[1] Flood basalts are a potentially important host medium for geologic sequestration of anthropogenic CO 2 . Most lava flows have flow tops that are porous and permeable and have enormous capacity for storage of CO 2 . Interbedded sediment layers and dense low-permeability basalt rock overlying sequential flows may act as effective seals allowing time for mineralization reactions to occur. Laboratory experiments confirm relatively rapid chemical reaction of CO 2 -saturated pore water with basalts to form stable carbonate minerals. Calculations suggest a sufficiently short time frame for onset of carbonate precipitation after CO 2 injection that verification of in situ mineralization rates appears feasible in field pilot studies. If proven viable, major flood basalts in the United States and India would provide significant additional CO 2 storage capacity and additional geologic sequestration options in certain regions where more conventional storage options are limited.

No abstract

Chum salmon Oncorhynchus keta and fall chinook salmon O. tshawytscha spawned at separate locations in a side channel near Ives Island, Washington, in the Columbia River downstream of Bonneville Dam. We hypothesized that measurements of water depth, substrate size, and water velocity would not sufficiently explain the separation in spawning areas and began a 2‐year investigation of physicochemical characteristics of the hyporheic zone. We found that chum salmon spawned in upwelling water that was significantly warmer than the surrounding river water. In contrast, fall chinook salmon constructed redds at downwelling sites, where there was no difference in temperature between the river and its bed. An understanding of the specific factors affecting chum salmon and fall chinook salmon redd site selection at Ives Island will be useful to resource managers attempting to maximize available salmonid spawning habitat within the constraints imposed by other water resource needs.

No abstract

No abstract