Search results for "Mod"
showing 10 items of 39605 documents
AlomySys: Modelling black-grass (Alopecurus myosuroides Huds.) germination and emergence, in interaction with seed characteristics, tillage and soil …
2006
International audience; Weed emergence models are increasingly necessary to evaluate and design cropping systems. The model AlomySys was developed for a frequent and harmful weed, i.e. Alopecurus myosuroides Huds. [Colbach, N., Dürr, C., Roger-Estrade, J., Caneill, J., 2005a. How to model the effects of farming practices on weed emergence. Weed Res. 45, 2–17; Colbach, N., Dürr, C., Roger-Estrade, J., Chauvel, B., Caneill, J., 2005b. AlomySys: modelling blackgrass (Alopecurus myosuroides Huds.) germination and emergence, in interaction with seed characteristics, tillage and soil climate. I. Construction. Eur. J. Agronomy] and is based on sub-models predicting (a) soil environment (climate, s…
Merging cranial histology and 3D-computational biomechanics : A review of the feeding ecology of a Late Triassic temnospondyl amphibian
2021
Finite Element Analysis (FEA) is a useful method for understanding form and function. However, modelling of fossil taxa invariably involves assumptions as a result of preservation-induced loss of information in the fossil record. To test the validity of predictions from FEA, given such assumptions, these results could be compared to independent lines of evidence for cranial mechanics. In the present study a new concept of using bone microstructure to predict stress distribution in the skull during feeding is put forward and a correlation between bone microstructure and results of computational biomechanics (FEA) is carried out. The bony framework is a product of biological optimisation; bon…
Condition-dependent ecdysis and immunocompetence in the amphipod crustacean, Gammarus pulex.
2010
The exoskeleton of arthropods forms an efficient protection against pathogens, but this first line of defence is periodically weakened during ecdysis, increasing the opportunity for surrounding pathogens to invade the body cavity. Since the richness of pathogens in the environment can be spatially and temporally variable, arthropods may have a fitness advantage in moulting in a place and time of low infection risk. Consistent with this hypothesis, we found that the amphipod crustacean, Gammarus pulex , exhibits temporal adjustment of the moult cycle in response to elevated risks of infection. Interestingly, this phenomenon is variable between two populations and independent of levels of im…
Small but smart: the interaction between environmental cues and internal state modulates host-patch exploitation in a parasitic wasp
2007
International audience; The reproductive success of insect parasitoids depends on two activities, searching for hosts to obtain immediate fitness rewards (offspring) and searching for food to extend life span and enhance future reproductive opportunities. Models suggest that to deal with this trade-off and to cope with the variability of the resources they depend on, parasitoids should simultaneously integrate information originating from three distinct sources: host and food availabilities in the environment (environmental information) and the metabolic reserves of the parasitoid (internal information). We tested whether, in the parasitic wasp Venturia canescens, these three types of infor…
Effect of Different Modified Atmosphere Packaging on the Quality of Mulberry Fruit (Morus alba L. cv Kokuso 21)
2021
The control of temperature and gas composition is essential to maintain the fresh flavor and quality of perishable fruits like mulberry. This study presented a modified atmosphere experiment (MAP) for fresh fruit showing the potential benefits of innovative gas mixing with argon. The effects of MAP were studied on the physicochemical and qualitative attributes of mulberry preserved at4±1°C and90±5%R.H. Fresh mulberries were packaged with different gas combinations: MAP1 (4%O2+6%CO2+90%N2), MAP2 (10%O2+5%CO2+85%Ar), CTR1 (20.9%O2+0.04%CO2), and CTR2 (10%O2+5%CO2+85%N2). Changes in quality parameters were evaluated after 0, 4, 8, and 12 days of storage. Mulberries packaged with MAP had a lowe…
Experimentally induced community assembly of polypores reveals the importance of both environmental filtering and assembly history
2019
The community assembly of wood-inhabiting fungi follows a successional pathway, with newly emerging resource patches being colonised by pioneer species, followed by those specialised on later stages of decay. The primary coloniser species have been suggested to strongly influence the assembly of the later-arriving community. We created an artificial resource pulse and studied the assembly of polypores over an 11yr period to ask how the identities of the colonising species depend on the environmental characteristics and the assembly history of the dead wood unit. Our results support the view that community assembly in fungi is a highly stochastic process, as even detailed description of the …
Fuzzy quantification of common and rare species in ecological communities (FuzzyQ)
2021
International audience; Most species in ecological communities are rare, whereas only a few are common. This distributional paradox has intrigued ecologists for decades but the interpretation of species abundance distributions remains elusive.We present Fuzzy Quantification of Common and Rare Species in Ecological Communities (FuzzyQ) as an R package. FuzzyQ shifts the focus from the prevailing species-categorization approach to develop a quantitative framework that seeks to place each species along a rarity-commonness gradient. Given a community surveyed over a number of sites, quadrats, or any other convenient sampling unit, FuzzyQ uses a fuzzy clustering algorithm that estimates a probab…
Habitat associations drive species vulnerability to climate change in boreal forests
2016
Species climate change vulnerability, their predisposition to be adversely affected, has been assessed for a limited portion of biodiversity. Our knowledge of climate change impacts is often based only on exposure, the magnitude of climatic variation in the area occupied by the species, even if species sensitivity, the species ability to tolerate climatic variations determined by traits, plays a key role in determining vulnerability. We analyse the role of species’ habitat associations, a proxy for sensitivity, in explaining vulnerability for two poorly-known but species-rich taxa in boreal forest, saproxylic beetles and fungi, using three IPCC emissions scenarios. Towards the end of the 21…
Environment-sensitivity functions for gross primary productivity in light use efficiency models
2022
International audience; The sensitivity of photosynthesis to environmental changes is essential for understanding carbon cycle responses to global climate change and for the development of modeling approaches that explains its spatial and temporal variability. We collected a large variety of published sensitivity functions of gross primary productivity (GPP) to different forcing variables to assess the response of GPP to environmental factors. These include the responses of GPP to temperature; vapor pressure deficit, some of which include the response to atmospheric CO2 concentrations; soil water availability (W); light intensity; and cloudiness. These functions were combined in a full fact…
Alder pollen in Finland ripens after a short exposure to warm days in early spring, showing biennial variation in the onset of pollen ripening
2017
Abstract We developed a temperature sum model to predict the daily pollen release of alder, based on pollen data collected with pollen traps at seven locations in Finland over the years 2000–2014. We estimated the model parameters by minimizing the sum of squared errors (SSE) of the model, with weights that put more weight on binary recognition of daily presence or absence of pollen. The model results suggest that alder pollen ripens after a couple of warm days in February, while the whole pollen release period typically takes up to 4 weeks. We tested the model residuals against air humidity, precipitation and wind speed, but adding these meteorological features did not improve the model pr…