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411.
Gaps and opportunities for the World Heritage Convention to contribute to global wilderness conservation 下载免费PDF全文
James R. Allan Cyril Kormos Tilman Jaeger Oscar Venter Bastian Bertzky Yichuan Shi Brendan Mackey Remco van Merm Elena Osipova James E.M. Watson 《Conservation biology》2018,32(1):116-126
Wilderness areas are ecologically intact landscapes predominantly free of human uses, especially industrial‐scale activities that result in substantial biophysical disturbance. This definition does not exclude land and resource use by local communities who depend on such areas for subsistence and bio‐cultural connections. Wilderness areas are important for biodiversity conservation and sustain key ecological processes and ecosystem services that underpin planetary life‐support systems. Despite these widely recognized benefits and values of wilderness, they are insufficiently protected and are consequently being rapidly eroded. There are increasing calls for multilateral environmental agreements to make a greater and more systematic contribution to wilderness conservation before it is too late. We created a global map of remaining terrestrial wilderness following the established last‐of‐the‐wild method, which identifies the 10% of areas with the lowest human pressure within each of Earth's 62 biogeographic realms and identifies the 10 largest contiguous areas and all contiguous areas >10,000 km2. We used our map to assess wilderness coverage by the World Heritage Convention and to identify gaps in coverage. We then identified large nationally designated protected areas with good wilderness coverage within these gaps. One‐quarter of natural and mixed (i.e., sites of both natural and cultural value) World Heritage Sites (WHS) contained wilderness (total of 545,307 km2), which is approximately 1.8% of the world's wilderness extent. Many WHS had excellent wilderness coverage, for example, the Okavango Delta in Botswana (11,914 km2) and the Central Suriname Nature Reserve (16,029 km2). However, 22 (35%) of the world's terrestrial biorealms had no wilderness representation within WHS. We identified 840 protected areas of >500 km2 that were predominantly wilderness (>50% of their area) and represented 18 of the 22 missing biorealms. These areas offer a starting point for assessing the potential for the designation of new WHSs that could help increase wilderness representation on the World Heritage list. We urge the World Heritage Convention to ensure that the ecological integrity and outstanding universal value of existing WHS with wilderness values are preserved. 相似文献
412.
413.
Inna P. Solyanikova Elena G. Plotnikova Ekaterina S. Shumkova Irina V. Robota Natalya V. Prisyazhnaya 《Journal of environmental science and health. Part. B》2013,48(6):422-431
This work investigated the distribution of the clcF gene in actinobacteria isolated from different ecotopes. The gene encodes chloromuconolactone dehalogenase (CMLD) ClcF, the enzyme found to date in only one representative of Gram‐positive bacteria, Rhodococcus opacus 1CP, adapted to 2‐chlorophenol (2CP). Using primers specific to the clcF gene, from the DNA matrix of rhodococcal strains closely related to species Rhodococcus wratislaviensis (P1, P12, P13, P20, G10, KT112, KT723, BO1) we obtained PCR products whose nucleotide sequences were 100% identical to that of the clcF gene from strain R. opacus 1CP. CMLDs isolated from the biomass of strains Rhodococcus spp. G10 and P1 grown on 2CP did not differ by their subunit molecular mass deduced from the known amino acid sequence of the clcF gene from the ClcF of strain R. opacus 1CP. Matrix‐assisted laser dissociation/ionization time‐of‐flight mass spectrometry showed the presence of a peak with m/z 11,194–11,196 Da both in whole cells and in protein solutions with a ClcF activity. Thus, we have first time shown the distribution of ClcF among actinobacteria isolated from geographically distant habitats. 相似文献
414.
415.
Papis E Bernardini G Gornati R Prati M 《Environmental science and pollution research international》2006,13(4):251-255
- DOI: http://dx.doi.org/10.1065/espr2006.01.014
Background, Aims and Scope Triazole-derivatives are potent antifungal agents used as systemic agricultural fungicides and against fungal diseases in
humans and domestic animals. They act by inhibiting the cytochrome P-450 conversion of lanosterol to ergosterol, thus resulting
in faulty fungal cell wall synthesis. Some data have been published about the teratogenic activity of triazoles on rodent
embryos: Hypoplasias, abnormal shape, agenesis of the branchial arches, for example, were reported as typical induced malformations.
