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131.
Understanding the distribution and composition of soil microbes in bare patches is a critical step to improving ecological remediation. The effects of different vegetative restoration types on soil microbes within semi‐arid bare patches remain unclear. Here, we evaluated the distribution of soil fungi and bacteria among different ecological restoration types at the southern Taihang Mountains. Analysis of variance showed that the chemical properties of soil with vegetation cover have higher nutrient quality than those of the exposed soil. The results also suggested that vegetative restoration significantly improved the diversity and the richness of the soil fungal and bacterial communities. Sequencing results showed that Ascomycota and Basidiomycota were the main soil fungal communities, whereas Proteobacteria, Acidobacteria, and Actinobacteria were the main soil bacterial communities. There were significant relationships between the contents of moisture, organic matter and organic carbon and the soil fungal/bacterial communities. Venn and network diagrams indicated that the vegetative restoration types largely influenced the soil fungi and weakly influenced the soil bacteria in the bare patches. This study discusses the importance of vegetative restoration in the ecological remediation of bare patches. These findings provide effective references for soil restorative measures, water conservation, and bare‐spot reduction at the southern Taihang Mountains in future.  相似文献   
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Seasonal records of nymphs of the water strider Aquarius paludum Fabricius (Heteroptera: Gerridae) at a waterway in Kochi prefecture, Japan (33°00′N to 33°30′N), in 2007, show that populations of new generation adults occur four or more times during the year, in mid and late May; late July to early August; September; and October to November. In laboratory experiments, more than 50% of adults are reproductive, irrespective of photoperiod, and this ratio increases to 80% even under a short‐day LD 11.5 : 13.5 h photocycle, which corresponds to the winter season at Kochi (33°N). There is a diminishing photoperiodic response in relation to the induction of diapause compared with measurements made in previous years (1995–1997), suggesting that reproduction may be possible over a much longer period in the near future (and even in winter) if local climate warming is sustained. A high proportion of males sampled in 2008 have small testes and a high proportion of females do not have mature oöcytes even in summer. This contrasts with earlier data showing that the testis volume index for the same period is greater in 1995–1997, and that 75% of females have mature oöcytes. These changes suggest that the Kochi‐Nankoku population of A. paludum is beginning to show partial aestivation. Overwintering adults of both sexes are found to have no mature flight muscles in October/November 2008. This is in marked contrast with earlier data from 1995 and 2004. Adults that are reared in the laboratory also show a lower flight propensity in response to shorter day lengths. The absence of mature flight muscles in the autumn and lower flight propensity under shorter days may indicate a cessation of dispersal between the summer habitats and overwintering sites on land far from the waterways. Taken together, these data suggest that populations of A. paludum in the Kochi‐Nankoku region are continuing to show adaptive changes, apparently in relation to global warming.  相似文献   
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Aim A common strategy for conserving biodiversity in fire‐prone environments is to maintain a diversity of post‐fire age classes at the landscape scale, under the assumption that ‘pyrodiversity begets biodiversity’. Another strategy is to maintain extensive areas of a particular seral state regarded as vital for the persistence of threatened species, under the assumption that this will also cater for the habitat needs of other species. We investigated the likely effects of these strategies on bird assemblages in tree mallee vegetation, characterized by multi‐stemmed Eucalyptus species, where both strategies are currently employed. Location The semi‐arid Murray Mallee region of south‐eastern Australia. Methods We systematically surveyed birds in 26 landscapes (each 4‐km diameter), selected to represent gradients in the diversity of fire age classes and the proportion of older vegetation (> 35 years since fire). Additional variables were measured to represent underlying vegetation‐ or fire‐mediated properties of the landscape, as well as its biogeographic context. We used an information‐theoretic approach to investigate the relationships between these predictor variables and the species richness of birds (total species, threatened species and rare species). Results Species richness of birds was not strongly associated with fire‐mediated heterogeneity. Species richness was associated with increasing amounts of older vegetation in landscapes, but not with the proportion of recently burned vegetation in landscapes. Main conclusions The preference of many mallee birds for older vegetation highlights the risk of a blanket application of the ‘pyrodiversity begets biodiversity’ paradigm. If application of this paradigm involved converting large areas from long unburned to recently burned vegetation to increase fire‐mediated heterogeneity in tree mallee landscapes, our findings suggest that this could threaten birds. This research highlights the value of adopting a landscape‐scale perspective when evaluating the utility of fire‐management strategies intended to benefit biodiversity.  相似文献   
