Home About us Contact
|
Home About us Contact | ||
|
|
||
Seasonal Differences (seasonal + difference)
Kinds of Seasonal Differences Selected AbstractsSeasonal differences in the adaptability of herbage species to environmental variations in a long-term grazing experimentGRASSLAND SCIENCE, Issue 1 2007Yiruhan Abstract Mixtures of orchardgrass, perennial ryegrass, tall fescue, redtop, Kentucky bluegrass, and white clover were sown in autumn 1973. Two 8-year grazing experiments were conducted at the National Grassland Research Institute (Nasushiobara, Japan) to determine the effects of grazing intensity and nitrogen levels on pasture ecosystems. These experiments involved two different grazing intensities (1974,1981) and two different nitrogen levels (1982,1989). Large spatiotemporal variations in phytomass due to environmental variations were observed in both experiments. Finlay,Wilkinson analysis was applied to clarify seasonal (monthly) differences in the adaptability of the herbage species, as measured by phytomass, to environmental variations by year and treatments in the two experiments. Seasonality in the adaptability to environments differed greatly among species. In this paper, we examined from livestock farmers' standpoint whether seasonality in adaptability of herbage species in the grazing pasture could be satisfied. A significantly high adaptability was shown for: orchardgrass from May to July and November; tall fescue in April, June and July, and November; redtop and Kentucky bluegrass in April; and Zoysia japonica in September and October. In contrast, perennial ryegrass and white clover exhibited very low adaptability in any season. Z. japonica and weeds such as Pennisetum alopecuroides, Eragrostis ferruginea and Digitaria adscendens, which had invaded from surrounding areas, showed low adaptability, except in autumn, when they showed moderate adaptability. [source] Seasonal differences in spatial distribution of small carnivores in fragmented savannah landscapesAFRICAN JOURNAL OF ECOLOGY, Issue 4 2008Niels Blaum First page of article [source] Variability in the carbon isotope signature of Prochilodus lineatus (Prochilodontidae, Characiformes) a bottom-feeding fish of the Neotropical regionJOURNAL OF FISH BIOLOGY, Issue 6 2007C. A. Lopes The spatial and seasonal variability of stable carbon isotopes in detritivorous Prochilodus lineatus, primary producers and particulate organic carbon (POC) were examined to promote a better understanding of the trophic dynamics of food webs in Neotropical ecosystems. Spatial variability in carbon isotope composition in the species showed a decreasing gradient in the Upper Paraná River system, from the Paraná River and Itaipu Reservoir subsystems to the Baía and Ivinheima subsystems. Fish ,13C followed the isotopic trend of POC along the Paraná River and Baía subsystem. Seasonal differences were not observed in fish. The analysis of percentile contribution of C3 and C4 sources in the species diet revealed the predominance of C3 plants (phytoplanktonic and periphytic algae and riparian vegetation) in most of the analysed subsystems and seasons. Nevertheless, the considerable participation of riparian vegetation was verified, especially in the Ivinheima subsystem in the dry season. C4 macrophytes presented a maximum contribution along the Upper Paraná River. These results demonstrate the existence of specific variability for the consumer and their food sources in different environments of the same ecosystem. [source] Macrofauna Communities in the Eastern Mediterranean Deep SeaMARINE ECOLOGY, Issue 3 2003Ingrid Kröncke Abstract., During two expeditions with RV ,Meteor' in summer 1993 and winter 1997/98 the structural and functional diversity of the benthic system of the highly oligotrophic eastern Mediterranean deep sea was investigated. The macrofauna communities were dominated by polychaetes even at the deepest stations. The fauna at shallow stations was dominated by surface deposit feeders, whereas subsurface deposit feeders and predators generally increased with depth. A high percentage of suspension-feeding Porifera was found in the Levantine Basin. Mean abundance and number of taxa of both expeditions were significantly correlated to depth and distance to the nearest coast as well as to the total organic carbon (TOC) content in sediments. Numbers of taxa and abundance decreased generally with depth, although lowest numbers were not found at the deepest stations but in the extremely oligotrophic Levantine and Ierapetra Basin. Biomass measured during the second cruise was extremely low in the Ierapetra Basin and comparable to other extreme oligotrophic seas. The significant correlations found for TOC contents and macrofauna with distance to coast during both expeditions apparently reflect the role of hydrographically governed transport of organic matter produced in coastal regions into greater and extreme depths of the Mediterranean Sea. Seasonal differences in macrofauna communities due to seasonal differences in food supply were not found. However, recent large-scale hydrographic changes (Eastern Mediterranean Transient, EMT) might change the oligotrophy and, thus, the structure of the benthic communities in the Eastern Mediterranean deep sea. [source] Seasonal differences in population-, ensemble- and community-level responses of bats to landscape structure in AmazoniaOIKOS, Issue 10 2010Brian T. Klingbeil The amount (composition) and spatial arrangement (configuration) of forest patches in fragmented landscapes influence the accessibility, as well as the abundance and diversity of resources available to bats. Moreover, tropical fruit and insect abundance differ seasonally in response to changes in precipitation, and many bats in the family Phyllostomidae employ seasonal reproductive strategies. Because reproductive activities involve constraints on time and energy as well as increased nutritional demands, foraging behavior and home range size may differ between wet and dry seasons. Nonetheless, seasonal variation in response to landscape structure by bats has not been examined previously. Consequently, population-, ensemble- and assemblage-level responses of phyllostomids to landscape composition and configuration were quantified separately during the wet and dry season at three circular focal scales (1, 3 and 5 km radii) for 14 sites in fragmented lowland Amazon forest. Responses to landscape characteristics were scale-dependent, species-specific, and seasonal. Abundances of frugivores responded to landscape composition in the dry season and to landscape configuration in the wet season. Conversely, abundances of animalivores responded to landscape configuration in the dry season and to landscape composition in the wet season. Divergent responses to landscape structure between seasons suggest that variation in resource abundance and diversity play a significant role in structuring population-, ensemble- and assemblage-level patterns. As such, considerations of the effects of dietary flexibility and reproductive constraints on foraging strategies and habitat use may be important when designing management plans that successfully promote long-term persistence of biodiversity in fragmented landscapes. [source] Photosynthesis and Photoprotection in Overwintering PlantsPLANT BIOLOGY, Issue 5 2002W. W. Adams III Abstract: Seasonal differences in the capacity of photosynthetic electron transport, leaf pigment composition, xanthophyll cycle characteristics and chlorophyll fluorescence emission were investigated in two biennial mesophytes (Malva neglecta and Verbascum thapsus) that grow in full sunlight, and in leaves/needles of sun and shade populations of several broad-leafed evergreens and conifers (Vinca minor, Euonymus kiautschovicus, Mahonia repens, Pseudotsuga menziesii [Douglas fir], and Pinus ponderosa). Both mesophytic species maintained or upregulated photosynthetic capacity in the winter and exhibited no upregulation of photoprotection. In contrast, photosynthetic capacity was downregulated in sun leaves/needles of V. minor, Douglas fir, and Ponderosa pine, and even in shade needles of Douglas fir. Interestingly, photosynthetic capacity was upregulated during the winter in shade leaves/needles of V. minor, Ponderosa pine and Euonymus kiautschovicus. Nocturnal retention of zeaxanthin and antheraxanthin, and their sustained engagement in a state primed for energy dissipation, were observed largely in the leaves/needles of sun-exposed evergreen species during winter. Factors that may contribute to these differing responses to winter stress, including chloroplast redox state, the relative levels of source and sink activity at the whole plant level, and apoplastic versus symplastic phloem loading, are discussed. [source] Seasonal differences in photosynthesis between the C3 and C4 subspecies of Alloteropsis semialata are offset by frost and droughtPLANT CELL & ENVIRONMENT, Issue 7 2008DOUGLAS G. IBRAHIM ABSTRACT The regional abundance of C4 grasses is strongly controlled by temperature, however, the role of precipitation is less clear. Progress in elucidating the direct effects of photosynthetic pathway on these climate relationships is hindered by the significant genetic divergence between major C3 and C4 grass lineages. We addressed this problem by examining seasonal climate responses of photosynthesis in Alloteropsis semialata, a unique grass species with both C3 and C4 subspecies. Experimental manipulation of rainfall in a common garden in South Africa tested the hypotheses that: (1) photosynthesis is greater in the C4 than C3 subspecies under high summer temperatures, but this pattern is reversed at low winter temperatures; and (2) the photosynthetic advantage of C4 plants is enhanced during drought events. Measurements of leaf gas exchange over 2 years showed a significant photosynthetic advantage for the C4 subspecies under irrigated conditions from spring through autumn. However, the C4 leaves were killed by winter frost, while photosynthesis continued in the C3 plants. Unexpectedly, the C4 subspecies also lost its photosynthetic advantage during natural drought events, despite greater water-use efficiency under irrigated conditions. This study highlights previously unrecognized roles for climatic extremes in determining the ecological success of C3 and C4 grasses. [source] Do endogenous seasonal cycles of food intake influence foraging behaviour and intake by grazing sheep?FUNCTIONAL ECOLOGY, Issue 5 2000G. R. Iason Abstract 1.,Large herbivores living in temperate regions show different degrees of seasonal biological variation, including voluntary food intake (VFI). The decline of VFI in winter has been hypothesized to be an evolved response to lower food availability or quality, which can act as an internal constraint on food intake. 2.,The hypotheses were tested that (i) animals that have a greater inherent seasonal variation of VFI, measured indoors under ad libitum conditions, would also have a greater seasonal variation in intake and grazing behaviour under field conditions, and (ii) greater seasonal variation in intake and grazing behaviour under field conditions would be expressed at a higher level of food availability. 3.,The intake and grazing behaviour in summer and winter, of three breeds of sheep, were compared at two levels of food availability (at pasture heights of 3·7 and 5·4 cm). The breeds were known to have contrasting degrees of seasonal variation in food intake when fed ad libitum; the VFI of the Shetland (SH) and Scottish Blackface (BF) sheep varies greatly between seasons whereas that of the Dorset Horn (DH) is less seasonally variable. 4.,All three breeds consistently increased their rates of biting and duration of grazing activity in the winter, taking many more smaller bites each day than in the summer, and both digestibility and intake were lower in winter than in summer. 5.,Contrary to expectation, the DH ewes had the highest seasonal difference of dry matter intake at pasture, whereas the SH breed had the lowest variation of intake between seasons. 