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Diet,dietary selectivity and density of South American grey fox,Lycalopex griseus,in Central Chile

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Integrative Zoology 2018年第1期13卷 46-57页

作者： Andrés MUÑOZ-PEDREROS JoséYÁÑEZ Heraldo V.NORAMBUENA Alfredo ZÚÑIGA Nucleus of research in environmental Studies NEA School of Environmental SciencesFaculty of Natural ResourcesCatholic University of TemucoChile center for Agricultural and environmental Studies CEA ValdiviaChile National Museum of natural History SantiagoChile Department of Zoology Faculty of Natural and Oceanic SciencesUniversidad de ConcepciónChile

The South American grey fox Lycalopex griseus is a canid widely distributed in southern South America;however,some aspects of its biology are still poorly *** studied the diet and density of *** in the Lago Peñuelas Biosphere Reserve,in Central *** trophic niche breadth was B=6.16(B_(sta)=0.47)and prey diversity was H′=2.46(H_(max)′=3.17,J′=0.78).The highest proportions of prey consumed in the diet were Oryctolagus cuniculus(52.21%)and other mammals(32.78%).We compared these results with a latitudinal gradient of diet results for this species in *** eats mostly mammals(>90%of total prey),consuming the rodent Phyllotis darwini and reptiles in the northern zone;Oryctolagus cuniculus,Octodon degus and Abrocoma bennetti in the central zone;Abrothrix *** lagomorphs in the southern zone;and Lepus capensis and Ovis aries in the austral *** estimated density of *** in Lago Peñuelas NR was 1.3 foxes/km^(2).

关键词： density Lycalopex griseus Mediterranean-type ecosystem trophic ecology

Changes of marine productivity and sedimentary environment recorded by biogenic components in the Antarctica Ross Sea since the last deglaciation

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Journal of Oceanology and Limnology 2020年第6期38卷 1746-1754页

作者： XIU Chun DU Ming ZHANG Xu HUO Suxia North China Sea environmental Monitoring center of Ministry of natural resources Qingdao 266033China East Sea Marine environmental Investigating and Surveying center of Ministry of natural resources Shanghai 200137China

Changes in the marine productivity and sedimentary environment since the last deglaciation in the Ross Sea are presented in this *** has replaced calcium carbonate as the major biogenic component and has a significantly positive correlation with total organic carbon(TOC),which indicates that siliceous phytoplankton controlled the absorption and release of carbon by the biological pump and was the main producer of marine organic *** the AMS 14C age framework,foraminiferal fossils and redox sensitive elements(RSEs),we found that both the sedimentary environment and marine productivity changed clearly in^11 cal ka BP,which is more likely related with the melting and retreat of the Ross Ice *** addition,the increase of marine productivity promoted the sinking of more organic-matter to the seabed.A large proportion of oxygen in the bottom water body was consumed and more carbon dioxide was produced during the decomposition of organic matter,making the bottom water body more soluble to calcium carbonate.

关键词： biogenic components marine productivity redox environment ice shelf retreat the Ross Sea

Evaluation of Forest Damaged Area and Severity Caused by Ice-snow Frozen Disasters over Southern China with Remote Sensing

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Chinese Geographical Science 2019年第3期29卷 405-416页

作者： WANG Xuecheng YANG Fei GAO Xing WANG Wei ZHA Xinjie Institute of Geographic Sciences and natural resources research Chinese Academy of Sciences State Key Laboratory of Resources and Environmental Information System University of Chinese Academy of Sciences Jiangsu center for Collaborative Innovation in Geographical Information resource Development and Application

