NEW INSIGHTS INTO THE TIMESCALES AND ROUTING HISTORY OF THE LATE PLEISTOCENE MEGAFLOODS IN THE PACIFIC NORTHWEST

2017 ◽  
Author(s):  
Andrea Balbas ◽  
◽  
Aaron M. Barth ◽  
Peter U. Clark ◽  
Jorie Clark ◽  
...  
Keyword(s):  
Pacific Northwest ◽  
Late Pleistocene ◽  
The Pacific ◽  
History Of

Canopy disturbances over the five-century lifetime of an old-growth Douglas-fir stand in the Pacific Northwest

2002 ◽  
Vol 32 (6) ◽  
pp. 1057-1070 ◽  
Author(s):  
Linda E Winter ◽  
Linda B Brubaker ◽  
Jerry F Franklin ◽  
Eric A Miller ◽  
Donald Q DeWitt
Keyword(s):  
Pacific Northwest ◽  
Variable Density ◽  
Tsuga Heterophylla ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Old Growth ◽  
The Pacific ◽  
History Of ◽  
Horizontal Heterogeneity ◽  
Restoration Strategies

The history of canopy disturbances over the lifetime of an old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand in the western Cascade Range of southern Washington was reconstructed using tree-ring records of cross-dated samples from a 3.3-ha mapped plot. The reconstruction detected pulses in which many western hemlock (Tsuga heterophylla (Raf.) Sarg.) synchronously experienced abrupt and sustained increases in ringwidth, i.e., "growth-increases", and focused on medium-sized or larger ([Formula: see text]0.8 ha) events. The results show that the stand experienced at least three canopy disturbances that each thinned, but did not clear, the canopy over areas [Formula: see text]0.8 ha, occurring approximately in the late 1500s, the 1760s, and the 1930s. None of these promoted regeneration of the shade-intolerant Douglas-fir, all of which established 1500–1521. The disturbances may have promoted regeneration of western hemlock, but their strongest effect on tree dynamics was to elicit western hemlock growth-increases. Canopy disturbances are known to create patchiness, or horizontal heterogeneity, an important characteristic of old-growth forests. This reconstructed history provides one model for restoration strategies to create horizontal heterogeneity in young Douglas-fir stands, for example, by suggesting sizes of areas to thin in variable-density thinnings.

scholarly journals Ancient individuals from the North American Northwest Coast reveal 10,000 years of regional genetic continuity

2017 ◽  
Vol 114 (16) ◽  
pp. 4093-4098 ◽  
Author(s):  
John Lindo ◽  
Alessandro Achilli ◽  
Ugo A. Perego ◽  
David Archer ◽  
Cristina Valdiosera ◽  
...  
Keyword(s):  
Pacific Northwest ◽  
Late Pleistocene ◽  
North American ◽  
Archaeological Site ◽  
Northwest Coast ◽  
Genetic Lineage ◽  
Pacific Northwest Coast ◽  
The Pacific ◽  
Genetic Continuity ◽  
Low Coverage

Recent genomic studies of both ancient and modern indigenous people of the Americas have shed light on the demographic processes involved during the first peopling. The Pacific Northwest Coast proves an intriguing focus for these studies because of its association with coastal migration models and genetic ancestral patterns that are difficult to reconcile with modern DNA alone. Here, we report the low-coverage genome sequence of an ancient individual known as “Shuká Káa” (“Man Ahead of Us”) recovered from the On Your Knees Cave (OYKC) in southeastern Alaska (archaeological site 49-PET-408). The human remains date to ∼10,300 calendar (cal) y B.P. We also analyze low-coverage genomes of three more recent individuals from the nearby coast of British Columbia dating from ∼6,075 to 1,750 cal y B.P. From the resulting time series of genetic data, we show that the Pacific Northwest Coast exhibits genetic continuity for at least the past 10,300 cal y B.P. We also infer that population structure existed in the late Pleistocene of North America with Shuká Káa on a different ancestral line compared with other North American individuals from the late Pleistocene or early Holocene (i.e., Anzick-1 and Kennewick Man). Despite regional shifts in mtDNA haplogroups, we conclude from individuals sampled through time that people of the northern Northwest Coast belong to an early genetic lineage that may stem from a late Pleistocene coastal migration into the Americas.

scholarly journals INVESTIGATING THE EVOLUTIONARY HISTORY OF THE PACIFIC NORTHWEST MESIC FOREST ECOSYSTEM: HYPOTHESIS TESTING WITHIN A COMPARATIVE PHYLOGEOGRAPHIC FRAMEWORK

Evolution ◽  
2005 ◽  
Vol 59 (8) ◽  
pp. 1639-1652 ◽  
Author(s):  
Brayan C. Cartens ◽  
Steven J. Brunsfeld ◽  
John R. Demboski ◽  
Jeffrey M. Good ◽  
Jack Sullivan
Keyword(s):  
Hypothesis Testing ◽  
Pacific Northwest ◽  
Forest Ecosystem ◽  
Evolutionary History ◽  
Mesic Forest ◽  
The Pacific ◽  
History Of

scholarly journals Survey of Corylus Resistance to Anisogramma anomala from Different Geographic Locations

HortScience ◽  
2010 ◽  
Vol 45 (5) ◽  
pp. 832-836 ◽  
Author(s):  
Thomas J. Molnar ◽  
Joseph C. Goffreda ◽  
C. Reed Funk
Keyword(s):  
Genetic Diversity ◽  
Pacific Northwest ◽  
Host Resistance ◽  
Native Range ◽  
Geographic Locations ◽  
Pathogenic Variation ◽  
The Pacific ◽  
Complete Resistance ◽  
Anisogramma Anomala ◽  
History Of

Anisogramma anomala (Peck) E. Müller is the causal agent of the disease eastern filbert blight (EFB) of hazelnuts (Corylus spp.). Little is known of its genetic diversity and pathogenic variation. Most sources of host resistance have been identified in the Pacific Northwest, a region outside the native range of A. anomala believed to have limited diversity of the fungus due to a long history of quarantine and its relatively recent inadvertent introduction. In an attempt to investigate the pathogenic variation of A. anomala, 12 hazelnut genotypes that showed complete resistance in Oregon were inoculated with 12 isolates collected from across its native range. At the conclusion of the study, ‘Grand Traverse,’ ‘Ratoli’, OSU 541.147, OSU 495.072, and OSU 526.041 remained free of disease. ‘Closca Molla’, OSU 759.007, and OSU 587.044 were infected by most isolates. ‘Gasaway’ was infected by the Michigan isolate, which was also the only one to infect its offspring ‘Zimmerman’, although the lesion lacked sporulating stromata. Interestingly, ‘VR20–11’, another offspring of ‘Gasaway’, was infected by isolates from New Jersey, Minnesota, and Michigan. The Michigan isolate also caused the only signs of infection on OSU 408.040.

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