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Articles 16321 - 16350 of 17789
Full-Text Articles in Entire DC Network
Pesticides In Streams Draining Agricultural And Urban Areas In Colorado, Robert Kimbrough, David Litke
Pesticides In Streams Draining Agricultural And Urban Areas In Colorado, Robert Kimbrough, David Litke
United States Geological Survey: Staff Publications
A study was conducted from April 1993 through April 1994 to describe and compare the occurrence and distribution of pesticides in streams in a small agricultural and a small urban area in Colorado. Twenty-five water samples collected at least monthly at the mouths of two tributary streams of the South Platte River were analyzed for 47 pesticides. The results indicate that both agricultural and urban areas are probable sources for pesticides in streams. In the agricultural area, 30 pesticides were detected, and in the urban area, 22 pesticides were detected in one or more samples. Most often, the more frequently …
New Palaeothentid Marsupials (Caenolestoidea) From The Early Miocene Of Patagonian Argentina, Todd C. Rae, Thomas M. Bown, John G. Fleagle
New Palaeothentid Marsupials (Caenolestoidea) From The Early Miocene Of Patagonian Argentina, Todd C. Rae, Thomas M. Bown, John G. Fleagle
United States Geological Survey: Staff Publications
Recent fieldwork in Argentina has resulted in the recovery of numerous new specimens of palaeothentid marsupials, an important component of the Deseadan-Santacrucian (Oligocene-middle Miocene) mammalian fauna of Patagonia. The 1994 collections include a new genus and species from the early Miocene Pinturas Formation at Estancia La Cafnada and the first complete lower dentition of Acdestis oweni from a locality in the Santa Cruz Formation along the Rio Chalia.
Sources Of Variation In Counts Of Meristic Features Of Yellowstone Cutthroat Trout (Oncorhynchus Clarki Bouvieri), Carter Kruse, Wayne Hubert, Frank Rahel
Sources Of Variation In Counts Of Meristic Features Of Yellowstone Cutthroat Trout (Oncorhynchus Clarki Bouvieri), Carter Kruse, Wayne Hubert, Frank Rahel
United States Geological Survey: Staff Publications
We determined variability in counts of meristic features (pyloric caecae, vertebrae, pelvic fin rays, gillrakers, basibranchial teeth, scales above the lateral line, and scales in the lateral series) of Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri ) by 3 independent readers, by the same reader on 3 different occasions, and among fish from 12 sampling sites within a 650-km2 watershed. Genetic purity of the cutthroat trout was determined by electrophoretic analysis. Significant differences in meristic counts were observed among 3 readers and among sampling sites, but not among 3 occasions by a single reader. Scale counts were within the …
Soil Information Sheets For The Mount Beaumont, Mallee And Esperance Agricultural Areas, Department Of Agriculture And Food, Landcare Western Australia, Esperance Land Conservation District Committee, Mount Beaumont / Howick Catchment Group (W.A.)
Soil Information Sheets For The Mount Beaumont, Mallee And Esperance Agricultural Areas, Department Of Agriculture And Food, Landcare Western Australia, Esperance Land Conservation District Committee, Mount Beaumont / Howick Catchment Group (W.A.)
Agriculture reports
Each sheet summarises information on the soil's characteristic properties, and associated land use suitability and management. A photograph of a representative profile is provided for each soil. Technical terms are defined in soil sheet glossary. Information is presented under the following headings: soil series and groups, occurence, native vegetation, soil profile description, characteristic soil properties, soil classification and agricultural land use and management.
