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Modeling visitor use on high elevation mountain trails: An example from Longs Peak in Rocky Mountain National Park, USA

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Journal of Mountain Science 2019年第12期16卷 2882-2893页

作者： David PETTEBONE Ashley D'ANTONIO Abigail SISNEROS-KIDD Christopher MONZ National Park Service Natural Resources Stewardship and ScienceEnvironmental Quality DivisionSocial Science Program80525 Fort CollinsColoradoUSA Oregon state University Department of Forest Ecosystems and Society97331 CorvallisOregonUSA utah state University Quinney College of Natural Resources84322 LoganUtahUSA Current Affiliation:University of Wyoming Haub School of Environment and Natural Resources82072 LaramieWyomingUSA

Increasing use on mountain summits has both social and ecological *** numbers of visitors climbing mountain summits can be a safety issue,particularly in areas where terrain or elevation leads to queueing that may cause time *** visitor use levels at site specific locations en route to summits is needed to understand the potential benefits and impacts of visitor use in these ***,it can be difficult to obtain reliable and robust data to estimate use and develop statistical relationships because of the remote and harsh climates on mountain summits,as well as the financial and personnel requirements involved to collect the data in remote *** 2015,data were collected on the higher stretches of the Keyhole Route on Longs Peak in Rocky Mountain National Park,USA(RMNP)to better understand use levels near the summit and to explore potential statistical relationships to trailhead use data that are relatively easy to *** statistical relationships from robust regression analyses were found between trailhead use counts and daily and hourly use totals on the"Homestretch"which is a final section of the Keyhole ***,a strong statistical relationship was found between total daily use and maximum hourly use on the *** results suggest that trailhead counts are an accurate and reliable means from which to estimate use levels on upper portions of the Keyhole ***,this research demonstrates the usefulness of an approach using proxy variables to estimate visitor use along remote peaks where data collection can be *** types of data can elucidate various options and decisions for park management teams who are charged with deciding if and how to manage high use areas.

关键词： Visitor use Mountain summits National parks Use estimation Recreation use Proxy variables

Vegetation Geo-climatic Zonation in the Rocky Mountains, Northern utah, USA

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Journal of Mountain Science 2014年第3期11卷 656-673页

作者： Antonin KUSBACH Helga VAN MIEGROET Janis L.BOETTINGER James N.LONG Department of Wildland Resources and Ecology Center Utah State University utah state University Department of Forest Botany Dendrology and Geobiocoenology Mendel University in Brno

We developed a vegetation geo-climatic zonation incorporating the zonal concept, gradient and discriminant analysis in Wasatch Range, northern utah, USA. Mountainous forest ecosystems were sampled and described by vegetation, physiographic features and soil properties. The Snowpack Telemetry and National Weather Service Cooperative Observer Program weather station networks were used to approximate the climate of sample plots. We analysed vegetation and environmental data using clustering, ordination, classification, and ANOVA techniques to reveal environmental gradients affecting a broad vegetation pattern and discriminate these gradients. The specific objective was to assess and classify the response of the complex vegetation to those environmental factors operating at a coarse-scale climatic level. Ordination revealed the dominant role of regional, altitude-based climate in the area. Based on vegetation physiognomy, represented by five tree species, climatic data and taxonomic classification of zonal soils, we identified two vegetation geo-climatic zones:(1) a montane zone, with Rocky Mountain juniper and Douglas-fir; and(2) a subalpine zone, with Engelmann spruce and subalpine fir as climatic climax species. Aspen was excluded from the zonation due to its great ecological amplitude. We found significant differences between the zones in regional climate and landformgeomorphology/soils. Regional climate was represented by elevation, precipitation, and air and soil temperatures; and geomorphology by soil types. This coarse-scale vegetation geo-climatic zonation provides a framework for a comprehensive ecosystem survey, which is missing in the central Rocky Mountains of the United states. The vegetation-geoclimatic zonation represents a conceptual improvement on earlier classifications. This framework explicitly accounts for the influence of the physical environment on the distribution of vegetation within a complex landscape typical of the central Rocky Mountains an

关键词： Ecological classification Ecosystemsurvey Land classification Zonal concept Vegetation zone Vegetation geo-dimatic zone Climate change

