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51.
This study examined the use of Individual Transferable Quotas (ITQs) to effectively manage fishing impacts on all ecosystem components, as required under Ecosystem Based Fisheries Management (EBFM) principles. A consequence of changing from input controls to output-based (catch) management is that the control of the regulating authority tends to be reduced, which may affect the outcomes for ecosystem management. This study reviewed the use of input controls across six fishing methods in 18 ITQ fisheries, which have been independently accredited as ecologically sustainable by the Marine Stewardship Council (12 fisheries) or under Australian environmental legislation for Wildlife Trade Operation (six fisheries). Input controls were retained across a range of ITQ fisheries, with non-selective fisheries such as trawl, gillnet and line employing more input controls than selective fisheries such as purse-seine, pot/trap and dredge. Further case-studies confirmed the widespread and recent use of input controls (spatial and temporal closures) with the aim of managing ecosystem impacts of fishing. The retention of input controls, particularly closures affects the security (quality of title) characteristic of the fishing use right and the theoretical ability of fishers to manage their right for their future benefit. The security characteristic is weakened by closures through loss of access, which undermines industry trust and incentive for long-term decision making. By reducing the security of ITQs, individual fisher incentives and behaviour may separate from societal objectives for sustainability, which was one of the foremost reasons for introducing ITQ management. 相似文献
52.
Bridget L. Furness 《Marine pollution bulletin》1983,14(8):307-308
Small plastic particles were found in White-chinned Petrels and Great Shearwaters collected in the Benguela Current, but not in Sooty Shearwaters collected in the same region. The origin of these particles is unclear. They may have originated in the Antarctic or subantarctic, or, in the case of those found in the Great Shearwaters, in the North Atlantic. Plastic particle pollution of seabirds is an increasing phenomenon, and of concern in view of the possible damage caused to the birds. As such it should be carefully monitored. 相似文献
53.
Yun Huang Bridget R. Scanlon Jean-Philippe Nicot Robert C. Reedy Alan R. Dutton Van A. Kelley Neil E. Deeds 《Hydrogeology Journal》2012,20(4):783-796
Understanding groundwater-pumpage sources is essential for assessing impacts on water resources and sustainability. The objective of this study was to quantify pumping impacts and sources in dipping, unconfined/confined aquifers in the Gulf Coast (USA) using the Texas Carrizo-Wilcox aquifer. Potentiometric-surface and streamflow data and groundwater modeling were used to evaluate sources and impacts of pumpage. Estimated groundwater storage is much greater in the confined aquifer (2,200?km3) than in the unconfined aquifer (170?km3); however, feasibility of abstraction depends on pumpage impacts on the flow system. Simulated pre-development recharge (0.96?km3/yr) discharged through evapotranspiration (ET, ~37%), baseflow to streams (~57%), and to the confined aquifer (~6%). Transient simulations (1980–1999) show that pumpage changed three out of ten streams from gaining to losing in the semiarid south and reversed regional vertical flow gradients in ~40% of the entire aquifer area. Simulations of predictive pumpage to 2050 indicate continued storage depletion (41% from storage, 32% from local discharge, and 25% from regional discharge capture). It takes ~100?yrs to recover 40% of storage after pumpage ceases in the south. This study underscores the importance of considering capture mechanism and long-term system response in developing water-management strategies. 相似文献