9, 2013 from http://ohioline.osu.edu/a-fact/0014.html

Monday, July 8, 2013

Literature Review : Measuring Plant Growth

Plant growth is vital in our project as it determines the results as it shows the effect of water quality on the plants. 

There are different ways to measure plant growth. One of them is to count the number of plants multiplied but there are other ways like weighing the plants, finding the root mass, the root shoot ratio and Leaf Surface Area. 

To weigh the plants one must remove it from its growing medium (in this cause water) and remove any free surface moisture before weighing it. Root mass is recommended as a final measurement as the plant must be removed from its growing medium in order to capture accurate data.The root:shoot ratio is one measure to help you assess the overall health of plants. For example, an increase in root:shoot ratio could be an indication of a healthier plant, provided the increase came from greater root size and not from a decrease in shoot weight. The Leaf Surface Area method is to trace the plant's leaf on a pice of graph paper and cut it out. This helps to determine if the plant is growing and its growing rate.

There are many methods of measuring plat growth. More than one can be used to ensure accuraccy of out results.

Missouri Botanical Garden. (2003, May 3). Measuring Duckweed Growth Retrieved July 7, 2013 from http://www.mobot.org/jwcross/duckweed/duckweed-measuring-growth.htm

Saturday, July 6, 2013

Literature Review :Water Quality


Water quality is defined in terms of the chemical, physical and biological content of water. The water quality of rivers and lakes changes with the seasons and geographic areas, even when there is no pollution present. There is no single measure that constitutes good water quality. For instance, water suitable for drinking can be used for irrigation, but water used for irrigation may not meet drinking water guidelines. The quality of water appropriate for recreational purposes differs from that used for industrial processes.

Good water quality
Good quality drinking water is free from disease-causing organisms, harmful chemical substances, and radioactive matter. It tastes good, is aesthetically appealing, and free from objectionable color or odor.
It should be noted that there is a difference between "pure water" and "safe drinking water". Pure water, often defined as water containing no minerals or chemicals, does not exist naturally in the environment. Under ideal conditions, water may be distilled to produce "pure" water. Safe drinking water, on the other hand, may retain naturally occurring minerals and chemicals such as calcium, potassium, sodium or fluoride which are actually beneficial to human health and may also improve the taste of the water. Where the minerals or chemicals occur naturally in concentrations that may be harmful or displeasing, then certain water treatment processes are used to reduce or remove the substances. In fact, some chemicals are actually added to produce good drinking water; the best examples of chemical addition are chlorine used as a disinfectant to destroy microbial contaminants, or fluoride used to reduce dental cavities.

Bad water quality

There are many factors which causes bad water quality, those which may affect the growth of plants are:
Sewage Pollution - Harmful chemicals may be release together with the sewage.
Oil and other chemicals - Toxic to aquatic life and plants.
Detergents - Toxic to aquatic life, which decrease the amount of nutrients in the water for the plants.
Weeds - Takes in nutrient in the water > lesser nutrient in water > lesser nutrient for other water plants.
Litter and rubbish - Encourages weed growth.

Upper Parramatta River Catchment Trust (2001) Causes of poor water quality


CSREES Florida water quality programme(November  20 2007) Water quality


Wednesday, July 3, 2013


Title: An investigation on using Human urine as a Fertilizer
Hypothesis : Human urine can help plants grow better and act as a 

Title: An investigation on whether people can accurately determine if a 
        smile is genuine or fake.
Hypothesis : People can determine if a smile is genuine.

Title: An investigation on water plants determining the water quality.
Hypothesis : If the quality of water is poor, the number of duckweeds in it 
                   will decrease.

Project Guide

Project 1: An investigation on using Human urine as a fertilizer

Project 2 : An investigation on whether people can accurately determine if a smile is genuine or fake.

3. An investigation on water plants determining the water quality

Tuesday, July 2, 2013

Monday, July 1, 2013

What is Scientific Method?

The scientific method is a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry must be based on empirical and measurable evidence subject to specific principles of reasoning.