Table 22 Amended pH Changes Over Time 10 Daphnia Magna Temperature Resilience I

Table 22 amended ph changes over time 10 daphnia

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Table 2.2 - Amended pH Changes Over Time 10
Daphnia Magna Temperature Resilience: I. Pritchard 2017 The pH of all tanks shows a slight increase of at least 0.2 pH over the span of 12 days. The room temperature tap water tank started at 7.1 and declined by 0.1 initially before reaching a final pH of 7.4. The tanks A2, A5, and A6 all showed the same initial pH. Tank A2 is the only of these three that did not have the same final pH, it was 0.1 higher than the other two. The room temperature spring water tank had the highest initial pH of 7.4 and the highest final pH of 7.6. Table 2.3 - Amended Temperature Change Over Time 11
Daphnia Magna Temperature Resilience: I. Pritchard 2017 There is overlap of data between A4 & A6 and A3 &A5 after the initial 3 days. The control tanks showed a small rise in temperature after the first 3 days but remained constant throughout. The tanks with added heat increased in temperature by about 16 degrees Celsius after the adjustment period of 3 days. For both amended and control tanks the temperature was relatively consistent through the 12 days. Discussion The results of this experiment suggest that D.Magna are not a adaptable to climate variability as previous researchers like Fischer, J et al. (2011) have thought. The continuous decline in population of the heated tanks of both temperature strata supports that D.Magna are not adaptable. The continuous increase of pH levels in all of the tanks suggest bacteria growth or an overgrowth of organic matter. An increase of organic matter could be a result of the D.Magna 12
Daphnia Magna Temperature Resilience: I. Pritchard 2017 deaths and decomposition. There would need to be a rapid rate of decomposition for the rate of pH increase over the three week data period. My thoughts are that this could be due to a bacterial infestation due to an influx of D.Magna supplement food. The bacteria would break down dead D.Magna quicker and cause pH to rise. The temperature monitoring showed steady consistence which allows us to be confident in the control of our tank environments. If there were to be a fluctuation in temperature we would need to consider this into the death rates of the D.Magna . The external factor to be considered as the possible marker for why our populations declined when past studies populations increased under similar conditions is solar ultravioet radiation (UVR). Past studies showed that “ D. middendorffiana grew best when incubated in warmer and lower UVR conditions….” ( Fischer, et al., 2011). Due to the natural light and artificial LED lighting from the lab room the experiment was conducted in there could have been a higher UVR condition than desirable. UVR can damage aquatic biota the high energy, short wavelengths. To reduce UVR harm “accumulation of red carotenoids or synthesis of black melanin are efficient and safe where hunting fish are absent.” ( Rautio, M., & Tartarotti, B., 2010 ). In aquatic systems where hunting fish are present UVR absorbing cover plants such as Nitella and Bladderwort can be used. Lowering the amount of UVR could be a buffer for

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