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Smart photovoltaic windows (SPWs) are functional devices possessing the capabilities of electrical power output, energy saving, and privacy protection by managing sunlight under external stimuli and potentially applicable in the fields of energy‐saving buildings, automobiles, and switchable optoelectronics. However, long response time, low power conversion efficiency (PCE), poor stability and cycling performance, and monostimuli responsive behavior restrict their practical applications. To address these issues, high‐efficiency and reliable SPWs are demonstrated by coupling multiresponsive liquid crystal/polymer composite (LCPC) films and semi‐transparent perovskite solar cells (ST‐PSCs). In this design, fast and multiple stimuli‐responsive LCPC films are utilized as an inside layer to control the transparency of SPWs. The ST‐PSCs with competitive PCE and qualified transparency acting as an outside layer offer energy generation functionality. Benefiting from repeatable transparency transition modulated by external stimuli, a series of working modes are achieved in the SPWs providing distinguished and stable energy generation, energy saving, and privacy protection performances.  相似文献   
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Higher biomass especially of some aquatic macrophyte species offered a higher density of phytophilous zoobenthos, but did not increase the proportion of non‐planktonic to planktonic prey in young‐of‐the‐year perch Perca fluviatilis. Both abundance and biomass of non‐planktonic prey dominated over planktonic prey in the pond with lower biomass of aquatic macrophytes and lower food. Survival of P. fluviatilis was lower (20%) in the pond with lower food than in the other pond (34%), however, specific growth rate (1·3% day?1) and final Fulton's condition factor of P. fluviatilis were similar in both ponds.  相似文献   
139.
Semi‐aquatic mammals have secondarily returned to the aquatic environment, although they spend a major part of their life operating in air. Moving both on land, as well as in, and under water is challenging because such species are considered to be imperfectly adapted to both environments. We deployed accelerometers combined with a depth sensor to study the diving behavior of 12 free‐living Eurasian beavers Castor fiber in southeast Norway between 2009 and 2011 to examine the extent to which beavers conformed with mass‐dependent dive capacities, expecting them to be poorer than wholly aquatic species. Dives were generally shallow (<1 m) and of short duration (<30 s), suggesting that the majority of dives were aerobic. Dive parameters such as maximum diving depth, dive duration, and bottom phase duration were related to the effort during different dive phases and the maximum depth reached. During the descent, mean vectorial dynamic body acceleration (VeDBA—a proxy for movement power) was highest near the surface, probably due to increased upthrust linked to fur‐ and lung‐associated air. Inconsistently though, mean VeDBA underwater was highest during the ascent when this air would be expected to help drive the animals back to the surface. Higher movement costs during ascents may arise from transporting materials up, the air bubbling out of the fur, and/or the animals’ exhaling during the bottom phase of the dive. In a manner similar to other homeotherms, beavers extended both dive and bottom phase durations with diving depth. Deeper dives tended to have a longer bottom phase, although its duration was shortened with increased VeDBA during the bottom phase. Water temperature did not affect diving behavior. Overall, the beavers’ dive profile (depth, duration) was similar to other semi‐aquatic freshwater divers. However, beavers dived for only 2.8% of their active time, presumably because they do not rely on diving for food acquisition.  相似文献   
140.
Failure of perennial species to regenerate is a significant threat to semi‐arid woodlands across south‐eastern Australia. High grazing pressure eliminates the recruitment of many perennial species in semi‐arid woodlands, but little is known about requirements for regeneration under low grazing pressure. We tested the effects of addition of water (irrigation to match the largest rainfall events of the last century), seed, soil disturbance and fire within a grazing exclosure in Belah (Casuarina pauper) woodland in the Murray‐Sunset National Park, Victoria. Recruitment was observed in 13 perennial species and was dominated by chenopods. Addition of water, seed and soil disturbance increased abundance of juvenile perennial species above the low‐level background recruitment that occurred in the prevailing drought conditions. This supports the view that continuous recruitment occurs for many semi‐arid perennials. Low seed availability and an inability to maintain soil moisture conditions matching that of regeneration events are likely factors in the lack of recruitment for tree species and limited response of shrubs in this experiment.  相似文献   
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