bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimente mit Ozon: Angewandte Chemilumineszenz
Authors: Albrecht Steffen , Brandl Herbert , Weiß Dieter , Zimmermann Thomas
Published: February 2007

Es werden drei sehr gut sichtbare experimentell erprobte Chemilumineszenz‐Demonstrationen bei Einsatz von Ozon als Oxidationsmittel vorgestellt. Die Experimente können auch in größeren Räumen bei nur mäßiger Verdunklung eindrucksvoll demonstriert werden. Es handelt sich um die Umsetzung des Ozons mit einem Phenazinfarbstoff, einem Luminophor und erstmals mit Ruthenium‐organyl‐Komplexen. Neben den Versuchsbeschreibungen wird soweit möglich auf den Reaktionsmechanismus eingegangen.
Ein antitumorwirksames Makrolacton
Authors: Feil Sylvia
Published: February 2007

Aus dem karibischen Feuerschwamm Tedania ignis wurde 1984 Tedanolid isoliert und seine Struktur bestimmt. Seither konnte der marine Naturstoff nicht in ausreichenden Mengen für weitere Untersuchungen gewonnen werden, weshalb nur bekannt ist, dass er in Maus‐Leukämie‐Zelllinien inhibierend aktiv ist. Jetzt stellt M. Kalesse von der Leibniz‐Universität Hannover die erste Totalsynthese vor.
Tarantel und Chili
Authors: Jaenicke Lothar
Published: February 2007

Von der sprichwörtlichen Tarantel gestochen zu werden, tut weh; Empfindliche mögen daraufhin vor Schmerz tanzen, Überempfindliche gar im anaphylaktischen Schock sterben. Dabei ist der Angriffsort der Toxine ein Ionenkanal, an dem auch das in Chili enthaltene Capsaicin seine Wirkung entfaltet.
Standbymodus für mRNA
Authors: Hille‐Rehfeld Annette
Published: February 2007

Die Proteinbiosynthese wird durch die Verfügbarkeit der mRNA als Bauanleitung für die Translation reguliert. Die Menge translatierbarer mRNA wird nicht nur durch die Transkriptionsaktivität und den Abbau durch RNasen kontrolliert, sondern auch durch räumliche Segregation.
Cadherin‐4 plays a role in the development of zebrafish cranial ganglia and lateral line system
Authors: Wilson Amy L. , Shen Yu‐Chi , Babb‐Clendenon S.G. , Rostedt Jason , Liu Bei , Barald Kate F. , Marrs James A. , Liu Qin
Published: February 2007

We previously reported that cadherin‐4 (also called R‐cadherin) was expressed by the majority of the developing zebrafish cranial and lateral line ganglia. Cadherin‐4 (Cdh4) function in the formation of these structures in zebrafish was studied using morpholino antisense technology. Differentiation of the cranial and lateral line ganglia and lateral line nerve and neuromasts of the cdh4 morphants was analyzed using multiple neural markers. We found that a subset of the morphant cranial and lateral line ganglia were disorganized, smaller, with reduced staining, and/or with altered shape compared to control embryos. Increased cell death in the morphant ganglia likely contributed to these defects. Moreover, cdh4 morphants had shorter lateral line nerves and a reduced number of neuromasts, which was likely caused by disrupted migration of the lateral line primordia. These results indicate that Cdh4 plays a role in the normal formation of the zebrafish lateral line system and a subset of the cranial ganglia. Developmental Dynamics 236:893–902, 2007. © 2007 Wiley‐Liss, Inc.
Agriculture and nature in ecological networks in the Netherlands and Europe
Authors: Horlings Ina , Gersie Jaap
Published: February 2007

In the last few decades, the area of land used for agriculture in the Netherlands has decreased, whereas agricultural production has steadily increased. One of the effects of this development has been a severe deterioration in the quality of the natural environment as agriculture and nature compete for space. Although attempts have been made to integrate agriculture and nature conservation, the policies adopted have not been wholly successful and environmental degradation has continued. Consequently, a new strategy for a National Ecological Network (NEN) has been developed. A number of factors are proposed which will determine the success, not only of the NEN in the Netherlands, but also of the proposed European Ecological Network (EECONET) in integrating the often conflicting goals of agriculture and nature conservation.
Towards practical environmental provision in Hungary
Authors: Reeves Alison
Published: February 2007

Environmental policy and management issues relating to the improvement of environmental protection are addressed and the conflicts between environmental protection and economic development within a new democracy highlighted. There is a realization that as Hungary moves from a developing to a developed capitalist nation, much ‘progress’ takes place with little honest regard for environmental assets. No clear image exists of the importance of sustainable development and the benefits of conserving natural resources. Continued environmental degradation, efforts towards EC harmonization and privatization of industries and businesses have all lead the Hungarian Government to formulate new environmental policies. The lack of a countrywide environmental monitoring programme means that informed decision‐making over the development of pollution abatement strategies is difficult. Economic reform lies in the commissioning of new ‘green’ technology which will accompany initiatives directly concerned with the promotion of the sciences, arts and the environment. Concerns in Western Europe over pollution and the befoulment of the global community are still incongruous to most Eastern Europeans, who live in relative poverty. New priorities in environmental protection are being established which should take the priorities of the Hungarian nationals into account.
Environmental constraints on the economic and social development of Small Islands
Authors: Perdicoúlis Anastássios , Power Shahed
Published: February 2007

