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41.
J. Patrick Donnelly Jason D. Tack Kevin E. Doherty David E. Naugle Brady W. Allred Victoria J. Dreitz 《Strength and Conditioning Journal》2017,70(1):95-105
Recent and unprecedented scale of greater sage-grouse (Centrocercus urophasianus) conservation in the American West enables assessment of community-level benefits afforded to other sagebrush-obligate species. We use North American Breeding Bird Survey (BBS) count data and machine-learning to assess predictors influencing spatial distribution and abundance of three sagebrush-obligate songbirds (Brewer’s sparrow [Spizella breweri], sagebrush sparrow [Artemisiospiza nevadensis], and sage thrasher [Oreoscoptes montanus]). We quantified co-occurrence of songbird abundance with sage-grouse lek distributions using point pattern analyses and evaluated the concurrence of songbird abundance within sage-grouse habitat restoration and landscape protection. Sagebrush land-cover predictors were positively associated with the abundance of each songbird species in models that explained 16 ? 37% of variation in BBS route level counts. Individual songbird models identified an apparent 40% threshold in sagebrush land-cover, over which songbird abundances nearly doubled. Songbird abundances were positively associated with sage-grouse distributions (P < 0.01); range-wide, landscapes supporting > 50% of males on leks also harbored 13 ? 19% higher densities of songbirds compared with range-wide mean densities. Eighty-five percent of the conifer removal conducted through the Sage Grouse Initiative coincided with high to moderate Brewer’s sparrow abundance. Wyoming’s landscape protection (i.e., “core area”) strategy for sage-grouse encompasses half the high to moderate abundance sagebrush sparrow and sage thrasher populations. In the Great Basin half the high to moderate abundance sagebrush sparrow and sage thrasher populations coincide with sage-grouse Fire and Invasive Assessment Tool priorities, where conservation actions are being focused in an attempt to reduce the threat of wildfire and invasive plants. Our work illustrates spatially targeted actions being implemented ostensibly for sage-grouse largely overlap high abundance centers for three sagebrush obligate passerines and are likely providing significant conservation benefits for less well-known sagebrush songbirds and other sagebrush-associated wildlife. 相似文献
42.
Endoscopes are used for visualization and biopsy of gastrointestinal lesions, as well as therapeutic procedures, such as foreign body retrieval. In the past, they were primarily used in large institutional settings where specialized personnel could focus on their maintenance. Today, they are becoming increasingly common in general practice. The maintenance of gastrointestinal endoscopes in the veterinary setting involves many challenges, including safe handling, reprocessing, and storage. Meeting these challenges requires well-trained personnel and strict protocols. Reprocessing, which includes cleaning and disinfection, offers the greatest challenge. The complex structure of flexible endoscopes, particularly the long, narrow channels, makes them difficult to clean. Gastrointestinal endoscopes operate in a contaminated environment, exposing them to high levels of organic matter and bacteria. High-level disinfection is necessary for infection control, but liquid germicides available for endoscope disinfection can be toxic to medical personnel and patients. 相似文献
43.
Caleb P. Roberts Dirac Twidwell Jessica L. Burnett Victoria M. Donovan Carissa L. Wonkka Christine L. Bielski Ahjond S. Garmestani David G. Angeler Tarsha Eason Brady W. Allred Matthew O. Jones David E. Naugle Shana M. Sundstrom Craig R. Allen 《Strength and Conditioning Journal》2018,71(6):659-670
New concepts have emerged in theoretical ecology with the intent to quantify complexities in ecological change that are unaccounted for in state-and-transition models and to provide applied ecologists with statistical early warning metrics able to predict and prevent state transitions. With its rich history of furthering ecological theory and its robust and broad-scale monitoring frameworks, the rangeland discipline is poised to empirically assess these newly proposed ideas while also serving as early adopters of novel statistical metrics that provide advanced warning of a pending shift to an alternative ecological regime. We review multivariate early warning and regime shift detection metrics, identify situations where various metrics will be most useful for rangeland science, and then highlight known shortcomings. Our review of a suite of multivariate-based regime shift/early warning indicators provides a broad range of metrics applicable to a wide variety of data types or contexts, from situations where a great deal is known about the key system drivers and a regime shift is hypothesized a priori, to situations where the key drivers and the possibility of a regime shift are both unknown. These metrics can be used to answer ecological state-and-transition questions, inform policymakers, and provide quantitative decision-making tools for managers. 相似文献
44.
Jordan N Boody G Broussard W Glover JD Keeney D McCown BH McIsaac G Muller M Murray H Neal J Pansing C Turner RE Warner K Wyse D 《Science (New York, N.Y.)》2007,316(5831):1570-1571
A U.S. farm policy shift to joint production of commodities and ecological services will advance sustainable agriculture. 相似文献