The trial was conducted in south-western France at the Regional Centre for Organic Agriculture Trials, at Auch (32) in 2006, on a deep limestone clay silt soil with high water- holding capacity (Table 2). Two sowing dates were used to generate temperature variations during seed development. The trial was sown at a density of 7.1x10 4 plants/ha on April, 26 th for the conventional sowing date (CSD) and on June, 1 st for the late sowing dates (LSD). The development of the crop was monitored weekly using the main phenological stages E, R1, R5.1, R6, R8 and R9 as described by Schneiter and Miller (1981). The trial was conducted as a complete randomised block design with 32 treatments (16 genotypes x 2 sowing dates) with 3 replications. Plot size was 16 m², 10 plants in each plot were bagged before flowering to obtain seed by self-pollination.
A tool for calculating cyclical transient hygrothermal stress in laminated composite plates is presented. It relies on a detailed calculation of the hygrothermal fields, described by the classical Fick’s law, obtained through analytical and finite difference methods and the classical lamination theory, extended for taking into account transient conditions. The state of stress generated by cyclical environmentalconditions due to a supersonic flight is simulated and some discussion about the relevance of such stress is provided.
produced realistic FPSO motions in the different environmentalconditions for the evaluation of the offshore evacuation system.
Tests were conducted in five environments made up of waves and wind and for the FPSO in its ballast loading condition and with heading to the waves of 20 o and 57 o to the wind. The environments corresponded to those proposed for the test series. The results from the small environment produce little or no motions on the FPSO. Also some of the data collected for this environment was very noisy which made analysis difficult and very unreliable. A decision was made to omit this environment from the comparisons. The fresh and strong breeze along with the moderate and fresh gales environments will be used for the comparison of the resulting motions of the FPSO in the current setup.
A further hypothesis is that the trait values required to follow optimal environmentalconditions might differ from those required to survive in suboptimal conditions, resulting in a possible trade- off between investment in either capacity (Aubin et al., 2016) (Table 1 II). For instance, following optimal environmentalconditions might re- quire directed dispersal (e.g., through animals) and local competitive dominance through efficient resource acquisition (e.g., high specific leaf area or high leaf area), large seeds, and large stature. Optimal en- vironmental conditions might also enable efficient interactions with reliably available specialized pollinators, for example, through special- ized flowers (Castro- Urgal & Traveset, 2016). In contrast, persisting under suboptimal environmentalconditions might require accessing a wide range of sites through the undirected dispersal of small seeds by the wind, and tolerating particularly extreme abiotic conditions through reduced water loss (e.g., small specific leaf area) and effi- cient water acquisition (e.g., deep roots and wide root- system) (Burns, 2004; Liu et al., 2014; Muller- Landau et al., 2008; Padilla & Pugnaire, 2007). Persisting in suboptimal environmentalconditions might also be favored by dish- shaped, shallow flowers avoiding dependency on specialized interactions with pollinators as these pollinators might be unavailable (Castro- Urgal & Traveset, 2016).
Abstract: Phytoplankton samples from 23 Chilean freshwater bodies (lotic and lentic) monitored by the General Water Directorate and by the EULA Center were examined to identify the diversity, optimal conditions and tolerance of planktonic cyanobacteria to different conditions. We selected ecosystems between 34 - 41° S latitude with different environmentalconditions (trophic status) and human intervention in the watershed (land usage). Cyanobacteria and overall phytoplankton were identified and their abundance and biovolume were determined using the Utermohl method. In seven lakes or rivers with visible blooms, samples were identified using a polyphasic approach, in which morphological, ecological and molecular markers (rRNA loci) were integrated.
There is daily air traffic through the Arctic, so it is important to consider mean and extreme
environmentalconditions throughout the year as accidents may occur any time. However, cruise ship traffic through the Canadian Arctic is typically between the months of July to late September or early October, where the environmentalconditions are less severe.
Individual hatch date influences survival and age of first breeding across a variety of bird species (e.g., Spear and Nur 1994, Verboven and Visser 1998, Pre´- vot-Julliard et al. 2001). Hatch date is negatively re- lated to recruitment in geese (Cooke et al. 1984, Se- dinger et al. 1995) and ducks (Dawson and Clark 2000), but it is not clear whether this is an effect of hatch date on juvenile survival (Owen and Black 1989, Cooch et al. 1993, Schmutz 1993, Lepage et al. 2000) or on age of first breeding. Environmentalconditions at the start of the breeding season may affect recruitment if they result in delayed nesting (Prop and de Vries 1993, Le- page et al. 1996), restricted access to feeding (Gauthier and Tardif 1991, Choinie`re and Gauthier 1995, Ganter and Cooke 1996), or generally reduce breeding effort and success (Barry 1962, Skinner et al. 1998). Predator abundance and activity at the colonies during the pre- breeding period can also induce birds to forego breed- ing (Spaans et al. 1998).