The accurate assessment of forest damage is important basis for the forest post-disaster recovery process and ecosystem management. This study evaluates the spatial distribution of damaged forest and its damaged severity caused by ice-snow disaster that occurred in southern China during January 10 to February 2 in 2008. The moderate-resolution imaging spectroradiometer(MODIS)13 Q1 products are used, which include two vegetation indices data of NDVI(Normalized Difference Vegetation Index) and EVI(Enhanced Vegetation Index). Furtherly, after Quality Screening(QS) and Savizky-Golay(S-G) filtering of MODIS 13 Q1 data, four evaluation indices are obtained, which are NDVI with QS(QSNDVI), EVI with QS(QSEVI), NDVI with S-G filtering(SGNDVI) and EVI with S-G filtering(SGEVI). The study provides a new way of firstly determining the threshold for each image pixel for damaged forest evaluation, by computing the pre-disaster reference value and change threshold with vegetation index from remote sensing data. Results show obvious improvement with the new way for forest damage evaluation, evaluation result of forest damage is much close to the field survey data with standard error of only 0.95 and 1/3 less than the result that evaluated from other threshold method. Comparatively, the QSNDVI shows better performance than other three indices on evaluating forest damages. The evaluated result with QSNDVI shows that the severe, moderate, mild damaged rates of Southern China forests are 47.33%, 34.15%, 18.52%, respectively. By analyzing the influence of topographic and meteorological factors on forest-vegetation damage, we found that the precipitation on freezing days has greater impact on forest-vegetation damage, which is regarded as the most important factor. This study could be a scientific and reliable reference for evaluating the forest damages from ice-snow frozen disasters.

关键词： ice-snow disaster vegetation index forest remote sensing southern China

Synergistic effects of particulate matter(PM_10) and SO_2 on human non-small cell lung cancer A549 via ROS-mediated NF-κB activation

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Journal of environmental Sciences 2015年第5期27卷 146-153页

作者： Yang Yun Rui Gao Huifeng Yue Guangke Li Na Zhu Nan Sang College of Environment and resource Research Center of Environment and Health Shanxi University

Since a real atmospheric scenario usually represents a system involving multiple pollutants, air pollution studies typically focused on describing adverse effects associated with exposure to individual pollutants cannot reflect actual health risk. Particulate matter（PM10） and sulfur dioxide（SO2） are two major pollutants derived from coal combustion processes and co-existing in coal-smoke air pollution, but their potentially synergistic toxicity remains elusive thus far. In this study, we investigated the cytotoxic responses of PM10 and SO2, singly and in binary mixtures, using human non-small cell lung cancer A549 cells, followed by clarifying the possible mechanisms for their interaction. The results indicated that the concomitant treatment of PM10 and SO2 at low concentrations led to synergistic injury in terms of cell survival and apoptosis occurrence, while PM10 and SO2 alone at the same concentrations did not cause damage to the cells. Also, radical oxygen species（ROS） production followed by nuclear factor kappa B（NF-κB） activation was involved in the above synergistic cytotoxicity, which was confirmed by the repression of the actions by an ROS inhibitor（NAC）. This implies that assessment of health risk should consider the interactions between ambient PM and gaseous copollutants.

关键词： PM10 SO2 Synergistic toxicity ROS NF-κB

Accurate theoretical evaluation of strain energy of all-carboatomic ring(cyclo[2n]carbon),boron nitride ring,and cyclic polyacetylene

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Chinese Physics B 2022年第12期31卷 357-363页

作者： Tian Lu Zeyu Liu Qinxue Chen Beijing Kein research center for natural Sciences Beijing 100024China School of environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Cyclocarbon fully consists of sp-hybridized carbon atoms,which shows quite unusual electronic and geometric structures compared to common *** this work,we systematically studied strain energy(SE)of cyclocarbons of different sizes using regression analysis method based on electronic energies evaluated at the very accurate DLPNO-CCSD(T)/ccp VTZ theoretical *** addition,ring strain of two systems closely related to cyclocarbon,boron nitride(BN)ring,and cyclic polyacetylene(c-PA),is also *** ideal relationships between SE and number of repeat units(n)are built for cyclo[2n]carbon,B_(n)N_(n),and[2n]c-PA as SE=555.0·n^(-1),145.1·n^(-1),and 629.8·n^(-1)kcal·mol^(-1),respectively,and the underlying reasons of the difference and similarity in their SEs are discussed from electronic structure *** addition,force constant of harmonic potential of C-C-C angles in cyclocarbon is derived based on SE values,the result is found to be 56.23 kcal·mol^(-1)·rad^(-2).The possibility of constructing homodesmotic reactions to calculate SEs of cyclocarbons is also explored in this work,although this method is far less rigorous than the regression analysis method,its result is qualitatively correct and has the advantage of much lower computational *** addition,comparisons show thatωB97XD/def2-TZVP is a good inexpensive alternative to the DLPNO-CCSD(T)/cc-p VTZ for evaluating energies used in deriving SE,while the popular and very cheap B3LYP/6-31G(d)level should be used with caution for systems with global electron conjugation such as c-PA.

