River Valley Floor Research Articles

Application of geomorphons for analysing changes in the morphology of a proglacial valley (case study: The Scott River, SW Svalbard)

The progressive degradation of the cryosphere of High-Arctic areas causes an increase in the dynamics of geomorphic processes that shape the valleys of rapidly retreating glaciers. Those especially sensitive to global environmental changes are the small, land-ending valley glaciers that are in the phase of strong retreat. Under these conditions, the river valley's floors that are drained by proglacial waters are constantly undergoing intensive changes. For the analysis of these changes, two methods were used simultaneously (as a synthesis) to allow for quantitative and qualitative evaluation. The first one is the increasingly more common DoD method (DEM of difference), which allows quantifying volumetric changes as a result of topographic differentiation. The second one, which was applied for the first time on a small-valley spatial scale, is the geomorphons method that makes it possible to assess the stability of landforms and to determine the directions of their new development. To judge the applicability (advantages and disadvantages) of both methods for analysis of geomorphic changes in rapidly changing proglacial environments, the study was carried out over a 3.3 km distance of the non-glaciated section of the Scott River valley course (NW Wedel-Jarlsberg Land, SW Svalbard). This area (1.3 km2) is currently shaped by a braided gravel-bed river. More accurately, the study focused on the section spanning from the glacier terminus, which is the source of the Scott River, to its outlet at the Rechersche Fjord (Bellsundfiorden). The foundation for the development of comparative elevation models was a collection of terrestrial laser scanning (TLS) surveys that were taken with a Leica ScanStation C10 scanner during the 2010 and 2013 snowmelt seasons. On the basis of these surveys and with the use of TIN interpolation, high-resolution (0.2 m) digital terrain models (DTMs) were generated. The DTM models that had been prepared in this manner were used for the analysis of surface changes by employing Geomorphic Change Detection (GCD) software, and by simultaneously generating geomorphons maps for four selected test areas that covered characteristic fragments of the valley bottom (1- on the close forefield of the Scott Glacier terminus; 2- in the immediate vicinity of the narrow valley outlet at the foot of the marginal moraine ridge; 3- in the enlargement of the central section of the non-glaciated valley floor; 4- within the alluvial fan (outlet to the fjord)). A comparison of the obtained results (DoD and geomorphons maps; zonal statistics) as well as a compilation of both the quantitative assessment of the scale of changes and the qualitative assessment of the transformation's direction allowed for reconstructing the range and rate of three-year-long changes in morphology at the analysed sections of the valley floor. It was found that the pattern and rate of changes were closely related to the location of the test areas in the Scott River's catchment system. Significant differences in the dynamics of processes shaping the valley landforms along the longitudinal valley course were found.

Cretaceous and late Cenozoic uplift of a Variscan Massif: The case of the French Massif Central studied through low-temperature thermochronometry

Abstract Located in the foreland domain of the Alpine and Pyrenean mountain belts, the French Massif Central presents enigmatic topographic features—reaching elevations of ∼1700 m above sea level and ∼1000 m of relief—that did not originate from Alpine compressional nor from extensional tectonics. Similar to other Variscan domains in Europe, such as the Bohemian, Rhenish, and Vosges/Black Forest Massifs, a Cenozoic uplift has been postulated, although its timing and quantification remain largely unconstrained. With respect to the other Variscan Massifs, the French Massif Central is wider and higher and shows a more intense late Cenozoic volcanism, suggesting that deep-seated processes have been more intense. In this study, apatite fission-track and (U-Th)/He thermochronometry were applied to investigate the long-term topographic evolution of the Massif Central. Our new thermochronological data come from the eastern flank of the massif, where sampling profiles ran from the high-elevation region down to the Rhône River valley floor with a total elevation profile of 1200 m. Age-elevation relationships, mean track-length distributions, and thermal modeling indicate a two-step cooling history: (1) a first exhumation event, already detected through previously published thermochronology data, with an onset time during the Cretaceous, and (2) a more recent Cenozoic phase that is resolved from our data, with a likely post-Eocene onset. This second erosional event is associated with relief formation and valley incision possibly induced by a long-wavelength domal uplift supported by mantle upwelling.

