This experiment is to investigate the tolerance level of grey water in tomato plants and what effect the gray water will have on the environment?
The hypothesis is that plants are able to tolerate small amount of detergent, but after the detergent solution reach it’s threshold level, it can affect the plant’s growth, ultimately resulting in the plants death.
Water is essential to the all life on earth, including plants. But with the growth of population, humans are facing more and more water problems: including water pollution and water shortage. It has become the biggest problem in the world to date. Most of the water pollution is caused by the heavy industries,pollution, and grey water discharged by households on a daily basis.
Byrne, J, 2005, Fact Sheet: Grey Water, Accessed on 12th March
Detergent are defined as "a cleansing substance that acts similarly to soap but is made from chemical compounds rather than fats and lye" (The American Heritage Dictionary of the English Language). Modern detergents contain a chemical called a surfactant which can cause water and soil pollution and is quite harmful to plants. An average Australian house can produce about 400 litres of grey water a day. This water may not be used again. But with rising costs and people’s awareness of saving water, more and more people start to use their water resources more wisely. The Australian Government encourages citizens to use grey water for the garden, for example waste water from the bathroom, hand basin, shower, and laundry can be used to water the household plants. However, the statistic ( Table 1 and Table 2) shows that the detergent water may affect the plant’s growth. The detergent would remove the waxy coating on the leaves of the plants, making it difficult for gas exchange to occur. Also the detergent solution would remove the membrane e the leaf cell and dry out. The plants would die eventually.
The experiment requires 12 plants, several spray bottles and beaker, detergent, and measuring cups.
The 12 individual tomato plants were separated into three groups and label carefully. The first group would be used to examine how the detergent solution affects the leaves of the plants. This group would be given different amounts of detergent solution spray every day. The four plants in this group are individually labeled as A1, A2, A3 and A4. The plant leaves would be sprayed regularly by 10%, 15%, 20% and 25% detergent solution mixed with water respectively.
The Second group would be used to examine how the detergent affects the plants roots by watering the plant with different amounts of detergent every day. The four plants in this group were labeled in the similar way as the first group and we watered with different levels of detergent concentration 10%, 15%,...