scholarly journals Fire-scarred fossil tree from the Late Triassic shows a pre-fire drought signal

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Bruce A. Byers ◽  
Lucía DeSoto ◽  
Dan Chaney ◽  
Sidney R. Ash ◽  
Anya B. Byers ◽  
...  
Keyword(s):  
National Park ◽  
Wood Anatomy ◽  
Recovery Period ◽  
Late Triassic ◽  
Fire Scars ◽  
Ecological Processes ◽  
Fire Scar ◽  
Evolutionary Force ◽  
Ancient Forests

AbstractExploring features of wood anatomy associated with fire scars found on fossil tree trunks is likely to increase our knowledge of the environmental and ecological processes that occurred in ancient forests and of the role of fire as an evolutionary force. In Petrified Forest National Park, Arizona, where Late Triassic fossil trees are exposed, we found 13 examples of fossil logs with external features resembling modern fire scars. One specimen with the unambiguous external features of a fire scar was collected for analysis of its fossilized wood. A light-colored band composed of compressed and distorted tracheids was associated with the scarring event. Cell lumen diameter and cell wall thickness in the pre-scarring fossilized wood show a response similar to that described in modern trees experiencing drought conditions. Tracheids in the post-scarring wood are initially smaller, and then become larger than average following a recovery period, as is often observed in modern conifers following fire. The responses in external morphology and wood anatomy to drought and fire were similar to those of some modern trees and support the view that some forests may have experienced conditions favoring the evolution of fire-adapted traits for more than 200 million years.

A cross-dated fire history from coast redwood near Redwood National Park, California

1994 ◽  
Vol 24 (1) ◽  
pp. 21-31 ◽  
Author(s):  
Peter M. Brown ◽  
Thomas W. Swetnam
Keyword(s):  
Cross Sections ◽  
National Park ◽  
Fire History ◽  
Fire Frequency ◽  
Fire Scars ◽  
Coast Redwood ◽  
Complete Representation ◽  
Fire Scar ◽  
Redwood National Park ◽  
The Mean

Cross sections from coast redwood trees (Sequoiasempervirens (D.Don.)Endl.) in and near Redwood National Park were dendrochronologically cross-dated and used to develop a fire history from 1714 to 1985. A master chronology for the study area was first developed from old-growth trees and provided dating control for fire-scarred samples. Redwood offers a challenge for dendrochronology owing to partially absent rings (ring wedging) and uniform ring widths (complacency). Cross dating was successful in portions of 12 of 24 fire-scarred trees. Fire events were dated by noting the position of fire scars and other fire-associated ring structures (resin ducts, double latewood, growth releases, and ring separations) in the cross-dated ring series. Using only dates of fire scars, the mean fire interval (MFI) was 9.9 years from the first recorded fire in 1714 to the last in 1962. The MFI was 8.0 years for the best represented (greatest sample depth) presettlement period from 1714 to 1881. Using dates for all fire-associated ring features, the MFI from 1714 to 1962 was 7.0 years and from 1714 to 1881 was 6.0 years. Use of all fire-associated ring characteristics is argued to be a more complete representation of past fire frequency due to possible under-representation of fire-scar records from stump-top samples. Based upon scar positions within annual rings, fires occurred predominately late in the growing season or after growth ceased for the year. The mean fire intervals determined are shorter than those reported in all except one other fire history study from coast redwood and suggest that fire frequency in redwood may have been underestimated in many past studies.

Upper Triassic lithostratigraphy, depositional systems, and vertebrate paleontology across southern Utah

2017 ◽  
Vol 4 ◽  
pp. 99-180 ◽  
Author(s):  
Jeffrey W. Martz ◽  
James I. Kirkland ◽  
Andrew R.C. Milner ◽  
William G. Parker ◽  
Vincent L. Santucci
Keyword(s):  
National Park ◽  
Late Triassic ◽  
Zion National Park ◽  
Chinle Formation ◽  
Depositional Systems ◽  
Wingate Sandstone ◽  
San Rafael ◽  
San Rafael Swell ◽  
Petrified Forest ◽  
Moenave Formation

