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Decadal (2003–2013) changes in liana diversity,abundance and aboveground biomass in four inland tropical dry evergreen forest sites of peninsular India

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Journal of Forestry Research 2016年第1期27卷 133-146页

作者： Elumalai Pandian Narayanaswamy Parthasarathy department of Ecology & environmental sciences School of Life Sciences Pondicherry University

In 2013, we re-inventoried all lianas （≥1 cm diameter measured at 1.3 m from the rooting point） in four I-ha permanent plots distributed one each in four sites of inland tropical dry evergreen forest on the Coromandel Coast （Pudukottai district） of peninsular India, established in 2003. Among the four sites, Shanmuganathapuram （SP） and Araiyapatti （AP） were much disturbed and the other two sites （Karisakkadu--KR and Maramadakki--MM） were moderately disturbed. We inventoried a total of 3425 lianas representing 37 species of 33 genera and 22 families. Over a decade （2003-2013） liana species richness increased at two sites （MM and SP） and no changes occurred at the other two sites. Liana abundance increased by 210, 211,164 and 162 individuals at sites AP, KR, MM and SP, respectively, and basal area increased （from 1.09 to 1.76 m2 at AP, 0.67 to 0.86 m2 at KR, 1.68 to 2.06 mz at MM, and from 0.44 to 1.06 m2 at SP）. Over a 10-year period, three species （Abrus precatorius, Canavalia virosa, and Cocculus hirsutus） were lost and five species （Gloriosa superba, Ampelocissus tomentosa, Capparis sepiaria, Aganosma cymosa and Tiliacora acuminata） were newly added. Total aboveground biomass increased by 18.5, 0.74, 3.6 and 9.5 Mg ha-1, respectively, at sites AP, KR, MM and SP.

关键词： Tropical dry evergreen forest Lianaabundance Re-inventory Aboveground biomassHuman disturbance Decadal change

Soil enzymatic activities and microbial community structure with different application rates of Cd and Pb

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Journal of environmental sciences 2007年第7期19卷 834-840页

作者： KHAN Sardar CAO Qing HESHAM Abd El-Latif XIA Yue HE Ji-zheng Research Center for Eco-environmental sciences Chinese Academy of Sciences Belting 100085 China. department of environmental sciences University of Peshawar 25120 Peshawar Pakistan

This study focused on the changes of soil microbial diversity and potential inhibitory effects of heavy metals on soil enzymatic activities at different application rates of Cd and/or Pb. The soil used for experiments was collected from Beijing and classified as endoaquepts. Pots containing 500 g of the soil with different Cd and/or Pb application rates were incubated for a period of 0, 2, 9, 12 weeks in a glasshouse and the soil samples were analyzed for individual enzymes, including catalase, alkaline phosphatase and dehydrogenase, and the changes of microbial community structure. Results showed that heavy metals slightly inhibited the enzymatic activities in all the samples spiked with heavy metals. The extent of inhibition increased significantly with increasing level of heavy metals, and varied with the incubation periods. The soil bacterial community structure, as determined by polymerase chain reaction- denaturing gradient gel electrophoresis techniques, was different in the contaminated samples as compared to the control. The highest community change was observed in the samples amended with high level of Cd. Positive correlations were observed among the three enzymatic activities, but negative correlations were found between the amounts of the heavy metals and the enzymatic activities.

关键词： soil contamination heavy metals application rate enzymatic activity microbial community

Exclosures restored the density and root colonization of arbuscular mycorrhizal fungi in Tigray, Northern Ethiopia

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Ecological Processes 2017年第1期6卷 339-350页

作者： Emiru Birhane Kide Mogos Gebremedihin Tewodros Tadesse Mengsteab Hailemariam Negasi Solomon department of Land Resources management and environmental protection Mekelle UniversityPO Box 231MekelleEthiopia Faculty of environmental sciences and Natural Resource management Norwegian University of Life SciencesPO Box 50031432ÅsNorway department of Natural Resource Economics and management Mekelle UniversityPO Box 231MekelleEthiopia

