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Kinds of Metres Selected AbstractsGrapevine dormant pruning weight prediction using remotely sensed dataAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2003S.Z. DOBROWSKI Abstract Aerial image analysis was utilised to predict dormant pruning weights between two growing seasons. We utilised an existing in-row spacing trial in order to examine the relationship between dormant pruning weights and remotely sensed data. The experimental vineyard had a constant between-row spacing (2.44 m) and five different in-row spacings (0.91, 1.52, 2.13, 2.74 and 3.35 m) resulting in spatial variation in canopy volume and dormant pruning weights (kg/metre of row). It was shown that the ratio vegetation index (NIR/R) was linearly correlated with field-wide measurements of pruning weight density (dormant pruning weight per metre of canopy) for both the 1998 and 1999 growing seasons (r2= 0.68 and 0.88, respectively). Additionally, it was shown that the regression parameters remained consistent between the two growing seasons allowing for an inter-annual comparison such that the vegetation index vs canopy parameter relationship determined for the 1998 growing season was used to predict field-wide pruning weight densities in the 1999 growing season prior to harvest. [source] Field mapping and digital elevation modelling of submerged and unsubmerged hydraulic jump regions in a bedrock step,pool channelEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2006Brett L. Vallé Abstract High-resolution tacheometric field surveying was integrated with computer-assisted drafting to visualize and contrast three-dimensional bed and water surface digital elevation models (DEMs) for submerged and unsubmerged hydraulic jump regions in a bedrock step,pool channel. Measurements were conducted for two discharge conditions. Since previous applica-tions of three-dimensional field mapping and digital elevation modelling of stream channels have been limited to smoothly contiguous gravel-bedded systems, surveying was optimized by topographic setting and scaled to localized bed and water surface discontinuities. Traces and visualizations of the jump regions indicated that dichotomous decimetre shifts in water surface topography occurred for both jump regions from lower to higher discharges. Systematic removal of the survey points and DEM differencing indicated that point densities of ten points per square metre, in conjunction with a survey structure targeting grade breaks of 0·3,0·5 m, were required to capture decimetre form variations of the natural jump regions. The DEMs highlight the importance of recognizing the relationship between transcritical flow structures and localized topographic heterogeneities in bedrock channels. Copyright © 2006 John Wiley & Sons, Ltd. [source] Women's traditional fishery and alternative aquatic resource livelihood strategies in the Southern Cameroonian RainforestFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2010R. E. BRUMMETT Abstract, To inform the development of alternative livelihoods, the women's traditional alok fishery in the Campo-Ma'an National Park and buffer zone of southern Cameroon were studied over 15 months. Participatory rural appraisal was used to characterise livelihood strategies among 45 households. Thirty-three cultured crops, nine farmed animal species and 65 non-timber forest products, including 31 bushmeat species are cultivated in, or harvested from, the forest. Transport is a major impediment to commercial trade of all local products. In 16 alok fishing events, average weight of fish harvested was 5.14 kg per 280 m of stream distributed among an average of 23 fishers for a return of 220 g person,1 or 40 g fish h,1 over 5 h of work. Fish and crustacean standing stock was 25 g per linear metre or 167 t when extrapolated to the zone. Implications for rainforest livelihoods in light of the Millennium Development Goals are discussed. [source] Occurrence of Heterobasidion basidiocarps on cull pieces of Norway spruce left on cutting areas and in mature spruce standsFOREST PATHOLOGY, Issue 6 2007M. M. Müller Summary Fruiting of Heterobasidion on cull pieces and stumps of Norway spruce was investigated in cutting areas and mature spruce stands located in southern Finland. Cull pieces of variable size and showing butt rot were left on three clear-cut areas and in one thinned stand. Additionally, a part of the cull pieces was transported to mature forest sites with closed canopy. During the succeeding 3,4 years the cull pieces were investigated annually for sporocarps of Heterobasidion, and the area of actively sporulating pore layer of each sporocarp was measured. Root bases of spruce stumps in the logging areas were excavated and sporocarps found on the stumps also measured. At the onset of the experiment, Heterobasidion spp. were isolated from 76% of the cull pieces showing butt rot; 85% of the isolates were identified as H. parviporum and 15% as H. annosum s.s. During the following 3,4 years sporocarps were found on 20% of the 1938 cull pieces where Heterobasidion butt rot was initially detected visually. Sporocarp formation was promoted by advancement of butt rot, increasing cull piece diameter and end-to-end ground contact, but restricted by the colonization of the cull piece by Stereum sanguinolentum. Between-site differences were significant but could not be explained by differences in tree cover. At the end of the investigation period the average sporulating area of Heterobasidion sporocarp per metre of cull piece was higher than the average sporulating area per stump at three of four logging sites. Hence, leaving cull pieces containing Heterobasidion butt rot at logging areas in southern Finland can considerably increase local production of Heterobasidion spores. [source] Critical periods in the life cycle and the effects of a severe spate vary markedly between four species of elmid beetles in a small streamFRESHWATER BIOLOGY, Issue 8 2006J. M. ELLIOTT Summary 1. The chief objectives were: (i) to describe quantitatively the life cycles of four species of Elmidae, Elmis aenea, Esolus parallelepipedus, Oulimnius tuberculatus and Limnius volkmari; (ii) to use life tables to identify critical periods for survival in the life cycle of each species; (iii) to evaluate the immediate and longer-term effects of a severe spate on densities of the four species. Monthly samples were taken over 63 months at two contrasting sites in a small stream: one in a deep section with macrophytes abundant, and the other in a shallow stony section. 