Aquaponics (s.l.) Production of Spearmint (Mentha spicata) with African Catfish (Clarias gariepinus) in Northern Germany
Abstract
:1. Introduction
2. Materials and Methods
2.1. Experimental Facility and System Design
2.2. Fish Production and Feeding
2.3. Plant Production
2.4. Physical and Chemical Water Parameters
2.5. Mathematical and Statistical Analysis
3. Results
3.1. Fish and Plant Production
3.2. Physical and Chemical Water Parameters
3.3. Nutrient Ratios and Biomass Relations
4. Discussion
4.1. Fish Production
4.2. Mint Production
4.3. Nutrient Ratios and Biomass Relations
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Parameters | Extensive (EAU) | Intensive (IAU) | p | ||||
---|---|---|---|---|---|---|---|
Initial Parameters | |||||||
Tanks | 1, 4, 7 | 2, 5, 8 | 3, 6, 9 | 1, 4, 7 | 2, 5, 8 | 3, 6, 9 | - |
Date of Stocking | 28 September 2015 | 17 August 2015 | 17 July 2015 | 28 September 2015 | 17 August 2015 | 17 July 2015 | - |
Day of Grow Out (d) 1 | 74 | 32 | 1 | 74 | 32 | 1 | - |
Individual Weight (g) | 275.0 | 275.0 | 275.0 | 275.0 | 275.0 | 275.0 | - |
Fish Number (no) | 105 | 105 | 105 | 420 | 420 | 420 | - |
Biomass Weight (kg) | 28.9 | 28.9 | 28.9 | 115.5 | 115.5 | 115.5 | - |
Stocking Density (kg/m3) | 7.6 | 7.6 | 7.6 | 30.6 | 30.6 | 30.6 | - |
Final Parameters | |||||||
Date of Harvest | 29 March 2016 | 26 January 2016 | 24 November 2015 | 29 March 2016 | 26 January 2016 | 24 November 2015 | - |
Day of Grow Out (d) 2 | 257 | 194 | 131 | 257 | 194 | 131 | - |
Duration Grow Out (d) | 156.3 ± 23.0 a | 156.3 ± 23.0 a | 1.000 | ||||
Individual Weight (g) | 1526.6 ± 284.0 a | 1458.8 ± 222.5 a | 0.436 | ||||
Mean Fish Number (no) | 33.7 ± 2.2 b | 127.2 ± 8.8 a | 0.001 | ||||
Survival (%) | 96.2 ± 6.4 a | 89.8 ± 5.3 b | 0.024 | ||||
Stocking Density (kg/m3) | 40.6 ± 6.6 b | 146.8 ± 20.6 a | 0.001 | ||||
Total Weight (kg/tank) | 41.5 ± 8.3 b | 146.4 ± 25.9 a | 0.001 | ||||
Feed Input (kg/tank) | 38.6 ± 6.9 b | 141.2 ± 27.1 a | 0.001 | ||||
FCR | 0.94 ± 0.04 a | 0.96 ± 0.04 a | 0.164 | ||||
SGR (% d−1) | 1.09 ± 0.06 a | 1.07 ± 0.08 a | 0.545 |
Extensive (EAU) | Intensive (IAU) | |||||
---|---|---|---|---|---|---|
Tanks | 1, 4, 7 | 2, 5, 8 | 3, 6, 9 | 1, 4, 7 | 2, 5, 8 | 3, 6, 9 |
Total Fish Biomass (kg) | ||||||
Beginning of the Experiment | 0 | 37 | 43 | 0 | 146 | 174 |
