4.1 Analysis of results
From the graph plotted, it shows that the water hyacinth is not able to reduce the salt concentration.
4.2 Key findings
The Key findings concluded that cups 2,3,4,5,6 were found dead on day 4. Cup 1 was the only one alive possibly because only 1g of salt was put inside the water. This means that the concentration of salt is to high, the water hyacinth would not be able to cope with the salt.
4.3 Explanation of key findings
Cups 2,3,4,5,6 were dead due to the possibility that the salinity in the water(ppt) was too high, resulting it to die as a result. This may possibly make water hyacinth a good bioindicator as it dies easily when there are pollutants in the water. The readings may have fluctuated as when the water hyacinth die it may discharge the pollutants causing the readings to fluctuate.
4.4 Evaluation of Hypothesis
The hypothesis was that the water hyacinth should absorb most of the salt(NaCl) resulting in the water hyacinth to be highly effective in absorbing salt. Making it a good environmental cleaning agent. However our concentration used could be too high that the water hyacinth could not cope
4.5 Areas for improvement
a)We did not account for the evaporation, next time we should place a cling wrap over the top of the cup to minimise evaporation.
b)We should have a control setup of a water hyacinth without any salt and see if there is a change in the ppt.
c) we should have carried out the experiment in the open so that there is sufficient sunlight for the plants to grow