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91.
Effects of Habitat Fragmentation on Bird Species in a Relict Temperate Forest in Semiarid Chile 总被引:4,自引:0,他引:4
Abstract: We analyzed the structure and composition of a bird assemblage in a fragmented relict temperate forest located in northcentral Chile ( Fray Jorge National Park). In terms of species composition, the bird assemblage we found in Fray Jorge was more similar to southern temperate forest sites, located more than 1200 km south of Fray Jorge, than to localities found in nearby scrub habitats. The relict character and long-term isolation of the Fray Jorge forest provides a natural experiment with which to establish the potential long-term effects of fragmentation and isolation on southern Chilean temperate forests. Between May 1996 and March 1997, we conducted seasonal surveys of birds in six forest fragments, ranging in size from 0.5 to 22.5 ha, at Fray Jorge. The number of bird species at each forest fragment was positively correlated with fragment area during all seasons. The relict forest system had a steeper species-area slope than that reported for similar temperate-forest bird assemblages in forest fragments within Chiloé Island and for islands across the Chiloé Archipelago in southern Chile. In this regard, this bird fauna resembled a depauperate oceanic archipelago. This difference in area effects is likely a consequence of the minimization of rescue effects because of the absence of large source forest areas nearby and the long-term isolation of the system. In addition, the distribution of species among forest fragments in Fray Jorge was not random, showing a nested subset pattern. Thus, some species occur across all fragments, regardless of their area, and therefore are less affected by habitat fragmentation and less prone to local extinction. These results suggest that, for south-temperate forest birds, large fragments (or reserves) should afford better protection against extinction than small forest patches. 相似文献
92.
Policy documents are commonly identified as key outcomes that guide initiatives directed by senior university leaders towards sustainability through plans and policies. Many studies have called for a more integration of sustainability into universities. Nevertheless, the interest in sustainability issues has been more recent in the specific case of Spain. This study analyses the strategic plans developed by Spanish universities in the last decade with two different aims: first, we examine the extent to which Spanish universities are incorporating strategies on sustainability. The second goal evaluates whether the presence of strategies on sustainability in Spanish universities could be associated with coercive and mimetic pressures. Findings indicate the low presence of strategies on sustainability in Spanish universities. Moreover, the results seem to suggest that the presence of strategies on sustainability in Spanish universities could be linked with coercive and mimetic pressures emanating from the State performance funding for universities. The results indicate that universities usually incorporate practices and strategies on sustainability as a response of the pressure exerted by institutional forces, such as the funding systems of higher education institutions. 相似文献
93.
94.
David A. Ross Héctor M. Guzmán Vincent J. Van Hinsberg Catherine Potvin 《Journal of environmental science and health. Part. B》2016,51(10):675-687
Concentrations of eight elements were measured in Chelonia mydas and Lepidochelys olivacea eggs collected along the Pacific coast of Panama. Manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), and mercury (Hg) concentrations were similar to previous reports of these species from around the world, while lead (Pb) was lower than previous reports. Cd posed the highest health risk to people who regularly eat the eggs, with average consumption rates leading to target hazard quotients (THQ) of up to 0.35 ± 0.15. Our conclusions indicate that current turtle egg consumption in isolated, coastal Pacific communities may pose a health concern for young children, and that youth and young adults should limit their consumption of turtle eggs to reduce their total intake of nonessential metals. 相似文献
95.
Sánchez-Arcilla Agustín Sierra Joan Pau Brown Sally Casas-Prat Mercè Nicholls Robert James Lionello Piero Conte Dario 《Regional Environmental Change》2016,16(8):2471-2484
Regional Environmental Change - The potential impact of climate change on port operations and infrastructures has received much less attention than the corresponding impact for beach systems.... 相似文献
96.
Bilgili Levent Çetinkaya Afşın Yusuf 《Journal of Material Cycles and Waste Management》2023,25(1):324-336
Journal of Material Cycles and Waste Management - In this study, an average waste composition was determined using the Provincial Environmental Status Reports of 81 provinces in Turkey for 2019,... 相似文献
97.
Cebeci Havva Hande Açıkalın Korkut Figen Aysel Kantürk 《Journal of Material Cycles and Waste Management》2023,25(4):2205-2221
Journal of Material Cycles and Waste Management - The current study aimed to determine the characteristics and kinetic parameters for the pyrolysis of printed circuit board (PCB) wastes including... 相似文献
98.
