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81.
Catalina Munteanu Cornelius Senf Mihai D. Nita Francesco Maria Sabatini Julian Oeser Rupert Seidl Tobias Kuemmerle 《Conservation biology》2022,36(2):e13820
High-conservation-value forests (HCVFs) are critically important for biodiversity and ecosystem service provisioning, but they face many threats. Where systematic HCVF inventories are missing, such as in parts of Eastern Europe, these forests remain largely unacknowledged and therefore often unprotected. We devised a novel, transferable approach for detecting HCVFs based on integrating historical spy satellite images, contemporary remote sensing data (Landsat), and information on current potential anthropogenic pressures (e.g., road infrastructure, population density, demand for fire wood, terrain). We applied the method to the Romanian Carpathians, for which we mapped forest continuity (1955–2019), canopy structural complexity, and anthropogenic pressures. We identified 738,000 ha of HCVF. More than half of this area was identified as susceptible to current anthropogenic pressures and lacked formal protection. By providing a framework for broad-scale HCVF monitoring, our approach facilitates integration of HCVF into forest conservation and management. This is urgently needed to achieve the goals of the European Union's Biodiversity Strategy to maintain valuable forest ecosystems. 相似文献
82.
玉龙县碳减排效应估算主要包括退耕还林、造林、小水电、替代能源(包括沼气池和太阳能)使用等方面. 其中,造林具有较长期的碳汇功能,会持续提供碳增汇服务功能;替代能源的使用可以有效减少薪柴燃烧,在以农村人口为主的玉龙县,薪柴是主要的取暖和生活能源,故替代能源的使用颇具意义. 以2005年为基准年,小水电和替代能源总的碳减排效应为22.24×103 t,其中小水电碳减排效应为14.43 ×103 t,太阳能碳减排效应为66.24 t,沼气池碳减排效应为7.74×103 t;设定了基准年后林木生长过程以及替代能源使用状况的情景,并进行情景模拟,估算了玉龙县造林在5年内会产生碳汇21.07×103 t,10年内会产生碳汇24.92×103 t. 在研究区总的碳减排效应中,小水电、沼气池以及生态林地都有较大贡献,而经济林和草地的贡献相对较小;与5年情景相比,20年情景中小水电和沼气池的贡献有所上升,而生态林地等的贡献相对下降. 相似文献
83.
Climate-related changes that occurred in the Ary-Mas larch forests (the world’s northernmost forest range) in the last three decades of the 20th century have been analyzed. An analysis of remote-sensing images made by Landsat satellites in 1973 and 2000 has provided evidence for an increase in the closeness of larch forest canopy (by 65%) and the expansion of larch to the tundra (for 3–10 m per year) and to areas relatively poorly protected from wind due to topographic features (elevation, azimuth, and slope). It has also been shown that the radial tree increment correlates with summer temperatures (r = 0.65, τ = 0.39) and the amounts of precipitation in summer (r = ?0.51, τ = 0–41) and winter (r = ?0.70, τ = ?0.48), decreases with an increase in the closeness of forest canopy (r = ?0.52, p > 0.8; τ = ?0.48, p > 0.95), and increases with an increase in the depth of soil thawing (r = 0.63, p > 0.9; τ = 0.46, p > 0.9). The density of undergrowth depends on temperatures in winter (τ = 0.53, p > 0.8) and summer (r = 0.98, p > 0.99, τ = 0.9, p > 0.99) and the date of the onset of the growing period (r = ?0.60, p > 0.99; τ = ?0.4, p > 0.99) and negatively correlates with the amount of precipitation in summer (r = ?0.56, p > 0.99, τ = ?0.38, p > 0.99). 相似文献
84.
Parameters characterizing the activity of species in altitudinal zonal elements of the flora have been analyzed in the northern Baikal region. The results provide evidence for the weakening status of xerophilic species in the cenoflora of hemiboreal light coniferous forests of the class Rhytidio-Laricetea, which form the lower part of the forest belt bordering the steppe. This fact indicates that climate on the slopes of mountain ridges is becoming more humid. The increase in humidity may be explained by both progressing degradation of permafrost and increasing precipitation. On the other hand, no significant change has been observed in the cenoflora of mountain taiga forests of the class Vaccinio-Piceetea, which form the upper part of the forest belt. 相似文献
85.
E. Z. Baisheva S. N. Zhigunova V. B. Martynenko P. S. Shirokikh 《Russian Journal of Ecology》2009,40(3):180-186
The composition of bryophytes in forests of the Ufa Plateau has been studied. The results obtained by ordination methods show that the coverage of epigeic mosses decreases with an increase in tree stand density and proportion of broadleaf tree species as well as in the coverage and average height of herbaceous layer. The main factors determining the distribution of epigeic mosses are illumination level, soil fertility, and the degree of soil development. 相似文献
86.
