scholarly journals Conifer Root Proliferation after 20 Years of Soil Compaction

2016 ◽  
Vol 63 (2) ◽  
pp. 147-150 ◽  
Author(s):  
Matt D. Busse ◽  
Gary O. Fiddler ◽  
Carol J. Shestak
Keyword(s):  
Sierra Nevada ◽  
Soil Compaction ◽  
Lateral Root ◽  
The United States ◽  
Forest Harvesting ◽  
Tree Roots ◽  
Root Numbers ◽  
Rooting Patterns ◽  
Study Sites ◽  
Root Movement

Soil compaction is known to limit plant growth by reducing soil macroporosity and restricting gas, water, and root movement. Recent evidence from study sites across the United States and Canada, however, suggests that tree growth is not universally affected by soil compaction from forest harvesting practices. Our observational study examined rooting patterns in mixed conifer plantations in the central Sierra Nevada of California to determine whether tree roots use continuous pathways or channels to overcome the physical restrictions of compacted soil. Replicate plots were established 20–25 years earlier to compare compacted and uncompacted treatments after clearcut harvesting. Fine and lateral root counts were taken at multiple depths in soil trenches. Rooting was extensive in compacted plots despite consistently high soil strength values (~3 MPa). No differences in rooting patterns or in fine or lateral root numbers were detected between compaction treatments. The results indicated long-term tolerance by conifer roots to soil compaction without clear use of preferential channels or uncompacted zones.

A modern perspective on Meinecke’s 1929 assessment of tourist impacts on redwoods

2021 ◽  
pp. 030913332110299
Author(s):  
Ross H Martin ◽  
Joshua B Hodge ◽  
Clayton J Whitesides
Keyword(s):  
Climate Change ◽  
Soil Compaction ◽  
Management Practices ◽  
Negative Impact ◽  
Tree Roots ◽  
Tourism Management ◽  
Modern Perspective ◽  
Impacts Of Climate Change

E.P. Meinecke, a noted plant pathologist and staunch supporter of conservation, authored an influential article about the impacts of tourism on redwood trees. In the Effect of Excessive Tourist Travel on the California Redwood Parks, published in 1929, Meinecke found that soil compaction by tourists had a negative impact on tree roots and his recommendations for amelioration were both logical and laced with philosophical ideals. We revisit that report with a modern perspective by reviewing his findings and suggestions, and by comparing his ideas with modern research and tourism management practices. One of Meinecke’s greatest concerns was the advent of the automobile and its ability to bring more people to redwood groves. We take that concern to the next logical step and discuss potential impacts of climate change on redwood trees.

scholarly journals Elegy Written in a Country Schoolhouse

2013 ◽  
Vol 3 (1) ◽  
pp. 41-49 ◽  
Author(s):  
Howard Hendrix
Keyword(s):  
United States ◽  
Private Sector ◽  
Sierra Nevada ◽  
The United States ◽  
Political Factors ◽  
Fresno County ◽  
The Public ◽  
School Year ◽  
Sierra Nevada Foothills ◽  
The Relationship

Article examines the economic, environmental, social, and political factors involved in the closing of Auberry Elementary School in the Sierra Nevada foothills of Fresno County after the 2010–2011 school year. The closing of the school serves as a window onto the shifting landscape of the relationship between the private sector and the public good not only in Auberry but throughout California and the United States.

scholarly journals Improving WSR-88D Radar QPE for Orographic Precipitation Using Profiler Observations

2014 ◽  
Vol 15 (3) ◽  
pp. 1135-1151 ◽  
Author(s):  
Youcun Qi ◽  
Jian Zhang ◽  
Brian Kaney ◽  
Carrie Langston ◽  
Kenneth Howard
Keyword(s):  
Sierra Nevada ◽  
West Coast ◽  
Heavy Rain ◽  
Moisture Flux ◽  
Heavy Precipitation ◽  
The United States ◽  
The West ◽  
Radar Beam ◽  
Orographic Enhancement ◽  
Coast Region

Abstract Quantitative precipitation estimation (QPE) in the West Coast region of the United States has been a big challenge for Weather Surveillance Radar-1988 Doppler (WSR-88D) because of severe blockages caused by the complex terrain. The majority of the heavy precipitation in the West Coast region is associated with strong moisture flux from the Pacific that interacts with the coastal mountains. Such orographic enhancement of precipitation occurs at low levels and cannot be observed well by WSR-88D because of severe blockages. Specifically, the radar beam either samples too high above the ground or misses the orographic enhancement at lower levels, or the beam broadens with range and cannot adequately resolve vertical variations of the reflectivity structure. The current study developed an algorithm that uses S-band Precipitation Profiler (S-PROF) radar observations in northern California to improve WSR-88D QPEs in the area. The profiler data are used to calculate two sets of reference vertical profiles of reflectivity (RVPRs), one for the coastal mountains and another for the Sierra Nevada. The RVPRs are then used to correct the WSR-88D QPEs in the corresponding areas. The S-PROF–based VPR correction methodology (S-PROF-VPR) has taken into account orographic processes and radar beam broadenings with range. It is tested using three heavy rain events and is found to provide significant improvements over the operational radar QPE.

