Digital Commons Network^™

The Distribution Of Plants In Scoska Cave, North Yorkshire, And Their Relationship To Light Intensity, Allan Pentecost, Zhang Zhaohui

International Journal of Speleology

The flora of a small limestone cave was investigated. A total of 59 species was recorded (4 algae, 3 lichens, 47 bryophytes, 4 ferns, 1 angiosperm) making it bryologically the richest cave in Britain and one of the richest in Europe. All but nine of the species had been recorded from other European caves. Species-richness declined irregullarly from the entrance (relative irradiance with respect to open sky 12%) to 34m depth (rel. irradiance 0.004%). Bryophytes were found at 0-16m depth where relative irradiance declined to 0.2% and only algae were encountered at 34m depth. While irradiance, which declined exponentially, was …

Studies On Certain Aspects Of Behaviour In The Blind Catfish Horaglanis Krishnai Menon, T. V. Anna Mercy, N. K. Pillai, N. K. Balasubramanian

International Journal of Speleology

Horaglanis krishnai is a blind catfish inhabiting the dug-out wells at Kottayam, Kerala. This fish has great zoogeographical importance as a similar blind clariid, Uegitglanis zammaroni is found only in the artesian wells of the former Italian Somaliland. Studies on certain behavioural aspects of the fish in captive conditions showed that, this fish even though is blind, exhibited a high degree of thigmotactism. Locomotion, comfort behaviour, feeding and light sensitivity of the fish were studied under laboratory conditions. Though the fish is totally blind and histological study did not reveal the presence of any light sensitive structures, the fish is …

Subsidence History Of The Rukwa Rift In South West Tanzania Analysed From Ivuna Well, E I Mbede

Tanzania Journal of Science

The variation in subsidence rate during rift basin development is a good indication for the Geodynamic history of a sedimentary basin. The sedimentary section of Ivuna Well is herein used to explain the structural evolution of Rukwa Basin within the Western Rift of the East African Rift System. The sedimentary record of Ivuna Well is extracted from published information. The effects of sedimentary load, corrected for compaction and variation in water depth, and lake-level have been removed to obtain the "tectonic subsidence." Curves show two phases of accelerated subsidence related to the fault controlled rifting phases: The Karoo rifting and …

Comparisons Of Gravity Anomalies At Pseudofaults, Fracture Zones, And Nontransform Discontinuities From Fast To Slow Spreading Areas, Sarah E. Kruse, Sarah F. Tebbens, David F. Naar, Qingyuan Y. Lou, Robert T. Bird

Geology Faculty Publications

Published mechanisms for rift tip propagation at spreading centers include extensional deformation and an initial period of slow spreading. We investigate whether the gravity signal and inferred crustal structure at pseudofaults formed in medium to superfast spreading environments resemble the gravity signal at fracture zones or nontransform discontinuities formed in slow spreading environments. We find that altimetry-based gravity anomalies on the Mathematician, Bauer, Easter, Juan Fernandez, and northern Chile Ridge pseudofaults, located in 75–150 mm/yr (full rate) seafloor spreading environments, are similar in amplitude and form to Atlantic fracture zones with 20–30 mm/yr spreading rates. A 5–15 mGal positive mantle …

Improving Water Quality Through Bmps For Crop Production Systems Whole Farm Soil And Water Management, J. T. Gilmour, L. R. Frye, N. A. Slaton

Arkansas Water Resources Center Technical Reports

The major objective of this demonstration project was to assess the usefulness of Global Positioning Systems/Geographic Information Systems (GPS/GIS), water testing, soil testing and yield monitoring in a whole farm water and soil management plan. An important part of this objective was to make recommendations to increase crop productivity and decrease the potential for surface water degradation through erosion and runoff at the farm. The farm was located on 2400 acres in the Bayou de View watershed in Monroe County, Arkansas. The farm lies approximately five miles southwest of the town of Brinkley straddling Highway 17 just south of its …

Predicted Land Use Changes In Agricultural Areas Of Wa And Resulting Impact On The Extent Of Dryland Salinity, C E. Mcconnell

Resource management technical reports

An assessment of current and possible future land use in Western Australia was undertaken as part of the National Land and Water Resources Audit. This data was used to assess the impact of land use change on the future extent of salinity. It was found that in some areas there is real capacity for changing land use to impact on recharge to the watertable.