Introduction:Exclusion of grazing animals and tree plantations were among the methods used for the restoration of degraded lands in tropical semiarid *** can foster secondary forest succession by improving soil conditions and modifying microclimate for understory *** paper compared the arbuscular mycorrhizal fungi(AMF)spore density,root colonization of woody plants and soil chemical properties under exclosure with increasing age,and grazing land at different slope ***:The study was conducted in northern Ethiopia from 12 exclosure sites paired each with adjacent grazing land in total from 24 sites with four treatments replicated three *** the entire study,216 plots were examined of which 108 were in exclosures and 108 in communal grazing *** were four age classes and three slope positions in each of the land *** soil and root samples were collected using nested plots measuring 100m2 from four sides of 1763 plants for spore enumeration and root *** for chemical properties were collected from the four corners and center of 5 m×5 m ***:All the 61 woody plant species that belong to 41 families were colonized by *** density and root colonization were significantly higher in exclosures as compared to grazing land and increased with increasing ages of *** slope had significantly higher spore density and root colonization than middle and upper *** chemical properties were significantly higher in the exclosure,oldest age of exclosure,and foot slope position(except P).AMF spore density and root colonization were significantly positively correlated with soil chemical ***:Exclosures are helpful to restore the AMF spore density and root colonization of woody species and soil fertility.

关键词： Spore density Root colonization Age of exclosure Slope position

Geochemical Study of Rare Earth Elements on Four Attapulgite Clay Deposits in Jiangsu and Anhui Provinces,China

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Journal of Rare Earths 2003年第4期21卷 478-483页

作者：陈天虎徐晓春鲁安怀岳书仓汪家权彭书传 department of Resources and environmental sciences department of Geology

This paper discussed in detail about the REE component and the characteristics of the different kinds of attapulgite clay ores as well as basalts, weathered basalts in four localities of attapulgite clay deposits of Jiangsu and Anhui Provinces of China. It is concluded that the half weathered basalts have not distinct REE fractionation and strong weathered basalts have HREE loss in the process of the basalts weathered to form smectite group minerals. And the lateritic montmorillonite clays that formed from the basalts weathering have a distinct Ce positive anomaly, a little MREE loss and LREE and HREE renew enrichment. That reflects the particular oxidation condition in the Earth's surface and the adsorption of the colloid solution of the lake water in the basin of the continent in the time of the clays formed. The attapulgite clays produced by the reaction between basalts with lake water in the original place of the basin have same REE characteristics as that of the basalts and the weathered basalts. This shows that REE does not transfer heavily in the progressive chemical weathering process. The sedimentary attapulgite clays have also a similar REE component and characteristic parameters to the basalts and the weathered basalts, and have a distinct Eu negative anomaly and a big value of LREE/HREE, which shows that the sedimentary clay came from the weathered basalts, and REE partitioning patterns characters of the clays are controlled by the residual material of the weathered basalts.

关键词： geochemistry attapulgite basalt rare earths

A signal-substrate match in the substrate-borne component of a multimodal courtship display

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Current Zoology 2010年第3期56卷 370-378页

作者： Damian O.ELIAS Andrew C.MASON Eileen A.HEBETS department of environmental Science Policy and ManagementUniversity of California Integrative Behaviour and Neuroscience Group University of Toronto Scarborough School of Biological sciences University of Nebraska

