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101.
Tropical rainforests are subject to extensive degradation by commercial selective logging. Despite pervasive changes to forest structure, selectively logged forests represent vital refugia for global biodiversity. The ability of these forests to buffer temperature‐sensitive species from climate warming will be an important determinant of their future conservation value, although this topic remains largely unexplored. Thermal buffering potential is broadly determined by: (i) the difference between the “macroclimate” (climate at a local scale, m to ha) and the “microclimate” (climate at a fine‐scale, mm to m, that is distinct from the macroclimate); (ii) thermal stability of microclimates (e.g. variation in daily temperatures); and (iii) the availability of microclimates to organisms. We compared these metrics in undisturbed primary forest and intensively logged forest on Borneo, using thermal images to capture cool microclimates on the surface of the forest floor, and information from dataloggers placed inside deadwood, tree holes and leaf litter. Although major differences in forest structure remained 9–12 years after repeated selective logging, we found that logging activity had very little effect on thermal buffering, in terms of macroclimate and microclimate temperatures, and the overall availability of microclimates. For 1°C warming in the macroclimate, temperature inside deadwood, tree holes and leaf litter warmed slightly more in primary forest than in logged forest, but the effect amounted to <0.1°C difference between forest types. We therefore conclude that selectively logged forests are similar to primary forests in their potential for thermal buffering, and subsequent ability to retain temperature‐sensitive species under climate change. Selectively logged forests can play a crucial role in the long‐term maintenance of global biodiversity.  相似文献   
102.
Drying of garlic slices in thin-layer have been studied with Infrared (IR) at 0.075, 0.15, 0.225 and 0.3 W cm?2 radiation intensity and 0.75 and 1.25 m s?1 air flow velocity. The results showed increasing in drying rate and decreasing at the time of drying with decreasing air flow velocity and increasing IR radiation intensity. The effective moisture diffusivity (Deff) was obtained using Fick’s diffusion equation and its mean values ranged between 5.83×10?11 and 7.66×10?10 m2 s?1 for all investigated conditions. In addition, a third-order polynomial equation linking the effective moisture diffusivity and moisture content was found. Average activation energy increased with the decrease of IR radiation and increase of air flow velocity. Thirteen different mathematical models were verified with non-linear regression analysis for describing the garlic drying process. Modified Henderson and Pabis model presented the best prediction of the drying of garlic slices.  相似文献   
103.
Observations on habitat and behavior are reported for 10 of the 12 known species of the genus Hoplolatilus. These small (6 to 20 cm total length) fishes are widespread in the tropical Indo-Pacific and Red Sea. Adults live as stable monogamous pairs and each pair shares a burrow. They feed on plankton during the day and retreat into a burrow to escape disturbances and to retire for the night. Usually the burrow location is inconspicuous, but 3 of the deeper water species build elaborate rubble mounds, to over 3 m in diameter, around their burrows. We studied the shallowest (13 to 61 m depth) species, H. starcki, that does not build mounds, and compared it with the shallowest (51 to 73+ m) mound builder H. fronticinctus. Over 60 pairs of H. starcki were studied. Ten-min observations (N=237) on 14 pairs were analyzed by time of day for feeding rates, courtship behavior, and distances of pairs in relation to each other and their burrows. Over 20 pairs of H. fronticinctus were studied by divers and on video from a remotely operated vehicle. These data showed a high rate of moving rubble (96.0 h-1), an activity almost absent in non-mound builders (0.1 h-1). Observations are also reported for non-mound builders H. chlupatyi, H. cuniculus, H. luteus, H. marcosi, H. oreni, H. purpureus, H. sp. (an undescribed species), and the mound builder H. pohle. The results of a survey of 159 dive sites with suitable habitats to over 25 m depth (including 49 dive sites over 50 m) indicate an abundance of Hoplolatilus species in the southwest Pacific. In comparison, 41 survey dive sites (including 20 over 50 m) in the Red Sea resulted in an unexplained absence of Hoplolatilus species except in deep water (>60 m). Mound builder, H. geo, is known in the north Red Sea (depths 80-116 m). H. fronticinctus, newly reported here, was found in the south Red Sea (depths 70-73 m). We also report, for the first time, live sightings of the rare H. oreni and H. sp. living unpaired and without mounds below 60 m in the south Red Sea. The wide distribution of H. fronticinctus, like the related Malacanthus brevirostris, suggests a possible advantage to building mounds even though mounds reveal the location of burrows. Recent techniques to extend scuba depths should increase our knowledge of the distribution of Hoplolatilus species.  相似文献   
104.