Day 74 before Stocking Tanks 1, 4, 7 | 0 | 68 | 75 | 0 | 242 | 270 |
Day 74 after Stocking Ranks 1, 4, 7 | 29 | 68 | 75 | 116 | 242 | 270 |
Parameters | Fertilizer (Control) | Extensive (EAU) | Intensive (IAU) | p-I 1 | p-II 1 | p-III 1 |
---|---|---|---|---|---|---|
Initial Parameters | ||||||
Initial Biomass (g/plant) | 2.7 ± 1.0 a | 2.3 ± 0.6 a | 2.8 ± 0.8 a | 0.831 | 0.979 | 0.725 |
Plant Height (cm) | 8.5 ± 1.7 a | 9.7 ± 2.0 a | 11.2 ± 2.4 a | 0.558 | 0.558 | 0.558 |
Leaf Length (cm) | 3.4 ± 0.6 a | 4.0 ± 0.5 a | 3.7 ± 1.5 a | 0.773 | 0.956 | 0.912 |
Leaf Width (cm) | 2.2 ± 0.3 a | 2.3 ± 0.3 a | 2.4 ± 0.7 a | 0.961 | 0.812 | 0.933 |
Final Parameters | ||||||
Plant Height (cm) | 38.4 ± 8.2 b | 45.2 ± 11.5 a | 51.0 ± 16.9 a | 0.009 | 0.001 | 0.109 |
Shoot Number (no) | 1.6 ± 0.7 b | 1.6 ± 0.6 b | 2.3 ± 1.2 a | 0.848 | 0.004 | 0.002 |
Leaf Area (cm2) | 5.7 ± 2.2 b | 5.6 ± 2.1 b | 10.9 ± 2.5 a | 0.977 | 0.001 | 0.001 |
Leaf Length (cm) | 5.5 ± 1.4 b | 5.4 ± 1.4 b | 8.6 ± 1.6 a | 0.997 | 0.001 | 0.001 |
Fresh Biomass (g/plant) | 120.6 ± 51.8 b | 165.5 ± 71.7 a | 190.7 ± 105.6 a | 0.034 | 0.003 | 0.621 |
Total Fresh Biomass (kg) * | 50.7 | 69.5 | 80.1 | - | - | - |
Fresh Cut Biomass (g/plant) ** | 11.2 ± 5.3 c | 17.4 ± 4.7 b | 31.8 ± 13.8 a | 0.006 | 0.001 | 0.005 |
Total Fresh Cut Biomass (kg) * | 4.7 | 7.3 | 13.4 | - | - | - |
Dry Biomass (g/plant) | 18.3 ± 7.4 a | 23.6 ± 12.4 a | 21.3 ± 14.2 a | 0.375 | 0.375 | 0.375 |
Parameters | Extensive (EAU) | Intensive (IAU) | p-Value |
---|---|---|---|
O2 (mg/L) | 7.1 ± 0.6 a | 4.9 ± 1.7 b | 0.001 |
O2 (%) | 88.6 ± 7.9 a | 60.1 ± 20.4 b | 0.001 |
Temperature (°C) | 26.7 ± 0.2 a | 25.8 ± 0.8 b | 0.001 |
pH | 7.2 ± 0.5 a | 6.6 ± 0.2 b | 0.001 |
Salinity (‰) | 0.5 ± 0.1 b | 0.6 ± 0.1 a | 0.001 |
Conductivity (µS/cm) | 952.3 ± 87.2 b | 1247.7 ± 128.9 a | 0.001 |
Redox Potential (mV) | 122.6 ± 32.4 a | 131.0 ± 26.7 a | 0.241 |
NH4+–N (mg/L) | 0.38 ± 0.23 b | 16.69 ± 5.11 a | 0.001 |
NO2−–N (mg/L) | 0.29 ± 0.17 a | 0.48 ± 0.54 a | 0.842 |
TON (mg/L) | 44.49 ± 8.73 b | 76.50 ± 12.53 a | 0.001 |
NO3−–N (mg/L) | 44.20 ± 8.69 b | 76.02 ± 12.37 a | 0.001 |
TDN (mg/L) | 44.87 ± 8.82 b | 93.19 ± 14.04 a | 0.001 |
PO43−–P (mg/L) | 3.06 ± 1.20 b | 7.06 ± 1.11 a | 0.001 |
Parameters | Fertilizer (Control) | Extensive (EAU) | Intensive (IAU) | p-I * | p-II * | p-III * |