6.,This experiment provides no evidence that differences between seasons in intake and foraging behaviour in the field vary with the animals' degree of endogenous seasonal variation in VFI. Variation between seasons was consistent at both levels of resource availability, suggesting that it resulted from seasonal changes in food quality (digestibility) rather than biomass availability. It is not easy to extrapolate from laboratory feeding studies, where animals' own physiological constraints apply, to foraging ecology in the field, where constraints imposed by the environment may be more important. [source] Seasonal changes of antioxidant and oxidative parameters in the coral Pocillopora capitata on the Pacific coast of MexicoMARINE ECOLOGY, Issue 3 2010Marco A. Liñán-Cabello Abstract The physiological responses of the coral Pocillopora capitata to environmental conditions common in winter and summer were studied in 2007 during February,March (winter) and June,July (summer) at La Boquita reef (Manzanillo, Colima, Mexico). Shallow and deep sampling stations were established at different distances from a small jetty built next to the Juluapan Lagoon. We analyzed superoxide radicals () and lipid peroxidants (TBARS); the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione-S-transferase (GST); chlorophyll a (Chl a), zooxanthellae density (ZD); and mycosporine-like amino acids (MAAs). Our results showed that the , TBARS, CAT, GST, MAAs, and Chl a, levels were significantly higher in summer (P < 0.05); no seasonal difference was found for GPx, GR or ZD. We found significant differences (P < 0.05) in winter only for Chl a and ZD at shallow sites and, in contrast, for at deeper sites. The results of this study indicate that increasing temperature and radiation associated with seasonal changes (from winter to summer), the efficiency of the enzymes GST, CR and GPX, and the production of MAAs together form a powerful mechanism for P. capitata to offset the detrimental effects of environmental change. [source] Orbit characteristics of the tristatic EISCAT UHF meteorsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2008C. Szasz ABSTRACT The tristatic EISCAT 930-MHz UHF system is used to determine the absolute geocentric velocities of meteors detected with all three receivers simultaneously at 96 km, the height of the common radar volume. The data used in this study were taken between 2002 and 2005, during four 24-h runs at summer/winter solstice and vernal/autumnal equinox to observe the largest seasonal difference. The observed velocities of 410 tristatic meteors are integrated back through the Earth atmosphere to find their atmospheric entry velocities using an ablation model. Orbit calculations are performed by taking zenith attraction, Earth rotation as well as obliquity of the ecliptic into account. The results are presented in the form of different orbital characteristics. None of the observed meteors appears to be of extrasolar or asteroidal origin; comets, particularly short-period (<200 yr) ones, may be the dominant source for the particles observed. About 40 per cent of the radiants can be associated with the north apex sporadic meteor source and 58 per cent of the orbits are retrograde. There is evidence of resonance gaps at semimajor axis values corresponding to commensurabilities with Jupiter, which may be the first convincing evidence of Jupiter's gravitational influence on the population of small sporadic meteoroids surveyed by radar. The geocentric velocity distribution is bimodal with a prograde population centred around 38 km s,1 and a retrograde population peaking at 59 km s,1. The EISCAT radar system is located close to the Arctic Circle, which means that the North Ecliptic Pole (NEP) is near zenith once every 24 h, i.e. during each observational period. In this particular geometry, the local horizon coincides with the ecliptic plane. The meteoroid influx should therefore be directly comparable throughout the year. [source] Exudativory in the Bengal slow loris (Nycticebus bengalensis) in Trishna Wildlife Sanctuary, Tripura, northeast IndiaAMERICAN JOURNAL OF PRIMATOLOGY, Issue 2 2010N. Swapna Abstract In this study we estimated the extent of exudativory in Nycticebus bengalensis and examined whether exudates can be considered as fallback foods. This study was carried out in Trishna Wildlife Sanctuary, northeastern India, in winter (December,February) and summer (March and April). We estimated time,activity budget using instantaneous sampling and used continuous focal animal sampling to record all instances and durations of feeding, over a total of 177,hr. Feeding accounted for 22.3±2.2% of the activity budget, with no seasonal difference. Bengal slow lorises fed on exudates, nectar, fruit, bark, invertebrates and avian eggs. In addition to scraping they also obtained exudates by gouging holes into the bark of trees. In winter, lorises almost exclusively fed on exudates (94.3% of winter feeding time). In summer, exudates (67.3%) and nectar from one species (22.3%) dominated the diet. This study identifies the Bengal slow loris as the most exudativorous loris. Exudates rather than being a staple fallback food, seem to be a preferred, patchily distributed and common food in the diet of the Bengal slow loris. Exudativory in this species is characterized by high selectivity among species and seasonal variation, which may be related to variations in productivity of exudates and their chemical composition. An understanding of these factors is necessary for predicting the response of this species to human disturbance such as logging. This study also underscores the importance of protecting some of the common species such as Terminalia belerica on which the loris feeds during periods of scarcity. Am. J. Primatol. 72:113,121, 2010. © 2009 Wiley-Liss, Inc. [source] Greater hippocampal neuronal recruitment in food-storing than in non-food-storing birdsDEVELOPMENTAL NEUROBIOLOGY, Issue 4 2007Jennifer S. Hoshooley Abstract Previous research has shown heightened recruitment of new neurons to the chickadee hippocampus in the fall. The present study was conducted to determine whether heightened fall recruitment is associated with the seasonal onset of food-storing by comparing neurogenesis in chickadees and a non-food-storing species, the house sparrow. Chickadees and house sparrows were captured in the wild in fall and spring and received multiple injections of the cell birth marker bromodeoxyuridine (BrdU). Birds were held in captivity and the level of hippocampal neuron recruitment was assessed after 6 weeks. Chickadees showed significantly more hippocampal neuronal recruitment than house sparrows. We found no seasonal differences in hippocampal neuronal recruitment in either species. In chickadees and in house sparrows, one-third of new cells labeled for BrdU also expressed the mature neuronal protein, NeuN. In a region adjacent to the hippocampus, the hyperpallium apicale, we observed no significant differences in neuronal recruitment between species or between seasons. Hippocampal volume and total neuron number both were greater in spring than in fall in chickadees, but no seasonal differences were observed in house sparrows. Enhanced neuronal recruitment in the hippocampus of food-storing chickadees suggests a degree of neurogenic specialization that may be associated with the spatial memory requirements of food-storing behavior. