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161.
Bernardo B. N. Strassburg Agnieszka E. Latawiec Anna Creed Nga Nguyen Gilla Sunnenberg Lera Miles Andrew Lovett Lucas Joppa Ralph Ashton Jörn P. W. Scharlemann Felipe Cronenberger Alvaro Iribarrem 《Sustainability Science》2014,9(2):129-141
There has been a concerted effort by the international scientific community to understand the multiple causes and patterns of land-cover change to support sustainable land management. Here, we examined biophysical suitability, and a novel integrated index of “Economic Pressure on Land” (EPL) to explain land cover in the year 2000, and estimated the likelihood of future land-cover change through 2050, including protected area effectiveness. Biophysical suitability and EPL explained almost half of the global pattern of land cover (R 2 = 0.45), increasing to almost two-thirds in areas where a long-term equilibrium is likely to have been reached (e.g. R 2 = 0.64 in Europe). We identify a high likelihood of future land-cover change in vast areas with relatively lower current and past deforestation (e.g. the Congo Basin). Further, we simulated emissions arising from a “business as usual” and two reducing emissions from deforestation and forest degradation (REDD) scenarios by incorporating data on biomass carbon. As our model incorporates all biome types, it highlights a crucial aspect of the ongoing REDD + debate: if restricted to forests, “cross-biome leakage” would severely reduce REDD + effectiveness for climate change mitigation. If forests were protected from deforestation yet without measures to tackle the drivers of land-cover change, REDD + would only reduce 30 % of total emissions from land-cover change. Fifty-five percent of emissions reductions from forests would be compensated by increased emissions in other biomes. These results suggest that, although REDD + remains a very promising mitigation tool, implementation of complementary measures to reduce land demand is necessary to prevent this leakage. 相似文献
162.
Sexual reproduction of the scyphomedusa Aurelia aurita in relation to temperature and variable food supply 总被引:1,自引:0,他引:1
The effects of food availability and temperature on sexual maturation and female reproductive output of the scyphomedusa
Aurelia aurita was examined in two populations from the contrasting environments of Southampton Water and Horsea Lake, England. Trends in
oogenesis and subsequent reproductive output differed markedly between the two populations. In Southampton Water, the onset
of sexual maturation occurred earliest in the larger medusae, but eventually all females became ripe, the smallest being 45 mm
bell diameter (BD). The decrease in minimum size at maturity was correlated with increasing temperature. In A. aurita from Horsea Lake, size at maturity varied on a seasonal basis, with the smallest ripe female being only 19 to 20 mm BD. There
were spring and autumn periods of sexual maturation in this population. During the autumn period, it is likely that food limitation
was playing a more critical role in determining medusa size, with decreasing temperature indirectly affecting A. aurita by limiting primary and secondary production. In similar-sized ripe medusae, fecundity was greater in Southampton Water,
but the planula larvae produced were significantly smaller than those in Horsea Lake. It is suggested that in Horsea Lake,
the quality of the larvae are greater in terms of biochemical content to ensure survival of the few gametes produced (i.e.
K-strategy). Comparison of the reproductive effort of the two A. aurita populations revealed that medusae from Southampton Water, which experience greater food availability, are able to direct
more energy to reproduction than Horsea Lake medusae. In the latter, A. aurita medusae appear to partition the available food resources into either somatic growth (and therefore increased future fecundity)
when food is abundant, or reproductive growth when food is scarce.
Received: 24 June 1997 / Accepted: 23 March 1998 相似文献
163.
Impact of alternative metrics on estimates of extent of occurrence for extinction risk assessment
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Lucas N. Joppa Stuart H. M. Butchart Michael Hoffmann Steve P. Bachman H. Resit Akçakaya Justin F. Moat Monika Böhm Robert A. Holland Adrian Newton Beth Polidoro Adrian Hughes 《Conservation biology》2016,30(2):362-370
In International Union for Conservation of Nature (IUCN) Red List assessments, extent of occurrence (EOO) is a key measure of extinction risk. However, the way assessors estimate EOO from maps of species’ distributions is inconsistent among assessments of different species and among major taxonomic groups. Assessors often estimate EOO from the area of mapped distribution, but these maps often exclude areas that are not habitat in idiosyncratic ways and are not created at the same spatial resolutions. We assessed the impact on extinction risk categories of applying different methods (minimum convex polygon, alpha hull) for estimating EOO for 21,763 species of mammals, birds, and amphibians. Overall, the percentage of threatened species requiring down listing to a lower category of threat (taking into account other Red List criteria under which they qualified) spanned 11–13% for all species combined (14–15% for mammals, 7–8% for birds, and 12–15% for amphibians). These down listings resulted from larger estimates of EOO and depended on the EOO calculation method. Using birds as an example, we found that 14% of threatened and near threatened species could require down listing based on the minimum convex polygon (MCP) approach, an approach that is now recommended by IUCN. Other metrics (such as alpha hull) had marginally smaller impacts. Our results suggest that uniformly applying the MCP approach may lead to a one‐time down listing of hundreds of species but ultimately ensure consistency across assessments and realign the calculation of EOO with the theoretical basis on which the metric was founded. 相似文献
164.
