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Madeleine E. Hardus Adriano R. Lameira Steph B.J. Menken Serge A. Wich 《Biological conservation》2012,146(1):177-187
The human footprint is increasing across the world’s natural habitats, causing large negative impacts on the survival of many species. In order to successfully mitigate the negative effects on species’ survival, it is crucial to understand their responses to human-induced changes. This paper examines the effect of one such disturbance, logging, on Sumatran orangutans – a critically endangered great ape. Orangutan population densities may decrease or remain stable after logging, but data on the effects of logging on the behavior of individuals is scant. Here, we provide individual-level behavioral data based on direct observations in 2003–2008 at the Ketambe (Sumatra, Indonesia) research area (partly subject to intense selective logging) in order to assess responses of Sumatran orangutans to logging. Logging significantly negatively affected forest structure and orangutan food resources, specifically important fallback and liana-derived foods. Individual orangutans behaved differently between logged and pristine forest; they moved more and rested less in logged forest. With the exception of figs, diet composition remained overall similar. Altogether, life after logging seems energetically more expensive for orangutans. Based on the results of this study, we provide recommendations for conservation research and guidelines for reduced-impact logging. 相似文献
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Daniel?F.?R.?Clearycleary@naturalis.nnm.nl" title="cleary@science.uva.nl cleary@naturalis.nnm.nl" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Martin?J.?Genner Timothy?J.?B.?Boyle Titiek?Setyawati Celina?D.?Angraeti Steph?B.?J.?Menken 《Landscape Ecology》2005,20(8):989-1001
A comprehensive understanding of variables associated with spatial differences in community composition is essential to explain
and predict biodiversity over landscape scales. In this study, spatial patterns of bird diversity in Central Kalimantan, Indonesia,
were examined and associated with local-scale (habitat structure and heterogeneity) and landscape-scale (logging, slope position
and elevation) environmental variables. Within the study area (c. 196 km2) local habitat structure and heterogeneity varied considerably, largely due to logging. In total 9747 individuals of 177
bird species were recorded. Akaike's information criterion (AIC) revealed that the best explanatory models of bird community
similarity and species richness included both local- and landscape-scale environmental variables. Important local-scale variables
included liana abundance, fern cover, sapling density, tree density, dead wood abundance and tree architecture, while important
landscape-scale variables were elevation, logging and slope position. Geographic distance between sampling sites was not significantly
associated with spatial variation in either species richness or similarity. These results indicate that deterministic environmental
processes, as opposed to dispersal-driven stochastic processes, primarily structure bird assemblages within the spatial scale
of this study and confirm that highly variable local habitat measures can be effective means of predicting landscape-scale
community patterns. 相似文献
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Steph Bennington Will Rayment Rohan Currey Lucy Oldridge Shaun Henderson Marta Guerra Tom Brough David Johnston Chloe Corne David Johnson Liz Slooten Steve Dawson 《水产资源保护:海洋与淡水生态系统》2021,31(3):665-676
- A small population of approximately 68 bottlenose dolphins, Tursiops truncatus, resident in Doubtful Sound, New Zealand, is subject to physiologically challenging conditions, and is exposed to anthropogenic pressure from tourism.
- A voluntary Code of Management incorporating dolphin protection zones (DPZs), in which tour boat access is limited, was established in 2008.
- Kernel density estimation (KDE) was used to quantify dolphin habitat use over a 13-year period in order to describe seasonal variation in habitat use and consistency of habitat use over a decadal period, and to provide quantitative estimates of the extent of overlap between DPZs and core areas (50% volume contour) of habitat use.
- Habitat use varied seasonally, with the inner fjord area used more frequently in warmer months, and with a shift in use to the outer fjord in colder months. Patterns in habitat use were highly consistent over the 13-year duration of the study.
- The spatial overlap between the area of core dolphin habitat and DPZs was low (<18%) overall, and some DPZs were rarely used during colder periods.
- Consistency in habitat use through time vindicates spatial management, but low overlap between core habitat and current DPZs suggests that an expansion of the DPZ areas would confer greater protection.
4.
Martjan Lammertink Dewi M. Prawiradilaga Steph B.J. Menken 《Biological conservation》2009,142(1):166-179
The Great Slaty Woodpecker (Mulleripicus pulverulentus) of South and Southeast Asia, the third largest woodpecker species in the world, is currently in the IUCN Red List category of Least Concern. This woodpecker appears associated with old-growth forests, and the rapid reductions in forest cover and old-growth area in Southeast Asia urged examination of its global population trends. We assessed population densities, tree diameter use by the woodpecker, and logging disturbance at 21 transects in four regions across the range of the species: west Borneo, Lingga Island (Riau Archipelago, Indonesia), Tenasserim (Myanmar), and west-central Myanmar. Transect survey effort was 937 km. We assessed rates of deforestation and loss of old-growth forest in the range of the species from expert review reports. By combining population density and forest cover data sets we calculated the global population trend of the species. We found a preference for large diameter trees by foraging and nesting Great Slaty Woodpeckers, and a reduction of the frequency of such trees in logged forests. Across the four study regions, between old-growth forests and logged forests, densities of Great Slaty Woodpeckers were reduced by 80-94%. Although Great Slaty Woodpeckers occur in 15 countries, ca. 70% of the global population occurs in just four countries (Myanmar, Indonesia, Cambodia, and Malaysia), three of which have high annual rates of deforestation and loss of old-growth forest. Our population calculations show that over the past century at least 90% of the global population of the Great Slaty Woodpecker has been lost. At present 26,000-550,000 individuals remain. The current global decline rate of ca. 59% ± SD 17% in three generations justifies IUCN Vulnerable or Endangered status. Contributing factors to the steep decline rate of the species are a long generation time of 5.9-8.2 years and an association with old-growth, lower elevation forests. The Great Slaty Woodpecker case adds an Asian example to a global pattern of specialized woodpeckers that are associated with old or natural forests. 相似文献
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Kearley GJ Fillaux F Baron MH Bennington S Tomkinson J 《Science (New York, N.Y.)》1994,264(5163):1285-1289
Vibrational spectroscopy with inelastic neutron scattering can provide spectra that are more detailed and easier to interpret than optical spectra. The spectral intensity depends on energy transfer and kinetic momentum transfer, allowing determination of the potential function. Experiments reveal that the proton involved in intermolecular hydrogen bonding in N-methylacetamide and polyglycine I vibrates almost independently. An ionic representation (N(delta-)...H(+)...O(delta-)) of the hydrogen bond is more realistic than the normally accepted covalent model (NH...O). For polyglycine I, the proton experiences a local, symmetric double-minimum potential arising from dynamic exchange between the amide-like (CONH) and imidol-like (HOCN) forms of the peptide unit. 相似文献
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Taylor A Dunne M Bennington S Ansell S Gardner I Norreys P Broome T Findlay D Nelmes R 《Science (New York, N.Y.)》2007,315(5815):1092-1095
We review the potential to develop sources for neutron scattering science and propose that a merger with the rapidly developing field of inertial fusion energy could provide a major step-change in performance. In stark contrast to developments in synchrotron and laser science, the past 40 years have seen only a factor of 10 increase in neutron source brightness. With the advent of thermonuclear ignition in the laboratory, coupled to innovative approaches in how this may be achieved, we calculate that a neutron source three orders of magnitude more powerful than any existing facility can be envisaged on a 20- to 30-year time scale. Such a leap in source power would transform neutron scattering science. 相似文献
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