Unfortunately, no data are available on the embryotoxicity of these compounds in amphibians, despite the increasing concern
among the scientific community about the phenomenon of global amphibian population declines. The aim of the present work is
to evaluate the embryo-lethal and teratogenic potentials of Triadimefon (FON), a triazolederivative widely used as an antimycotic
in agriculture, by the test FETAX (Frog Embryos Teratogenic Assay, Xenopus) with particular attention being paid to the analysis
of branchial arch malformations.
Methods Xenopus laevis embryos were exposed continuously from stage 9 to increasing concentrations of FON and analyzed at stage 47
for mortality and teratogenicity (group I) to determine the median lethal (LC50) and teratogenic (TC50) concentrations. Another
two pools of larvae were exposed to FON for a 2 hour period at early gastrula (Group II) or neurula (Group III) stages to
verify which period of development is the most sensitive to FON. The malformations observed were further investigated by histological
section and cartilage staining with Alcian blue.
Results and Discussion The assay has estimated LC50 and TC50 values of 63.8 μM and 2.73 μM, respectively; the resulting TI (Teratogenic Index =
LC50/TC50) value of 23.4 has underlined the very high teratogenic risk associated with this compound. Neurulation was more
sensitive to FON exposure than gastrulation, since the TC50 estimated values for group III (neurula exposed) specimens was
7.6 times lower than those of group II (gastrula exposed). Interestingly, for each group analyzed, 100% of malformed embryos
showed alterations at branchial arch derived cartilages: Anterior cartilages were reduced, missing, fused or incorrectly positioned
while gill cartilages were altered only in the most severely affected specimens. In some cases these malformations were associated
with hyperpigmentation. Our results support the hypothesis that FON can interfere with Neural Crest Cell (NCC) migration,
since craniofacial components and melanophores are derived from neural crest material.
Conclusion In conclusion, our data show Triadimefon to be a potent teratogen able to induce specific craniofacial malformation in Xenopus
laevis embryos, probably interfering with the NCC migration into the branchial mesenchyme. These results are also interesting
for ecotoxicological reasons as FON, as well as other pesticides, are likely to be present in water systems near agricultural
or urban areas which may serve as habitats for developing amphibians and fishes.
Recommendation and Outlook Our results are in agreement with the data obtained on in vitro cultured rat embryos suggesting that the FON mechanism of
action involves strongly conserved molecules. The choice of Xenopus laevis as the model organism allows us to extend the toxicological
and teratological observations to a molecular level, in order to search for novel genes regulated by FON exposure. 相似文献
416.
Optimal strategy in the control of multicomponent biocenoses that are described adequately by an autonomous discrete model has been investigated. It is shown that for any such biocenosis there exists at least one stationary optimal strategy in terms of discounted reward. The optimal strategy is described for communities of competing species, together with the method of its derivation. 相似文献
417.
We explored effects of severe pollution on sexual reproduction of mountain birch, Betula pubescens subsp. czerepanovii, by counting catkins on sample branches and weighing both somatic and generative structures of both short and long shoots from birches growing at 21 sites around large nickel-copper smelter at Monchegorsk, Northwestern Russia. Proportion of reproducing trees, production of catkins, shoot and catkin weight, as well as the relative difference in weight of somatic structures of generative and vegetative shoots, were generally independent of pollution load; in 2003 birches growing in industrial barrens produced more catkins than birches growing in unpolluted forests. Thus, we found no support for the hypothesis that reproductive allocation should decrease with decrease in environmental capacity. Absence of adverse effects might indicate that long-lasting pollution impact already eliminated the most sensitive individuals from the affected birch populations. 相似文献
418.