Redox and CO photolysis FTIR spectra of yeast cytochrome c oxidase WT and mutants are compared to those from bovine and P. denitrificans CcOs in order to establish common functional features. All display changes that can be assigned to their E242 (bovine numbering) equivalent and to weakly H-bonded water molecules. The additional redox-sensitive band reported at 1736?cm?1 in bovine CcO and previously assigned to D51 is absent from yeast CcO and couldn't be restored by introduction of a D residue at the equivalent position of the yeast protein. Redox spectra of yeast CcO also show much smaller changes in the amide I region, which may relate to structural differences in the region around D51 and the subunit I/II interface.  相似文献   
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Adult sex ratio and fecundity (juveniles per female) are key population parameters in sustainable wildlife management, but inferring these requires abundance estimates of at least three age/sex classes of the population (male and female adults and juveniles). Prior to harvest, we used an array of 36 wildlife camera traps during 2 and 3 weeks in the early autumn of 2016 and 2017, respectively. We recorded white‐tailed deer adult males, adult females, and fawns from the pictures. Simultaneously, we collected fecal DNA (fDNA) from 92 20 m × 20 m plots placed in 23 clusters of four plots between the camera traps. We identified individuals from fDNA samples with microsatellite markers and estimated the total sex ratio and population density using spatial capture–recapture (SCR). The fDNA‐SCR analysis concluded equal sex ratio in the first year and female bias in the second year, and no difference in space use between sexes (fawns and adults combined). Camera information was analyzed in a spatial capture (SC) framework assuming an informative prior for animals’ space use, either (a) as estimated by fDNA‐SCR (same for all age/sex classes), (b) as assumed from the literature (space use of adult males larger than adult females and fawns), or (c) by inferring adult male space use from individually identified males from the camera pictures. These various SC approaches produced plausible inferences on fecundity, but also inferred total density to be lower than the estimate provided by fDNA‐SCR in one of the study years. SC approaches where adult male and female were allowed to differ in their space use suggested the population had a female‐biased adult sex ratio. In conclusion, SC approaches allowed estimating the preharvest population parameters of interest and provided conservative density estimates.  相似文献   
110.
Ecological release is often attributed to the rapid adaptive diversification of phenotypic traits. However, it is not well understood how natural selection changes its strength and direction through the process of ecological release. Herein, we demonstrated how shell colour of the Japanese land snail Euhadra peliomphala simodae has diversified via a shift in natural selection due to ecological release after migration from the mainland to an island. This snail''s shell colour diversified on the island due to disruptive selection after migration from the mainland. We used trail camera traps to identify the cause of natural selection on both the mainland and the island. We then conducted a mark–recapture experiment while collecting microhabitat use data. In total, we captured and marked around 1,700 snails on the mainland, some of which were preyed upon by an unknown predator. The trail camera traps showed that the predator is the large Japanese field mouse Apodemus speciosus, and the predatory frequency was higher on the mainland than on the island. However, this predation did not correlate with shell colour. Microhabitat use on the island was more extensive than on the mainland, with snails on the island using both ground and arboreal microhabitats. A Bayesian estimation showed that the stabilizing selection on shell colour came from factors other than predation. Our results suggest that the course of natural selection was modified due to ecological release after migration from the mainland, explaining one cause of the phenotypic diversification.  相似文献   
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