Viability and hatchability of brine shrimp Artemia franciscana cysts after passing through the digestive system of eared grebes Podiceps nigricollis

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Journal of Oceanology and Limnology 2023年第4期41卷 1300-1306页

作者： Michael R.CONOVER Mark E.BELL Leah M.DELAHOUSSAYE Department of Wildland Resources and Ecology Center LoganUT 84322-5230USA

Brine shrimp Artemia franciscana provide food for many migrating and staging birds that spend summer and fall on Great Salt Lake,utah,*** produce live young and cysts(hard-walled eggs);these cysts are commercially harvested on Great Salt Lake and support a large industry in *** is unclear the impact that millions of hungry birds have on the Artemia population in the *** help assess that,this study evaluated cyst viability(percentage of cysts that contain an embryo)and hatchability(percent of cysts that hatch)from cysts that had passed through the digestive tract of eared grebes Podiceps nigricollis and cysts obtained directly from Great Salt Lake at the same site where each grebe was *** was significantly higher for cysts collected from the water column(19%)than from the stomach(0.3%)or intestines(3%)of eared *** also was significantly different for cysts collected from the water column(29%),stomach(0.7%),and intestines(5%).These results indicate that eared grebes nutritionally benefit from eating cysts and that they may be an important food source for grebes in late fall after the adult population of Artemia dies off due to the water becoming too ***,enough cysts survive their passage through the digestive system that grebes can vector hatchable cysts to other waterbodies.

关键词： Artemia dispersal eared grebes hatchability invasive species Great Salt Lake salty lakes viability

Electromagnetic induction mapping at varied soil moisture reveals field-scale soil textural patterns and gravel lenses

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Frontiers of agricultural Science and Engineering 2017年第2期4卷 135-145页

作者： Hiruy ABDU David A.ROBINSON Janis BOETTINGER Scott B.JONES Biological and Irrigation Engineering Department Utah State University Centre for Ecology & Hydrology Environment Centre Wales Plants Soils and Climate Department Utah State University

Knowledge of the spatial distribution of soil textural properties is important for determining soil moisture storage and soil hydraulic transport *** field heterogeneity without exhaustive sampling and costly sample analysis is difficult. Our objective was to employ electromagnetic induction(EMI) mapping in low apparent electrical conductivity(EC_a) soils at varying soil water contents to capture time invariant properties such as soil texture. Georeferenced EC_ameasurements were taken using a ground conductivity meter on six different days where volumetric water content(θ_v) varied from 0.11 to 0.23. The 50 m × 50 m field included a subsurface gravelly patch in an otherwise homogeneous silt-loam alluvial *** block kriging predicted EC_aat unsampled areas to produce 1-m resolution maps. Temporal stability analysis was used to divide the field into three distinct EC_a regions. Subsequent ground-truthing confirmed the lowest conductivity region correlated with coarse textured soil parent materials associated with a former high-energy alluvial depositional area. Combining maps using temporal stability analysis gives the clearest image of the textural difference. These maps could be informative for modeling,experimental design, sensor placement and targeted zone management strategies in soil science, ecology, hydrology,and agricultural applications.

关键词： soil electrical conductivity soil texture mapping temporal stability analysis

Influence of harvest date on seed yield and quality in forage kochia

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Frontiers of agricultural Science and Engineering 2018年第1期5卷 71-79页

作者： Cody F.CREECH Blair L.WALDRON Corey V.RANSOM Dale R.ZOBELL Joseph Earl CREECH Department of Plants Soils and Climate Utah State University USDA-ARS Forage and Range Research Laboratory Department of Animal Dairy and Veterinary Sciences Utah State University

Forage kochia(Bassia prostrata) is used for rangeland reclamation and livestock and wildlife forage,but limited research has been conducted on its seed production. Therefore, this research evaluated the effect of harvest date on seed weight, germination, and seed yield of forage kochia subspecies virescens and grisea. Seed was harvested from individual plants for 3 years during October, November, and December. October harvest had the lightest 100-seed weights, with the November harvest slightly heavier than December, for most *** Snowstorm and breeding line Sahsel, both subsp. grisea, had the greatest 100-seed weights in November, 155 and 143 mg, respectively, whereas, ***(subsp. virescens), the standard for forage kochia, ranked among the least for 100-seed weight. For most accessions, germination was lowest from the October harvest(11%–43%), with greater germination with November and December harvested seeds(43%–64%).Viable seed yields were greatest in November with the exception of two accessions, which peaked in October,indicating earlier maturity. Results indicate that forage kochia usually reaches optimum seed maturity by early November, after plants are exposed to freezing temperatures; however, earlier maturing accessions exist in both subspecies virescens and grisea.

