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High Latitude Changes In Ice Dynamics And Their Impact On Polar Marine Ecosystems, Mark A. Moline, Nina J. Karnovsky, Zachary Brown, George J. Divoky, Thomas K. Frazer, Charles A. Jacoby, Joseph J. Torres, William R. Fraser
High Latitude Changes In Ice Dynamics And Their Impact On Polar Marine Ecosystems, Mark A. Moline, Nina J. Karnovsky, Zachary Brown, George J. Divoky, Thomas K. Frazer, Charles A. Jacoby, Joseph J. Torres, William R. Fraser
Biological Sciences
Polar regions have experienced significant warming in recent decades. Warming has been most pronounced across the Arctic Ocean Basin and along the Antarctic Peninsula, with significant decreases in the extent and seasonal duration of sea ice. Rapid retreat of glaciers and disintegration of ice sheets have also been documented. The rate of warming is increasing and is predicted to continue well into the current century, with continued impacts on ice dynamics. Climate-mediated changes in ice dynamics are a concern as ice serves as primary habitat for marine organisms central to the food webs of these regions. Changes in the timing …
Estimation Of Base Temperatures For Nine Weed Species, Scott J. Steinmaus, Timothy S. Prather, Jodie S. Holt
Estimation Of Base Temperatures For Nine Weed Species, Scott J. Steinmaus, Timothy S. Prather, Jodie S. Holt
Biological Sciences
Experiments were conducted to test several methods for estimating low temperature thresholds for seed germination. Temperature responses of nine weeds common in annual agroecosystems were assessed in temperature gradient experiments. Species included summer annuals (Amaranthus albus, A. palmeri, Digitaria sanguinalis, Echinochloa crus-galli, Portulaca oleracea, and Setaria glauca), winter annuals (Hirschfeldia incana and Sonchus oleraceus), and Conyza canadensis, which is classified as a summer or winter annual. The temperature below which development ceases (Tbase) was estimated as the x-intercept of four conventional germination rate indices regressed on temperature, by repeated probit analysis, …