bluuebunny/crossref_metadata_2025_split huggingface dataset:
Archaeological geology of the Rustad Quarry site (32RI775): An early archaic site in Southeastern North Dakota
Authors: Running Garry Leonard 
Published: February 2007

AbstractAt The Rustad Quarry Site (32RI775), in southeastern North Dakota, Early Archaic artifacts, bison bone, and hearth features were found in the lowest of three Boroll‐like buried soils formed in alluvial fan sediments. Alluvial fan sediments were deposited from 8000 to 4925 B.P., and were then buried by eolian sand. The alluvial fan sediments (mudflows) bury lacustrine sediments (Sherack Formation deposited from 9900 to 9500 B.P. in Glacial Lake Agassiz II), both of which overlie a Moorhead Phase fluvial terrace deposited from 10,900 to 9,900 B.P. Cultural remains were associated with five radiocarbon ages, three on archaeological charcoal (7180 B.P., 7240 B.P., and 7550 B.P.) and two on organic carbon from two welded A‐horizons containing the cultural remains (7370 B.P. and 7675 B.P.). A well‐developed Aquoll‐like soil formed in the lacustrine sediments from 9500 to 8000 B.P. Soil morphology and chemistry of the Boroll‐like fan soils, the Aquoll‐like lacustrine soil, and other Boroll‐like soils formed in eolian and deltaic sediments nearby suggest a subhumid, cool continental climate with riparian woodland and mixed prairie vegetation at the site and surrounding area from 11,400 B.P. to the present. This partially contradicts paleoenvironmental reconstruction from pollen sites nearby that suggest the area was covered by a closed canopy spruce forest from terminal late‐Pleistocene to 10,000 B.P. Alluvial fan formation and eolian activity on the adjacent Sheyenne Delta occurred from 8000 to 5000 B.P., which indicates greater landscape instability and drier conditions during the mid‐Holocene (Altithermal).
Quantifying microartifacts using a personal computer
Authors: Sherwood Sarah C. , Ousley Stephen D. 
Published: February 2007

AbstractMicroartifact analysis is a worthwhile endeavor in archaeological research. A recurring problem, however, has been the time invested in sample quantification. In this paper we offer an interactive way to quantify microartifact samples using a computer program called MMCOUNT. When the technique is applied during the point counting process, the time required to acquire reliable proportions of material classes can be reduced to approximately 25 minutes per sample, significantly less than usual counting times reported in other studies.
Quaternary geology of the upper sabinal River Valley, Uvalde and Bandera counties, Texas
Authors: Mear Charles E. 
Published: February 2007

AbstractControlled by a local base level of downfaulted Edwards and Comanche Peak limestone, and aided by landsliding in Glen Rose marl, the Sabinal River and its tributaries have developed a large valley in the Edwards Plateau. Extensive soil‐covered pediments that cut Glen Rose bedrock and Pleistocene terrace gravels are present along each side of the valley. Six alluvial deposits of late Pleistocene and Holocene age were recognized in the upper Sabinal River valley. The Holocene series is represented by three deposits. The oldest of these exhibits a Stage II calcic horizon and appears to have been deposited before ca. 5000 yr B.P. The Pleistocene deposits have a calcrete zone (calcic Stage IV and III horizon) in the upper 3‐4 m. The Holocene alluviums, locally beveled by stream action, parallel the river's course and contain Archaic and younger artifacts, which in central Texas range in age from about 8000‐350 yr B.P. One of the Holocene deposits (Q2) is correlated with the Georgetown and Fort Hood alluviums of the Cowhouse Creek at Fort Hood, which range in age from 11,000 yr B.P. to 5200 yr B.P., with the Wilson‐Leonard terrace site in the Lampasas Cut Plain that ranges from about 11,000 to 5000 yr B.P., and with Unit E of Blum and Valastro (1989) in the Pedernales River valley, ranging from 10,550 to 7150 yr B.P. Modern climate in the valley is drought‐prone, and fluctuates from semiarid to dry subhumid. Paleoclimate has ranged from much drier during the Middle Holocene to much cooler and wetter during the Late Pleistocene.
Die Bestimmung der Sedimentaktivität Eine Methode zur Abschätzung der organischen Substanz im Benthos durch Messung der Sauerstoffzehrung
Authors: Caspers Hubert 
Published: February 2007

