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River Valley (river + valley)
Kinds of River Valley Selected AbstractsHYDROLOGICAL EFFECTS OF AN UNCONTROLLED FLOWING WELL, RED RIVER VALLEY, NORTH DAKOTA, USA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2004Philip J. Gerla ABSTRACT: In areas of the Red River Valley that overlie permeable Paleozoic sediments, wetlands and salinization have developed where unregulated flowing wells discharge brackish water. Field data were collected to assess the fate of water and salt from a well 25 km northwest of Grand Forks. Drilled during the drought of the 1930s, discharge was used to replenish water in a small oxbow pond used by livestock. The unregulated well discharges about 56 m3/day, measured since 1993. This discharge exceeds ground water flow from the site, thereby forming a ground water mound with a maximum height of 1 m and a diameter of about 300 m. Most soil and underlying sediments near the well have a hydraulic conductivity of 0.3 m3/day. Flow net analysis suggests that less than 25 percent infiltrates, with the remaining water lost to surface flow and evapotranspiration (ET). Evapotranspiration and slow infiltration has led to increased salinization, with shallow soils exhibiting EC to 500 milliSiemens/m. The most pronounced soil salinization occurs along the margins of the oxbow pond and meander scars. Wetland vegetation with low diversity comprises three zones, with species associations similar to those of closed basin prairie potholes to the west. [source] The Journal of the Society for Conservation Biology A global community of conservation professionalsCONSERVATION BIOLOGY, Issue 2 2006Article first published online: 27 MAR 200 Cover: Old-growth forest of the Hoh River Valley, Olympic National Park, Washington (U.S.A.). For decades the U.S. Pacific Norwest has been a center of controversy over logging and endangered species. This special section explores progress made by the Northwest Forest Plan,a global example of land-use planning,a decade after it was established to end the stalemate over logging and endangered species. Authors include some of the key architects involved in its creation and implementation. Photo by Kevin Schafer. See pages 274,374. [source] Relating streamflow characteristics to specialized insectivores in the Tennessee River Valley: a regional approach,ECOHYDROLOGY, Issue 4 2008Rodney R. Knight Abstract Analysis of hydrologic time series and fish community data across the Tennessee River Valley identified three hydrologic metrics essential to habitat suitability and food availability for insectivorous fish communities in streams of the Tennessee River Valley: constancy (flow stability or temporal invariance), frequency of moderate flooding (frequency of habitat disturbance), and rate of streamflow recession. Initial datasets included 1100 fish community sites and 300 streamgages. Reduction of these datasets to sites with coexisting data yielded 33 sites with streamflow and fish community data for analysis. Identification of critical hydrologic metrics was completed using a multivariate correlation procedure that maximizes the rank correlation between the hydrologic metrics and fish community resemblance matrices. Quantile regression was used to define thresholds of potential ranges of insectivore scores for given values of the hydrologic metrics. Increased values of constancy and insectivore scores were positively correlated. Constancy of streamflow maintains wetted perimeter, which is important for providing habitat for fish spawning and increased surface area for invertebrate colonization and reproduction. Site scores for insectivorous fish increased as the frequency of moderate flooding (3 times the median annual streamflow) decreased, suggesting that insectivorous fish communities respond positively to less frequent disturbance and a more stable habitat. Increased streamflow recession rates were associated with decreased insectivore scores. Increased streamflow recession can strand fish in pools and other areas that are disconnected from flowing water and remove invertebrates as food sources that were suspended during high-streamflow events. Copyright © 2008 John Wiley & Sons, Ltd. [source] Using a Geographic Information System to identify areas with potential for off-target pesticide exposureENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2006Thomas G. Pfleeger Abstract In many countries, numerous tests are required as part of the risk assessment process before chemical registration to protect human health and the environment from unintended effects of chemical releases. Most of these tests are not based on ecological or environmental relevance but, rather, on consistent performance in the laboratory. A conceptual approach based on Geographic Information System (GIS) technology has been developed to identify areas that are vulnerable to nontarget chemical exposure. This GIS-based approach uses wind speed, frequency of those winds, pesticide application rates, and spatial location of agricultural crops to identify areas with the highest potential for pesticide exposure. A test scenario based on an incident in Idaho (USA) was used to identify the relative magnitude of risk from off-target movement of herbicides to plants in the conterminous United States. This analysis indicated that the western portion of the Corn Belt, the central California valley, southeastern Washington, the Willamette Valley of Oregon, and agricultural areas bordering the Great Lakes are among those areas in the United States that appear to have the greatest potential for off-target movement of herbicides via drift. Agricultural areas, such as the Mississippi River Valley and the southeastern United States, appears to have less potential, possibly due to lower average wind speeds. Ecological risk assessments developed for pesticide registration would be improved by using response data from species common to high-risk areas instead of extrapolating test data from species unrelated