An Intensive Archeological Survey of the Owl Hills-Tunstill 138-KV Transmission Line Route

Oncor Electric Delivery Company, LLC (Oncor) is planning to construct the Owl Hills—Tunstill 138-kV Transmission Line Route in Culberson, Reeves and Loving Counties, Texas. Oncor contracted with Halff Associates, Inc. to conduct an intensive pedestrian survey of 18.5 miles of new 138-kV transmission line on private property. The survey was conducted January 20-24, 2020 and a total of 102 shovel tests were excavated in areas where buried archeological deposits where expected, and two 15-meter (32.8-foot) transects underwent pedestrian survey within the 70-foot (21.3-meter) wide survey corridor, which measures approximately 157 acres. Three archeological sites (41RV208, 41RV209 and 41RV213) were identified and recorded during the archeological survey. Site 41RV208 is a prehistoric occupation containing a surface deposit of 12 lithic debitage, 6 flake tools, 6 cores, 2 groundstone fragments and 40 fire cracked rocks (FCR). The site is situated on a gravelly and deflated upland that forms the western rim of the Pecos River valley. Site 41RV209 consists of a prehistoric occupation containing a surface deposit of 12 FCR, 6 lithic debitage, 3 flake tools, 2 cores, 1 uniface, and 1 biface. This site is situated on the heavily eroded west bank of Salt Creek and has been disturbed by construction activities associated with an adjacent pipeline corridor. Site 41RV213 is an abandoned section of the Atchison, Topeka & Santa Fe (ATSF) Railway that parallels U.S. Highway 285 to the east. The section of railroad in the surveyed area has undergone extensive disturbance and consists of a narrow linear piling of fill, railroad gravels and non-descript metal debris. It is Halff’s recommendation that sites 41RV208, 41RV209 and 41RV213 are ineligible for National Register of Historic Places consideration in the surveyed area and no further cultural resources investigations are warranted for the project. While shovel testing within the lower terraces of the Pecos River valley floor resulted in negative findings, most of the shovel tests in this area did not encounter restrictive deposits soil or geologic deposits that antedate the Holocene. Therefore, the installation of the transmission line poles located along the lower alluvial terraces of the Pecos River was recommended for archeological monitoring. Halff recommends that construction of the remainder of the proposed transmission line route be allowed to proceed and that no additional archaeological investigations are recommended outside of the monitoring area. However, if the proposed transmission line route alignment changes, additional archeological survey may be necessary. In addition, should any cultural resources be discovered during the construction or maintenance activities associated with the project, work in the immediate area shall cease and the Texas Historical Commission be notified of the discovery.

Historical Reconstruction of the Scarcely Recognized Metallurgical Activity in Poland

Ironworks were located in the river valley floors as the water was the source of energy for the metallurgical technology. Trees growing in river valleys were a source of wood for charcoal production. Over the past centuries, ferrous metallurgy contributed to the transformation of the valley floor relief. Also the structure of the sediments was transformed. The subject of historical water-powered metallurgy in Poland is a poorly researched area from the perspective of natural sciences. The main research aim of this project, is a historical reconstruction of the scarcely recognized metallurgical activity, based on geomorphological, sedimentological and palaeobotnical changes in the environment. The project has two components complementary to each other. First part involves desk-based research during which digital data from air laser scanning is processed to determine the occurrence and distribution of potential forms related to the historical metallurgy, and an analysis of historical sources will be undertaken. In the next step, first fieldwork, and then the preparation of samples for radiocarbon and anthracological analysis will follow. During the fieldwork part, research will be carried out on an area of chosen river basins of the southern and central Poland. The research will be based on the geomorphological analysis in the places where potential or identified metallurgical centers were placed, along with the excavation of deposits and sampling for further analysis, both in the charcoal kilns and the former smelter ponds. If it proves possible, it is planned to expose the deposits in the weirs. Preliminary research contradicts the low invasiveness of historical metallurgy in the environment. According to the preliminary studies of the authors, it is known that in studied river valleys and adjacent areas, traces of former charcoal kilns have been found at a large scale (tens of thousands of forms). DEM images generated from airborne LiDAR data allow simple and relatively quick identification and inventory of the remnants past charcoal production. The large number of charcoal kilns, and the vast area they cover, indicate that the past charcoal production has had a significant impact on the environment of studied area. Analysis of the species composition of charcoals collected from kilns has shown the presence of pine wood mainly. Also the unexpected results of the first radioisotopic charcoals dating from the charcoal kilns, with dates of the twelfth and thirteenth centuries, provide a particularly strong motivation for examining more forms in order to find equally spectacular results and to confirm a new perception of the beginning of water-powered metallurgy in Poland.