The island of Syros in Greece is at the start of a major involvement in the tourist industry, while intensive agriculture is already being practised and a revival of its ship‐building industry is being negotiated. The development and maintenance of these and other activities is constrained by the natural resources on the island, such as land, water and energy, and by environmental degradation, the destruction of natural habitats and pollution. This paper outlines the present state of the environment and development on Syros and highlights specific environmental constraints to further economic and social development. The need for environmental resource management is emphasized, to co‐ordinate the efforts of the local authorities and individuals towards the achievement of a balanced level of resource utilization with prospects for sustainability.
Implementation of environmental policy using the eco‐management and audit scheme for UK local government: Experience in Cleveland
Authors: Counsell David , King Bob
Published: February 2007

Cleveland County Council's participation in the eco‐management and audit scheme pilot programme, its adoption of EMAS as a framework for implementing corporate environmental policy and its experience in introducing the scheme into units within the authority are outlined. Cleveland was one of seven local authorities involved in the pilot project for EMAS in UK local government and the scheme has now been adopted as a framework for implementing the County's environmental strategy. Action is proceeding both at the corporate level and within individual departments and units. A corporate overview and coordination system is in place and corporate action is being taken to address the direct environmental effects of energy and purchasing. A case study is included of the introduction of EMAS into the Department of Environment, Development and Transportation's Environment Division. The application of the EMAS framework to identify and tackle environmental effects is discussed. It is concluded that adoption of EMAS will improve environmental efficiency in the authority and help to promote good environmental performance in other sectors of the community.
Political evolution of EMAS: Perspectives from the EU, national governments and industrial groups
Authors: Franke Juergen
Published: February 2007

The adoption of the eco‐management and audit scheme (EMAS) in 1993 by the Council of Ministers was preceded by controversial debates. The European Commission presented EMAS in 1990 as a mandatory scheme. Industry responded in unison and rejected the compulsory nature of the scheme strongly. When the Commission decided to change the scheme into a voluntary standard, the response of industry became diverse. Industry in general welcomed EMAS as it saw it as a means to improve its image; German industry, however, continued to oppose the scheme. Its criticism was that the scheme did not take into account different emission standards which have to be achieved in different countries. Another important reason was that the management‐oriented scheme does not correspond well to the German approach to handling environmental problems. German companies are more technology‐oriented. An active advocate of EMAS was the UK. As the UK had taken the lead on environmental management systems and environmental auditing, it was keen to push these concepts throughout Europe.
Changes in an urban water resource, an example from Sydney, Australia
Authors: Warner R. F. , McLean E. J. , Pickup G.
Published: February 2007

This paper examines present and future resource utilization in the tidal section of the Georges River in the southern part of Sydney. Over the last 30 years, the physical characteristics of the river have changed as a result of urbanization, changed hydrologic regime and sand dredging. Urbanization has resulted in an increase in population from 190,000 in 1947 to 550,000. This has resulted in an increase in runoff, sediment input to the river and waste disposal. The change in hydrologic regime has resulted in a substantial increase in the magnitude and frequency of flooding which has increased erosion. Sand dredging has increased the channel capacity, enlarged the tidal prism and increased water turbidity. It has also resulted in extensive bank erosion in the upper part of the river and extensive deposition lower down as tailings are deposited. Although most of these changes have resulted in the deterioration of environmental quality, use of the river for recreation and as an urban amenity has increased.
Pseudo‐anticlines and other structures in some calcretes of Botswana and South Africa
Authors: Watts N. L.
Published: February 2007

Deformation structures, within some Quaternary calcretes of Botswana and South Africa, have been classified into five types. Type 1 folds are small‐scale (< 2 m wavelength) anticlines in shale or sheet calcrete, separated by wedges of calcrete, polygonal in plan. The anticlines have resulted from horizontal expansion and buckling caused by the disruptive growth of the calcrete wedges. Type 2(a) folds are medium‐scale, strongly convoluted features in sheet calcrete and bedrock and are attributed to the introduction of calcrete along major vertical joint planes. Type 2(b) folds are large wavelength (> 20 m), but low amplitude (< 1 m), anticlines in hardpan calcrete; structural evidence suggests dominantly horizontal compression within the hardpan due either to an overall increase in volume of the calcrete, or to the disruptive formation of calcrete in joints in the synclinal areas. The mineralogy of the calcretes is dominated by low‐Mg calcite which may have inverted from a high‐Mg form; the deformation in type 1 and 2 folds was probably caused by the disruptive and displacive growth of calcite during calcretization. Type 3 folds are saucer‐shaped depressions in hardpan calcrete and may be due to the removal of soluble salts below the folded layer during or after calcretization. Finally, type 4 folds are small, diapiric anticlines resulting from the upward injection of swelling clays into calcrete or calcretized shale.
Some experimental data on slopewash and wind action with reference to quaternary morphogenesis in Belgium
Authors: De Ploey J.
Published: February 2007