The Chinle Formation and the lower part of the overlying Wingate Sandstone and Moenave Formation were deposited in fluvial, lacustrine, paludal, and eolian environments during the Norian and Rhaetian stages of the Late Triassic (~230 to 201.3 Ma), during which time the climate shifted from subtropical to increasingly arid. In southern Utah, the Shinarump Member was largely confined to pre-Chinle paleovalleys and usually overprinted by mottled strata. From southeastern to southwestern Utah, the lower members of the Chinle Formation (Cameron Member and correlative Monitor Butte Member) thicken dramatically whereas the upper members of the Chinle Formation (the Moss Back, Petrified Forest, Owl Rock, and Church Rock Members) become erosionally truncated; south of Moab, the Kane Springs beds are laterally correlative with the Owl Rock Member and uppermost Petrified Forest Member. Prior to the erosional truncation of the upper members, the Chinle Formation was probably thickest in a southeast to northwest trend between Petrified Forest National Park and the Zion National Park, and thinned to the northeast due to the lower Chinle Formation lensing out against the flanks of the Ancestral Rocky Mountains, where the thickness of the Chinle is largely controlled by syndepositional salt tectonism. The Gartra and Stanaker Members of the Ankareh Formation are poorly understood Chinle Formation correlatives north of the San Rafael Swell. Osteichthyan fish, metoposaurid temnospondyls, phytosaurids, and crocodylomorphs are known throughout the Chinle Formation, although most remains are fragmentary. In the Cameron and Monitor Butte Members, metoposaurids are abundant and non-pseudopalatine phytosaurs are known, as is excellent material of the paracrocodylomorph Poposaurus; fragmentary specimens of the aetosaurs Calyptosuchus, Desmatosuchus, and indeterminate paratypothoracisins were probably also recovered from these beds. Osteichthyans, pseudopalatine phytosaurs, and the aetosaur Typothorax are especially abundant in the Kane Springs beds and Church Rock Member of Lisbon Valley, and Typothorax is also known from the Petrified Forest Member in Capitol Reef National Park. Procolophonids, doswelliids, and dinosaurs are known but extremely rare in the Chinle Formation of Utah. Body fossils and tracks of osteichthyans, therapsids, crocodylomorphs, and theropods are well known from the lowermost Wingate Sandstone and Moenave Formation, especially from the St. George Dinosaur Discovery Site at Johnson Farm.

THE ROLE OF SEA-LEVEL RISE AND STORMS IN FORMATION AND RESILIENCE OF FLORIDA BAY ISLANDS, EVERGLADES NATIONAL PARK

2019 ◽  
Author(s):  
G. Lynn Wingard ◽  
◽  
Miriam C. Jones ◽  
Sarah E. Bergstresser ◽  
Bethany L. Stackhouse ◽  
...  
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
National Park ◽  
Florida Bay ◽  
Everglades National Park ◽  
Bay Islands

Remembering the Battle of Pezi Sla (Greasy Grass—aka Little Bighorn) with the Lakota, Northern Cheyenne, and Arapaho Victory Riders: An Autoethnographic Photo Essay

2021 ◽  
pp. 153270862199112
Author(s):  
Elena Tajima Creef ◽  
Carl J. Petersen
Keyword(s):  
American History ◽  
National Park ◽  
National Park Service ◽  
Northern Cheyenne ◽  
Park Service ◽  
Photo Essay

If one travels to Little Bighorn Battlefield National Park in late June, one can witness at least three events that simultaneously take place each year commemorating what has been called “one of the great mythic and mysterious military battles of American history” (Frosch, 2010). The National Park Service rangers give “battle talks” on the hour to visiting tourists. Two miles away, the privately run U.S. Cavalry School also performs a scripted reenactment called “Custer’s Last Ride”—with riders who have been practicing all week to play the role of soldiers from the doomed regiment of Custer’s 7th Cavalry. On this same day, a traveling band of men, women, and youth from the Lakota, Northern Cheyenne, and Arapaho Nations who have journeyed by horseback and convoy from the Dakotas and Wyoming will reach Last Stand Hill to remember this “Victory Day” from 1876—one that historians have called the “last stand of the Indians” during the period of conflict known as the “Great Sioux War.” This photo essay offers an autoethnographic account of what some have dubbed the annual “Victory Ride” to Montana based upon my participation as a non-Native supporter of this Ride in 2017, 2018, and 2019.

scholarly journals Waterlogging-Stress-Responsive LncRNAs, Their Regulatory Relationships with MiRNAs and Target Genes in Cucumber (Cucumis sativus L.)

2021 ◽  
Vol 22 (15) ◽  
pp. 8197
Author(s):  
Kinga Kęska ◽  
Michał Wojciech Szcześniak ◽  
Adela Adamus ◽  
Małgorzata Czernicka
Keyword(s):  
Target Genes ◽  
Recovery Period ◽  
Sufficient Information ◽  
Low Oxygen ◽  
Waterlogging Tolerance ◽  
Cucumis Sativus L ◽  
Waterlogging Stress ◽  
Non Coding Rna