Probable Deep Erosion by Continental Ice Sheet Melt Water Floods: Chalk Buttes Area of Carter County, Montana, USA

Topographic maps are used to determine erosional landform origins along the Little Missouri River-Powder River drainage divide in the Chalk Buttes areas of Carter County, Montana. Asymmetric drainage divides, drainage divide gaps, and isolated erosional remnants are used to determine a sequence of erosion events beginning with headward erosion of northeast-oriented Little Missouri River tributary valleys and ending with headward erosion of the deeper north-northeast and north-northwest oriented Powder River valley. Gaps notched into present day drainage divides and orientations of valley heads on either side of those gaps suggest many closely spaced southeast-oriented streams flowed across the region immediately prior to being captured by headward erosion of deeper north-oriented valleys. Buttes capped by horizontal Miocene Arikaree sandstones stand 500 feet (152 meters) or more above surrounding Little Missouri River tributary drainage basin elevations while the Powder River valley floor elevation is as much as 800 feet (244 meters) below those surrounding elevations. A water source could not be determined from the map evidence, however the study area is located to the south and west of a known continental ice sheet margin and large southeast-oriented ice-marginal melt water floods should have logically crossed the region.

Physical and geographical principles of tourist cluster’s formation in Kharkiv region

Formulation of the problem. The article considers the main physical and geographical factors (climate, water, forest, relief) forming a tourist cluster on the territory of Kharkiv region. The cluster approach allows us to determine priority directions for the development of tourism, to use natural conditions as much as possible and to carry out nature conservation measures.The purpose of the article. The purpose of this article is to study natural-geographical criteria for the formation of the tourist cluster in Kharkiv region, their evaluation and generalization.Methods. The study of climatic parameters has been carried out using a statistical method, analyzing time series of average monthly air temperature, precipitation and solar radiation for the period 2001-2015.Results. Given the fact that Kharkiv region is in the northeast of Ukraine, it is characterized by a peripheral location. In general, its area is approaching a circle, determining equivalent relations between the regional center and the outskirts.The relief of Kharkiv region is mostly undulated, it is a plain, cut by river valleys, valley floors and power ravines. The peculiarities of the terrain in the region are emphasized by burial mounds (graves) created by man in ancient times, which increases historical and cultural value of the region under study. Climatic resources of Kharkiv region are favorable for recreation, especially for summer types, such as beach, sports, cognitive recreation.According to N. Fomenko’s methodology of estimating the recreational territory, the climatic resources of the studied region correspond to the indicator good, as well as to the parameters of optimal climatic conditions for recreational purposes. The territory of Kharkiv region is located in two landscape zones - the forest-steppe (northern part of the region) and the steppe (southern part). Today steppe vegetation has almost disappeared, which is explained by excessive agricultural activity. Kharkiv region is one of the main centers of balneotherapy on the left bank of Ukraine.Scientific novelty and practical significance. Today, the tourist cluster is considered an innovative form of the regional economic development, since tourism is one of the territory’s socio-economic functioning factors. Tourist and recreational activities are also very important in international economic relations. The formation of the tourist cluster of the territory will make it possible to effectively use all available tourist and recreational resources of the territory. Thus, the main factors determining the organization of tourist and recreational activity on the territory of Kharkiv region are relief, climate, water and vegetation resources. The region under study has sufficient recreational and tourist resources and good potential for their development, primarily of cognitive, river recreational, green and ecological tourism.

The morphology of the Luciąża River valley floor in the vicinity of the Rozprza medieval ring-fort in light of geophysical survey

