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Environmental Economics and Policy Studies - While the EU is working toward the implementation of the world’s first Carbon Border Adjustment (CBA) Mechanism, a gap remains between the ways in... 相似文献
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G. Baudry S. Bernard P. Gillard 《Journal of Loss Prevention in the Process Industries》2007,20(4-6):330-336
Some results of determination of ignition energies for an aluminium powder with various oxide contents are presented. Common use of processes like high-speed cutting produce explosive dust clouds, so that we focused this study on hazard of metallic powders. An industrial aluminium powder has been used for this work. An original process, based on the principle of electrochemical anodisation, has been developed to increase, under control, the oxide coating of particles.
The sensitivity study to spark ignition was performed in an Hartmann explosion tube of 1.3L. The Langlie test method was applied to evaluate the energies leading to a probability of ignition of 50% (E50) of the selected samples. The results confirm that the ignition energies increase with the oxide content of the powder. 相似文献
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Julie Marmet Beno?t Pisanu Jean-Louis Chapuis Gwena?l Jacob Emmanuelle Baudry 《Behavioral ecology and sociobiology》2012,66(11):1449-1457
While sexual selection in mammals with female defense systems has historically received considerable attention, much less is known about the factors affecting reproductive success in mammalian species with scramble competition mating systems. Using mark–recapture techniques and DNA microsatellite loci to assign parentage, we examined the mating system and factors affecting the variation of the annual reproductive success in an introduced population of the Siberian chipmunk, Tamias sibiricus, a small, monomorphic, solitary squirrel. Our analyses showed that breeding females were spatially dispersed, setting the stage for a scramble competition mating system. Male reproductive success was positively associated with the size of the home range. The strength of sexual selection on this behavioral trait was very strong, equaling previous estimates for morphological traits in female defense mating systems. These findings suggest that a behavioral trait, space use, strongly influences the annual reproductive success in males, which is consistent with expectations in a scramble competition mating system. In both sexes, reproductive success was influenced by habitat, with twice as many juveniles produced in semi-open than in closed habitat, possibly due to differences in food availability between the two habitats. 相似文献
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Symbioses between dinoflagellates in the genus Symbiodinium (commonly referred to as zooxanthellae) and scleractinian corals are an essential feature for the maintenance of coral reefs.
The fine-scale diversity and population structure of the zooxanthellae inhabiting the coral Pocillopora meandrina, a major reef building species in Polynesia, was examined. We used two polymorphic microsatellites to study seven populations
from the South Pacific, whose host structuring has been previously investigated. The symbionts of P. meandrina showed high levels of diversity, with more than one zooxanthella genotype being identified in most of the host individuals.
Genetic differentiation between symbiont populations was detected at a large scale (2,000 km) between the Tonga and the Society
Archipelagos. Within the Society Archipelago, the two most remote populations (Tahiti and Bora-Bora; 200 km apart) were only
weakly differentiated from each other. Statistical tests demonstrated that the symbiont genetic structure was not correlated
with that of its host, suggesting that dispersal of the symbionts, whether they are transported within a host larva or free
in the water, depends mainly on distance and water currents. In addition, the data suggests that hosts may acquire new symbionts
after maternal transmission, possibly following a disturbance event. Lastly, the weak differentiation between symbiont populations
of P. verrucosa and P. meandrina, both from Moorea, indicated that there was some host-symbiont fine-scale specificity detectable at the genetic resolution
offered by microsatellites. 相似文献
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Hedgerows and hedgerow networks in landscape ecology 总被引:12,自引:0,他引:12
Hedgerows originated and coexist with agriculture. Their internal structure and species diversity vary widely with origin (planted, spontaneous, or remnant), farming practices in adjacent fields, and the refined art of hedgerow management. Most hedgerow species are forest-edge species, and apparently none is limited to hedgerows. Wide hedgerows composed of trees and shrubs appear to function as corridors for movement of many plants and animals across a landscape. The reduction of crop loss, by dampening pest population fluctuations with hedgerow predators, remains a hypothesis for study.Field microclimate downwind of a hedgerow is modified about 16 times the hedgerow height (h) for evaporation, and approximately 28 h for wind speed. A turbulent wind pattern with harsher microclimate is present at 6–8 h if a second hedgerow is nearby downwind. Zones of higher crop productivity at 3- to 6-h downwind, and 2- to 6-h upwind of a second hedgerow may be expected. Overall, we expect little short-term difference in farm-field production with or without hedgerows.Evidence suggests that hedgerow networks, and especially their mesh size (of fields), exert a major control on many major landscape fluxes. Such fluxes include animal populations, wind speed, evapotranspiration and soil desiccation, soil erosion and nutrient runoff, species movement along network lines, and movement of field species across the network. In a relatively short period, the hedgerow ecosystem, with no unique species, has attained a metastable equilibrium, which is regulated by enormous human inputs.More than 20 economic roles of hedgerows are pinpointed. The roles, providing resources and protection of resources, are poorly known quantitatively. We conclude that hedgerows perform diverse functions for society and the farmer that are both economically and ecologically significant. 相似文献
