Trophic interactions in northern Chile upwelling ecosystem, year 1997

摘要: A food web model is constructed to describe predator-prey interactions, community structure and trophic flows in northern Chile upwelling ecosystem (18°20'S, 24°S), for the year 1997. The built using Ecopath with Ecosim software version 6.4, encompasses 21 functional groups, ranging from primary producers (phytoplankton) top predators (birds marine mammals), principal fishing resources fishery. Input parameters required build were gathered specialized literature, grey literature our own estimates. results indicated that total biomass (BT) was estimated at 624.7 ton km -2 . combined of small pelagic fish represented 26% BT, while demersal only 0.1% BT. These highlight importance this system. Predation mortality resulted be main source mortality. Nevertheless, important anchovy, mackerel, common dolphinfish jack mackerel. mean level fishery as 3.7, landings sustained mainly by anchovy. Primary production sustain (PPR) 7.5% calculated net production, which lower than PPR estimates other ecosystems. average transfer efficiency 18%, range (10-20%) informed Results indicate 1997 characterized being a system far maturity, dominated terms realm.