Use of chemicals and biological products in Asian aquacultire and their potential environmental risks: a critical review
Rico, A. ; Satapornvanit, K. ; Haque, M.M. ; Min, J. ; Nguyen, P.T. ; Telfer, T. ; Brink, P.J. van den - \ 2012
Reviews in Aquaculture 4 (2012)2. - ISSN 1753-5123 - p. 75 - 93.
species sensitivity distributions - fresh-water - macrobrachium-rosenbergii - veterinary antibiotics - aquatic environment - malachite green - mangrove areas - shrimp ponds - toxicity - fish
Over the past few decades, Asian aquaculture production has intensified rapidly through the adoption of technological advances, and the use of a wide array of chemical and biological products to control sediment and water quality and to treat and prevent disease outbreaks. The use of chemicals in aquaculture farms has raised environmental concerns owing to their potential impacts on downstream aquatic ecosystems. Currently little is known about the environmental fate and effects of the chemicals used in Asian aquaculture. Consequently, we reviewed recent information on the use of chemical and biological products in the most important Asian aquaculture producing countries and briefly summarize their main potential environmental impacts. We provide an overview of the main factors controlling the use of these chemicals and describe the international risk assessment guidelines available for aquaculture chemicals. Finally, data gaps and research needs for their implementation in Asian countries are discussed. Our review aims to form a basis for developing environmental risk assessment studies of the chemicals used in Asian aquaculture.
Enhancing benefits from polycultures including tilapia (Oreochromis niloticus) within integrated pond-dike systems: A participatory trial with households of varying socio-economic level in rural and peri-urban areas of Bangladesh
Karim, M. ; Little, D.C. ; Verdegem, M.C.J. ; Telfer, T. ; Wahab, M.A. - \ 2011
Aquaculture 314 (2011)1-4. - ISSN 0044-8486 - p. 225 - 235.
resource-poor farmers - farming systems - aquaculture - fertilization - diversity - thailand - issues - nile
Linkages between the fish ponds and surrounding land for horticulture are a distinctive feature of farming households in Bangladesh. It was hypothesised that integration of fish ponds in integrated farming system enhances livelihoods and reduces poverty. The effects of introducing tilapia into existing integrated farming systems on the broader pond-dike system and associated livelihoods in rural and peri-urban settlements in central north (Mymensingh District) of Bangladesh were evaluated. Farmer participatory research carried out during June 2004 to March 2005 showed that production of fish could be substantially increased by increasing nutrient inputs rather than by stocking tilapia as an additional species. However, the ‘improved’ nutrient input applied by farmers was still well below the level required for optimal tilapia performance. Rural households benefited more than peri-urban households through enhanced direct consumption of fish and vegetables. In contrast, peri-urban households benefited more through cash sales of both fish and vegetables than rural households. Households with access to ponds, identified as relatively better-off and worse-off in the researched communities benefited equally selling and consuming fish and vegetable. Similar production levels of vegetable production between groups applying different fish culture practises suggesting that increased investment in fish production is complementary rather than competitive to vegetable production in integrated pond-dike farming systems. It was concluded that considerable potential exists to further develop pond-dike systems, which would improve livelihoods of both better-off and worse-off producers. Reference is made to the potential impacts of such changes in integrated pond-dike management if promoted more widely in Bangladesh.