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11.
Tropical forests across the world provide important habitats for a diverse number of conservation priority species, yet are under threat from a range of anthropogenic impacts including logging. This study aims to quantify mammalian biodiversity in unlogged and logged forests in the adjoining Tembat and Petuang Forest Reserves, Terengganu, on the East Coast of Peninsular Malaysia. Data was collected over a series of surveys using direct and indirect observation methods from 2008 to 2014. A total of 30 medium and large sized mammals species were identified, with 27 of those species found in unlogged forests and 22 species in logged forests. Carnivores encompassed 11 species from 67 observations representing 15% of the total number of observations. The family Felidae had the highest number of species (six species), followed by Hylobatidae, Cercopithecidae and Suidae with three species each. A total of 17 species contributed to more than 90% of the mammal community in the unlogged and logged forests, while six species were uncommon and only observed once during the entire survey. Species abundance in the unlogged forest was significantly greater than the logged forests, but the difference was not significant for species richness. This study provides critical baseline information on the impact of unlogged and logged forests and the identification of threatened species warrant the establishment of conservation measures such as anti-poaching patrol and ranger stations in the study area. 相似文献
12.
G. Ballantyne Katherine C. R. Baldock P. G. Willmer 《Proceedings. Biological sciences / The Royal Society》2015,282(1814)
Interaction networks are widely used as tools to understand plant–pollinator communities, and to examine potential threats to plant diversity and food security if the ecosystem service provided by pollinating animals declines. However, most networks to date are based on recording visits to flowers, rather than recording clearly defined effective pollination events. Here we provide the first networks that explicitly incorporate measures of pollinator effectiveness (PE) from pollen deposition on stigmas per visit, and pollinator importance (PI) as the product of PE and visit frequency. These more informative networks, here produced for a low diversity heathland habitat, reveal that plant–pollinator interactions are more specialized than shown in most previous studies. At the studied site, the specialization index was lower for the visitation network than the PE network, which was in turn lower than for the PI network. Our study shows that collecting PE data is feasible for community-level studies in low diversity communities and that including information about PE can change the structure of interaction networks. This could have important consequences for our understanding of threats to pollination systems. 相似文献
13.
《Mycoscience》2014,55(5):355-360
Coprinopsis asiaticiphlyctidospora (Basidiomycota, Psathyrellaceae), is a new Coprinoid ammonia fungus from Amami and Okinawa, Japan. In macro- and micro-morphology, this species is similar to C. phlyctidospora and C. austrophlyctidospora, but differs in having smaller basidiospores and spiny basidiospore ornamentation. Phylogenetic analysis with the nuclear ribosomal internal transcribed spacer (ITS) data also supports this new taxon. 相似文献
14.
J. B. Wilson 《Oecologia》1987,73(4):579-582
Summary Comparison of co-occurrences between species on a group of islands with those expected from a randombased null model could provide evidence on community structure. However, it is difficult to decide on the appropriate null model. Gilpin and Diamond proposed a model and a test for departure from it, but this test is shown to indicate significant structure even when applied to a matrix of random numbers. An alternative method is suggested, using the distribution of Gilpin and Diamond's deviation as test statistic, but determining the expected distribution by Monto Carlo simulation, and using many such simulations as a randomisation test of significance. The null model used accepts the observed totals of occurrences for islands and species; it therefore offers a somewhat conservative test. Applied to the Vanuatu bird data that Gilpin and Diamond used, significant departure from a null model is seen, but with an excess of extreme negative associations, the opposite result from that given by Gilpin and Diamond's method. It is not possible to tell whether the negative associations are due to autecology, biogeography, or to interactions between species. 相似文献
15.
Parameter estimation techniques for interaction and redistribution models: a predator-prey example 总被引:2,自引:0,他引:2
Summary The use of parameter estimation techniques for partial differential equations is illustrated using a predatorprey model. Whereas ecologists have often estimated parameters in models, they have not previously been able to do so for models that describe interactions in heterogeneous environments. The techniques we describe for partial differential equations will be generally useful for models of interacting species in spatially complex environments and for models that include the movement of organisms. We demonstrate our methods using field data from a ladybird beetle (Coccinella septempunctata) and aphid (Uroleucon nigrotuberculatum) interaction. Our parameter estimation algorithms can be employed to identify models that explain better than 80% of the observed variance in aphid and ladybird densities. Such parameter estimation techniques can bridge the gap between detail-rich experimental studies and abstract mathematical models. By relating the particular bestfit models identified from our experimental data to other information on Coccinella behavior, we conclude that a term describing local taxis of ladybirds towards prey (aphids in this case) is needed in the model. 相似文献
16.