to those areas with the highest potential for exposure. [source] Geophysical and geochemical investigations at two early copper age settlements in the Körös River Valley, Southeastern HungaryGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 8 2007Richard W. Yerkes Geophysical and geochemical analyses conducted at the Early Copper Age [source] Geoarchaeology of the Kostenki,Borshchevo sites, Don River Valley, RussiaGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 2 2007Vance T. Holliday The Kostenki,Borshchevo localities include 26 Upper Paleolithic sites on the first and second terraces along the west bank of the Don River, near Voronezh on the central East European Plain. Geoarchaeological research from 2001 through 2004 focused on sites Kostenki 1, 12, and 14, with additional work at Kostenki 11 and 16, and Borshchevo 5. The strata are grouped into three units (bottom up): Unit 1, > 50 ka, consists of coarse alluvium (representing upper terrace 2 deposits) and colluvium, overlain by fine-grained sediments. Unit 2 includes archaeological horizons sealed within two sets of thin lenses of silt, carbonate, chalk fragments, and organic-rich soils (termed the Lower Humic Bed and Upper Humic Bed) dating 50,30 ka. Separating the humic beds is a volcanic ash lens identified as the Campanian Ignimbrite Y5 tephra, dated elsewhere by Ar/Ar to ca. 40 ka. The humic beds appear to result from the complex interplay of soil formation, spring deposition, slope action, and other processes. Several horizons buried in the lower part of Unit 2 contain Upper Paleolithic assemblages. The springs and seeps, which are still present in the area today, emanated from the bedrock valley wall. Their presence may account for the unusually high concentration of Upper Paleolithic sites in this part of the central East European Plain. Unit 3, < 30 ka, contains redeposited loess with a buried soil (Gmelin Soil) overlain by a primary full-glacial loess with an associated Chernozem (Mollisol), forming the surface of the second terrace. © 2007 Wiley Periodicals, Inc. [source] Archaeological site distribution by geomorphic setting in the southern lower Cuyahoga River Valley, northeastern Ohio: Initial observations from a GIS databaseGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 8 2004Andrew Bauer In this study, we compiled unpublished archival documentation of archaeological site locations from the southern part of the Cuyahoga River Valley in northeastern Ohio, USA, registered at the State of Ohio Historic Preservation Office into a Geographic Information Systems (GIS) database. Using digitized soil shapefiles to generate a geomorphic data layer, we assessed the spatial and temporal distribution of 79 known archaeological sites by landform association. This digital compilation indicates that Woodland period, Late Prehistoric, and Historic sites occur in most geomorphic settings along the river valley. In contrast, Paleoindian and Archaic sites only occur on Wisconsinan cut terraces and in upland interfluve settings, indicating that most of these documented sites are in primary contexts and have not been reworked. We discuss the distribution of archaeological sites in the study region as a function of various factors, including cultural activities, taphonomic processes, landform development, and the nature and extent of the original archaeological surveys. Observed spatial patterns of known sites clearly reflect local geomorphological controls; artifactual contexts from the earlier prehistoric periods are underrepresented in the database. We conclude that additional site surveys, as well as the excavation and documentation of new sites in this part of Ohio, are required to understand local prehistoric economies and to ascertain patterns of culturally mediated land use. © 2004 Wiley Periodicals, Inc. [source] The hidden record: Late Holocene landscapes and settlement archaeology in the Lower Ohio River ValleyGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 2 2002C. Russell Stafford From extensive backhoe trenching and coring in the Great Miami,Ohio River confluence region, in conjunction with a large suite of radiocarbon ages, we have identified large tracts of late Holocene alluvium. Thick blankets of Historic alluvium (post-settlement) may also cover levees of the Ohio River. In conjunction with other studies in the Outer Bluegrass Region of the lower Ohio River valley, it is possible to document an association between floodplain Mollisols, Inceptisols, and Entisols and late Holocene-aged landforms. Levees appear to have stabilized between 1000 and 2000 yr B.P. Although buried soils are rare, archaeological materials were ubiquitous in late Holocene Landform Sediment Assemblages. Because a substantial volume of valley fill is late Holocene in age, Woodland sites of all types are frequently buried, and Fort Ancient sites may be buried by Historic alluvium. Therefore, if Woodland or later settlement studies in this region are based on surface evidence alone, they are likely to be biased. © 2002 John Wiley & Sons, Inc. [source] Major neotectonic features of eastern Marmara region, Turkey: development of the Adapazar,,Karasu corridor and its tectonic significanceGEOLOGICAL JOURNAL, Issue 2 2004nç Yi Abstract Eastern Marmara region consists of three different morphotectonic units: Thrace,Kocaeli Peneplain (TKP) and Çamda,,Akçakoca Highland (ÇAH) in the north, and Armutlu,Almac,k Highland in the south of the North Anatolian Fault Zone (NAFZ). The geologic-morphologic data and seismic profiles from the Sakarya River offshore indicate that the boundary between the TKP in the west and ÇAH in the east is a previously unrecognized major NNE,SSW-trending strike-slip fault zone with reverse component. The fault zone is a distinct morphotectonic corridor herein named the Adapazar,,Karasu corridor (AKC) that runs along the Sakarya River Valley and extends to its submarine canyon along the southern margin of the Black Sea in the north. It formed as a transfer fault zone