LCA of Biofloc Shrimp Farming Technology
Transcription
LCA of Biofloc Shrimp Farming Technology
From its beginning in the 1920’s, aquaculture in Malaysia has developed quickly and is now an important activity. With long coastlines, vast expanses of coastal belt, inland areas, and water bodies suitable for aquaculture development, aquaculture provides the best avenue of increasing local production for food security and increasing export revenues. The shrimp aquaculture has great economic and social importance, and also reduce pressure on overexploited wild stocks. Various culture systems: Mud flat culture Freshwater pond culture Brackish water pond culture Long-line culture of seaweed Marine cage culture of fish Raft culture of mussel and oyster Mining pool culture of freshwater fishes Freshwater cage culture Tank culture of freshwater fishes (FAO, 2014) • Marine shrimp trapping ponds were first developed 1930’s in Johore • Semi-intensive culture of shrimp was developed in 1970’s Johore • The whiteleg shrimp, Penaeus vannamei, began production when the marine shrimp production 2001’s showed a sharp increase of almost 70% • The aquaculture sector recorded an annual growth rate of about 10%, mainly the cultures in shrimp, 2014’s marine fish and high value freshwater fish There are significant differences between and within countries regarding the levels of production intensity and yields, farm numbers and their sizes, and the various types of resources utilized. Shrimp farms are classified into: Extensive - low stocking densities - little/no external nutritional inputs -tidal water exchange -shrimp yields of less than 500 kg/ha/yr Semi-intensive - using fertilizers & supplemental feeding - intermediate stocking - occasional pumping of water - shrimp yields of 1-2 tonnes/ha/yr Intensive - high stocking density - formulated complete feeds - aeration and water pumping - shrimp yields of more than 2 tonnes/ha/yr Over the years, the shrimp farming has acquired the reputation of being destructive (being linked to mangrove clearing) and unsustainable. Causing negative impacts on the environment, aquatic ecosystems and human lives in coastal areas including biodiversity depletion, eutrophication, land modification and food insecurity (Diana, 2009; Naylor et al., 2000). The release of nutrient-rich effluent water on receiving streams (Porchas and Cordova, 2012). The BFT for shrimp production has been proposed as a sustainable practice, capable of reducing environmental impacts and preventing pathogen introduction. Biofloc is a protein rich aggregate of organic material and micro-organisms including bacteria, protozoa, algae, and other suspended organisms (Hargreaves 2006). The microbial community associated with BFT not only detoxifies nutrients, but also can improve feed utilization and animal growth. Bioflocs are assumed to enhance shrimp immunity because they consume the bioflocs as additional food source (Kim et al., 2014). Less or zero water exchange Shrimp eat bacteria, the feed recycled Reducing viral disease outbreaks BFT Bacteria control water quality – no chemical used Organic residues accumulate Ideal conditions for bacteria A decision-support tool for both policy makers and industry to assess cradle-to-grave impacts of all the stages in a product’s life and processes (Hanafiah MM, 2013). Compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product system throughout its life cycle. This establishes an environmental profile of the system. Specific research questions are including: What are the environmental impacts identified in each phase of the life cycle in shrimp farming activities? How LCA can be used to maintain and conserve the ecosystems and the environment in the shrimp farming industry? To identify the impact on ecosystem health caused by shrimp farming activities by measuring the level of eutrophication, acidification and energy consumption in shrimp farming phase. To assess the reliability of the Life Cycle Assessment in identifying environmental performance at every phase of shrimp farming activities. To develop a Life Cycle Assessment model for a biofloc shrimp farming technology. 1. Goal and scope definition Aim: Identification of the impacts on ecosystem health caused by shrimp farming activities. Assessment of the environmental performance at every phase of shrimp farming process. Development of an LCA model for a biofloc shrimp farming technology. Functional unit: 1 live weight tonne shrimp System boundaries: Gate-to-gate 2. Data inventory (LCI) Foreground data from the shrimp production cycle in 2015 Background data from secondary data supplemented by SimaPro (version 7.3) 3. Impact assessment (LCIA) Stressors: GHG emissions Eutrophication Solid waste Primary energy use Method: Eco-indicator 99 4. Interpretation Limitation Sensitivity analysis Uncertainty analysis Recommendation A complete gate-to-gate assessment of the biofloc shrimp farming will be carried-out using a comprehensive LCA approach. This research will develop a clear and comprehensive conceptual framework to analyze the environmental impacts of biofloc shrimp farming towards a green and sustainable aquaculture practice. The second kind of context is the practice of LCA: the decision-making and learning processes in which life cycle studies are carried out and where the environmental impact will be evaluated. The aim of investigations of these processes is to better understand how environmental footprint is used and perceived and how, or if, they can contribute to making life cycle data meaningful to those concerned. The third context type is related to methods development; it comprises different attempts to measure values, attitudes and opinion concerning environmental changes for the purpose of expressing the relative severity of such changes. Finally, a development of an LCA model of all processes included for shrimp farming activities.