This paper discusses field observations, field measurements, field and laboratory experiments concerning the physical weathering and the erodibility of sandy Tertiary rocks and loess mantles in Belgium. The observed phenomena and the experimental data have been discussed in terms of soil mechanics. Special attention has been paid to crack sets and desquamation in consolidated Tertiary sands resulting from lateral offloading, to the relative high erodibility of glauconiferous sands, and to the sensitivity of loess and loamy soils for solifluction, rainwash and colluviation. A stability index E has been proposed for loamy soils based upon the characteristics of the liquid limit curve. Two‐year observations and measurements at the dune station of Kalmthout have shown how the loess fraction can be transported in a basal drift near the ground, and how rainstorms provoke deflation and rainwash on dunes where gravel is moving in saltation during heavy storms. Litter flow has been found to occur on all actual forested slopes. All these data on morphogenetic processes have led to some considerations of the Quaternary morphological evolution of Lower and Middle Belgium: the modelling mainly by sheetwash of periglacial glacis, the evolution of the Hageland hills and of the Plateau of Brabant, the morphodynamics of loamy slopes, Late Glacial and Holocene dune building, and finally the Holocene evolution of forested slopes.
A quantitative rill erosion study on a loamy sand in the hilly region of flanders
Authors: Gabriels D. , Pauwels J. M. , De Boodt M.
Published: February 2007

Rill and gully erosion was measured for a loamy sand ploughed field. Eight gullies in a 1.4 ha field showed a total loss of 18‐4 T, or 1‐3 mm of denudation for November and December 1974, when 213 mm of rain fell. Soil analysis showed selective removal of fine material, with particles < 50 μ held in suspension until the water infiltrated downslope. During a summer period, 353 mm of rain led to 0.7 mm denudation as sheet erosion from small plots.
Field studies of rainsplash erosion
Authors: Morgan R. P. C.
Published: February 2007

Studies on sandy soils of the Cottenham Series in mid‐Bedfordshire confirm in the field the relationships between splash erosion, rainfall energy and ground slope obtained in the laboratory experiments of other workers. Only 0·06 per cent of the rainfall energy contributes to splash erosion and rates are low, attaining a maximum of 0·082 kg m−2 y−1 on a slope of 11°. The major role of splash action is in the detachment of soil particles prior to their removal by overland flow.
The effects of the 1976 drought and autumn rainfall on stream solute levels
Authors: Foster I. D. L. , Walling D. E.
Published: February 2007

Operation of a previously existing sampling network during the 1976 drought has provided an opportunity to assess the effects of the drought and subsequent autumn rainfall on the water quality characteristics of a small catchment (9·3 km3) in East Devon. The availability of records for past years has enabled these data to be compared with longer‐term response characteristics.

Analysis indicates that the 1976 drought produced a unique solute response, with levels rising markedly during the autumn flush which resulted from the heavy rainfall following the drought period. Concentrations of several ions increased 3–4 times and NO3‐N levels exhibited even greater increases of up to 50‐fold. Some of the factors responsible for these increases and some implications are considered.
Comments on log‐quadratic relations in hydraulic geometry
Authors: Knighton A. D.
Published: February 2007

A mathematical analysis of log‐quadratic hydraulic geometry relations explains the association between the shapes of the depth and velocity curves, and identifies other properties of the relations. By considering the nature of resistance variation, a mathematical and physical argument is put forward to account for the particular shapes apparently adopted by these curves.
Ground movement at runswick bay, North Yorkshire
Authors: Rozier I. T. , Reeves M. J.
Published: February 2007

Recent ground movements, varying in importance from superficial slips to large sliding masses, are reported for slopes at Runswick Bay, North Yorkshire. The role of water in controlling both the timing and rate of such movements is stressed. An unexpected consequence of an attempt to limit coastal erosion is reported. Failures are expected to continue.
The determination of erosion rates from exposed tree roots in the piceance basin, colorado
Authors: Carrara Paul E. , Carroll Thomas R.
Published: February 2007

Tree roots, exposed by hillslope erosion in the Piceance basin of Colorado, were inspected to determine average net erosion rates during the last four centuries. Twenty pinyon pine and juniper root sections were obtained from each of five sites in this region. The date when a root was first exposed by erosion was determined, for 83 of the sections collected, by one of three methods: 1. time of initial cambium dieback; 2. interpretation of annual ring growth pattern; and 3. the earliest occurrence of reaction wood.

Analysis indicated no significant difference in erosion rates between the five study sites. However, a strong difference in erosion rates was noted between north‐facing (0–56 mm/yr) and south‐facing (1.18 mm/yr) slopes. No significant difference in erosion rates were found between various south‐facing aspects and local steepness of slopes. Significant differences were noted between erosion rate and the length of time the root was exposed to erosion. Rates of erosion on south‐facing slopes in the pinyon‐juniper community during the last four centuries are as follows: period (years ago) 0‐99 100‐199 200‐299 300‐399 erosion rate (mm/yr) 1‐79 0‐49 0‐33 0‐22.

