Emergy assessment of tilapia cage farming in a hydroelectric reservoir

Garcia, Fabiana; Kimpara, Janaina Mitsue; Valenti, Wagner C.; Ambrósio, Luís Alberto

doi:10.1016/j.ecoleng.2014.03.076

Cited by 35 publications

(34 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although the use of antibiotics in fish farming are regulated in Brazil (Quesada et al., ), enforcement is not always the rule, especially in the least developed areas, raising multiple issues, including the use of illicit antibiotics (Hashimoto et al., ). The concentration of tilapias in cages also increases waste in shallow reservoirs, which could lead to reservoir eutrophication (Starling, Lazzaro, Cavalcanti & Moreira, ), especially at the high stocking densities done in Brazil (100 kg of fish per m 3 ) (Garcia, Kimpara, Valenti & Ambrosio, ). Again, this also depends on cage density and their stocking, and on the reservoir depth and its connectivity with other water bodies.…”

Section: Resultsmentioning

confidence: 99%

Fisheries or aquaculture? Unravelling key determinants of livelihoods in the Brazilian semi-arid region

et al. 2017

View full text Add to dashboard Cite

In impoverished semi-arid regions in the world, reservoirs serve multiple purposes, including food provision through fisheries and aquaculture. Yet, the socio-economic benefits of promoting both activities remain unclear. We independently assessed the socio-economic benefits generated from fisheries and aquaculture, in two reservoirs in the Brazilian semi-arid region (June 2013 to June 2014). These reservoirs produced 27.75 ton of farmed tilapia over a year (USD Purchasing Power Parities[PPP] 88,778.73) and provided at least 16.5 ton of fish through fisheries (USD PPP 37,557.81), based on data from four farmer associations. Our input-output model revealed that the local economy depends on both activities, which, therefore, contribute similarly to providing goods and services to different branches. Aquaculture generated much higher revenues (seven times) than fisheries, but also much higher losses (the most successful farm yielded an average income of USD PPP 592.41 monthly). Still, there were no statistical differences in income among the compared associations. Fisheries provided very but guaranteed income (USD PPP 311.02 AE 82.94) and employed over three times as many people and contributed much more (>3 times) to food security than aquaculture. Encouraging aquaculture through specific policies while overlooking fisheries is not advisable because poor fishers would not be able to deal with unpredictable outcomes and it would put their food security at risk. However, if initial external support is provided to fishers in order to buffer large losses, aquaculture could represent a way out of poverty by generating an opportunity for larger gains, as long as potential negative ecological impacts of aquaculture are accounted for.

show abstract

Section: Resultsmentioning

confidence: 99%

Fisheries or aquaculture? Unravelling key determinants of livelihoods in the Brazilian semi-arid region

et al. 2017

View full text Add to dashboard Cite

show abstract

“…2). As verified by Garcia et al (2014), this trend shows that tilapia cage farming is dependent on the economic inputs, and the feed is mainly responsible for this because it has high transformity value and, in intensive aquaculture, is used in large amounts (Ayroza et al, 2011;Garcia et al, 2013Garcia et al, , 2014. The feed impact on aquaculture sustainability is poorly documented by emergy assessment.…”

Section: Discussionmentioning

confidence: 99%

“…In this way, it becomes necessary to guide aquaculture farmers to adopt practices that attend to this concept of sustainability to maximize productive efficiency, but also to reduce losses, costs, and negative environmental impacts, increasing the possibility of success over time (Wilfart et al, 2013). One strategy for this is to reduce dependence on feed (Garcia et al, 2014), for example, by reducing the stocking density (Garcia et al, 2013) and using periphyton as a natural food (Garcia et al, 2016). The periphyton community develops naturally on submerged substrates like rocks, woods, plants and sediments.…”

Section: Introductionmentioning

confidence: 99%

Improving the sustainability of tilapia cage farming in Brazil: An emergy approach

