Pure SnO 2 and SnO 2 polycrystalline nanofibers doped with multiwall carbon nanotubes ͑MWCNTs͒ are synthesized by electrospinning followed by calcination in air at 500°C. The measurement results by sensors fabricated from these fiber mats at steady state show that the n-type SnO 2 /MWCNT nanofibers are able to detect carbon monoxide at 50 ppm at room temperature, while the pure SnO 2 nanofibers are insensitive up to 500 ppm. The MWCNT doped SnO 2 nanofibers have demonstrated their potentials for wearable room temperature gas sensors with low cost and power consumption.

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BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

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Many artificial wetland constructions are currently underway worldwide to compensate for the degradation of natural wetland systems. Researchers face the responsibility of proposing wetland management and species protection strategies to ensure that constructed wetlands positively impact waterbird diversity. Nestedness is a commonly occurring pattern for biotas in fragmented habitats with important implications for conservation; however, only a few studies have focused on seasonal waterbird communities in current artificial wetlands. In this study, we used the nestedness theory for analyzing the annual and seasonal community structures of waterbirds in artificial wetlands at Lake Dianchi (China) to suggest artificial wetland management and waterbird conservation strategies. We carried out three waterbird surveys per month for one year to observe the annual, spring, summer, autumn, and winter waterbird assemblages in 27 lakeside artificial wetland fragments. We used the NeD program to quantify nestedness patterns of waterbirds at the annual and seasonal levels. We also determined Spearman partial correlations to examine the associations of nestedness rank and habitat variables to explore the factors underlying nestedness patterns. We found that annual and all four seasonal waterbird compositions were nested, and selective extinction and habitat nestedness were the main factors governing nestedness. Further, selective colonization was the key driver of nestedness in autumn and winter waterbirds. We suggest that the area of wetland fragments should be as large as possible and that habitat heterogeneity should be maximized to fulfill the conservation needs of different seasonal waterbirds. Furthermore, we suggest that future studies should focus on the least area criterion and that vegetation management of artificial wetland construction should be based on the notion of sustainable development for humans and wildlife.

Nature reserves (NRs) have been the backbone of biodiversity conservation and the construction of China’s ‘ecological-civilization’ since the 1950s. With over 11,800 protected areas (PAs) covering 18% of the country’s land area, Chinese NRs have made a great contribution to global biodiversity conservation. At this point, better protection effectiveness can be achieved by optimizing the management organization rather than expanding the area. We analyzed the management structure of Chinese NRs by looking at their ranks, the hierarchy of administrative organs, number of grass-root stations, manpower, and financial resources, among other variables. We found that the average number of staff employed and yearly financial input per km2 of Chinese NRs were both higher than the world and US averages. However, the range was extremely high, revealing great unbalance among different regions and ranks of NRs. In particular, the western part of China, which is less developed and features the least disturbed ecosystems, received less funding and staff resources than the developed east. A further analysis of the highest-ranked nature reserves, i.e., the national nature reserves (NNRs), showed that administrative organs of different hierarchical statuses (the lowest being Deputy family, the highest being Division level) could be in charge of them. Unexpectedly, we found that the amount of human and financial resources injected into NNRs was correlated with the level of their administration but dissociated from other important factors such as the reserve’s size or ecological value. Furthermore, the management organization was inadequate, with many NRs lacking key departments as defined by Chinese nature reserve regulations. We suggest that the administrative levels of management organization in NRs should be unified, and through the existing ecological transfer payments policy, strengthen the financial and staffing input in the western NRs of China. Moreover, the internal structure of NRs management should include all relevant departments with specific tasks and the creation of grass-root stations should be promoted without neglecting the capacity building to improve staff’s knowledge.

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