Although there appears to be a slow increase in erosion rates during the three earliest centuries the dramatic increase during the last century may have been substantially augmented by the introduction of cattle into this region approximately one hundred years ago.
Effects of large organic material on channel form and fluvial processes
Authors: Keller Edward A. , Swanson Frederick J.
Published: February 2007

Stream channel development in forested areas is profoundly influenced by large organic debris (logs, limbs and rootwads greater than 10 cm in diameter) in the channels.

In low gradient meandering streams large organic debris enters the channel through bank erosion, mass wasting, blowdown, and collapse of trees due to ice loading. In small streams large organic debris may locally influence channel morphology and sediment transport processes because the stream may not have the competency to redistribute the debris. In larger streams flowing water may move large organic debris, concentrating it into distinct accumulations (debris jams). Organic debris may greatly affect channel form and process by: increasing or decreasing stability of stream banks; influencing development of midchannel bars and short braided reaches; and facilitating, with other favourable circumstances, development of meander cutoffs.

In steep gradient mountain streams organic debris may enter the channel by all the processes mentioned for low gradient streams. In addition, considerable debris may also enter the channel by way of debris avalanches or debris torrents. In small to intermediate size mountain streams with steep valley walls and little or no floodplain or flat valley floor, the effects of large organic debris on the fluvial processes and channel form may be very significant. Debris jams may locally accelerate or retard channel bed and bank erosion and/or deposition; create sites for significant sediment storage; and produce a stepped channel profile, herein referred to as ‘organic stepping’, which provides for variable channel morphology and flow conditions.

The effect of live or dead trees anchored by rootwads into the stream bank may not only greatly retard bank erosion but also influence channel width and the development of small scour holes along the channel beneath tree roots. Once trees fall into the stream, their influence on the channel form and process may be quite different than when they were defending the banks, and, depending on the size of the debris, size of the stream, and many other factors, their effects range from insignificant to very important.
Semi‐determinate hydraulic geometry of river channels, South Island, New Zealand
Authors: Mosley M. Paul
Published: February 2007

Data to describe the morphologic, hydrologic and sedimentologic characteristics of 72 South Island, New Zealand, rivers were collected and analysed. Nearly 70 per cent of variation in channel morphology is accounted for by differences in cross‐sectional area, slope, and cross‐section shape; only 53 per cent of the morphologic variability could be statistically ‘explained’ by the hydrologic and sediment variables used. The level of explanation varied for different morphologic variables; nearly 90 per cent of the variability in cross‐sectional area could be explained, but aspect ratio (maximum depth divided by hydraulic radius) was completely independent. Apart from the inadequacy of the measured variables as indices of the true underlying controlling factors, and the imperfect measurement and sampling procedures, the low level of explanation is probably due to the influence of factors such as floodplain vegetation, high quasi‐random variability in bark sediment character, boundary effects imposed by bedrock bluffs, and the precise sequence of flood events, none of which are easily quantified. In addition, observations indicate that there is a large random variation in channel form which cannot be related to any factor.

An attempt to relate channel morphology to flow variability, using simple indices of the latter, was unsuccessful.
Rock hardness and landform development in the Gunong Mulu National Park, Sarawak, E. Malaysia
Authors: Day Michael J.
Published: February 2007

Rock hardness, measured by the Schmidt Test Hammer, is an important factor in explaining some of the sharp contrasts in relief and wide variety of landforms in The Gunong Mulu National Park. It is also useful in consideration of contemporary geomorphological processes, such as landsliding.
Ice‐collapse induced waves and graded gravel ridges on a Lake Beach
Authors: Duck R. W. , McManus J.
Published: February 2007

Ice collapsing into the waters of proglacial Briksdal Lake, western Norway, generates waves which rework shoreline sediments. Swash establishes graded gravel ridges sub‐perpendicular to the shoreline, derived from material eroded by backwash. A terminal gravel bar at the lakeward limit of wave‐induced transport marks the maximum depth of water surface waves.
Slumping and planar sliding on hill‐slopes in Rwanda
Authors: Moeyersons Jan
Published: February 2007

Fied observations on Rwaza Hill near Butare (Rwanda) revealed the nearly omnipresence of small natural terracettes, developing as a result of superficial slips and accelerated creep movements. On the steepest slope under study, the humic A‐horizon of the soil profile migrated downslope over a mean distance of 14.5 cm from October 1977 till October 1978.

A high hydraulic conductivity horizon, displaying low cohesion and consistency characteristics as compared with overlying and underlying material, is developed at the base of the sliding soil.

Planar slides, as well as rotational slips occur, the location of failures being determined by the presence of this plane of weakness.

Generation of basal interflow in an artificial soil column showed that the state of failure is preceded by localized rheological creep of a plastic viscous soil material, undergoing seepage pressure.
Dating of post‐glacial landforms in the central howgills
Authors: Harvey A. M. , Oldfield F. , Baron A. F. , Pearson G. W.
Published: February 2007

Little is known of Holocene landform development in Upland Britain. This paper describes a site at Middle Langdale in the Howgill Fells of Cumbria where large, but now stabilized and inactive gullies cut through periglacial material. At the base of the gullies large debris cones have buried earlier alluvial sediments on the valley floor. On these sediments and buried by the debris cones is a well‐developed organic soil from which two 14C dates have been obtained in an attempt to estimate the age range of the soil. These dates range from 2580±55 years BP for the fine particulate fraction from the base of the organic horizon to 940±95 years BP for fossil rootlets from the uppermost organic layer, immediately below the overlying debris cones. The pollen evidence suggests that the valley floor site was initially dominated by alder carr and later by a Juncus marsh with birch, alder and hazel nearby. The pollen, from the surrounding upland area suggests woodland on the valley sides, dominated by oak and elm that was later replaced by a more open environment rich in heath species and in which disturbed ground species were present. The magnetic evidence indicates a stable local environment during soil formation but shows a sudden inwash of unweathered debris at the top of the buried soil.