Abstract Multidisciplinary research (including magnetic survey, earth resistance survey, geological mapping, detailed archaeological surface survey and geochemical prospection) was undertaken on an area of about 0.7–9.0 hectares (depending on the method) in the close surroundings of the medieval ring-fort relicts in central Poland. The geophysical studies of the vicinity of the Rozprza ring-fort were part of a multi-method complementary non-destructive archaeological survey. The ring-fort is situated in the Luciąża River (Vistula River basin) valley floor and the flood plain morphology is very important for the reconstruction of palaeoenvironmental conditions of settlement location. Results of aerial photographs and geophysical prospection allowed the discovery of traces of sub-fossil palaeomeanders of different sizes as well as relicts of archaeological features (system of ramparts and moats). It was possible due to the application of high resolution archaeo-geophysical surveys. Both natural structures and also anthropogenic features registered with geophysics have been verified by geological sounding. The surface geology structure of the close vicinity of the ring-fort has been recognised in detail and selected organic deposits of palaeochannel fills and overbank covers have been 14C dated. The Rozprza ring-fort was situated in a defensive location on the surface of a sandy terrace remnant in the central part of a (partly) swampy valley floor. The accumulation of recorded fills of palaeochannels and moats covers the whole Holocene, as documented by 14C data. It gives the possibility for future detailed palaeoenvironmental studies. The results of geophysical studies, due to their known precise location, allow the effective planning of further research activities, both archaeological and palaeoenvironmental.

Middle Palaeolithic land use in Dutch and Belgian Limburg: Integrating data from surface sites

The European Middle Palaeolithic archaeological database is rich, but is biased towards evidence that originates in stratified sites. In many river catchments, prevalent and often ignored evidence for Middle Palaeolithic occupation is found in palimpsest lithic assemblages on the surface. By way of a case study, this paper addresses the problem of how to integrate lithic artifact assemblage data from such contexts to complement an often unbalanced picture of long-term land use. Analysis of a sample of Middle Palaeolithic surface assemblages from south–southwest facing edges of plateaus and terraces in Dutch and Belgian Limburg yields data suitable for comparison and integration with those from stratified assemblages associated with the wider Maas River valley floor. Sample size and artifact class diversity relationships account for sample size effects and numerically summarize patterns of inter-site fragmentation of core reduction sequences and differential artifact discard, arguably indicators of regional mobility and land use. Variability in artifact class diversity among assemblages also indicates differences in site occupational frequency. When viewed from a long-term diachronic perspective, integrated evidence from cumulative and spatial palimpsests suggests that land use behavior was complex, dynamic, and varied according to topographic factors in the research area. Lack of chronological resolution, variable site formation processes and conditions of artifact recovery complicate detailed interpretation of land use patterns. Despite these problems, results suggest that throughout the Middle Palaeolithic in the research area some plateau and terrace localities were ‘persistent places’ frequently re-occupied for a variety of purposes, while other similarly situated sites and localities more closely associated with river and stream valleys appear to have been occupied less frequently for a more limited range of activities.

Preserving the Legacy of Historic Metal-Mining Industries in Light of the Water Framework Directive and Future Environmental Change in Mainland Britain: Challenges for the Heritage Community

Contemporary global metal mining is a source of environmental pollution, but in Britain it is our historic mining industry that has left a legacy of contamination in the landscape, around both the immediate mine sites as well as within the river valley floors that drain these orefields. It has been estimated that the levels of lead and zinc stored within some northern British river systems represent values comparable to present-day reserves of economically viable ore deposits and exposure to them can be detrimental to human health. Despite the prevalence and significance of these deposits, they have been neglected by the cultural heritage community in favour of more easily interpretable remains such as mine buildings, technologies of ore procurement and processing, and the final products of manufacture. This paper argues that in light of future climate change and legislation associated with the European Union Water Framework Directive, heritage managers and industrial archaeologists have to start investigating these deposits as part of their studies and to engage with the environmental science and geomorphological communities who are, at present, setting the agenda in terms of strategies for pollution mitigation and landscape remediation.

Effect of relief and land use on heat stress in Kraków, Poland

Heat stress in urban areas is controlled mainly by the impact of anthropogenic land use on the active surface heat balance. This paper shows the role of land form superimposed on the land-use impact, using the example of Krakow, Poland. The city is located in a concave land form, on the Wisla (Vistula) River. The automatic measurements of air temperature and humidity were realised in Krakow from April to October, in the years 2010-2012. For the daytime conditions, ANOVA test and Tukey’s test showed significant differences in the number of very hot days and number of heat waves, between urban areas in the valley and rural areas, both in the valley and on the slope. For the nighttime, significant differences were found for the number of tropical nights, not only between urban and rural areas, but also between urban areas located in various landforms and between urban areas in the valley floor and rural areas located in various landforms. Both urban and rural measurement points located in the river valley floor experienced the highest numbers of very hot days, heat waves and extreme air temperature duration. For measurement points elevated about 50 m above the valley floor, the indices’ values were lower by about 50 %.

