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Recent climate-change research largely confirms the impacts on US ecosystems identified in the 2009 National Climate Assessment and provides greater mechanistic understanding and geographic specificity for those impacts. Pervasive climate-change impacts on ecosystems are those that affect productivity of ecosystems or their ability to process chemical elements. Loss of sea ice, rapid warming, and higher organic inputs affect marine and lake productivity, while combined impacts of wildfire and insect outbreaks decrease forest productivity, mostly in the arid and semi-arid West. Forests in wetter regions are more productive owing to warming. Shifts in species ranges are so extensive that by 2100 they may alter biome composition across 5-20% of US land area. Accelerated losses of nutrients from terrestrial ecosystems to receiving waters are caused by both winter warming and intensification of the hydrologic cycle. Ecosystem feedbacks, especially those associated with release of carbon dioxide and methane release from wetlands and thawing permafrost soils, magnify the rate of climate change. © The Ecological Society of America.

Hydrophobic hollow fiber membranes (HFM) are already in use in industrial and medical applications. The goal of this study concentrated on examining the usefulness of HFM in water treatment situations, especially the presence of methyl tert-butyl ether (MTBE), which is frequently present at contaminated sites.

Comments on the need for producing ecologically-literate college students in the United States. Focus of conservation education on young children; Importance of college students in conservation education; Call for professional conservation biologists on educating children about environmental issues.

Increasing groundwater contamination with methyl tert-butyl ether (MTBE) requires more efficient remediation technologies. Accurate measurement of MTBE's air-water partitioning coefficient (Henry's law constant, H) is important for the design and optimization of removal efficiency for many treatment systems as well as for predicting its fate and transport. Previously published data for MTBE appear to have someunusual nonlinearity at lower temperatures (15-30 deg. C), and a wide range of values exists for dimensionless H at 25 deg. C, from 0.0216 to 0.1226 in the published literature. We measured H for MTBE usingheadspace solid-phase microextraction (SPME) and a static method that considers equilibrium partitioning in a closed system, for temperatures between 15 and 40 deg. C. To validate our methods, we measured Hfor benzene, toluene, and trichloroethylene and compared our resultsto previously published values, with excellent agreement. The Arrhenius plot for MTBE indicates that ln(HMBTE) = 6.85 -2,900 T-1, with T in K. At 25 deg. C, HMBTE = 0.0555 +/- 0.0122. [ABSTRACT FROM AUTHOR]