The evidence suggests that the valley floor was geomorphologically stable throughout the period of soil formation, although there was a local change in valley floor vegetation and a reduction of woodland cover on the valley sides at sometime during the period. The evidence then points to major geomorphological changes; a wave of soil erosion, gully development and debris cone deposition, perhaps following the Scandinavian introduction of sheep farming in the tenth century A.D.
Hydrologic and geologic control of carbonate water chemistry in the subarctic nahanni karst, canada
Authors: Brook George A. , Ford Derek C.
Published: February 2007

There are six classes of water and five geologic environments in the subarctic Nahanni karst. During the summers of 1972 and 1973, 214 water samples were collected from 15 of the 30 hydrogeologic categories. Linear discriminant function analysis, using five measured and two derived chemical variables, indicates that there are statistically significant (0.005 level) differences in water chemistry between similar waters in different geologic environments, between waters in the same geologic environment, and between waters in different hydrogeological categories. Geological environment labels a natural water because it determines the availability of soil CO2 and of soluble minerals. Measurements indicate that mean soil log PCO2 is greatest in areas of shale mantled by till (−2.39), and least in areas of sandy fluvioglacial drift (−3.27). Low values on the sandy drift are due to the sparse shrub vegetation, and to the high degree of soil aeration; soils in areas of shale are clay‐rich and support a dense boreal forest. Hydrology influences water chemistry because it determines how much CO2 natural waters pick up from the environment and how much they subsequently lose to the atmosphere, and as a result, whether they dissolve or deposit soluble materials. The similarity between mean calculated log PCO2 in natural waters (−2.92) and mean measured soil log PCO2 (−2.80) suggests that natural waters in Nahanni are dose to equilibrium with mean soil CO2 levels.
The effect of forestry drainage operations on upland sediment yields: A case study
Authors: Robinson M. , Blyth K.
Published: February 2007

Forestry is generally considered to be a land use giving low sediment yields. However, in Britain most forestry is on land that requires extensive drainage, and it was found that the drainage of a small upland catchment resulted in sediment yields over the following five years equivalent to nearly half a century's load at pre‐drainage rates. Subsequent sediment yields did not decline to pre‐drainage levels, but remained about four times higher, as a result of erosion of the drains.
Toppling failures from alpine cliffs on ben Lomond, Tasmania
Authors: Caine Nel
Published: February 2007

Large cliff failures involving forward toppling over a basal hinge have occurred on more than half of the plateau edge of Ben Lomond, northeastern Tasmania. This mode of failure, which is readily identified from the columnar structure of the dolerite involved, has affected up to 107 m3 of rock at a time and a total of more than 50 × 106 m3 in all the cases which can still be identified. It represents perhaps the most important form of cliff retreat, amounting to a rate of 0.2 mm yr−1 over the last 100,000 years.

Topographic evidence and joint surveys suggest that two different mechanisms have produced the topples on Ben Lomond. One has involved failure in the sediments underlying the dolerite with consequent foundering and cambering of large sections of the plateau edge. This mechanism accounts for relatively few of the Ben Lomond topples, though it includes the largest individual cases. The second mechanism, dominant in most of the topples, involved slab failure in the cliffs. Both modes of failure have been facilitated by vertical weaknesses within the bedrock and both require an initially steep cliff profile. Because of the latter requirement, which is not met on the other mountains of northeastern Tasmania, large‐scale topples are found only on Ben Lomond, and only there where glacial steepening of the cliff has been possible. Following the initial failure, topples of both types have migrated downslope by block sliding for distances up to 2 km.
Short term fluctuations in dissolved organic matter concentrations in streamflow draining a forested watershed and their relation to the catchment budget
Authors: Foster I. D. L. , Grieve I. C.
Published: February 2007

Dissolved organic matter (DOM) concentrations in throughfall, throughflow, and runoff were recorded in a small (95 ha) woodland catchment in North Warwickshire for a period of eight weeks following a prolonged dry spell. DOM is shown to be positively related to stream discharge over the sampling period, although distinctive flushing effects were identified. The net contribution of DOM to total dissolved solids load carried in the river was only 2.4 per cent, and represented significantly less than published carbon losses by mineralization of soil organic matter. Throughfall inputs were some 100 times higher than streamflow outputs from the catchment.
Field measurements of rainfall drop‐size distribution, and the relationships between rainfall parameters and soil movement by rainsplash
Authors: Kneale W. R.
Published: February 2007