Prediction of the Vistula Channel Development Between Wloclawek and Torun: Evaluation with Regard to the New Geological Survey

Abstract The aim of this paper is to present the geological structure of the Vistula river valley floor as the modifying factor of fluvial processes and present the development conditions of the contemporary Vistula river channel, which underwent marked transformation due to bed erosion and lateral erosion below the Włocławek reservoir. The analysis of the geological data and the geological survey conducted at the study reach of the Vistula between Włocławek and Toruń resulted in an image of the geological structure of the channel bed along the longitudinal profile

Use of terrestrial laser scanning (TLS) for monitoring and modelling of geomorphic processes and phenomena at a small and medium spatial scale in Polar environment (Scott River — Spitsbergen)

The application of Terrestrial Laser Scanning (TLS) for precise modelling of land relief and quantitative estimation of spatial and temporal transformations can contribute to better understanding of catchment-forming processes. Experimental field measurements utilising the 3D laser scanning technology were carried out within the Scott River catchment located in the NW part of the Wedel Jarlsberg Land (Spitsbergen). The measurements concerned the glacier-free part of the Scott River valley floor with a length of 3.5km and width from 0.3 to 1.5km and were conducted with a state-of-the-art medium-range stationary laser scanner, a Leica Scan Station C10. A complex set of measurements of the valley floor were carried out from 86 measurement sites interrelated by the application of 82 common ‘target points’. During scanning, from 5 to 19 million measurements were performed at each of the sites, and a point-cloud constituting a ‘model space’ was obtained. By merging individual ‘model spaces’, a Digital Surface Model (DSM) of the Scott River valley was obtained, with a co-registration error not exceeding ±9mm. The accuracy of the model permitted precise measurements of dimensions of landforms of varied scales on the main valley floor and slopes and in selected sub-catchments. The analyses verified the efficiency of the measurement system in Polar meteorological conditions of Spitsbergen in mid-summer.

Geomorphologic map of the Biferno River valley floor system (Molise, Southern Italy)

A 1:20,000-scale geomorphologic map of the valley floor system of the Biferno River (Molise Region, Italy) is presented in this paper. Map analysis and aerial photography interpretation, in addition to field surveys, have allowed digital mapping of fluvial landforms and associated coastal, slope and anthropogenic forms which have characterised the valley floor in different periods. Comparative multi-temporal analysis performed in a GIS for the time-period 1869–2010 allowed the reconstruction of spatial-temporal relationships between most of the mapped landforms and acquisition of quantitative data on channel adjustments. The geomorphologic map provides an overall large-scale view of major channel adjustments over the past 150 years as well as the current morphological setting and dynamics of the Biferno valley floor. It provides a basic map for land planning policy with the observed distribution of active geomorphic processes to be used for landslide and erosion susceptibility assessment and the data obtained on channel adjustments essential in investigating land cover change over the same period. As the Biferno valley floor system is characteristic of major river systems in Central-Southern Italy, the reconstructed framework of valley floor transformations turns out to be useful when assessing a representative channel evolution model and potential scenarios concerning near future dynamics of similar river systems.

Delivering the Benefits of Aggregates Levy Sustainability Funded Research on River Valley Archaeological Sites in the Severn-Wye Catchment, UK