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007. [source] Seasonal changes in frequency tuning and temporal processing in single neurons in the frog auditory midbrainDEVELOPMENTAL NEUROBIOLOGY, Issue 1 2005Jozien BM Goense Abstract Frogs rely on acoustic signaling to detect, discriminate, and localize mates. In the temperate zone, reproduction occurs in the spring, when frogs emerge from hibernation and engage in acoustically guided behaviors. In response to the species mating call, males typically show evoked vocal responses or other territorial behaviors, and females show phonotactic responses. Because of their strong seasonal behavior, it is possible that the frog auditory system also displays seasonal variation, as evidenced in their vocal control system. This hypothesis was tested in male Northern leopard frogs by evaluating the response characteristics of single neurons in the torus semicircularis (TS; a homolog of the inferior colliculus) to a synthetic mating call at different times of the year. We found that TS neurons displayed a seasonal change in frequency tuning and temporal properties. Frequency tuning shifted from a predominance of TS units sensitive to intermediate frequencies (700,1200 Hz) in the winter, to low frequencies (100,600 Hz) in the summer. In winter and early spring, most TS neurons showed poor, or weak, time locking to the envelope of the amplitude-modulated synthetic call, whereas in late spring and early summer the majority of TS neurons showed robust time-locked responses. These seasonal differences indicate that neural coding by auditory midbrain neurons in the Northern leopard frog is subject to seasonal fluctuation. © 2005 Wiley Periodicals, Inc. J. Neurobiol, 2005 [source] Differences in temperature, organic carbon and oxygen consumption among lowland streamsFRESHWATER BIOLOGY, Issue 12 2005KAJ SAND-JENSEN Summary 1. Temperature, organic carbon and oxygen consumption were measured over a year at 13 sites in four lowlands streams within the same region in North Zealand, Denmark with the objectives of determining: (i) spatial and seasonal differences between open streams, forest streams and streams with or without lakes, (ii) factors influencing the temperature dependence of oxygen consumption rate, (iii) consequences of higher temperature and organic content in lake outlets on oxygen consumption rate, and (iv) possible consequences of forecasted global warming on degradation of organic matter. 2. High concentrations of easily degradable dissolved (DOC) and particulate organic carbon (POC) were found in open streams downstream of plankton-rich lakes, while high concentrations of recalcitrant DOC were found in a forest brook draining a forest swamp. Concentrations of predominantly recalcitrant POC and DOC were low in a groundwater-fed forest spring. Overall, DOC concentration was two to 18 times higher than POC concentrations. 3. Oxygen consumption rate at 20 °C was higher during summer than winter, higher in open than shaded streams and higher in lake outlets than inlets. Rate was closely related to concentrations of chlorophyll and POC but not to DOC. The ratio of oxygen consumption rate to total organic concentrations (DOC + POC), serving as a measure of organic degradability, was highest downstream of lakes, intermediate in open streams and lowest in forest streams. 4. Temperature coefficients describing the exponential increase of oxygen consumption rate between 4 and 20 °C averaged 0.121 °C,1 (Q10 of 3.35) in 70 measurements and showed no significant variations between seasons and stream sites or correlations with ambient temperature and organic content. 5. Oxygen consumption rate was enhanced downstream of lakes during summer because of higher temperature and, more significantly, greater concentrations of degradable organic carbon. Oxygen consumption rates were up to seven times higher in the stream with three impoundments than in a neighbouring unshaded stream and 21 times higher than in the groundwater-fed forest spring. 6. A regional climate model has calculated a dramatic 4,5 °C rise in air temperature over Denmark by 2070,2100. If this is realised, unshaded streams are estimated to become 2,3 °C warmer in summer and winter and 5,7 °C warmer in spring and, thereby, increase oxygen consumption rates at ambient temperature by 30,40% and 80,130%, respectively. Faster consumption of organic matter and dissolved oxygen downstream of point sources should increase the likelihood of oxygen stress of the stream biota and lead to the export of less organic matter but more mineralised nutrients to the coastal waters. [source] RUNOFF PRODUCTION AND EROSION PROCESSES ON A DEHESA IN WESTERN SPAIN,GEOGRAPHICAL REVIEW, Issue 3 2002ANTONIO CEBALLOS ABSTRACT. Runoff generation and soil erosion were investigated at the Guadalperalón experimental watershed (western Spain), within the land-use system known as dehesa, or open, managed evergreen forests. Season and type of surface were found to control runoff and soil-loss rates. Five soil units were selected as representative of surface types found in the study area: hillslope grass, bottom grass, tree cover, sheep trails, and shrub cover. Measurements were made in various conditions with simulated rainfall to gain an idea of the annual variation in runoff and soil loss. Important seasonal differences were noted due to surface cover and moisture content of soil, but erosion rates were determined primarily by runoff. Surfaces covered with grass and shrubs always showed less erosion; surfaces covered with holm oaks showed higher runoff rates, due to the hydrophobic character of the soils. Concentrations of runoff sediment during the simulations confirmed that erosion rates at the study site depended directly on the sediment available on the soil