bluuebunny/crossref_metadata_2025_split huggingface dataset:
LONG‐TERM CHANGES IN STREAMFLOW FOLLOWING LOGGING IN WESTERN OREGON AND ASSOCIATED FISHERIES IMPLICATIONS1
Authors: Hicks Brendan J. , Beschta Robert L. , Harr R. Dennis. 
Published: June 2007

ABSTRACT: The long‐term effect of logging on low summer streamflow was investigated with a data set of 36 years. Hydrologic records were analyzed for the period 1953 and 1988 from Watershed (WS) 1 (clear‐cut logged and burned), WS 2 (unlogged control), and WS 3 (25 percent patch‐cut logged and burned) in the H. J. Andrews Experimental Forest, western Cascade Range, Oregon. These records spanned 9–10 years before logging, and 21–25 years after logging and burning. Streamfiows in August were the lowest of any month, and were unaffected by occasional heavy rain that occurred at the beginning of summer. August streamfiows increased in WS 1 compared to WS 2 by 159 percent following logging in WS 1, but this increase lasted for only eight years following the start of logging in 1962. Water yield in August for 1970–1988 observed from WS 1 was 25 percent less than predicted from the control (WS 2, ANOVA, p=0.032).Water yield in August increased by 59 percent after 25 percent of the area of WS 3 was patch‐cut logged and burned in 1963. In contrast to WS 1, however, water yields from WS 3 in August were consistently greater than predicted for 16 years following the start of logging, through to 1978. For the 10 years, 1979–1988, water yield observed in August from WS 3 was not different than predicted from the control (WS 2, ANOVA, p‐0.175).The contrasting responses of WS 1 and 3 to logging are thought to be the result of differences in riparian vegetation caused by different geomorphic conditions. A relatively wide valley floor in WS 1 allowed the development of hardwoods in the riparian zone following logging, but the narrow valley of WS 3 and limited sediment deposits prevented establishment of riparian hardwoods.Low streamflows during summer have implications for salmonid survival. Reduced streamflow reduces the amount of rearing habitat, thus increasing competition. Combined with high water temperatures, reduced streamflow can lead directly to salmonid mortality by driving salmonids from riffles and glides, and trapping them in drying pools. Low streamflow also increases oxygen depletion caused by leaves from riparian red alders.
TRUNCATED DISTRIBUTIONS IN HYDROLOGIC ANALYSIS1
Authors: Loaiciga Hugo A. , Michaelsen Joel , Hudak Paul F 
Published: June 2007

ABSTRACT: Truncated samples arise in a variety of hydrologic situations in which certain values of the variables of interest are unobservable. Remotely sensed data, for example, are truncated below the resolution level of the sensor: all objects smaller than the resolution of the instrument are not detected and their characteristics cannot be recorded. Many other situations occur in hydrologic studies where a sampling procedure or method yields truncated samples. The main results on this work on truncated samples are: (1) a general expression for the probability distribution function of a truncated random variable; (2) a description of the effect of truncation on the distribution function of several important probability models and on their parameters; and (3) development of a parameter estimation methodology for parameter estimation from truncated samples.From the theoretical results of this paper and the analysis of drought‐related data, we have concluded that: (1) truncated sampling can be advantageous, especially when certain ranges of values are difficult or impossible to observe; (2) the developed method for truncated sample analysis leads to efficient and accurate parameter estimation and statistical inference on truncated data; and (3) the developed method for truncated sample analysis can also yield the parameters and the distribution of the entire population when only a subset of that population is observable.
THE ROLE OF AGRICULTURAL GROUNDWATER CONSERVATION IN ACHIEVING ZERO OVERDRAFT IN ARIZONA1
Authors: Cory Dennis C. , Evans Mark E. , Leones Julie P. , Wade James C. 
Published: June 2007

