184 research outputs found
Effects of burning season and frequency on the vegetative character and insect abundance of sand shinnery oak range in western Oklahoma
Water Quality in the Agronomic Context: Flood Irrigation Impacts on Summer In-Stream Temperature Extremes in the Interior Pacific Northwest (USA)
Investigating the Correlation Between LPR & Obesity
Objectives: To determine whether Drug-Induced Sleep Endoscopy (DISE) findings of Laryngopharyngeal Reflux (LPR) correlate with obesity, gender, Epworth Sleepiness scale, and OSA severity.
Study design: Single center retrospective cohort study.
Methods: Patients greater than 18 years of age who underwent DISE by one surgeon at a tertiary care center from July 2016 to July 2022 were included. DISE findings, patient characteristics, demographics, polysomnogram(s), and Epworth Sleepiness Scale(s) were extracted. Fisher’s exact test was used to compare categorical variables, and independent sample t-test was used to compare continuous variables. All statistical analyses were performed using IBM SPSS Statistics 28.
Results: The study included 178 patients (60.87 years ± 11.54; 31.24 BMI ± 6.21). 38 patients had LPR, and 103 patients had a BMI\u3e30. LPR+ patients BMI was 33.11 ± 5.60, and LPR- patients BMI was 30.74 ± 6.28. There was a statistically significant relationship between obesity and LPR (p = 0.005). Additionally, obesity mild-moderately affected patients having LPR (d = .404). There was no statistically significant difference between LPR+ patients and ESS, AHI, and gender (p = .395, .174, & .302 respectively).
Conclusion: DISE aids in the diagnosis and evaluation of Obstructive Sleep Apnea (OSA) by simulating natural sleep. Using this highly precise diagnostic procedure, our study shows a relationship between findings of LPR in obese patients with obesity playing a small-medium role. There was no difference between LPR and ESS, AHI, and gender
To burn or not to burn: Comparing reintroducing fire with cutting an encroaching conifer for conservation of an imperiled shrub‐steppe
Woody vegetation has increased on rangelands worldwide for the past 100– 200 years, often because of reduced fire frequency. However, there is a general aversion to reintroducing fire, and therefore, fire surrogates are often used in its place to reverse woody plant encroachment. Determining the conservation effectiveness of reintroducing fire compared with fire surrogates over different time scales is needed to improve conservation efforts. We evaluated the conservation effectiveness of reintroducing fire with a fire surrogate (cutting) applied over the last ~30 years to control juniper (Juniperus occidentalis Hook.) encroachment on 77 sagebrush‐steppe sites. Critical to conservation of this imperiled ecosystem is to limit juniper, not encourage exotic annual grasses, and promote sagebrush dominance of the overstory. Reintroducing fire was more effective than cutting at reducing juniper abundance and extending the period of time that juniper was not dominating the plant community. Sagebrush was reduced more with burning than cutting. Sagebrush, however, was predicted to be a substantial component of the overstory longer in burned than cut areas because of more effective juniper control. Variation in exotic annual grass cover was explained by environmental variables and perennial grass abundance, but not treatment, with annual grasses being problematic on hotter and drier sites with less perennial grass. This suggests that ecological memory varies along an environmental gradient. Reintroducing fire was more effective than cutting at conserving sagebrush‐steppe encroached by juniper over extended time frames; however, cutting was more effective for short‐term conservation. This suggests fire and fire surrogates both have critical roles in conservation of imperiled ecosystems
The Sage-Grouse Habitat Mortgage: Effective Conifer Management in Space and Time
AbstractManagement of conservation-reliant species can be complicated by the need to manage ecosystem processes that operate at extended temporal horizons. One such process is the role of fire in regulating abundance of expanding conifers that disrupt sage-grouse habitat in the northern Great Basin of the United States. Removing conifers by cutting has a beneficial effect on sage-grouse habitat. However, effects may last only a few decades because conifer seedlings are not controlled and the seed bank is fully stocked. Fire treatment may be preferred because conifer control lasts longer than for mechanical treatments. The amount of conservation needed to control conifers at large temporal and spatial scales can be quantified by multiplying land area by the time needed for conifer abundance to progress to critical thresholds (i.e., “conservation volume”). The contribution of different treatments in arresting conifer succession can be calculated by dividing conservation volume by the duration of treatment effect. We estimate that fire has approximately twice the treatment life of cutting at time horizons approaching 100 yr, but, has high up-front conservation costs due to temporary loss of sagebrush. Cutting has less up-front conservation costs because sagebrush is unaffected, but it is more expensive over longer management time horizons because of decreased durability. Managing conifers within sage-grouse habitat is difficult because of the necessity to maintain the majority of the landscape in sagebrush habitat and because the threshold for negative conifer effects occurs fairly early in the successional process. The time needed for recovery of sagebrush creates limits to fire use in managing sage-grouse habitat. Utilizing a combination of fire and cutting treatments is most financially and ecologically sustainable over long time horizons involved in managing conifer-prone sage-grouse habitat