between the TKP and ÇAH during the Late Miocene; the former has been experiencing extensional forces and the latter compressional forces since then. East,West-trending segments of the NAFZ cuts the NE,SW-trending AKC and their activity has resulted in the formation of a distinct fault-bounded morphology, which is characterized by alternating E,W highlands and lowlands in the AKC. Furthermore, this activity has resulted in the downward motion of an ancient delta and submarine canyon of the Sakarya River in the northern block of the NAFZ below sea level so that the waters of the Black Sea invaded them. The NE,SW-trending faults in the AKC were reactivated with the development of the NAFZ in the Late Pliocene, which then caused block motions and microseismic activities throughout the AKC. Copyright © 2004 John Wiley & Sons, Ltd. [source] Features of cross-Pacific climate shown in the variability of China and US precipitationINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 13 2005Q. Li Abstract In this study, we have analyzed the climate features of China and the United States with a focus on the differences, similarities, connectivity, and predictability of precipitation and the relationships between precipitation and large-scale patterns of natural variability. China precipitation is characterized by large seasonality, with a maximum in summer and a minimum in winter. The seasonality of precipitation shows an increasing linear tendency in northwest China, with a change of about 20% from 1901 to 1998. A relatively weaker increasing tendency also appears in the Big Bend of Yellow River (BBYR) and the Tibetan Plateau, while southwest China experiences a decreasing tendency. Furthermore, the seasonality in the BBYR shows particularly significant interdecadal variability, while that of southern and eastern China has decreased slightly in the recent decades. Compared to China, the United States as a whole has less precipitation in summer but more precipitation in other seasons. Here, the seasonality of precipitation is only about 24% of that in China. The annual mean precipitation is 64.1 mm per month in the United States, compared to 54.6 mm per month in China. The seasonality of precipitation exhibits a decreasing tendency in the southeast, Pacific Northwest, and Gulf Coast and an increasing tendency in the Great Lakes. The seasonality in the Great Plains exhibits large interdecadal variability. The long-term variations of precipitation are highly seasonally dependent. In summer, a decreasing trend is observed in north China and an increasing trend is found in eastern-central China. However, these trends are almost opposite in spring. In addition, the fall precipitation decreases with time nearly everywhere in China except for the middle and lower reaches of the Yangtze River Valley. Results also indicate that the El Niño/Southern Oscillation (ENSO), the Arctic Oscillation (AO), the North Atlantic Oscillation (NAO), the Pacific Decadal Oscillation (PDO), and the North Pacific (NP) fluctuation affect strongly the variations of China and US precipitation. Although these influences vary with regions and seasons, we in particular emphasize the importance of AO and NAO for China precipitation and NP and PDO for US precipitation. In fall, ENSO and PDO are the two phenomena that influence predominantly precipitation variability in both China and the United States We also identify the common phenomena that influence China and US regional precipitation and provide a better understanding of the physical mechanism for precipitation variability through the associated changes in atmospheric and oceanic conditions. Furthermore, we develop a linear regression model, based on multiple regression method by combining the regionally and seasonally varying impacts, to increase the skill of precipitation prediction. Copyright © 2005 Royal Meteorological Society [source] Murder or mortuary behaviour?INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2003An Iron Age enigma from Northeast Thailand Abstract During the excavation of the Iron Age site of Noen U-Loke, in the Mun River Valley, northeast Thailand, in 1998 an unusual case of possible fatal cranial trauma in an elderly woman was recovered. Her skull was cleaved across the centre from side to side. The woman was buried with her head inside a ceramic pot, which is unusual for the site, but with jewellery similar to that in other burials. She was interred in a large cluster of graves, with a high proportion of infants and children. Her burial treatment suggests that she was not being treated punitively. The position of the mandible shows that the cleavage is not a postmortem artifact but it is not possible to determine the reason for it or whether it was the cause of her death or occurred immediately afterward. It is an unusual and intriguing enigma. Copyright © 2003 John Wiley & Sons, Ltd. [source] A probable case of metastatic carcinoma from the late prehistoric eastern Tennessee River ValleyINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2002Maria Ostendorf Smith Abstract There are few described cases of metastatic carcinoma from the prehistoric eastern United States and none primarily differentially diagnosed from the southeast. A mature adult female exhibiting several large lytic cranial lesions suggestive of neoplastic disease was identified in a late prehistoric Mississippian Period (AD 1200,1600) context. Burial 371 is from Ledford Island, a Mouse Creek phase (AD 1400,1500) site from the Chickamauga Reservoir of southeastern Tennessee. It is the only case in this reservoir (total adult n = 843). The radiographs of the otherwise asymptomatic postcranium yielded radiolucencies in both proximal femora, both medial clavicles, the sternum, the surviving humeral metaphysis and fragmentary innominate. The locations are all consistent with metastasized carcinoma. The identity of the possible primary lesion is argumentative. Age, sex and the mixed nature of the osseous response are consistent with carcinoma