ABSTRACT: The elimination of groundwater overdraft was a key feature of the 1980 Arizona Groundwater Management Act. To achieve this goal, the Arizona Department of Water Resources identified several Active Management Areas and developed urban, industrial, and agricultural water conservation plans. This study examines the reductions in groundwater use through agricultural water conservation in the Phoenix Active Management Area (AMA).Linear programming models are developed to analyze changes in groundwater use and net returns to agriculture over a 38‐year period, 1990 to 2025, for farming areas in the Phoenix AMA. Results indicate that the agricultural conservation program provides only modest groundwater savings under a wide range of scenarios. The low level of savings is partly due to the current economically efficient use of water. Other policy measures such as retiring agricultural land may be necessary if the Phoenix AMA is to meet its overdraft reduction goals; even if urban water conservation goals are met.
SPATIAL ANALYSIS FOR MONTHLY RAINFALL IN SOUTH FLORIDA1
Authors: Abtew W. , Obeysekera J. , Shih G. 
Published: June 2007

ABSTRACT: Several methods have been developed to interpolate point rainfall data and integrate areal rainfall data from any network of stations. From previous studies, it can be concluded that models for spatial analysis of rainfall are dependent on topography, area of analysis, type of rainfall, and density of gauging network. The purpose of this study is to evaluate a set of six appropriate models for point and areal rainfall estimations over a 4000 square mile area in South Florida.In this study, a case of developing spatial continuity model for monthly rainfall from a database that had various lengths of records and missing data is documented. The spatial correlation and variogram models for monthly rainfall were developed. Six methods of spatial interpolation were applied and the results validated with historical observations. The results of the study indicate that the multiquadric, kriging, and optimal interpolation schemes are the best three methods for interpolation of monthly rainfall within the study area. The optimal and kriging methods have the advantage of providing estimates of the error of interpolation. The optimal interpolation method uses the spatial correlation function and the kriging method uses the variogram function. The two spatial functions are related. Either of the two methods provide good estimates of monthly point and areal rainfall in the study area.
RURAL HOUSEHOLD RESPONSE TO WATER CONTAMINATION IN WEST VIRGINIA1
Authors: Collins Alan R. , Steinback Scott 
Published: June 2007

ABSTRACT: About one‐third of all West Virginians obtain domestic water from private water wells. In this research, mail and telephone surveys were used to investigate household responses to bacteria, mineral, and organic chemical contamination of domestic water supplies. Of households who were informed of contamination and acknowledged the problem, over 85 percent took action to avoid exposure to water contamination problems. The most common action was to clean and/or repair the water system (55.9 percent of valid surveys). Approximately 45 percent of households made investments of either a water treatment system, a new water source, or correction of contamination source. The average, annual economic cost of rural household actions was $320 for bacteria, $357 for minerals, and $1,090 for organic contamination. These economic costs represent a lower bound estimate for rural household willingness‐to‐pay (WTP) for a reduction in domestic water contamination from government action. On average, investment actions had lower annual economic costs than noninvestment actions of boiling and hauling water so that households who undertook investment actions in response to water contamination would have a lower WTP for government action to reduce water contamination.When effectiveness of water treatment systems was evaluated, treatment systems which require minimal household maintenance were found to reduce exposure to water contamination to safe levels as households intended when they installed the system. Treatment systems which were commonly ineffective included those which required continual maintenance (e.g., chiorinators) or were not designed to solve the contaminant problem for which they were purchased (e.g., filter systems for bacteria).
UTILIZATION OF A GEOGRAPHIC INFORMATION SYSTEM TO IDENTIFY THE PRIMARY AQUIFER PROVIDING GROUND WATER TO INDWIDUAL WELLS IN EASTERN ARKANSAS1
Authors: Baker Nancy T. 
Published: June 2007

ABSTRACT: A Geographic Information System (GIS) was used to develop an automated procedure for identifying the primary aquifers supplying ground water to individual wells in eastern Arkansas. As mandated by state law, water‐use data are reported by ground‐water withdrawers annually to the Arkansas Soil and Water Conservation Commission, and stored in the Arkansas Site‐Specific Water‐Use Data System provided and supported by the U.S. Geological Survey. Although most withdrawers are able to provide the amount of water withdrawn and the depth of their wells, very few are able to provide the name of the aquifer from which they withdraw water.GIS software was used to develop an automated procedure for identifying the primary aquifers supplying ground water to individual wells in eastern Arkansas. The software was used to generate a spatial representation of the bottom boundary for the Mississippi River Valley alluvial aquifer (the shallowest aquifer) in eastern Arkansas from well log‐data collected by the U.S. Geological Survey. The software was then used to determine the depth of the aquifer bottom at reported well locations to ascertain whether the Mississippi River Valley alluvial aquifer or a deeper aquifer was the primary aquifer providing water to each well. The alluvial aquifer was identified as the primary aquifer for about 23,500 wells.
A GEOGRAPHIC INFORMATION SYSTEM PROCEDURE TO QUANTIFY DRAINAGE‐BASIN CHARACTERISTICS1
Authors: Eash David A. 
Published: June 2007

