scholarly journals Climate warming alters fuels across elevational gradients in Great Basin bristlecone pine-dominated sky island forests

2017 ◽  
Vol 392 ◽  
pp. 125-136 ◽  
Author(s):  
Curtis A. Gray ◽  
Michael J. Jenkins
Keyword(s):  
Great Basin ◽  
Climate Warming ◽  
Elevational Gradients ◽  
Bristlecone Pine ◽  
Sky Island

scholarly journals Post-Wildfire Regeneration in a Sky-Island Mixed- Conifer Ecosystem of the North American Great Basin

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 900
Author(s):  
Mackenzie Kilpatrick ◽  
Franco Biondi
Keyword(s):  
Great Basin ◽  
Basal Area ◽  
Climatic Conditions ◽  
Ecosystem Responses ◽  
Engelmann Spruce ◽  
The North ◽  
Bristlecone Pine ◽  
Snake Range ◽  
Disturbance Processes ◽  
Sky Island

Information on wildfire impacts and ecosystem responses is relatively sparse in the Great Basin of North America, where subalpine ecosystems are generally dominated by five-needle pines. We analyzed existing vegetation, with an emphasis on regeneration following the year 2000 Phillips Ranch Fire, at a sky-island site in the Snake Range of eastern Nevada. Our main objective was to compare bristlecone pine (Pinus longaeva; PILO) post-fire establishment and survival to that of the co-occurring dominant conifers limber pine (Pinus flexilis; PIFL) and Engelmann spruce (Picea engelmannii; PIEN) in connection with site characteristics. Field data were collected in 40 circular 0.1 ha plots (17.8 m radius) randomly located using GIS so that half of them were inside (“burned”) and half were outside (“unburned”) the 2000 fire boundary. While evidence of previous burns was also found, we focused on impacts from the Phillips Ranch Fire. Mean total basal area, including live and dead stems, was not significantly different between plots inside the burn and plots outside the fire perimeter, but the live basal area was significantly less in the former than in the latter. Wildfire impacts did not limit regeneration, and indeed bristlecone seedlings and saplings were more abundant in plots inside the 2000 fire perimeter than in those outside of it. PILO regeneration, especially saplings, was more abundant than PIFL and PCEN combined, indicating that PILO can competitively regenerate under modern climatic conditions. Surviving PILO regeneration in burned plots was also taller than that of PIFL. By contrast, PCEN was nearly absent in the plots that had been impacted by fire. Additional research should explicitly address how climatic changes and disturbance processes may interact in shaping future vegetation dynamics.

Holocene Climatic Variations Inferred from Treeline Fluctuations in the White Mountains, California

1973 ◽  
Vol 3 (4) ◽  
pp. 632-660 ◽  
Author(s):  
Valmore C. LaMarche
Keyword(s):  
Great Basin ◽  
Warm Season ◽  
White Mountains ◽  
North American Cordillera ◽  
Climatic Variations ◽  
The Past ◽  
The North ◽  
Pinus Longaeva ◽  
Bristlecone Pine ◽  
Dry Conditions

AbstractRemains of dead bristlecone pine (Pinus longaeva Bailey) are found at altitudes up to 150 m above present treeline in the White Mountains. Standing snags and remnants in two study areas were mapped and sampled for dating by tree-ring and radiocarbon methods. The oldest remnants represent trees established more than 7400 y.a. Experimental and empirical evidence indicates that the position of the treeline is closely related to warm-season temperatures, but that precipitation may also be important in at least one of the areas. The upper treeline was at high levels in both areas until after about 2200 B.C., indicating warm-season temperatures about 3.5°F higher than those of the past few hundred years. However, the record is incomplete, relative warmth may have been maintained until at least 1500 B.C. Cooler and wetter conditions are indicated for the period 1500 B.C.-500 B.C., followed by a period of cool but drier climate. A major treeline decline occurred between about A.D. 1100 and A.D. 1500, probably reflecting onset of cold and dry conditions. High reproduction rates and establishment of scattered seedlings at high altitudes within the past 100 yr represents an incipient treeline advance, which reflected a general climatic warming beginning in the mid-19th century that has lasted until recent decades in the western United States. This evidence for climatic variation is broadly consistent with the record of Neoglacial advances in the North American Cordillera, and supports Antevs' concept of a warm “altithermal age” in the Great Basin.

scholarly journals Defense traits in the long-lived Great Basin bristlecone pine and resistance to the native herbivore mountain pine beetle

2016 ◽  
Vol 213 (2) ◽  
pp. 611-624 ◽  
Author(s):  
Barbara J. Bentz ◽  
Sharon M. Hood ◽  
E. Matthew Hansen ◽  
James C. Vandygriff ◽  
Karen E. Mock
Keyword(s):  
Great Basin ◽  
Mountain Pine Beetle ◽  
Mountain Pine ◽  
Pine Beetle ◽  
Bristlecone Pine

scholarly journals Regeneration dynamics of Great Basin bristlecone pine in southern Nevada