of the breast but not to the exclusion of bronchogenic, thyroid, or kidney cancers. Copyright © 2002 John Wiley & Sons, Ltd. [source] Genetic Diversity of Landraces in Gossypium arboreum L. Race sinense Assessed with Simple Sequence Repeat MarkersJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 9 2006Wang-Zhen Guo Abstract Asiatic cotton (Gossypium arboreum L.) is an "Old World" cultivated cotton species, the sinense race of which is planted extensively in China. This species is still used in the current tetraploid cotton breeding program as an elite germplasm line, and is also used as a model for genomic research in Gossypium. In the present study, 60 cotton microsatellite markers, averaging 4.6 markers for each A-genome chromosome, were chosen to assess the genetic diversity of 109 accessions. These included 106 G. arboreum landraces, collected from 18 provinces throughout four Asiatic cotton-growing regions in China. A total of 128 alleles were detected, with an average of 2.13 alleles per locus. The largest number of alleles, as well as the maximum number of polymorphic loci, was detected in the A03 linkage group. No polymorphic alleles were detected on chromosome 10. The polymorphism information content for the 22 polymorphic microsatellite loci varied from 0.52 to 0.98, with an average of 0.89. Genetic diversity analysis revealed that the landraces in the Southern region had more genetic variability than those from the other two regions, and no significant difference was detected between landraces in the Yangtze and the Yellow River Valley regions. These findings are consistent with the history of sinense introduction, with the Southern region being the presumed center of origin for Chinese Asiatic cotton, and with subsequent northeastward extension to the Yangtze and Yellow River Valleys. Cluster analysis, based on simple sequence repeat data for 60 microsatellite loci, clearly differentiated Vietnamese and G. herbaceum landraces from the sinense landrace. No relationship between inter-variety similarity and geographical ecological region was observed. The present findings indicate that the Southern region landraces may have been directly introduced into the provinces in the middle and lower Yangtze River Valley, where Asiatic cotton was most extensively grown, and further race sinense crops were subsequently produced. (Managing editor: Ya-Qin Han) [source] HYDROLOGICAL EFFECTS OF AN UNCONTROLLED FLOWING WELL, RED RIVER VALLEY, NORTH DAKOTA, USA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2004Philip J. Gerla ABSTRACT: In areas of the Red River Valley that overlie permeable Paleozoic sediments, wetlands and salinization have developed where unregulated flowing wells discharge brackish water. Field data were collected to assess the fate of water and salt from a well 25 km northwest of Grand Forks. Drilled during the drought of the 1930s, discharge was used to replenish water in a small oxbow pond used by livestock. The unregulated well discharges about 56 m3/day, measured since 1993. This discharge exceeds ground water flow from the site, thereby forming a ground water mound with a maximum height of 1 m and a diameter of about 300 m. Most soil and underlying sediments near the well have a hydraulic conductivity of 0.3 m3/day. Flow net analysis suggests that less than 25 percent infiltrates, with the remaining water lost to surface flow and evapotranspiration (ET). Evapotranspiration and slow infiltration has led to increased salinization, with shallow soils exhibiting EC to 500 milliSiemens/m. The most pronounced soil salinization occurs along the margins of the oxbow pond and meander scars. Wetland vegetation with low diversity comprises three zones, with species associations similar to those of closed basin prairie potholes to the west. [source] WATER EXCHANGES: TOOLS TO BEAT EL NIÑO CLIMATE VARIABILITY IN IRRIGATED AGRICULTURE,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2004Michael J. Scott ABSTRACT: Using a case study of the Yakima River Valley in Washington State, this paper shows that relatively simple tools can be used to forecast the impact of the El Niño phenomenon on water supplies to irrigated agriculture, that this information could be used to estimate the significantly shifted probability distribution of water shortages in irrigated agriculture during El Niño episodes, and that these shifted probabilities can be used to estimate the value of exchanges of water between crops to relieve some of the adverse consequences of such shortages under western water law. Further, recently devised water-trading tools, while not completely free under western water law to respond to forecasted El Niño episodes (ocean circulation patterns), are currently being employed during declared drought to reduce the devastating effects of water shortages in junior water districts on high valued perennial crops. Additional institutional flexibility is needed to take full advantage of climate forecasting, but even current tools clearly could prove useful in controlling the effects of climate variability in irrigated agriculture. Analysis shows the significant benefit of temporarily transferring or renting water rights from low-value to high-value crops, based on El Niño forecasts. [source] Environmental state of Lake Kariba and Zambezi River Valley: Lessons learned and not learnedLAKES & RESERVOIRS: RESEARCH AND MANAGEMENT, Issue 3 2010C. H. D. Magadza Abstract Lake Kariba, still the largest reservoir in the world by volume, is 60 years old. It has undergone changes in its thermal properties, associated with global warming, which reflect in turn on its limnology. These changes include a shallower eipilimnion, higher heat content and increased tropicality to near equatorial status. The role of Lake Kariba with regard to its energy characteristics is discussed in light of global warming findings. The lake's water residence time has increased from 3.7 years to ,5.7 years, attributable to a reduced inflow from the Zambezi River. The