ABSTRACT: The Basin Characteristics System (BCS) has been developed to quantify characteristics of a drainage basin. The first of four main BCS processing steps creates four geographic information system (GIS) digital maps representing the drainage divide, the drainage network, elevation contours, and the basin length. The drainage divide and basin length are manually digitized from 1:250,000‐scale topographic maps. The drainage network is extracted using GIS software from 1:100,000‐scale digital line graph data. The elevation contours are generated using GIS software from 1:250,000‐scale digital elevation model data. The second and third steps use software developed to assign attributes to specific features in three of the four digital maps and analyze the four maps to quantify 24 morphometric basin characteristics. The fourth step quantifies two climatic characteristics from digitized State maps of precipitation data.Compared to manual methods of measurement, the BCS provides a reduction in the time required to quantify the 26 basin characteristics. Comparison tests indicate the BCS measurements are not significantly different from manual topographic‐map measurements for 11 of 12 primary drainage‐basin characteristics. Tests indicate the BCS significantly underestimates basin slope. Comparison‐measurement differences for basin slope, main channel slope, and basin relief appear to be due to limitations in the digital elevation model data.
HYDRODYNAMIC SIMULATIONS OF A CONSTRUCTED WETLAND IN SOUTH FLORIDA1
Authors: Guardo Mariano , Tomasello Richard S. 
Published: June 2007

ABSTRACT: This paper describes the application of the SHEET2D model to the Florida's Everglades Nutrient Removal (ENR) Project. The ENR Project is a 3815 acre (1545 ha) pilot project, located in Palm Beach County. The operation of the treatment system will be used to demonstrate the performance of larger scale constructed wetland systems for removal of phosphorus from Everglades Agricultural Area (EAA) stormwater runoff. It is currently the largest stormwater wetland treatment system in the world.The SHEET2D model was used to analyze the performance of the ENR Project. SHEET2D is a two‐dimensional, depth‐averaged hydrodynamic model that is applicable to shallow water flow conditions. Subsequently, results from SHEET2D simulations were used to develop the ENEMOD model. ENRMOD is a lumped parameter box water quality model that can be used to analyze the long term performance of the ENR project with respect to hydrology and phosphorus uptake. Localized short‐circuiting in the agricultural ditches within the project area was analyzed by using the RBFVM‐2D model, which is a finite volume hydrodynamic model that is also applicable to shallow water flow conditions.The SHEET2D model was employed to simulate the hydraulics of the structures between cells and the hydrodynamics of the sheet‐flow moving across the buffer cell and treatment cells. Collection, distribution, and larger discharge canals within the project were simulated by means of the MultiBasin Routing (MBR) model features that are built into the SHEET2D model. Constant inflows (75 to 600 cfs [2.1 to 17 m3/s]) were used in all runs to simulate the discharge of the ENR Project based on the proposed operating schedule for the outflow pump station. The model simulated 30 days to reach steady state conditions. Under steady state conditions, the hydraulic retention times were computed for the project and the split of flow between the two treatment trains of the entire project from the common buffer cell. Additionally, design components such as height of the levees, capacity of the structures, and hydrographs at specified grids were obtained.
COUNTY COMMISSIONERS' WATER KNOWLEDGE1
Authors: Berry Kate A. , Markee Nancy L. , Stewart Michael J. , Giewat Gary R. 
Published: June 2007