AbstractDie beschriebene Methode ermöglicht, die aktuelle biologische Aktivität des Sedimentes festzustellen, indem die O2‐Zehrung von 10 ml frischem Gewässerboden in 11 Wasser nach 48 Stunden gemessen wird.
Vorschläge für eine saprobiologische Typisierung der Gewässer
Authors: Caspers Hubert , Karbe Ludwig 
Published: February 2007

AbstractSaprobität ist im Rahmen der Bioaktivität des Gewässers die Summe aller der Primärproduktion gegenüberstehenden Umsatzprozesse, also der mit einem Verlust an potentieller Energie verknüpften Vorgänge.Aus ihr ergibt sich in Kombination mit dem biogenen und physikalischen Sauerstoffeintrag der Saprobitätsgrad des Gewässers. Dieser kann sowohl durch stoffwechseldynamische Messungen wie durch die Analyse der Lebensgemeinschaften ermittelt werden.
Comparative Ecology of the Crayfishes Orconectes rusticus rusticus and Cambarus tenebrosus in Doe Run, Meade County, Kentucky
Authors: Prins Rudolph 
Published: February 2007

AbstractThe ecology and life histories of Orconectes rusticus rusticus (GIRARD) and Cambarus tenebrosus HAY were investigated in a spring stream, Doe Run, Meade County, Kentucky, from September 1962 through September 1964. Differences in ecology of these species were most clearly seen in their habitat preferences and distributions in the stream, their feeding habits, responses to temperature, and infestations by an harpacticoid copepod Attheyella carolinensis CHAPPUIS, and in other life history phenomena, particularly with regard to reproduction and growth.Cambarus tenebrosus was most abundant in the constant temperature areas of the headwaters of Doe Run. Orconectes r. rusticus was found only in the lower three‐fourths of the stream. Water temperatures in the headwater area may have been too low (12 — 14 C) for optimal growth of the crayfish had it existed there. Adults of C. tenebrosus were primarily hypogean, but young and subadults frequented the open stream environment. Orconectes r. rusticus was primarily an open stream inhabitant, and was sympatric with C. tenebrosus subadults and young in the downstream areas. When C. tenebrosus occurred in the open environment, it was most abundant in association with vegetation, and hence, was more heavily infested with A. carolinensis than O. r. rusticus.Detritus, mainly from fallen leaves and marl grazings, apparently formed the most important component of the diet of O. r. rusticus. Vascular plants, mainly fallen leaves from the riparian vegetation, constituted the main portion of the diet of C. tenebrosus; filamentous algae were widely used where and when they were present.Orconectes r. rusticus eggs hatch in May. These hatchlings become mature in 15 months and females oviposit after 22 – 24 months from March —May. Sexual maturity is attained at a carapace length of about 18 mm; maximum size is 45 mm. Most animals die after about 2.5 years; however, some live for three years. Molting activity ceases in winter.Cambarus tenebrosus young hatch in July and August. Most hatchlings remain in the burrows until October and November at which time they emerge in response to dominance behavior. Growth occurs throughout the winter months, and sexual maturity is attained in 20 – 22 months when the crayfish are about 40 mm in carapace length. Mature females oviposit during June and July after about 22–23 months, and probably again after 34–35 months. Mating occurs during the winter and spring. In Doe Run, maximum size attained is 65 mm carapace length. Cambarus tenebrosus probably lives for 36 – 38 months.
Limnological Aspects of Some Moroccon Atlas Lakes, with Reference to Some Physical and Chemical Variables, the Nature and Distribution of the Phyto‐ and Zooplankton, Including a Note on Possibilities for the Development of an Inland Fishery
Authors: Dumont Henri J. , Miron Ionel , Dali'asta Ugo , Decraemer Wilfrida , Glaus Christine , Somers Daniel , Dumont Henri J. 
Published: February 2007

AbstractFour mountain lakes were studied. Two are eutrophic, one is mesotrophic and one is oligotrophic. The first three have a well‐developed phyto‐ and zooplankton, with a relatively high diversity index. There are differences between the faunas that may be ascribed to differences in surface, depth, altitude and also to biological phenomena such as interspecies competition. The Ifni Lake is a genuine high‐mountain lake, subject to severe environmental conditions. It has a very simple food chain: there is only one species of algae, an unicellular blue‐green, one copepod species, one rotifer and one fish. In general some features of a definite interest for fundamental limnology were found: the presence of a pelagic Rhabdocoelid in Dayat Ifrah, some particularities in the vertical distribution of a number of plankton species, the existence of a layer of relatively warm water near the bottom of Lake Ifni. The latter is explained by a strong bottom current which flows through the lake between its phreatic in‐ and outlets.Finally, stress is laid on the under‐exploitment of Moroccon inland waters with respect to a freshwater fishery.Yet, perspectives are good and some suggestions are forwarded.
Calamoecia lucasi (Copepoda, Calanoida) and other Zooplankters in Two Rotorua, New Zealand, Lakes
Authors: Chapman M. Ann 
Published: February 2007