2. There were five larval instars for O. tuberculatus, seven for L. volkmari and six for the other two species. The life cycle of each species took 1 year from egg hatching (chiefly in June for E. aenea and O. tuberculatus, and July for the other species) to pupation in the stream bank and a further year before the adults in the stream matured and laid their eggs. Mature adults were present in most months, but were rare or absent in January and February and attained maximum densities in April for O. tuberculatus and May for the other species. 3. Laboratory experiments provided data on egg hatching and pupation periods and the number of eggs laid per female. Life tables compared maximum numbers per square metre for key life-stages. Within each species, mortality rates between adjacent life-stages were fairly constant among six cohorts and between sites, in spite of large differences in numbers. The only exception for all species was the high adult, but not larval, mortality during a severe spate. 4. Standardised life tables, starting with 1000 eggs, identified key life-stages with the highest mortality, namely the early life-stages for E. aenea (36% mortality), start of the overwintering period to pupation for O. tuberculatus (41%) and L. volkmari (51%), start of pupation to the maximum number of immature adults for E. parallelepipedus (41%) and between the maximum numbers of immature and mature adults for O. tuberculatus (41%). Therefore, critical periods for survival in the life cycle differed between species, presumably because of their different ecological requirements. Similarly, the effects of the spate on adult mortality, and hence egg production, varied between species, being most severe and long-term for E. aenea and O. tuberculatus, less severe for E. parallelepipedus and least severe with a rapid recovery for L. volkmari. Possible reasons for these discrepancies are discussed, but more data are required on the food and microhabitat requirements of the elmids before satisfactory explanations can be found. [source] Respiration and annual fungal production associated with decomposing leaf litter in two streamsFRESHWATER BIOLOGY, Issue 9 2004M. D. Carter Summary 1. We compared fungal biomass, production and microbial respiration associated with decomposing leaves in one softwater stream (Payne Creek) and one hardwater stream (Lindsey Spring Branch). 2. Both streams received similar annual leaf litter fall (478,492 g m,2), but Lindsey Spring Branch had higher average monthly standing crop of leaf litter (69 ± 24 g m,2; mean ± SE) than Payne Creek (39 ± 9 g m,2). 3. Leaves sampled from Lindsey Spring Branch contained a higher mean concentration of fungal biomass (71 ± 11 mg g,1) than those from Payne Creek (54 ± 8 mg g,1). Maximum spore concentrations in the water of Lindsay Spring Branch were also higher than those in Payne Creek. These results agreed with litterbag studies of red maple (Acer rubrum) leaves, which decomposed faster (decay rate of 0.014 versus 0.004 day,1), exhibited higher maximum fungal biomass and had higher rates of fungal sporulation in Lindsey Spring Branch than in Payne Creek. 4. Rates of fungal production and respiration per g leaf were similar in the two streams, although rates of fungal production and respiration per square metre were higher in Lindsey Spring Branch than in Payne Creek because of the differences in leaf litter standing crop. 5. Annual fungal production was 16 ± 6 g m,2 (mean ± 95% CI) in Payne Creek and 46 ± 25 g m,2 in Lindsey Spring Branch. Measurements were taken through the autumn of 2 years to obtain an indication of inter-year variability. Fungal production during October to January of the 2 years varied between 3 and 6 g m,2 in Payne Creek and 7,27 g m,2 in Lindsey Spring Branch. 6. Partial organic matter budgets constructed for both streams indicated that 3 ± 1% of leaf litter fall went into fungal production and 7 ± 2% was lost as respiration in Payne Creek. In Lindsey Spring Branch, fungal production accounted for 10 ± 5% of leaf litter fall and microbial respiration for 13 ± 9%. [source] The creation of an asymmetric hydraulic fracture as a result of driving stress gradientsGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2009T. Fischer SUMMARY Hydraulic fracture stimulation is frequently performed in hydrocarbon reservoirs and geothermal systems to increase the permeability of the rock formation. These hydraulic fractures are often mapped by hypocentres of induced microearthquakes. In some cases microseismicity exhibits asymmetry relative to the injection well, which can be interpreted by unequal conditions for fracture growth at opposite sides of the well or by observation effects. Here we investigate the role of the lateral change of the minimum compressive stress. We use a simple model to describe the relation among the lateral stress gradient, the mean viscous pressure gradients in the fracture wings, the fracture geometry, and the net pressure in the fracture. Our model predicts a faster fracture growth in the direction of decreasing stress and a limited growth in the opposite direction. We derive a simple relationship to estimate the lateral stress gradient from the injection pressure and the shape of the seismic hypocentre cloud. The model is tested by microseismic data obtained during stimulation of a Canyon Sands gas field in West Texas. Using a maximum likelihood method we fit the parameters of the asymmetric fracture model to the space,time pattern of hypocentres. The estimated stress gradients per metre are in the range from 0.008 to 0.010 times the bottom-hole injection overpressure (8,10 kPa m,1 assuming the net pressure of 1 MPa). Such large horizontal gradients in the order of the hydrostatic gradient could be caused by the inhomogeneous extraction of gas resulting in a lateral change of the effective normal stress acting normal to the fracture wall. [source] 3D imaging of a reservoir analogue in point bar deposits in the Ferron Sandstone, Utah, using ground-penetrating radarGEOPHYSICAL PROSPECTING, Issue 3 2004Xiaoxian Zeng ABSTRACT Most existing reservoir models are based on 2D outcrop studies; 3D aspects are inferred from correlation between wells, and so are inadequately constrained for reservoir simulations. To overcome these deficiencies, we have initiated a multidimensional characterization of reservoir analogues in the Cretaceous Ferron Sandstone in Utah. Detailed sedimentary facies maps of cliff faces define the geometry and distribution of reservoir flow units, barriers and baffles at the outcrop. High-resolution 2D and 3D ground-penetrating radar (GPR) images extend these reservoir characteristics into 3D to allow the development of realistic 3D reservoir models. Models use geometric information from mapping and the GPR data, combined with petrophysical data from surface and cliff-face outcrops, and laboratory analyses of outcrop and core samples. The site of the field work is Corbula Gulch, on the western flank of the San Rafael Swell, in east-central Utah. The outcrop consists of an 8,17 m thick sandstone body which contains various sedimentary structures, such as cross-bedding, inclined stratification and erosional surfaces, which range in scale from less than a metre to hundreds of metres. 