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Damien Denis Jean-Sébastien PierreJoan van Baaren Jacques J.M. van Alphen 《Ecological modelling》2011,222(9):1604-1613
Adult parasitoid females lay their eggs in or on host insects. Most species are incapable of de novo lipogenesis as adults, and lipids accumulated during the larval stage are allocated either to egg production or to adult survival. Lipid consumption increases with distance covered by the parasitoids and thus with the distance between available hosts within a habitat. Temperature should affect parasitoid fitness because it changes the constraint imposed by a limited reserve of lipids and because it influences behaviour. Climate change involves both an increase in average temperature and an increased frequency of extreme weather such as heat waves. We investigated how the predicted increase of temperature will affect parasitoid fitness and how this depends on habitat parameters (spatial distribution of hosts and lipid cost of habitat exploitation). We studied optimal behaviour and calculated fitness at different temperatures and in different habitats using a stochastic dynamic programming model for pro-ovigenic parasitoids (which mature all their eggs before becoming adult). We show that an increase in temperature decreases fitness of parasitoids adapted to lower temperatures. This decrease in fitness depends on habitat quality. In field conditions (assuming small costs of intra-patch foraging), the loss of fitness should be larger in habitats with high inter-patch distance and in habitats with a more aggregated distribution of hosts. The foraging behaviour of parasitoids is also affected; at higher temperature we show that intra-patch foraging becomes less efficient, and patch residence times are longer. 相似文献
85.
Purpose
We reviewed 19 studies of mammals fed with commercialized genetically modified soybean and maize which represent, per trait and plant, more than 80% of all environmental genetically modified organisms (GMOs) cultivated on a large scale, after they were modified to tolerate or produce a pesticide. We have also obtained the raw data of 90-day-long rat tests following court actions or official requests. The data obtained include biochemical blood and urine parameters of mammals eating GMOs with numerous organ weights and histopathology findings.Methods
We have thoroughly reviewed these tests from a statistical and a biological point of view. Some of these tests used controversial protocols which are discussed and statistically significant results that were considered as not being biologically meaningful by regulatory authorities, thus raising the question of their interpretations.Results
Several convergent data appear to indicate liver and kidney problems as end points of GMO diet effects in the above-mentioned experiments. This was confirmed by our meta-analysis of all the in vivo studies published, which revealed that the kidneys were particularly affected, concentrating 43.5% of all disrupted parameters in males, whereas the liver was more specifically disrupted in females (30.8% of all disrupted parameters).Conclusions
The 90-day-long tests are insufficient to evaluate chronic toxicity, and the signs highlighted in the kidneys and livers could be the onset of chronic diseases. However, no minimal length for the tests is yet obligatory for any of the GMOs cultivated on a large scale, and this is socially unacceptable in terms of consumer health protection. We are suggesting that the studies should be improved and prolonged, as well as being made compulsory, and that the sexual hormones should be assessed too, and moreover, reproductive and multigenerational studies ought to be conducted too. 相似文献86.
Mauro Tretiach Fabio Candotto Carniel Stefano Loppi Alberto Carniel Adriano Bortolussi Denis Mazzilis Clorinda Del Bianco 《Environmental monitoring and assessment》2011,175(1-4):589-600
A lichen transplant study aimed at investigating a strong increase in mercury concentrations in lichens was run in a territory of NE Italy where background values were very low only 8 years before. Thalli of the lichen Pseudevernia furfuracea collected in a pristine area were exposed for 1.5, 3 and 6 months at 31 sites selected according to the observed pattern of Hg concentrations, location of the suspected source (a new waste incinerator) and prevailing wind direction. Hg strongly increased at eight sites after 1.5 months, at 12 after 3 months and at 20 after 6 months. The highest values were always located SW and S of the incinerator, in good agreement with the prevailing night wind direction. It was concluded that, although the immediate risk for the population living close to the incinerator is low, long-term hazard due to Hg accumulation in the surrounding environment should be seriously taken into account. 相似文献
87.
