bluuebunny/crossref_metadata_2025 huggingface dataset:
Variations Dilatométriques de Cylindres de Roches Calcaires Subissant des Cycles de Gel‐Dégel
Authors: Prick A. , Pissart A. , Ozouf J.‐C.
Published: February 2007

Les variations de diamétre et de longueur de cylindres de roches calcaires poreuses ont été mesurées au cours de cycles de gel‐dégel. Il est apparu ainsi l'existence de variations de dimension de ces roches, fort complexes et non isotropiques. Ces variations résultent essentiellement de la migration d'eau non gelée au sein des échantillons; ces migrations, dirigées vers les pores le plus larges ou vers les faces des échantillons exposées d'abord au front de gel, produisent des contractions là où des dilatations auraient été attendues. Les expériences soulignent toute l'importance du degré d'humidité des échantillons, de la porosité de la roche, de la vitesse de gel et de faibles variations éventuelles des dispositifs expérimentaux utilisés. Ces mesures dilatométriques donnent pour les variations de longueur des échantillons, des indications précieuses sur les tensions que subissent les roches sous l'action du gel et paraissent ětre une méthode d'étude prometteuse de la gélivation.
Changes in the extent of permafrost during the late quaternary period in the territory of the former Soviet Union
Authors: Kondratjeva Kalerija A. , Khrutzky Stanislav F. , Romanovsky Nikolai N.
Published: February 2007

The cryolithozone occupies a considerable part of the territory of the former Soviet Union. During the Zyriansk (50,000–60,000 years BP) and Sartansk (15,000–27,000 years BP) cold periods of the late Pleistocene, permafrost developed to its maximum thickness and spread as far south as 48–49°N on the Russian plain. In western Siberia and the European north‐east, relict Pleistocene permafrost is separated at depth from late Pleistocene permafrost by a thaw layer; in middle and eastern Siberia where no ice sheets developed, the permafrost is continuous and thick. During the late Glacial to early Holocene warming, the extent of the cryolithozone diminished and thermokarst processes intensified. Using geothermal data from deep boreholes, the approximate rock palaeotemperatures for the last 12,000 years are described for the Russian plain, western Siberia and eastern Siberia.
Talus movement in the high equatorial andes: A synthesis of ten years of data
Authors: Pérez Francisco L.
Published: February 2007

The surficial movement of debris was monitored on a talus cone in the Venezuelan Andes for about a decade. The talus surface was classified into three textures (blocks, pebbles, sand). Painted stones were placed along four transects perpendicular to the slope; many markers (≈︁ 36%) were lost, mostly in pebble and sand areas, owing to burial. Mean stone movement decreased downslope, being much lower on the talus base (33.8 cm) than on the lines above (157.9, 239.9 and 107.8 cm). Tracers on blocks shifted a shorter distance (36.9 cm) than those on either pebbles (152.3 cm) or sand (225.1 cm). A regression showed that annual movement rates on 46 plots were inversely correlated with mean particle size (r=−0.878). An ANOVA indicated that the difference in rates between textures was more significant than that found between slope positions. Markers below outcrops also moved less than those on open talus. A line painted on the rockwall at the talus apex showed alternate periods of debris erosion and accretion, with an overall drop of 22.2 mm of the talus surface during a period of 11.5 years. Rates of debris movement vary substantially between talus textures because these are affected by different transport processes. Mean rates of debris movement remained essentially erratic during the study period, showing no consistent trends through time.
Present and past geocryogenic processes in Mexico
Authors: Heine Klaus
Published: February 2007

Periglacial processes and landforms are described from the Cordillera Neovolcánica of central Mexico. Inactive rock glaciers are related to different late‐glacial and Holocene phases of permafrost conditions. Active discontinuous permafrost occurs above c. 4600 m ASL and appears to be from the Little Ice Age. The lower limit of late‐glacial rock glaciers is situated 500 and 600 m lower than during the Little Ice Age.
Quantitative estimation of cryogenic weathering energy
Authors: Vasiliyev A. A.
Published: February 2007

Experiments to measure the energy released by the cryogenic weathering of sandstone and shale are described. The energy released by fracturing is thought to be proportional to the importance of new surfaces appearing in the rock at the time of disintegration. The specific surfaces of samples which have been submitted to freezing have been determined by an absorption technique. The energy released by disintegration of sandstone is about −400 Kj/m2 of specific surface, and for shale is 700 Kj/m2. These values represent less than 1–2% of the heat flux of the frozen rock and have a negligible effect therefore, on the thermal region of the active layer.
Some observations regarding sorted stripes, livingston island, south shetlands
Authors: Hall Kevin
Published: February 2007

Sorted stripes have long been recognized in the sub‐Antarctic and the maritime Antarctic. The cold and wet conditions of these regions, when compared with the drier continent, are ideal for their development. In particular, the frequent low‐amplitude, short‐duration freeze‐thaw cycles of the sub‐Antarctic favour the development of miniature sorted forms. The maritime Antarctic, however, with its larger amplitude and longer duration of freeze‐thaw cycles, plus the presence of permafrost, exhibits a more frequent occurrence of the larger forms.

