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inland Australia with high levels of suspended sediments and low levels of dissolved oxygen. Other small fish and debris were also introduced to the ring tank during water harvesting activities. Unlike riverine water, the groundwater that was pumped into the ring tank was of high quality and contained no particulate or suspended matter. The volumes of bore water added to the ring tank did not appear large enough to influence ring tank water quality. Of the water harvested from the Condamine River, virtually all passed through the aquaculture ring tank before being transferred to other on-farm storages. Water can be drained from the aquaculture ring tank via a gate valve into an adjacent head ditch that can be used to irrigate adjacent fields or the water can be moved to the lagoon dam. This drainpipe draws directly from underneath the aquaculture infrastructure (cages/raceways). The ring tank can also overflow into the adjacent cell which again is set up to move water either to the lagoon dam or the irrigation head ditch. 3.3.2 Water Quality 3.3.2.1 Dissolved Oxygen Flood harvesting events were the most influential factor governing the variability in dissolved oxygen (DO) levels. The ring tank morning DO levels for surface water (SF) in January 2001 averaged 9.21 ± 0.61mg/L (Table 3.3.2). On the 04/02/01 a major riverine pumping event commenced. At the end of this 10 day pumping event the morning SF DO levels had fallen to just 3.5 mg/L. They remained below 5 mg/L until the 23/02/01 after which they began to slowly rise reaching an average of 6.50 ± 1.09 mg/L in May. In late 2001 a series of riverine and bore pumping events that occurred between the 15/11/01 and the 10/12/01 were again associated with a decrease in ring tank DO levels. The average morning SF DO level was 7.14 ± 0.48 mg/L for the month prior to the first 4 day riverine pumping event. Two subsequent riverine pumping events on the 20th and 28th of November lasted two and six days respectively. These riverine pumping events also coincided with bore water pumping activity on the 11th and the 22nd of the same month. The morning SF DO level for the week following this series of pumping events averaged 4.53 ± 0.54mg/L. For an extended period between the 10/12/01 and the 26/02/03 there were no riverine pumping events. In early December 2003 a pumping event lasting 13 days resulted in an immediate drop in SF DO levels. The morning DO level in SF waters In November 2003 averaged 5.23 ± 0.95 mg/L compared to the December average of 3.83 ± 1.34 mg/L. The lowest morning DO level observed during the pump event in December was 1.92 mg/L on the 16/12/03. Low DO levels were maintained in January and February 2004 with another two pumping events. The January, February and March 2004 morning SF DO levels averaged 3.22 ± 0.33, 3.02 ± 0.38 and 4.08 ± 0.79 mg/L respectively. Afternoon DO levels for these months were similar and averaged 3.41 ± 0.42, 3.38 ± 0.42 and 4.23 ± 0.58 mg/L respectively. In contrast to riverine pumping events, isolated bore water pumping events were not associated with any decrease in ring tank DO. A 31 day bore pumping event that commenced on the 27/10/00 was not associated with any fall in DO levels. The morning surface DO levels prior to this pumping activity averaged 9.54 ± 0.77 mg/L. The DO concentration during this pumping event averaged 9.13 ± 0.69 mg/L and was 8.2 mg/L the day after pumping ceased. Similarly a 12 day bore pumping event that commenced on the 12/09/00, also had no detrimental impact on ring tank DO levels. The morning surface DO level in the ring tank on the 24/09/00, the day after pumping ceased, was 8.39 ± 0.17 mg/L. This compares favourably with the DO levels observed in surface waters in the week prior to this pumping event which averaged 9.07 ± 0.46 mg/L. Similar observations were made for DO levels following bore pumping events on the 12/09/01 and the 15/11/2001. 10
Table 3.3.2 Average monthly morning surface (SF) and floor (FL) dissolved oxygen levels (mg/L) in the aquaculture ring tank from November 2000 to March 2004 (mean ± standard deviation) Month 2000 2001 2002 2003 2004 SF FL SF FL SF FL SF FL SF FL January 9.21 8.56 6.34 5.45 6.50 4.20 3.22 3.00 ±0.61 ±0.84 ±0.65 ±0.73 ±1.33 ±1.77 ±0.33 ±0.35 February 4.58 3.28 6.67 4.75 6.27 4.58 3.02 2.62 ±1.17 ±0.67 ±0.55 ±0.87 ±1.14 ±1.13 ±0.38 ±0.48 March 4.73 3.68 7.09 5.16 5.85 4.83 4.08 3.85 ±0.66 ±1.45 ±0.58 ±1.47 ±0.99 ±0.97 ±0.79 ±0.78 April 5.77 5.12 6.17 5.44 6.39 4.62 ±0.32 ±0.59 ±0.39 ±0.50 ±1.29 ±0.87 May 9.18 6.50 6.08 7.00 6.51 6.66 5.49 ±0.41 ±1.09 ±1.13 ±0.46 ±0.61 ±0.71 ±1.13 June 10.13 8.29 8.01 7.74 6.84 7.49 6.43 ±1.06 ±0.43 ±0.44 ±0.73 ±0.85 ±0.84 ±1.35 July 10.35 9.95 9.63 9.44 8.54 7.43 8.05 7.45 ±0.22 ±0.27 ±1.02 ±1.05 ±0.54 ±0.55 ±0.77 ±0.65 August 11.35 10.55 