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DocumentOther documentGlobal spatio-temporal patterns in tropical tuna purse seine fisheries on drifting fish aggregating devices (DFADs): Taking a historical perspective to inform current challenges 2013
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No results found.This study provides a historical overview of the use of drifting fish aggregating devices (DFADs) in purse seine fisheries since the early 1990s, using global tu fisheries datasets from the four tu Regiol Fisheries Magement Organizations (RFMOs). Tropical tu purse seine fisheries typically target large yellowfin (Thunnus albacares) and bigeye (Thunnus obesus) tus on free-swimming schools and skipjack (Katsuwonus pelamis) and juveniles of yellowfin and bigeye associated with drifting objects. DFA Ds have ebled global skipjack catches to markedly increase, and have also introduced major scientific issues for all tu-RFMOs. In particular, they have strongly modified the fishing strategies of purse seiners that fish on a combition of free-swimming and DFAD-associated schools. Consequently, the cumulated search time traditiolly used to quantify nomil fishing effort to assess the status of tu stocks is inconsistent and cannot be used to derive time series of abundance indices from catch-per-un it of-effort (CPUE). In addition, the lack of information available on the construction, deployment, and use of DFADs has prevented effective monitoring of the fishing pressure over the last two decades exerted by purse seine fleets using this fishing mode. Juveniles of tropical tus represent a substantial proportion of purse seine catch on DFADs in the three oceans, which has raised particular concern for some bigeye stocks that have been subject to overfishing in the past. Catches of juvenile tus by DFAD fishing may also result in a decrease in recruitment for fisheries that target adult tus such as longliners. In addition, some demographic parameters of tus and other species associated with DFADs may be affected by the resultant habitat modification arising from the widespread deployment of DFADs. Evidence in the literature and provided by the ratio-estimator method suggest that fishing DFAD-associated schools may result in about 100 000 t of bycatch and discards annually. In additi on, there is further potential for ghost fishing related mortality of sensitive species such as marine turtles and pelagic sharks. In this context and following a precautiory approach, we filly discuss the increasing need for all tu-RFMOs to reduce, or at least monitor and control, the use of DFADs to mitigate their adverse effects not only on yellowfin and bigeye stocks but also on open-ocean ecosystems. -
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MeetingMeeting documentThe use of artificial fish aggregating devices by the French tropical tuna purse seine fleet: Historical perspective and current practice 2014
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Book (series)Technical reportConservation agriculture in China
Innovations, investment opportunities and challenges
2023Also available in:
While the agricultural production in China has made great achievements, it is also facing challenges affecting the sustainable development of agriculture. Conservation agriculture (CA) is a farming system that promotes minimum soil disturbance (i.e., no-tillage and direct seeding), maintenance of a permanent soil cover (mulch or cover crops), and diversification of plant species (crop rotations that include leguminous species). CA has been adopted in more than 100 countries worldwide and has become one of the most effective and widely used farming systems and technology for dryland agriculture. The adoption of CA can bring agronomic, environmental and economic benefits, and is of great significance to the development of green agriculture in China. This publication focuses on the development path, opportunities and challenges, development suggestions, technology and equipment, experiences, case studies and future scenarios for CA in China aiming to support the extension and adoption of CA in China and globally. This publication is part of the Country Investment Highlights series under the FAO Investment Centre's Knowledge for Investment (K4I) programme. -
Book (series)Technical studyClimate-smart agriculture in China
From policy to investment
2023Also available in:
Climate-smart agriculture (CSA) is a comprehensive system that requires thorough consideration of local climate, natural environment, market demand, economic and cultural environment. FAO introduced CSA at the Hague Conference on Agricultural, Food Security and Climate Change in 2010 and has been strongly supporting it since then. The development of CSA in China contributes to reaching its carbon peak by 2030 and carbon neutrality in China by 2060. This publication introduces China's CSA development and provides policy proposals. It contains four sections: the background and development status of China's CSA; practices and achievements of China's CSA, including analysing case studies such as the China Climate-Smart Staple Crop Production project funded by the Global Environment Facility (GEF); opportunities and challenges facing China's CSA; and national policy proposals and investments that include local schemes and smallholders for China's CSA. It is critical for China to strengthen its cooperation with international organizations to explore innovative, efficient, resilient, and sustainable climate-adaption technologies for the transformation of agrifood systems. This publication is part of the Country Investment Highlights series under the FAO Investment Centre's Knowledge for Investment (K4I) programme. -
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