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Liu X.,State Key Joint Laboratory of Environment Simulation and Pollution Control | Liu X.,Tsinghua University | Wu P.,China Agricultural University | Songer M.,Smithsonian Conservation Biology Institute | And 4 more authors.
Ecological Indicators | Year: 2013

Ecological indicators or indices have been widely used to simplify and measure complex ecosystems. It is critical to identify suitable indicators or indices to improve monitoring and understanding of complex natural systems. Camera trapping is an objective technique that can provide a large amount of information on wildlife. The purpose of our study is to explore the effective ecological indices for wildlife diversity analysis and monitoring in Guanyinshan Nature Reserve of Shaanxi Province, China. Since July 2009, a total of 18 cameras were installed in the reserve from August 2009 to July 2011, collecting 2115 photo captures during these 24 months. We developed five abundance indices, including relative abundance index (RAI), monthly relative abundance index (MRAI), time-period relative abundance index (TRAI), night-time relative abundance index (NRAI) and species abundance index (N) to integrate the information derived from captures. Results are: (1) 27 species were detected and 6 species had high RAI values of over 79.3%, including takin (Budorcas taxicolor), common goral (Naemorhedus goral), tufted deer (Elaphodus cephalophus), golden pheasant (Chrysolophus pictus), wild boar (Sus scrofa), and mainland serow (Capricornis sumatraensis). (2) MRAI shows a consistent monthly activity pattern of all animals being active in June and July and inactive in February. (3) TRAIs of the most abundant six species show that takin, tufted deer and common goral have the similar daily activity pattern with one peak at dawn and one peak at dusk. The daily activity patterns of golden pheasant and wild boar show that they are most active during the day time, with wild boar being particularly active at noon. NRAIs of mainland serow show the highest nocturnality and of golden pheasant the lowest nocturnality. (4) We estimated abundance of takin, tufted deer and wild boar by using our developed index. The abundance for the three species shows an increasing trend during the 2-year study period, particularly for wild boar. Our results provided an interesting comparison of species diversity and their activity patterns. As trapping continues we will have a consistent source of monitoring data to evaluate changes in species abundance and activities. Therefore, the conclusion is that the methods we used and the indices we developed are capable to estimate species activity patterns and abundance dynamics which are useful for future wildlife management in Guanyinshan Nature Reserve and elsewhere. © 2012 Elsevier Ltd. All rights reserved.

Sun Q.-N.,Tsinghua University | Li J.-F.,Tsinghua University | Wang J.-L.,Tsinghua University | Wang J.-L.,State Key Joint Laboratory of Environment Simulation and Pollution Control
Yuanzineng Kexue Jishu/Atomic Energy Science and Technology | Year: 2010

The advances in cement chemistry and the new cement products, the application of admixtures, additives and fibers can contribute to the formulation study of radioactive wastes cementation. The application status of cement matrices for immobilization of radioactive wastes, including Portland cement, alkali-activated slag cement, calcium sulfoaluminate cement etc. was reviewed. The admixtures, additives and fibers used for improving cemented wastes performance, including wastes loading, compressive strength and long-term durability of cemented wastes were introduced. The objective of this review is to provide some new thoughts for the research and development of radioactive wastes cementation.

Liu X.-H.,State Key Joint Laboratory of Environment Simulation and Pollution Control | Liu X.-H.,Tsinghua University | Wu Y.,Tsinghua University | Wu Y.,Nanjing Institute of Environmental Sciences
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2012