The chamber was airtight and environmentalconditions including temperature, RH, air flow rate and turbulence were under control. For this purpose, temperature and humidity sensors (Honeywell RH/T sensor HIH-4602) were located inside and outside the chamber. A differential pressure sensor was also used to measure the pressure difference between the outer chamber and the room. The signals were sent to the DAS, and data were sampled in one minute intervals to
coupled series of processes comprising the cessation or reduction of leaf growth, the complete or partial senescence of herbage and in some cases the endogenous dehydration of meristems expressed even under non-limiting moisture conditions. However, it is always expressed under the environmentalconditions typical of Mediterranean summers (Volaire and Norton, 2006). Dormancy was not observed in the earlier drought tolerance work of the annual crop physiologists (Ludlow, 1989) so that its role in enhancing drought tolerance of perennial plants has, in contrast to other strategies, been particularly neglected. The summer dormancy trait commonly occurs in those temperate perennial grass species of Mediterranean origin found in regions usually experi- encing summer dry periods of four months or more (Cooper, 1963). In the Mediterranean Basin most of these regions are found in North African and Middle Eastern countries (Neal-Smith, 1955). Other research has shown that the trait also exists in North American species growing in similar environments (Laude, 1953). Observations suggest that the trait exists at least in the Australian grasses, Austrodanthonia caespitosa and Elymus scaber (C. Waters and J. Virgona pers. com.) from summer-dry environments although this still requires experimental confirmation.
Stylophora pistillata revealed no overlap of the isotopic niches for the host and symbiont from different
locations (unpublished data), suggesting that these coral colonies are supported by different core resources. Moreover, the isotopic niche of higher latitude coral colonies was larger than those from the lower latitudes (unpublished data), highlighting a certain trophic plasticity that may be related to more variable environmentalconditions in the higher latitudes. Analyses of additional species and locations will provide essential insights into the trophic strategies of reef-building corals and how these species might adjust their nutrition in response to environmental changes.
Trophic plasticity of scleractinian corals under contrasted environmentalconditions: evidence from stable isotope analysis
STURARO Nicolas 1,2 , HSIEH Chien Hsun Eric 1 , LIU Ling-Wen 1 , WANG Pei-Ling 1 , DENIS Vianney 1
(1) Institute of Oceanography, National Taiwan University (2) Laboratory of Oceanology, University of Liege
Stylophora pistillata revealed no overlap of the isotopic niches for the host and symbiont from different
locations, suggesting that these coral colonies are supported by different core resources. Moreover, the isotopic niche of higher latitude coral colonies was larger than those from the lower latitudes, highlighting a certain trophic plasticity that may be related to more variable environmentalconditions in the higher latitudes. Analyses of additional species and locations will provide essential insights into the trophic plasticity of scleractinian corals and how these species might adjust their nutrition in response to environmental changes.
variability for sterol content has been reported in soybean (Yamaya, Endo, Fujimoto & Kitamur, 2007) and in cereals (Nurmi, Nyström, Edelman, Lampi & Piironen 2008; Alignan et al., 2009). Effects of genotype on sunflower seed oil and protein contents have been widely reported, but, so far, there have been no studies of genotypic variability of sterol content. No information is available on interactions between genetic factors and environmentalconditions affecting sterol concentration and composition in sunflower seed. Knowledge of the genetic variability available is essential to make possible heredity and heritability studies and mapping of genes controlling sterol content. Although Roche et al. (2006) described the behaviour of genetic variability of total sterol contents, only 3 genotypes were analyzed in interaction with water stress. This work did not study the sterol composition. Considering the large genetic potentialities of sunflower, it therefore appears crucial to enlarge representative genetic backgrounds and to study genotype*environment interactions.
Each family showed a different response to variation in environmental and food conditions.
Differences in nature and extent of trophic plasticity could lead to different impacts of future
environmental changes on each family’s feeding habits, biology, and ultimately distribution.