The Byers Peninsula has an extensive range of sorted features but, despite being situated in the maritime Antarctic and within a permafrost zone, the majority of these features are of the miniature variety. In addition, the sorted stripes exhibit a distinct spatial preference. Their alignment and spatial distribution are not associated with either the sun or the wind, but are a function of the snow cover.
Water migration and ice segregation in the transition zone between thawed and frozen soil
Authors: Solomatin V. I. , Xu Xiaozu
Published: February 2007

Samples of silty clay were kept under constant boundary temperature conditions of +1°C (top) and −1°C (bottom) in a series of cold room laboratory experiments. Water migration and ice enrichment near the permafrost table were observed in all samples. Cryogenic layering was observed in soil layers with boundary temperature conditions of −0.5 to −1.0°C. These results confirm earlier observations which explain the occurrence of an ice‐rich layer near the permafrost table, and they may be used to explain the influence of snow cover on isotopic composition of near‐surface ground water and ice.
Ground temperature and related permafrost characteristics in west greenland
Authors: Van Tatenhove Frank G. M. , Olesen Ole B.
Published: February 2007

Shallow and surficial ground temperatures in west Greenland are presented and reviewed together with available deep temperature profiles in the unglaciated area of west and southwest Greenland. Ground temperature measurements in Kangerlussuaq (Søndre Strømfjord) reveal a temperature at the depth of zero annual amplitude, TZAA, of −1.6 ± 0.2°C. The average thickness of the active layer is 1.7 m and the permafrost thickness is estimated to be 127 ± 31 m. The permafrost thickness in Sisimiut (Holsteinborg) is estimated to be 33 ± 9m with TZAA at −0.3 ± 0.1°C. In Sisimiut, the average active layer thickness is 2.3 m. Between Kangerlussuaq and the ice sheet margin, permafrost is continuous and the active layer thickness is between 0.15 and 5.0m. The interactions between geomorphology, wind pattern, snowcover characteristics and paths of snow meltwater play an important role in determining the variability in ground temperature and permafrost thickness over short distances. The distribution and redistribution of available water are especially important in the low‐precipitation area near the ice margin in central west Greenland. Therefore soil temperatures tend to be colder in low‐lying, organic‐rich soils with dense vegetation than in sandy, inorganic soils with discontinuous vegetation. Within a west Greenland perspective, ground temperature in Sisimiut is relatively warm and in Kangerlussuaq relatively cold owing to their respectively more oceanic and continental climatic regimes.
Active patterned ground and cryoturbation on Muckish mountain, Co. Donegal, Ireland
Authors: Wilson Peter , Sellier Dominique
Published: February 2007

Active stony earth circles occur on the less coarse cells of relict sorted nets developed in quartzite debris above 600m ASL on Muckish Mountain, north‐west Ireland. The earth circles are underlain by deformed and truncated podzolic soil horizons that resemble cryoturbations produced by differential frost heave of adjacent sediments. Grain‐size distributions indicate that the soils are frost‐susceptible and possess negative frost‐susceptibility gradients. This infrequent association of coarse quartzite debris and fine‐grained frost‐susceptible matrix probably arises from the weathering of thin inter‐bedded pelites (schists) within the quartzite. Recent activity may have been triggered by climatic deterioration during the Little Ice Age, although present climate on Muckish appears capable of maintaining the surface morphology of the stony earth circles. These features, along with forms described previously, suggest that most if not all upland areas in Ireland above 600‐700m ASL possess climatic conditions favouring frost‐related soil processes.
Grèzes, grèzes litées: Historique des définitions
Authors: Ozouf J.‐C. , Coutard J.‐P. , Lautridou J.‐P.
Published: February 2007

The terms grèze and grèze litée, introduced by Y. Guillien to define a special type of slope deposit, are often not well used by authors. It is necessary to recall the initial definitions. The grèze is a sandy and gravelly material produced by frost shattering: mode 2.5 mm, maximum size 25 mm. The use of the term éboulis ordonnés as a synonym for grèze litée should be avoided because this type of deposit accumulates by solifluction and runoff processes, not by successive rockfalls.
Processus Génétiques à l'origine des Formations de Pente à Graviers de Craie en Champagne
Authors: Laurain M. , Guérin H. , Marre A. , Richard Et J.
Published: February 2007

En Champagne, des dépts de pente stratifiés crayeux connus sous le nom de ‘graveluche’ sont nombreux. Ils sont formés de dèbris calcaire dont la taille varie de 2 à 3 mm jusqu'à 1 à 2 cm et d'une matrice silteuse. Des lits gras alternent avec des lits maigres. Trois explications différentes ont été proposées pour en expliquer la genèse; il s'agirait soit: 1) de depots éoliens, 2) de dépǒts de solifluxion, 3) de dépǒts résultant d'écoulements gravitaires mal précisés.
Models for the genetic and environmental interpretation of stratified slope deposits: Review
Authors: van Steijn Henk , Bertran Pascal , Francou Bernard , Texier Jean‐Pierre , Hétu Bernard
Published: February 2007