Claudio Giorlandino M.D. Luisa Mobili Elena Bilancioni Paoloa D'alessio Ornella Carcioppolo Paolo Gentili Antonio Vizzone 《黑龙江环境通报》1994,14(9):803-806
The aim of this study was to compare transplacental with non-transplacental amniocentesis in terms of related complications. Between January 1991 and December 1992, 4564 genetic amniocenteses were performed in 4527 patients (4491 singleton, 35 twin, and one triplet pregnancy) at 15–16 weeks of gestation. All the procedures were ultrasound-guided and performed by the same operator. In 1487 cases, an anterior placenta was traversed with the needle, whereas in 3077 cases, the needle was inserted directly into the amniotic cavity without traversing the placenta. After the exclusion of patients in whom amniotic cell culture failed or in whom an abnormal karyotype was obtained, and of patients lost to follow-up, a total of 4454 patients (98 per cent) were followed for 30 days after amniocentesis. Two spontaneous abortions occurred after a transplacental procedure, and five after a non-transplacental procedure (P = not significant). There were no episodes of amniotic fluid leakage in the first group, whereas 16 ruptures of the membranes that resolved spontaneously occurred in the second group (P<0·01). Our data suggest that transplacental amniocentesis carries a similar abortive risk to and a lower risk of transient rupture of the membranes than non-transplacental amniocentesis and may therefore be preferred at the gestational period examined (15–16 weeks). However, the risk of feto-maternal haemorrhage, which is reported to be higher for a transplacental procedure, must be considered in the case of an anterior placenta. 相似文献
419.
M. Tchebakova Nadezda E. Rehfeldt Gerald I. Parfenova Elena 《Mitigation and Adaptation Strategies for Global Change》2006,11(4):861-882
Inter- and intraspecific effects of climate change were assessed for the dominant conifers of Siberia (60–140∘E and 48–75∘N): Larix spp. (L. sibirica, L. dahurica, and L. sukaczewii) and Pinus sylvestris
. The approach employed a tri-variate (degree-days above 5 ∘C, degree-days below 0 ∘C, and a moisture index) estimate of the climatic envelope within which exists the actual ecological distribution of a species
and their constituent climatypes (genotypes physiologically attuned to similar environments). Limits of the actual ecological
distribution were approximated by reducing the climatic envelope according to effects of permafrost and interspecific competition.
Climatypes were mapped within the climatic envelope according to the climatic interval that must separate populations for
reasonable assurance of genetic differentiation. This interval was calculated from response functions that related 13-year
growth and survival of a species to the difference in climate between the provenance of a climatype and the climate of numerous
test sites distributed across Russia. Mapping species' distributions and their climatypes was done for the contemporary climate
and for future climates predicted by the HadCM3GGa1 scenario of Hadley Centre.
The results showed that if the forests of the future are to reflect the adaptedness of today, the distribution of species
will shift and genotypes within species will be redistributed. Some contemporary climatypes are projected to disappear from
Siberia while others common elsewhere would evolve. To mitigate these effects, climatypes should be transferred today to the
expected future location of their climatic optima, a distance that is likely to approach 700–1200 km for these species. 相似文献
420.
Mikhail Goltsman Elena P. Kruchenkova Sergei Sergeev Paul J. Johnson David W. Macdonald 《Behavioral ecology and sociobiology》2005,59(2):198-206
Since the Pleistocene, Arctic foxes, Alopex lagopus, on Mednyi Island in the North Pacific have been isolated in a small area with rich food resources and no other terrestrial carnivores. This situation provides an unusually simple system within which the effect of food dispersion on demography and social organisation was examined. We studied the composition, location and dispersal of 67 Arctic fox groups and mapped their major food resources (seabird colonies) during 1994–2000 on Mednyi. We compared our observations with the predictions of models of sex-ratio determination. Our observations are most consistent with the predictions of Julliard's (2000) model, where mothers are expected to produce more offspring of the most dispersing sex in low-quality habitats, and more offspring of the most philopatric sex in high-quality habitats. The polygynous foxes on Mednyi Island lived where the principal food resources were patchily distributed (present on 11% of the shoreline), and cub survival to dispersal age or reproductive adult was higher in rich (25/45) than in poor (24/79) home ranges. Furthermore, dispersal was strongly sex-biased: most females (60%) remained on their natal ranges, whereas very few males (9%) did so. Significantly more female than male cubs (54 compared with 24) emerged from dens in resource rich ranges, whereas the sex ratio on poor ranges was approximately equal (51 females and 56 males). While our observations are also to some extent consistent with the local resource enhancement (LRE) hypothesis (which predicts a bias towards the sex most likely to cooperate with parents), this does not account for the observed spatial variability. 相似文献