phytoplankton communities have changed towards a cyanophyceae-dominated community, leading to a decline in entomostracan zooplankton, and a near collapse of the planktivorous Limnothrissa miodon fishery. Prolonged use of pesticides to control Glossina has led to measurable ecosystem level impacts on both terrestrial and aquatic biota. The impacts of the forced relocation of the Tonga people were still evident during this study. Siltation from resettlement areas has led to the loss of habitat and biodiversity in the inflowing streams to the lake. Unplanned shoreline development in the early history of the lake poses health problems. It is projected that global warming will cause the lake temperature to rise by ,4 °C by the end of the century. Higher temperatures will be accompanied by windier conditions, thereby enhancing the risks from storms on the lake. The appropriateness of administrative structures intended to manage the Zambezi River Basin environment also is discussed herein. It is concluded that the management protocol is institutionally a non-inclusive process lacking the capacity to involve other stakeholders in managing the lake's resources, and even less so in the integrated management of the basin. [source] Foraging in the Tennessee River Valley by Kandace HollenbachAMERICAN ANTHROPOLOGIST, Issue 2 2010Cheryl Claassen No abstract is available for this article. [source] Investigating cultural heterogeneity in San Pedro de Atacama, northern Chile, through biogeochemistry and bioarchaeologyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009Kelly J. Knudson Abstract Individuals living in the San Pedro de Atacama oases and the neighboring upper Loa River Valley of northern Chile experienced the collapse of an influential foreign polity, environmental decline, and the appearance of a culturally distinct group during the Late Intermediate Period (ca. AD 1,100,1,400). We investigate cultural heterogeneity at the Loa site of Caspana through analyses of strontium and oxygen isotopes, cranial modification styles, and mortuary behavior, integrating biological aspects of identity, particularly geographic origins, with cultural aspects of identity manifested in body modification and mortuary behavior. We test the hypothesis that the Caspana population (n = 66) represents a migrant group, as supported by archeological and ethnographic evidence, rather than a culturally distinct local group. For Caspana archeological human tooth enamel, mean 87Sr/86Sr = 0.70771 ± 0.00038 (1,, n = 30) and mean ,18Oc(V-PDB) = ,3.9 ± 0.6, (1,, n = 16); these isotopic data suggest that only one individual lived outside the region. Material culture suggests that the individuals buried at Caspana shared some cultural affinity with the San Pedro oases while maintaining distinct cultural traditions. Finally, cranial modification data show high frequencies of head shaping [92.4% (n = 61/65)] and an overwhelming preference for annular modification [75.4% (n = 46/61)], contrasting sharply with practices in the San Pedro area. Based on multiple lines of evidence, we argue that, rather than representing a group of altiplano migrants, the Caspana population existed in the region for some time. However, cranial modification styles and mortuary behavior that are markedly distinct from patterns in surrounding areas raise the possibility of cultural heterogeneity and cultural fissioning. Am J Phys Anthropol, 2009. © 2008 Wiley-Liss, Inc. [source] Genetic Diversity of Landraces in Gossypium arboreum L. Race sinense Assessed with Simple Sequence Repeat MarkersJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 9 2006Wang-Zhen Guo Abstract Asiatic cotton (Gossypium arboreum L.) is an "Old World" cultivated cotton species, the sinense race of which is planted extensively in China. This species is still used in the current tetraploid cotton breeding program as an elite germplasm line, and is also used as a model for genomic research in Gossypium. In the present study, 60 cotton microsatellite markers, averaging 4.6 markers for each A-genome chromosome, were chosen to assess the genetic diversity of 109 accessions. These included 106 G. arboreum landraces, collected from 18 provinces throughout four Asiatic cotton-growing regions in China. A total of 128 alleles were detected, with an average of 2.13 alleles per locus. The largest number of alleles, as well as the maximum number of polymorphic loci, was detected in the A03 linkage group. No polymorphic alleles were detected on chromosome 10. The polymorphism information content for the 22 polymorphic microsatellite loci varied from 0.52 to 0.98, with an average of 0.89. Genetic diversity analysis revealed that the landraces in the Southern region had more genetic variability than those from the other two regions, and no significant difference was detected between landraces in the Yangtze and the Yellow River Valley regions. These findings are consistent with the history of sinense introduction, with the Southern region being the presumed center of origin for Chinese Asiatic cotton, and with subsequent northeastward extension to the Yangtze and Yellow River Valleys. Cluster analysis, based on simple sequence repeat data for 60 microsatellite loci, clearly differentiated Vietnamese and G. herbaceum landraces from the sinense landrace. No relationship between inter-variety similarity and geographical ecological region was observed. The present findings indicate that the Southern region landraces may have been directly introduced into the provinces in the middle and lower Yangtze River Valley, where Asiatic cotton was most extensively grown, and further race sinense crops were subsequently produced. (Managing editor: Ya-Qin Han) [source] Geomorphic and sedimentological signature of a two-phase outburst ,ood from moraine-dammed Queen Bess Lake, British Columbia, CanadaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 1 2005Jane A. Kershaw Abstract On 12 August 1997, the lower part of Diadem Glacier in the southern Coast Mountains of