The principal aspects addressed are the relationships between transport processes and de‐positional environments, and the sedimentary properties of the deposits. The following ‘process‐product’ models are discussed: (a) stone‐banked solifluction sheets or lobes, (b) dry grain flows and frost‐coated clast flows, (c) debris flows, and (d) niveo‐aeolian transport within the context of talus development. Problems of convergence, the possible role of other processes, and the climatic significance of stratified slope deposits are briefly discussed.
Quelques Considérations Concernant des Formations de Pente dans les Carpates Méridionales
Authors: Urdea Petru
Published: February 2007

En Roumanie les formations de pente des Carpates Méridionales sont peu étudiées. Le présent article est consacré aux formations de pente des zones alpine et forestière des montagnes Fgraş, Retezat et Cǎndrel. Des analyses morphographiques, morphométriques, granulométriques et minéralogiques mettent en évidence les particularités de ces formations. Celles‐ci indiquent les processus génétiques permettant de différencier éboulis de gravité, éboulis à avalanches, bourrelets‐protalus, éboulis fluants, éboulis ruisselés, cǒnes et talus d'avalanches, éboulis soliflués et dépǒts de solifluxion. Ces formes sont présentes surtout dans les régions alpines formées de schistes cristallins et largement développées dans les montagnes de Fǎgǎraş, et Cǎndrel. L'analyse minutieuse des éboulis stratifiés, et leurs rapports spatiaux avec les terrasses quaternaires apportent de nouvelles données permettant des conclusions paléoclimatiques pour cette partie de l'espace carpatique.
Secretagogin is a new neuroendocrine marker in the human prostate
Authors: Adolf Katja , Wagner Ludwig , Bergh Anders , Stattin Pär , Ottosen Peter , Borre Michael , Birkenkamp‐Demtröder Karin , Ørntoft Torben Falck , Tørring Niels
Published: February 2007

Background

Neuroendocrine (NE) differentiation in prostate cancer (PCa), promoted by NE cell secreted products, appears to be associated with tumor progression, poor prognosis, and hormone‐refractory disease. We recently reported secretagogin, a hexa‐EF‐hand Ca2+ binding protein, as a novel NE marker in carcinoid tumors of the lung and the gastrointestinal tract. The present study analyzes the expression of secretagogin in normal and malign prostate tissue.

Methods

We analyzed immunoreactivity for secretagogin, chromogranin A (CgA), neuron specific enolase (NSE), and synaptophysin (SYN) in consecutive sections from 87 formalin‐fixed paraffin‐embedded (FFPE) benign hyperplastic (n = 10) and prostate adenocarcinoma (n = 77) specimens. The intracellular distribution of secretagogin, CgA, and NSE was examined by confocal fluorescent microscopy, and we characterized secretagogin in eight samples by Western blotting.

Results

Secretagogin is cytoplasmic and nuclear expressed in NE and NE differentiated cells, and to a lesser extent in epithelial cells, in the benign prostate and prostate adenocarcinoma cells. Secretagogin stained 82% (46/56) of benign and 71% (48/68) of prostate adenocarcinomas and co‐localized with the NE markers CgA and NSE. The expression of secretagogin is significantly correlated to CgA (P < 0.001) and NSE (P < 0.048) in prostate adenocarcinoma and to CgA in normal epithelium (P < 0.028).

Conclusions

Secretagogin is a novel NE marker in the prostate with more extended immunoreactivity compared to the NE markers CgA, SYN, and NSE. Secretagogin is widely expressed in prostatic adenocarcinoma as opposed to adenocarcinomas in other organs. Prostate 67: 472–484, 2007. © 2007 Wiley‐Liss, Inc.
Understanding the folding and stability of a zinc finger‐based full sequence design protein with replica exchange molecular dynamics simulations
Authors: Li Wenfei , Zhang Jian , Wang Wei
Published: February 2007

Full sequence design protein FSD‐1 is a designed protein based on the motif of zinc finger protein. In this work, its folding mechanism and thermal stability are investigated using the replica exchange molecular dynamics model with the water molecules being treated explicitly. The results show that the folding of the FSD‐1 is initiated by the hydrophobic collapse, which is accompanied with the formation of the C‐terminal α‐helix. Then the folding proceeds with the formation of the β‐hairpin and the further package of the hydrophobic core. Compared with the β‐hairpin, the α‐helix has much higher stability. It is also found that the N‐capping motif adopted by the FSD‐1 contributes to the stability of the α‐helix dramatically. The hydrophobic contacts made by the side chain of Tyr3 in the native state are essential for the stabilization of the β‐hairpin. It is also found that the folding of the N‐terminal β‐hairpin and the C‐terminal α‐helix exhibits weak cooperativity, which is consistent with the experimental data. Meanwhile, the folding pathway is compared between the FSD‐1 and the target zinc finger peptide, and the possible role of the zinc ion on the folding pathway of zinc finger is proposed. Proteins 2007. © 2007 Wiley‐Liss, Inc.
The reflection, absorption, and transmission of solar radiation by fog and cloud
Authors: Hewson E. W.
Published: February 2007

Starting from Mecke's analysis of the absorption and scattering by water droplets, a system of equations is derived from which may be computed the fractions of the sun and sky radiation incident on a fog or cloud which will be reflected, absorbed and transmitted. These fractions are found to vary with the size of the droplets, the thickness of the fog or cloud, and the density, or amount of liquid water per cubic metre. The zenith distance of the sun also has a slight effect, but this is very small by comparison with the effects of the other variable factors.