9.22 8.80 8.04 6.87 7.29 6.62 ±0.21 ±0.35 ±0.70 ±0.60 ±0.84 ±0.59 ±0.92 ±0.87 September 10.09 5.85 8.87 8.33 5.92 4.95 6.18 5.14 ±0.80 ±2.33 ±0.52 ±0.74 ±0.69 ±0.63 ±0.59 ±0.75 October 9.48 8.32 7.36 6.10 6.34 4.22 4.93 3.67 ±0.58 ±0.99 ±0.50 ±0.79 ±0.76 ±0.93 ±0.65 ±1.33 November 9.03 7.78 5.92 5.38 6.27 2.98 5.23 4.02 ±0.59 ±1.24 ±0.92 ±0.88 ±0.45 ±0.58 ±0.95 ±1.57 December 8.65 7.64 4.78 4.50 6.61 3.53 3.83 2.95 ±0.35 ±0.95 ±0.96 ±1.04 ±0.71 ±1.58 ±1.34 ±1.10 Average differences in the morning surface and bottom dissolved oxygen levels in the ring tank was 1.14 ± 1.25 mg/L over the duration of this study. The difference in the average afternoon surface and bottom DO levels was 1.64 ± 1.78 mg/L. The only extended period where pronounced differences in surface and bottom DO levels were observed were over summer months from October through to March in both 2002 and 2003. In both years these differences were greatest for afternoon readings. During this period, the afternoon surface water DO levels averaged 7.85 ± 2.04 mg/L compared to the bottom readings that averaged 3.97 ± 1.37 mg/L. This equates to an average difference in the daily surface and bottom DO levels of 3.85 ± 2.39 mg/L. Although low over summer, the DO levels at the floor of the ring tank increased from 4.73 ± 1.06 mg/L in March 2003 to 4.98 ± 0.78 mg/L and 5.73 ± 1.24 mg/L in April and May respectively of that year. Afternoon DO levels followed the same pattern as morning DO levels but afternoon values were typically higher than those observed in the morning (Table 3.3.3). In 30 of the 41 months where comparisons were possible, the surface DO levels were higher in the afternoon than in the morning. The FL readings for DO in the afternoons were only higher than the morning values in 16 of the 41 months. 3.3.2.2 Water Temperature Average water temperatures fluctuated on a seasonal basis peaking in the months of January and February of each year. The highest observed water temperature was 33.1ºC recorded in surface waters in the afternoon of 15/01/04. February 2004 had the highest average monthly morning and afternoon surface temperatures with values of 27.22 ± 1.50 ºC and 29.30 ± 1.66 ºC (Table 3.3.4 and 3.3.5). July and August were the coldest months in this study. The coldest temperature of 10.5ºC was recorded in the surface waters and the floor of the ring tank on the 07/0702. In that month the morning surface and floor water temperatures averaged 11.11 ± 0.49 ºC and 10.98 ± 0.40 ºC. These were the lowest average monthly water temperatures recorded in this study. 11
Page 1: Integrated Agri-Aquaculture Demonst
Page 4 and 5: © 2009 Rural Industries Research a
Page 6 and 7: Acknowledgments The authors would l
Page 8 and 9: Contents Foreword .................
Page 10 and 11: Table 4.3.11 Table 4.3.12 Table 4.3
Page 12 and 13: Executive Summary What the report i
Page 14 and 15: crop. This is much higher than simp
Page 16 and 17: documented such waters types as bei
Page 18 and 19: 2. Demonstration Farm 2.1 Backgroun
Page 20 and 21: Figure 2.2.3 Net cages used for sil
Page 22 and 23: 3. Water Use and Quality 3.1 Backgr
Page 26 and 27: Table 3.3.3 Average monthly afterno
Page 28 and 29: 169 165 161 157 153 149 145 141 137
Page 30 and 31: In February 2001, enough water was
Page 32 and 33: 4. Production Systems and Growth 4.
Page 34 and 35: Figure 4.2.3 The first 7m 3 floatin
Page 36 and 37: Figure 4.2.7 Uplift, baffle board a
Page 38 and 39: float to prevent drowning of air br
Page 40 and 41: Figure 4.2.13 Raceway push gate gra
Page 42 and 43: Table 4.3.1 Number and volume of ne
Page 44 and 45: Table 4.3.3 The length of culture p
Page 46 and 47: Stock retention was also high in th
Page 48 and 49: Table 4.3.10 The length of culture
Page 50 and 51: 4.3.5 Disease Detection and Treatme
Page 52 and 53: The average rate of growth for silv
Page 54 and 55: R E Figure 4.4.1 Existing (E) and r
Page 56 and 57: 5. Pesticide Monitoring and Residue
Page 58 and 59: 5.2.1.1 Pesticide Application and U
Page 60 and 61: prior to the commencement of the tr
Page 62 and 63: 5.4.2 Pesticide Bio-concentration a
Page 64 and 65: 0.4 0.35 0.3 0.25 ug/L 0.2 0.15 0.1
Page 66 and 67: There were no detections of endosul
Page 68 and 69: While further expansion of the inte
Page 70 and 71: 7. General Discussion The integrati
Page 72 and 73: Appendix Floating Raceway Technolog
Page 74 and 75:
Why Raceways? McVeigh Brothers P/L
Page 76:
Alternative but Adaptable System Mc
Page 79 and 80:
Water Flow (eddy) Flow (cm/sec) 35
Page 81 and 82:
End gates - changeable 67
Page 83 and 84:
35 g average fish - 3200 each 120 g
Page 85 and 86:
Paul McVeigh Mark Fantin Doug Young
Page 87 and 88:
Das, B., Sharif, Y., Khan, K., Das,
Page 89 and 90:
Müller , J.F., S Duquesne, Jack. N
Page 91:
Integrated Agri-Aquaculture Demonst
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