The habitats of aquatic organisms

Aquatic species’ environments have a significant effect on their feeding times, longevity, and reproductive processes. The optimum habitat for all metabolic processes within these organisms’ systems is provided by optimal conditions. Extreme environmental trends have a significant impact on Artemia franciscana (Gajardo & Beardmore 2012). Temperature, pH, and other environmental factors can have an effect on the naupliar stage of this organism. It is well recognized that A. franciscana can tolerate intense temperature, light strength, and pH conditions. However, it has a high positive response to room temperature, and optimum light intensity and pH. In regards to acidity, Artemia franciscana has high survivability in conditions ranging from neutral to a pH. of 8. This pH. is available in saline conditions which are the most favorable condition which A. franciscana inhabits (Gajardo & Beardmore 2012). A. franciscana mainly inhabits shallow ends of the water which provides a good access to the light of high intensity. It is hypothesized that Artemia franciscana responds erratically to variations in light intensity.

The main objective of this experiment is to test the response of the first naupliar stage of A. franciscana to variations in light intensity pH. varying gradients of temperature and the varying pH. concentrations. The results obtained in this experiment will provide a basis to infer A. franciscana’s preferences to light intensity, temperature, and PH. The experiment will also aim at answering the question on whether A franciscana selects the most favorable habitats condition in its nauplii stage and which are the most favorable conditions for maximum hatching in Artemia franciscana.

Methods

Each bench was given a culture of A .franciscana that had been hatched overnight, plastic tubing attached to a meter rule, beakers and serum caps.

1. All treatments

The A. franciscana culture solution was well-mixed and added into each tube filling it. A serum cap was used to seal the end of the tube. The tube was rolled over 10 times end to end to allow even distribution of the solution.

The filled tubes were placed horizontally side to side aligned with the zero mark of the ruler.

Clamps were placed on each tube at the 25, 50 and 75 marks of the tubes. Specific treatments ensued as follows.

2. Light Treatment.

On the 25 mark, a vertical wood was placed on the side by side tubes.

A bright lamp was placed 1 meter above the tubes. The tubes had the dark section, translucent section, room light section and bright light section.

3. pH. Treatment

With a syringe, 0.1 ml 0.5% hydrochloric acid was injected into the serum caps ends at sec. 4. Additionally, 1 ml of 0.5% potassium hydroxide was injected into the section 1 of the serum caps ends. The pH. readings were made.

4. Temperature Treatment

A plastic bag was filled with ice and sealed. The tubes were covered with a paper towel and the plastic bag was then placed on section 1 of the tubes.

A heat lamp was placed 30 cm above the tubes on section 4 of the tubes.

5. continuation of all treatments

All the tubes were left to stand for 30 minutes undisturbed.

They were carefully clamped and the content of each section emptied into different beakers, for each section. The temperature and ph. for the respective tests were measured and recorded. For each section, the number of the Artemia franciscana were counted and recorded.

Results and Observations

Treatment

Bright

Room

Dim

Dark

Row totals

Light: Tube 1

56

51

76

87

270

Tube 2

34

64

74

73

240

Section Totals

90

115

150

160

510

Table 1. Shows the results of the light treatment. It is evident that there was a high number of the A. franciscana in dark environment. In tube 1 and highest in a dim environment in tube 2. Least number was observed in the tube in bright light intensity in tube 2.

Treatment

Sec. 1

PH.

Sec. 2

PH

Sec. 3

PH

Sec. 4

PH.

Row Totals

Ph. Tube 1

5

2.9

36

6.38

57

7.88

61

10.45

159

Tube 2

4

2.56

55

6.30

54

7,34

64

10.68

157

Section Totals

9

91

111

105

316

Table 2. Shows the pH treatment. The highest number was observed in the pH of above 7 while least number recorded for low PH. of 2 for both tubes.

Treatment

Sec. 1

temp

Sec. 2

Temp

Sec. 3

Temp

Sec. 4

Temp

Row totals

Temperature:Tube 1

34

15

71

23

80

26

74

31

270

Tube 2

53

19

66

21

60

23

85

26

240

section totals

87

17

137

22

140

24.5

159

28.5

515

Table 3. Shows the results for temperature treatment. The highest number was recorded for the temperature of 26 degrees Celsius while least for the temperature of 15 degrees Celsius for both tubes.

Discussion

According to the results obtained, it is evident that light intensity has an impact on hatching in Artemia franciscana. The total number of A. franciscana obtained in both tubes id s higher in the dark section of both tunes followed by the dim section. The low number is recorded on the bright section of the tubes (Browne & Wanigasekera 2000). This is because; in low light intensity there is high metabolism of carbohydrates. This an increase the release of trehalase enzyme which increases the absorption of glycogen and glycerol components in the aquatic environment by the cysts. An increase in absorption of these components decreases the compactness of the shell of the cysts(Browne & Wanigasekera 2000). Therefore there is more hatching of the cysts. On the contrary high light intensity in bright section decreases the production of trehalose which in turn lowers the absorption rate of she’ll-weakening components hence low hatching which explains the reason for a low number of Artemia franciscana in bright sections (Browne & Wanigasekera 2000).

Temperature 26 degrees Celsius is the most favorable for high hatching of the cysts. It favors all metabolic activities behind the weakening of the shell for hatching. High pH of approximately 8 is the most favorable for hatching in the naupliar stages of A Franciscana.

Conclusion

All environmental factors are important in hatching in A. franciscana. Extreme conditions have a counter effect on the metabolism activities involved in hatching. Inconsistency in the number may be sourced from possible experimental errors and variations in such factors as light intensity and wavelengths (Browne & Wanigasekera 2000).

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