David

Pinho

Garcia

2018

Journal of Cleaner Production

View full text Add to dashboard Cite

a b s t r a c tThe accelerated and disorderly expansion of aquaculture can lead to economic, social, and environmental problems. In this sense, it is necessary to prioritize the adoption of practices that aim for sustainable production. The aims of the present study were to identify the contributions from nature and economy in the system of tilapia cage farming. In addition, emergy accounting was utilized to evaluate whether the use of periphyton as a complementary food and the reduction of storage density improve the sustainability of this production system. Three different production managements were evaluated and compared: using traditional stocking density adopted by farmers (80 kg/m 3 ) with 100% of the daily recommended feed and without substrates for periphyton (TRAD); traditional stocking density (80 kg/ m 3 ) with 50% of the daily recommended feed and with substrates for periphyton (TDS); lower density (40 kg/m 3 ) with 50% of the daily recommended feed and with substrates for periphyton (LDS). We calculated using emergy accounting the transformity (Tr), renewability (%R), emergy yield ratio (EYR), emergy investment ratio (EIR), emergy loading ratio (ELR), emergy exchange ratio (EER), and emergy sustainability index (ESI) of the distinct production managements. The results showed that tilapia cage farming is highly dependent on resources from economy, and feed is mainly responsible for this. Thus, the decrease in stocking density and feed rate, combined with the use of periphyton, improved all emergy indices evaluated. This occurred because there was a decrease in the use of resources from economy and increase in the use of renewable natural resources. The study shows through the emergy accounting that the use of periphyton to feed cultured fish combined with a reduction in artificial feed use and a decrease in the stocking density should be encouraged to promote the sustainability on tilapia cage farming.Published by Elsevier Ltd.

show abstract

“…However, aquaculture is an anthropic activity that has not easily met the requirements of environmental sustainability (Eler & Millani 2007), especially when conducted in large reservoirs (Deus et al 2013, Garcia et al 2014. One of the environmental changes more commonly associated with freshwater aquaculture is eutrophication (Black 2000).…”

Section: Introductionmentioning

confidence: 99%

“…However, this activity can have a significant impact on aquatic environments (Garcia et al 2014, Li et al 2014, and minimizing these risks requires planning, legislating compliance, and managing and monitoring the environmental quality of the fish farms (Nyanti et al 2012, Ling et al 2013, Ramos et al 2013.…”

Section: Introductionmentioning

confidence: 99%

Environmental characterization and impacts of fish farming in the cascade reservoirs of the Paranapanema River, Brazil

Neto¹,

Nocko²,

Ostrensky³

2015

Aquacult. Environ. Interact.

View full text Add to dashboard Cite

The goal of this study was to characterize current water quality, simulate water quality in 8 large artificial reservoirs occurring along the course of the Paranapanema River, Brazil, and estimate fish production in the region to assess the impacts of this production on the local aquatic environment. Primary data describing the bottom sediments and water quality, and time series recorded between 2001 and 2011 were used. Water quality was modeled to simulate the trophic state index (TSI) for each reservoir, and 37 fish cage farms along the length of those reservoirs were identified. Only one-third of these farms had environmental licensing for regular operations. The potential increase in fish production was estimated to exceed 250% in the short to medium term. The concentrations of nutrients (organic matter, nitrogen, and phosphorus) present in the bottom sediment beyond areas of fish production were similar to those found in areas distant from the fish farms. The TSI results indicated that the reservoirs could be classified between oligotrophic and mesotrophic. The few eutrophied areas represented approximately 1% on average of the total area of the reservoirs. The reservoirs of the Paranapanema River have adequate water quality standards for aquaculture, and there is no indication that this activity is currently causing significant impacts to the overall aquatic environment in each reservoir. Nevertheless, caution is required when selecting areas for new fish farms to avoid areas that are more susceptible to eutrophication.

show abstract

Emergy assessment of tilapia cage farming in a hydroelectric reservoir

Cited by 35 publications

References 18 publications

Fisheries or aquaculture? Unravelling key determinants of livelihoods in the Brazilian semi-arid region

Fisheries or aquaculture? Unravelling key determinants of livelihoods in the Brazilian semi-arid region

Improving the sustainability of tilapia cage farming in Brazil: An emergy approach

Environmental characterization and impacts of fish farming in the cascade reservoirs of the Paranapanema River, Brazil

Contact Info

Product

Resources

About