Gis-Based Decision Support For Drained Wetland Resoration In The Eel River Watershed Of N. E. Indiana, Xiangheng Yang

All-Inclusive List of Electronic Theses and Dissertations

The objective of this research is to develop cost-effect and accurate methods to identify optimal restorable drained wetland cropland sites. Landsat Thematic Mapper (TM) data analysis was used to identify the potential cropland candidate sites in the initial step. The result of digital TM data analysis shows that the overall classification accuracy in identifying classes of potential restoration candidate hydric soils is 86.7%. This accuracy shows that the TM data digital analysis is a cost-effective method for identifying poorly drained cropland hydric soils potentially suitable for wetland conversiOn. To support multi-factorial analysis in the final site screening, a Spatial Decision …

A Simple Surface Temperature Assimilation Scheme For Use In Land Surface Models, Venkataraman Lakshmi

Faculty Publications

This paper examines the utilization of surface temperature as a variable which can be assimilated in off-line land surface hydrological models. The connection between the surface temperature and evapotranspiration is utilized in making adjustments to the model-computed surface soil moisture. This adjustment is a function of the difference between the model-computed and the observed surface temperature. Comparisons between the model-computed and satellite-observed surface temperatures have been carried out. The assimilation of surface temperature is carried out twice a day (corresponding to the A.M. and P.M. overpass of the NOAA 10) over the Red-Arkansas basin in the southwestern United States (31°50′N-36°N, …

New Kinematic Models For Pacific‐North America Motion From 3 Ma To Present, Ii: Evidence For A “Baja California Shear Zone”, Timothy Dixon, Fred Farina, Charles Demets, Francisco Suarez-Vidal, John Fletcher, Bertha Marquez-Azua, M. Meghan Miller, Osvaldo Sanchez, Paul Umhoefer

All Faculty Scholarship for the College of the Sciences

We use new models for present‐day Pacific‐North America motion to evaluate the tectonics of offshore regions west of the Californias. Vandenburg in coastal Alta California moves at the Pacific plate velocity within uncertainties (∼1 mm/yr) after correcting for strain accumulation on the San Andreas and San Gregorio‐Hosgri faults with a model that includes a viscoelastic lower crust. Modeled and measured velocities at coastal sites in Baja California south of the Agua Blanca fault, a region that most previous models consider Pacific plate, differ by 3–8 mm/yr, with coastal sites moving slower that the Pacific plate. We interpret these discrepancies in …

Eustasy Determination From Borehole Data, Onshore New Jersey: New Boreholes And New Porosity Estimates, William Alan Van Sickel

Masters Theses

Backstripping analysis of detailed stratigraphic data from the Bass River and Ancora boreholes on the New Jersey Coastal Plain (Ocean Drilling Project Leg 17 4AX) was conducted to test and refine previous eustatic estimates (Kominz et al., 1998) and provide new Upper Cretaceous estimates. Porositydepth relationships required by the backstripping method were estimated to supplement those from the Cost B-2 well (Rhodehamel, 1977). Sand and mud porosity at shallow depths (<500 m) obtained here are higher than was seen at the Cost B-2 well.

The Bass River and Ancora boreholes targeted older sequences of the Upper Cretaceous to Paleocene. This new data allow for more accurate estimate of the magnitude of long-term sea-level …

Ely Disrict Managed Natural And Prescribed Fire Plan, United States Department Of The Interior, Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

No abstract provided.

Magmatic Processes Operating During The Middle To Late Pliocene And Pleistocene Along The Transition Zone Near 43º North, Christy L. Lee

Dissertations and Theses

A geochemical and structural transition zone exists between the Cascades and Basin and Range provinces in Oregon. Geologic mapping in this area has allowed the definition of six volcanic rock sequences: 1) interfingered alkali-rich basaltic trachyandesite to trachydacite lava flows and low-alkali basaltic andesite lava flows, 2) HAOT lava flows, 3) basaltic andesite lava flows, 4) andesite lava flows and vent deposits with minor basaltic andesite lava flows, 5) HAB lava flows, and 6) interfingered basaltic andesite, andesite, and trachyandesite lava flows.