3D depth migration of the common-offset GPR data produces data volumes within which the inclined surfaces and erosional surfaces are visible. Correlation between fluid permeability, clay content, instantaneous frequency and instantaneous amplitude of the GPR data provides estimates of the 3D distribution of fluid permeability and clay content. [source] Seasonal patterns in biomass smoke pollution and the mid 20th-century transition from Aboriginal to European fire management in northern AustraliaGLOBAL ECOLOGY, Issue 2 2007David M. J. S. Bowman ABSTRACT Aim, Globally, most landscape burning occurs in the tropical savanna biome, where fire is a characteristic of the annual dry season. In northern Australia there is uncertainty about how the frequency and timing of dry season fires have changed in the transition from Aboriginal to European fire management. Location, In the tropical eucalypt savannas that surround the city of Darwin in the northwest of the Northern Territory of Australia. Methods, Our study had three parts: (1) we developed a predictive statistical model of mean mass (µg) of particulates 10 µm or less per cubic metre of air (PM10) using visibility and other meteorological data in Darwin during the dry seasons of 2000 and 2004; (2) we tested the model and its application to the broader air shed by (a) matching the prediction of this model to PM10 measurements made in Darwin in 2005, (b) matching the predictions to independent measurements at two locations 20 km to the north and south of Darwin and (c) matching peaks in PM10 to known major fire events in the region (2000,01 dry seasons); and (3) we used the model to explore changes in air quality over the last 50 years, a period that spans the transition from Aboriginal to European land management. Results, We demonstrated that visibility data can be used reliably as a proxy for biomass burning across the largely uncleared tropical savannas inland of Darwin. Validations using independent measurements demonstrated that our predictive model was robust, and geographically and temporally representative of the regional airshed. We used the model to hindcast and found that seasonal air quality has changed since 1955, with a trend to increasing PM10 concentrations in the early dry season. Main conclusions, The results suggest that the transition from Aboriginal to European land management has been associated with an increase in fire activity in the early months of the dry season. [source] Growth and Yield Response of Facultative Wheat to Winter Sowing, Freezing Sowing and Spring Sowing at Different Seeding RatesJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2006A. Ozturk Abstract Growth and yield of wheat are affected by environmental conditions and can be regulated by sowing time and seeding rate. In this study, three sowing times [winter sowing (first week of September), freezing sowing (last week of October) and spring sowing (last week of April)] at seven seeding rates (325, 375, 425, 475, 525, 575 and 625 seeds m,2) were investigated during the 2002,03 and 2003,04 seasons, in Erzurum (Turkey) dryland conditions, using Kirik facultative wheat. A split-plot design was used, with sowing times as main plots and seeding rates randomized as subplots. There was a significant year × sowing time interaction for grain yield and kernels per spike. Winter-sown wheat produced a significantly higher leaf area index, leaf area duration, spikes per square metre, kernel weight and grain yield than freezing- and spring-sown wheat. The optimum time of sowing was winter for the facultative cv. Kirik. Grain yields at freezing and spring sowing were low, which was largely the result of hastened crop development and high temperatures during and after anthesis. Increasing seeding rate up to 525 seeds m,2 increased the spikes per square metre at harvest, resulting in increased grain yield. Seeding rate, however, was not as important as sowing time in maximizing grain yield. Changes in spikes per square metre were the major contributors to the grain-yield differences observed among sowing times and seeding rates. Yield increases from higher seeding rates were greater at freezing and spring sowing. We recommended that a seeding rate of 525 seeds m,2 be chosen for winter sowing, and 575 seeds m,2 for freezing and spring sowing. [source] Contrasting interference functions and foraging dispersion in two species of shorebird (Charadrii)JOURNAL OF ANIMAL ECOLOGY, Issue 2 2000Michael G. Yates Summary 1.,Above a threshold density of , 100 birds ha -1, strong interference occurred between redshank Tringa totanus (Linnaeus) feeding by sight on the amphipod crustacean Corophium volutator (Pallas). No aggressive interactions occurred between the birds and the probable cause was prey depression. 2.,Redshank fed in a square metre of mud that had recently been exploited by another redshank much less often than would be expected by chance. By avoiding areas where prey would have been recently exploited, the feeding rate of redshank was up to three times faster than it would have been had they not avoided other foraging redshank. 3.,Bar-tailed godwit fed in a square metre of mud that had been recently exploited by another godwit much more often than would be expected by chance in randomly moving birds. They tended to flock while foraging and showed no tendency to avoid areas where prey would have been recently exploited. 