AbstractThe seasonal cycles of the zooplankton in 1967–1969 in Lakes Rotorua and Rotoiti in the North Island of New Zealand are outlined. Bosmina meridionalis had several peaks in abundance during the summer and low winter numbers, whilst Ceriodaphnia dubia generally had only a single period of real abundance during the summer. The rotifer Asplanchna priodonta was present throughout the year in low numbers except for two brief but striking peaks in the spring‐summer period. The only cyclopoid copepod present was Macrocyclops albidus which was never abundant.The annual cycles of the calanoid copepod Calamoecia lucasi were studied in some detail. Total numbers were high but very variable during spring‐autumn and low in winter, the seasonal cycles being very similar in both lakes. Breeding was continuous although egg clutches were small (1.1–6.6), and the development of at least 5 cohorts per year could be followed from data on breeding intensity, population age‐structure and adult size. Laboratory determined egg development rates were used to calculate birth rates in the populations so that production and losses could be estimated. Survival rates appeared to be higher in Rotoiti than in Rotorua. Birth and death rates were low, the annual means for both linear and exponential rates ranging from around 0.04 to 0.07, giving turnover times for individuals of 12–18 days in Rotorua and 18–24 days in Rotoiti. Population turnover rates were higher in Rotorua (19–28 days), which had a similar mean population per square metre but higher clutch sizes, than in Rotoiti (18 days).
Composition and Calcium Binding Properties of the Water Soluble Polysaccharides in the Calcareous Alga Halimeda opuntia (L) (Chlorophyta, Udoteaceae)
Authors: Böhm Erich Lothar 
Published: February 2007

AbstractThe mucilages of this alga contain acid polysaccharides, some of which are Ca binding. After deproteinization and gel filtration the residue of the aqueous algal extract has the composition: 2% complexed protein, 3–4% Ca, 0.4–0.5% SiO2, 0.03–0.04% Al, ∼ 0.005% Fe, rest: polysaccharide. The molecular weights of the major and minor polysaccharide fractions are approximately 5000 and 200000 respectively (Sephadex). Uronic acid and O‐ester sulfate give a total of 0.25 μequiv. H+/mg polysaccharide whereas the Ca binding capacity is 2.1 μequiv./mg polysaccharide. Ca complexing of the dibasic polyacid is restricted to the low molecular species and involves the 2 acidic and unidentified nonacidic groups. The complexing strength of the polysaccharide for Ca is similar to succinate. These Ca binding polysaccharides may play a role in algal calcification.
Comparative Morphology and Biology of Three Species of Eurycercus (Chydoridae, Cladocera) with a Description of Eurycercus macrocanthus sp. nov.
Authors: Frey David G. 
Published: February 2007

AbstractComparative studies of the three known species of Eurycercus (including the new species macrocanthus from Eastern Siberia described herein) demonstrate that macrocanthus is much more closely related to lamellatus than to glacialis in many details of morphology, ontogeny, and biology. Its most distinctive character is a great enlargement of the middle clasping hook on the first trunk limb, with the front end of the animal being completely restructured to accomodate its function. Both macrocanthus and lamellatus become reproductive at a small size and have a high reproductive potential, enabling them to survive heavy predation, as by fish, selective for large individuals, which the size‐frequency distributions of the populations suggest is occurring. On the other hand, glacialis does not become reproductive until a much larger size, and its reproductive potential is smaller than in the other species, making it extremely vulnerable to predation concentrated on large individuals. Significantly, where it occurs in the coastal North Sea region, Iceland, and Greenland it is virtually restricted to water bodies without fish. The taxon lamellatus sens. lat. appears to be a complex of closely related species.
Benthic Community Metabolism on the Continental Terrace and in the Deep Sea in the North Pacific
Authors: Pamatmat Mario M. 
Published: February 2007