E. J. Sattout P. D. S. Caligari S. N. Talhouk 《Environment, Development and Sustainability》2008,10(1):107-127
The signature and ratification of the convention on biological diversity by the Lebanese government has boosted the declaration of nature reserves. Cedar forests formed the pilot ecosystems, using international funds, for the implementation of a conservation programme and development of management plans. Although different in their attributes, all recent nature reserves have the same basic management objectives and goals but they ignore the idea of taking into account the difference in specific site features and assets that could boost the success of any management plans. Twelve cedar forests flourish in the Mount Lebanon chain. These forests are either protected by the forestry law or are declared as nature reserves by the Ministry of Environment. The results reveal, through Participatory Rural Appraisals and Rapid Rural Appraisals, that religion, geographical location and land ownership play, to a certain extent, a role in adopting successful management practices of cedar forests. The RRAs and PRAs spell out the origins of woodcraft, old stories memorized by elderly people and ethnobotanical knowledge. The 4Rs tools method adopted highlighted the need for more collaboration and synergy of effort between various institutions. The social, ecological and economic aspects of the regions play a major role in defining the backbone of management plans for cedar forests in Lebanon. The present paper proposes guidelines for the establishment of a network of cedar nature reserves in Lebanon adopting collaborative management and assigning a separate role for each reserve; the details rely on the site’s natural features, as well as socio-economic and cultural characteristics. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue 相似文献
87.
I. E. Yamskikh 《Russian Journal of Ecology》2008,39(4):246-253
Fifteen A. baikalensis populations growing in natural and disturbed habitats in the dark-taiga forest belt of the Western Sayan Mountains have been studied with respect to age composition, numbers, and variation and interrelation of vegetative characters and parameters of productivity. Specific features of the effect of gaps in the tree canopy on the state of A. baikalensis cenopopulations have been revealed. 相似文献
88.
Jennifer L. Cochran‐Biederman Katherine E. Wyman William E. French Grace L. Loppnow 《Conservation biology》2015,29(1):175-186
Reintroduction of imperiled native freshwater fish is becoming an increasingly important conservation tool amidst persistent anthropogenic pressures and new threats related to climate change. We summarized trends in native fish reintroductions in the current literature, identified predictors of reintroduction outcome, and devised recommendations for managers attempting future native fish reintroductions. We constructed random forest classifications using data from 260 published case studies of native fish reintroductions to estimate the effectiveness of variables in predicting reintroduction outcome. The outcome of each case was assigned as a success or failure on the basis of the author's perception of the outcome and on whether or not survival, spawning, or recruitment were documented during post‐reintroduction monitoring. Inadequately addressing the initial cause of decline was the best predictor of reintroduction failure. Variables associated with habitat (e.g., water quality, prey availability) were also good predictors of reintroduction outcomes, followed by variables associated with stocking (e.g., genetic diversity of stock source, duration of stocking event). Consideration of these variables by managers during the planning process may increase the likelihood for successful outcomes in future reintroduction attempts of native freshwater fish. Identificación de Correlaciones de Éxito y Fracaso de Reintroducciones de Peces de Nativos Agua Dulce 相似文献
89.
Bytnerowicz A Manning WJ Grosjean D Chmielewski W Dmuchowski W Grodzinska K Godzik B 《Environmental pollution (Barking, Essex : 1987)》1993,80(3):301-305
Ambient concentrations of ozone (O(3)) were measured and O(3) phytotoxicity to tobacco (Nicotiana tabacum L.) was demonstrated in several forest locations in Poland during a pilot study from July-October, 1991. At southern and central locations in Poland, the 24-hour average O(3) concentrations measured with a UV absorption photometer were in the range of 32-55 ppb, and the corresponding 1-hour maxima in the range of 39-83 ppb. At these locations longer period (four to fifteen days) average concentrations were determined using O(3) passive samplers (DGA, Inc.) and were reaching 60 ppb, while at Bialowieza in eastern Poland O(3) concentrations averaged less than 40 ppb. In Szarow, near the Niepolomice Forest in southern Poland, 1-hour O(3) maxima estimated from the data obtained using passive samplers were about 105 ppb in early September. At several locations in southern and central Poland, extensive O(3) injury was determined on O(3)-sensitive Bel W-3 tobacco plants; such injury did not occur in the Bialowieza Forest of eastern Poland. The results of this pilot study indicate that O(3) is present at phytotoxic levels in southern and central Poland. 相似文献
90.
Ecological risk assessment provides a methodology for evaluating the threats to ecosystem function associated with environmental
perturbations or stressors. This report documents the development of a conceptual model for assessing the ecological risk
to the water quality function (WQF) of bottomland hardwood riparian ecosystems (BHRE) in the Tifton-Vidalia upland (TVU) ecoregion
of Georgia. Previus research has demonstrated that mature BHRE are essential to maintaining water quality in this portion
of the coastal plain. The WQF of these ecosystems is considered an assessment endpoit—an ecosystem function or set of functions
that society chooses to value as evidenced by laws, regulations, or common usage. Stressors operate on ecosystems at risk
through an exposure scenario to produce ecological effects that are linked to loss of the desired function or assessment end
point. The WQF of BHRE is at risk because of the ecological and environmental quality effects of a suite of chemical, physical,
and biological stressors. The stressors are related to nonpoint source pollution from adjacent land uses, especially agriculture;
the conversion of BHRE to other land uses; and the encroachment of domestic animals into BHRE. Potential chemical, physical,
and biological stressors to BHRE are identified, and the methodology for evaluating appropriate exposure scenarios is discussed.
Field-scale and watershed-scale measurement end points of most use in assessing the effects of stressors on the WQF are identified
and discussed. The product of this study is a conceptual model of how risks to the WQF of BHRE are produced and how the risk
and associated uncertainties can be quantified. 相似文献