Table 2 Emergy analysis of rice production systems in Saravan.
Input | Unit | Amount | Transformity | Source | Emergy/ha | Emergy/region | Percent |
---|---|---|---|---|---|---|---|
Renewable environmental inputs | |||||||
Solar energy | J | 1.96E+13 | 1.00 | Definition | 1.96E+13 | 1.15E+15 | 0.05 |
Wind kinetic energy | J | 7.51E+09 | 1.25E+03 | Campbell and Erban (2016) | 9.39E+12 | 5.35E+14 | 0.03 |
Rain chemical energy | J | 1.07E+09 | 2.25E+04 | Campbell et al. (2005) | 2.40E+13 | 1.37E+15 | 0.07 |
Rain geopotential energy | J | 2.55E+05 | 1.34E+04 | Campbell et al. (2005) | 3.42E+19 | 1.95E+11 | 0.00 |
River water | J | 8.93E+10 | 3.61E+04 | Campbell et al. (2005) | 3.22E+15 | 1.84E+17 | 9.03 |
Subtotal | 3.22E+15 | 1.84E+17 | 9.03 | ||||
Non-renewable environmental inputs | |||||||
Soil erosion | g | 1.50E+07 | 1.27E+09 | Brown and Bardi (2001) | 1.91E+16 | 1.09E+18 | 53.36 |
Subtotal | 3.18E+16 | 1.09E+18 | 53.36 | ||||
Economic inputs | |||||||
Human labor | J | 8.93E+08 | 2.22E+06 | Lu et al. (2009) | 1.98E+15 | 1.13E+17 | 5.55 |
Machinery | g | 6.86E+04 | 1.01E+10 | Campbell et al. (2005) | 6.93E+14 | 3.95E+16 | 1.94 |
Fuel | g | 1.78E+05 | 8.60E+04 | Bastianoni et al. (2009) | 1.53E+10 | 8.73E+11 | 0.00 |
Nitrogen fertilizer | g | 1.00E+05 | 3.09E+10 | Brandt-Williams (2002) | 3.09E+15 | 1.76E+17 | 8.66 |
Phosphorus fertilizer | g | 6.00E+04 | 6.55E+09 | Bastianoni et al. (2011) | 3.93E+14 | 2.24E+16 | 1.10 |
Potassium fertilizer | g | 5.00E+04 | 1.85E+09 | Bastianoni et al. (2011) | 9.25E+13 | 5.27E+15 | 0.26 |
Manure | g | 1.00E+07 | 2.96E+08 | Odum (1996) | 2.96E+15 | 1.69E+17 | 8.29 |
Pesticide | g | 5.00E+02 | 1.13E+10 | Jana and Chattopadhay (2005) | 5.65E+12 | 3.22E+14 | 0.02 |
Herbicide | g | 5.00E+02 | 1.13E+10 | Jana and Chattopadhay (2005) | 5.65E+12 | 3.22E+14 | 0.02 |
Fungicide | g | 5.00E+02 | 4.44E+03 | Bastianoni et al. (2011) | 2.00E+16 | 1.27E+18 | 0.00 |
Seedling | number | 5.80E+05 | 7.52E+09 | - | 4.21E+15 | 2.40E+17 | 11.78 |
Subtotal | 1.34E+16 | 7.65E+17 | 37.61 | ||||
Total | 3.57E+16 | 2.03E+18 | 100.00 | ||||
Output | |||||||
Grain yield | g | 2.50E+06 | |||||
Grain yield | J | 3.77E+10 | |||||
Straw yield | g | 1.10E+06 | |||||
Straw yield | J | 1.37E+10 |