关键词： strain energy ring strain cyclocarbon boron nitride ring cyclic polyacetylene quantum chemistry

Particulate matter(PM(2.5)) exposure season-dependently induces neuronal apoptosis and synaptic injuries

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Journal of environmental Sciences 2017年第4期29卷 336-345页

作者： Minjun Chen Ben Li Nan Sang College of Environment and resource Research Center of Environment and HealthShanxi University

Epidemiological studies have shown that particulate matter 2.5（PM（2.5）） not only increases the incidence of cardiopulmonary illnesses but also relates to the development of neurodegenerative diseases. Considering that PM（2.5）is highly heterogeneous with regional disparity and seasonal variation, we investigated whether PM（2.5）exposure induced neuronal apoptosis and synaptic injuries in a season-dependent manner. The results indicated that PM（2.5）altered the expression of apoptosis-related proteins（mainly bax and bcl-2）, activated caspase-3 and caused neuronal apoptosis. Additionally, PM（2.5）decreased the levels of synaptic structural protein postsynaptic density（PSD-95） and synaptic functional protein N-methyl-D-aspartate（NMDA） receptor subunit（NR2B） expression. These effects occurred in a season-dependent manner, and PM（2.5）collected from the winter showed the strongest changes. Furthermore, the effect was coupled with the inhibition of phosphorylated extracellular signal-regulated kinase 1/2（p-ERK1/2） and phosphorylated c AMP-response element binding protein（p-CREB）. Based on the findings, we analyzed the correlations between the chemical composition of PM（2.5）samples and the biological effects, and confirmed that winter PM（2.5）played a major role in causing neuronal apoptosis and synaptic injuries among different season samples.

关键词： Particulate matter(PM(2.5)) Season-dependent effect Neuronal apoptosis Synaptic injury

Impact of exclosures on wood biomass production and fuelwood supply in northern Ethiopia

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Journal of Forestry research 2019年第2期30卷 629-637页

作者： Wolde Mekuria Mastewal Yami Mitiku Haile Kindeya Gebrehiwot Emiru Birhane International Water Management Institute(IWMI) International Institute of Tropical Agriculture(IITA) Department of Land resource Management and environmental Protection Mekelle University Faculty of environmental Sciences and natural resource Management Norwegian University of Life Sciences

In the Ethiopian highlands, communal grazing lands are one of the major land uses, and are source of livelihood for the rural people. Free and uncontrolled grazing in the communal grazing lands is the dominant grazing system. The traditional uncontrolled and free grazing system has caused severe degradation of the grazing lands. As a result, communities have started to establish exclosures and support the restoration of degraded communal grazing lands. Studies have shown that exclosures are effective to restoring degraded communal grazing lands and improving ecosystem services. However, studies that investigate the changes in aboveground biomass following the establishment of exclosures and compare it with fuelwood demand of the beneficiaries in our study area is lacking. Therefore, our study aimed at:(1) quantifying yearly biomass accumulation in exclosures and compare it to fuelwood demand of households that manage the exclosures;(2) assessing household energy sources and their consumption levels. To monitor changes in biomass production with over time, replicated(n = 3) 5 and10 year-old exclosures were sampled. To investigate fuelwood sources and consumption patterns, household surveys, key informant interviews and focus group discussion were conducted. Our results demonstrated that total biomass production increased with exclosure age. In both exclosure, biomass production from Vachellia etbaica was significantly(p \ 0.05) greater than that from ***. Average daily fuelwood consumption per person was(0.63 ± 0.2) kg day^(-1). This means that the total biomass(27.5 Mg year^(-1)) obtained from 114.6 ha of exclosures covers only 9.4% of yearly fuelwood demand of the residents who manage the sampled exclosures. Nearly all respondents(95%) confirmed that they travel more than10 km day^(-1) to gather fuelwood from surrounding degraded forest patches. We recommend plantings of fast growing native tree species within exclosures and around homesteads to provide