Rainfall drop‐size distributions were measured at a site in northern England using the ‘oflour‐pellet’ technique. A relationship between intensity and kinetic energy is presented. Even at the low rainfall intensities observed (< 5 mm h−1 average over an hour) measureable amounts of rainsplash movement took place, and these movements have been related to rainfall parameters.
Evaporite dissolution and development of karst features on the rolling plains of the texas panhandle
Authors: Gustavson Thomas C. , Smpkins William W. , Alhades Alan , Hoadley Ann
Published: February 2007

More than 400 dolines, consisting of collapse sinkholes and closed depressions, occur in Hall and Briscoe Counties, Texas. Of these, at least 36 sinkholes and two depressions formed between 1940 and 1972. Collapse sinks are typically circular and range up to 100 m in diameter and 15 m in depth. Closed depressions are irregularly‐shaped, internally‐drained depressions up to 2.4 km in length. Surface fractures up to 1.5 km in length are associated with certain closed depressions.

Karst features are forming as a result of intrastratal dissolution of Upper Permian evaporites, primarily halite and secondarily gypsum. Salt dissolution and overburden collapse are evident from geophysical log cross‐sections and occur at depths ranging from 195 to 275 m. Dissolution is progressing down dip and mean dissolution rates for salt beds in the Hall County area range from 0.29 to 7.73 cm/yr.

The valley of the Prairie Dog Town Fork of the Red River is an area of ground‐water discharge for flow systems moving eastward from topographically high areas of the Rolling Plains and from the eastern rim of the High Plains. Halite beds in contact with these waters undergo dissolution. Salt springs and brine seeps, some associated with sinkholes and depressions, occur in the discharge area and indicate that dissolution is an ongoing process.
Test of scale modelling of sediment transport in steady unidirectional flow
Authors: Southard John B. , Boguchwal Lawrence A. , Romea Richard D.
Published: February 2007

In two steady uniform flows at different physical scales in a small open channel, with variables characterizing flow, sediment, and fluid adjusted for dynamic similitude by means of four dimensionless modelling parameters (a Reynolds number, a Froude number, a density ratio, and a length ratio), measured frequency distributions of height, spacing, and migration rate of current ripples were almost identical when scaled, thus verifying that exact Reynolds‐Froude modelling of loose‐sediment transport is valid and workable. Modelling should be valid as well for a wide range of other transport conditions in the same kind of flow, because no additional kinds of forces or effects would be present in transport of loose grains in modes other than as ripples. In scaled‐down modelling, a scale ratio of 2.5 is attainable without recourse to exotic fluids by use of water at 85°C to model natural flows at 10°C.
A simulation study of the development of rillenkarren
Authors: Glew J. R. , Ford D. C.
Published: February 2007

Rillenkarren are patterns of tightly packed, small solution rills found upon bare, sloping surfaces of soluble rocks in all climates. They head at the crest of a slope and are replaced downslope by a planar solution surface, the ausgleichfläche. Development has been simulated successfully using a rainfall simulator and plaster of paris blocks. Ten principal experiments were completed with blocks at inclinations ranging 22½–60°, temperature and rainfall intensity being constant. Results suggest that rillenkarren develop within a hydrodynamic zone of rim effect where the depth of threads or sheets of runoff is insufficient to prevent direct raindrop impact upon the underlying soluble solid. Where depth of runoff becomes sufficient rills are replaced by the ausgleichfläche. Between upper and lower limits, rill length is proportional to slope in a log linear manner. Rill cross‐sections approximate the parabola, the most effective shape for focussing raindrop erosion in the axis of the trough: this explains the tight packing characteristic. Ausgleichfläche and rill troughs evolve by parallel retreat at the original slope angle, the erosion rate being greatest at about 45°.
Longshore variations in nearshore wave processes at magilligan point, northern ireland
Authors: Carter R. W. G.
Published: February 2007

Magilligan Point is a recurved cuspate foreland at the mouth of Lough Foyle. Two wave regimes intersect in the estuary mouth and the manner of their interplay controls shoreline changes. Ocean swell waves from the N and NE are refracted around the recurve, losing both height and energy longshore. Width of the surf zone decreases and waves tend to steepen, although both these changes and wave refraction owe something to nearshore geometry. Angle of wave approach becomes more acute and a westerly flowing longshore current moves sand S and SW along the beach. Estuary waves from the S and SW are wind‐driven with high‐frequencies and steepnesses. They generate a northeasterly current which returns material N, but dies out as the waves become obliterated by nearshore attenuation and breaking of swell. It is possible to identify a time‐averaged null‐point where shoreline wave power is balanced, although this tends to shift over short periods causing rapid morphological changes. The existence of two independent, but counteractive cells ensures the long‐term maintenance of the foreland, without requiring major or continuous supplies of fresh sediment.
Magnitude frequency study of rockfall in Co. Antrim, N. Ireland
Authors: Douglas G. R.
Published: February 2007

Detailed observations of rockfall were kept on a weekly basis over a two year period. The results indicate that there is both a seasonal distribution of rockfall with maxima in February‐March and November–December, and continuous small scale rockfall throughout the year.