Artificial Maturation Of Alginite And Organic Groundmass Separated From Torbanites, Michael A. Kruge, Patrick Landais, David F. Bensley
Artificial Maturation Of Alginite And Organic Groundmass Separated From Torbanites, Michael A. Kruge, Patrick Landais, David F. Bensley
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
The two principal organic constituents — Botryococcus-related alginite and organic groundmass — were isolated by density separation from two torbanite samples (from the Stellarton Fm., Nova Scotia, Canada and the King Cannel, Utah, USA). The groundmass consisted of degraded algal, bacterial and terrestrial plant debris. Aliquots of alginite and groundmass were separately heated in gold tubes for 24 hr. with 70 MPa confining pressure, at fixed temperatures ranging between 250 and 375°C. The 250, 300 and 325°C experiments run on the alginite produced very low yields of CHCl3-extractable organic matter (EOM), indicating that very little of the generation potential …
Organic Geochemistry And Petrology Of Oil Source Rocks, Carpathian Overthrust Region, Southeastern Poland — Implications For Petroleum Generation, Michael A. Kruge, Maria Mastalerz, Andrzej Solecki, B Artur Stankiewicz
Organic Geochemistry And Petrology Of Oil Source Rocks, Carpathian Overthrust Region, Southeastern Poland — Implications For Petroleum Generation, Michael A. Kruge, Maria Mastalerz, Andrzej Solecki, B Artur Stankiewicz
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
The organic matter rich Oligocene Menilite black shales and mudstones are widely distributed in the Carpathian Overthrust region of southeastern Poland and have excellent hydrocarbon generation potential, according to TOC, Rock-Eval, and petrographic data. Extractable organic matter was characterized by an equable distribution of steranes by carbon number, by varying amounts of 28,30-dinor-hopane, 18α(H)-oleanane and by a distinctive group of C24 ring-A degraded triterpanes. The Menilite samples ranged in maturity from pre-generative to mid-oil window levels, with the most mature in the southeastern portion of the study area. Carpathian petroleum samples from Campanian-Oligocene sandstone reservoirs were similar …
Evaluation Of The Crop Growth Component Of The Root Zone Water Quality Model For Corn In Ohio, Sue E. Nokes, Feliks M. Landa, Jon D. Hanson
Evaluation Of The Crop Growth Component Of The Root Zone Water Quality Model For Corn In Ohio, Sue E. Nokes, Feliks M. Landa, Jon D. Hanson
Biosystems and Agricultural Engineering Faculty Publications
The Root Zone Water Quality Model (RZWQM) is a computer model developed to simulate water, chemical, and biological processes in the root zone of agricultural management systems. As of this writing RZWQM is in the beta-testing phase of development. This article reports on a parameterization and evaluation study performed in Ohio on field corn for the crop growth component of RZWQM. The generic crop growth model in RZWQM had not previously been parameterized or tested on field corn. This article reports the results of such a study. One year of data was used to calibrate RZWQM, and two additional years …
Comparison Of Daily Water Table Depth Prediction By Four Simulation Models, Eric D. Desmond, Andrew D. Ward, Norman R. Fausey, Stephen R. Workman
Comparison Of Daily Water Table Depth Prediction By Four Simulation Models, Eric D. Desmond, Andrew D. Ward, Norman R. Fausey, Stephen R. Workman
Biosystems and Agricultural Engineering Faculty Publications
The Agricultural Drainage And Pesticide Transport (ADAPT) model was compared to the water management simulation models DRAINMOD, SWATREN, and PREFLO. SWATREN and PREFLO are one-dimensional finite-difference models while ADAPT and DRAINMOD are one-dimensional mass balance models. ADAPT, an extension of the computer model GLEAMS, also provides chemical transport information. All four models were tested against field data from Aurora, North Carolina. Observed water table depth data were collected during 1973 through 1977 from a water table management field experiment with three subsurface drain spacing treatments of 7.5, 15, and 30 m.
Both the standard error of estimate and the average …
Performance Of Vegetative Filter Strips With Varying Pollutant Source And Filter Strip Lengths, Puneet Srivastava, Dwayne R. Edwards, Tommy C. Daniel, Philip A. Moore Jr., Thomas A. Costello
Performance Of Vegetative Filter Strips With Varying Pollutant Source And Filter Strip Lengths, Puneet Srivastava, Dwayne R. Edwards, Tommy C. Daniel, Philip A. Moore Jr., Thomas A. Costello
Biosystems and Agricultural Engineering Faculty Publications
Vegetative filter strips (VFS) can reduce runoff losses of pollutants such as nitrogen (N) and phosphorus (P) from land areas treated with fertilizers. While VFS effectiveness is considered to depend on lengths of pollutant source and VFS areas, there is little experimental evidence of this dependence, particularly when the pollutant source is manure-treated pasture. This study assessed the effects of pollutant source area (fescue pasture treated with poultry litter) length and VFS (fescue pasture) length on VFS removal of nitrate N (NO3-N), ammonia N (NH3-N), total Kjeldahl N (TKN), ortho-P (PO4-P), total P (TP), …
Soil Information Sheets For Part Of The Jerramungup Agricultural Area, Tim D. Overheu, Landcare Western Australia, Jerramungup Land Conservation District Committee
Soil Information Sheets For Part Of The Jerramungup Agricultural Area, Tim D. Overheu, Landcare Western Australia, Jerramungup Land Conservation District Committee
Agriculture reports
Each sheet summarises information on the soil's characteristic properties, and associated land use suitability and management. A photograph of a representative profile is provided for each soil. Technical terms are defined in soil sheet glossary. Information is presented under the following headings: soil series and groups, occurence, native vegetation, soil profile description, characteristic soil properties, soil classification and agricultural land use and management.
