scholarly journals Toward a better understanding of climate and human impacts on late Holocene fire regimes in the Pacific Northwest, USA

2018 ◽  
Vol 42 (4) ◽  
pp. 478-512 ◽  
Author(s):  
Megan K Walsh ◽  
Haley J Duke ◽  
Kevin C Haydon
Keyword(s):  
Pacific Northwest ◽  
Ponderosa Pine ◽  
Late Holocene ◽  
Human Impacts ◽  
Fire Severity ◽  
Fire Regimes ◽  
The Past ◽  
The Pacific ◽  
Clackamas County ◽  
Study Sites

In order to fully appreciate the role that fire, both natural and anthropogenic, had in shaping pre-Euro-American settlement landscapes in the Pacific Northwest (PNW), it is necessary to develop a more robust method of evaluating paleofire reconstructions. Here we demonstrate an approach that includes the identification of charcoal morphotypes (i.e. visually distinct charcoal particles), and incorporates both paleoecological and archaeological data sets, to more specifically determine both the nature of past fire regimes (i.e. fuel type and fire severity) and the likely ignition source of those fires. We demonstrate the usefulness of this approach by reconstructing the late Holocene fire and vegetation histories of Lake Oswego (Clackamas County), Oregon, and Fish Lake (Okanogan County), Washington, using macroscopic charcoal and pollen analysis of sediment cores. The histories were compared with climatic records from the PNW as well as archaeological, ethnographic, and historical records from the Lower Columbia River Valley and Southern Columbia Plateau cultural regions. Our results indicate that while centennial-to-millennial-scale climate change had limited influence on the fire regimes at the study sites during the past ∼3800 years, the use of fire by Native Americans for a variety of reasons, particularly after ca. 1200 calendar years before present (AD 750), had a far greater impact. Charcoal morphotype ratios also indicate that fires in the two watersheds were fundamentally different in their severity and impact, and led to major shifts in the forests and woodlands surrounding Lake Oswego, but helped maintain the ponderosa pine-dominated forest at Fish Lake. The elimination of fire from the two study sites during the past 100–300 years is likely the combined result of Euro-American contact and the arrival of disease in the PNW, as well as 20th-century fire suppression and grazing effects on fuel continuity, which has implications for future forest management and restoration efforts in the PNW.

The Windgrasses(AperaAdans., Poaceae) in North America

1992 ◽  
Vol 6 (2) ◽  
pp. 445-450 ◽  
Author(s):  
F. E. Northam ◽  
R. H. Callihan
Keyword(s):  
United States ◽  
North America ◽  
Pacific Northwest ◽  
Northeastern United States ◽  
Southern Ontario ◽  
Grass Seed ◽  
The Past ◽  
Winter Cereals ◽  
The Pacific ◽  
Additional Control

Two introduced windgrass species have become crop weeds in North America. Common windgrass is a major weed of winter cereals in Europe and was first documented in North America in the early 1800s. It is a weed of roadsides and waste areas in the northeastern United States and in winter grain fields of southern Ontario and Michigan. Interrupted windgrass was first reported in North America approximately 90 yr ago; it is adapted to more arid sites than common windgrass and is distributed predominantly in the northwestern U.S.A. During the past 10 to 15 yr, interrupted windgrass has adversely affected winter grain and grass seed producers in the Pacific Northwest due to additional control costs.

scholarly journals Past and Present Vulnerability of Closed-Canopy Temperate Forests to Altered Fire Regimes: A Comparison of the Pacific Northwest, New Zealand, and Patagonia

BioScience ◽  
2014 ◽  
Vol 65 (2) ◽  
pp. 151-163 ◽  
Author(s):  
Cathy Whitlock ◽  
David B. McWethy ◽  
Alan J. Tepley ◽  
Thomas T. Veblen ◽  
Andrés Holz ◽  
...  
Keyword(s):  
New Zealand ◽  
Pacific Northwest ◽  
Temperate Forests ◽  
Fire Regimes ◽  
The Pacific ◽  
Closed Canopy

scholarly journals Seeing Themselves: Jean Barman’s French Canadians, Furs, and Indigenous Women in the Making of the Pacific Northwest as a Resource for the Region’s People

2017 ◽  
Vol 27 (2) ◽  
pp. 130-135
Author(s):  
Stacy Nation-Knapper
Keyword(s):  
Pacific Northwest ◽  
Indigenous Communities ◽  
Indigenous Women ◽  
French Canadians ◽  
Cultural Encounters ◽  
The Past ◽  
Award Winning ◽  
The Pacific ◽  
Columbia River Plateau ◽  
Complicated Nature

Dr. Barman’s award-winning study is a resource to the Indigenous and non-Indigenous people of the Columbia River Plateau and the Pacific Northwest, an environmentally and culturally diverse region that now encompasses two countries, two provinces, three states, and many Indigenous communities. For Indigenous communities of the region, French Canadians, Furs, and Indigenous Women in the Making of the Pacific Northwest provides an important context of colonialism, global economics, and the complicated nature of cross-cultural encounters. For non-Indigenous communities, the book also encourages an appreciation for the complexities of history often overlooked by celebratory histories of colonization. French Canadians, Furs, and Indigenous Women in the Making of the Pacific Northwest is a resource in which people see themselves and their families in a complicated, accessible, and inspiring story of the past.