The recently published Mineral Extraction and Archaeology: A Practice Guide (English Heritage, 2008) identifies the use of geomorphological mapping and specialist remote sensing technologies allied to other techniques as important tools for use in the investigation of deeply buried archaeological sites. Such approaches are particularly valuable within environments like river valleys where prospection is particularly difficult due to the masking effect of alluvium; however, some of these techniques are unproven in several major river catchments where aggregate extraction is significant and they have yet to be widely integrated in commercial practice as part of the planning process. Methodological approaches using these techniques have largely been developed since 2002 through a number of research projects supported by the Aggregates Levy Sustainability Fund (ALSF) and English Heritage. They focus on enhancing understanding of the geoarchaeological and chronological development of river valley floors and thus the environment(s) within which archaeological sites have developed and are preserved. Light Detection and Ranging (LiDAR)-derived digital terrain modelling supported by information from other sources is used to map landform units (terraces, palaeochannels, terrace ‘islands’ and edges, etc.) within a Geographic Information System (GIS) framework.The high horizontal and vertical resolution of LiDAR allows microtopography to be mapped and this is often indicative of sub-surface geomorphological structures. In conjunction with historic environment record (HER) derived data this allows the macro- and micro-topography, relative chronology, and likely archaeological resource of key landform units to be modelled more accurately than has been previously possible. This enables areas of different archaeological potential to be highlighted, thus enabling more tightly focused, evidence-based evaluation and mitigation strategies to be developed. Other approaches such as specialist geophysical survey and, where organic material is sparse, the use of optically stimulated luminescence (OSL) dating can also be integrated to great effect to test the chronostratigraphic models produced.The use of this new ‘toolkit’ has a particularly high potential for application within large-scale, mineral extraction developments in river valleys, supporting the delivery of knowledge-based and proportionate projects at both pre- and post-determination stages as recommended in the minerals practice guide. This article focuses on a recent ALSF supported research project in the Lower Severn Valley which has tested the effectiveness of elements of the ‘toolkit’ within this major river catchment. This is accompanied by a case study of an evaluation undertaken in the Lugg Valley, a tributary of the River Wye in Herefordshire. This employed many of these techniques and provides one of the first examples of a commercially driven project where the considerable benefits of this approach to both archaeological curators and developers have been realized.

Airborne lidar intensity and geoarchaeological prospection in river valley floors

AbstractArchaeological applications of airborne lidar topographic data are now well known and documented in the academic literature. Rather less well explored by archaeologists are the potential of lidar intensity data. In this paper we explore the application of lidar intensity for geoarchaeological prospection in river valley floors. After briefly considering the context of archaeological remote sensing in river valleys, we examine some factors influencing the lidar intensity record and explore processing steps that may be required to effectively utilize intensity data, before reviewing the utility of intensity data for the geoarchaeological assessment of test sites in the Trent Valley of the English Midlands (UK). Results suggest that intensity imagery may assist greatly in the interpretation of airborne lidar topographic data and that its analysis contributes to a qualitative understanding of land cover and the burial environment of archaeological remains, either cultural or environmental; furthermore in some circumstances it is possible to identify anthropogenic archaeological cropmarks in intensity imagery. It is concluded that the standard methodology employed in using airborne lidar for archaeological survey should as a matter of course include the collection and analysis of intensity data. Copyright © 2011 John Wiley & Sons, Ltd.

Holocene Inset Fills of the Odra River in the Racibórz Basin

Holocene Inset Fills of the Odra River in the Racibórz Basin Geomorphic and lithological research conducted in the Odra River valley between Koźle and Krapkowice led to recognition of the postglacial development of the upper Odra River valley floor, for the first time, on the basis of a larger number of absolute datings. The formation of the inset alluvial fills by a meandering river started during the Early Holocene at the latest; however, the absence of a clearly developed system of large Late Vistulian palaeomeanders is notable within the analysed reach of the valley. Mid- and Late Holocene alluvial series were deposited by a river that exhibited a tendency to decrease in channel sizes. Nevertheless, large meanders were formed again in historical times. Oxbow fills in the Odra River valley are dominated by mineralogenic deposits. Their sedimentation can be correlated with the accretion of overbank and colluvial sheets in the valley floor. In the light of radiocarbon chronology, a relationship between Neolithic and subsequent phases of settlement in the catchment and the intensive deposition of these sediments cannot be ruled out.

Assessing CH4 and CO2 emissions from wetlands in the Drenthe Province, the Netherlands: a modelling approach