surface. [source] Effects of Land Use on Ground Water Quality in the Anoka Sand Plain Aquifer of MinnesotaGROUND WATER, Issue 4 2003Michael D. Trojan We began a study, in 1996, to compare ground water quality under irrigated and nonirrigated agriculture, sewered and nonsewered residential developments, industrial, and nondeveloped land uses. Twenty-three monitoring wells were completed in the upper meter of an unconfined sand aquifer. Between 1997 and 2000, sampling occurred quarterly for major ions, trace inorganic chemicals, volatile organic compounds (VOCs), herbicides, and herbicide degradates. On single occasions, we collected samples for polynuclear aromatic hydrocarbons (PAHs), perchlorate, and coliform bacteria. We observed significant differences in water chemistry beneath different land uses. Concentrations of several trace inorganic chemicals were greatest under sewered urban areas. VOC detection frequencies were 100% in commercial areas, 52% in sewered residential areas, and <10% for other land uses. Median nitrate concentrations were greatest under irrigated agriculture (15,350 ,g/L) and nonsewered residential areas (6080 ,g/L). Herbicides and degradates of acetanilide and triazine herbicides were detected in 86% of samples from irrigated agricultural areas, 68% of samples from nonirrigated areas, and <10% of samples from other land uses. Degradates accounted for 96% of the reported herbicide mass. We did not observe seasonal differences in water chemistry, but observed trends in water chemistry when land use changes occurred. Our results show land use is the dominant factor affecting shallow ground water quality. Trend monitoring programs should focus on areas where land use is changing, while resource managers and planners must consider potential impacts of land use changes on ground water quality. [source] Survival analysis of Little Penguin Eudyptula minor chicks on Motuara Island, New ZealandIBIS, Issue 4 2001MARTIN RENNER Chick survival of Little Penguins Eudyptula minor was studied on predator-free Motuara Island, Cook Strait, New Zealand (41d,05'S, 174d,15'E), in 1995 and 1996. We used the Kaplan-Meier estimator and robust Cox regression to estimate chick survival rate (pL se) at 0.325 pL 0.044, leading to an estimated survival from laying to fledging of 0.13 or a reproductive output of 0.26 chicks per pair and breeding attempt. Starvation posed the greatest mortality risk, followed by unknown factors and rain. Risk of death due to rain was restricted to the guard stage, whereas starvation occurred throughout the nesting period, though with a peak in the early guard stage. Significant seasonal differences in survival rate were detected in both years, but with reversed trends, survival decreasing with the season in 1995 and increasing in 1996. Failure of adults to relieve their partner on the nest after chicks hatched accounted for 16% mortality or 34% of all chick deaths. Differences in chick survival rate between nest types were significant in 1995, a year with high rainfall, but not in 1996. Nests in the base of hollow trees had the highest chick survival rate. Of chicks in open nests - a nest type that is unusual for this species - 5.4% fledged. Our results suggest that on Motuara Island good breeding sites are scarce and that the food supply has been poor during the years of this study. [source] HISTALP,historical instrumental climatological surface time series of the Greater Alpine RegionINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 1 2007Ingeborg Auer This paper describes the HISTALP database, consisting of monthly homogenised records of temperature, pressure, precipitation, sunshine and cloudiness for the ,Greater Alpine Region' (GAR, 4,19°E, 43,49°N, 0,3500m asl). The longest temperature and air pressure series extend back to 1760, precipitation to 1800, cloudiness to the 1840s and sunshine to the 1880s. A systematic QC procedure has been applied to the series and a high number of inhomogeneities (more than 2500) and outliers (more than 5000) have been detected and removed. The 557 HISTALP series are kept in different data modes: original and homogenised, gap-filled and outlier corrected station mode series, grid-1 series (anomaly fields at 1° × 1°, lat × long) and Coarse Resolution Subregional (CRS) mean series according to an EOF-based regionalisation. The leading climate variability features within the GAR are discussed through selected examples and a concluding linear trend analysis for 100, 50 and 25-year subperiods for the four horizontal and two altitudinal CRSs. Among the key findings of the trend analysis is the parallel centennial decrease/increase of both temperature and air pressure in the 19th/20th century. The 20th century increase (+1.2 °C/+ 1.1 hPa for annual GAR-means) evolved stepwise with a first peak near 1950 and the second increase (1.3 °C/0.6hPa per 25 years) starting in the 1970s. Centennial and decadal scale temperature trends were identical for all subregions. Air pressure, sunshine and cloudiness show significant differences between low versus high elevations. A long-term increase of the high-elevation series relative to the low-elevation series is given for sunshine and air pressure. Of special interest is the exceptional high correlation near 0.9 between the series on mean temperature and air pressure difference (high-minus low-elevation). This, further developed via some atmospheric statics and thermodynamics, allows the creation of ,barometric temperature series' without use of the measures of temperature. They support the measured temperature trends in the region. Precipitation shows the most significant regional and seasonal differences with, e.g., remarkable opposite 20th century evolution for NW (9% increase) versus SE (9% decrease). Other long- and short-term features are discussed and indicate the promising potential of the new database for further analyses and applications. Copyright © 2006 Royal Meteorological Society. [source] Air temperatures at Armagh Observatory, Northern Ireland, from 1796 to 2002INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 8 2005C. J. Butler Abstract Three independent mean temperature series for Armagh Observatory, covering the period 1796,2002 have been calibrated and corrected for the time of reading and exposure. Agreement between the three series