2020 ◽  
Vol 50 (6) ◽  
pp. 589-594 ◽  
Author(s):  
Philip J. Burton ◽  
Jesy Simons ◽  
Steve Brittingham ◽  
Daniel B. Thompson ◽  
Darin W. Brooks ◽  
...  
Keyword(s):  
Great Basin ◽  
Seedling Emergence ◽  
Negative Relationship ◽  
The United States ◽  
Regeneration Dynamics ◽  
Heat Load Index ◽  
Southern Nevada ◽  
Adult Trees ◽  
Bristlecone Pine ◽  
Spring Mountains

Great Basin bristlecone pine (Pinus longaeva D.K. Bailey) is an important and long-lived tree species found at high elevations in the interior southwest of the United States, but little is known about its regeneration requirements and response to disturbance. We conducted extensive surveys of seedling regeneration and environmental attributes of regeneration sites in undisturbed forest dominated by this species in the Spring Mountains of southern Nevada. Additional surveys tallied new seedling densities and site attributes 4 years after a wildfire in the same area. Seedlings, saplings, and juvenile trees were less abundant than adult trees in the unburned forest, and soils had lower bulk density and greater depth, moisture, and soil organic matter under adult trees than in open areas. Seedling distributions in both unburned and burned forest showed a negative relationship to a heat load index governed by aspect. The density of new seedlings after the fire was negatively related to distance from unburned forest edges. Seedlings were found in clusters and were associated with adult trees (live or dead) in both unburned and burned stands. Seedling emergence from animal-dispersed caches was more frequent in burned habitats than in unburned habitats. These natural regeneration dynamics provide potential guidance for restoration efforts in this ecosystem.

scholarly journals Genetic Specificity in the White Pine-Blister Rust Pathosystem

2002 ◽  
Vol 92 (3) ◽  
pp. 278-280 ◽  
Author(s):  
Bohun B. Kinloch ◽  
Gayle E. Dupper
Keyword(s):  
North America ◽  
Great Basin ◽  
Single Gene ◽  
Low Frequency ◽  
White Pine Blister Rust ◽  
White Pine ◽  
Mendelian Segregation ◽  
Blister Rust ◽  
Sugar Pine ◽  
Bristlecone Pine

Four of eight white pine species native to western North America surveyed for resistance to white pine blister rust by artificial inoculation showed classical hypersensitive reactions (HR) at frequencies ranging from very low to moderate. Mendelian segregation, indicating a single dominant allele for resistance (Cr3), was observed in southwestern white pine (Pinus strobiformis), as it was previously in sugar pine (P. lambertiana, Cr1) and western white pine (P. monticola, Cr2). HR was present at a relatively high frequency (19%) in one of five bulk seed lot sources of limber pine (P. flexilis), and was also presumed to be conditioned by a single gene locus, by analogy with the other three species. HR was not found in whitebark pine (P. albcaulis), Mexican white pine (P. ayacahuite), foxtail pine (P. balfouriana), or Great Basin bristlecone pine (P. longaeva), but population and sample sizes in these species may have been below the level of detection of alleles in low frequency. When challenged by (haploid) inocula from specific locations known to harbor virulence to Cr1 or Cr2, genotypes carrying these alleles and Cr3 reacted differentially, such that inoculum virulent to Cr1 was avirulent to Cr2, and inoculum virulent to Cr2 was avirulent to Cr1. Neither of these two inocula was capable of neutralizing Cr3. Although blister rust traditionally is considered an exotic disease in North America, these results, typical of classic gene-for-gene interactions, suggest that genetic memory of similar encounters in past epochs has been retained in this pathosystem.

Recruitment patterns and growth of high-elevation pines in response to climatic variability (1883–2013), in the western Great Basin, USA

2015 ◽  
Vol 45 (10) ◽  
pp. 1299-1312 ◽  
Author(s):  
Constance I. Millar ◽  
Robert D. Westfall ◽  
Diane L. Delany ◽  
Alan L. Flint ◽  
Lorraine E. Flint
Keyword(s):  
Great Basin ◽  
Climatic Variability ◽  
High Elevation ◽  
Tree Line ◽  
Growth Responses ◽  
Lag Effects ◽  
Limber Pine ◽  
Pine Tree ◽  
Bristlecone Pine ◽  
Complex Relationships

Over the period 1883–2013, recruitment of subalpine limber pine (Pinus flexilis E. James) and Great Basin bristlecone pine (Pinus longaeva D.K. Bailey) above the upper tree line, below the lower tree line, and across middle-elevation forest borders occurred at localized sites across four mountain ranges in the western Great Basin. A synchronous pulse at all ecotones occurred between 1963 and 2000 (limber pine) and between 1955 and 1978 (bristlecone pine) when pines expanded 225 m beyond forest borders. Little recruitment occurred before this interval or in the 21st century. No obvious environmental factors distinguished recruitment locations from nonrecruitment locations. Where their ranges overlap, limber pine has leapfrogged above bristlecone pine by 300 m. Limber pine tree-ring chronologies, developed to compare radial-growth responses with recruitment, showed dominant pulses of increased growth during the same interval as recruitment. Significant climate correlations of growth and recruitment indicated lead and lag effects as much as 6 years and complex relationships with climate variables, corroborating the importance of cumulative climate effects relative to any single year. Water relations were the most important drivers of growth and recruitment and interacted with growing-season minimum and maximum temperatures. These results underscore the importance of studying ecotones at all margins when evaluating conifer response to climate change.

Sign in / Sign up

Export Citation Format

Share Document