Colorado Case Study Research Articles

Landscape dynamics at the public–private interface: A case study in Colorado

The Rocky Mountain West is experiencing rapid land use change in the form of residential development. Public land managers, like the U.S. Forest Service, Bureau of Land Management, and National Park Service are increasingly concerned with ecological and management implications of private land use adjacent to public lands. Using fine-grain land use data, collected from high resolution aerial photographs, we quantify human land use composition, patterns, and trends at the interface of public and private land in the Southern Rocky Mountain Ecoregion (SRE) of Colorado. We developed two metrics for assessing land use impacts. The first quantifies the amount of land cover modified (HM c) by human land use and the second estimates the amount of wildlife habitat that is functionally modified (HM fd). In 2005, we estimate that human land use modifies 8% of the total land cover in the Colorado SRE and that 13% of the study area was functionally modified. Agriculture had the greatest impact in terms of area of modified land cover (282,305 ha). Residential (exurban) land use had a smaller footprint (HM c) but the close proximity to public lands, dispersed spatial pattern (high HM fd), and rapid increase in rural and exurban housing density observed in the SRE have important implications. This research demonstrates how fine scale land cover data can be used to examine land use pattern and composition as well as track land use change.

Adaptation and Application of Federal Capabilities-Based Planning Models to Individual States: State of Colorado Case Study

This article utilizes the State of Colorado as a case study in how individual states are adapting and applying federal capabilities-based planning models to their homeland security programs. The article reviews the corrective change in direction taken by Colorado in implementation of homeland security organizational strategies, structures, policies and procedures. The authors' findings lead to conclusions about Colorado's beginning phase of transforming deficient homeland security strategy, incoherent organization, and fragmented planning processes into sound strategy, focused structure, and organized methods. In November 2008, the Center for Homeland Security (CHS) at the University of Colorado at Colorado Springs began a research and mutual support effort with the Colorado Governor's Office of Homeland Security for the purpose of immersing in the state's revitalized homeland security planning cycle. The intent was to gain insight into the state's creation of a new homeland security organization, the application of a new homeland security strategy, and the efficacy of implementing federal capabilities-based planning processes from a strategic and operational perspective, rather than a federal grant application focus. Colorado's shift to a capabilities-based planning process was largely in response to criticism from both the Department of Homeland Security and Colorado state auditors on the use of federal homeland security funds. Audits described the state's strategy as disorganized and its homeland security structure as fractured with poor accountability and little meaningful oversight. This article examines the initial findings of the CHS immersion experience.

Temperature, Toxicity and Regulation: A Colorado Case Study

Temperature, Toxicity and Regulation: A Colorado Case Study

Using digitized primary source materials in the classroom: A Colorado case study

Using digitized primary source materials with K–12 students makes learning content more engaging and relevant, and helps students develop a wide range of skills. This paper highlights the use of primary source materials in Colorado classrooms and provides a brief overview of what educators’ needs are in order to use digitized primary source materials more efficiently and effectively with students.

An Economic Analysis of the Cost-Effectiveness of Privatizing Additional Production of Catchable Rainbow Trout: A Case Study in Colorado

Abstract This study examines the cost of increasing state production of catchable rainbow trout Oncorhynchus mykiss and compares this cost with the cost of purchasing fish from private producers in Colorado. The results suggest that the scope of the analysis and the manner in which costs are identified will determine whether purchasing fish can result in cost savings. When the scope of the study is the state and reported state costs are used, purchasing fish could result in a loss of US$0.53/lb. When the scope of the study is the state and opportunity costs are estimated, purchasing could result in a loss of as much as $0.02/lb or a savings of as much as $0.51/lb. When the scope of the study is the nation, and opportunity costs are estimated, purchasing could result in cost savings of $1.71–2.24/lb. Further research is needed to determine whether private producers are a reliable source of supply and to assess the quality of the rainbow trout purchased from private producers.