Drops of radius 2 × 10−3 cm. are taken as typical of fog, and drops of radius 5 × 10−4 as typical of cloud. Table I gives, for fog and cloud, for three values of the density, 0.1 gm./m.3 (diffuse), 1.0 gm./m.3 (moderate) and 5 gm./m.3 (dense), and for thickness of cloud or fog of 20 m., 80 m. and 200 m., and also, for 1,000 m,. and 4,000 m. for cloud, the theoretically computed values of the fractions of incident radiation which are scattered, absorbed and transmitted.

A fog is found to reflect less, absorb more, and transmit more, than cloud of the same density and thickness (vertical extent). A diffuse fog of density 0.1 gm/m.3 transmits 98.5 per cent if its thickness is only 20 m., and 86.6 per cent if its thickness is 200 m. In order to reflect 80 per cent of the incident radiation, a cloud of density 1.0 gm./m.3 must have a thickness of at least 150 m., while a cloud of density 5.0 gm./m.3 must have a thickness of at least about 50m.

The absorption is greatest in the upper layers of the cloud or fog, and so tends to increase the lapse rte within the liquid bearing layer, but this tendency is masked by the interchange by long‐wave radiation, which cools the upper part of the cloud while warming the lower layers.

No observational data are available in a suitable form for comparison with the results displayed in Table I.
Characterization of phenolic compounds in the fruits of Forsythia suspensa by high‐performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry
Authors: Guo Hui , Liu Ai‐Hua , Ye Min , Yang Min , Guo De‐An
Published: February 2007

Phenolic compounds are the major bioactive constituents of Forsythia suspensa, an important Chinese herbal medicine used for the treatment of various infectious diseases. Fragmentation behaviors of the phenolic compounds in F. suspensa were investigated by using a high‐performance liquid chromatography/tandem mass spectrometry (HPLC/MSn) method. For common phenylethanoid glycosides, the loss of the caffeoyl moiety was the first fragmentation step, then sequential losses of rhamnose, hexose and water were observed in further fragmentations. If a substituent group presented in the β position, the fragmentation was triggered by initial loss of a substituent group to form structures such as suspensaside A. Then it underwent the common fragmentation pathways as mentioned above, or eliminated characteristic residues of masses 134 or 152 Da, respectively. The latter pathway is reported here for the first time. The fragmentation behaviors of furofuran lignans displayed a typical cleavage of the tetrahydrofuran ring. However, the presence of a hydroxyl group at C‐1 led to the successive loss of 30 Da. Neutral loss of CO2 and benzyl cleavage were characteristic for lignans with a 2,3‐dibenzylbutyrolactone skeleton. A neutral loss of 30 Da was also observed in the fragmentation pattern of flavonols. These fragmentation rules were implemented to analyze phenolic compounds in the fruits of F. suspensa. A total of 51 compounds, including 24 phenylethanoid glycosides, 21 lignans and 6 flavonols, were identified or tentatively characterized based on their retention times, UV spectra and MS fragmentation patterns. Copyright © 2007 John Wiley & Sons, Ltd.
Adduct simplification in the analysis of cyanobacterial toxins by matrix‐assisted laser desorption/ionization mass spectrometry
Authors: Howard Karen L. , Boyer Gregory L.
Published: February 2007

A novel method for simplifying adduct patterns to improve the detection and identification of peptide toxins using matrix‐assisted laser desorption/ionization (MALDI) time‐of‐flight (TOF) mass spectrometry is presented. Addition of 200 µM zinc sulfate heptahydrate (ZnSO4 · 7H2O) to samples prior to spotting on the target enhances detection of the protonated molecule while suppressing competing adducts. This produces a highly simplified spectrum with the potential to enhance quantitative analysis, particularly for complex samples. The resulting improvement in total signal strength and reduction in the coefficient of variation (from 31.1% to 5.2% for microcystin‐LR) further enhance the potential for sensitive and accurate quantitation. Other potential additives tested, including 18‐crown‐6 ether, alkali metal salts (lithium chloride, sodium chloride, potassium chloride), and other transition metal salts (silver chloride, silver nitrate, copper(II) nitrate, copper(II) sulfate, zinc acetate), were unable to achieve comparable results. Application of this technique to the analysis of several microcystins, potent peptide hepatotoxins from cyanobacteria, is illustrated. Copyright © 2007 John Wiley & Sons, Ltd.
Fragmentation study on butanolides with tandem mass spectrometry and its application for the screening of ScbR‐captured quorum sensing molecules in Streptomyces coelicolor A3(2)
Authors: Joo Hwang‐Soo , Yang Yung‐Hun , Lee Chang‐Soo , Kim June‐Hyung , Kim Byung‐Gee
Published: February 2007