Geochemical models of sequence 1 alkali-rich rocks suggest the fractionation of the parent assemblage plag (An₅₅)+magn+ol±aug …

Chemical And Biological Trends During Lake Evolution In Recently Deglaciated Terrain, Daniel R. Engstrom, Sherilyn C. Fritz, James E. Almendinger, Stephen Juggins

Department of Earth and Atmospheric Sciences: Faculty Publications

As newly formed landscapes evolve, physical and biological changes occur that are collectively known as primary succession. Although succession is a fundamental concept in ecology, it is poorly understood in the context of aquatic environments. The prevailing view is that lakes become more enriched in nutrients as they age, leading to increased biological production. Here we report the opposite pattern of lake development, observed from the water chemistry of lakes that formed at various times within the past 10,000 years during glacial retreat at Glacier Bay, Alaska. The lakes have grown more dilute and acidic with time, accumulated dissolved organic …

Proceedings Of The Arkansas Water Resources Center Annual Conference: Environmental Hydrology, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

The papers and abstracts in these proceedings are the result of a joint conference of the Arkansas Water Resources Center (A WRC) with the SouthCentral Section of the Geological Society of America. The joint conference was a success with about 250 participants. A WRC sponsored two sessions on Environmental Hydrology and a short course titled "Hydrogeology and Geochemistry of Salt Water Contamination." The Environmental Hydrology presentations covered wide-ranging topics that reflect the diversity of the environmental settings across Arkansas. Topics ranged from salt water and critical ground water issues in the Delta to endangered species and interbasin ground-water recharge in …

Geosciences Newsletter - 2000, Department Of Geosciences

Geological and Environmental Sciences News

Vol.1, No. 25

• Greetings All
• Faculty News
• Groundwater Education in Michigan News
• Graduate Student News
• Alumni News
• Advisory Council News

Biogeochemistry And Contaminant Geochemistry Of Marine And Estuarine Sediments, New Haven, Connecticut (Usa), Michael A. Kruge, Gaboury Benoit

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The urbanized shore areas of Long Island Sound in the vicinity of New Haven, Connecticut (USA) have a long history of exposure to point and non-point sources of pollution, New Haven having been one of the birthplaces of the industrial revolution. As an unintended consequence of such activities, the region's sedimentary systems have incorporated a complex mixture of organic and inorganic contaminants. With its long and varied pollution history and the multiplicity of sedimentary environments (fluvial, estuarine, intertidal, marsh, etc.) present in a compact geographical area, the region is ideal natural laboratory for field testing new contamination assessment techniques. The …

Profiting From Adversity - Meeting The Challenge Of Salinity Through New Industry Development, Andrew Quinn, Tamara Law, Peter Rowe

Natural resources published reports

Salinity in the Wheatbelt of Western Australia is one of the most significant challenges facing the State's agricultural sector.

Efforts to manage the increasing effect of salt influenced and threatened farming land requires not only the implementation of new farming systems, but a new way of thinking and attitude to production more in tune with environmental and technological limitations.

While past environment lobby pressures have significantly focused on other production activities such as mining and forestry, the future is likely to see increased community interest in agricultural production systems.

Consumers World wide are becoming more environmentally sensitive, with global media …

Low Recharge Farming Systems. Case Studies On The South Coast, Arjen Ryder, Jamie Bowyer, Gerry Skinner, Clare Mccarron

Natural resources published reports

This booklet is intended as a guide to assist land managers to design or select low recharge farming systems. Options that increase water use are described with benefits and issues for each option.

Case studies describe the experiences of landholders who have had a go at establishing and managing such systems. Examples are included from different rainfall zones. The systems mentioned in this manual are only a guide.