Ivonne Bedei Tascha Gehrke Karl-Philipp Gloning Matthias Meyer-Wittkopf Daria Willner Martin Krapp Alexander Scharf Jan Degenhardt Kai-Sven Heling Peter Kozlowski Kathrin Trautmann Kai M. Jahns Annegret Geipel Jan-Erik Baumüller Lucas Wilhelm Ingo Gottschalk Andreas Schröer Alexander Graf Aline Wolter Johanna Schenk Axel Weber Ignatia B. Van den Veyver Roland Axt-Fliedner 《黑龙江环境通报》2023,43(2):192-206
Objective
We aimed to investigate how the presence of fetal anomalies and different X chromosome variants influences Cell-free DNA (cfDNA) screening results for monosomy X.Methods
From a multicenter retrospective survey on 673 pregnancies with prenatally suspected or confirmed Turner syndrome, we analyzed the subgroup for which prenatal cfDNA screening and karyotype results were available. A cfDNA screening result was defined as true positive (TP) when confirmatory testing showed 45,X or an X-chromosome variant.Results
We had cfDNA results, karyotype, and phenotype data for 55 pregnancies. cfDNA results were high risk for monosomy X in 48/55, of which 23 were TP and 25 were false positive (FP). 32/48 high-risk cfDNA cases did not show fetal anomalies. Of these, 7 were TP. All were X-chromosome variants. All 16 fetuses with high-risk cfDNA result and ultrasound anomalies were TP. Of fetuses with abnormalities, those with 45,X more often had fetal hydrops/cystic hygroma, whereas those with “variant” karyotypes had different anomalies.Conclusion
Both, 45,X or X-chromosome variants can be detected after a high-risk cfDNA result for monosomy X. When there are fetal anomalies, the result is more likely a TP. In the absence of fetal anomalies, it is most often an FP or X-chromosome variant. 相似文献165.
Fast climate changes in the western Antarctic Peninsula are reducing krill density, which along with increased fishing activities in recent decades, may have had synergistic effects on penguin populations. We tested that assumption by crossing data on fishing activities and Southern Annular Mode (an indicator of climate change in Antarctica) with penguin population data. Increases in fishing catch during the non-breeding period were likely to result in impacts on both chinstrap (Pygoscelis antarcticus) and gentoo (P. papua) populations. Catches and climate change together elevated the probability of negative population growth rates: very high fishing catch on years with warm winters and low sea ice (associated with negative Southern Annular Mode values) implied a decrease in population size in the following year. The current management of krill fishery in the Southern Ocean takes into account an arbitrary and fixed catch limit that does not reflect the variability of the krill population under effects of climate change, therefore affecting penguin populations when the environmental conditions were not favorable.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01386-w) contains supplementary material, which is available to authorized users. 相似文献
166.
Lucas Julie Logeux Valentin Rodrigues Alice M. S. Stien Didier Lebaron Philippe 《Environmental science and pollution research international》2021,28(23):29412-29420
Environmental Science and Pollution Research - UV filters are widely used in many pharmaceutical and personal care products such as sunscreen and cosmetics to protect from UV irradiation. Due to... 相似文献
167.
Excimer laser fragmentation-fluorescence spectroscopy (ELFFS) is shown to be an effective detection strategy for ammonium nitrate and ammonium sulfate particles at atmospheric pressure and room temperature. Following photofragmentation of the ammonium salt particle, fluorescence of the NH fragment is observed at 336 nm. The fluorescence signal is shown to depend linearly on particle surface area for laser intensities varying from 1.2 x 10(8) to 6 x 10(8) W/cm2. The 100 shot (1 s) detection limits for ammonium nitrate range from 20 ppb for 0.2 microm particles to 125 ppb for 0.8 microm particles, where these concentrations are expressed as moles of ammonium ion per mole of air. For ammonium sulfate, the 100 shot (1 s) detection limits vary from 60 ppb for 0.2 microm particles to 500 ppb for 1 microm particles. These detection limits are low enough to measure ammonium salt particles that form in the exhaust of combustion processes utilizing ammonia injection as a nitric oxide control strategy. 相似文献
168.
Roberto Sassi Rosalve Lucas Marcelino Cristiane Francisca Costa 《Environment, Development and Sustainability》2008,10(2):167-178
This paper discusses the misuses of estuaries in Northeast of Brazil and the social contrasts there found. The several kinds
of impacts promoted by capitalist enterprises in one side and by traditional population, who uses estuary areas at another
side, are in complete disagreement with the ethic of sustainable development. Our intention is to demonstrate how these aspects
occur in the River Paraíba do Norte estuary, in the State of Paraíba. Observing the conditions of infrastructure besides the
multiple ways to handle along with the extension of the estuary, we could recognize 59 focus of conflict between the incorrect
use and sustainable mode. Most of the uses concern to traditional artisan fishing, slums and recreational marinas, reflecting
the great social contrast between rich and poor people settled in area studied. Ecological and social implications of these
conflicting uses are discussed and measures to improve the situation are suggested. 相似文献
169.
Camacho Jos A. da Silva Almeida Lucas Rodrguez Mercedes Molina Jess 《Environment, Development and Sustainability》2022,24(4):4602-4622
Environment, Development and Sustainability - In order to adequately assess energy policies and set clear objectives, a key preliminary step is to know the energy use patterns of the different... 相似文献
170.
The aggregate income of oil-exporting countries relative to that of oil-poor countries has been remarkably constant in recent decades, despite the existence of structural gaps in productivity growth rates. This stylized fact is rationalized in an endogenous growth model of asymmetric trade where resource-poor and resource-rich economies display productivity differences but stable income shares due to terms-of-trade dynamics. The model yields two testable predictions that deserve empirical scrutiny: (i) the asymmetric impact, between exporters and importers, of national taxes on resource use on income shares and (ii) the inverse relation between terms-of-trade dynamics and total factor productivity growth. 相似文献