Late Holocene fluctuations of Stoppani Glacier, southernmost Patagonia

2020 ◽  
Vol 95 ◽  
pp. 56-64 ◽  
Author(s):  
Brian Menounos ◽  
Lyssa Maurer ◽  
John J. Clague ◽  
Gerald Osborn
Keyword(s):  
Pacific Northwest ◽  
Late Holocene ◽  
Response Times ◽  
Western Canada ◽  
Lateral Moraine ◽  
The Past ◽  
Significant Difference ◽  
Glacial Expansion ◽  
Age Range ◽  
The U.S

AbstractSome lateral moraines contain a rich record of Holocene glacial expansion. Previous workers have used such evidence to document glacial fluctuations in western Canada, Alaska, and the U.S. Pacific Northwest, but similar studies in Patagonia are uncommon. Here we report on the late Holocene behavior of Stoppani Glacier, a 75 km2 glacier sourced in the Cordillera Darwin, southernmost Patagonia. Based on radiocarbon-dated wood and organic material contained in the glacier's northeast lateral moraine, we infer that Stoppani Glacier advanced shortly before 3.8–3.6, at 3.2–2.8, 2.3–2.1, and 0.3–0.2, and possibly sometime before 1.4–1.3 and 0.8–0.7 cal ka BP. These advances culminated at 0.3–0.2 cal ka BP, when the glacier constructed a prominent end moraine, marking its greatest extent of the past 4000 years. Although the timing of several of the advances overlap with the age range of glacial expansion recognized elsewhere in Patagonia, some do not. Asynchronous behavior observed in the glacial record may arise from the type of evidence (e.g., lateral stratigraphy vs. end moraine) used to document glacial fluctuations or variations in climate or glacial response times. A significant difference between the Stoppani record and some other Patagonian records is that the former indicates general expansion of ice over the last 4000 years, whereas the latter indicate a net decrease in extent over that period.

Fishing Vessels of the Pacific Northwest: The Past 30 Years

1988 ◽  
Vol 25 (02) ◽  
pp. 105-117
Author(s):  
James A. Cole
Keyword(s):  
Pacific Northwest ◽  
Carrying Capacity ◽  
Principal Characteristics ◽  
Stability Problems ◽  
The Past ◽  
Fishing Vessels ◽  
Technological Advances ◽  
The Pacific ◽  
Different Types ◽  
Hull Design

This paper reviews the evolution of the design of fishing vessels of the Pacific Northwest over the past three decades. Since the vessels are designed to suit their particular fishery or fisheries, five different types are reviewed: gillnet boat, trollers, combination fishing vessels over a range of several sizes, tuna seiners, and stern trawlers. The paper shows how evolution has brought bigger vessels with increased carrying capacity, range, and endurance. Stability problems that have arisen with some of the types are also discussed. A section is devoted to each type summarizing its origins, its evolution, the fishery, fishing method, etc. This is followed by comparisons in hull design of the types reviewed with drawings of the vessels accompanied by their principal characteristics. The conclusion covers the technological advances in design and construction of the vessels and the increased sophistication of their machinery and equipment. An Appendix illustrates the operating areas and seasons of the Pacific Northwest fisheries and includes photographs of typical vessels of the region.

The Effects of Exogenous Bioregulators and Environment on Regular Cropping of Apple

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 554e-555
Author(s):  
Kathleen M. Williams
Keyword(s):  
Pacific Northwest ◽  
Cultural Practices ◽  
Negative Impact ◽  
Fruit Size ◽  
Physiological Status ◽  
Naphthalene Acetic Acid ◽  
Crop Load ◽  
The Past ◽  
The Pacific ◽  
Return Bloom

Use of exogenous bioregulators (“hormones”) to adjust crop load in apple remains challenging to both researchers and producers. These hormones are sensitive to the rate and timing of application, to the physiological status of the tree, the choice of orchard system, variety and rootstock, and a myriad of cultural practices and environmental factors. All classes of plant bioregulators have been used over the past 30 to 40 years as chemical thinning materials. Most of the standard postbloom thinning programs involve application of a synthetic auxin, such as naphthalene acetic acid (NAA) in combination with carbaryl, a commonly used insecticide. The mode of action of these two compounds is not clearly understood. Gibberellins generally have not been effective thinning materials because of the negative impact on return bloom. Ethylene-releasing compounds have been used successfully as postbloom thinning materials. And cytokinins, particularly synthetic sources such as 6-BA, have been shown to effectively thin fruit and to enhance fruit size on many commercial varieties. The rate and timing of 6-BA applications are particularly critical to obtain the desirable thinning and size responses. Overall, these bioregulators are sensitive to temperature. The use of bloom thinning compounds and their efficacy in the Pacific Northwest will be discussed in the context of return bloom.

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