British Columbia fell into Queen Bess Lake and produced a train of large waves. The waves overtopped the broad end moraine at the east end of the lake and ,ooded the valley of the west fork of Nostetuko River. The displacement waves also incised the out,ow channel across the moraine. Stratigraphic and sedimentologic evidence supports the conclusion that the ,ood had two phases, one related to wave overtopping and a second to breach formation. Empirical equations were used to calculate the peak discharge of the ,ood at various points along the west fork of the Nostetuko valley and to describe the attenuation of the ,ood wave. The velocity of the ,ood was also calculated to determine the time it took for the ,ood to reach the main fork of Nostetuko River. The highest peak discharges were achieved in the upper reach of the valley during the displacement phase of the ,ood. Peak discharge declined rapidly just below the moraine dam, with little change thereafter for approximately 7 km. Empirical formulae and boulder measurements indicate a rise in peak discharge in the lower part of the west fork valley. We suggest that ,ow in the upper part of the valley records the passage of two separate ,ood peaks and that the rise in discharge in the lower part of the valley is due to amalgamation of the wave and breach peaks. Hydraulic ponding in con,ned reaches of the valley extended the duration of the ,ood. In addition, erosion of vegetation and sediment in the channel and valley sides may also have exerted an in,uence on the duration and nature of ,ooding. Sediments were deposited both upstream and downstream of channel constrictions and on a large fan extending out into the trunk Nostetuko River valley. This study extends our understanding of the variety and complexity of outburst ,oods from naturally dammed lakes. It also shows that simple empirical and other models for estimating peak discharges of outburst ,oods are likely to yield erroneous results. Copyright © 2005 John Wiley & Sons, Ltd. [source] Geckos as indicators of mining pollutionENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2006Dean E. Fletcher Abstract Catastrophic collapse of a mine tailings dam released several million cubic meters of toxic mud and acidic water into the Guadiamar River valley, southern Spain, in 1998. Remediation efforts removed most of the sludge from the floodplain, but contamination persists. Clean-up activities also produced clouds of aerosolized materials that further contaminated the surrounding landscape. Whole-body concentrations of 21 elements in the Moorish wall gecko, Tarentola mauritanica, a common inhabitant of both rural and urban areas, were compared among seven locations. Locations spanned an expected contamination gradient and included a rural and an urban non,mine-affected location, two mine-affected towns, and three locations on the contaminated floodplain. Multivariate analyses of whole-body concentrations identified pollutants that increased across the expected contamination gradient, a trend particularly evident for As, Pb, and Cd. Additionally, higher contaminant concentrations occurred in prey items eaten by geckos from mine-affected areas. Comparison of element concentrations in tails and whole bodies suggests that tail clips are a viable nondestructive index of contaminant accumulation. Our results indicate that areas polluted by the mine continue to experience contamination of the terrestrial food chain. Where abundant, geckos represent useful taxa to study the bioavailability of some hazardous pollutants. [source] The hidden record: Late Holocene landscapes and settlement archaeology in the Lower Ohio River ValleyGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 2 2002C. Russell Stafford From extensive backhoe trenching and coring in the Great Miami,Ohio River confluence region, in conjunction with a large suite of radiocarbon ages, we have identified large tracts of late Holocene alluvium. Thick blankets of Historic alluvium (post-settlement) may also cover levees of the Ohio River. In conjunction with other studies in the Outer Bluegrass Region of the lower Ohio River valley, it is possible to document an association between floodplain Mollisols, Inceptisols, and Entisols and late Holocene-aged landforms. Levees appear to have stabilized between 1000 and 2000 yr B.P. Although buried soils are rare, archaeological materials were ubiquitous in late Holocene Landform Sediment Assemblages. Because a substantial volume of valley fill is late Holocene in age, Woodland sites of all types are frequently buried, and Fort Ancient sites may be buried by Historic alluvium. Therefore, if Woodland or later settlement studies in this region are based on surface evidence alone, they are likely to be biased. © 2002 John Wiley & Sons, Inc. [source] Geomorphic controls and transition zones in the lower Sabine RiverHYDROLOGICAL PROCESSES, Issue 14 2008Jonathan D. Phillips Abstract Instream flow science and management requires identification of characteristic hydrological, ecological, and geomorphological attributes of stream reaches. This study approaches this problem by identifying geomorphic transition zones along the lower Sabine River, Texas and Louisiana. Boundaries were delineated along the lower Sabine River valley based on surficial geology, valley width, valley confinement, network characteristics (divergent versus convergent), sinuousity, slope, paleomeanders, and point bars. The coincidence of multiple boundaries reveals five key transition zones separating six reaches of distinct hydrological and geomorphological characteristics. Geologic controls and gross valley morphology play a major role as geomorphic controls, as does an upstream-to-downstream gradient in the importance of pulsed dam releases, and a down-to-upstream gradient in coastal backwater effects. Geomorphic history, both in the sense of the legacy of Quaternary sea level changes, and the effects of specific events such as avulsions and captures, are also critical. The transition