Hydrogeology, Hydrogeochemistry, And Spoil Settlement At A Large Mine-Spoil Area In Eastern Kentucky: Star Fire Tract, David R. Wunsch, James S. Dinger, Page B. Taylor, Daniel I. Carey, C. Douglas R. Graham
Hydrogeology, Hydrogeochemistry, And Spoil Settlement At A Large Mine-Spoil Area In Eastern Kentucky: Star Fire Tract, David R. Wunsch, James S. Dinger, Page B. Taylor, Daniel I. Carey, C. Douglas R. Graham
Report of Investigations--KGS
An applied research program at the Star Fire surface mine in eastern Kentucky, owned and operated by Cypress-AMAX Coal Co., defined spoil characteristics to develop and monitor water resources, which will help identify a reliable water supply for future property development. Water stored in the mine spoil may provide a usable ground-water supply, and the spoil could also be engineered to provide base flow to surfacewater reservoirs.
Ground-water recharge enters the spoil by way of sinking streams, ground-water flow from bedrock in contact with the mine spoil, and a specially designed infiltration basin. Ground water discharges predominantly from springs and …
Observations On Bats At Badlands National Park, South Dakota, Michael A. Bogan, Jeffrey G. Osborne, Jennifer A. Clarke
Observations On Bats At Badlands National Park, South Dakota, Michael A. Bogan, Jeffrey G. Osborne, Jennifer A. Clarke
United States Geological Survey: Staff Publications
During the summers of 1992 and 1993, we conducted a survey of bats at Badlands National Park, South Dakota. Using mist nets, we captured bats and recorded species, sex, age class, and reproductive condition for each individual netted. We recorded five species, Myotis ciliolabrnm (n = 198), M. thysanodes (29), M volans (13), Eptesicus foscus (91), and Plecotus tawnsendii (43), previously known from the park. In addition, we added four species, M lucifugus (18), M. septentrionalis (9), Lasionycteris noctivagans (1), and Lasiurns cinereus (3) to the confirmed fauna of the park. Most bats captured were male (76.3%) although maternity colonies …
Origin Of Bermuda's Clay-Rich Quaternary Paleosols And Their Paleoclimatic Significance, Stanley R. Herwitz, Daniel R. Muhs, Joseph M. Prospero, Shannon Mahan, Bruce Vaughn
Origin Of Bermuda's Clay-Rich Quaternary Paleosols And Their Paleoclimatic Significance, Stanley R. Herwitz, Daniel R. Muhs, Joseph M. Prospero, Shannon Mahan, Bruce Vaughn
United States Geological Survey: Staff Publications
Saharan dust deposition on Bermuda during successive Quaternary glacial periods is consistent with patterns of general circulation models, which indicate that during glacial maxima the northeast summer trade winds were stronger than at present and reached latitudes higher than 30°N despite lower-than-present sea surface temperatures in the North Atlantic.