---|---|---|---|---|---|---|
O2 (mg/L) | 8.3 ± 0.8 a | 5.1 ± 1.2 b | 2.8 ± 1.7 c | 0.001 | 0.001 | 0.001 |
O2 (%) | 87.4 ± 12.1 a | 56.1 ± 13.0 b | 31.2 ± 18.6 c | 0.001 | 0.001 | 0.001 |
Temperature (°C) | 18.9 ± 2.0 b | 20.9 ± 2.6 a | 20.8 ± 2.7 a | 0.001 | 0.001 | 0.900 |
pH | 8.1 ± 0.2 a | 7.3 ± 0.3 b | 7.4 ± 0.3 b | 0.001 | 0.001 | 0.622 |
Salinity (‰) | 0.4 ± 0.0 c | 0.5 ± 0.1 b | 0.6 ± 0.1 a | 0.001 | 0.001 | 0.001 |
Conductivity (µS/cm) | 673.7 ± 120.1 c | 821.0 ± 149.3 b | 1095.2 ± 122.4 a | 0.001 | 0.001 | 0.001 |
Redox Potential (mV) | 117.1 ± 102.4 a,b | 142.1 ± 136.9 a | 100.6 ± 46.1 b | 0.130 | 1.000 | 0.042 |
NH4⁺–N (mg/L) | 0.24 ± 0.31 c | 2.11 ± 3.44 b | 20.46 ± 6.53 a | 0.001 | 0.001 | 0.001 |
NO2−–N (mg/L) | 0.52 ± 1.11 b | 0.55 ± 0.30 a | 0.60 ± 0.49 a | 0.001 | 0.001 | 0.843 |
TON (mg/L) | 7.55 ± 2.12 b | 40.59 ± 12.40 a | 43.99 ± 17.94 a | 0.001 | 0.001 | 0.469 |
NO3−–N (mg/L) | 7.03 ± 1.95 b | 40.04 ± 12.38 a | 43.38 ± 17.85 a | 0.001 | 0.001 | 0.444 |
TDN (mg/L) | 7.79 ± 2.14 c | 42.70 ± 13.92 b | 64.45 ± 20.55 a | 0.001 | 0.001 | 0.001 |
PO43−–P (mg/L) | 3.44 ± 1.05 b | 3.30 ± 1.16 b | 7.98 ± 1.69 a | 0.392 | 0.001 | 0.001 |
N1/P2 | 2.4 ± 0.7 c | 13.4 ± 3.1 a | 8.2 ± 2.3 b | 0.001 | 0.001 | 0.001 |
Leaf Area/N 1 | 0.7 ± 0.3 a | 0.2 ± 0.1 b | 0.2 ± 0.1 b | 0.001 | 0.001 | 0.356 |
Leaf Area/P 2 | 1.6 ± 0.8 a | 2.2 ± 1.5 a | 1.6 ± 0.7 a | 0.148 | 0.148 | 0.148 |
Fresh Biomass/Leaf Area | 23.0 ± 10.5 a,b | 29.2 ± 19.8 a | 16.9 ± 11.0 b | 0.313 | 0.069 | 0.009 |
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Knaus, U.; Wenzel, L.C.; Appelbaum, S.; Palm, H.W. Aquaponics (s.l.) Production of Spearmint (Mentha spicata) with African Catfish (Clarias gariepinus) in Northern Germany. Sustainability 2020, 12, 8717. https://doi.org/10.3390/su12208717
Knaus U, Wenzel LC, Appelbaum S, Palm HW. Aquaponics (s.l.) Production of Spearmint (Mentha spicata) with African Catfish (Clarias gariepinus) in Northern Germany. Sustainability. 2020; 12(20):8717. https://doi.org/10.3390/su12208717
Chicago/Turabian StyleKnaus, Ulrich, Lisa Carolina Wenzel, Samuel Appelbaum, and Harry Wilhelm Palm. 2020. "Aquaponics (s.l.) Production of Spearmint (Mentha spicata) with African Catfish (Clarias gariepinus) in Northern Germany" Sustainability 12, no. 20: 8717. https://doi.org/10.3390/su12208717