Trophic plasticity of Antarctic echinoids under contrasted environmentalconditions
A series of large scale model experiments of lifeboat evacuation from a floating platform were done at the National Research Council of Canada’s Institute for Marine Dynamics (NRC/IMD). The main objective of the experiments was to measure evacuation performance as a function of environmentalconditions. Risk assessment is a design imperative and a regulatory requirement in many jurisdictions, but published quantitative data on lifeboat evacuation are sparse (e.g. Spouge 1999), which hampers the design process. The discussion here is in the context of offshore petroleum installation safety, although the results are relevant to ship safety. Previous work on evacuation system evaluation using model tests has been reported by Rutgersson and Tsychkova (1999) for ships, for example, and by Campbell
Assuming that functional feeding traits represent a strong link between the environment, isotopic niches and energy pathways in food webs (Gravel et al., 2016), we predict that any variation in en- vironmental conditions (i.e., CC, detrital concentration [DC] and/or habitat size) that affects the functional trait composition within local communities would also change the attributes of isotopic niches (e.g., richness, evenness; Prediction 1, P1). For example, food webs fuelled by both allochthonous and autochthonous resources would be expected to have a higher diversity of functional traits related to the processing of coarse and fine organic matter and so may display larger isotopic niches. Similar to that, as odonates are top predators, we predict they will show shifts in dietary composition as the under- lying food webs change with environmentalconditions (Prediction 2, P2; Delibes et al., 2015). We also predict that bromeliad food webs subject to different environmentalconditions (e.g., changes in CC within a site) may occupy different areas of isotopic space because the basal resources differ, which may broaden the metacommunity- level isotopic niche (i.e., the isotopic niche of all bromeliads within a site; Prediction 3, P3; Delibes et al., 2015). At last, we expect that metacommunities in different biogeographic regions will have simi- lar isotopic niches in similar environmentalconditions. However, if dispersal limits the distribution of species that can exploit certain re- sources, then metacommunities in different locations could instead occupy distinct portions of the isotopic niche (Prediction 4, P4). For example, odonates generally do not occur in bromeliads in isolated, cold or high elevation sites, suggesting that the engulfing predator functional niche will be missing from such species pools, reducing the isotopic niche of the community. Partitioning of isotopic niche effects into functional groups vs. environmental effects may help elucidate such patterns. The above predictions, the metrics used in the study and their biological meaning are detailed in Table 1. 2 | MATERIALS AND METHODS
The mangrove vegetation is the major organic source in these environments. Its distribution is the other main parameter determining the environmentalconditions and OM evolution. It supplies organic carbon into the sediment, via the litters, under the form of fresh ligno-cellulosic debris. We characterized the OM evolution by the following markers: 1) palynofacies constituants %, 2) TOC%, IH, C/N and 13 ∂C values, 3) total sugars and phenols %, 4) (Ad/Al) v and S/V ratios, 5) fucose and rhamnose contents. Their distribution obeys to a
et al., 2000; Sohn and Farrar, 2000), χ²-test based on realization analysis (Basseville et al., 2000), and more recently a novelty analysis based on a Kalman model (Yan et al., 2004a).
In most of the previous analyses, vibration characteristics of structures were estimated with the assumption of a constant environment. However, in practical situations, structures are often subject to changes in environmental and operational conditions (e.g. temperature, temperature gradients, humidity, wind, traffic, etc.), which may mask the changes caused by structural damages. If the effect of these environmentalconditions is not taken into account in the damage detection process, false-positive or negative damage diagnosis may occur so that vibration-based health monitoring becomes unreliable. Accordingly, during the last years, structural dynamicists have become increasingly concerned with modal parameter variability due to environmentalconditions (see for instance Wahab and De Roeck, 1997; Kullaa, 2001; Sohn et al., 2001; Ko et al., 2003)
conditions in these five ecosystems had either negatively affected the whole community,
especially the high trophic level and/or vulnerable species, or had favored species at lower
trophic levels in the past few decades. On the other hand, effects of environmentalconditions on
communityS were positive in the Barents Sea, eastern English Channel, New Zealand Chatham,
Stable isotope ratios of animals are influenced by many ecological, physiological, and environmental factors (Boecklen et al. 2011 ). Among those, factors involving (1) differences in consumer foraging ecology and trophic resource exploitation and (2) baseline shifts and variation in primary producers and/or organic matter pool isotopic composition are likely to have strong effects on consumer isotopic composition. Here, Schizasteridae carbon isotopic ratios showed inter-location variation, with increasing (i.e. less negative) d 13 C following a north–south gradient. On the one hand, sea urchins could feed on different sources in each zone, favouring more 13 C-depleted items in Drake Passage than in Bransfield Strait or in Weddell Sea. However, gut content analyses suggested that Schizasteri- dae show similar trophic behaviour and feed on sediment and associated organic matter in all three regions. On the other hand, the isotopic composition of sediment-associ- ated organic matter (hereafter SOM) in these three regions is likely to vary. These three regions are indeed charac- terized by widely different environmentalconditions, and notably by increasing presence of sea ice from north to south (Bracher and Huntemann 2015 ; Dorschel et al. 2015 ; Table 1 ). Organic matter associated with Antarctic sea ice is very rich in 13 C, and sea ice inputs to sediment can cause an increase in SOM d 13 C (Gibson et al. 1999 ). Higher SOM d 13 C in locations where sea ice is more present could in turn cause higher sea urchin d 13 C. Elevated d 13 C values have indeed been recorded for meiobenthic copepods and nematods from Lazarev Sea locations heavily influenced by sea ice (Veit-Ko¨hler et al. 2013 ). Settling this issue would require precise knowledge of isotopic composition of SOM in each sampling location. However, combination of insights drawn from gut content examination and stable isotope analysis suggest that Schizasteridae feeding habits are similar in Drake Passage, Bransfield Strait and Weddell Sea, and that they are bulk sediment feeders relying on SOM. The variability in their isotopic compo- sition (Fig. 2 ) is likely related to baseline shifts in SOM isotopic composition rather than actual inter-regions dif- ferences in feeding habits.