bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abundance of salmon carcasses at the upper reach of a fish trap
Authors: Ito Tomiko , Nakajima Miyuki , Shimoda Kazutaka 
Published: December 2004

AbstractAbundance, biomass and retention of salmon carcasses (Oncorhynchus keta and O. masou masou) were studied in a spring‐fed tributary, the Naibetsu River, Chitose River system, Hokkaido, northern Japan, in 1998–2003, where almost all adult salmon were caught for a salmon enhancement program by a fish trap at the lower reach every fall. The abundance and biomass fluctuated seasonally, with two peaks in fall and winter, and annually. The total number of carcasses in fall was significantly correlated with the highest water level at lower reach in fall, indicating that the adult salmon swam over the trap at flood. Carcass abundance in winter may depend on the population size spawned in the wild at the upper reach, since the trap was removed in this season. Since the large wood debris and gravel were absent or scarce, many carcasses were lost from the study site within 20 days and a few carcasses remained over 31 days. Carcass removal by some terrestrial animals from the study site was detected.
Limit values for decomposition and convergence process of lignocellulose fraction in decomposing leaf litter of 14 tree species in a cool temperate forest
Authors: Osono Takashi , Takeda Hiroshi 
Published: December 2004

AbstractWe examined limit values for decomposition and lignocellulose index (LCI, the ratio of acid‐soluble holocellulose to acid‐soluble holocellulose plus acid‐insoluble lignin and lignin‐like substances) in leaf litter decomposition of 14 tree species over 3 years. The study was carried out on upper (moder) and lower parts (mull) of a forest slope that showed different humus accumulation forms in a cool temperate forest in Japan. Limit values for accumulated mass loss of litter ranged from 46.8% to 94.1% and were not different between the sites. Limit values were positively correlated to initial LCI and lignin content. Final values of LCI of 14 litter types at the end of the study period showed a convergent trend among litter types at 0.25–0.26 as compared to their initial values (0.41 mean). The final LCI was not different between the sites. A review of limit values and initial and final values of LCI in leaf litter of temperate and boreal forests indicated that the limit values and final LCI in litter types in Japan were lower than those in Europe and North America, which can be primarily ascribed to lower initial LCI in Japan.
An aphid‐ant interaction: effects on different trophic levels
Authors: Renault C. K. , Buffa L. M. , Delfino M. A. 
Published: December 2004

AbstractThe interaction between the aphid Aphis coreopsidis (Thomas) (Hemiptera, Aphididae) and the ant Camponotus sp.1 (Hymenoptera, Formicidae) on the plant Bidens pilosa L. (Asteraceae) was studied. We manipulated the presence of ants and other insects to understand the effects of this aphid‐ant interaction on: (a) the growth of A. coreopsidis population, (b) the seed production of B. pilosa, (c) the density of predator spiders. The growth of the A. coreopsidis population was positively affected by attending ants, showing greater increase on ant‐present control plants than on ant‐excluded plants. The density of aphids on control plants was positively correlated with the density of attending ants, while the density of aphids on ant‐excluded plants was positively correlated with the density of spiders. Plants with ants had a significantly lower quantity of viable seeds than those without ants. These results show that: (a) the presence of Camponotus ants reduces the number of predator spiders on B. pilosa, (b) the population of A. coreopsidis increases when attended by the ants, (c) this increase in aphid density as a result of ant attendance reduces the number of viable seeds of B. pilosa, and thus (d) an interspecific interaction between two species can have an indirect negative fitness effect on other partners.
Food habits of sika deer in the Shiranuka Hills, eastern Hokkaido: a northern example from the north–south variations in food habits in sika deer
Authors: Campos‐Arceiz Ahimsa , Takatsuki Seiki 
Published: December 2004