ABSTRACT: This study examines the social construction of county commissioners' knowledge about water. Factors that influence what commissioners know about water include each commissioner's personal characteristics, education, experience in natural resources management, involvement in policy making, and use and evaluation of various sources of information. This study focused on county commissioners representing rural, mixed, and urban counties in Arizona, Nevada, and Utah and collected data through mail surveys and interviews.County commissioners in the survey were well educated; however, few had taken college courses directly addressing technical, management, or legal aspects of water issues. Approximately one‐third had direct experience in farming and ranching; nearly two‐thirds indicated that farming and ranching played a major role in their communities. Respondents had experience with a broad range of water policy issues. In evaluating thirteen information sources in terms of their frequency of use, relevancy, and reliability, respondents assessed fellow commissioners and local government staff and managers most positively and nonprofit organizations most negatively. The media was also broadly rated as less relevant and reliable than other sources of information. The commissioners in the study expressed a high level of general concern about water issues and a strung preference for local sources of information.
RECYCLING INPUT DATA DURING ANALYTIC ELEMENT MODELING NEAR INDIANAPOLIS, INDIANA1
Authors: Wittman Jack , Haitjema Henk , Studebaker Larry 
Published: June 2007

ABSTRACT: Overlapping and adjacent ground water investigations are common in areas where aquifers are threatened by industrial development. In the Indianapolis area in Marion County, Indiana, a patchwork of ground water flow models have been used during the past 20 years to evaluate ground water resources and to determine the effects of local contamination. In every case these ground water models were constructed from scratch.Site specific finite difference grids or finite element meshes inhibit the direct reuse of input data when the area of interest shifts. Because the aquifer is not discretized into a grid or mesh with analytic element models, there are unique opportunities for direct reuse of model input data. In two applications of this principle we illustrate how the newly emerging analytic element method allows a fairly straightforward reuse of model input data from previous models in the same general area. In analytic element models of Central Indiana, streams and their tributaries are represented in different resolutions. Input data items of several modeling studies are stored and cataloged on disk in such a manner that they can be selectively retrieved by a data management program PREPRO. In this manner, a new ground water model can be set up quickly with input data which have been previously defined and tested during model calibration.
CHARACTERIZATION OF TOXIC CONDITIONS ABOVE WILSON'S CREEK NATIONAL BATTLEFIELD PARK, MISSOUR1
Authors: Pulley Trudy Steidl , Nimmo Del Wayne R. , Tessari John D. 
Published: June 2007

ABSTRACT: Wilson's Creek has an extensive history of toxicity from both point and nonpoint sources. Seven‐day chronic daphnid (Ceriodaphnia dubia) bioassays identified one toxic site in the Wilson's Creek watershed. Procedures for the characterization phase of a Toxicity Identification Evaluation (TIE) were modified for chronic assessment and performed on four water samples from the toxic site. The characterization involved chemical/physical alterations of samples, combined with bioassays, to help in identification of the class(es) of toxicants; followed by chemical analyses. To help understand the additivity of mixtures, toxic units were derived. Successive samples contained concentrations of copper, cadmium, nickel and zinc that literature values describe as being chronically toxic to daphnids. Summed chronic toxic units for these values greatly exceeded ambient toxic units, and more than accounted for observed toxicity.Substantial fluctuations in water quality occurred over the five sampling periods of the characterization studies and a Test of Methods, June through August, 1991. This variability illustrates the difficulty in detecting and documenting nonpoint sources of pollution. Tests using living organisms, in conjunction with toxicity identification methods, on samples taken over time appear to be appropriate for detecting acute and chronic toxicity in areas impacted by intermittent point and nonpoint‐source toxicity.
RELATIONSHIPS BETWEEN LAND USES AND RAINWATER QUALITY IN A SOUTHCENTRAL PENNSYLVANIA WATERSHED1
Authors: Shertzer Richard H. , Hall David W. , Steffy Scott A. , Kime Rodney A. 
Published: June 2007