scholarly journals Insight into the Productivity, Cost and Soil Impacts of Cable-assisted Harvester-forwarder Thinning in Western Oregon

2019 ◽  
Vol 66 (1) ◽  
pp. 82-96 ◽  
Author(s):  
Preston Q Green ◽  
Woodam Chung ◽  
Ben Leshchinsky ◽  
Francisca Belart ◽  
John Sessions ◽  
...  
Keyword(s):  
Pacific Northwest ◽  
Soil Compaction ◽  
The United States ◽  
Soil Conditions ◽  
Productivity Cost ◽  
System Productivity ◽  
Machine Productivity ◽  
Before And After ◽  
Harvesting Systems ◽  
Soil Measurements

Abstract Cable-assisted (or tethered) mechanized harvesting has recently been introduced to the Pacific Northwest of the United States, and is rapidly being adopted by the forest industry. However, potential environmental impacts, productivity and cost of the new harvesting systems have not been well-assessed. This study aims to examine the effects of cable assistance on soil compaction, system productivity and cost through a field-based experiment. A harvester-forwarder system was used to thin a harvest unit on dry soils in western Oregon, with and without cable-assistance. We conducted a detailed time study during operations and collected soil measurements before and after machine passes. Machine productivity ranged from 28.75 to 92.36 m3 per scheduled machine hour, with resulting unit costs for untethered and tethered systems ranging from $13.19 to $18.13/m3. Our results showed reduced soil impacts in both extent and degree of soil compaction when cable assistance was employed. The reduced extent of soil impacts is attributed to a reduction in track wander owing to the operative tensions of the tether cable, and the smaller increase in soil density appears to be attributed to combined effects of initially denser soil conditions and reduced shear displacement as a result of cable-assistance.

The Neat-HER Virtual Registry: A novel registry following HER2+ ESBC patients receiving neratinib in the extended adjuvant setting.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e12035-e12035 ◽  
Author(s):  
Debu Tripathy ◽  
Gregory A. Vidal ◽  
Deepa Lalla ◽  
Richard Bryce ◽  
Gillian Hanson ◽  
...  
Keyword(s):  
Real World ◽  
Medical Records ◽  
Clinical History ◽  
The United States ◽  
World Population ◽  
Duration Of Treatment ◽  
Cancer History ◽  
Data Points ◽  
Research Questions ◽  
Study Sites

e12035 Background: While data from traditional registries are limited to patients (pts) treated at study sites, virtual registries can enroll a more diverse real-world population. Neat-HER is a US-based, non-interventional pilot virtual registry through PicnicHealth that will enroll 100 pts with HER2+ BC receiving neratinib as extended adjuvant therapy. Methods: Neat-HER will evaluate the feasibility of enrolling pts & answering research questions using this novel methodology. Eligibility includes receipt of neratinib, signed informed consent for medical record retrieval/data abstraction & > 18 years age at study consent. Pts who fail to complete enrollment procedures, are participating in a clinical trial, have metastatic disease, or who lack adequate medical records will be excluded. For each pt discontinuing neratinib within 60 days of starting treatment, an additional pt will be recruited, but all pts will be included in the analysis. Pts are recruited through multiple mechanisms incl. private social media groups, treating clinicians & pts enrolled in the Puma texting program. PicnicHealth will collect & structure medical records from medical practices in the United States for ~7 years prior to enrolment up to 1 year after enrolment. Research questions focus on descriptive pt characteristics & demographics, breast cancer history [(neo)adjuvant treatment/outcomes], use of diarrhea prophylaxis, incidence of diarrhea & duration of neratinib. Results: Enrollment began in 12/2018 with target completion in 4/2019. As of 2/2019, 42 pts have initiated enrolment. Of these, 19 pts completed enrolment & 69,750 data points have been extracted from medical records. Descriptive statistics will be used to characterize the pt cohort. Duration of treatment, receipt & type of prophylaxis, incidence of diarrhea, treatment discontinuation & reasons for discontinuation will be summarized for all pts. Conclusions: A virtual registry allows assessment of medication use & outcomes in a diverse population in a rapid timeframe. Neat-HER will provide comprehensive information on clinical history & treatment patterns in a real-world cohort of pts receiving extended adjuvant neratinib.

scholarly journals The importance of private lands for ocelot Leopardus pardalis conservation in the United States