Streptomyces coelicolor has a quorum sensing (QS) system triggered by small diffusible signaling molecules, i.e. butanolides (or γ‐butyrolactones) and their cognate DNA‐binding receptors. Using the DNA‐binding receptors as an affinity capture matrix, the butanolides can be easily enriched and identified. For the identification and screening of the butanolides, the diagnostic peak lists generated by the tandem mass spectrometric (MS/MS) fragmentation analysis of chemically synthetic butanolides were used. In the case of using ScbR as the capture matrix, SCB1, a previously well‐known butanolide, and Acl‐1 (or SCB3)‐type butanolides having one more carbon in the acyl chain than SCB1, were detected. This is the first report directly demonstrating that Acl‐1 is able to bind to ScbR in S. coelicolor. Our proposed method using both diagnostic peak lists of butanolide and the purified receptor protein as an affinity capture tool can be applied to rapidly screen QS molecules in vitro. Copyright © 2007 John Wiley & Sons, Ltd.
Ecological effects of groundwater pumping and a natural drought on the upper reaches of a chalk stream
Authors: Wright J. F. , Berrie A. D.
Published: February 2007

The ecological effects are examined of a three‐month test of a groundwater pumping scheme, which augmented flow in a chalk stream in autumn 1975. The impact on the macrophytes and invertebrates in the upper perennial stream which received pumped water were found to be minimal.

After pumping ceased, a dry winter and spring led on to a major drought in summer 1976. This prompted operational use of the groundwater pumping scheme in late summer 1976 prior to heavy winter rains which resulted in a return to the normal pattern of discharge in 1977. The ecological effects of the drought, the operational pumping and its aftermath are assessed on three channel reaches: the intermittent zone of the stream, which remained dry throughout 1976; the upper perennial channel where changes in flow regime were most severe; and the lower perennial section of the stream.

Drying of the intermittent section for over one year had more severe effects on the invertebrates and fish populations than on the macrophytes, which recovered rapidly after the return of flow. In the upper perennial section, the drought led to siltation of the river‐bed, loss of macrophytes and limited habitat diversity for the invertebrate fauna. Further downstream, effects were still detectable, though less severe.

Operational pumping brought immediate benefit to the perennial stream by increasing the river width, removing silt and encouraging growth of macrophytes, which provided habitat and food resources for invertebrates. However, in the upper perennial reach, where siltation and loss of macrophytes had been severe, regrowth of macrophytes was slow and the effects of the drought on both macrophytes and invertebrates were still apparent in autumn 1977. It is proposed that a pumping policy that maintains river flow above the level at which siltation and subsequent loss of macrophytes occurs could minimize undesirable ecological effects of extreme low flows.
Channel degradation in the middle Arve river, France
Authors: Peiry J.‐L.
Published: February 2007

Man‐induced channel changes within Alpine alluvial rivers are investigated. For the middle Arve river, a series of long profiles surveyed between 1856 and 1981 show deep and rapid degradation since the beginning of the 1950s. This tendency is related to gravel extraction, weir construction, and embankment, and is shown to characterize Alpine rivers.
Accumulation of fine sediment within substrate gravels along two regulated rivers, UK
Authors: Petts Geoffrey E.
Published: February 2007

The channel‐bed materials have a marked influence on the biota of lotic systems. Experimental studies suggest that flow regulation, specificially the reduction in magnitude of flood events, may lead to the infiltration of fine particles into, and the concentration of these sediments within, open framework gravels downstream from tributary sediment sources. This paper examines the distribution of fines (sub‐2 mm), within channel substrate gravels along two regulated rivers in upland Britain.

Bulk‐ and freeze‐sample techniques were used: the latter yielded volumes of fines five times those of the former. This emphasizes the problem of wash‐out during bulk‐sample collection, especially in compact, coarse gravel substrates. Nevertheless, the same spatial pattern was revealed by both data sets. Along both regulated rivers, the proportion of the substrate finer than 2 mm exceeds 20 per cent, by weight, below tributary confluences, contrasting with values for non‐regulated sites of less than 5 per cent. Both the amount and size of matrix sediments decrease downstream from the confluences. The spatial scale of the impact is small and the resultant ecological consequences of substrate sedimentation are likely to be localized.
Short communications monitoring the impact of dams on the downstream physical environment in the tropics
Authors: Olofin E. A.
Published: February 2007

In the main, the assessment of environmental impact of dams is not undertaken in feasibility surveys of dam‐related projects in the Tropics, as it should. Consquently, post‐implementation investigations (mostly by research students) continue to reveal undersirable effects. The lack of appropriate data on which to base predictions in proposed projects, or to assess environmental impacts in ongoing ones, is a major problem. It is argued that continuous monitoring of existing projects can help to fill this data gap. Such monitoring should cover the entire basin affected, taking into account environmental variables of the upstream, reservoir, and downstream systems. This paper considers the downstream system. Variables of importance include: soil erosion and sediment yield; channel morphometry; discharge and runoff pattern and volume; and changes in vegetation cover, water chemistry and water quality. Field measurements and observations, laboratory analyses, and statistical inferences are required to yield acceptable results. Such results are expected to enhance a better understanding (through impact assessment) and management of existing projects, on the one hand, and to aid wise predictions (at the feasibility stage) of environmental effects of new projects, on the other.
Historical changes of a large river in an urban area: The Garonne river, Toulouse, France
Authors: Fortuné M.
Published: February 2007

Man‐made structures have greatly modified the flow pattern of the Garonne River at Toulouse (France) since at least the 12th century. The first of many small dams was constructed in 1182. Destructive floods regularly destroyed the dams, flooded protions of the city, changed the river course, and destroyed the wooden bridges, the first of which was probably built during the first half of the 13th century. The first stone bridge was completed in 1660, after a 100 year period of constuction.

