Time filter

Source Type

Farm Loop, AK, United States

Root H.T.,U.S. Department of Agriculture | Geiser L.H.,U.S. Department of Agriculture | Fenn M.E.,U.S. Department of Agriculture | Jovan S.,U.S. Department of Agriculture | And 6 more authors.
Forest Ecology and Management | Year: 2013

Anthropogenic nitrogen (N) deposition has had substantial impacts on forests of North America. Managers seek to monitor deposition to identify areas of concern and establish critical loads, which define the amount of deposition that can be tolerated by ecosystems without causing substantial harm. We present a new monitoring approach that estimates throughfall inorganic N deposition from N concentration in lichens collected on site. Across 84 study sites in western North America with measured throughfall, a single regression model effectively estimated N deposition from lichen N concentration with an R2 of 0.58 and could be improved with the addition of climate covariates including precipitation seasonality and temperature in the wettest quarter to an R2 of 0.74. By restricting the model to the more intensively sampled region including Oregon, Washington, and California, the R2 increased to 0.77. Because lichens are readily available, analysis is cost-effective, and accuracy is unaffected by mountainous terrain, this method allows development of deposition estimates at sites across broad spatial and topographic scales. Our approach can allow land managers to identify areas at risk of N critical load exceedance, which can be used for planning and management of air pollution impacts. © 2013.

Carlson R.J.,University of Cambridge | Baichtal J.F.,Tongass National Forest
Geoarchaeology | Year: 2015

A predictive model for locating early Holocene archaeological sites in southern Southeast Alaska was developed based on shell-bearing raised marine deposits. Fieldwork included coring of select-raised marine strata, measuring their elevations, and radiocarbon dating the associated shell samples within the cores. A subset of the data was used to produce a relative sea-level curve spanning the Holocene. The relative sea-level curve suggests that sites favorable for habitation between 9200 and 7000 14C yr B.P. should be found 16-22 ± 1 m above present zero tide. The sea-level curve and new high-resolution digital elevation models allowed reconstruction of past shorelines at various elevations. Surveys to test the model found and recorded over 70 archaeological sites from present sea level up to 32 m above present zero tide. Eleven new sites were within the targeted elevation range and radiocarbon dated to 9280-6890 14C yr B.P. Initial investigations indicate these older sites are rich in microblade and pebble tool technology. The new early Holocene sites indicate more extensive early maritime settlement of Alaska than implied by previous studies and contribute to our understanding of the early movement of people into North America. © 2015 Wiley Periodicals, Inc.

Esslinger T.L.,North Dakota State University | Dillman K.L.,Tongass National Forest
Bryologist | Year: 2010

Physconia grumosa, a species previously known from Asia, is reported from Alaska, the Rocky Mountains (Colorado, New Mexico), New England (Maine) and the Great Lakes region (Michigan, Minnesota, Wisconsin, Ontario). This species is similar to P. detersa, differing primarily by the type of propagules formed along the lobe margins: granular to weakly coralloid isidia and few to many dorsiventral lobules instead of true soredia. A description of the species is provided and comparisons with similar species are given. © 2010 by The American Bryological and Lichenological Society, Inc.

"WASHINGTON -- The Supreme Court on Monday declined to hear a case brought by the state of Alaska over the so-called Forest Service “roadless rule,” ending a major long-running court battle over the state’s attempts to be exempt from the logging regulation. The state had asked the Supreme Court to consider reversing a lower-court decision that tossed Alaska’s “exemption” from a regulation barring road-building in protected forest areas. While the high court’s decision is a major setback for the state, a similar effort to overturn the rule is still brewing in another federal court. The roadless rule originally went into effect in 2001, at the end of the Clinton administration. It barred the Forest Service from building roads and cutting timber on 58.5 million acres nationwide. In Southeast Alaska, it set aside 9.3 million acres of the 17 million-acre Tongass National Forest and nearly all of the 5.4 million-acre Chugach National Forest. The state challenged the rule in court and settled with the Forest Service in 2003, when the George W. Bush administration agreed to craft an exemption for the Tongass National Forest. "

News Article
Site: phys.org

While the groups have won strong restrictions on logging of the Tongass National Forest, the nation's largest, they have been denied in their efforts to win federal protection for the wolf. This week, the U.S. Fish and Wildlife Service denied them again: The agency determined that the wolf, known as the Alexander Archipelago wolf, should not be listed as an endangered or threatened species. While the government agreed with conservationists that the wolf is declining in parts of its range and that loss of its habitat from logging is playing a role in that decline, it said the overall population of the wolf appears to be healthy. "Although the Alexander Archipelago wolf faces several stressors throughout its range related to wolf harvest, timber harvest, road development, and climate-related events in southeast Alaska and coastal British Columbia, the best available information indicates that populations of the wolf in most of its range are likely stable," the Fish and Wildlife Service announced Tuesday. Named for a collection of remote islands, the wolf actually ranges across much of heavily forested mainland southeast Alaska and the coast of British Columbia in Canada. Conservationists pressing for its protection have focused on wolves in the archipelago, which includes on Prince of Wales Island, an expanse of nearly 2,600 square miles with about 6,000 people. Part of Prince of Wales is being logged under one of the largest timber sales in the Tongass in two decades, and estimates say the island could now have as few as 50 wolves, down from about 300 two decades ago. Logging can also reduce habitat for deer, a critical food source for the wolves. Conservationists built part of their argument on scientific evidence showing that wolves on the islands - an area the government calls "GMU 2," for Game Management Unit 2 - are genetically distinct from those roaming the mainland. The government agreed there are differences but said they were not strong enough to warrant listing the island wolves as a distinct species. The best available genetic data "do not indicate that the GMU 2 population harbors significant adaptive variation, which is supported further by the fact that the GMU 2 population is not persisting in an unusual or unique ecological setting," the government concluded. Bruce Dale, the director of the division of wildlife within the Alaska Department of Fish and Game, which argued against a listing, said the state was committed to protecting the wolf through improved forest management and hunting practices and other means. Despite the declines, he said wolves and deer on the islands remain abundant relative to other parts of the range. "That doesn't mean they weren't more abundant before," he said. The decision was a victory for the region's remaining timber industry. Only one large sawmill remains on Prince of Wales Island. The Fish and Wildlife Service said it expects wolves on the island to decline further in the next 30 years from "the cumulative effect of stressors." "However, wolves here constitute only 4 percent of the range of the Alexander Archipelago wolf and 6 percent of its current estimated total population. Therefore, negative population impacts on these islands will likely not affect the rangewide population in a significant way," the agency said. Explore further: Summit to weigh endangered red wolf's plight as numbers drop

Discover hidden collaborations