AbstractThe rates of total oxygen uptake, residual oxygen consumption after poisoning with formaldehyde, and respiration of undisturbed sediment cores from the continental terrace, the abyssal plains, and Aleutian Trench of the North Pacific were measured aboard ship. These measurements, together with determinations of organic carbon, sand, silt, and clay content, of concentrations of reduced substances, and of dissolved oxygen and nutrient salts in interstitial and overlying bottom water, give indications of the level of community metabolism, both aerobic and anaerobic, in the different study areas.
Polychaetes of Truncated Reef Limestone Substrates on Eastern Indian Ocean Coral Reefs: Diversity, Abundance, and Taxonomy
Authors: Kohn Alan J. , Lloyd Margaret C. 
Published: February 2007

AbstractThis study provides the first evaluation of abundance and diversity of polychaete annelid assemblages of coral reefs. Quantitative analyses of the polychaete fauna of truncated coral reef limestone platforms off Sumatra and Thailand revealed a total of 76 species (13 reported for the first time from the tropical Indian Ocean) and average population densities of 49,000/m2. The number of species in a single sample ranged from 16 to 32, and species diversity (H) ranged from 1.9 to 2.5. Three species of Syllidae, Palola siciliensis, and Dodecaceria laddi occurred in all samples. The syllids dominated numerically in all samples but were quite small, mainly 2–10 mm long and 0.01–0.04 mg dry weight. Samples from the same station were essentially identical in species composition and relative abundance. Similarity decreased with increasing distance between stations. With respect to number of species, population density, and dominance of syllids, the assemblages studied resemble those associated with limestone substrates in marine caves in the Mediterranean.
Chlorophyll and Primary Productivity of Some Green, Freshwater Sponges
Authors: Gilbert John J. , Allen Harold L. 
Published: February 2007

AbstractRelationships between ash‐free dry weight, viable chlorophyll a and pheopigments a were examined by linear regression analysis for non‐gemmulating and gemmulated Spongilla lacustris and for an unidentified, non‐gemmulating species. The primary productivity of S. lacustris was determined by both oxygen and 14C techniques and expressed on a biomass, chlorophyll a, and area basis, and the photosynthetic efficiency was calculated. The proportion of algal photosynthate excreted by the sponge was investigated, and the transfer of algal photosynthate to the sponge was examined by autoradiography.
Some Observations on the Chlorophyll Maximum and Primary Production in the Eastern North Pacific
Authors: Revelante Noelia , Gilmartin Malvern 
Published: February 2007

AbstractAn oceanographic transect between Central California and the Hawaiian Islands delimited a continuous subsurface chlorophyll maximum associated with an oxygen maximum at 1% to 0.1% light penetration depths. The phytoplankton community consisted primarily of nannoplankton with a prominent diatom component, and was photosynthetically active as measured in „low light level”︁ incubators, contributing an estimated 20–30% to total water column production. Functioning as a nutrient trap blocking the vertical movement of nutrients into the upper euphotic zone, the chlorophyll maximum apparently required an overlying pycnocline for development.
Methods for Measuring the Primary Productivity and Standing Crops of an Epiphytic Algal Community Attached to Scirpus validus VAHL
Authors: Hickman Michael , Klarer David M. 
Published: February 2007

AbstractMethods for measuring the primary productivity and the standing crops of an epiphytic algal community attached to Scirpus validus VAHL. are described. Experimental designs to show the accuracy of these methods are discussed and the components of variation are calculated for these designs. Primary productivity is measured using the carbon‐14 technique and liquid scintillation counting while the standing crops are measured using cell counts and chlorophyll a content.
Plankton Studies in a Mangrove Environment. VIII. Further Investigations on Primary Production, Standing‐Stock of Phyto‐ and Zooplankton and Some Environmental Factors
Authors: Tundisi J. , Tundisi T. M. , Kutner Myriam B. 
Published: February 2007

AbstractThe present paper describes and discusses the seasonal cycle of primary production, standing‐stock, climatological and environmental factors, and their interrelationships in a mangrove swamp of the estuarine type (25°S, South Latitude, Cananéia, Brasil). Comparisons with values of primary production for other tropical and temperate environments have been made. Further lines of work are indicated.
Untersuchungen des CO2–Stoffwechsels submerser höherer Wasserpflanzen im Fließgewässer unter Einsatz eines fahrbaren Infrarot‐Gasanalysator‐Labors
Authors: Horbach W. , Hornig L. , Weise G. 
Published: February 2007