After 1680 attempts to control the river led to a variety of river responses: increased sedimentation in some locations and erosion in others, a reduction in the number of islands from seventeen to four, and a 63 per cent reduction in the length of shoreline in the urban area of Toulouse.
Water quality management: A regional perspective— The severn‐trent area
Authors: Brewin D. J. , Martin J. R.
Published: February 2007

The management of water quality in U.K. rivers is going through a period of major change due to the proposed reorganization of the water industry and to the increasing demands on river resources and the imposition of stricter environmental standards. Changes to the river classification scheme and effluent consent conditions are discussed. A brief summary is given of some of the quality problems that are of particular concern in the Severn‐Trent area. The impact on quality of river regulation including in‐river purification lakes is described. Catchment models have been developed to assist with the management of river resources. These and other river quality modelling techniques are reviewed.
Regulation of the River Dee
Authors: Lambert Allan
Published: February 2007

This paper discusses the interdisciplinary approach statutorily adopted for the management of the intensively regulated River Dee. The role of the Dee Consultative Committee is discussed and the procedures and methods for river regulation are described. Particular problems arise during severe droughts and a Conservation Rule Curve, using the aggregated storage of the two main reservoirs, has been devised to act as the trigger for optional initiation of water conservation measures. The social and environmental benefits of the integrated management scheme are demonstrated. Areas of conflict have been, and must continue to be, resolved by consultation, cooperation, and compromise.
Regulating the River Severn
Authors: Douglas J. R.
Published: February 2007

The River Severn is the longest of Britain's regulated rivers: this chapter describes the geography of the river's catchment area, from its source in central Wales to the Bristol Channel where it flows into the sea. It then considers the historical development of the Severn as a water resource, culminating in the construction of Llyn Clywedog and more recently the Shropshire Groundwater Scheme to augment low river flows and support greatly increased abstractions. Plans for even more substantial development of the resource system appropriate to the rapid demand growth of the 1960s and early 1970s are discussed. Practical experience in regulating flows in the river gained during the drought of 1976 is described and used to explain recent developments in the practice and monitoring of river regulation.
Hydrological changes and river regulation in the UK
Authors: Higgs Gary , Petts Geoff
Published: February 2007

Water levels of streams and rivers in the United Kingdom have been regulated by weirs for more than one thousand years, but regulation of the flow regime by impoundments began in the latter half on the 19th Century. Organized river flow measurements were not undertaken until 1935, and today the average record length is about 20 years. Only three gauging stations have provided data suitable for pre‐ and post‐impoundment comparisons. Other studies have relied on the comparison of regulated and naturalized discharges. In either case climate and land‐use changes make evaluation of the hydrological effect of impoundments problematic. This paper reviews research on hydrological changes due to river regulation in the UK, and presents a case study of the River Severn to evaluate the influence of Clywedog Reservoir on flood magnitude and frequency.

Consequent upon dam completion, on average, median flows have been reduced by about 50per cent; mean annual floods have been reduced by about 30per cent; and low flows have been maintained at about 22 per cent higher than the natural Q95 discharge. However, marked differences exist between rivers. The direct effect of reservoir compensation flows and the indirect effect of inter basin transfers for supply have significantly increased minimum flows in most rivers, although in the case of the latter this involves the discharge of treated effluents. In contrast, the effects of impoundments on flood magnitude and frequency is less clear and on the River Severn, at least, changes in flood hydrology during the past two decades are shown to be more related to climate change than to river regulation.
Assessment of the water surface profile model: Accuracy of predicted instream fish habitat conditions in low‐gradient, warmwater streams
Authors: Osborne Lewis L. , Wiley Michael J. , Larimore R. Weldon
Published: February 2007

The Instream Flow Group's (U.S. Fish and Wildlife Service) Physical Habitat Simulation (PHABSIM) model, the major component of the incremental methodology (IFIM) is presently the most widely employed instream flow assessment procedure. PHABSIM consists of both biological and hydrological components. The Water Surface Profile (WSP) hydrologic model is commonly recommended and employed in many PHABSIM applications. While several recent studies have critically addressed and questioned the validity of PHABSIM as a management tool from a biological perspective, there has been surprisingly limited attention given to problems of use, accuracy, bias, and the effect of errors in the WSP hydraulic simulation on the final PHABSIM output (i.e. weighted usable area (WUA) estimates). Therefore, the purpose of this study was to examine the effectiveness of the WSP hydraulic model for predicting hydraulic conditions in low‐gradient, warmwater streams in east‐central Illinois. Attempts were made to calibrate the WSP model at four locations on the Salt Fork and Middle Fork rivers and compare simulated results to actual measured conditions at different discharges. We conclude that in low‐gradient warmwater streams, the WSP model: (1) does not adequately simulate low‐flow habitat conditions, due to an inability to calibrate the model; (2) is, at best, difficult to calibrate, even within hydraulically uniform channels; (3) requires several field measurements and calibrations to simulate a sufficiently wide range of naturally occurring flows: (4) provides poor estimates of cell depth and velocity; and, results in highly erratic and often poor estimates of WUA for adults and fry of smallmouth bass. Finally, our results indicate that similar or better estimates of actual WUA can be attained by monitoring the distributions of depth, velocity, and substrate at a series of representative transects at different discharges and interpolating WUA from observed field data using less expensive and time consuming regression models.
Mitigation, compensation, and future protection for fish populations affected by hydropower development in the upper Columbia system, Montana, U.S.A.
Authors: Fraley John , Marotz Brian , Decker‐Hess Janet , Beattie Will , Zubik Ray
Published: February 2007