is good in regions of overlap. With a short gap in the Armagh data from 1825 to 1833 filled by data from two stations in Dublin, the resulting series is the longest for the island of Ireland and one of the longest for any single site in the British Isles. Over the past 207 years, we note that temperatures in Armagh, in all seasons, show a gradual overall trend upwards. However, there are seasonal differences: summer and spring temperatures have increased by only half as much as those in autumn and winter. This is partly due to the exceptionally cold winters and autumns experienced prior to 1820. Relative to the overall trend, warm periods occurred in Ireland, as in other parts of Europe, in the mid-19th century, in the mid-20th century and at the end of the 20th century. Relatively cool temperatures prevailed in the early 19th century, in the 1880s and in the 1970s. Thus, if the baseline against which current temperatures are compared were moved from the late 19th century to include the earlier warm period, the apparent warming at the end of the late 20th century would be correspondingly reduced. A gradual decline in the daily temperature range at Armagh since 1844 may have resulted from higher minimum temperatures associated with increased cloudiness. A 7.8 year periodicity is identified in winter and spring mean temperatures at Armagh, which is probably a consequence of the North Atlantic oscillation. Copyright © 2005 Royal Meteorological Society [source] Go climb a mountain: an application of recreation demand modelling to rock climbing in ScotlandJOURNAL OF AGRICULTURAL ECONOMICS, Issue 1 2001Nick Hanley In this paper, we apply random utility modelling techniques to rock-climbing in Scotland. Attributes relevant to choices over rock-climbing sites were identified from focus groups with climbers, along with a categorisation of principal climbing areas. A survey of climbers yielded 267 responses, which were then used as the basis for modelling. We compare a standard multi-nominal logit model with a random parameters approach, and look at seasonal differences in behaviour, and at the implications of different treatments of travel time. The random utility models showed that most of the attributes selected were significant determinants of choice. Welfare estimates of changes in site attributes are presented, which are relevant to policy choices currently facing land managers. [source] Diet composition of Belone belone (Linnaeus, 1761) (Pisces: Belonidae) in the Aegean SeaJOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2009T. M. Sever Summary The objective of this study was to determine the monthly dietary pattern in migratory garfish and to improve our understanding in the seasonality of prey choice. Gut contents of 597 Belone belone specimens collected from the eastern Aegean Sea (Turkey) were analyzed: 79.2% contained food in their guts and 20.8% had empty guts. Crustaceans (36.7%) were the most important prey with a 36.7 index of relative importance (%IRI). Especially brachyurans (13.0%) and copepods played a major role (10.1%), followed by teleosts (26.1%) and other food categories (23.3%) (much of which was of terrestrial origin, including insects). Nannocalanus minor, Clausocalanus arcuicornis, Temora stylifera, Labidocera wollastoni and Oncea media were important copepods found in the guts of B. belone specimens. Analysis of variance of the monthly weight data indicated no significant seasonal differences, except for January and February. [source] The persistence of bifidobacteria populations in a river measured by molecular and culture techniquesJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2009X. Bonjoch Abstract Aims:, To determine relative to faecal coliforms (FC) and sulfite-reducing clostridia (SRC), the environmental persistence of natural populations of Bifidobacterium spp. enumerated by culturing and quantitative polymerase chain reaction (q-PCR). Methods and Results:, Dialysis tubing containing river supplemented with overnight cultures of Bifidobacterium adolescentis (BA) and Bifidobacterium dentium (BD) or urban wastewater were suspended in a river for up to 10 days. At intervals, the contents of each dialysis tube were assayed using q-PCR assays for BA and BD, and selective culture media for FC, SRC, total bifidobacteria (TB), sorbitol-fermenting bifidobacteria (SFB) and cultivable BA. Mean summer T90 values were 251 h for SRC, 92 h for FC, 48 h for BA and BD by q-PCR, and 9 h for TB. Conclusions:,Bifidobacterium spp. was the population with the lowest persistence, showing seasonal differences in T90 when measured by culture techniques or by q-PCR. This difference in relative persistence is because of a longer persistence of molecular targets than cultivable cells. Significance and Impact of the Study:, The persistence of a viable bifidobacteria cells is shorter, but the longest persistence of molecular targets. This factor could be used for origin the faecal pollution in water for the development of microbial source tracking (MST). [source] Loop migration in adult marsh harriers Circus aeruginosus, as revealed by satellite telemetryJOURNAL OF AVIAN BIOLOGY, Issue 2 2010Raymond H. G. Klaassen Loop migration among birds is characterized by the spring route lying consistently west or east of the autumn route. The existence of loops has been explained by general wind conditions or seasonal differences in habitat distribution. Loop migration has predominantly been studied at the population level, for example by analysing ring recoveries. Here we study loop migration of individual marsh harriers Circus aeruginosus tracked by satellite telemetry. We show that despite a generally narrow migration corridor the harriers travelled in a distinct clockwise loop through Africa and southern Europe, following more westerly routes in spring than in autumn. We used the Normalized Difference Vegetation Index (NDVI) to identify potential feeding habitat in Africa. Suitable habitat seemed always more abundant along the western route, both in spring and autumn, and no important stopover site was found along the eastern route. Observed routes did thus not coincide with seasonal variation in habitat availability. However, favourable habitat might be more important during spring migration, when the crossing of the Sahara seems more challenging, and