Filters: Types: ScienceBase Citation (X)164 results (187ms)
MOAB, Utah â€” Drier conditions projected to result from climate change in the Southwest will likely reduce perennial vegetation cover and result in increased dust storm activity in the future, according to a new study by scientists with the U.S. Geological Survey and the University of California, Los Angeles. The research team examined climate, vegetation and soil measurements collected over a 20-year period in Arches and Canyonlands National Parks in southeastern Utah. Long-term data indicated that perennial vegetation in grasslands and some shrublands declined with temperature increases. The study then used these soil and vegetation measurements in a model to project future wind erosion. The findings strongly...
Bromus tectorum} Invasion Alters Soil Microbial Carbon and Nitrogen Cycling in an Arid Colorado Plateau Grassland
Invasion by the C3 annual grass Bromus tectorum has significantly increased the amount of relatively low quality (high lignin:nitrogen) plant litter deposited in arid Colorado Plateau grasslands. Our objectives were to determine what effects these changes have on microbial utilization of carbon (C) and nitrogen (N). We measured net C and N mineralization, and the Î´13C of bulk organic matter, mineralized C, and bacterial fatty acids from soils of invaded and non-invaded C3 (Stipa hymenoides) and C4 (Hilaria jamesii) native grasslands. Carbon mineralization was greater in invaded compared to non-invaded sites (1.25 +/- 0.09 and 1.52 +/- 0.18 g CO2-C kg-1 soil h-1 respectively). Rates of net inorganic N mineralization...
Soil aggregates are groups of soil particles that are bound to each other more strongly than to adjacent particles. Organic matter â€œgluesâ€� produced when soil biota break down dead roots and litter hold the particles together. Threadlike strands of fungi also bind particles into aggregates. Microscopic aggregates are the building blocks of larger aggregates. The larger aggregates and the arrangement of them, along with chemical attraction between particles, determine soil structure. The structure of the surface layer commonly is granular or blocky, but a degraded surface layer can be crusted, platy, or structureless. Pores important for the movement of air, water, and plant nutrients occur within and between...
The purpose of this study was to obtain baseline data about small mammal prey based communities on Carson National Forest, especially with regards to prey of Northern Goshawk and Mexican Spotted Owl. Published in Final Report submitted to Carson National Forest, Taos, New Mexico, on pages 48 - 48, in 2003.
Categories: Publication; Types: Citation, ScienceBase Citation; Tags: Final Report submitted to Carson National Forest, Taos, New Mexico
Study on the cattle industry in Canyonlands National Park. The intention of the study is to trace the history of the cattle industry as it was done in the park. The study is divided into three sections: 1) discussion of the open range cattle industry in the last decades of the 19th century 2) a look at the park itself, the topography, Colorado and Green Rivers and 3) a look at the land in the park located between the rivers, Island in the Sky and White Rim country. Published by Historic Preservation Team, Denver Service Center, National Park Service, U.S. Dept. of the Interior, in 1972.
In a survey study conducted to obtain base-line data, eleven extensive float trips were made down the Colorado River in the period from September 1970 through mid-June 1976. Samples of fish, mammals, plants and herpetofauna were collected; species collected are listed. In addition, terrestrial surveys were made at various land sites in the region. Major results of this survey were the lack of success in obtaining a speciman of the humpback sucker, xyrauchen texanus, and the discovery of the relative scarcity of chubs of the genus Gila. Both of these outcomes have been tied to the low water temperatures caused by releases from the Grand Canyon Dam, as well as to the barrier that the dam presents to upstream movement...
Categories: Publication; Types: Citation, ScienceBase Citation; Tags: Surveys | Fish populations | Arizona | Colorado Ri
Intensive non-native removal efforts from PNM Weir to Hogback Diversion (RM 166.6 â€“ 159.0) continued for the third consecutive year in 2003. These efforts initially began to assess efficacy of mechanical removal as an efficient method of decreasing the distribution and abundance of non-native fishes, with emphasis on channel catfish and common carp. These efforts have been recognized as a Recovery Action by the San Juan River Recovery Implementation Program (SJRIP).
The Colorado River cutthroat trout (Oncorhynchus clarkii pleuriticus) was once distributed throughout the colder waters of the Colorado River basin above the Grand Canyon. About 8 percent of its historical range is occupied by unhybridized or ecologically significant populations. It has been petitioned for listing under the Endangered Species Act and is accorded special status by several state and federal agencies. Habitat alteration and nonnative trout invasions led to the extirpation of many populations and impede restoration. Habitat fragmentation exacerbated by climate change is an emerging threat. A strategic, systematic approach to future conservation is likely to be the most successful.
The Colorado River Basin and Climatic Change : The Sensitivity of Streamflow and Water Supply to Variations in Temperature and Precipitation
Growing international concern about the greenhouse effect has led to increased interest in the regional implications of changes in temperature and precipitation patterns for a wide range of societal and natural systems, including agriculture, seal level, biodiversity, and water resources. The accumulation of greenhouse gases in the atmosphere due to human activities are likely to have siginificant, though still poorly understood, impacts on water quality and availability. One method developed over the last several years for determining how regional water resources might be affected by climatic change is to develop scienarios of changes in temperature and precipitation and to use hydrologic simulation models to study...