Large-area flowering of the giant pandas' staple food is an important factor which can influence their survival. Therefore, it is necessary to predict the bamboo flowering. Foping Nature Reserve was taken as the study area. The research selected the giant pandas' staple-food bamboos Bashania fargesii, Fargesia qinlingensis and Fargesia dracocephala with different flowering situations (i. e., flowering, potential flowering, non-flowering with far distance) to measure the spectral reflectance of bamboo leaves. We studied the influence of bamboo flowering on the spectral features of three bamboo species through analyzing the original spectral reflectance and their red edge parameters. The results showed that (1) the flowering changed the spectra features of bamboo species. The spectral reflectance of B. fargesii shows a pattern: flowering bamboonon-flowering bamboo with far distance. Among three bamboo species, F. dracocephala showed the greatest change, and then F. qinlingensis. (2) After bamboo flowering, the red edge of B. fargesii has no obvious shifting, while the other two bamboos have distinctive shifting towards the shorter waves. The study found that the original spectral feature and the red edge all changed under various flowering states, which can be used to provide the experimental basis and theoretic support for the future prediction of bamboo flowering through remote sensing.

Liu X.-H.,State Key Joint Laboratory of Environment Simulation and Pollution Control | Liu X.-H.,Tsinghua University | Wu Y.,Tsinghua University | Wu Y.,Nanjing Institute of Environmental Sciences
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2013

The present research aims at utilizing hyperspectra information to estimate the content of endogenous hormones for predicting the bamboo flowering. The authors selected the giant panda's staple-food bamboos Bashania fargesii, Fargesia qinlingensis and Fargesia dracocephala in different flowering situations to measure their hyperspectral reflectance in Foping Nature Reserve. The enzyme-linked immunosorbent assay was used to measure the contents of four endogenous hormones: Gibberellin (GA3), Auxin (IAA), Zeatin nucleotide (Zr) and Abscisic acid (ABA), and non-parametric test was applied to analyze their differences. Then, we built the responding relationship models between hormones and hyperspectral reflectance. The results showed that (1) GA3 contents of B. fargesii and F. dracocephala were higher in the flowering bamboo than in the non-flowering bamboo, while F. qinlingensis showed the opposite result; IAA and ABA contents of three bamboos were all lower in non-flowering bamboo than in the flowering one; Zr contents for three bamboo species were higher in the non-flowering bamboo than in the flowering one. (2) Except that B. fargesii's IAA and Zr had significant relationships with original spectral reflectance among some bands, other hormones of bamboos all showed the poor relationships with the original spectra; however, some specific bands of all four hormones of three bamboos had the very significant relationships with the first derivative reflectance. (3) The precisions of linear models were higher than the Parabola models. The authors concluded that the close relationships between the hormones' contents and spectra reflectance can be used to forecast the flowering of panda bamboos.

Chen L.,CAS Beijing National Laboratory for Molecular | Chen L.,Tsinghua University | Li J.,Tsinghua University | Li J.,State Key Joint Laboratory of Environment Simulation and Pollution Control | Ge M.,CAS Beijing National Laboratory for Molecular
Chemical Engineering Journal | Year: 2011

The nano TiO2 supported V2O5-WO3/TiO2 catalysts (VWTi) were prepared by impregnation method assisted with ultrasonic energy. Their poisoning on activity by alkali metals (Na, K, Ca and Mg) was investigated. The degree of the poisoning effect for all the alkali metal doped catalysts was shown as follows: K>Na>Ca>Mg. Further investigations were carried by NH3-TPD, DRIFTS, XPS and H2-TPR characterization. Na and K could decrease the amount and stability of the Brönsted acid sites to a greater extent than Mg and Ca. Surface chemisorbed oxygen could also be reduced and the downward trend was in good agreement with SCR activity. In addition, the reducibility of vanadium species on the Ca and Mg doped catalysts are higher than that on the Na and K doped catalysts with the same alkali metal oxides loadings. Furthermore, Na and K ions could also affect the reduction degree of tungsten species, while no obvious changes have happened for the tungsten species over Ca- and Mg-VWTi catalysts. Consequently, the different poisoning effects of these four alkali metals doped nano V2O5-WO3/TiO2 catalysts are correlated not only to the surface acidity but also to the reducibility of vanadium and tungsten species. © 2010 Elsevier B.V.

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