E. N. Kondratieva E. V. Zacharova V. I. Duda V. V. Krivenko 《Archives of microbiology》1989,151(2):117-122
A new anaerobic thermophilic Gram-positive, nonsporeforming bacterium strain ZE-1 was isolated from a hot spring of Kamchatka (USSR). The cells are rod-shaped, (0.5–0.8 · 2.0–20 m), non-motile. The bacterium can grow between 42 and 75°C; the optimal temperature is 65°C. The growth is possible between pH values 5.0 and 8.5; optimal pH is 7.0. The cultures grow on the media containing peptone, yeast extract, or casein hydrolysate as nitrogen sources in the presence of glucose or some other sugars, mannitol or starch. The main fermentation products of glucose are ethanol, acetate, lactate, H2, CO2; byproducts are propionic, butyric and isovaleric acids. Glucose is metabolized via Embden-Meyerhoff-Parnas pathway. Molecular hydrogen does not inhibit growth. The bacterium does not reduce aceton to isopropanol, but is able to form H2S from elemental sulfur. The bacterium contains a soluble hydrogenase. This enzyme catalyzes both evolution and uptake of H2 and is active in the presence of methyl viologen. The DNA-base composition is 34.6 mol%; the genome size 2.08x109 D. The name proposed for the isolated bacterium strain ZE-1 is Thermoanaerobium lactoethylicum spec. nov. 相似文献
17.
The pathway for the aerobic catabolism of 1,3,5-trihydroxybenzene (phloroglucinol) by a new strain of Penicillium was investigated using both in vivo and in vitro cell-free systems. The fungal strain was isolated by enrichment on phloroglucinol and identified as P. simplicissimum (Oud) Thom. It grew optimally at pH 5.5 and 27°C with 119 mM (1.5%w/v) of phloroglucinol in a basal mineral salts medium. Vapours of the crystalline substrate placed in a Petri-plate lid supported the growth of the fungal colonies on the agar surface. Mycelia grown on phloroglucinol accumulated 1,2,4-trihydroxybenzene and resorcinol in the medium. Washed, resting mycelia grown on phloroglucinol, when resuspended in a buffer utilized oxygen in the presence of catechol, resorcinol, pyrogallol and phloroglucinol. A NADPH-dependent reductase in the cell-free extract reduced phloroglucinol to dihydrophloroglucinol. This electron donor could not be replaced by NADH. Resorcinol hydroxylase, phloroglucinol reductase, catechol-1,2-oxygenase, and catechol-2,3-oxygenase were detected in cell-free extracts of mycelia grown on phloroglucinol. The possible steps in the degradation of phloroglucinol are discussed. 相似文献
18.
Limited Tryptic Proteolysis of the Benzodiazepine Binding Proteins in Different Species Reveals Structural Homologies 总被引:2,自引:2,他引:0
Waltraut Friedl Klaus-Ulrich Lentes Elke Schmitz Peter Propping Johannes Hebebrand 《Journal of neurochemistry》1988,51(6):1877-1881
Peptide mapping can be used to elucidate further the structural similarities of the benzodiazepine binding proteins in different vertebrate species. Crude synaptic membrane preparations were photoaffinity-labeled with [3H]flunitrazepam and subsequently degraded with various concentrations of trypsin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by fluorography allowed a comparison of the molecular weights of photolabeled peptides in different species. Tryptic degradation led to a common peptide of 40K in all species investigated, a finding indicating that the benzodiazepine binding proteins are structurally homologous in higher bony fishes and tetrapods. 相似文献
19.
Predator driven changes in community structure 总被引:5,自引:0,他引:5
Summary The zooplankton community of a small pond changed markedly with temporal variation in predation pressure. Long term changes in zooplankton community structure occurred following the replacement of planktivorous fish by phantom midge (Chaoborus americanus) larvae as the predominant predator of zooplankton. The interannual changes following the establishment of Chaoborus included the apparent or near extinction, of species ill adapted to the new predation pressure and the successful colonization of well adapted species. Seasonal changes in the species composition and size distribution of the zooplankton community correlate with temporal variation in predation intensity associated with temperature-activity patterns of the predator or changes in the stage structure of the predator population. 相似文献
20.
Summary According to the equilibrium theory of island biogeography, insularisation will lead to species loss from habitat remnants. Extinctions will continue untill species number equilibrates at a level appropriate for the size and isolation of the island remnants. We tested whether insularisation leads to species loss by comparing plant species numbers on islands of fynbos shrublands surrounded by Afrotemperate evergreen forest with extensive mainland tracts of fynbos. Species area curves for islands and subsamples of mainland had significantly different slopes (z
island=0.43, z
mainland=0.16). Small islands had the fewest species (less than one fifth) relative to mainland samples of similar size. The species area curves intersect at 590 ha so that reserve sizes of this order of magnitude are needed to avoid species losses relative to extensive areas of fynbos.We compared traits of species on islands and mainlands to determine processes most affected by insularisation. Island floras did not differ from the mainland in the mix of dispersal types, pollinator syndromes or proportion of dioecious species. Islands did have significantly fewer species of low stature and significantly more species that survive fire only as seed and not by resprouting. We infer that the main cause of species loss is change in disturbance frequency. Islands have fewer fires and lose species dependent on frequent fires. We predict that island effects could be reduced by judicious fire management of small reserves. 相似文献