Cristina E. Almeida-Naranjo Bryan Morillo María B. Aldás Nicole Garcés Alexis Debut Victor H. Guerrero 《补救:环境净化治理成本、技术与工艺杂志》2023,33(2):135-150
The removal of heavy metals from wastewater has become a global challenge, which demands the continuous study of efficient and low-cost treatment alternatives such as adsorption. In this research, the removal of zinc was evaluated using batch adsorption processes with nonconventional materials such as graphene oxide (GO), magnetite (MG), and their composites (GO:MG), formulated with three weight ratios (2:1, 1:1, and 1:2). Graphene was synthesized by the modified Marcano method, using pencil lead graphite as a precursor. MG and the composites were synthesized by chemical coprecipitation of ferrous sulfate and ferric chloride. The materials were characterized by Raman and Fourier transform infrared spectroscopies, scanning electron microscopy, X-ray diffraction, and the Brunauer–Emmett–Teller method to determine the functional groups, microstructural and morphological characteristics, and specific surface area. Batch adsorption tests were carried out to optimize the adsorbent dose and contact time with zinc solutions of 10 ppm. Zinc adsorption reached equilibrium at 2 h, with an optimal dose between 0.25 and 1.0 g/L. The maximum zinc removal efficiencies/adsorption capacities were 98.6%/165.6, 83.4%/47.6, 83.5%/21.9, 72.8%/19.9, and 82.2%/9.25 mg/g using GO, 2GO:1MG, 1GO:1MG, 1GO:2MG, and MG, respectively. Furthermore, the analysis of the isotherm and adsorption kinetics models determined that the adsorption processes using MG and the composites fit the Sips and pseudo-second-order models. 相似文献
99.
García-Nieto PJ 《Journal of environmental management》2006,79(4):372-382
This paper studies the scavenging efficiencies of aerosol emissions from coal-fired power plants under different removal mechanisms (coagulation, heterogeneous nucleation and gravitational settling) as a function of time. It also analyses the ‘health impact’ of the aerosol before and after the above dynamic mechanisms by comparing the respirable dust fractions. The well-known equations of evolution are applied to an average PSD that represents the exhaust particulate emissions from coal-fired power plants (i.e. Aboño power plant in Asturias that belongs to Hidrocantábrico Group, S.A.). From this study it is inferred that respirable dust is scavenged with the greatest difficulty and when compared with the initial volume of respirable dust, roughly 20% remains after 18 h of gravitational settling. Therefore, gravitational settling is the main removal mechanism of respirable dust compared to condensation and coagulation. 相似文献
100.
BR-319: Brazil’s Manaus-Porto Velho Highway and the Potential Impact of Linking the Arc of Deforestation to Central Amazonia 总被引:3,自引:0,他引:3
Brazil’s BR-319 Highway linked Manaus, in the state of Amazonas, to Porto Velho, Rondônia, until it became impassable in 1988. Now it is proposed for reconstruction and paving, which would facilitate migration from the “Arc of Deforestation” in the southern part of the Amazon region to new frontiers farther north. The purpose of the highway, which is to facilitate transport to São Paulo of products from factories in the Manaus Free Trade Zone, would be better served by sending the containers by ship to the port of Santos. The lack of a land connection to Manaus currently represents a significant barrier to migration to central and northern Amazonia. Discourse regarding the highway systematically overestimates the highway’s benefits and underestimates its impacts. A variety of changes would be needed prior to paving the highway if these potential impacts are to be attenuated. These include zoning, reserve creation, and increased governance in various forms, including deforestation licensing and control programs. More fundamental changes are also needed, especially the abandonment of the long-standing tradition in Brazil of granting squatters’ rights to those who invade public land. Organizing Amazonian occupation in such a way that road construction and improvement cease to lead to explosive and uncontrolled deforestation should be a prerequisite for approval of the BR-319 and other road projects for which major impacts are expected. These projects could provide the impetus that is needed to achieve the transition away from appropriation of public land by both small squatters and by grileiros (large-scale illegal claimants). A delay in reconstructing the highway is advisable until appropriate changes can be effected. 相似文献