Case studies describe the experiences of landholders who have hada go at establishing and managing such systems. Examples are included from different rainfall zones. The systems mentioned in this manual are only …

Alternative Principal Components Regression Procedures For Dendrohydrologic Reconstructions, Hugo G. Hidalgo, Thomas C. Piechota, John A. Dracup

Civil and Environmental Engineering and Construction Faculty Research

Streamflow reconstruction using tree ring information (dendrohydrology) has traditionally used principal components analysis (PCA) and stepwise regression to form a transfer function. However, PCA has several procedural choices that may result in very different reconstructions. This study assesses the different procedures in PCA-based regression and suggests alternative procedures for selection of variables and principal components. Cross-validation statistics are presented as an alternative for independently testing and identifying the optimal model. The objective is to use these statistics as a measure of the model's performance to find a conceptually acceptable model with a low prediction error and the fewest number of …

Modifications Of The C37 Alkenone And Alkenoate Composition In The Water Column And Sediment: Possible Implications For Sea Surface Temperature Estimates In Paleoceanography, Joan O. Grimalt, Jürgen Rullkötter, Marie-Alexandrine Sicre, Roger Summons, John Farrington, H. Rodger Harvey, Miguel Goñi, Ken Sawada

OES Faculty Publications

The literature pertaining to C37 alkenone and C37 and C38 alkenoate production and diagenesis has been reviewed and evaluated for issues that might jeopardize their usefulness in paleotemperature estimation. We also examined the use of the C37 alkenones as paleoproductivity indicators, the stability of their δ13C isotopic compositions, and their incorporation into the nonsolvent extractable organic matter fraction. Biological transformation of organic matter by bacteria and zooplankton does not appear to cause significant changes to the ratio of C37:2 and C37:3 alkenones, but there are major alterations in the relative composition of alkenoates. Studies of water column processes and postdepositional …

Lava And Ice Interaction At Stratovolcanoes: Use Of Characteristic Features To Determine Past Glacial Extents And Future Volcanic Hazards, David T. Lescinsky, Jonathan H. Fink

Geology Faculty Publications and Presentations

Structures resulting from lava and ice interaction are common at glaciated stratovolcanoes. During summit eruptions at stratovolcanoes, meltwater is produced and travels freely down steep slopes and thin permeable valley glaciers, eroding the ice and enlarging preexisting glacial drainages. As a result, in this environment have produced few catastrophic floods. Lava flowing into the open channels and voids in the glaciers becomes confined and grows thicker, filling the available space and producing steep-sided bodies with smooth, bulbous contact surfaces. Quenching of lava against ice or by water forms small-scale features such as tensional fractures and glass. As the amount of …

Basaltic Lava Domes, Lava Lakes, And Volcanic Segmentation On The Southern East Pacific Rise, Scott M. White, Ken C. Macdonald, Rachel M. Haymon

Faculty Publications

Meter-scale DSL-120 sonar mapping and coregistered Argo II photographic observations reveal changes in eruptive style that closely follow the third-order structural segmentation of the ridge axis on the southern East Pacific Rise, 17^o11'-18^o37'S. Near segment ends we observe abundant basaltic lava domes which average 20 rn in height and 200 rn in basal diameter and have pillow lava as the dominant lava morphology. The ubiquity of pillow lava suggests low effusion rate eruptions. The abundance of lava domes suggests that the fissure eruptions were of sufficient duration to focus and produce a line of volcanic edifices. …

Use Of Goes Thermal Infrared Imagery For Eruption Scale Measurements, Soufrière Hills, Montserrat, William I. Rose, Gari C. Mayberry

Department of Geological and Mining Engineering and Sciences Publications

GOES two-band IR data are used to estimate the magnitude of small eruption clouds (ash; <∼10⁵ tonnes of fine [1–25 µm in diameter] ash, and 5–15 km asl). The method is demonstrated on clouds from Soufrière Hills Volcano, Montserrat in 1997–99. The clouds in early 1999 were much smaller, were generally emplaced lower in the atmosphere and contained an order of magnitude less fine ash than 1997 clouds generated during the most intense phase of the eruption to date. Although GOES has an excellent capability for large eruption clouds, its use for smaller eruptions like Montserrat highlights several shortcomings, including …

Dealing With A Dry Season, Department Of Agriculture And Food, Western Australia

Bulletins 4000 -

Farmers' approaches to adverse seasonal conditions whether they be frost, flood or low rainfall should be to acquire as much information as possible on the immediate agronomic and financial situations and make a judgement on the longer term implications for the following seasons. Once the information has been acquired, in consultation with advisers, it is necessary to construct and implement agronomic and business strategies to deal with individual situations.

