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1.
Karen F. Gaines James M. Novak Christopher W. Bobryk Susan A. Blas 《Environmental monitoring and assessment》2014,186(4):2067-2079
The U.S. Department of Energy's (USDOE) Savannah River Site (SRS) is a former nuclear weapon material production and current research facility adjacent to the Savannah River in South Carolina, USA. The purpose of this study was to determine the background radiocesium (137Cs) body burden (e.g., from global fallout) for white-tailed deer (Odocoileus virginianus) inhabiting the SRS. To differentiate what the background burden is for the SRS versus 137Cs obtained from SRS nuclear activities, data were analyzed spatially, temporally and compared to other off-site hunting areas near the SRS. The specific objectives of this study were: to compare SRS and offsite deer herds based on time and space; to interpret comparisons based on how data were collected as well as the effect of environmental and anthropogenic influences; to determine what the ecological half-life/decay rate is for 137Cs in the SRS deer herd; and to give a recommendation to what should be considered the background 137Cs level in the SRS deer herd. Based on the available information and analyses, it is recommended that the determination of what is considered background for the SRS deer herd be derived from data collected from the SRS deer herd itself and not offsite collections for a variety of reasons. Offsite data show extreme variability most likely due to environmental factors such as soil type and land-use patterns (e.g., forest, agriculture, residential activities). This can be seen from results where samples from offsite military bases (Fort Jackson and Fort Stewart) without anthropogenic 137Cs sources were much higher than both the SRS and a nearby (Sandhills) study site. Moreover, deer from private hunting grounds have the potential to be baited with corn, thus artificially lowering their 137Cs body burdens compared to other free-ranging deer. Additionally, sample size for offsite collections were not robust enough to calculate a temporal decay curve with an upper confidence level to determine if the herds are following predicted radioactive decay rates like the SRS or if the variability is due to those points described above. Using mean yearly values, the ecological half-life for 137Cs body burdens for SRS white-tailed deer was determined to be 28.79 years—very close to the 30.2 years physical half-life. 相似文献
2.
Tahamina Khanam Abul Rahman Blas Mola-Yudego Jouni Pykäläinen 《Mitigation and Adaptation Strategies for Global Change》2017,22(3):469-483
Forests play a fundamental role in the global carbon cycle and can be managed to mitigate greenhouse gas emissions and conserve or sequester carbon. Global policy and environmental changes can affect regional consumption of forest products, as well as inter-regional trade of forest goods and services. This study analyzes global and regional change impacts on the production, consumption and trade of forest products in two Nordic countries, Finland and Sweden. Annual data on removal and trade (1964–2012) for roundwood and sawnwood is used to identify structural breaks based on Chow tests. According to the analysis, the time period is divided into two periods: t1 (1964–1980) and t2 (1981–2012). In the first period, breaks occurred in 1975 and 1976 in the Finnish model and no break is found in the Swedish model. In the second period, we identify breaks in 1991 and 1992 for the Finnish model and in 2004, 2005 and 2006 for the Swedish model. Although our findings have broad empirical support, we do not identify any specific incident as a direct cause of the changes in the consumption and trade patterns of the two types of wood in these countries. The models and analysis presented here can serve as methodological tools for policymakers to better understand the effects of structural changes in the production of forest goods and services in the Nordic region and globally. 相似文献
3.