Investigations on the CO2 Balance of Submerged Water Plants in Running Water By Means of a Motile Laboratory for Infrared Gas AnalysisThe CO2‐balance of the submerged water mosses Hygrohypnum ochraceum f. obtusifolia, Amblystegium riparium, Amblystegium riparium f. fontinaloides and of Potamogeton trichoides (Potamogetonaceae) was investigated by means of a transportable laboratory for infrared gas analysis. The experiments were carried out in the river Zwickauer Mulde by means of glass vessels exposed to the water body. The device for continuous measuring CO2 exchange was operated by pumping air through the vessels containing 4 l of water. The water plants exhibited a distinct day night rhythm of CO2 turnover. In some cases river water alone, which had percolated a tampon of Perlon fibres, also showed a considerable day night rhythm of CO2 turnover which had to be attributed to phytoplankton and suspended periphyton organisms, the activity of which is superimposed above the photosynthetic activity of the macrophytes. Measurement of the CO2 balance of submerged plants in water containing microphytes can only be attributable to the macrophytes if the time of exposition does not exceed one day.
A Preliminary Approach to the Use of the Isotopic Ratio 13C/12C for the Evaluation of Mineralization in Aquatic Environments
Authors: Bertoni R. , Melchiorri‐Santolini U. , Létolle R. , Lugrin M. , Olive Ph. 
Published: February 2007

Abstract12C/13C ratio is used as natural tracer for the estimation of the mineralizing activity of pelagic bacteria.Attention is particularly given to the variations of the isotopic ratio of the inorganic carbon produced by the microbial oxidation in comparison with the ratio of the dissolved organic matter.
The Effects of Hydrostatic Pressure on Living Aquatic Organisms III. Behavior and Tolerance of Euplanktonic Organisms to Increased Hydrostatic Pressure
Authors: George Robert Y. , Marum James P. 
Published: February 2007

AbstractIn the habitat temperature, northern cold planktonic species seem more resistant to pressure than related southern warm species. Generally, a prolonged “hyperactivity phase” was recognized between moderate and high hyperbaric levels in most planktonic species. Descriptions of reactions of various planktonic species to increasing pressure are given with reference to stimulated activity (R1), onset of tetany (T), and inactivity (I). On the basis of LD50 levels, the 16 planktonic species show high, moderate, low or extremely low tolerance to one hour stress conditions of high hydrostatic pressure.
The Effects of Hydrostatic Pressure on Living Aquatic Organisms VI. Organic Complexity and Hydrostatic Pressure Sensitivity
Authors: Menzies Robert J. , Selvakumaran M. 
Published: February 2007

AbstractForty species of aquatic animals belonging to 14 phyla of various levels of organic complexity were examined with reference to their ability to survive increasing hydrostatic pressure. The results of these experiments lead us to seriously question the commonly stated and often quoted hypothesis that there is an inverse relationship between pressure resistance and the complexity of organisms.
The Effects of Hydrostatic Pressure on Living Aquatic Organisms VII. Size and Pressure Effects
Authors: Selvakumaran M. , Hodson Robert , Menzies Robert J. 
Published: February 2007

AbstractA survey of the pressure resistance of aquatic animals in different stages of their life cycle shows that adults generally are more tolerant of pressure than the egg and nauplii, but older adults appear less pressure resistant than younger adults. Data on many species of aquatic animals of different size shows no correlation between size and pressure resistance. It is concluded that size is not a special determinant in the successful deep‐sea colonization of shallow‐water animals and this is consonant with the fact of occasional large deep‐sea species whereas the average size is quite small in comparison with littoral species.
The Dual Origin of the Black Sea Foraminifera
Authors: Tufescu Mircea 
Published: February 2007

AbstractEvidence is given supporting the possibility of survival in the modern Black Sea of descendents of Miocene Pontic foraminiferal populations. This evidence includes the present existence of Foraminifera in the Aral and Caspian Seas, the existence of pockets of species in the Paratethys area in waters long isolated from any seas, the existence in the Golovitza Lagoon of Foraminifera living at salinities lower than those that are thought to have existed in the Pontic Basin during its lacustrine period, and evidence from zoogeography. It is shown that there are morphological, ecological and physiological modifications in these aboriginal populations as compared to populations of the same species living in the Mediterranean. In addition to these aboriginal populations, evidence is given for three invasions of Foraminifera from the Mediterranean during geological periods when the Black and Mediterranean Seas were merged.