ABSTRACT: Spatial and temporal variability in rainfall concentrations of nutrients, major ions, and herbicides was monitored at 7 locations in or near the Conodoguinet Creek watershed in south‐central Pennsylvania from 1991.1993. Results were used to (1) compare precipitation quality in forested, agricultural and urban areas, and (2) assess the practicality of using volunteer citizen monitoring in such a study.As indicated in previous studies, sulfate and nitrogen concentrations in precipitation were linked to sample pH. Concentrations of major ions in precipitation appeared to relate more to regional influences rather than local influences. However, concentrations of herbicides in precipitation may have been influenced by both regional and local use which caused compounds like atrazine, deethylatrazine, propazine, simazine, metolachior, alachlor, ametryn, and prometon to be present in detectable concentrations in rainfall.Seasonality was evident in nitrogen, sulfate, pH, and herbicide data and was suggested in calcium, iron, manganese, magnesium, orthophosphate, and chloride data. Agricultural weed control activities were probably responsible for the seasonal pattern in pesticide data which peaked in May and June. Tropical storm Danielle may have caused the apparent seasonal patterns for the other nine parameters. This storm did not follow the typical west to east movement pattern and consequently produced rainfall of relative high quality.A variety of quality assurance checks indicated that trained volunteer citizen monitors were successful participants in this intensive and extensive scientific study, collecting good quality samples in a timely manner. Without this kind of volunteer help, it is extremely difficult to complete studies that require sampling in response to natural events such as rainfall.
EXTERNALITIES, WATER PRICES, AND WATER TRANSFERS1
Authors: Jordan Jeffrey L. 
Published: June 2007

ABSTRACTDiscussing, estimating or analyzing the value of water is a difficult task. In addressing the value of water as reflected in its price — either as charged by a water utility, as the price of a water transfer, or a water sale in some market — this paper will examine three propositions regarding water pricing. The paper will consider the marginal scarcity rent of water, estimates of externalities, the full cost pricing of water and the consequences of these considerations on water prices, transfers and the efficiency of water use.
BENEFITS FROM MANAGING FARM PRODUCED NUTRIENTS1
Authors: Ogg Clayton 
Published: June 2007

ABSTRACTManures and fertilizers are applied to agricultural lands in excess of recommended amounts, resulting in widespread pollution of surface and ground water and contributing a substantial source of greenhouse gases associated with global warming. By developing policies that exploit the value of farm produced nutrients, input costs can be minimized. Better accounting for or crediting of farm produced nutrients is leading to economically beneficial conservation of fertilizer. In addition, hog producers who own enough land may benefit from properly managing manure nutrients. Poultry litter is valuable as fertilizer and can be marketed by independent dealers to farmers in nutrient deficit areas, with very modest assistance from the government. Dairy producers may modify their past income support programs to finance central compost facilities. Although nutrient problems were neglected in the past, recent Federal initiatives and joint initiatives with states exploit many of these and other opportunities to avoid excessive application of nutrients to the land.
ESTIMATING ATRAZINE LEACHING IN THE MIDWEST1
Authors: Burkart Michael R. , Gassman Philip W. , Moorman Thomas B. , Singh Piyash 
Published: June 2007

ABSTRACTData from seven Management Systems Evaluation Areas (MSEA) were used to test the sensitivity of a leaching model, Pesticide Root Zone Model‐2, to a variety of hydrologic settings in the Midwest. Atrazine leaching was simulated because it was prevalent in the MSEA studies and is frequently detected in the region's groundwater. Short‐term simulations used site specific soil and chemical parameters. Generalized simulations used data avail. able from regional soil databases and standardized variables. Accurate short‐term simulations were precluded by lack of antecedent atrazine concentrations in the soil profile and water, suggesting that simulations using data for less than five years underestimate atrazine leaching. The seven sites were ranked in order of atrazine detection frequency (concentration > 0.2 μg L‐1) in soil water at 2 m depth in simulations. The rank order of the sites based on long‐term simulations were similar to the ranks of sites based on atrazine detection frequency from groundwater monitoring. Simulations with Map Unit Use File (MUUF) soils data were more highly correlated with ranks of observed atrazine detection frequencies than were short‐term simulations using site‐specific soil data. Simulations using the MIJUIF data for soil parameters were sufficiently similarity to observed atrazine detection to allow the credible use of regional soils data for simulating leaching with PRZM‐2 in a variety of Midwest soil and hydrologic conditions. This is encouraging for regional modeling efforts because soil parameters are among the most critical for operating PRZM‐2 and many other leaching models.