thus habitat availability might play an indirect role in the harriers' route choice. Grid-based wind data were used to reconstruct general wind patterns, and in qualitative agreement with the observed loop marsh harriers predominantly encountered westerly winds in Europe and easterly winds in Africa, both in autumn and in spring. By correlating tail- and crosswinds with forward and perpendicular movement rates, respectively, we show that marsh harriers are partially drifted by wind. Thus, we tentatively conclude that wind rather than habitat seems to have an overriding effect on the shape of the migration routes of marsh harriers. General wind conditions seem to play an important role also in the evolution of narrow migratory loops as demonstrated for individual marsh harriers. [source] Agroforestry management affects coffee pests contingent on season and developmental stageAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2009A. Teodoro Abstract 1,Management of vegetational diversity in agroecosystems is a potentially regulating factor of pest population dynamics and may affect developmental stages in different ways. 2,We investigated the population dynamics of red spider mites, coffee leaf miners, and coffee berry borers in three management types of coffee agroforests: increasing plant diversity from a few shade tree species (simple-shade agroforests), intermediate-shade tree species (complex-shade agroforests) to high-shade tree species (abandoned coffee agroforests) in Ecuador. Furthermore, we studied how changes in agroforestry management affect population stage structure of each coffee pest. 3,Our results show that agroforestry management affected seasonal patterns of coffee pests in that higher densities of red spider mites were observed from August to December, coffee leaf miners from December to February, and coffee berry borers from May to July. Moreover, specific developmental stages of red spider mites, coffee leaf miners, and coffee berry borers differed in their responses to agroforestry management. During all stages, red spider mite reached higher densities in simple-shade agroforests compared with complex-shade and abandoned agroforests. Meanwhile, coffee leaf miner densities decreased from simple-shade to complex-shade and abandoned agroforests, but only for larvae, not pupae. Similarly, only coffee berry borer adults (but not eggs, larvae and pupae) demonstrated a response to agroforestry management. Environmental variables characterizing each agroforestry type proved to be important drivers of pest population densities in the field. 4,We emphasize the importance of considering seasonal differences and population structure while investigating arthropod responses to different habitat types because responses change with time and developmental stages. [source] 59 Utility of the periphyton index of biotic integrity (PIBI) as an indicator of acid mine drainage impacts in southeastern ohioJOURNAL OF PHYCOLOGY, Issue 2003S. E. Hamsher In the Appalachian region, numerous streams are polluted with acid mine drainage (AMD). These waters are sulfate-rich with elevated amounts of total acidity, low pH, and high levels of dissolved metals. Biotic multimetric indices, such as the Periphyton Index of Biotic Integrity (PIBI) have been employed to determine water quality across a variety of environmental conditions and may prove useful for AMD impacts. This study was initiated (1) to evaluate the PIBI for distinguishing AMD impact in streams and (2) to examine whether PIBI scores are impacted by seasonal differences. Twelve AMD and three reference streams were sampled for periphyton in June, August, and October. Water chemistry was collected at least once during the sampling period. Preliminary results showed that PIBI scores were significantly different (p<0.05) among the seasons. In addition, the seasonal trends in PIBI scores among streams were not consistent. The PIBI scores were correlated with six water chemistry variables in August and with at least one variable indicative of AMD in each season sampled. PCA and UPGMA analyses of water chemistry data grouped the streams into five categories: (1) moderately impacted AMD streams with lower total dissolved solids, sulfate, total aluminum, and alkalinity, and higher sulfate; (2) AMD streams with higher alkalinity and lower total aluminum; (3) AMD streams with lower alkalinity and higher total aluminum; (4) reference streams and (5) an outlier reference stream affected by nutrients. Relationships between the groups based on water chemistry and the groups derived from the PIBI will be discussed. [source] GRATELOUPIA DORYPHORA HAS ESTABLISHED RESIDENCY IN RHODE ISLAND WATERSJOURNAL OF PHYCOLOGY, Issue 2000M. M. Harlin Since 1994, when Grateloupia doryphora (Halymeniaceae, Rhodophyta) was first detected in Rhode Island, the species has spread to the northern portions of Narragansett Bay and onto the open coast of Rhode Island Sound. Specimens collected at 5 m depths off North Prudence Island reached 175 cm in length and establish this alga as the largest member of the Florideophyceae on North Atlantic shores. Percent cover of populations is seasonal: highest in fall (September through November) and lowest in spring (March through May). Monthly measurements at three stations in Narragansett Bay show significant seasonal differences (p < 0.01) over two annual cycles. Artificial substrata placed in the field at known periods allowed measurements of growth rates on individual thalli. Laboratory culture clarified the sequence of life history stages that make this species a successful contender for space. [source] Annual pattern of plasma melatonin and progesterone concentrations in hair and wool ewe lambs kept under natural photoperiod at lower latitudes in the southern hemisphereJOURNAL OF PINEAL RESEARCH, Issue 2 2006L. A. Coelho Abstract:, ,To study the annual pattern of plasma melatonin and progesterone concentrations in hair [Santa Inês (SI)] and wool [Romney Marsh (RM) and Suffolk (SU)] ewe lambs kept under natural photoperiods at 21°59,S, 12 ewe lambs (four/breed) were used. For melatonin, blood samples were collected monthly throughout the year at the onset (17:00, 19:00 and 21:00 hr) and end (04:00, 06:00 and 08:00 hr) of the night, and for progesterone the samples were collected in the