Impact of irrigation timing on simulated water-crop production functions

Estimates of the effects of alternative discrete irrigation water scheduling options on consumptive use or evapotranspiration and on crop yield are developed for a northeastern Colorado case study. The analysis proceeds from the premise that farmers, rather than considering irrigation water as a continuously variable input, tend to treat irrigations as discrete events, and make scheduling decisions as choices among numbers of irrigations of approximately equal volume. The van Genuchten-Hanks model is employed to develop a transient-state water-crop production function model. Results for two crops – corn grain and edible dry beans – are presented here. Findings are that the effect of the number of irrigations on evapotranspiration and yield per hectare varies widely, depending upon the timing of applications. When farmers can choose the optimal timing of irrigations, a reduced number of irrigations has a relatively limited adverse effect on crop production until irrigations are reduced to less than four per season. However, there are many situations in which an inability to apply water can result in a very large reduction from potential maximum yield, particularly if water is withheld early in the season and/or during the rapid growth period of the crops. In many contexts of irrigation water management, water policy analysts will wish to consider the more realistic discrete-input simulation model for policy evaluation.

Use of 234 U and 238 U isotopes to evaluate contamination of near-surface groundwater with uranium-mill effluent: a case study in south-central Colorado, U.S.A.

The 234U/238U alpha activity ratio (AR) was determined in 47 samples of variably uraniferous groundwater from the vicinity of a uranium mill near Canon City, Colorado. The results illustrate that uranium isotopes can be used to determine the distribution of uranium contamination in groundwater and to indicate processes such as mixing and chemical precipitation that affect uranium concentrations. Highly to moderately contaminated groundwater samples collected from the mill site and land immediately downgradient from the mill site contain more than 100 μg/l of dissolved uranium and typically have AR values in the narrow range of 1.0–1.06. Other samples from the shallow alluvial aquifer farther downgradient from the mill contain 10–100 μg/l uranium and plot along a broad trend of increasing AR (1.06–1.46) with decreasing uranium concentration. The results are consistent with mixing of liquid mill waste (AR≈1.0) with alluvial groundwater of small, but variable, uranium concentrations and AR of 1.3–1.5. In the alluvial aquifer, the spatial distribution of wells with AR values less than 1.3 is consistent with previous estimates of the probable distribution of contamination, based on water chemistry and hydrology. Wells more distant from the area of probable contamination have AR values that are consistently greater than 1.3 and are indicative of little or no contamination. The methodology of this study can be extended usefully to similar sites of uranium mining, milling, or processing provided that local geohydrologic settings promote uranium mobility and that introduced uranium contamination is isotopically distinct from that of local groundwater.

Natural or fertilizer-derived uranium in irrigation drainage: a case study in southeastern Colorado, U.S.A.

Drainage from heavily cultivated soils may be contaminated with U that is leached from the soil or added as a trace constituent of PO 4-based commercial fertilizer. The effect of decades-long application of U-rich fertilizer on the U concentration of irrigation drainage was investigated in a small (14.2 km 2) drainage basin in southeastern Colorado. The basin was chosen because previous reports indicated locally anomalous concentrations of dissolved NO 3 (6–36 mg 1 −1) and dissolved U (61 pg 1 −1) at the mouth of the only stream. Results of this study indicated minimal impact of fertilizer-U compared to natural U leached from the local soils. Detailed sampling of the stream along a 6 mile (9.7 km) reach through heavily cultivated lands indicated marked decoupling of the buildup of dissolved NO 3 and U. Dissolved U increased markedly in the upstream half of the reach and correlated positively with increases in Na, Mg, SO 4, B and Li derived from leaching of surrounding shaley soils. In contrast, major increases in dissolved NO 3 occurred farther downstream where stream water was heavily impacted by ground water return from extensively fertilized fields. Nitrogen isotopic measurements confirmed that dissolved NO 3 originated from fertilizer and soil organic N (crop waste). Uranium isotopic measurements of variably uraniferous waters showed little evidence of contamination with fertilizer-derived U of isotopically distinct 234U/ 238U alpha activity ratio (A.R. = 1.0). Leaching experiments using local alkaline soil, irrigation water and U-rich fertilizer confirmed the ready leachability of soil-bound U and the comparative immobility of U added with liquid fertilizer. Relatively insoluble precipitates containing Ca P U were formed by mixing liquid fertilizer with water containing abundant dissolved Ca. In the local soils soluble Ca is provided by dissolution of abundant gypsum. Similar studies are needed elsewhere because the mobility of fertilizer-derived U is dependent on fertilizer type, porewater chemistry and soil properties (pH, moisture, mineralogy, texture).