Domestic Well-Water Quality In Rural Nebraska, D. C. Gosselin, J. Headrick, X. H. Chen, S. Summerside, R. Tremblay, K. Bottger
Domestic Well-Water Quality In Rural Nebraska, D. C. Gosselin, J. Headrick, X. H. Chen, S. Summerside, R. Tremblay, K. Bottger
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Reference Sediment Selection In The Lower Mississippi Delta, M. T. Moore, C. D. Milam, Jerry L. Farris
Reference Sediment Selection In The Lower Mississippi Delta, M. T. Moore, C. D. Milam, Jerry L. Farris
Journal of the Arkansas Academy of Science
Floodplain deposition has been a critical part in the evolution of Arkansas' Delta ecoregion, and because ofits high potential for such events, this region is highly enriched and extremely fertile. Historically, water quality in the area has been the subject ofscientific study, and as a result littlehas been published on the effects of underlying sediment with associated benthic communities. Sediment analysis is critical to many of the ongoing aquatic studies because ofits significance as both a habitat for benthic organisms and a sink for contaminants. Seven rivers and one creek within the Delta ecoregion were examined for water chemistry, sediment …
Temporal And Spatial Patterns In Water Chemistry, Phytoplankton Biomass And Microcrustacea In Lake Joondalup And Beenyup Swamp, Western Australia, Kimberley Upton
Temporal And Spatial Patterns In Water Chemistry, Phytoplankton Biomass And Microcrustacea In Lake Joondalup And Beenyup Swamp, Western Australia, Kimberley Upton
Theses : Honours
Lake Joondalup is one of the largest remaining permanent lakes of the Swan Coastal Plain. Despite increasing urbanisation, it supports highly diverse terrestrial and riparian communities, and an abundant and diverse aquatic fauna. However, like other wetlands of the Swan Coastal Plain, Lake Joondalup is increasingly threatened by eutrophication and degradation. The aims of this study were to describe the patterns in selected physical, chemical parameters, microcrustacean abundance and biomass of Daphnia carinata in Beenyup Swamp and the adjacent sections of Lake Joondalup; to identify the likely factors determining the patterns of phytoplankton biomass in these wetlands; and to suggest …
Quality Of Runoff From Four Northwest Arkansas Pasture Fields Treated With Organic And Inorganic Fertilizer, Dwayne R. Edwards, Tommy C. Daniel, John F. Murdoch, Philip A. Moore Jr.
Quality Of Runoff From Four Northwest Arkansas Pasture Fields Treated With Organic And Inorganic Fertilizer, Dwayne R. Edwards, Tommy C. Daniel, John F. Murdoch, Philip A. Moore Jr.
Biosystems and Agricultural Engineering Faculty Publications
Long-term land application of animal manures, even at agronomic rates, can promote accumulation of soil phosphorus (P) which can, in turn, contribute to increased P loadings to downstream waters. The objective of this study was to assess the soil and runoff effects of replacing animal manure as a soil amendment with inorganic fertilizer (ammonium nitrate, NH4NO3) on fields that had been treated previously with animal manures. Runoff from two pairs of small fields (0.57 to 1.46 ha) was sampled from September 1991 to April 1994. All fields had been treated previously with animal manures; after runoff …
Poultry Litter-Treated Length Effects On Quality Of Runoff From Fescue Plots, Dwayne R. Edwards, Philip A. Moore Jr., Tommy C. Daniel, Puneet Srivastava
Poultry Litter-Treated Length Effects On Quality Of Runoff From Fescue Plots, Dwayne R. Edwards, Philip A. Moore Jr., Tommy C. Daniel, Puneet Srivastava
Biosystems and Agricultural Engineering Faculty Publications
Using experimental data and/or mathematical simulation models to identify practices that reduce pollution from manure-treated areas is sometimes perceived as limited by the unknown validity of extrapolating plot-scale data to larger areas and by uncertainties in modeling transport of various pollutants. The objectives of this study were to assess the effect of length of manure treatment on runoff concentrations of poultry litter constituents and to define the modes of transport (particulate versus soluble) for nitrogen (N), phosphorus (P), carbon (C), and solids. Poultry litter was applied to three 1.5- x 18.3-m fescue (Festuca arundinacea Schreb.) plots with runoff collection …
Application Of Simplified Phosphorus Transport Models To Pasture Fields In Northwest Arkansas, Dwayne R. Edwards, C. T. Haan, Andrew N. Sharpley, John F. Murdoch, Tommy C. Daniel, Philip A. Moore Jr.
Application Of Simplified Phosphorus Transport Models To Pasture Fields In Northwest Arkansas, Dwayne R. Edwards, C. T. Haan, Andrew N. Sharpley, John F. Murdoch, Tommy C. Daniel, Philip A. Moore Jr.