关键词： forage rangeland seed germination seed quality

Modeling temperature and moisture dependent emissions of carbon dioxide and methane from drying dairy cow manure

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Frontiers of agricultural Science and Engineering 2018年第2期5卷 280-286页

作者： Enzhu HU Pakorn SUTITARNNONTR Markus TULLER Scott B.JONES Institute of Resources and Environmental Sciences School of Metallurgy Northeastern University Department of Plants Soils and Climate Utah State University Department of Soil Water and Environmental Science The University of Arizona

Greenhouse gas emissions due to biological degradation processes of animal wastes are significant sources of air pollution from agricultural areas. The major environmental controls on these microbe-induced gas fluxes are temperature and moisture content. The objective of this study was to model the effects of temperature and moisture content on emissions of CO2 and CH4 during the ambient drying process of dairy manure under controlled conditions. Gas emissions were continuously recorded over 15 d with paired fully automated closed dynamic chambers coupled with a Fourier Transformed Infrared gas analyzer. Water content and temperature were measured and monitored with capacitance sensors. In addition, on days 0, 3, 6, 9, 12 and 15, p H, moisture content, dissolved organic carbon and total carbon(TC) were determined. An empirical model derived from the Arrhenius equation confirmed high dependency of carbon emissions on temperature and moisture content. Results indicate that for the investigated dairy manure, 6.83% of TC was lost in the form of CO2 and 0.047% of TC was emitted as *** the effect of temperature, the moisture contents associated with maximum gas emissions were estimated as0.75 and 0.79 g$g–1 for CO2 and CH4, respectively.

关键词： carbon dioxide dairy manure methane moisture temperature

From physics to fixtures to food:current and potential LED efficacy

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Horticulture Research 2020年第1期7卷 2271-2279页

作者： Paul Kusuma P.Morgan Pattison Bruce Bugbee Crop Physiology Laboratory Utah State UniversityLogan 84341 UTUSA Solid state Lighting Services Johnson City 37604 TNUSA

Overview Light-emitting diodes(LEDs)have enabled a historic increase in the conversion of electric energy to photons,but this is approaching a physical *** theoretical maximum efficiency occurs when all input energy is converted to energy in photosynthetic *** LEDs can be 93%efficient,phosphor-converted“whites”76%efficient,and red LEDs 81%*** improvements open new opportunities for horticultural lighting.

关键词： diodes phosphor approaching

The dry and hot American Southwest under the present and future climates

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Atmospheric and Oceanic Science Letters 2023年第6期16卷 48-51页

作者： Wei Zhang Department of Plants Soils and ClimateUtah State UniversityLoganUTUnite States Ecology Center Utah State UniversityLoganUTUnite States

由于正在持续的特大干旱,更频繁的洪水,热浪以及导致空气污染的山火,美国西南部目前正在经历气候危机.这些气候危机主要与水文气候过程相关,尤其是气候系统各圈层之间的水汽通量.本研究主要讨论目前一些水文系统的科学基站以及物理驱动... 详细信息

由于正在持续的特大干旱,更频繁的洪水,热浪以及导致空气污染的山火,美国西南部目前正在经历气候危机.这些气候危机主要与水文气候过程相关,尤其是气候系统各圈层之间的水汽通量.本研究主要讨论目前一些水文系统的科学基站以及物理驱动因素,比如北美夏季风以及太平洋北美遥相关.本研究指出降水以及气温对于干旱的相对作用的理论和工具.确定内部变率和外部强迫对于美国西南部水文气候系统的相对作用尤为重要.展望未来,需要研究高分辨率模拟系统,加强降水以及温度对于水文气候系统相对作用的理解,外部强迫的作用以及通过科学家以及其他利益相关者之间的合作.

关键词：美国西南部热浪干旱气候变化内部变率外部强迫