4.,There was no evidence that interference occurred between bar-tailed godwit Limosa lapponica (Linnaeus) feeding on the polychaete lugworm Arenicola marina (Linnaeus) at densities below 300 birds ha -1, even though aggressive interactions occurred between birds. [source] Controlling western corn rootworm larvae with entomopathogenic nematodes: effect of application techniques on plant-scale efficacyJOURNAL OF APPLIED ENTOMOLOGY, Issue 5 2010S. Toepfer Abstract The three larval instars of western corn rootworm (Diabrotica virgifera virgifera LeConte, Coleoptera: Chrysomelidae) feed on the roots of maize, Zea mays (L.). The effects of six application techniques on the plant-scale efficacy of the entomopathogenic nematode species, Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae), in controlling D. v. virgifera populations were assessed in seven field plot experiments in southern Hungary between 2004 and 2007. Approximately 230 000 nematodes were applied per row metre using four different stream spray techniques; or, alternatively 400 000 nematodes per square metre using two different flat spray techniques. Nematode efficacy was assessed by comparing the number of emerging adult D. v. virgifera, and root damage between treatments and untreated controls. All tested nematode application techniques reduced D. v. virgifera density by at least 50% (on average across fields and years). The highest reduction in D. v. virgifera density was 68% and occurred when nematodes were applied into the soil together with maize sowing using a fluid solid stream. Rainfall, the day before application likely increased the control efficacy of H. bacteriophora. Using the 0.00,3.00 node injury damage rating scale, we estimated that potential root damage was prevented by 25,79% when H. bacteriophora was applied. Although, H. bacteriophora can effectively be applied with all of the techniques tested, for optimum performance and minimum costs, it is suggested that the nematodes be applied as follows: (i) as a stream requiring 8,10 times less volume of water than flat sprays, or as a granule requiring no water, and (ii) into the soil when sowing maize, requiring less water than soil surface sprays and avoiding the destruction of nematodes by UV radiation and additional machinery use. [source] Micro-organisms and dust exposure in an Italian grain millJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2005C. Dacarro Abstract Aims:, In order to assess possible occupational risk for workers in a grain mill, we evaluated aerial microbiological contamination in different areas of the mill and at different points of the production line. We also measured the concentration of aerodispersed dust particles. Methods and Results:, An assessment of microbiological contamination levels based on a Global Index of Microbial Contamination per cubic metre (GIMC per m3), an Index of Mesophilic Bacterial Contamination, and an Amplification Index is proposed. The indices were obtained from total and fungal counts. The cleaning sector is the most contaminated area of the mill: the mean GIMC per m3 was 17 213·6. In this area, the average microbial contamination was 11·41 times higher than that in the external environment. The highest concentrations of aerodispersed dust (inhalable 2·763 mg m,3; respirable 1·400 mg m,3) were found in the cleaning area. Conclusions:, The proposed microbiological indices and the concentrations of aerodispersed dust particles show that the most hazardous section of the mill is the cleaning area. The large variation in the data does not depend on seasonal factors, but rather on not easily identifiable conditions of the internal environment which facilitate diffusion and/or proliferation of the micro-organisms. Significance and Impact of the Study:, The proposed microbiological contamination indices and the evaluation of the concentration of dust particles allow the identification of critical positions during the production cycle so that suitable measures to prevent the aerial contamination can be taken. [source] Forest progression modes in littoral Congo, Central Atlantic AfricaJOURNAL OF BIOGEOGRAPHY, Issue 9 2004Charly Favier Abstract Aim, To understand the persistence of a forest,savanna mosaic in places where rainfall data suggest that forest take-over should take place. To study the various modes of forest encroachment, and the role of human activities to hamper it. Location, Data were collected on several forest,savanna ecotones in the coastal region of the Republic of Congo. The sites were chosen to illustrate the differing principal modes of forest expansion, corresponding to different levels of anthropic pressure. Methods, The study sites were situated on five transects perpendicular to the ecotone (total sampled area: 1.7 ha) and 10 forest clumps in savanna (with diameters from 3 to 20 m). Along the transects botanical identification, diameter measurement and cartography were performed, while leaf area index was measured at a high resolution (every metre) along two of them. Collected data were analysed using a continuous quantification approach, which is much more useful than classical quadrat analysis. Time calibration of progression rates was performed using a simple model of the growth of the characteristic pioneer species, Aucoumea klaineana. Results, The two main different modes are reflected in different successional patterns. The edge diffusion is slow (its rate is evaluated to c. 1 m year,1) and is characterized by a progressive increase in large-diameter tree density and shade-tolerant tree density away from the ecotone. Conversely, savanna to forest phase transition by coalescence of clumps exhibits high tree density remnants distributed in established forest. The composition of these remnants is compatible with that of the forest clumps in savannas. Main conclusions, Three functional groups of pioneer trees are distinguished: some occupy the edge (edge pioneer), others establish clumps of forest in savanna (clump pioneers) and the longer-living A. klaineana ensures the transition to ,mature' forest. The two different observed patterns (linear edge progression and clump coalescence) can be understood with the use of a model of forest,savanna dynamics, ,FORSAT'. The two control parameters are the annual rainfall and the frequency of man-made fires in each savanna. In particular, an increase in the fire frequency can lead to a shift from the coalescence regime to the edge progression one. [source] Petrogenesis of lawsonite and epidote eclogite and blueschist, Sivrihisar Massif, TurkeyJOURNAL OF METAMORPHIC GEOLOGY, Issue 9 2006P. B. DAVIS Abstract The Sivrihisar Massif, Turkey, is comprised of blueschist and eclogite facies