zones delineate reaches with distinct hydrological characteristics in terms of the relative importance of dam releases and coastal backwater effects, single versus multi-channel flow patterns, frequency of overbank flow, and channel-floodplain connectivity. The transitional areas also represent sensitive zones which can be expected to be bellwethers in terms of responses to future environmental changes. Copyright © 2007 John Wiley & Sons, Ltd. [source] Movement characteristics of the Scarce Blue-tailed Damselfly, Ischnura pumilioINSECT CONSERVATION AND DIVERSITY, Issue 1 2010KATHERINE A. ALLEN Abstract., 1. The Scarce Blue-tailed Damselfly, Ischnura pumilio, is threatened in the UK and exists in small, transient colonies. Consequently, little is known about its dispersal characteristics. This study investigates movement in two contrasting habitats with the aim of informing conservation management on a landscape scale. 2. Mark-release-recapture studies were performed at an established colony in the New Forest and a smaller population in the Red River valley in southern England. A total of 2304 individuals was marked. 3. Ischnura pumilio was found to be exceptionally sedentary. Mean gross lifetime movement was 56 m and 43% of individuals moved <50 m in their lifetime. Movements over 150 m were very rare. Maximum lifetime movement was 1165 m. As such, I. pumilio is the most sedentary odonate studied in the UK to date. 4. Movement was inversely density dependent, which has important conservation implications if individuals attempt to emigrate from small populations because of low density. The presence of parasitic mites (Hydryphantes sp.) significantly increased movement distance. 5. Ischnura pumilio had a low dispersal probability compared to other damselflies. As the smallest British odonate, this is in keeping with the relationship between size and dispersal found across taxa. 6. Ischnura pumilio has been regarded as a ,wandering opportunist' due to its tendency to appear in locations far from known sites. However, this study suggests that long range movement rarely occurs from prime habitat that is maintained in an early successional stage. This has implications for the conservation of the species in the UK. [source] The Pliocene to Early Pleistocene marine to fluviatile succession of the Seuil du Cotentin basins (Armorican Massif, Normandy, France)JOURNAL OF QUATERNARY SCIENCE, Issue 3-4 2003Olivier Dugué Abstract Marine and fluvial Plio-Pleistocene deposits of the Seuil du Cotentin, western Normandy range in age from Late Pliocene to Early Pleistocene. They are preserved in small Cenozoic grabens and are divided into six new formations based on lithology, granulometry, sedimentary structures and associated fossils. The depositional environments of these formations change from marine to fluviatile and represent two transgression,regression cycles. This paper outlines the detailed stratigraphical relationships of the western Normandy Plio-Pleistocene succession and discusses its correlation with the adjacent eastern area in the Seine River valley (France), in Cornwall and in the southern North Sea basin (East Anglia, Belgium, The Netherlands). Copyright © 2003 John Wiley & Sons, Ltd. [source] Charity and self-help: Migrants' social networks and health care in the homeland (Respond to this article at http://www.therai.org.uk/at/debate)ANTHROPOLOGY TODAY, Issue 4 2010Abdoulaye Kane This article examines the delivery of healthcare by Haalpulaar immigrants' village association in France to their rural villages in Senegal. In the context of the neo-liberal reforms in Senegal, the Haalpulaar immigrants have been very active in funding community project in the health sector for their communities of origin left to fend for themselves by the State. Haalpulaar migrants associations like TAD (Thilogne Association Developpement) and Fuuta Santé are improving access to healthcare in the Senegal River valley through the remittances of biomedicine, medical equipment as well as the organization of annual health caravans with the participation of French health professionals and local partners. [source] Tilting neotectonics of the Guadiamar drainage basin, SW SpainEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2004Josep M. SalvanyArticle first published online: 23 DEC 200 Abstract The Guadiamar river ,ows from the southern Iberian Massif to the Guadalquivir foreland basin, SW Spain. Its drainage basin displays asymmetries in the stream network, the arrangement of alluvial terraces and the con,guration of the trunk river valley. The stream network asymmetry was studied using morphometric measures of transverse topographic sym-metry, asymmetry factor and drainage basin shape. The alluvial terraces were studied through the lithologic logs of more than a hundred boreholes and ,eld mapping. The morphometric methods demonstrate a regional tectonic tilting toward the SSE, causing both the migration of the Guadiamar river toward the east and the migration of the Guadiamar tributaries toward the southwest. As a consequence of the Guadiamar river migration, an asymmetric valley developed, with a steep eastern margin caused by river dissection, and a gentle western margin where the main alluvial deposits are found. The ages obtained using the 14C analysis of samples from several alluvial deposits show that the river migration, and thus tilting, has occurred during the Holocene as well as earlier in the Quaternary. This interpretation revises the Guadiamar longitudinal fault assumed by previous studies. Copyright © 2003 John Wiley & Sons, Ltd. [source] Prediction of the behaviour of landslide dams using a geomorphological dimensionless indexEARTH SURFACE PROCESSES AND LANDFORMS, Issue 1 2003L. Ermini Abstract Landslide dams are a common phenomenon. They form when a landslide reaches the bottom of a river valley causing a blockage. The first effect of such a dam is the infilling of a lake that inundates the areas upstream, while the possibility of a sudden dam collapse, with