Biosystems and Agricultural Engineering Faculty Publications
Runoff transport of phosphorus (P) is often predicted from simple equations with parameters determined from data applicable primarily to row-cropped and fallow cover conditions. The applicability, accuracy, and precision of such P transport prediction equations under pasture situations are less well defined. The objectives of this study were to determine parameters of simplified runoff P transport equations for pasture fields and to assess the accuracy and precision of the equations. Runoff, sediment yield, soluble P transport, and particulate P transport data were collected from four pasture fields in northwestern Arkansas. Runoff event enrichment ratios and extraction coefficients were computed, and …
Hydrologic Factors Affecting The Discharge Of Ground Water In The Red River Of The North Basin, Northeastern North Dakota, Michael Lee Strobel
Hydrologic Factors Affecting The Discharge Of Ground Water In The Red River Of The North Basin, Northeastern North Dakota, Michael Lee Strobel
Theses and Dissertations
Ground-water discharge from bedrock aquifers contributes significant amounts of salinity to the Red River of the North. The area of major discharge is represented on the land surface by saline soils, wetlands, and flowing wells. As tributaries flow through these areas, the dissolved-solids concentrations in the streams increase. This salinity is then transported to the Red River of the North and northward to Canada. The bedrock units that supply the saline water are mainly the Dakota Group. Overlying the bedrock are sediments from numerous glacial advances and lacustrine sediments from glacial Lake Agassiz. These units form confining layers over the …
Glacial Deposits, Vol. 24, 1995-1996, Department Of Geography-Geology
Glacial Deposits, Vol. 24, 1995-1996, Department Of Geography-Geology
Glacial Deposits
Newsletter of the Department of Geography-Geology
Factors Affecting Attwater's Prairie-Chicken Decline On The Attwater Prairie Chicken, Michael E. Morrow, Robert S. Adamcik, Jenny D. Friday, Lloyd B. Mckinney
Factors Affecting Attwater's Prairie-Chicken Decline On The Attwater Prairie Chicken, Michael E. Morrow, Robert S. Adamcik, Jenny D. Friday, Lloyd B. Mckinney
United States Geological Survey: Staff Publications
We examined the association between changes in the number of Attwater's prairie-chicken (Tympanuchus cupido attwateri) on the Attwater Prairie Chicken National Wildlife Refuge from 1972 to 1993 and changes in refuge management practices (burning and grazing). We also examined the relationship of prairie-chicken population increases and decreases on the refuge to rainfall and off-refuge prairie-chicken populations. Burning within the prairie-chicken's core habitat on the refuge and variability in grassland structure were directly correlated (P < 0.05) with increases and declines in prairie-chicken populations. Refuge population increases and declines were inversely correlated (P < 0.1) with average April rainfall/event, May absolute departure from long-term average rainfall, May number of rainfall events, annual absolute departure of rainfall from the long-term average, and the annual number of rainfall events. Refuge population increases and declines were directly correlated (P < 0.1) with off-refuge populations, although the off- refuge population decline began 4 years earlier than on-refuge.
Late Pliocene Diatoms In A Diatomite From Prydz Bay, East Antarctica, Albert D. Mahood, John A. Barron
Late Pliocene Diatoms In A Diatomite From Prydz Bay, East Antarctica, Albert D. Mahood, John A. Barron
United States Geological Survey: Staff Publications
Very well-preserved Pliocene diatoms from a diatomite unit interbedded within glacial sediments at Ocean Drilling Program Site 742 in Prydz Bay, Antarctica are documented and illustrated. The presence of Thalassiosira kolbei, T torokina, Actinocyclus actinochilus, A karstenii and the absence of Nitzschia interfrigidaria, T. insigna and T. vulnifica in Sample 119-742A-15R-4, 44-46 cm constrain its age to ca. 2.2-1.8 Ma (late Pliocene). Diatoms associated with sea ice constitute 35% of the Pliocene diatom assemblage, compared with 71% of the modern sediment assemblage at the site, suggesting that sea ice was present during the late Pliocene period of deposition of the …
A Functional Group Approach To Detecting Shifts In Macroalgal Communities Along A Disturbance Gradient, J. C. Phillips
A Functional Group Approach To Detecting Shifts In Macroalgal Communities Along A Disturbance Gradient, J. C. Phillips
Theses : Honours
A recently proposed hypothesis argued that morphologically and functionally similar macroalgae could be grouped to study the structure of macroalgal communities. It was argued that these functional groups can be used to predict changes to community composition that result from disturbance. This study examined whether the functional group model held in detecting changes in macroalgal community structure within one bioregion, by applying it to a habitat exposed to different levels of physical disturbance associated with wave exposure. Results obtained using a functional group approach were compared to those obtained using a species level approach. Three parallel reef lines in Marmion …
