A case study of life cycle impacts of small-scale fishing techniques in Thailand

Figures & data

Figure 1. System boundary of the considered Thai fisheries.

Notes: We include the production of vessels and gear and follow the catch to Rayong (including van that drives to Rayong), but neglect other processes after the fish has reached the market, such as further transport and export or processing.

Figure 2. Location of Muang Rayong District (red) within Rayong province (green) in Thailand (grey).

Source: Based on data from GADM (2011).

Table 1. Life cycle inventories based on ecoinvent 3.2 for three fishing techniques from four different fishers from Thailand per FU (1 kg of landed catch)

Foreground	Background inventory	Crab gill-net	Fish trap (I)	Fish trap (II)	Squid trap
Boat	Roundwood, eucalyptus ssp. (SFM), under bark, u=50%, at forest road/TH U	1.03E-05	6.09E-06	1.06E-05	2.92E-05
	Acrylic varnish, 87.5% in H2O, at plant/RER U	2.26E-04	5.60E-04	4.67E-04	1.52E-03
	Alkyd paint, white, 60% in solvent, at plant/RER U	1.02E-04	1.01E-04	4.19E-04	0.00E+00
Engine	Steel, low-alloyed, at plant/RER U	1.40E-04	2.78E-04	1.55E-04	6.28E-04
	Cast iron, at plant/RER U	4.32E-04	8.56E-04	4.76E-04	1.93E-03
	Aluminum, primary, at plant/RER U	2.99E-05	5.91E-05	3.29E-05	1.34E-04
	Aluminium alloy, AlMg3, at plant/RER U	2.46E-05	4.88E-05	2.71E-05	1.10E-04
	Synthetic rubber, at plant/RER U	6.27E-06	1.24E-05	6.91E-06	2.80E-05
Gear	Nylon 6, at plant/ RER/ kg	8.77E-03	–	–	–
	Lead, primary, at plant/ GLO/ kg	7.02E-03	–	–	–
	Polyethylene, LDPE, granulate, at plant/ RER/ kg	4.39E-02	3.67E-04	8.65E-03	2.75E-03
	Polypropylene, granulate, at plant/ RER/ kg	4.39E-03	5.51E-04	2.10E-03	6.88E-03
	Roundwood, eucalyptus ssp. (SFM), under bark, u=50%, at forest road/TH U	–	4.45E-05	1.40E-04	2.50E-05
	Steel, low-alloyed, at plant/ RER/ kg	–	4.77E-03	7.86E-03	2.75E-03
	Concrete block, at plant/DE U	–	2.94E-03	8.39E-03	2.20E-02
	Polystyrene, general purpose, GPPS, at plant/RER U	–	–	–	1.38E-03
Fuel	Fuel	1.02E-01	1.76E-01	1.84E-01	7.92E-01

Notes: Data is based on the SW season (June-October). The allocation of the material required for the entire lifetime of the boat is accounted for per season (1/lifetime*tot. catch). LCIs for the other seasons can be found in the Supporting Information (Excel file).

Table 2. Total catch and catch of target species per season for the different techniques

Season	Crab gill-net	Squid trap	Fish trap (I)	Fish trap (II)
	Total catch [kg]
NE	557	1,453	1,731	1,203
Pre	437	1,377	1,417	1,567
SW	1,969	1,174	3,979	1,908
	Catch of target species [kg]
NE	401	1,414	1,385	1,203
Pre	96	1,355	1,141	1,567
SW	496	1,164	3,813	1,908

Notes: NE: northeast monsoon season (November-February), Pre: pre-monsoon season (March-May), SW: southwest monsoon season (June-October).The large total catch umbers for the crab gill-net are attributable to the catch of krill.

Figure 3. Results for four different techniques (blue: crab gill-net, orange: fish trap (I), grey: fish trap (II), yellow: floating squid trap) and different impact categories: (A) global warming potential, (B) fossil depletion potential, (C) freshwater eutrophication potential, (D) metal depletion potential, (E) human toxicity potential, (F) terrestrial acidification potential, G) ozone layer depletion potential.

Notes: NE: northeast monsoon season (November- February), Pre: pre-monsoon season (March-May), SW: south-west monsoon season (June-October).

Table 3. Total impacts at midpoint level for selected impact categories (see main text) per functional unit, averaged over the year

Impact category	Crab gill-net	Fish trap (I)	Fish trap (II)	Squid trap
Climate change [kg CO2 eq]	6.58E-01	3.84E-02	6.98E-02	5.01E-02
Ozone depletion [kg CFC-11 eq]	1.61E-09	1.49E-09	1.44E-09	8.99E-10
Terrestrial acidification [kg SO2 eq]	1.78E-03	1.09E-04	1.79E-04	1.20E-04
Freshwater eutrophication [kg P eq]	2.00E-05	1.56E-05	1.34E-05	7.52E-06
Human toxicity [kg 1,4-DCB eq]	4.40E-03	7.44E-03	5.79E-03	3.57E-03
Metal depletion [kg Fe eq]	3.38E-03	3.72E-02	3.20E-02	1.21E-02
Fossil depletion [kg oil eq]	2.69E-01	1.18E-02	2.88E-02	2.25E-02

Notes: Results for the different seasons are shown in the SI and Figure 3, fuel efficiency is shown in Table 5 (fuel is not included here).

Table 4. Relative contribution per season of the direct fuel emissions in relation to the total climate change impacts from the four artisinal fisher

	NE (%)	Pre (%)	SW (%)
Crab gill-net	87	38	56
Fish trap (I)	94	96	97
Fish trap (II)	89	88	91
Floating squid trap	98	97	98

Figure 4. Visual representation of the predominance of direct fuel use emissions in regards to global warming potential (GWP) per season per fisher.

Table 5. Fuel efficiency [l/kg total and target catch landed] of the different fishing techniques on a yearly average, as well as for the different seasons

Season	Crab gill-net	Fish trap (I)	Floating squid trap	Fish trap(II)
	For total catch
NE	0.61	0.26	0.66	0.23
Pre	0.28	0.33	0.6	0.15
SW	0.1	0.18	0.79	0.18
Average	0.33	0.26	0.68	0.19
	For target catch only
NE	0.85	0.33	0.68	0.23
Pre	1.28	0.41	0.61	0.15
SW	0.44	0.18	0.8	0.18
Average	0.86	0.31	0.7	0.19

Notes: NE: northeast monsoon, Pre: pre-monsoon, SW: southwest monsoon.

Global Administrative Areas (GADM). (2011). GADM database version 2.0. Retrieved from http://www.gadm.org/version2

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