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Several studies have proven the importance of field margins in sustaining biodiversity and other work has been done on the effect of field management on field margin flora. However few models have been built to predict the effects of field management on the flora. Our project addresses this need for a model capable of predicting the effect of cropping techniques and their timing on the flora of field margins. Primula vulgaris is a biodiversity indicator, characteristic of undisturbed flora and found in field margins and woodlands: its population has been declining for several years. We created a temporal matrix model of P. vulgaris populations on field margins, taking into account the effects of field, field margin and roadside management based on literature and expert knowledge. We then analysed its sensitivity to demographic parameters by comparing lambda (growth rate) sensitivity and elasticity. We compared the management parameter effect using the relative growth rate of the population after 6 years of simulation. Sensitivity analysis to biological parameters showed the importance of adult survival and seed production and germination. Results show that P. vulgaris is particularly sensitive to broad-spectrum herbicides and that other management techniques like early mowing, scything and scrub-killer (diluted broad-spectrum herbicide or specific herbicide) are less aggressive. Our simulations show that management of cash crops in Brittany is too aggressive for P. vulgaris populations and that 4-5 years of grassland in the adjacent field are necessary to maintain populations. 相似文献
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A Method for Improving the Management of Controversial Wetland 总被引:3,自引:0,他引:3
Merot P Hubert-Moy L Gascuel-Odoux C Clement B Durand P Baudry J Thenail C 《Environmental management》2006,37(2):258-270
Valley bottom wetlands in agricultural landscapes often are neglected in national and regional wetland inventories. Although
these areas are small, located in the bottomlands of the headwater catchments, and scattered in the rural landscape, they
strongly influence hydrology, water quality, and biodiversity over the whole catchment area. Valley bottom wetlands often
are considered as controversial wetlands. Awareness of the functional role of wetlands is increasing, in parallel with their
progressive disappearance in intensive farming landscapes. The need to improve tools for controlling wetland management is
a primary consideration for decision makers and land users. This article proposes a method for the inventory of valley bottom
wetlands. The method is based on the functional analysis of potential, existing, and efficient valley bottom wetlands (the
PEEW approach). Several indicators are proposed for checking the validity of such an approach. Potential wetlands are delineated
by means of a topographic index using topographic and pedoclimatic criteria computed from a Digital Elevation Model and easily
accessible databases. Existing wetlands are identified from observed surface moisture, the presence of specific wetland vegetation,
or soil feature criteria. Efficient wetlands are defined through a given function, such as flow or pollutant regulation or
biodiversity control. An analysis of areas at the limits between potential, existing, and efficient wetlands highlights land
cultivated or drained in the past, which currently represents negotiating areas in which rehabilitation and other intended
management actions can be implemented. 相似文献
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Nélieu Sylvie Lamy Isabelle Karolak Sara Delarue Ghislaine Crouzet Olivier Barraud Claire Bimbot Maya Allaoui Fatima Hanot Christophe Delorme Arnaud Lévi Yves Hulot Florence D. Baudry Emmanuelle 《Environmental science and pollution research international》2021,28(42):59256-59267
Environmental Science and Pollution Research - Ponds are important for their ecological value and for the ecosystem services they provide to human societies, but they are strongly affected by human... 相似文献
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A Spatially Explicit Resource-Based Approach for Managing Stream Fishes in Riverscapes 总被引:1,自引:0,他引:1
The article describes a riverscape approach based on landscape ecology concepts, which aims at studying the multiscale relationships
between the spatial pattern of stream fish habitat patches and processes depending on fish movements. A review of the literature
shows that few operational methods are available to study this relationship due to multiple methodological and practical challenges
inherent to underwater environments. We illustrated the approach with literature data on a cyprinid species (Barbus barbus) and an actual riverscape of the Seine River, France. We represented the underwater environment of fishes for different discharges
using two-dimensional geographic information system-based maps of the resource habitat patches, defined according to activities
(feeding, resting, and spawning). To quantify spatial patterns at nested levels (resource habitat patch, daily activities
area, subpopulation area), we calculated their composition, configuration, complementation, and connectivity with multiple
spatial analysis methods: patch metrics, moving-window analysis, and least cost modeling. The proximity index allowed us to
evaluate habitat patches of relatively great value, depending on their spatial context, which contributes to the setting of
preservation policies. The methods presented to delimit potential daily activities areas and subpopulation areas showed the
potential gaps in the biological connectivity of the reach. These methods provided some space for action in restoration schemes. 相似文献