The Effects Of Mass Extinction On Escalation Of The Naticid Gastropod Predator-Prey System At The Eocene-Oligocene, Vicky D. Melland
The Effects Of Mass Extinction On Escalation Of The Naticid Gastropod Predator-Prey System At The Eocene-Oligocene, Vicky D. Melland
Theses and Dissertations
In 1987, Vermeij proposed the hypothesis of escalation, which states that biological hazards, such as predation, have increased through the Phanerozoic. This hypothesis has been extremely controversial due to the fact that it assumes that biotic factors, such as predation, have had an important role in evolution. Several studies have focused on the validity of the hypothesis of escalation. Kelley and Hansen (1996) offered a modified exposition of the escalation hypothesis. The Kelley-Hansen hypothesis states that escalation cycles are punctuated by periods of mass extinction. The periods of mass extinction would preferentially eliminate the highly escalated prey and, therefore, a …
Synthetic Organic Compounds: Las Vegas Wash And Lake Mead, National Water Quality Assessment Program (Nawqa): Nevada Basin And Range
Synthetic Organic Compounds: Las Vegas Wash And Lake Mead, National Water Quality Assessment Program (Nawqa): Nevada Basin And Range
Publications (WR)
The Nevada Basin and Range (NVBR) study unit of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program is investigating the status of, trends in, and factors affecting water quality in the Las Vegas area. A principal objective of the investigation is to assess the effects of urbanization on the quality of area water resources. Las Vegas Wash is the surface-water outlet for the Las Vegas area. The wash transports stormwater runoff, shallow ground-water discharge, and tertiary-treated sewage effluent from the Las Vegas area to Las Vegas Bay of Lake Mead on the Colorado River. Most of the flow—about 96 …
A Recent Colonization Of Dolichopoda Cave Crickets In The Poscola Cave (Orthoptera, Rhaphidophoridae), Camilla Bernardini, Claudio Di Russo, Mauro Rampini, Donatella Cersaroni, Valerio Sbordoni
A Recent Colonization Of Dolichopoda Cave Crickets In The Poscola Cave (Orthoptera, Rhaphidophoridae), Camilla Bernardini, Claudio Di Russo, Mauro Rampini, Donatella Cersaroni, Valerio Sbordoni
International Journal of Speleology
We report a series of investigations carried out on a Dolichopoda population recently discovered in the Poscola cave and in some small caves nearby (Lessini Mountains, Vicenza). This population is located north of Po river, outside the present known geographic range of this genus in Italy. Morphology of the epiphallus corroborated by chromosome and allozyme analysis indicated that this population belongs to D. laetitiae. Study of the genetic structure of population in the Poscola area revealed high gene flow levels between Poscola and the other minor caves, suggesting the occurrence of a single expanding population. This finding as well …
Geographical Variation In The Tropical Cave Cockroach Paratemnopteryx Stonei Roth (Blattellidae) In North Queensland, Australia, David Paul Slaney, Philip Weinstein
Geographical Variation In The Tropical Cave Cockroach Paratemnopteryx Stonei Roth (Blattellidae) In North Queensland, Australia, David Paul Slaney, Philip Weinstein
International Journal of Speleology
Observations of cave dwelling organisms in both tropical and temperate caves often reveal morphological modifications, which may reflect various stages of adaptation to cave life. From April 1994 to June 1995 a number of adult Paratemnopteryx stonei were collected from 7 caves in tropical North Queensland to investigate the degree of geographical variation in such troglomorphies between cave populations. Results of morphometric analyses showed the occurrence of a morphological discontinuity between cave populations from the different geographic regions. The body dimensions particularly important in discriminating between each cave population were tegmen length (both sexes), and secondly, tegmen width and tarsus …
Weathering Crust And Karren On Exposed Gypsum Surfaces, Tommaso Macaluso, Ugo Sauro
Weathering Crust And Karren On Exposed Gypsum Surfaces, Tommaso Macaluso, Ugo Sauro
International Journal of Speleology
The evolution of gypsum bare rock surfaces is the result both of volume changes of the outer rock layer and mass wasting by dissolutional processes. Some unusual weathering processes induce an increase in the volume of the outer gypsum layer, resulting in the development of a “weathering crust” and of characteristic forms such as small ridges and bubbles. However, the more typical erosional forms are dissolutional ones of karren type, which are commonly interconnected, or superimposed upon the previously described forms. In this chapter a classification system is proposed and discussed, within which the magnitude, order and geometry of the …
Gypsum Karst Of The World: A Brief Overview, Alexander Klimchouk, Paolo Forti, Anthony Cooper
Gypsum Karst Of The World: A Brief Overview, Alexander Klimchouk, Paolo Forti, Anthony Cooper
International Journal of Speleology
Short description of caves and karsts in gypsum of different parts of the World.