Search results for "Season"

Alternative discourses in science fiction: human cloning in Glory Season (1993) by David Brin

2005

L'Oscillation de Madden-Julian et la variabilité pluviométrique régionale en Afrique Subsaharienne

2007

The role of the Madden-Julian Oscillation ("MJO") on rainfall variability in Sub-Saharan Africa is examined, based on daily rain-gauge records and the NCEP-DOE AMIP-II reanalyses. The convective and dynamical signal associated with the MJO is extracted using two differing methodologies, the BMRC daily indices (Wheeler & Hendon 2004) on the one hand, and a Local Mode Analysis ("LMA", Goulet & Duvel 2000) on the other hand. The temporal variability of the MJO (in terms of period, amplitude, seasonality and location of the convective anomalies) is first analysed. Though the overall amplitude of the signal is not related to El Niño, the oscillations occurring under El Niño (La Niña) conditions …

Physical Activity Levels in Preschool Children During Winter and Summer

2019

Source at https://fysioterapeuten.no/Tidsskrifter. Bakgrunn: Studier nasjonalt og internasjonalt indikerer at barn i alderen tre til fem år ikke oppnår retningslinjene for anbefalingene (2014) om minimum 60 minutter med moderat til høy fysisk aktivitet (MVPA) per dag. Studiens hovedmål var å undersøke fysisk aktivitetsnivå hos barnehagebarn i tre barnehager i alderen tre til fem år i en periode om vinteren og en periode om våren/sommeren. Metode: Fysisk aktivitet ble målt i barnehagetiden fra mandag til onsdag med aktivitetsmåleren Actigraph GT3X. Aktivitetsnivået ble kategorisert ut fra antall akselerometer- tellinger/min, hvor hovedvariabelen var tid i moderat til høy fysisk aktivitet (MV…

Edaphyc characteristics and floristic composition of the seasonally dry forest la menta and timbes, Piura Region, Peru

2011

Con el objetivo de contribuir al conocimiento de los ecosistemas naturales del país, se determinó las características edáficas y la composición florística del bosque estacionalmente seco (La Menta, 04º 43' 55" LS y 80º 04' 55" LO, provincia de Piura y Timbes, 04º 44' 58" LS y 80º 03' 33" LO, provincia de Ayabaca), ambos en la región Piura, Perú. El área de estudio abarcó una extensión aproximada de 6 000 hectáreas en un rango altitudinal entre 350 m a 1 350 m. En cada bosque se muestrearon 5 transectos de 10 x 50 m a intervalos de 20 m, sumando un total de 2 500 m². El análisis de suelo reveló niveles bajos de materia orgánica, nitrógeno y potasio y medios de fósforo asimilable. Estos suelo…

Gulf of Maine shells reveal changes in seawater temperature seasonality during the Medieval Climate Anomaly and the Little Ice Age

2011

article i nfo In this study, we use subannually resolved oxygen isotope values of fossil (dead-collected) and modern (live- caught) bivalve shells (Arctica islandica L.) from the northwestern Atlantic (Gulf of Maine, USA) to reconstruct past seasonal changes in seawater temperature. Our results indicate decreased seasonal temperature amplitude of about 1.6 °C (or ∼21%) during Medieval times (ca. AD 1033-1062) compared to shells from the early Little Ice Age (ca. AD 1321-1391) and during the late 19th century (AD 1864-1886). Additionally, seasonal oxygen isotope data suggest that summers were cooler and winters were warmer in the Gulf of Maine during the 11th century compared to summers and …

Mate fidelity and coloniality in waterbirds: a comparative analysis

1998

Increased opportunities for information are one potential benefit of sociality. We apply this idea to the advantages of colonial breeding in bird species that are typically monogamous within a breeding season but often form new pair-bonds in subsequent seasons. Individuals may benefit from nesting in colonies at high density by identifying good-quality potential alternative mates among their neighbours. The opportunities for finding a better mating option are likely to increase with colony size and density. We tested this prediction with a comparative analysis of the association between mate fidelity and coloniality in waterbirds (wading birds and seabirds), where there is wide variation in…

Myxosporea parasites in roach, Rutilus rutilus (Linnaeus), from four lakes in central Finland

1991

Ten myxosporean species belonging to three families were found in roach, Rutilus rutilus (Linnaeus), obtained in 1985 and 1986 from four lakes in central Finland which are connected to each other, but differ in water quality. One of the lakes is polluted by paper and pulp mill effluent, two are eutrophic and one is oligotrophic and still in its natural state. Eight species were found in all the lakes. The most common species were Myxidium rhodei Leger, 1905, Myxobolus muelleri Butschli, 1882 and Myxobolus pseudodispar Gorbunova, 1936 with prevalences varying between 66–80, 16–31 and 32–59%, respectively, in the four lakes. The largest difference in myxosporean prevalence between lakes was f…

Seasonality of coastal phytoplankton in the Baltic Sea: Influence of salinity and eutrophication

2005

Abstract In this study long-term (1984–2001) phytoplankton and physico-chemical monitoring data representing different salinity regimes of the Baltic Sea were compiled from HELCOM, national and regional databases. The aim was to define seasonal succession patterns of phytoplankton in seven different areas of the Baltic sea, characterised by different salinity, climate, and trophic conditions and to delineate a set of phytoplankton community indicators that are independent of season and salinity, but indicative of trophic status of different coastal areas. The cluster analysis of the combined data set resulted in eight phytoplankton community types, common for all locations, and characterise…

Behavioural responses of Eurasian treecreepers, Certhia familiaris, to competition with ants

1997

Competition for a specific resource that is essential for the survival of both the competitors may be intense even between very dissimilar taxa. However, the importance of the effects caused by such interspecific competition has seldom been emphasized. These effects can appear as differences in individual foraging behaviour during the breeding season, which can result in critical variation in fitness. In this study we examined the effects of wood ants (Formica rufa group) on the abundance of other invertebrates on tree trunks and on the foraging site selection of breeding Eurasian treecreepers, which use the same habitat as wood ants. Arthropods were scarcer on the trunks with ants present;…

Intercohort competition causes spatial segregation in brown trout in artificial streams

1999

When together in a flume, 13-cm LS (age-1) trout appeared to increase their activity and behaved more aggressively, whereas 10-cm LS (age-0) trout tended to move less and were rarely aggressive in the presence of the larger size class. Both size classes were less mobile and preferred lower water velocities in winter than in summer, and increased their use of instream cover in winter. When both size classes were present, only small trout decreased their use of low water velocities and cover. The results indicate that intercohort competition may cause spatial segregation among size groups of brown trout, especially in winter when trout attempt to minimize their maintenance costs.