AbstractSeasonal changes in the composition of the diet of the sika deer population in the Shiranuka Hills, eastern Hokkaido, in 1998 were determined by fecal analyses. The deer were dependent on Sasa nipponica, a dwarf bamboo, throughout the year, particularly in winter when it accounted for as much as 77.7% of the diet. It accounted for 33.1% and 45.6% in spring and summer, respectively, and this decreased to 12.2% in autumn. Besides S. nipponica, all the graminoid categories accounted for large amounts (66–96.7%), while dicotyledonous plants accounted for little (3–8%) except in autumn when they accounted for 31%. The strong dependence of the Shiranuka population on graminoids was different from other Hokkaido deer populations, for example the population from Ashoro/Onbetsu and the extremely high density population on Nakanoshima Island. In spite of these differences, food for all Hokkaido sika deer was poor in winter. Along the north–south geographical cline in the food composition of sika deer along the Japanese archipelago, the Shiranuka population was positioned as a grazer type, in contrast to the southern populations. However, it is important to note that variations are great among local populations in Hokkaido.
Middle Pleistocene Mollusks from St. Lawrence Island and their Significance for the Paleo-Oceanography of the Bering Sea
Authors: Hopkins David M. , Rowland Robert W. , Patton William W. 
Published: December 2004

Drift, evidently of Illinoian age, was deposited on St. Lawrence Island at the margin of an ice cap that covered the highlands of the Chukotka Peninsula of Siberia and spread far eastward on the continental shelf of northern Bering Sea. Underlying the drift on the northwestward part of the island are mollusk-bearing beds deposited during the Kotzebuan Transgression.
A comparison of mollusk faunas from St. Lawrence Island, Chukotka Peninsula, and Kotzebue Sound suggests that the present northward flow through Bering and Anadyr Straits was reversed during the Kotzebuan Transgression. Cold arctic water penetrated southward and southwestward bringing an arctic fauna to the Gulf of Anadyr. Warmer Pacific water probably entered eastern Bering Sea, passed eastward and northeastward around eastern and northern St. Lawrence Island, and then became entrained in the southward currents that passed through Anadyr Strait.
Interglacial and Postglacial Climates: The Pollen Record
Authors: Wright Herbert E. 
Published: December 2004

Pollen studies of the four European interglacial intervals indicate a strong similarity in vegetational sequence: a pretemperate phase (I) marks the late glacial, early temperate (II) and late temperate (III) phases mark the interglacial proper, and a posttemperate phase (IV) represents the beginning of the next cold period. A grossly similar record is now known for the last interglacial (Sangamon) of central and southeastern United States. The Holocene sequence in both Europe and America are completely typical of the interglacial sequence, although much more is known of the geographic variations.Estimates for the duration of the interglacials range from 10,000 to more than 30,000 yr, according to counts of the annually laminated sediments (organic varves).The Holocene has already run a course of at least 10,000 yr. If it is like earlier interglacials, it will end soon, giving way to gradually developing cold conditions, which may not lead to glacial maxima for tens of thousands of years.
Holocene Interglacial in Central Europe and its Land Snails
Authors: Ložek Vojen 
Published: December 2004

The primeval forests of Central Europe are still inhabited by relatively ecologically demanding, thermo- and hydrophilous snail fauna of interglacial character, which differs from the assemblages of Holocene climatic optimum and of the last interglacial optimum by the absence of some southern (exotic) elements.In the deforested areas inhabited by man, the less demanding mesic to steppe fauna predominates. It differs from analogous early glacial communities only in comprising modern, climatically demanding species, which are unknown from the Pleistocene. They found a suitable habitat in Central Europe thanks to human interference. The dwindling formation of tufa spring deposits and their partial destruction both in occupied and unoccupied areas indicate that the Holocene warm interval is in the late phase.The recent slope deposits are reminiscent of early glacial sections both by their lithology and fauna reflecting existence of large open spaces. Whereas in early glacials the deforestation resulted from the change of climate, the recent one is almost entirely a product of man.In assessing the present-day position within the interglacial cycle, we should take into consideration all these conclusions and always keep in mind the share of man's influence in the development observed.
End of the Last Interglacial in the Loess Record
Authors: Kukla George J. , Kočí Alois 
Published: December 2004