Undesirable Lag Effects in Tourist Destination Development: A Colorado Case Study

Tourism planners often promise widespread community renewal as a product of tourism development, but benefits do not always occur as expected. This article analyzes undesirable "lag effects " associated with early stages of tourist destination development. Examples from two Colorado gaming towns illustrate the problems; hypotheses formalizing relationships between temporal problems and community tourism development are derived.

Rural implications of a needs assessment of physical educators with mainstreamed disabled students: A case study in Colorado

Results of a physical education needs assessment survey in the state of Colorado were compiled to determine comparative needs of rural and non-rural teachers and programs. Five hundred and eighty teachers were surveyed, 87 of whom served in rural areas. Physical educators in rural areas had the least number of disabled students in regular classrooms, yet were the most involved teachers in the placement process. Rural physical educators were the most likely to share their financial resources with programs for the disabled, but had the smallest budgets from which to draw funds. They also did the best overall job of partici-pating in the IEP process, yet seemed least trained in assessment and evaluation.

Evolution of the San Juan Basin, Colorado, and New Mexico Basin Analysis Case Study: ABSTRACT

During 1985 to 1989, the US Geological Survey conducted a basin analysis study that investigated the sedimentological and structural history of the San Juan basin and vicinity. The San Juan basin is a large asymmetric basin in southwest Colorado and northwest New Mexico near the southeastern edge of the Colorado Plateau. It formed as a result of northeast-directed compression coupled with a slight northeastward shift of the Colorado Plateau during the Late Cretaceous to Oligocene Laramide orogeny. Although the basin assumed its final configuration during the Laramide orogeny, regional stratigraphic and sedimentologic studies show that uplifts active during the Laramide orogeny were also active in the geologic past. Analysis of 1,000 mi of reflection seismic data defines a rectilinear pattern of northwest- and northeast-trending faults that involved the Precambrian basement in basin development. Middle Pennsylvanian to Late Permian, Middle to Late Jurassic, Early Cretaceous, Late Cretaceous-Oligocene, and Miocene were major times of movements on the faults and/or bounding uplifts. Preserved Mesozoic and older sedimentary rocks in the basin accumulated as part of widespread regional depositional systems. Pennsylvanian strata, consisting of a thick sequence of clastic and carbonate rocks, and evaporites deposited in both open and restricted marine environments contain significantmore » oil and gas resources. Mesozoic strata deposited in a variety of widespread continental and marine environments host 50% of the country's uranium reserves. Five marine transgressive-regressive cycles during the Cretaceous resulted in a thick sequence of intertonguing marine and continental rocks containing large resources of coal, oil, and gas.« less

The Effects of Electricity Rates and Rate Structures on Pump Irrigation: An Eastern Colorado Case Study

This article analyzes the effects of electricity rate policy on electricity demand (and the derived effect on irrigation water use) via a case study in eastern Colorado. Empirical demand curves for electricity for pump irrigation are estimated. Alternative rate structures are tested for their effect on electricity and water use patterns, farm income, and utility revenue. Particular attention is given to the problem of modeling a declining block structure. 11 references, 1 figure, 3 tables.