Elie Gaget Diego Pavón-Jordán Alison Johnston Aleksi Lehikoinen Wesley M. Hochachka Brett K. Sandercock Alaaeldin Soultan Hichem Azafzaf Nadjiba Bendjedda Taulant Bino Luka Božič Preben Clausen Mohamed Dakki Koen Devos Cristi Domsa Vitor Encarnação Kiraz Erciyas-Yavuz Sándor Faragó Teresa Frost Clemence Gaudard Lívia Gosztonyi Fredrik Haas Menno Hornman Tom Langendoen Christina Ieronymidou Vasiliy A. Kostyushin Lesley J. Lewis Svein-Håkon Lorentsen Leho Luigujõe Włodzimierz Meissner Tibor Mikuska Blas Molina Zuzana Musilová Viktor Natykanets Jean-Yves Paquet Nicky Petkov Danae Portolou Jozef Ridzoň Samir Sayoud Marko Šćiban Laimonas Sniauksta Antra Stīpniece Nicolas Strebel Norbert Teufelbauer Goran Topić Danka Uzunova Andrej Vizi Johannes Wahl Marco Zenatello Jon E. Brommer 《Conservation biology》2021,35(3):834-845
Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species. An evaluation of the relative importance of colonization-extirpation processes is important to inform conservation strategies that aim for both climate debt reduction and species conservation. We assessed the colonization-extirpation dynamics involved in community changes in response to climate inside and outside PAs. To do so, we used 25 years of occurrence data of nonbreeding waterbirds in the western Palearctic (97 species, 7071 sites, 39 countries, 1993–2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate species turnover induced by temperature increase. We determined whether thermal community adjustment was associated with colonization by warm-dwelling species or extirpation of cold-dwelling species by modeling change in standard deviation of the CTI (CTISD). Using linear mixed-effects models, we investigated whether communities in PAs had lower climatic debt and different patterns of community change than communities outside PAs. For CTI and CTISD combined, communities inside PAs had more species, higher colonization, lower extirpation, and lower climatic debt (16%) than communities outside PAs. Thus, our results suggest that PAs facilitate 2 independent processes that shape community dynamics and maintain biodiversity. The community adjustment was, however, not sufficiently fast to keep pace with the large temperature increases in the central and northeastern western Palearctic. Our results underline the potential of combining CTI and CTISD metrics to improve understanding of the colonization-extirpation patterns driven by climate warming. 相似文献
4.
Tahamina Khanam Jukka Matero Blas Mola-Yudego Lauri Sikanen Abul Rahman 《Mitigation and Adaptation Strategies for Global Change》2016,21(3):445-460
The aim of this study is to develop a theoretical model by which to demonstrate how taxes and subsidies work as external factors to substitute fossil fuel by a forest-based biofuel. For biofuels, this study predominantly considers solid-form biomass that generates electricity; for fossil fuels, it considers coal. The model results explicated with three states by using various numeric values taken from the literature. Three states are as follows: a situation without a tax and subsidy, a situation with a biofuel subsidy, and a situation with a biofuel subsidy and a fossil fuel tax. The results of the first state exemplify current fuel market situation; those of the second indicate that the aggregate demand for biofuel has shifted upwards by around 15 % and that substitution has increased by around 18 % due to biofuel subsidies being offered. Under the third state, aggregate biofuel demand has shifted upwards by around 19 %, reduced the demand for fossil fuels by around 13 %, and increased substitution by around 31 %. This state relates to a greater sense of social welfare than other two states. It is conceivable that the joint application of taxes and subsidies will succour biofuel to supplant fossil fuel in the near future. 相似文献
5.
Celia A Harvey Arnulfo Medina Dalia Merlo Sánchez Sergio Vílchez Blas Hernández Joel C Saenz Jean Michel Maes Fernando Casanoves Fergus L Sinclair 《Ecological applications》2006,16(5):1986-1999
As tropical regions are converted to agriculture, conservation of biodiversity will depend not only on the maintenance of protected forest areas, but also on the scope for conservation within the agricultural matrix in which they are embedded. Tree cover typically retained in agricultural landscapes in the neotropics may provide resources and habitats for animals, but little is known about the extent to which it contributes to conservation of animal species. Here, we explore the animal diversity associated with different forms of tree cover for birds, bats, butterflies, and dung beetles in a pastoral landscape in Nicaragua. We measured species richness and abundance of these four animal taxa in riparian and secondary forest, forest fallows, live fences, and pastures with high and low tree cover. We recorded over 20,000 individuals of 189 species including 14 endangered bird species. Mean abundance and species richness of birds and bats, but not dung beetles or butterflies, were significantly different among forms of tree cover. Species richness of bats and birds was positively correlated with tree species richness. While the greatest numbers of bird species were associated with riparian and secondary forest, forest fallows, and pastures with >15% tree cover, the greatest numbers of bat species were found in live fences and riparian forest. Species assemblages of all animal taxa were different among tree cover types, so that maintaining a diversity of forms of tree cover led to conservation of more animal species in the landscape as a whole. Overall, the findings indicate that retaining tree cover within agricultural landscapes can help conserve animal diversity, but that conservation efforts need to target forms of tree cover that conserve the taxa that are of interest locally. Preventing the degradation of remaining forest fragments is a priority, but encouraging farmers to maintain tree cover in pastures and along boundaries may also make an important contribution to animal conservation. 相似文献
6.
