Sample+Analysis

Sample ANALYSIS #1-can you find errors? What is good and not so good about it?

During the experiment, it was noticed that there were many positive and negative changes in both the experimental and control columns. The overall health of both columns was quite good until the day the insecticide was added to the variable column. Soon after the insecticide was added, there were immediate negative effects as the fish dying in the pond section and all the organisms in the forest section disappeared within two days. The fish did not die in the control columns, however the draining system also did not work as well as anticipated, which may have contributed to the accelerated rate of death of all organisms in the flooded forest section. Plant growth was stunted in the variable column as seen by the fact that the ferns started to droop and fall over one day after the variable was added. However, in the control column, the ferns actually ended growing a total of 1.30 cm. Soil pH in both sections of the control ecocolumn tended to remain close to a neutral reading (7.0) while those in the variable column were quite acidic with final readings of 5.8 and 5.9. This decrease in pH could have been one of the reasons why the plants and animals did not fare well in the variable column. The grass in both columns saw increased growth (0.4 cm in control and 0.5 cm in variable), however, the grass in the variable ecocolumn did slowly turn a yellow and brown color. This may have been due to the insecticide although we did notice some discoloration in the control column’s grass as well. The plants in the control ecocolumn all grew except for the pine saplings, which fell over. This was most likely due to the fact that the sapling was not planted very well and was not able to take root. Although we thought the worms died in both ecocolumns, when we took the control ecocolumn apart, we noticed that a baby worm was in the soil, which had not been there in the beginning. We also found both of our worms in the control ecocolumn. They were plump and healthy looking. In the pond section the microscopic organisms seemed to be at about the same population levels in both columns except the diatoms of the experimental, which have completely disappeared. Again, it is possible that the acidic levels were harmful to these particular organisms. The rrots of the pond plants in the experimental seemed to be thinner and less extensive than those in the control, another possible effect of the pH differences. In this experiment there were some sources of error involved. The biggest source of error was that the drainage system did not work as well as planned. The insecticide and “rain” flooded the forest section in the variable column for the entire duration of the experiment. An improvement would be to make more holes in the cap as well as in the bottom of the bottle to increase the percolation of “rain.” Different choices would be made for the saplings as they did not root well--perhaps more careful digging to be sure the whole root was obtained.

Sample ANALYSIS #2- Errors? Is this better or worse than the 1st? Why?

The experiment pretty much supported our hypothesis that insecticide would kill everything when it was added. On the first day after the variable was added, the fern height went from 8.3 cm to 8.2 cm. The next day, fern height was 8.1 cm and then it was 7.8 cm. It finally ended up at 7.4 cm. The pine sapling also got flooded after the insecticide was added and it ended up falling over. It started at 7.35 cm and then went to 7.4 cm, then to 4.5 cm and finally ended up at 4.0 cm. The animals also all died because they were not seen after the insecticide was added, although, a baby worm was found in the forest section. The PH of the soil in the variable ecocolumn was very acidic probably because of the insecticide. It went from 6.75 to 7 and then to 5.5 and finally ended up at 5.9 which was wicked low. The water PH went the other way and became basic. It started at 7 for two days and then went to 8.25, 8 and 8.5 and finally ended up at 8. The fish died soon after the spike in PH. The control column did not have many changes in The control column did pretty well considering the fact that everything survived and grew. The fish lived for the entire experiment and we found two humongous worms on take apart day in the forest section. The plants grew too. The ants disappeared but that was probably due to human error. The water plants did pretty well too since they didn’t die. There were few problems with the ecocolumn set-up. The only problem was the flooding that occurred after it ‘rained.” In the future that could be fixed pretty easily. The only errors were human ones. Nobody’s perfect, even scientists, right? When water was added we probably should have stopped because we flooded the top section. Maybe poking some holes somewhere would help too. Other than that, there were few problems with the set-up of the ecocolumns. Our group got along well but some members could have been better at recording. We were stressed a lot and should have asked for help. A principle that was shown was that life goes on. A second principle was the balance of chemicals in the environment. A third principle was reproduction.