Search results for "ETL"
showing 10 items of 431 documents
Carbon emission along a eutrophication gradient in temperate riverine wetlands: effect of primary productivity and plant community composition
2016
International audience; 1. Eutrophication increases primary productivity and favours the predominance of floating vegetation in wetlands. Carbon (C) fluxes in wetlands are strongly driven by primary productivity and can differ by vegetation type. However, to the best of our knowledge, the role of eutrophication in C fluxes has rarely been assessed. 2. Consequently, we aimed to measure the seasonal variation in carbon dioxide (CO2) and methane (CH4) fluxes at six aquatic sites in four temperate wetlands, ranging along a gradient of sediment total phosphorus content, and determine whether C fluxes correlate with above-ground net primary productivity (ANPP) and plant community composition alon…
Emergence phenology and ecology of aquatic and semi-terrestrial insects on a boreal raised bog in Central Finland
1988
Emergence of peatland insects was studied in Central Finland by sampling insects on a raised bog with tent traps from five different surfaces: muddy hollow without vegetation; hollow covered with Sphagnum; deep (0.7-0.9 m) open-water pool; shallow (about 0.3 m) pool with bottom covered by Carex vegetation; shallow (about 0.3 m) pool with bare muddy bottom. The material was collected at two-days intervals from 13 May until 31 August in 1981. Biomass emerging from the sites varied considerably. In general, aquatic sites were clearly more productive than semi-terrestrial sites. Corrected total biomass values for deep pools, shallow Carex pools, and shallow mud pools were 2.471, 1.066, and 0.51…
Lukiolaiset internetlähteiden luotettavuuden arvioijina
2017
Internetin käytön yleistyminen ja saatavilla olevan informaation jatkuva lisääntyminen on tehnyt tiedon luotettavuuden arvioinnista entistä vaikeampaa. Internetlähteiden käyttö lukio-opinnoissa on myös lisääntynyt. Tämän tutkimuksen tarkoituksena oli selvittää, kuinka hyvin lukiolaiset osaavat arvioida internetlähteiden luotettavuutta. Tutkimus on osa ARONI-tutkimushanketta ja siihen osallistui 186 Hämeenlinnan ja Riihimäen alueiden lukiolaista. Lukiolaiset tekivät internetlukutaitoja mittaavan tehtävän, jonka yhtenä osana tuli etsiä kaksi internetlähdettä rokottamisen pakollisuutta kos-kevaa selvitystä varten. Lähteiden luotettavuus tuli arvioida asteikolla luotettava - melko luotettava - …
Complémentarité des données de télédétection pour l'analyse des transformations de l'occupation du sol dans des zones humides urbaines. Application a…
2008
International audience; Dans le cadre d'un programme ECOS-Nord, notre étude analyse les transformations récentes de l'occupation du sol sur deux zones humides urbaines : les hortillonnages d'Amiens et les chinampas de Mexico. Malgré des contextes différents, ces deux espaces sont les supports d'usages et de dynamiques très similaires : des techniques identiques d'agriculture sur l'eau et un déclin de l'activité agricole au XXe siècle au profit de celle des loisirs. L'objectif est double : identifier et quantifier les changements sur chacun des sites, puis les confronter de façon à mettre en évidence les points communs et les spécificités locales, tant dans la nature des changements, que dan…
Photoperiodic effects on diapause-associated gene expression trajectories in EuropeanLeptinotarsa decemlineatapopulations
2014
Behavioural and physiological changes during diapause, an important strategy of insects for surviving harsh seasonal conditions, have been intensively studied. The genetic and molecular mechanisms underpinning diapause development are less well known. We took a candidate gene approach to study prediapause gene expression patterns in the Colorado potato beetle (Leptinotarsa decemlineata), an invasive insect that has rapidly spread northwards to high seasonality environments. Newly eclosed beetles originating from southern (Italy) and northern (Russia) Europe were reared under short- [12 h light (L):12 h dark (D)] and long-day (18L:6D) photoperiods for 10 days. This time period includes the s…
EURO-CORDEX regional climate model simulation of precipitation on Scottish islands (1971-2000): model performance and implications for decision-makin…
2017
Due to their scale and complex topography, islands such as the Hebrides and Shetland Islands are not completely resolved by global climate models, which may impact the quality of data that can be provided about future climate in such locations. In principle, dynamical downscaling may provide helpful additional detail about future local climate. However, there is also the potential for error and uncertainty to cascade through to the regional simulation. Here, we evaluate the simulative skill of the EURO-CORDEX regional climate model ensemble on regional and local scales in the Hebrides and Shetland Islands, and consider the potential for such models to aid decision-making in island settings,…
Exploratory behaviour is not related to associative learning ability in the carabid beetle Nebria brevicollis
2020
Recently, it has been hypothesised that as learning performance and animal personality vary along a common axis of fast and slow types, natural selection may act on both in parallel leading to a correlation between learning and personality traits. We examined the relationship between risk-taking and exploratory behaviour and associative learning ability in carabid beetle Nebria brevicollis females by quantifying the number of trials individuals required to reach criterion during an associative learning task (‘learning performance’). The associative learning task required the females to associate odour and direction with refugia from light and heat in a T-maze. Further, we assessed learning …
The effect of peatland drainage and restoration on Odonata species richness and abundance
2015
Background Restoration aims at reversing the trend of habitat degradation, the major threat to biodiversity. In Finland, more than half of the original peatland area has been drained, and during recent years, restoration of some of the drained peatlands has been accomplished. Short-term effects of the restoration on peatland hydrology, chemistry and vegetation are promising but little is known about how other species groups apart from vascular plants and bryophytes respond to restoration efforts. Results Here, we studied how abundance and species richness of Odonata (dragonflies and damselflies) respond to restoration. We sampled larvae in three sites (restored, drained, pristine) on each o…
Experimental evidence suggests that specular reflectance and glossy appearance help amplify warning signals
2017
AbstractSpecular reflection appears as a bright spot or highlight on any smooth glossy convex surface and is caused by a near mirror-like reflectance off the surface. Convex shapes always provide the ideal geometry for highlights, areas of very strong reflectance, regardless of the orientation of the surface or position of the receiver. Despite highlights and glossy appearance being common in chemically defended insects, their potential signalling function is unknown. We tested the role of highlights in warning colouration of a chemically defended, alpine leaf beetle, Oreina cacaliae. We reduced the beetles’ glossiness, hence their highlights, by applying a clear matt finish varnish on thei…
Interactions between willows and insect herbivores under enhanced ultraviolet-B radiation
2002
We studied the effects of elevated ultraviolet-B radiation on interactions between insect herbivores and their host plants by exposing two species of phytochemically different willows, Salix myrsinifolia and S. phylicifolia, to a modulated increase in ultraviolet radiation in an outdoor experiment and monitoring the colonisation of insect herbivores on these willows. We examined the effect of increased ultraviolet-B (UV-B) radiation on (1) the quality of willow leaves, (2) the distribution and abundance of insect herbivores feeding on these willows, (3) the resulting amount of damage, and (4) the performance of insect larvae feeding on the exposed plant tissue. Six clones of each of the two…