In the loess series of Central Europe the last interglacial is recorded by the parabrownearth soil accompanied by land snails and pollen of thermophilous deciduous forests. The termination of forest environment is marked by restricted eolian sedimentation and development of chernozemic steppe soil, followed in turn by rapid deposition of calcareous air-borne silt in the so called “Marker” horizon. Hillwash loams and loess interrupted by the weak rendzina-type soil B1f were then formed. The sequence is overlain by the interstadial soil complex which is correlated with the Barbados II Terrace because of its stratigraphic position and warmth-loving snail fauna. Through most of the section bracketed by the interglacial and interstadial soils, the sediments display the reversed declination but positive inclination. The top of the reversed interval is here informally called the Brno magnetostratigraphic horizon. It correlates reasonably well with the upper boundary of the Blake event estimated to be 108,000 yr old.The vertebrate and the snail faunas of chernozemic soil and of the loess together with the pedogenetic character of strata point to the harsh continental climate with the large temperature variation, dry seasons and partly, with torrential summer rains.If the remarkably periodic deposition of loess series has to continue, following the pattern observed through the last 350,000 yr or so, then the shift to expressed continental climate in this part of Europe is to be expected soon.
Wildfire in the Taiga of Alaska
Authors: Viereck Leslie A. 
Published: December 2004

AbstractThe taiga of Alaska consists of a vegetation mosaic resulting primarily from past wildfires. Today, both lightning- and man-caused wildfires burn an average of 400,000 hectares annually, creating vast areas of successional ecosystems. However, although the number of reported fires is increasing, fire control is becoming more effective in limiting the average size of fires and the total area burned. One of the important influences of fire in the taiga ecosystem is its effect on permafrost and the soil nutrient cycle. Construction of firelines in permafrost areas has a greater effect on soil erosion and siltation than does the fire itself. Some wildlife species, such as moose and snowshoe hare, depend upon fire and its resultant successional plant communities, whereas fire may have deleterious effects on caribou winter range. Fire has both positive and negative effects on esthetic and recreational values. Fire has always been a part of the Alaskan taiga ecosystem; if it is totally excluded from the environment, some major ecological changes will result. Fire-suppression alternatives are discussed and additional research on fire effects suggested.
The Ecological Role of Fire in Sierran Conifer Forests: Its Application to National Park Management
Authors: Kilgore Bruce M. 
Published: December 2004

AbstractThe impact of fire on the environment of the various Sierran conifer forests varies with intensity and frequency. Generally, however, fire (1) prepares a seedbed; (2) cycles nutrients within the system; (3) adjusts the successional pattern; (4) modifies conditions affecting wildlife; (5) influences the mosaic of age classes and vegetation types; (6) alters the numbers of trees susceptible to disease and insects; and (7) both reduces and creates fire hazards. Natural fire frequency apparently coincides with levels of fuel accumulation that result in burns of relatively low intensity at frequent intervals. This may average 8 yr in mixed conifer forests, although frequencies from 4 to 20 yr or more are found in particular sites.In all probability, giant sequoia and various pines of the Sierra survive today because of the role fire plays in the various forest types. National Park Service management policies are aimed at restoring fire, as nearly as possible, to its natural role in Sierran conifer forests. This is being accomplished by prescribed burning at lower and middle elevation types and by allowing lightning fires to burn in higher elevation forests.
Late Pleistocene History of the North Pacific: Evidence from a Quantitative Study of Radiolaria in Core V21-173
Authors: Sachs Harvey Maurice 
Published: December 2004

AbstractObjective quantitative estimates of paleo-oceanographic conditions in the North Pacific can be made by analyses of radiolarian assemblages. With appropriate computation, transfer functions developed in a study of surface sediments can be used to estimate oceanographic conditions in cores containing late Pleistocene radiolarian faunas. Analysis of core V21-173 indicates that conditions as warm as the Holocene were rare during the past 800,000 yr, and that the region experienced marked near-surface temperature drops correlative with Caribbean and continental records for the past 250,000 yr. A major world-wide warm event at about 400,000 yr is also indicated.
Formation of the Neoglacial Surge Moraines of the Klutlan Glacier, Yukon Territory, Canada
Authors: Driscoll Fletcher G. 
Published: December 2004