Low oxygen level is a phenomenon often occurring during the cucumber cultivation period. Genes involved in adaptations to stress can be regulated by non-coding RNA. The aim was the identification of long non-coding RNAs (lncRNAs) involved in the response to long-term waterlogging stress in two cucumber haploid lines, i.e., DH2 (waterlogging tolerant—WL-T) and DH4 (waterlogging sensitive—WL-S). Plants, at the juvenile stage, were waterlogged for 7 days (non-primed, 1xH), and after a 14-day recovery period, plants were stressed again for another 7 days (primed, 2xH). Roots were collected for high-throughput RNA sequencing. Implementation of the bioinformatic pipeline made it possible to determine specific lncRNAs for non-primed and primed plants of both accessions, highlighting differential responses to hypoxia stress. In total, 3738 lncRNA molecules were identified. The highest number (1476) of unique lncRNAs was determined for non-primed WL-S plants. Seventy-one lncRNAs were depicted as potentially being involved in acquiring tolerance to hypoxia in cucumber. Understanding the mechanism of gene regulation under long-term waterlogging by lncRNAs and their interactions with miRNAs provides sufficient information in terms of adaptation to the oxygen deprivation in cucumber. To the best of our knowledge, this is the first report concerning the role of lncRNAs in the regulation of long-term waterlogging tolerance by priming application in cucumber.

Microstructure of high-temperature (>73 °C) siliceous sinter deposited around hot springs and geysers, Yellowstone National Park: the role of biological and abiological processes in sedimentation

2003 ◽  
Vol 40 (11) ◽  
pp. 1611-1642 ◽  
Author(s):  
Donald R Lowe ◽  
Deena Braunstein
Keyword(s):  
High Temperature ◽  
Yellowstone National Park ◽  
National Park ◽  
Hot Springs ◽  
Strain Effect ◽  
Temperature Sinter ◽  
Architectural Features ◽  
Siliceous Sinter ◽  
High Temperature Sinter

Slightly alkaline hot springs and geysers in Yellowstone National Park exhibit distinctive assemblages of high-temperature (>73 °C) siliceous sinter reflecting local hydrodynamic conditions. The main depositional zones include subaqueous pool and channel bottoms and intermittently wetted subaerial splash, surge, and overflow areas. Subaqueous deposits include particulate siliceous sediment and dendritic and microbial silica framework. Silica framework forms thin, porous, microbe-rich films coating subaqueous surfaces. Spicules with intervening narrow crevices dominate in splash zones. Surge and overflow deposits include pool and channel rims, columns, and knobs. In thin section, subaerial sinter is composed of (i) dark brown, nearly opaque laminated sinter deposited on surfaces that evaporate to dryness; (ii) clear translucent silica deposited subaqueously through precipitation driven by supersaturation; (iii) heterogeneous silica representing silica-encrusted microbial filaments and detritus; and (iv) sinter debris. Brownish laminations form the framework of most sinter deposited in surge and overflow zones. Pits and cavities are common architectural features of subaerial sinter and show concave-upward pseudo-cross-laminations and micro-unconformities developed through migration. Marked birefringence of silica deposited on surfaces that evaporate to dryness is probably a strain effect. Repeated wetting and evaporation, often to dryness, and capillary effects control the deposition, morphology, and microstructure of most high-temperature sinter outside of the fully subaqueous zone. Microbial filaments are abundant on and within high-temperature sinter but do not provide the main controls on morphology or structuring except in biofilms developed on subaqueous surfaces. Millimetre-scale lamination cyclicity in much high-temperature sinter represents annual layering and regular seasonal fluctuations in silica sedimentation.

scholarly journals Pain therapy to reduce perioperative complications

2019 ◽  
Vol 4 (4) ◽  
pp. 158-166
Author(s):  
Stephan M. Freys ◽  
Esther Pogatzki-Zahn
Keyword(s):  
Postoperative Pain ◽  
Postoperative Complications ◽  
Adverse Events ◽  
Acute Pain ◽  
Surgical Procedure ◽  
Pain Therapy ◽  
Recovery Period ◽  
Acute Pain Therapy

AbstractThe incidence rates of adverse events secondary to any operation are a well-known problem in any surgical field. One outstanding example of such adverse events is postoperative pain. Thus, the incidence of acute postoperative pain following any surgical procedure and its treatment are central issues for every surgeon. In the times of Enhanced Recovery After Surgery (ERAS) programs, acute pain therapy became an increasingly well investigated and accepted aspect in almost all surgical subspecialties. However, if it comes to the reduction of postoperative complications, in the actual context of postoperative pain, surgeons tend to focus on the operative process rather than on the perioperative procedures. Undoubtedly, postoperative pain became an important factor with regard to the quality of surgical care: both, the extent and the quality of the surgical procedure and the extent and the quality of the analgesic technique are decisive issues for a successful pain management. There is growing evidence that supports the role of acute pain therapy in reducing postoperative morbidity, and it has been demonstrated that high pain scores postoperatively may contribute to a complicated postoperative course. This overview comprises the current knowledge on the role of acute pain therapy with regard to the occurrence of postoperative complications. Most of the knowledge is derived from studies that primarily focus on the type and quality of postoperative pain therapy in relation to specific surgical procedures and only secondary on complications. As far as existent, data that report on the recovery period after surgery, on the rehabilitation status, on perioperative morbidity, on the development of chronic pain after surgery, and on possible solutions of the latter problem with the institution of transitional pain services will be presented.

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