Melilotus Thyssen Beatriz Beker Dilek Ediger Doruk Yilmaz Nicole Garcia Michel Denis 《Environmental monitoring and assessment》2011,172(1-4):1-16
Present study was conducted in rapidly growing city Islamabad, and surface soils were collected from three major land cover types viz., built-up, drain side, and green areas. A total of seven physicochemical parameters and 11 metals were determined in surface soils. Factor analysis based on principal component analysis explained total variance of 68.0%, 64.5%, and 60.2% of three land cover types and showed high loadings for major elements (Mg and K) in built-up and green area and Fe in drain side. Top soil pollution index was carried out by using geo-accumulation index and metal pollution index (MPI6). Concentration of major elements (Ca, Mg, Na, K) in surface soils is derived by parent material, whereas concentration of Fe, Ni, Pb, and Zn were mainly related with anthropogenic sources. Geostatistical methods such as kirging identified hotspot areas of metal contamination by Pb, Ni, and Zn in built-up areas influenced mainly by vehicular emissions and waste disposal. The results stresses that land clearing should be avoided to reduce contamination and management of urban soils. 相似文献
88.
Conservation Prioritization Using GAP Data 总被引:7,自引:0,他引:7
A. Ross Kiester J. Michael Scott Blair Csuti Reed F. Noss Bart Butterfield Kevin Sahr Denis White 《Conservation biology》1996,10(5):1332-1342
Data collected by the Gap Analysis Program in the state of Idaho (U.S.A.) are used to prioritize the selection of locations for conservation action and research. Set coverage and integer programming algorithms provide a sequence of localities that maximize the number of species or vegetation classes represented at each step. Richness maps of vegetation cover class diversity, terrestrial vertebrate species diversity ("hot spot analysis"), endangered, threatened, and candidate species diversity, and unprotected vertebrate species diversity ("gap analysis"), when prioritized, show a rapid accumulation of species as more localities are chosen for terrestrial vertebrates and unprotected vertebrates. Gap analysis identifies four target areas ("gaps") that include 79 of the 83 vertebrate species not currently protected. Accumulation of vegetation cover classes and endangered, threatened, and candidate species is much slower. Sweep analysis is used to determine how well prioritizing on one component of diversity accumulates other components. Endangered, threatened, and candidate species do not sweep total vertebrates as well as unprotected vertebrates do, but are better than vegetation classes. Total vertebrates sweep endangered, threatened, and candidate species better than unprotected vertebrates do, which in turn are better than vegetation classes. We emphasize that prioritization must be part of conservation efforts at multiple scales and that prioritization points out important localities where more detailed work mast be undertaken. 相似文献
89.
Summary The sources of dark smoke and particulate elemental carbon (PEC) in the London and United Kingdom atmospheres have been estimated from emission inventories. Diesels are responsible for about 60 percent of the dark smoke and 95 percent of the PEC in London, and about 30 percent of the dark smoke and 90 percent of the PEC in the UK. The role of PEC in the soiling of materials is considered. An experimental programme in the Hatfield Tunnel revealed a soiling rate constant of 1.9 yr–1. The socio-economic implications of building soiling are considered.Dr Trudie Mansfield completed her postgraduate training at Middlesex Polytechnic, where her research supervisor, Dr Ron Hamilton, and Bryan Ellis are members of staff in the Urban Pollution Research Centre (address, Bounds Green Road, London N11 2NQ) and Peter Newby is a staff member in the School of Geography (address, Queensway, Enfield EN3 4SF). Trudie Mansfield is a Senior Scientific Officer in the Air Quality Division of the Department of the Environment. 相似文献
90.
The impact of climate change on tourism in Germany,the UK and Ireland: a simulation study 总被引:3,自引:0,他引:3
We downscale the results of a global tourism simulation model at a national resolution to a regional resolution. We use this
to investigate the impact of climate change on the regions of Germany, Ireland and the UK. Because of climate change, tourists
from all three countries would spend more holidays in the home country. In all three countries, climate change would first
reduce the number of international arrivals—as Western European international tourist demand falls—but later increase numbers—as
tourism demand from increasingly rich tropical countries grows. In Ireland and the UK, the regional pattern of demand shifts
is similar to the international one: tourism shifts north. In Germany, the opposite pattern is observed as the continental
interior warms faster than the coast: tourism shifts south.
相似文献
Jacqueline M. HamiltonEmail: |