AbstractThe Klutlan Glacier is a valley glacier 82-km long emerging from the Icefield Ranges of the St. Elias Mountains. It is one of at least 200 surging glaciers identified in western North America. During about the past 1200 yr, the glacier has deposited at its terminus a series of at least 7 surge-related Neoglacial ice-cored moraines. Lithologic characteristics of the Klutlan moraines suggest that they have resulted principally from the surging of the tributary Nesham Glacier, which periodically injects a lobe of medial and lateral moraines and the underlying ice into a more slowly moving Klutlan ice stream. Subsequent surges of the main ice carry the Nesham surge lobes to the Klutlan terminus as discrete geomorphic features. For the past 400 yr a Nesham lobe has reached the Klutlan terminus at approximately 80-yr intervals.
Soil Development on Recent End Moraines of the Klutlan Glacier, Yukon Territory, Canada
Authors: Jacobson G. L. , Birks H. J. B. 
Published: December 2004

AbstractData on soils with six Neoglacial moraines of the Klutlan Glacier have been compared with those from moraines at the warm, moist coastal site of Glacier Bay, 160 km south. Percentage organic matter increases rapidly for the first 100 to 150 yr of soil development and then continues to rise gradually for the next 100 yr. Soil pH falls from 8.0 in recent till to approximately 6.0 in 200-yr-old soils. Nitrogen levels in the mineral soil increase from near zero in recent tills to 0.7% in soils 175–200 yr old; organic horizons of soils associated with spruce forests in later successional stages contain approximately 1% nitrogen. Concentrations of certain inorganic phosphate ions in the different-aged soils increase continually throughout the succession. Data for nine chemical variables were subjected to a principal components analysis; the major pattern in the data reflects the differences between soils of low organic content and high pH present in early successional stages, and nutrient-rich soils with high organic content and low pH present after succession has progressed toward the spruce forest. These trends in soil development with time are strikingly similar to those reported from Glacier Bay, except that the changes in soil properties appear to be delayed by 50–100 yr at the Klutlan terminus. Although numerous signs of nitrogen deficiency have been identified in plants growing on new soils at Glacier Bay, none was observed visually in living plants or in nutrients measured in samples of foliage from three plant taxa (Epilobium latifolium, Salix spp., and Populus balsamifera) taken from the Klutlan moraines. Concentrations of nitrogen and other nutrients (Ca, Mg, K, total P) in the foliage samples show no clear trends with increasing soil development. Low temperatures, a short growing season, and very low mean annual precipitation probably limit plant growth and account for the delayed soil development on the Klutlan moraines.
Electron Microprobe Correlation of Tephra Layers from Eastern Mediterranean Abyssal Sediments and the Island of Santorini
Authors: Federman Alan N. , Carey Steven N. 
Published: December 2004

AbstractFive widespread tephra layers are found in late Quaternary sediments (0–130,000 yr B.P.) of the Eastern Mediterranean Sea. These layers have been correlated among abyssal cores and to their respective terrestrial sources by electron-probe microanalysis of glass and pumice shards. Major element variations are sufficient to discriminate unambiguously between the five major layers. Oxygen isotope stratigraphy in one of the cores studied was used to data four of the five layers. Two of the widespread layers are derived from explosive eruptions of the Santorini volcanic complex: the Minoan Ash (3370 yr B.P.) and the Acrotiri Ignimbrite (18,000 yr B.P.). An additional layer, found in one core only, is most likely correlated to the Middle Pumice Series of Santorini (approximately 100,000 yr B.P.). Two layers are correlated to deposits on the islands of Yali and Kos and date to 31,000 and 120,000 yr B.P., respectively. One layer originated from the Neapolitan area of Italy 38,000 yr B.P.
Late-Quaternary Vegetation History at White Pond on the Inner Coastal Plain of South Carolina
Authors: Watts W. A. 
Published: December 2004