metasedimentary and metabasaltic rocks. Abundant metre- to centimetre-scale eclogite pods occur in blueschist facies metabasalt, marble and quartz-rich rocks. Sivrihisar eclogite contains omphacite + garnet + phengite + rutile ± glaucophane ± quartz + lawsonite and/or epidote. Blueschists contain sodic amphibole + garnet + phengite + lawsonite and/or epidote ± omphacite ± quartz. Sivrihisar eclogite and blueschist have similar bulk composition, equivalent to NMORB, but record different P,T conditions: ,26 kbar, 500 °C (lawsonite eclogite); 18 kbar, 600 °C (epidote eclogite); 12 kbar, 380 °C (lawsonite blueschist); and 15,16 kbar, 480,500 °C (lawsonite-epidote blueschist). Pressures for the Sivrihisar lawsonite eclogite are among the highest reported for this rock type, which is rarely exposed at the Earth's surface. The distribution and textures of lawsonite ± epidote define P,T conditions and paths. For example, in some lawsonite-bearing rocks, epidote inclusions in garnet and partial replacement of matrix epidote by lawsonite suggest an anticlockwise P,T path. Other rocks contain no epidote as inclusions or as a matrix phase, and were metamorphosed entirely within the lawsonite stability field. Results of the P,T study and mapping of the distribution of blueschists and eclogites in the massif suggest that rocks recording different maximum P,T conditions were tectonically juxtaposed as kilometre-scale slices and associated high- P pods, although all shared the same exhumation path from ,9,11 kbar, 300,400 °C. Within the tectonic slices, alternating millimetre,centimetre-scale layers of eclogite and blueschist formed together at the same P,T conditions but represent different extents of prograde reaction controlled by strain partitioning or local variations in fO2 or other chemical factors. [source] Dosage regimens for inhaled therapy in children should be reconsideredJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 2 2002JH Wildhaber Abstract: In current asthma guidelines, dosage regimens for inhalation therapy in children are based on adult doses and are generally titrated per kilogram of bodyweight or per square metre of body surface area. However, these recommendations do not correspond well with current knowledge of aerosol therapy in childhood. Lung deposition of the aerosolised drug is the key determinant for clinical efficacy and for systemic side effects of inhalation therapy. Lung deposition increases with age, whereas lung deposition expressed as a percentage per kilogram bodyweight is age-independent. This finding is explained by the self-regulating effect of age-dependent airway anatomy on lung deposition. Therefore, it is more likely that adult doses translate into paediatric doses only by virtue of the differences in self-limiting pulmonary deposition when using the same absolute nominal doses of the medication. Adapting the adult dose to a paediatric dose calculated on body size might be unnecessary and could lead to insufficient pulmonary deposition of medication. These findings suggest that dosage regimens for inhalation therapy for children may have to be reconsidered, and should be determined from dose-ranging studies rather than calculated from adult doses based on body size. [source] Fine-scale genetic structure and inferences on population biology in the threatened Mediterranean red coral, Corallium rubrumMOLECULAR ECOLOGY, Issue 19 2010J.-B. LEDOUX Abstract Identifying microevolutionary processes acting in populations of marine species with larval dispersal is a challenging but crucial task because of its conservation implications. In this context, recent improvements in the study of spatial genetic structure (SGS) are particularly promising because they allow accurate insights into the demographic and evolutionary processes at stake. Using an exhaustive sampling and a combination of image processing and population genetics, we highlighted significant SGS between colonies of Corallium rubrum over an area of half a square metre, which sheds light on a number of aspects of its population biology. Based on this SGS, we found the mean dispersal range within sites to be between 22.6 and 32.1 cm, suggesting that the surveyed area approximately corresponded to a breeding unit. We then conducted a kinship analysis, which revealed a complex half-sib family structure and allowed us to quantify the level of self-recruitment and to characterize aspects of the mating system of this species. Furthermore, significant temporal variations in allele frequencies were observed, suggesting low genetic drift. These results have important conservation implications for the red coral and further our understanding of the microevolutionary processes acting within populations of sessile marine species with a larval phase. [source] Brahms and the Principle of Destabilised BeginningsMUSIC ANALYSIS, Issue 1 2009Ryan Mcclelland ABSTRACT Despite the considerable research on moment-to-moment motivic development in Brahms's instrumental music, surprisingly few studies emphasise global thematic processes which involve transformations of initially destabilised thematic material. After placing Brahms's destabilised beginnings in the context of earlier nineteenth-century works, the article explores several pieces with destabilised beginnings in order to demonstrate Brahms's range of techniques for tonal and rhythmic-metric destabilisation, strategies used to maintain destabilisation at preliminary thematic returns and the relationships between destabilised beginnings and their eventual stabilised form. Tonal destabilisation subsumes several related and somewhat overlapping techniques, and the article pursues six which have particular relevance in Brahms's music: (1) stylistically marked chromaticism, (2) unusual dissonance treatment, (3) denial of harmonic or melodic cadence, (4) minimally stable diatonic harmonisation, (5) disjuncture between harmonic function and sonority type and (6) ambiguous establishment of key. The briefer consideration of rhythmic-metric destabilisation studies dissonance (1) at the level of metre and (2) at some level of hypermetre. The concluding section addresses stylistic and genre-specific constraints on destabilised beginnings as well as the implications of destabilised beginnings for the analysis of musical form, especially the distinction between rondo and modified sonata designs. [source] Overcoming growing water scarcity: Exploring potential improvements in water productivity in IndiaNATURAL