The agronomic and stocking options for the dry season supplied in this booklet deal with questions and issues arising from the Year 2000 season, which has been characterised by a mid …

Investigation Of Optimum Sample Number And Timing For Determining Pollution Loads, T. S. Soerens, Marc A. Nelson

Arkansas Water Resources Center Technical Reports

In order to determine the impacts of non point source (NPS) pollution and to develop Total Maximum Daily Loads (Tr\tfDLs), accurate measurements of pollution loads in streams are critical. The objectives of this study were to accurately detemline pollutant loads at two sites by intensive storm sampling, to develop sub-sampling and other data analysis techniques, to detemline the effect of sample interval on load calculation accuracy, and to find the minimum sample interval required to determine storm loads at a required accuracy. The two stream sites used were a 1st order and a 3rd order stream in the Illinois River …

Evolution Of The Kangmar Dome, Southern Tibet: Structural, Petrologic, And Thermochronologic Constraints, Jeffrey Lee, Bradley R. Hacker, William S. Dinklage, Yu Wang, Phillip Gans, Andrew Calvert, Jinglin Wan, Wenji Chen, Ann E. Blythe, William Mcclelland

All Faculty Scholarship for the College of the Sciences

Structural, thermobarometric, and thermochronologic investigations of the Kangmar Dome, southern Tibet, suggest that both extensional and contractional deformational histories are preserved within the dome. The dome is cored by an orthogneiss which is mantled by staurolite + kyanite zone metasedimentary rocks; metamorphic grade dies out up section and is defined by a series of concentric kyanite-in, staurolite-in, garnet-in, and chloritoid-in isograds. Three major deformational events, two older penetrative events and a younger doming event, are preserved. The oldest event, D1, resulted in approximately E-W trending tight to isoclinal folds of bedding with an associated moderately to steeply north dipping axial …

Earth News, Fall 2000, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- From the Department Head
--- Earth Science Staff Activities
--- Earth Science Majors
--- 2000 Earth Science Graduates
--- Earth Science Seminar Series
--- Earth Science Student Assistants
--- Sigma Gamma Epsilon - Gamma Sigma Chapter
--- Gifts to the Department of Earth Science
--- 2000-2001 Scholarship and Award Recipients
--- Earth Science Alumni News
--- 1999-2000 Scholarship and Award Recipients

Catchment Water Management: Guidelines For Those Considering Drainage For Waterlogging And Salinity Management, Department Of Agriculture And Food, Western Australia, Water And Rivers Commission, State Salinity Council

Bulletins 4000 -

Landholder groups and government agencies are continuing to develop "best drainage practice" guidelines and these will increase our knowledge of drainage, and deep drainage in particular, as a management tool. The brochure does not provide all the answers, but is intended to provide some basic information to assist landholders who may be considering some form of water management or drainage systems.

Intensification Of The Northeast Pacific Oxygen Minimum Zone During The Bolling-Allerod Warm Period, Yan Zheng, Alexander Van Green, Robert F. Anderson, James V. Gardner, Walter E. Dean

United States Geological Survey: Staff Publications

Although climate records from several locations around the world show nearly synchronous and abrupt changes, the nature of the inferred teleconnection is still poorly understood. On the basis of preserved laminations and molybdenum enrichments in open margin sediments we demonstrate that the oxygen content of northeast Pacific waters at 800 m depth during the Bolling-Allerod warm period (15-13 kyr) was greatly reduced. Existing oxygen isotopic records of benthic and planktonic foraminifera suggest that this was probably due to suppressed ventilation at higher latitudes of the North Pacific. Comparison with ventilation records for the North Atlantic indicates an antiphased pattern of …

Response Of A First-Order Stream In Maine To Short-Term In-Stream Acidification, S. A. Norton, R. Wagai, T. Navratil, J. M. Kaste, F. A. Rissberger

Dartmouth Scholarship

An experimental short-term acidification with HCl at a first-order stream in central Maine, USA was used to study processes controlling the changes in stream chemistry and to assess the ability of stream substrate to buffer pH. The streambed exerted a strong buffering capacity against pH change by ion exchange during the 6-hour acidification. Streambed substrates had substantial cation and anion exchange capacity in the pH range of 4.1 to 6.5. The ion exchange for cations and SO₄^2- were rapid and reversible. The speed of release of cations from stream substrates was Na¹⁺> Ca²⁺ > Mg²⁺ > Al …