ABSTRACT
Oceans provide critical ecosystem services, but are subject to a growing number of external pressures, including overfishing, pollution, habitat destruction, and climate change. Current models typically treat stressors on species and ecosystems independently, though in reality, stressors often interact in ways that are not well understood. Here, we use a network interaction model (OSIRIS) to explicitly study stressor interactions in the Chukchi Sea (Arctic Ocean) due to its extensive climate-driven loss of sea ice and accelerated growth of other stressors, including shipping and oil exploration. The model includes numerous trophic levels ranging from phytoplankton to polar bears. We find that climate-related stressors have a larger impact on animal populations than do acute stressors like increased shipping and subsistence harvesting. In particular, organisms with a strong temperature-growth rate relationship show the greatest changes in biomass as interaction strength increased, but also exhibit the greatest variability. Neglecting interactions between stressors vastly underestimates the risk of population crashes. Our results indicate that models must account for stressor interactions to enable responsible management and decision-making.
Subject(s)
Climate Change , Conservation of Natural Resources/methods , Ecosystem , Fisheries/statistics & numerical data , Fishes/physiology , Algorithms , Animals , Arctic Regions , Biomass , Fishes/classification , Ice Cover , Models, Theoretical , Oceans and Seas , Phytoplankton/physiology , Temperature , Ursidae/physiologyABSTRACT
STAZ is an interactive computer program that demonstrates statistical concepts, many of which cannot be readily demonstrated using conventional methods. Use of dynamic graphics encourages active engagement with challenging statistical concepts. The program consists of 13 graphical demonstrations, most of which allow for interactive participation by students. A detailed Help file with guided explanations accompanies each demonstration. STAZ is a multiple document interface program that makes full use of Windows features, such as tiling, links, and multitasking. Designed to be used as a supplement for any undergraduate statistics course, STAZ may be used by either instructors in class-room settings or students working independently.