morning, two to three times a week throughout the year. Plasma melatonin concentrations at different times of the day changed according to the season. In diurnal periods (17:00 and 8:00 hr) no seasonal differences were observed but they became evident in the nocturnal intervals (21:00 and 4:00 hr) and transitional night,day (6:00 hr) times. The patterns of melatonin secretion were higher in winter and autumn than in spring and summer. The patterns of plasma progesterone secretion were affected by interaction between breed and season. There was no seasonal variation in plasma progesterone concentrations for SI females. The progesterone pattern for RM and SU females varied with season. The plasma levels were higher in autumn and winter than in spring and summer. At 21°59,S hair and wool ewe lambs showed the same annual pattern of plasma melatonin concentration while the annual progesterone profiles were quite different. For SI females this pattern was constant along all seasons and for RM and SU females this pattern was higher during autumn and winter than spring and summer. [source] STORM DISCHARGE, LOADS, AND AVERAGE CONCENTRATIONS IN NORTHWEST OHIO RIVERS, 1975,1995,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 2 2001R. Peter Richards ABSTRACT: A computerized technique was developed to identify storm runoff episodes and calculate storm discharges, storm loads, and storm average concentrations for each event in datasets with up to 10,000 records. This technique was applied to four watersheds within the Lake Erie drainage basin and identified between 160 and 250 runoff events in each. Storm event loads and storm event mean concentrations were calculated for each runoff event for suspended solids, total phosphorus, soluble reactive phosphorus, nitrate, and total Kjeldahl nitrogen. The basic characteristics of the resulting data are described, as are systematic differences as a function of watershed size, seasonal differences, and trends over time. Many of the results of this study reflect the importance of nonpoint processes and improvements in agricultural best management practices in these watersheds. [source] Bathing and cleansing in newborns from day 1 to first year of life: recommendations from a European round table meetingJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 7 2009U Blume-Peytavi Abstract Background, Development of the skin barrier continues up to 12 months after birth; therefore, care must be taken when cleansing and bathing infants' skin. Available guidelines for skin care in newborns are, however, limited. In 2007, the 1st European Round Table meeting on ,Best Practice for Infant Cleansing' was held, at which a panel of expert dermatologists and paediatricians from across Europe aimed to provide a consensus on infant bathing and cleansing. Outcomes, Based on discussions at the meeting and a comprehensive literature review, the panel developed a series of recommendations relating to several aspects of infant skin care, including initial and routine bathing, safety while bathing, and post-bathing procedures. The panel also focused on the use of liquid cleansers in bathing, particularly relating to the benefits of liquid cleansers over water alone, and the criteria that should be used when choosing an appropriate liquid cleanser for infants. Alkaline soaps have numerous disadvantages compared with liquid cleansers, with effects on skin pH and lipid content, as well as causing skin drying and irritation. Liquid cleansers used in newborns should have documented evidence of their mildness on skin and eyes, and those containing an emollient may have further benefits. Finally, the panel discussed seasonal differences in skin care, and issues relating to infants at high risk of atopic dermatitis. The panel further discussed the need of clinical studies to investigate the impact of liquid cleansers on skin physiology parameters on newborns' and infants' skin. Conclusions, Bathing is generally superior to washing, provided basic safety procedures are followed, and has psychological benefits for the infant and parents. When bathing infants with a liquid cleanser, a mild one not altering the normal pH of the skin surface or causing irritation to skin or eyes should be chosen. Conflicts of interest M.J. Cork and F. Vanaclocha are advisors to Johnson and Johnson. U. Blume-Peytavi is a member of the advisory board of the ,Penaten Beirat', Johnson & Johnson, Germany. J. Faergemann, C. Gelmetti, J. Szczapa declared to have no conflict of interest. [source] Macrofauna Communities in the Eastern Mediterranean Deep SeaMARINE ECOLOGY, Issue 3 2003Ingrid Kröncke Abstract., During two expeditions with RV ,Meteor' in summer 1993 and winter 1997/98 the structural and functional diversity of the benthic system of the highly oligotrophic eastern Mediterranean deep sea was investigated. The macrofauna communities were dominated by polychaetes even at the deepest stations. The fauna at shallow stations was dominated by surface deposit feeders, whereas subsurface deposit feeders and predators generally increased with depth. A high percentage of suspension-feeding Porifera was found in the Levantine Basin. Mean abundance and number of taxa of both expeditions were significantly correlated to depth and distance to the nearest coast as well as to the total organic carbon (TOC) content in sediments. Numbers of taxa and abundance decreased generally with depth, although lowest numbers were not found at the deepest stations but in the extremely oligotrophic Levantine and Ierapetra Basin. Biomass measured during the second cruise was extremely low in the Ierapetra Basin and comparable to other extreme oligotrophic seas. The significant correlations found for TOC contents and macrofauna with distance to coast during both expeditions apparently reflect the role of hydrographically governed transport of organic matter produced in coastal regions into greater and extreme depths of the Mediterranean Sea. Seasonal differences in macrofauna communities due to seasonal differences in food supply were not found. However, recent large-scale hydrographic changes (Eastern Mediterranean Transient, EMT) might change the oligotrophy and, thus, the structure of the benthic communities in the Eastern Mediterranean deep sea. [source] | ||||||||||||||||||||||||||||||||||||||||