Pursuant to the Northwest Power Planning Council's Fish and Wildlife Program for the Columbia River system, we estimated losses in fish populations and developed mitigation, compensation, and protection alternatives for reservoirs and downstream river reaches affected by hydropower development in the Flathead and Kootenai River systems in northwest Montana, U.S.A. The construction of Hungry Horse Dam has resulted in estimated annual losses of 65500 migratory juvenile westslope cutthroat and 1965 adult migratory bull trout from the Flathead Lake and River system. In addition, operations of Hungry Horse and Kerr dams caused annual losses conservatively estimated at 96300 river‐spawning and 131000 lakeshore‐spawning kokanee adults. Water level fluctuations caused by dam operations at Libby and Hungry Horse reservoirs result in: (1) altered thermal stratification, (2) indirect losses in phytoplankton and zooplankton production, (3) direct washout of phytoplankton and zooplankton through dam penstocks, (4) reductions in standing crop of benthic organisms and of insects on the water surface, and (5) reduced fish growth in the late summer and fall. Mitigative measures include: (1) 99.2 and 113.3 m3 s−1 minimum flows in the Flathead and Kootenai rivers respectively, to protect salmonid eggs and juveniles, (2) improvement of fish passage to restore migrations between the Flathead and Swan systems, and (3) biological rule curves for operations at Libby and Hungry Horse reservoirs. To compensate for fisheries losses, we recommend enhancement of spawning and rearing habitat, introductions of hatchery juveniles, and spawning channels. We recommend protection from further hydropower development for 100 stream reaches (1386 km) for fish species of special concern, and for outstanding sport fisheries. These and other measures will be considered by various agencies in developing an overall fisheries restoration plan which should be flexible, and employ principles of adaptive management. Effectiveness of the plan may be limited by heavy reliance on hatchery fish. Although mitigation efforts may not restore fish populations to pre‐dam levels, substantial benefits should be realized.
Responses of the sediment system of a regulated river to a scour valve release: Llyn Clywedog, mid‐Wales, U.K.
Authors: Leeks G. J. L. , Newson M. D.
Published: February 2007

In March 1985 engineering tests of scour valves at the base of the Llyn Clywedog regulating reservoir resulted in a controlled peak release discharge of 53m3 s−1 into regulated reaches of the upper Severn. To exploit this unusual opportunity, simple monitoring systems were set up within the first 50 km downstream to assess the morphological effects on bed and banks and the movement of bed and suspended sediments. The interpretation of suspended sediment transport patterns became the major analytical task following the release, since bedload and morphological impacts were minimal. In comparison with natural floods, the scour valve release exhibited suspended sediment concentrations usually associated with a five‐year event, but with a complex time and space pattern resulting from the release strategy. Wet antecedent conditions and the short duration of the scour valve release help to explain why impacts on the downstream channel were, otherwise, much more restricted than those of a water resource test release in 1975. Since scour releases can be planned with greater flexibility than major water resource releases, indications are that they should be made ‘on the back of’ natural high flows, although sensitive sites may require protection.
Proposals for inhibiting abundant phytoplankton growth at the head of a river reservoir
Authors: Kagawa H.
Published: February 2007

In a river reservoir, the Ishitegawa Dam Reservoir in Japan, sites of abundant phytoplankton growth were investigated in connection with the water movement in the reservoir from January 1982 to January 1984 by comparing the distributions of chlorophyll a, water temperature, and coliform bacteria (Project A). The results distinguished three types of phytoplankton growth, of which one type, the abundant surface growth at the head of the reservoir, was most frequently observed. This case was considered to be caused by mixing of the surface lake water with the inflowing nutrient‐rich river water at the shallow lake‐head. Subsequently the effects of dissolved calcium and magnesium on the chlorophyll a and phytoplanktonic particulate phosphorus concentrations at the head of the reservoir were investigated until December 1987 (Project B). A trophic index, named the Ca‐Mg index, was found which correlated positively with the chlorophyll a and phytoplanktonic particulate phosphorus concentrations in a logarithmic scale and varied in relation to the changes in the same index of the inflowing river water. Based on the ecological results of these two projects, two proposals are presented for inhibiting abundant phytoplankton growth at the head of a river reservoir. Proposal A: make the head deep and, in addition, create a strong near‐bottom underflow of the inflowing river water. Proposal B: make a bypass in order to cut off the inflow of river water in the case of a high Ca‐Mg index.
Measuring discontinuities in the ter river
Authors: Sabater F. , Armengol J. , Sabater S.
Published: February 2007