There appears to be some connection between rockfall and frost processes, while the peculiar geotechnical properties of the lava flows in county Antrim, in particular the presence of microfractures, would seem to be the main underlying cause for the observed activity.
A study of the infiltration characteristics of undisturbed soil under simulated rainfall
Authors: Johnston Harold T. , Elsawy Elsayed M. , Cochrane Stanley R.
Published: February 2007

Infiltration is the single most important parameter in deriving the net quick response rainfall which contributes to stream flood discharges.

Rainfall simulation is used to study the infiltration characteristics in a typical catchment, the Six Mile Water in N. Ireland. The design of the simulator was such that it could be easily moved from one test area to another within the catchment to examine the effect of soil and slope variation. The simulator was first calibrated in controlled laboratory conditions and later the calibration was checked in the field.

The simulator was mounted over an undisturbed plot of 37 m2 and the surface runoff from the area measured by means of a collecting channel located along a lower edge of the plot. Soil moisture variations were monitored using a soil moisture neutron probe. Soil classification tests and gravimetric moisture contents were carried out on each plot.

The field tests were carried out with variations in rainfall intensity, initial conditions, changing seasons, and for different plots within the catchment area. The results obtained are unique in that they present data obtained under field conditions for undisturbed soil within a natural catchment. The infiltration behaviour was found to depend upon rainfall intensity, initial conditions of the plot under consideration, seasonal temperature, and a slope of the plot. The data showed that while a classical Horton type equation for infiltration was suitable for the later stages of each test result when significant surface runoff was taking place, the model failed to represent early response adequately due to storage effects being omitted in the equation. A modified form of Horton equation is proposed, which models more accurately the infiltration characteristics of the full period of each test run.
Definition of a minimal region of deletion of chromosome 7 in uterine leiomyomas by tiling‐path microarray CGH and mutation analysis of known genes in this region
Authors: Vanharanta Sakari , Wortham Noel C. , Langford Cordelia , El‐Bahrawy Mona , van der Spuy Zephne , Sjöberg Jari , Lehtonen Rainer , Karhu Auli , Tomlinson Ian P.M. , Aaltonen Lauri A.
Published: February 2007

Somatic interstitial deletions of chromosome segment 7q22–q31 in uterine leiomyomas are a frequent event, thought to be indicative of a tumor suppressor gene in the region. Previous LOH and CGH studies have refined this region to 7q22.3–q31, although the target gene has not been identified. Here, we have used tiling‐path resolution microarray CGH to further refine the region and to identify homozygous deletions in fibroids. Furthermore, we have screened all manually annotated genes in the region for mutations. We have refined the minimum deleted region at 7q22.3–q31 to 2.79 Mbp and identified a second region of deletion at 7q34. However, we identified no pathogenic coding variation. © 2007 Wiley‐Liss, Inc.
The Love Life of the Zebra Finch
Authors: Unterstell Rembert
Published: February 2007

Behavioural geneticist Wolfgang Forstmeier investigates the fundamental basis and consequences of sexual behaviour
The Fight for Survival in the Mountain Forest
Authors: Klaus Siegfried , Sun Yue‐Hua , Scherzinger Wolfgang
Published: February 2007

The Lianhuashan Nature Reserve in China is home to many plant and animal species. But, as the example of the Chinese grouse shows, this habitat is under threat. Only the determined protection of the mountain forests of Central Asia can ensure the future of this unique biocoenosis
A Late Palaeozoic‐Early Mesozoic marginal basin along the actives sourthern continental margin of Eurasia: Evidence from the central Pontides (Turkey) and adjacent regions
Authors: Ustaömer Timur , Robertson Alastair H. F.
Published: February 2007

Remnants of two ‘Palaeotethyan’ oceanic basins are exposed in the Central Pontides of northern Turkey, separated by a continental sliver and an oceanic arc. The southern basin corresponds to the main Tethys (‘Palaeotethys’), which partially closed in Early Mesozoic time following northward subduction under the southern, active continental margin of Eurasia.

The northern basin (Küre Complex) opened above the ‘Palaeotethyan’ subduction zone as a marginal basin, following rifting of a continental fragment (Istanbul fragment) from Eurasia. Marginal basin opening apparently dates from the Late Palaeozoic in the east (Küre basin) and from the Triassic in the west (Kocaeli basin). Basin closure was achieved by southward subduction‐accretion, in pre‐Late Jurassic times, leaving ‘Neotethys’ open to the south.

Counterparts of the Küre Complex are found in the adjacent Crimea (Taurian Series), Istranca (Zabernevo Complex), Dobrogea (Nalbant flysch) and Caucasus (pre‐Late Jurassic Southern Slope Basin) regions. Basin opening was accompanied by oceanic crust genesis, at least in the Pontides and Caucasus. Closure before Mid‐Jurassic time was achieved by subduction‐accretion processes, whereby oceanic crust and deep‐sea sediments (including sulphides) were detached and structurally assembled, while oceanic basement was subducted. Marginal basin opening and closure is seen as one in a series of events along a long‐lived, active south Eurasian continental margin.
Geological history of the northward arched segment of the North Anatolian Transform Fault Zone
Authors: Dirik Kadir
Published: February 2007

The study area is located in the southern part of the Central Pontides. The rocks exposed in this region have been divided into three major groups: basement, cover sequence and volcanic rocks. The basement rocks are composed of metamorphic units and a chaotic assemblage derived from an accretionary prism produced during the northward subduction of northern Neo‐Tethys during the Late Cretaceous. During the same period, the basal element of the cover sequence, a thick and coarsening upward flysch succession (Cankurtaran Formation) was deposited in a tectonically active forearc regime. Towards the end of the Early Palaeocene, the entire study area emerged and became the site of erosion. During the Late Palaeocene to Early Eocene, the northern and southern parts of the study area were invaded by a new transgressing sea. This period was followed by uplift, volcanic activity and the formation of regressive sequences, events resulting from continental collision between the Anatolian and Pontide blocks during Late Eocene to Early Miocene times.