关键词： Biomass Ethiopia Exclosures Fuel wood Tigray Woody species

Role of trichome of Pteris vittata *** arsenic hyperaccu-mulation

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Science China(Life Sciences) 2005年第2期48卷 148-154页

作者： LI Wenxue CHEN Tongbin CHEN Yang LEI Mei center for environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

environmental scanning electron microscope(ESEM)fitted with an energy disper-sive X-ray microanalyzer(EDX)was used to investigate the surface micromorphology and arse-nic(As)micro-distribution in Chinese brake(Pteris vittata L.).It was found that amounts of trichome,which possessed multicellular structure with the average length of 160μm and with an average diameter of 28μm,existed in the frond of ***,and the density of trichome on the pinnate axial surface was higher than that on the *** X-ray peak of As was recorded in the epidermal cell and *** relative weight of As in the pinnate trichome,which con-tained the highest concentration of As among all tissues of the plant,was 2.4 and 3.9 times as much as that in the epidermal and mesophyllous cells,*** As concentrations in the basal and stalk cells of the same trichome were higher than that in its cap *** is the first time to report that the trichome of *** plays an important role in arsenic *** finding from the present study implies that much attention should be paid to the role of the trichome in understanding the hyperaccumulation and detoxicity of As in the hyperaccumulator and improving the ability of As accumulation.

关键词： arsenic environmental scanning electron microscope(ESEM) hyperaccumulation micro-distribution Pteris vittata L. trichome.

N-doping offering higher photodegradation performance of dissolved black carbon for organic pollutants: experimental and theoretical studies

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 340-356页

作者： Yong GUO Mengxia CHEN Ting CHEN Ying GUO Zixuan XU Guowei XU Soukthakhane SINSONESACK Keophoungeun KANMANY Key Laboratory of Integrated Regulation and resource Development on Shallow Lakes Ministry of EducationCollege of EnvironmentHohai UniversityNanjing 210093China Key Laboratory of environmental Engineering of Jiangsu Province Jiangsu Provincial Academy of Environmental ScienceNanjing 210036China State Key Laboratory of Pollution Control and resource Reuse Nanjing UniversityNanjing 210023China Central environmental Laboratory Natural Resources and Environment Research InstituteMinistry of Natural Resources and EnvironmentVientiane 999012Laos

We investigated the influence mechanism of N-doping for dissolved black carbon(DBC)photodegradation of organic *** degradation performance of N-doped dissolved black carbon(NDBC)for tetracycline(TC)(71%)is better than that for methylene blue(MB)(28%)under *** levels are both better than DBC degradation performances for TC(68%)and MB(18%)under *** species quenching experiments suggest that h and-O,are the main reactive species for NDBC photodegraded TC,while-OH and h*are the main reactive species for NDBC photodegraded MB.-OH is not observed during DBC photodegradation of *** is likely because N-doping increases valence-band(VB)energy from 1.55 eV in DBC to 2.04 eV in NDBC;the latter is strong enough to oxidize water to ***,N-doping increases the DBC band gap of 2.29 to 2.62 eV in NDBC,resulting in a higher separation efficiency of photo-generated electrons-holes in NDBC than in *** these factors give NDBC stronger photodegradation performance for TC and MB than ***-performance liquid chromatography-mass spectrometry(HPLC-MS)characterization and toxicity evaluation with the quantitative structure-activity relationship(QSAR)method suggest that TC photodegradation intermediates produced by NDBC have less aromatic structure and are less toxic than those produced by *** adopted a theoretical approach to clarify the relationship between the surface groups of NDBC and the photoactive species *** results add to the understanding of the photochemical behavior of NDBC.

关键词： Dissolved black carbon(DBC) N-doping Organic pollutants Band gap Photodegradation