Saving the sagebrush sea: An ecosystem conservation plan for big sagebrush plant communities
Vegetation change and anthropogenic development are altering ecosystems and decreasing biodiversity. Successful management of ecosystems threatened by multiple stressors requires development of ecosystem conservation plans rather than single species plans. We selected the big sagebrush (Artemisia tridentata Nutt.) ecosystem to demonstrate this approach. The area occupied by the sagebrush ecosystem is declining and becoming increasingly fragmented at an alarming rate because of conifer encroachment, exotic annual grass invasion, and anthropogenic development. This is causing rangewide declines and localized extirpations of sagebrush associated fauna and flora. To develop an ecosystem conservation plan, a synthesis of existing knowledge is needed to prioritize and direct management and research. Based on the synthesis, we concluded that efforts to restore higher elevation conifer-encroached, sagebrush communities were frequently successful, while restoration of exotic annual grass-invaded, lower elevation, sagebrush communities often failed. Overcoming exotic annual grass invasion is challenging and needs additional research to improve the probability of restoration and identify areas where success would be more probable. Management of fire regimes will be paramount to conserving sagebrush communities, as infrequent fires facilitate conifer encroachment and too frequent fires promote exotic annual grasses. Anthropogenic development needs to be mitigated and reduced to protect sagebrush communities and this probably includes more conservation easements and other incentives to landowners to not develop their properties. Threats to the sustainability of sagebrush ecosystem are daunting, but a coordinated ecosystem conservation plan that focuses on applying successful practices and research to overcome limitations to conservation is most likely to yield success
Restoring North America’s Sagebrush Steppe Ecosystem Using Seed Enhancement Technologies
Rangelands occupy over a third of global land area, and in many cases are in less than optimum condition as a result of past land use, catastrophic wildfire and other disturbance, invasive species, or climate change. Often the only means of restoring these lands involves seeding desirable species, yet there are few cost effective seeding technologies, especially for the more arid rangeland types. The inability to consistently establish desired plants from seed may indicate that the seeding technologies being used are not successful in addressing the primary sources of mortality in the progression from seed to established plant. Seed enhancement technologies allow for the physical manipulation and application of materials to the seed that can enhance germination, emergence, and/or early seedling growth. In this article we examine some of the major limiting factors impairing seedling establishment in North America’s native sagebrush steppe ecosystem, and demonstrate how seed enhancement technologies can be employed to overcome these restoration barriers. We discuss specific technologies for: (1) increasing soil water availability; (2) enhancing seedling emergence in crusting soil; (3) controlling the timing of seed germination; (4) improving plantability and emergence of small seeded species; (5) enhancing seed coverage of broadcasted seeds; and (6) improving selectivity of pre-emergent herbicide. Concepts and technologies in this paper for restoring the sagebrush steppe ecosystem may apply generally to semi-arid and arid rangelands around the globe
Upland Bare Ground and Riparian Vegetative Cover Under Strategic Grazing Management, Continuous Stocking, and Multiyear Rest in New Mexico Mid-grass Prairie
On the Ground
• We compared land cover attributes on rangeland pastures with strategically managed ranches (SGM), continuously stocked (CS), and rested pastures.
• SGM pastures had less upland bare ground and more riparian vegetative cover than adjoining CS pastures, and SGM pastures had bare ground cover comparable to pastures rested from grazing for three or more years.
• Differences in riparian cover between management types were greatest in years of near-average precipitation and lower in years of high precipitation or drought.
• Remote sensing technologyprovided a means of quantifying range condition and comparing management effectiveness on large landscapes in a constantly changing environment
Upland Bare Ground and Riparian Vegetative Cover Under Strategic Grazing Management, Continuous Stocking, and Multiyear Rest in New Mexico Mid-grass Prairie
On the Ground
• We compared land cover attributes on rangeland pastures with strategically managed ranches (SGM), continuously stocked (CS), and rested pastures.
• SGM pastures had less upland bare ground and more riparian vegetative cover than adjoining CS pastures, and SGM pastures had bare ground cover comparable to pastures rested from grazing for three or more years.
• Differences in riparian cover between management types were greatest in years of near-average precipitation and lower in years of high precipitation or drought.
• Remote sensing technologyprovided a means of quantifying range condition and comparing management effectiveness on large landscapes in a constantly changing environment
- …