AbstractAssessment of land use related greenhouse gas (GHG) emissions on larger spatial scales is usually achieved by modelling. Surface flux measurements are expensive and measurement locations too widely scattered to serve as spatially reliable flux estimates. Here we assess CO2 and CH4 fluxes from wetland nature reserves in the Dutch province of Drenthe, using the PEATLAND-VU model. Since surface flux observations in the province are absent and cannot be obtained in a short (<1 year) time frame, we extrapolated model validation from elsewhere to the research area. In this way a cost-effective methodology is developed for landuse-related greenhouse gas emission assessments, which can be applied by local governments at a subnational scale.Nature development and restoration in the Netherlands involves usually the restoration of high water tables in former agricultural areas and extensivation or abandonment of agricultural activities. Wet peat soils are known to emit considerable quantities of CH4, while drained agricultural soils emit CO2 from decomposition of the soil organic matter. Therefore, these landuse changes may affect GHG emissions and an assessment of their effects is useful for environmental policy.The PEATLAND-VU Model was used to simulate the CH4 and CO2 emissions for the years 2005-2007 and for May/June 2008. Previous field validation of the model elsewhere was checked for local validity with CH4 and CO2 flux measurements in short field campaigns in May/June 2008, at two locations, Visvliet and Balloërveld. These sites represent respectively eutrophic and oligotrophic peat and peaty soils, and showed large differences in fluxes. These flux differences were simulated correctly by the model by adapting the vegetation net primary production and methane oxidation parameters. Next, model simulations were run for eight combinations of vegetation and soil type. Using the simulated fluxes and the areal extent of the soil combinations, a GIS-based upscaling over all nature reserves was made.This study shows that river valley floors with mesotrophic and eutrophic peat soils dominate the greenhouse fluxes of the area. CH4 fluxes are high in wet terrain, while the CO2 fluxes are high when water table is lower. The fluxes from oligotrophic peat soils are comparatively low. Nature development can contribute to a decrease of the total greenhouse gas flux from peat soils and to conservation of soil organic matter.

Holocene history of the River Seine, Paris, France: bio-chronostratigraphic and geomorphological evidence from the Quai-Branly

Bio-chronostratigraphic observations compiled from Quai-Branly in Paris (France) and their comparison with previous studies in the Paris Basin allow documentation of the morphodynamic evolution of the River Seine during the middle and late Holocene. This history begins in the Boreal (between 9500 and 8850 cal. BP), with the deposition of tufa, expressing a stabilized river bed. During the second part of the sub-Boreal the water-table was low. At the beginning of the sub-Atlantic (towards 2800/2700 cal. BP), alluvial dynamics increase, as is recorded elsewhere throughout the Paris Basin. At the beginning of the second part of the sub-Atlantic (around 2000 cal. BP), flood dynamics persisted at a lower intensity. Human occupation occurred from the fifth century AD. Before or around the beginning of the seventeenth century AD, a natural levee was built, indicating the progressive attachment of the Quai-Branly area to the floodplain. The hydrodynamic evolution of the River Seine observed at the Quai-Branly site is similar to that recorded in other river valley floors of the Paris Basin. This evolution appears to be in response to global climatic changes rather than to variations induced by human activities.

Evidence of Enhanced Atmospheric Ammoniacal Nitrogen in Hells Canyon National Recreation Area: Implications for Natural and Cultural Resources

Agriculture releases copious fertilizing pollutants to air sheds and waterways of the northwestern United States. To evaluate threats to natural resources and historic rock paintings in remote Hells Canyon, Oregon and Idaho, deposition of ammonia (NH3), nitrogen oxides (NOx), sulfur dioxide (SO2), and hydrogen sulfide (H2S) at five stations along 60 km of the Snake River valley floor were passively sampled from July 2002 through June 2003, and ozone data and particulate chemistry were obtained from the Interagency Monitoring of Protected Visual Environments (IMPROVE) station at Hells Canyon. NH3 concentrations were high; biweekly averages peaked at 5–19 ppb in spring and summer and the nutrient-laden Snake River is a likely source. Fine particulate ammonium nitrate (NH4NO3) averaged 2.6 µg/m3 during the 20% of worst visibility days with winter drainage of air masses from the Snake River Basin and possibly long distance transport from southern California. Other pollutants were within background ranges. NH3 is corrosive to clay-based picto-graphs; nitrogen deposition can alter natural biotic communities and terrestrial ecosystem processes at levels reported here.

Neogene gravity folds at the Yegor’evsk phosphorite deposit

At the Yegor’evsk phosphorite deposit, the beds lie horizontally, although peculiar folds are observable locally. Close to the present-day and Neogene river valleys, the phosphorite-bearing succession and the Lower Cretaceous beds acquire an appreciable tilt toward the river valley floor. Folds occur only in those places where the river valley downcuts Oxfordian clay to a considerable depth (down to 10 m or deeper). In such cases, the plastic clay is squeezed out under the load of overlying sediments into the valley wall and is removed with water. The overlying beds subside as a strip parallel to the river valley and make up a border that is folded down.