Oryx ◽  
2006 ◽  
Vol 40 (1) ◽  
pp. 90-94 ◽  
Author(s):  
Aaron M. Haines ◽  
Jan E Janecka ◽  
Michael E. Tewes ◽  
Lon I. Grassman Jr ◽  
Patricia Morton
Keyword(s):  
Recovery Process ◽  
The United States ◽  
Camera Traps ◽  
Private Landowners ◽  
Private Lands ◽  
Leopardus Pardalis ◽  
Abundance Estimate ◽  
Conservation Implications ◽  
The Usa ◽  
Study Sites

The distribution of ocelots Leopardus pardalis in the USA is limited to southern Texas. Identification and monitoring of ocelot populations enables biologists to assess population health and status. Use of camera traps has been successfully used to monitor numerous populations of wild felids, including the ocelot. Our objectives were to identify ocelot presence within southern Texas and estimate ocelot population size and density. We used camera traps to survey for ocelots on four study sites in southern Texas. We recorded ocelot presence on one study site with an abundance estimate of three individuals and a density estimate of 0.30±SE 0.03 ocelots km−2. The conservation implications of this study suggest concentrating conservation efforts in and around the study site (Yturria Ranch) found to have ocelots. In addition, this study emphasizes the importance of including private landowners in the ocelot recovery process.

scholarly journals Simulated Changes in Northwest U.S. Climate in Response to Amazon Deforestation*

2013 ◽  
Vol 26 (22) ◽  
pp. 9115-9136 ◽  
Author(s):  
David Medvigy ◽  
Robert L. Walko ◽  
Martin J. Otte ◽  
Roni Avissar
Keyword(s):  
United States ◽  
Sierra Nevada ◽  
Numerical Models ◽  
Regional Climate ◽  
Regional Climate Change ◽  
The United States ◽  
Far Field ◽  
Adequate Model ◽  
Thermal Anomalies ◽  
The Andes

Abstract Numerical models have long predicted that the deforestation of the Amazon would lead to large regional changes in precipitation and temperature, but the extratropical effects of deforestation have been a matter of controversy. This paper investigates the simulated impacts of deforestation on the northwest United States December–February climate. Integrations are carried out using the Ocean–Land–Atmosphere Model (OLAM), here run as a variable-resolution atmospheric GCM, configured with three alternative horizontal grid meshes: 1) 25-km characteristic length scale (CLS) over the United States, 50-km CLS over the Andes and Amazon, and 200-km CLS in the far-field; 2) 50-km CLS over the United States, 50-km CLS over the Andes and Amazon, and 200-km CLS in the far-field; and 3) 200-km CLS globally. In the high-resolution simulations, deforestation causes a redistribution of precipitation within the Amazon, accompanied by vorticity and thermal anomalies. These anomalies set up Rossby waves that propagate into the extratropics and impact western North America. Ultimately, Amazon deforestation results in 10%–20% precipitation reductions for the coastal northwest United States and the Sierra Nevada. Snowpack in the Sierra Nevada experiences declines of up to 50%. However, in the coarse-resolution simulations, this mechanism is not resolved and precipitation is not reduced in the northwest United States. These results highlight the need for adequate model resolution in modeling the impacts of Amazon deforestation. It is concluded that the deforestation of the Amazon can act as a driver of regional climate change in the extratropics, including areas of the western United States that are agriculturally important.

scholarly journals Influence of snow water equivalent on droughts and their prediction in the USA

2018 ◽  
Author(s):  
Daniel Abel ◽  
Felix Pollinger ◽  
Heiko Paeth
Keyword(s):  
Sierra Nevada ◽  
Large Scale ◽  
Snow Water Equivalent ◽  
Southern Oscillation ◽  
Original Data ◽  
The United States ◽  
Early Summer ◽  
Drought Severity ◽  
Southern Us ◽  
Snow Water

Abstract. Droughts can result in enormous impacts for environment, societies, and economy. In arid or semiarid regions with bordering high mountains, snow is the major source of water supply due to its role as natural water storage. The goal of this study is to examine the influence of snow water equivalent (SWE) on droughts in the United States and find large-scale climatic predictors for SWE and drought. For this, a Maximum Covariance Analysis (MCA), also known as Singular Value Decomposition, is performed with snow data from the ERA–Interim reanalysis and the self-calibrating Palmer Drought Severity Index (sc–PDSI) as drought index. Furthermore, the relationship of resulting principal components and original data with atmospheric patterns is investigated. The leading mode shows the spatial connection between SWE and drought via downstream water/moisture transport. Especially the Rocky Mountains in Colorado (CR) play a key role for the central and western South, but the Sierra Nevada and even the Appalachian Mountains are relevant, too. The temperature and precipitation based sc–PDSI is able to capture this link because increased soil moisture results in higher evapotranspiration with lower sensible heat and vice versa. A time shifted MCA indicates a prediction skill for drought conditions in spring and early summer for the downstream regions of CR on the basis of SWE in March. Furthermore, the phase of the El Niño–Southern Oscillation is a good predictor for drought in the southern US and SWE around Colorado. The influence of the North Atlantic Oscillation and Pacific North American Pattern is not that clear.

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