55 research outputs found
Enhancing the ecosystem approach for the fishery for Antarctic krill within the complex, variable and changing ecosystem at South Georgia
The objective of the ecosystem approach to fisheries management is to sustain healthy marine ecosystems and the fisheries they support. One of the earliest implementations was in the Southern Ocean, where decision rules and stock reference points were developed for managing the Antarctic krill fishery, together with an ecosystem-monitoring programme intended to aid management decisions. This latter component has not been incorporated directly into management, so here, we consider variability in the krill fishery at South Georgia, relating it to physical and biological monitoring indices, finding sea surface temperature to be a key correlate with both annual catch and long-term biological indices. Some indices from krill predators showed significant positive relationships with krill harvesting in the preceding winter, presumably indicative of the importance of winter foraging conditions. We explore how ecological structure affects results, examining two monitoring sites 100âkm apart. Results suggest different biological conditions at the two sites, probably reflecting different scales of ecosystem operation, emphasizing that an appreciation of scale will enhance krill fishery management. Finally, in reviewing different drivers of ecological change, we identify important additional monitoring that would help better reflect ecosystem status, improve the utility of CEMP, providing information necessary for the ecosystem approach at South Georgia
The Local Bubble and Interstellar Material Near the Sun
The properties of interstellar matter (ISM) at the Sun are regulated by our
location with respect to the Local Bubble (LB) void in the ISM. The LB is
bounded by associations of massive stars and fossil supernovae that have
disrupted natal ISM and driven intermediate velocity ISM into the LB interior
void. The Sun is located in such a driven ISM parcel. The Local Fluff has a
bulk velocity of 19 km/s in the LSR, and an upwind direction towards the center
of the gas and dust ring formed by the Loop I supernova remnant interaction
with the LB. When the ram pressure of the LIC is included in the total LIC
pressure, and if magnetic thermal and cosmic ray pressures are similar, the LIC
appears to be in pressure equilibrium with the local hot bubble plasma.Comment: Proceedings of Symposium on the Composition of Matter, honoring
Johannes Geiss on the occasion of his 80th birthday. Space Science Reviews
(in press
Levantamento florĂstico das macroalgas da baĂa de Sepetiba e adjacĂȘncias, RJ: ponto de partida para o Programa GloBallast no Brasil
Auroral Processes at the Giant Planets: Energy Deposition, Emission Mechanisms, Morphology and Spectra
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