a rapid release of the impounded waters, poses a higher flood risk to the downstream areas. The results of the main inventories carried out to date on landslide dams, have been examined to determine criteria for forecasting landslide dam evolution with particular emphasis on the assessment of dam stability. Not all landslides result in the blockage of a river channel. This only occurs with ones that can move a large amount of material with moderate or high-velocities. In most cases, these landslides are triggered by rainfall events or high magnitude earthquakes. A relationship also exists between the volume of the displaced material and the landslide dam stability. Several authors have proposed that landslide dam behaviour can be forecast by defining various geomorphological indexes, that result from the combination of variables identifying both the dam and the dammed river channel. Further developments of this geomorphological approach are presented in this paper by the definition of a dimensionless blockage index. Starting with an analysis of 84 episodes selected worldwide, it proved to be a useful tool for making accurate predictions concerning the fate of a landslide dam. Copyright © 2002 John Wiley & Sons, Ltd. [source] Fossil fruits of Salsola L. s.l. and Halanthium K.Koch (Chenopodiaceae) from Lower Pleistocene lacustrine sediments in Armenia,FEDDES REPERTORIUM, Issue 3-4 2008Janna Akopian Dr. For the first time imprints of fossil fruits of Salsola L. s.l. and Halanthium K.Koch (Chenopodiaceae, Salsoloideae,) are reported from the territory of Armenia, the latter being the first fossil record of the Southwest Asian genus worldwide. They were collected from fluvio-lacustrine diatomite layers of the Lower Pleistocene (Sisian series) in the upper-middle Vorotan river valley recently dated at 1.4,0.935 my (Early Pleistocene). The fossils are described, figured and compared with recent relatives. Due to poor preservation, the identity of the Salsola fruit cannot be specified but the similar genus Kochia can be excluded. The Halanthium fruit seems to differ from those of extant species. Both are also discussed in the context of the very poor fossil Salsoloideae record and of the actual and lower Pleistocene vegetation and environment. The findings of truly semidesert species underline the presence of open landscapes and extremely semiarid to arid conditions. However, stratigraphically more refined analyses are needed to draw conclusions about the former vegetation and the duration of arid periods because most macrofossils reported from the same strata indicate semiarid and even humid environments. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Fossile Früchte von Salsola L. und Halanthium K.Koch (Chenopodiaceae) aus unterpleistozänen lakustrischen Sedimenten in Armenien Erstmals wird über Funde fossiler Früchte der Gattungen Salsola L. s.l. und Halanthium K.Koch (Chenopodiaceae, Salsoloideae) aus Armenien berichtet. Für die letztere Gattung handelt es sich weltweit um einen Erstfund. Die nur mäßig guten Abdrucke stammen aus fluvio-lakustrischen Diatomiten der Sisian Serie vom oberen Vorotan-Tal, die nach neuesten Datierungen 1,4,0,935 Millionen Jahre alt sind und damit in das Unterpleistozän gehören. Die Fossilien werden beschrieben, abgebildet und mit den nächsten rezenten Verwandten verglichen. Während bei der Salsola -Frucht wegen Beschädigungen vor der Einbettung keine Artbestimmung möglich ist, die Zugehörigkeit zu Kochia aber ausgeschlossen werden kann, stimmt die besser erhaltene Halanthium- Frucht mit keiner rezenten Art überein. Beide Arten werden im Zusammenhang mit dem bisher äußerst spärlichen Fossilbefund und im Hinblick auf ihren möglichen ökologischen und vegetationskundlichen Indikatorwert diskutiert. Die Nachweise dieser Halbwüstenpflanzen sprechen für eine waldfreie Umgebung und ein extremsemiarides oder arides Klima zur Zeit der Einbettung. Die gleichen Schichten enthalten aber vor allem Makrofossilien mesophytischer Gehölze, die an ein semiarides bis humides Klima gebunden sind. Weitergehende Rückschlüsse sind erst dann möglich, wenn eine feinstratigraphische Analyse vorliegt, durch die größere klimatische Fluktuationen nachgewiesen werden könnten. [source] Archaeological site distribution by geomorphic setting in the southern lower Cuyahoga River Valley, northeastern Ohio: Initial observations from a GIS databaseGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 8 2004Andrew Bauer In this study, we compiled unpublished archival documentation of archaeological site locations from the southern part of the Cuyahoga River Valley in northeastern Ohio, USA, registered at the State of Ohio Historic Preservation Office into a Geographic Information Systems (GIS) database. Using digitized soil shapefiles to generate a geomorphic data layer, we assessed the spatial and temporal distribution of 79 known archaeological sites by landform association. This digital compilation indicates that Woodland period, Late Prehistoric, and Historic sites occur in most geomorphic settings along the river valley. In contrast, Paleoindian and Archaic sites only occur on Wisconsinan cut terraces and in upland interfluve settings, indicating that most of these documented sites are in primary contexts and have not been reworked. We discuss the distribution of archaeological sites in the study region as a function of various factors, including cultural activities, taphonomic processes, landform development, and the nature and extent of the original archaeological surveys. Observed spatial patterns of known sites clearly reflect local geomorphological controls; artifactual contexts from the earlier prehistoric periods are underrepresented in the database. We conclude that additional site surveys, as well as the excavation and documentation of new sites in this part of Ohio, are required to understand local prehistoric economies and to ascertain patterns of culturally mediated land use. © 2004 Wiley Periodicals, Inc. [source] | |||||||||||||||||||