In this paper a method for measuring discontinuities in the spatial organization of a river produced by disturbances is presented. First of all, a way of doing comparable environmental gradients defined by different variables is proposed. To do so, all the variables have been transformed by means of the equation: Pi' = Pi ‐ Pmin/Pmax ‐ Pmin, as a previous measure of the parametric distances (Pij') between sites. When these parametric distances are plotted in relation to the geographical ones, the distortion between both river images appears as an expression of the changes occurring in each stretch, and the derivative dPij'/dx is a measure of its rate of change. To define a river gradient, we need to calculate the general trend of a variable, using direct gradient analysis. The fit of the results obtained from an undisturbed stretch to an empirical curve for all the river gives us a measure of the expected values for that river. The difference between expected and observed values can be a measure of the discontinuity. The same procedure has been used for an overall environmental and biological data. To this end, the Euclidean distance (ED) and a distance obtained from Factor score of a Principal Components analysis (PCA) have been calculated. Only the second method seems to be of general interest for studying discontinuities. Finally, the results of the first score loadings obtained from PCA of three groups of variables (physical and chemical, physiographical and morphological, and phytobenthic) have been used to do a comparison between the parametric images of the River Ter.
A study of physical parameters at the spawning sites of the european grayling (Thymallus thymallus L.)
Authors: Gönczi Adam P.
Published: February 2007

An investigation of the spawning sites of European grayling, Thymallus thymallus (L.), in two Swedish rivers revealed narrow range in their physical parameters.

The bottom substrate was composed of 10–20 per cent sand, 50–70 per cent gravel (<2cm), 20–30 per cent stones (2–10cm), and a few bigger stones (>10cm in diameter). Eggs were found only where the gravel thickness was more than 5 cm. The depth varied between 30–50cm. Mean depth for 22 different spawning sites was 36cm. The water velocity varied between 23–90cm s−1, average 54 cm s−1. The temperature at the start of spawning was 3.9°C and at the end it was about 9°C.

The results indicate the narrow range in physical parameters at the spawning sites. Small changes in the environment caused by regulation of river flow or water level may disturb the spawning behaviour of grayling and cause a decrease in population size or even extinction.
Flushing flow recommendations for maintenance of salmonid spawning gravels in a steep, regulated stream
Authors: Reiser Dudley W. , Ramey Michael P. , Beck Stuart , Lambert Thomas R. , Geary R. Eugene
Published: February 2007

A study was conducted to develop flushing flow recommendations for maintaining the quantity of salmonid spawning gravels in the North Fork of the Feather River, a regulated stream in California, U.S.A. This required the development of a technique which would prescribe flows to remove sediments from the gravels without removing the gravels themselves, which are in finite supply in the river.

Field studies involved the use of a ‘two‐point‐are’ procedure which allowed depth, velocity, and substrate measurements to be concentrated over spawning gravels at each site. Measurements were repeated at each site at three different flows ranging from 1.7 to 11.3 m3 s−1. The local velocity and depth measurements were used to evaluate hydraulic conditions within areas containing spawning gravels. Four flow levels were derived which would provide varying degrees of sediment transport and flushing; (1) surficial flushing of gravels; (2) mobilization of gravels; (3) surficial flushing of cobbles; and (4) mobilization of cobbles.

Results of the study indicated a flushing flow of 56.6 m3 s−1 occurring as a planned release or natural flow for from 1–3 days would be sufficient to transport sediment from spawning gravels. This flow was intermediate to levels which maximize surficial gravel flushing and levels which maximize surficial cobble flushing.
Development of habitat suitability criteria for trout in small streams
Authors: Lambert Thomas R. , Hanson David F.
Published: February 2007

We observed 2863 trout in the wild to determine habitat utilization in small streams of the Kings River basin in California's Sierra Nevada mountains. The habitat utilization data were used to develop habitat suitability functions that provide input variables to the instream flow incremental methodology (IFIM) habitat assessment model of the U.S. Fish and Wildlife Service.

Observations of habitat utilization of rainbow trout (Salmo gairdneri), brown trout (Salmo trutta), and brook trout (Salvelinus fontinalis) were obtained during the summer months of 1983 and 1984. The observations were made in small streams with discharges ranging from 0.7 m3 s−1 to 0.03 m3 s−1. The streams are at elevations of 1250 to 2530 m. Equal effort was applied to observing undisturbed trout in all habitat types. Snorkeling proved to be the most effective method of observation.

Individual trout of all species and life stages were most often observed in the lower half of the water column, utilizing low‐velocity currents of less than 3.0 cm s−1.

From the depth and velocity utilization data, several forms of habitat suitability functions were developed and evaluated:

Univariate depth and velocity functions derived from frequency histogram analysis.

Univariate depth and univariate velocity exponential polynomial models.

Bivariate depth and velocity exponential polynomial models.

Univariate exponential polynomial models provided the best fit to the data for each species, based on visual comparisons of response surfaces and contour plots, and comparisons of computed sums of squared errors. Bivariate models fitted to the data resulted in greater sums of squared errors than multiplicative aggragation of univariate models, and frequently predicted utilization at zero depth.

The habitat suitability functions derived from the univariate exponential polynomial models provided the best input to the IFIM habitat assessment models.