AbstractAt White Pond near Columbia, South Carolina, a pollen assemblage of Pinus banksiana (jack pine), Picea (spruce), and herbs is dated between 19,100 and 12,800 14C yr B.P. Plants of sandhill habitats are more prominent than at other sites of similar age, and pollen of deciduous trees is infrequent. The vegetation was probably a mosaic of pine and spruce stands with prairies and sand-dune vegetation. The climate may have been like that of the eastern boreal forest today. 14C dates of 12,800 and 9500 yr B.P. bracket a time when Quercus (oak), Carya (hickory), Fagus (beech), and Ostrya-Carpinus (ironwood) dominated the vegetation. It is estimated that beech and hickory made up at least 25% of the forest trees. Conifers were rare or absent. The environment is interpreted as hickory-rich mesic deciduous forest with a climate similar to but slightly warmer than that of the northern hardwoods region of western New York State. After 9500 yr B.P. oak and pine forest dominated the landscape, with pine becoming the most important tree genus in the later Holocene.
On the Design of Paleoenvironmental Data Networks for Estimating Large-Scale Patterns of Climate
Authors: Kutzbach J. E. , Guetter P. J. 
Published: December 2004

AbstractGuidelines are determined for the spatial density and location of climatic variables (temperature and precipitation) that are appropriate for estimating the continental- to hemispheric-scale pattern of atmospheric circulation (sea-level pressure). Because instrumental records of temperature and precipitation simulate the climatic information that is contained in certain paleoenvironmental records (tree-ring, pollen, and written-documentary records, for example), these guidelines provide useful sampling strategies for reconstructing the pattern of atmospheric circulation from paleoenvironmental records. The statistical analysis uses a multiple linear regression model. The sampling strategies consist of changes in site density (from 0.5 to 2.5 sites per million square kilometers) and site location (from western North American sites only to sites in Japan, North America, and western Europe) of the climatic data. The results showed that the accuracy of specification of the pattern of sea-level pressure: (1) is improved if sites with climatic records are spread as uniformly as possible over the area of interest; (2) increases with increasing site density-at least up to the maximum site density used in this study; (3) is improved if sites cover an area that extends considerably beyond the limits of the area of interest. The accuracy of specification was lower for independent data than for the data that were used to develop the regression model; some skill was found for almost all sampling strategies.
Relations entre les données isotopiques océaniques et l'histoire des grandes faunes européennes plio-pleistocenes
Authors: Bonifay Marie-Françoise 
Published: December 2004

AbstractCette étude est un premier essai de corrélation entre les résultats déjà obtenus sur les grandes faunes plio-pléistocènes européennes et les stades climatiques majeurs (tant froids que tempérés) mis en évidence dans les courbes isotopiques océaniques. Ce sont les phases froides en particulier qui expliquent souvent la disparition de certaines espèces, puis les phénomènes climatiques s'accentuant, leur remplacement par d'autres groupes. Un parallélisme assez évident se fait jour entre la succession en Europe des associations de grandes faunes et les phases paléoclimatiques révélées par le domaine marin, avec cependant une certaine dissension pour les périodes récentes. Face à la grande diversification des faunes quaternaires, dues vraisemblablement à la multiplicité des zones climatiques, et aux résultats des carottes océaniques qui nous fournissent seulement des données globales, seules les biostratigraphies régionales permettront de reconstituer avec précision les différents biotopes.This study is the first test of correlation between the results obtained on the large Plio-Pleistocene European faunas and the main climatic stages (cold as well as temperate) demonstrated in marine isotopic records. In particular, there are cold stages which often explain the disappearance of some species, as well as climatic events that promote the substitution of some species by other groups. A rather evident parallelism appears between the European succession of large faunal associations and paleoclimatic stages revealed in oceanic areas, but some discordance occurs in the later periods. Faced with the great diversification of the Quaternary faunas, probably due to the multiplicity of climatic environments, and with global information from oceanic records, only local biostratigraphic studies will allow precise reconstruction of the different biotopes.
Cave Sites, Faunal Analysis, and Big-Game Hunters of the Great Basin: A Caution
Authors: Mc Guire Kelly R. 
Published: December 2004

AbstractDeposits of inferred natural origin excavated at Mineral Hill Cave, north-central Nevada, exhibit a similarity to the reported evidence for “Big-Game Hunters” from cave sites in the Great Basin. Split bone and charcoal were observed throughout the deposits. In addition, the remains of a number of animal taxa including several Pleistocene genera, which are considered to have been of economic importance, were recovered from the deposits. These findings suggest that the role of natural processes in cave deposition is of crucial importance in understanding cave-site archaeology.