Rearing Razorback Sucker Sub-Adults at Dexter National Fish Hatchery and Technology Center, San Juan River, 2007
In September of 2004 Dexter staff responded to a request for proposals from the Bureau of Reclamation on behalf of the San Juan Recovery Implementation Program to rear and deliver 20,000 -200+ mm razorback sucker to existing grow-out ponds located on the Navajo Indian Irrigation Project (NAPI), near Farmington , NM. The fish would then be grown out for six months to a year in the NAPI ponds to reach the target size of 300+ mm in length before being released into the wild. The stockings would help the SJRIP meet its augmentation goals for the species in the San Juan River as described in addendum to The Five-Year Augmentation Plan For Razorbacks Sucker In The San Juan(Feb 2003).
Recommended Priorities for Geomorphology Research in Endangered Fish Habitats of the Upper Colorado River Basin
Activities of the Upper Colorado River Endangered Fish Recovery Program (Recovery Program) include habitat improvement and management (e.g., restoration of flooded bottomlands, provision of fish passage) and flow management to provide suitable habitat conditions for the four species of endangered fishes in the Upper Colorado River Basin â€” Colorado pikeminnow (Ptychocheilus lucius), humpback chub (Gila cypha), bonytail (Gila elegans), and razorback sucker (Xyrauchen texanus). In this report, we identify and apply an approach for prioritizing river reaches and habitats for geomorphic research in the Upper Colorado River Basin. The goal of this project was to identify priorities for geomorphology research in endangered...
The effect of campgrounds on small mammals in Canyonlands and Arches National Parks, Utah : final report
The effect of campgrounds on small mammals in Canyonlands and Arches National Parks, Utah : final report, credited to Workman, Gar W, published in 1977. Published by Dept. of Wildlife Science, Utah State University, in 1977.
The structural stabilization of seven prehistoric ruins in Canyonlands National Park and Natural Bridges National Monument
The structural stabilization of seven prehistoric ruins in Canyonlands National Park and Natural Bridges National Monument, credited to Gaunt, Joan K, published in 1985.
The Colorado River Basin and Climatic Change: The Sensitivity of Streamflow and Water Supply to Variations in Temperature and Precipitation| US EPA
Concern over the greenhouse effect has led to increased interest in the regional implications of changes in temperature and precipitation patterns for water resources. The impact of greenhouse gases on water availability and quality is likely to be significant, though still poorly understood. Both the development of scenarios involving temperature and precipitation variation and the use of hydrologic simulation models allows researchers to study the impact of these changes on runoff and water supply.
The primary objective of this effort was to investigate the feasibility of constructing 2-6 backwater habitats in the San Juan River between the Animas River confluence and the Hogback Diversion Dam for acclimating stocked young-of-year (YOY) and juvenile Colorado pikeminnow and subsequently increasing their survival and retention within the river. The goal was to identify at least 6 locations where suitable backwaters can be constructed with a total wetted surface area of 1,800 m2 or more (average of 300 m2 per backwater). If backwaters of this size could not be created, then smaller backwaters would be considered. The secondary objective was to increase the abundance of backwater habitat available for use by YOY...
An evaluation of fish entrainment into the Maybell Ditch on the Yampa River, Colorado, 2007 and 2008.
The Maybell Ditch is a gravity-fed diversion ditch in the Yampa River within occupied habitat for adult Colorado pikeminnow Ptychocheilus lucius, a federally listed endangered fish species. The objective of this study was to determine if Colorado pikeminnow or other fish are entrained in the Maybell Ditch. The ditch is approximately 12 miles (19 km) long and the uppermost 1.4 miles (2.2 km) was sampled for fish. The ditch was sampled with a bank electrofisher mounted in a canoe during two days in October, 2007 and with hoop nets set along ditch margins from June 19 through July 11, 2008. Sampling totaled 3.6 hours of electrofishing effort and 1,341 hours of hoop net sets.
Determination of a Safe Level of Ammonia that is Protective of Juvenile Colorado Pikeminnow in the Upper Colorado River, Utah
Used first paragraph of introduction: Various sections of the un-impounded portions of the Upper Colorado River above Lake Powell have been declared critical habitat (Fed. Reg. 59:13374-13400) for four endangered fish species: Colorado pikeminnow (Ptychocheilus lucius), razorback sucker (Xyrauchen texanus), humpback chub (Gila cypha), and bonytail chub (Gila elegans). The U.S. Fish and Wildlife Service (USFWS), under the auspices of Section 7 of the Endangered Species Act, must protect these species and determine if any private, state, or federal activities could jeopardize remaining populations of these endangered species.
There were 353 fish collections at 273 unique sites between river miles 141.2 and 3.6 resulting in the collection of fish representing six families and 14 species with all but five collections producing fish under the auspices of the 2004 larval Colorado pikeminnow and 2004 larval razorback sucker surveys.
A physical crust is a thin layer with reduced porosity and increased density at the surface of the soil. A biological crust is a living community of lichen, cyanobacteria, algae, and moss growing on the soil surface and binding it together. A chemical crust or precipitate is white or pale colored and forms in soils with a high content of salts. Both chemical and biological crusts can form on and extend into a physical crust. This information sheet deals only with physical and biological crusts.
Downstream transport rates of passively drifting particles in the San Juan River in 1998 : Draft Report
Colorado pikeminnow is a federally endangered species that has declined throughout its historical range which includes the San Juan River Basin. A factor that has been hypothesized to have contributed to the loss of Colorado pikeminnow is the downstream transport of their drifting larvae into unsuitable habitats. Until recently, the lack of a suitable drift material has precluded quantitative testing of this hypothesis. Passively drifting particles (=beads) were used as surrogates for drifting larval Colorado pikeminnow. Their rate of downstream transport (drift) was measured in July 1998 through different reaches of the San Juan River at moderate flows (ca. 2,000 cfs). The transport rates of beads were measured...