Continuing convergence between the Anatolian and Pontide blocks resulted in conversion of the compressional‐contractional regime into a compressional‐extensional regime and the inception of the North Anatolian strike‐slip system during the Late Miocene‐Early Pliocene period.
Geochemical characteristics of granitoids along the western margin of the Central Anatolian Crystalline Complex and their tectonic implications
Authors: Akiman Orhan , Erler Ayhan , Göncüoǧlu M. Cemal , Güleç Nilgün , Geven Akin , Türeli̇ T. Kemal , Kadioǧlu Yusuf K.
Published: February 2007

The closely related assemblage of igneous and metamorphic rocks that lie within a triangular area approximately bounded by the Tuzgölü Fault, the Ecemiş Fault and the Izmir‐Ankara‐Erzincan Suture and between the lines connecting Ankara, Sivas and Niǧde is called the Central Anatolian Crystalline Complex (CACC). The granitoids cropping out within the CACC can be divided areally into three groups: (1) a large number of individual small plutons which form an arcuate set and curve from NE‐SW to NW‐SE and extend from Sulakyurt to Niǧde along the western margin; (2) a relatively narrow and smaller set of disconnected plutons extending from Sivas to Çamardi along the eastern margin; and (3) a very large batholith along the northern margin exposed around Yozgat.

This study deals only with the first group of rocks. Geochemical data have been used to classify the granitoids, to determine their chemical characteristics, and to estimate the possible source regions and tectonic environment of magma generation and emplacement. The geochemical data indicate that these western margin granitoids range in composition from monzonitic to granitic‐granodioritic varieties, belong to the alumina‐cafemic and cafemic associations and possess either a metaluminous or peraluminous character. All granitoid types display features which may indicate the presence of both S‐ and I‐type igneous rocks. Interpretation of the trace element data suggests a syncollisional to late/post‐collisional tectonic setting and a continental crustal source for the granitoids.
Ophiolites and related metamorphic rocks from the Kütahya region, north‐west Turkey
Authors: Önen A. P. , Hall R.
Published: February 2007

The Izmir‐Ankara‐Erzincan suture zone is the major Neotethyan suture in northern Anatolia. Two areas of ophiolitic rocks from this zone have been studied. The Beşdeǧirmen area, north of Kütahya, includes dismembered ophiolitic rocks (the Kinik Ophiolite) and consists of serpentinized pyroxenites and periodotites together with gabbros and gabbro dykes. The Kaynarca area, south‐east of Kütahya, contains medium to low grade metamorphic rocks (mainly amphibolites, amphibole schists and quartz schists) at the base of the Kinik Ophiolite. These two areas are probably joined under the Neogene cover.

The Beşdeǧirmen pyroxenites contain spinel with a Cr number [Cr/(Cr + Al)] < 0·60 and are similar to peridotites from mid‐ocean ridge (MOR) settings. Gabbro samples contain very calcic plagioclase (An87–100) and magnesio‐hornblende as the principal phases; prehnite and zeolite are the most common late stage fracture infillings. The chemistry and mineralogy of the gabbros have features similar to rocks from both MOR and arc settings.

For the Kaynarca amphibolites there are at least two stages of amphibole growth. The first stage amphiboles are brownish green calcic varieties. In contrast, the second stage amphiboles record a medium to high pressure overprint with the growth of fibrous, bluish green varieties. The low crossite content of the amphiboles, and the absence of lawsonite, suggest the transition between blueschist and greenschist facies metamorphism. Trace element and rare earth element data from the amphibolite samples are comparable with oceanic island basalts.

Isotopic dating suggests a Coniacian‐Ypresian age for the formation of the Beşdeǧirmen gabbros, significantly younger than the Jurassic ages previously suggested for the formation of the main Izmir‐Ankara ocean. Unlike many other Tethyan ophiolites the Kinik Ophiolite appears to represent a fragment of a Neotethyan ocean, rather than a supra‐subduction zone environment. We suggest a back‐arc basin setting for the formation of the Beşdeǧirmen ophiolitic rocks.

The Kaynarca rocks formed as an oceanic island or seamount and the Kaynarca amphibolites were formed by intra‐oceanic thrusting during the closure of the Izmir‐Ankara‐Erzincan ocean. Preliminary isotopic data suggest an Albian‐Campanian age for this sub‐ophiolite metamorphism. The sub‐ophiolite metamorphic rocks were overprinted by low temperature‐high pressure metamorphism related to Late Cretaceous subduction. Final emplacement is related to the terminal collisional event which occurred at the end of the Cretaceous.