Khanam Tahamina Rahman Abul Mola-Yudego Blas Pykäläinen Jouni 《Mitigation and Adaptation Strategies for Global Change》2020,25(4):733-734
Mitigation and Adaptation Strategies for Global Change - This paper was published on March 2017, Volume 22, Issue 3, 469–483pp, titled “Identification of structural breaks in the forest... 相似文献
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8.
Jacquelyn L. Gill Jessica L. Blois Blas Benito Solomon Dobrowski Malcolm L. Hunter Jr. Jenny L. McGuire 《Conservation biology》2015,29(3):640-648
Climate change will require novel conservation strategies. One such tactic is a coarse‐filter approach that focuses on conserving nature's stage (CNS) rather than the actors (individual species). However, there is a temporal mismatch between the long‐term goals of conservation and the short‐term nature of most ecological studies, which leaves many assumptions untested. Paleoecology provides a valuable perspective on coarse‐filter strategies by marshaling the natural experiments of the past to contextualize extinction risk due to the emerging impacts of climate change and anthropogenic threats. We reviewed examples from the paleoecological record that highlight the strengths, opportunities, and caveats of a CNS approach. We focused on the near‐time geological past of the Quaternary, during which species were subjected to widespread changes in climate and concomitant changes in the physical environment in general. Species experienced a range of individualistic responses to these changes, including community turnover and novel associations, extinction and speciation, range shifts, changes in local richness and evenness, and both equilibrium and disequilibrium responses. Due to the dynamic nature of species responses to Quaternary climate change, a coarse‐filter strategy may be appropriate for many taxa because it can accommodate dynamic processes. However, conservationists should also consider that the persistence of landforms varies across space and time, which could have potential long‐term consequences for geodiversity and thus biodiversity. 相似文献
9.
Peñas J Benito B Lorite J Ballesteros M Cañadas EM Martinez-Ortega M 《Environmental management》2011,48(1):168-176
Habitat fragmentation due to human activities is one of the most important causes of biodiversity loss. In Mediterranean areas
the species have co-evolved with traditional farming, which has recently been replaced for more severe and aggressive practices.
We use a methodological approach that enables the evaluation of the impact that agriculture and land use changes have for
the conservation of sensitive species. As model species, we selected Linaria nigricans, a critically endangered plant from arid and semiarid ecosystems in south-eastern Spain. A chronosequence of the evolution
of the suitable habitat for the species over more than 50 years has been reconstructed and several geometrical fragmentation
indices have been calculated. A new index called fragmentation cadence (FC) is proposed to quantify the historical evolution
of habitat fragmentation regardless of the habitat size. The application of this index has provided objective forecasting
of the changes of each remnant population of L. nigricans. The results indicate that greenhouses and construction activities (mainly for tourist purposes) exert a strong impact on
the populations of this endangered species. The habitat depletion showed peaks that constitute the destruction of 85% of the
initial area in only 20 years for some populations of L. nigricans. According to the forecast established by the model, a rapid extinction could take place and some populations may disappear
as early as the year 2030. Fragmentation-cadence analysis can help identify population units of primary concern for its conservation,
by means of the adoption of improved management and regulatory measures. 相似文献
10.
Xu Xiaoqian Mola-Yudego Blas Selkimäki Mari Zhang Xiaoning Qu Mei 《Environmental science and pollution research international》2023,30(4):9011-9021
Environmental Science and Pollution Research - The treatment of agricultural waste plays an important role in the sustainability of agricultural production and the well-being of rural communities.... 相似文献