RESOURCES FORUM, Issue 3 2010Upali A. Amarasinghe Abstract Improvements in water productivity (WP) are often suggested as one of the alternative strategies for overcoming growing water scarcity in India. This paper explores the potential improvements in WP of food grains at district level, which currently varies between 0.11 and 1.01 kilogram per cubic metre (kg/m3), in the 403 districts that account for 98% of the total production of food grains. The paper first finds the maximum yield function conditional on consumptive water use (CWU) and then explores the potential improvements in WP by: (a) bridging the gap between actual and maximum yield while keeping CWU constant; and (b) changing the maximum yield by adjusting the CWU using supplementary or deficit irrigation. Deficit irrigation in some areas may decrease yield but can increase production if land availability is not a constraint. A large potential exists for bridging the yield gap in irrigated areas with CWU between 300 and 475 mm. Of the 222 districts that fall under this category, a 50% reduction in yield gap alone could increase production by 100 million tonnes (Mt) without increasing CWU. Supplementary irrigation can increase yield and WP in rain-fed and irrigated areas of 266 and 16 districts with CWU is below 300 mm. Deficit irrigation in irrigated areas of 185 districts with CWU above 475 mm could increase yield, WP and production. Decreasing CWU in irrigated areas with CWU between 425 and 475 mm reduces yield slightly, but if availability of land is not a constraint then the benefits due to water saving and production increases could exceed the cost. [source] Wittgenstein on The Standard MetrePHILOSOPHICAL INVESTIGATIONS, Issue 2 2004W. J. Pollock In this paper I argue that Wittgenstein is correct when he says of the Standard Metre stick that we can neither say that it is or is not a metre in length , despite what our intuitions may tell us to the contrary. Specifically, the paper deals with Kripke's criticism of Wittgenstein's claim in Naming And Necessity and with Salmon's attempt to arbitrate between the two views. I conclude that, not only is Wittgenstein correct, but that both Kripke and Salmon (and possibly the majority of philosophers) simply do not understand the concept of measurement. [source] Field trial of serially passaged isolates of BYDV-PAV overcoming resistance derived from Thinopyrum intermedium in wheatPLANT BREEDING, Issue 3 2006F. Chain Abstract Barley yellow dwarf disease (BYDD) is one of the main viral diseases of small grain cereals. This disease, reported on numerous plant species of the Poaceae family, is caused by a complex of viral species including the species Barley yellow dwarf virus -PAV (BYDV-PAV, family Luteoviridae, genus Luteovirus), frequently found in western Europe. Resistance sources towards BYDD are scarce. Indeed, breeding-resistant genotypes is a long and expensive process. Thus, estimating the durability of the resistance genes before the achievement of selection would be an asset for breeders. One isolate of BYDV-PAV has been serially passaged on two hosts, ,Zhong ZH' and ,TC14', carrying a gene for partial resistance. The resulting viral population showed an increase of the speed of development of the infection in controlled conditions. In this study, these viral populations were evaluated in a 3-year field trial, including a susceptible host, ,Rendezvous', and a host carrying the resistance gene of ,TC14' in a ,Rendezvous' background, to assess the effect of serial passages in field conditions. Results indicate that isolates issued from serial passages on hosts carrying a gene for partial resistance induced increased damage in field conditions when compared with the initial isolate. Yield losses are mainly due to a decrease of the number of kernels per square metre. The interest on using partial resistance gene to control BYDD is discussed. [source] The Decomposition of some RDX and HMX Based Materials in the One Dimensional Time to Explosion Apparatus.PROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 1 2007Part 2. Abstract Various methods of assessment have been applied to the One Dimensional Time to Explosion (ODTX) apparatus and experiments with the aim of allowing an estimate of the comparative violence of the explosion event to be made. Non-mechanical methods used were a simple visual inspection, measuring the increase in the void volume of the anvils following an explosion and measuring the velocity of the sound produced by the explosion over 1 metre. Mechanical methods used included monitoring piezo-electric devices inserted in the frame of the machine and measuring the rotational velocity of a rotating bar placed on the top of the anvils after it had been displaced by the shock wave. This last method, which resembles original Hopkinson Bar experiments, seemed the easiest to apply and analyse, giving relative rankings of violence and the possibility of the calculation of a "detonation" pressure. [source] Willow (Salix spp.) and aspen (Populus tremula) regrowth after felling by the Eurasian beaver (Castor fiber): implications for riparian woodland conservation in ScotlandAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 1 2009Kevin Jones Abstract 1.A proposed trial reintroduction of the Eurasian beaver (Castor fiber L.) to Scotland has recently been approved (May 2008). A previous proposal was turned down by the licensing authority, partly over the perceived risks to woodland within a Special Area of Conservation. 2.This paper presents data on two years of willow (Salix spp.) and aspen (Populus tremula L.) regrowth following tree felling by captive beavers within two large semi-natural enclosures in eastern Scotland. Both willow and aspen are highly preferred by beavers. 3.Regrowth of willow stems was quantified from cut stumps, felled logs and partially severed (,incompletely felled') trees, and compared with growth of stems in the canopies of untouched willows. 4.Maximum annual regrowth was observed in incompletely felled trees, followed by cut stumps and then unfelled control trees. Mean regrowth rates were ca 18 m regrowth per metre of measured tree section per year in incompletely felled trees. This was approximately 12 times more annual regrowth than that observed in unfelled trees, despite apparently selective browsing of the regrowth of incompletely felled trees by roe deer. 5.Although incompletely felled willows represent a relatively small component of felling activity (9% of all felled willow), they contribute disproportionately to the biomass of beaver-engineered riparian woodlands, creating a more multi-layered habitat structure. 6.Willow regrowth in inundated areas was avoided by deer, and harvesting of regrowth by beavers was rare. 7.Significant regrowth from 11 stumps of aspen in 2 years post-felling occurred by suckering, with 85 suckers of mean height 2.1 m being recorded, all of which were subsequently avoided by browsing deer and beavers. 8.These data suggest that rapid regeneration of willow and aspen will occur in riparian woodlands in the event of major felling activity by Eurasian beaver, even in the presence of low to moderate levels of roe deer browsing, and that the conservation status of both these trees or the wider habitats that they form would not be threatened by a well planned and managed reintroduction of beavers to Scotland. Copyright © 2008 John Wiley & Sons, Ltd. [source] Reproductive potential and seedling establishment of the invasive alien tree Schinus molle (Anacardiaceae) in South AfricaAUSTRAL ECOLOGY, Issue 6 2009DONALD M. IPONGA Abstract Schinus molle (Peruvian pepper tree) was introduced to South Africa more than 150 years ago and was widely planted, mainly along roads. Only in the last two decades has the species become naturalized and invasive in some parts of its new range, notably in semi-arid savannas. Research is being undertaken to predict its potential for further invasion in South Africa. We studied production, dispersal and predation of seeds, seed banks, and seedling establishment in relation to land uses at three sites, namely ungrazed savanna once used as a military training ground; a savanna grazed by native game; and an ungrazed mine dump. We found that seed production and seed rain density of S. molle varied greatly between study sites, but was high at all sites (384 864,1 233 690 seeds per tree per year; 3877,9477 seeds per square metre per year). We found seeds dispersed to distances of up to 320 m from female trees, and most seeds were deposited within 50 m of putative source trees. Annual seed rain density below canopies of Acacia tortillis, the dominant native tree at all sites, was significantly lower in grazed savanna. The quality of seed rain was much reduced by endophagous predators. Seed survival in the soil was low, with no survival recorded beyond 1 year. Propagule pressure to drive the rate of recruitment: densities of seedlings and sapling densities were higher in ungrazed savanna and the ungrazed mine dump than in grazed savanna, as reflected by large numbers of young individuals, but adult : seedling ratios did not differ between savanna sites. Frequent and abundant seed production, together with effective dispersal of viable S. molle seed by birds to suitable establishment sites below trees of other species to overcome predation effects, facilitates invasion. Disturbance enhances invasion, probably by reducing competition from native plants. [source] Effects of the El Niño southern oscillation on Turbo torquatus (Gastropoda) and their kelp habitatAUSTRAL ECOLOGY, Issue 5 2008PIERS ETTINGER-EPSTEIN Abstract Turbo torquatus (hereafter Turbo) were abundant and patchily distributed, especially in algal dominated habitats in shallow water (less then 10 metres) on rocky reefs in central New South Wales, Australia. Although the assemblage of algae was similar in barrens with and without crevices, Turbo were most abundant in crevices, suggesting that shelter was important. Experimental removal of the kelp canopy resulted in a great decrease in the number of Turbo. This was despite cleared patches containing more filamentous food algae, further highlighting the importance of shelter. The density of Turbo in kelp forests ranged from six to seven per square metre in times of abundance and less then one per square metre at other times over a 12-year period. Variation in the resource base (i.e. food algae and kelp cover) was strongly linked to the abundance of Turbo. Abundance of Turbo was lowest when the density of adult kelp was low (less than 14 plants per square metre). The condition of kelp was severely affected during the 1997,1998 and 2002 El Niño events and was compromised 2,4 years after each event. These pulse events and related loss of shelter probably contributed to a decline in abundance of Turbo. This model was further supported when Turbo abundance increased with a subsequent increase in the density of kelp. [source] Ecological contrasts across an Antarctic land,sea interfaceAUSTRAL ECOLOGY, Issue 5 2006CATHERINE L. WALLER Abstract We report the composition of terrestrial, intertidal and shallow sublittoral faunal communities at sites around Rothera Research Station, Adelaide Island, Antarctic Peninsula. We examined primary hypotheses that the marine environment will have considerably higher species richness, biomass and abundance than the terrestrial, and that both will be greater than that found in the intertidal. We also compared ages and sizes of individuals of selected marine taxa between intertidal and subtidal zones to test the hypothesis that animals in a more stressed environment (intertidal) would be smaller and shorter lived. Species richness of intertidal and subtidal communities was found to be similar, with considerable overlap in composition. However, terrestrial communities showed no overlap with the intertidal, differing from previous reports, particularly from further north on the Antarctic Peninsula and Scotia Arc. Faunal biomass was variable but highest in the sublittoral. While terrestrial communities were depauperate with low biomass they displayed the highest overall abundance, with a mean of over 3 × 105 individuals per square metre. No significant differences in ages of intertidal and subtidal individuals of the same species were found, with bryozoan colonies of up to 4 years of age being present in the intertidal. In contrast with expectation and the limited existing literature we conclude that, while the Antarctic intertidal zone is clearly a suboptimal and highly stressful habitat, its faunal community can be well established and relatively diverse, and is not limited to short-term opportunists or waifs and strays. [source] Grapevine dormant pruning weight prediction using remotely sensed dataAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2003S.Z. DOBROWSKI Abstract Aerial image analysis was utilised to predict dormant pruning weights between two growing seasons. We utilised an existing in-row spacing trial in order to examine the relationship between dormant pruning weights and remotely sensed data. The experimental vineyard had a constant between-row spacing (2.44 m) and five different in-row spacings (0.91, 1.52, 2.13, 2.74 and 3.35 m) resulting in spatial variation in canopy volume and dormant pruning weights (kg/metre of row). It was shown that the ratio vegetation index (NIR/R) was linearly correlated with field-wide measurements of pruning weight density (dormant pruning weight per metre of canopy) for both the 1998 and 1999 growing seasons (r2= 0.68 and 0.88, respectively). Additionally, it was shown that the regression parameters remained consistent between the two growing seasons allowing for an inter-annual comparison such that the vegetation index vs canopy parameter relationship determined for the 1998 growing season was used to predict field-wide pruning weight densities in the 1999 growing season prior to harvest. [source] Distribution of myrmecochorous species over the landscape and their potential long-distance dispersal by emus and kangaroosDIVERSITY AND DISTRIBUTIONS, Issue 1 2008María Calviño-Cancela ABSTRACT Topographical heterogeneity can create a mosaic of substrate types leading to the formation of isolated plant populations. Seed dispersal then becomes crucial for the colonization of such suitable but remote substrate types. We surveyed the distribution of seven elaiosome-bearing species (myrmecochores) over 5 km2 of natural heathland in southwestern Australia. Ants are the standard means of dispersal of these species, which provide limited dispersal (usually of a few metres). Six species were associated with particular substrate types (dune or swale) and all occurred as discrete populations, on average 270,500 m apart, with closest dune edges 280 m apart. We evaluated the possible roles of emus and kangaroos as alternative agents of long-distance seed dispersal between substrate types. Their droppings contained viable seeds of three of the target species, as well as other myrmecochores, and were evenly distributed over the substrate types. While migration of these plant species between preferred substrate types seems unlikely when considering only their standard dispersal agents (ants), it is highly likely in the presence of emus (in particular) and kangaroos that act as non-standard dispersers. This may have important consequences for plant species conservation by increasing habitat connectivity and favouring regional persistence. [source] Regional differences in kelp-associated algal assemblages on temperate limestone reefs in south-western AustraliaDIVERSITY AND DISTRIBUTIONS, Issue 6 2003Thomas Wernberg Abstract.,Ecklonia radiata (C. Agardh) J. Agardh kelp beds , a characteristic feature of the nearshore environment along the south-west Australian coastline , contribute significantly to the coastal biodiversity in temperate Australia, yet, little is known about the organization of these macroalgal assemblages. By compiling existing and new data sets from habitat surveys, we have characterized and compared the structure of kelp-associated macroalgal assemblages in three regions (Marmion Lagoon, Hamelin Bay and the marine environment neighbouring the Fitzgerald River National Park) across more than 1000 kilometres of the south-west Australian coastline. 152 macroalgal taxa had been recognized within the three regions and this is in the range of species richness reported from other Australian and African kelp beds. The kelp-associated algal assemblages were regionally distinct, 66% of all taxa were only found in one region and only 17 taxa were found in all three regions. Adjacent regions shared an additional 13,15 taxa. The regional shifts in assemblage structure were evident in species composition of both canopy and understorey. The organization of assemblages followed a spatial hierarchy where differences in assemblage structure were larger among regions (hundreds of kilometres apart) than among sites within regions (kilometres apart) and differences among sites within region were larger than differences among quadrats within sites (metres apart). Despite this hierarchy each level of nesting contributed approximately the same to total variation in assemblage structure and these spatial patterns were stronger than temporal differences from seasons to 2,3 years. Our results suggest that local and small-scale processes contribute considerably to heterogeneity in macroalgal assemblages throughout south-western Australia, and, in particular, our results are consistent with E. radiata exerting a strong influence on macroalgal assemblage structure. Further, our study contradicts the existence of a general south-west Australian kelp assemblage, although a few species may form the core of E. radiata associations across regions. [source] The use of short-lived radionuclides to quantify transitional bed material transport in a regulated riverEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2007Nira L. Salant Abstract We investigate the use of the short-lived fallout radionuclide beryllium-7 (7Be; t1/2 = 53·4 days) as a tracer of medium and coarse sand (0·25,2 mm), which transitions between transport in suspension and as bed load, and evaluate the effects of impoundment on seasonal and spatial variations in bed sedimentation. We measure 7Be activities in approximately monthly samples from point bar and streambed sediments in one unregulated and one regulated stream. In the regulated stream our sampling spanned an array of flow and management conditions during the annual transition from flood control in the winter and early spring to run-of-the-river operation from late spring to autumn. Sediment stored behind the dam during the winter quickly became depleted in 7Be activity. This resulted in a pulse of ,dead' sediment released when the dam gates were opened in the spring which could be tracked as it moved downstream. Measured average sediment transport velocities (30,80 metres per day (m d,1)) exceed those typically reported for bulk bed load transport and are remarkably constant across varied flow regimes, possibly due to corresponding changes in bed sand fraction. Results also show that the length scale of the downstream impact of dam management on sediment transport is short (c. 1 km); beyond this distance the sediment trapped by the dam is replaced by new sediment from tributaries and other downstream sources. 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