The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at small scales. Nevertheless, natural selection is expected to select for signals well-suited for effective transmission. Here, we test for substrate-dependent signal efficacy in the wolf spider Schizocosa stridulans Strattou 1991. We first explore the transmission characteristics of this important signaling mo- dality by playing recorded substrate-bome signals through three different substrates （leaf litter, pine litter, and red clay） and measuring the propagated signal. We found that the substrate-bome signal of S. stridulans attenuates the least on leaf litter, the substrate upon which the species is naturally found. Next, by assessing mating success with artificially muted and non-muted males across different signaling substrates （leaf litter, pine litter, and sand）, we explored the relationship between substrate-bome signaling and signaling substrate for mating success. We found that muted males were unsuccessful in obtaining copulations re- gardless of substrate, while mating success was dependent on the signaling substrate for non-muted males. For non-muted males, more males copulated on leaf litter than any other substrate. Taken together, these results confLrm the importance of sub- strate-bome signaling in S. stridulans and suggest a match between signal properties and signal efficacy - leaf litter transmits the signal most effectively and males are most successful in obtaining copulations on leaf litter [Current Zoology 56 （3）： 370-378, 2010].

关键词： environmental heterogeneity Sensory drive Mate choice Communication

An exploratory study on the use of enzyme activities as sediment tracers:biochemical fingerprints?

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International Journal of Sediment Research 2011年第2期26卷 136-151页

作者： Kazem NOSRATI Gerard GOVERS Hassan AHMADI Forood SHARIFI Mohammad Ali AMOOZEGAR Roel MERCKX Matthias VANMAERCKE department of Physical Geography Faculty of Earth SciencesShahid Beheshti University Division of Geography Department of Earth and Environmental Sciences 3. Faculty ofNatural ResourcesUniversity of Tehran 4. ForestRange and Watershed Management Organization 5. Faculty of BiologyCollege of SciencesUniversity of Tehran 6. Division of Soil and Water ManagementDepartment of Earth and Environmental Sciences 7. Division of GeographyDepartment of Eaeth and Environmental Sciences

Little information exists on the potential of soil enzyme activities,which are sensitive to soil properties and management,for the characterization of sediment sources at the catchment *** objective of this study is to explore and evaluate enzyme activity as tracer for sediment fingerprinting in the Hiv catchment(55 km~2),***,four enzymes were measured from 42 different sampling sites,covering three sediment source areas(rangeland/surface erosion,orchard/surface erosion,and streambank erosion),as well as from 12 sediment samples from reservoir check dams (sediment sinks).The results indicate that,based upon backward mode discriminant analysis,βglucosidase and dehydrogenase,allowed more than 95%of the samples to be correctly assigned to their source *** enzymes were selected as input data for a mixing-model to determine the relative contribution of the sampled sediment *** mean contributions from rangeland, orchard and streambank sources in the study area were estimated as 11.3%,15.1%and 73.7%, *** geochemical tracers,the mean contribution from rangeland,orchard and streambank sources was estimated as 14.1%,9.5%and 74.8%,*** biochemical and geochemical tracers,similar values were obtained(18.7%,10.7%and 70.7%,respectively).Our results indicate that soil enzyme activity allows for a good characterization of sediment sources,and can provide a complementary tool to currently existing sediment fingerprinting ***, the method should be also tested in other regions.

关键词： Sediment source Enzyme activity Biochemical fingerprints Mixing model Hiv catchment

environmental sustainability of grey water footprints in Peshawar Basin:Current and future reduced flow scenarios for Kabul River

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International Journal of Agricultural and Biological Engineering 2019年第4期12卷 162-168页

作者： Tariq Khan Hizbullah Khan department of environmental sciences University of Haripur22640Pakistan department of environmental sciences University of Peshawar25000Pakistan

Assessing water pollution at basin level is a challenging *** this study,the environmental sustainability of grey water footprints(WFgrey)of Peshawar Basin in Pakistan was *** release of nitrogen(N)and phosphorus(P)from point and non-point sources during the period 1986 to 2015 were *** pollution level(WPL)for normal and 10%-50%future reduced runoff in Kabul River as a result of construction of dams was *** described in Water Footprint Assessment Manual and Grey Water Footprint Accounting Guidelines were *** showed that 30-year annual average of N and P discharges were 24.5×10^(3)t/a and 10.9×10^(4)t/a *** discharge of N and P from non-point sources contribute 97%and 99%respectively.N related WFgrey was 50×10^(8)m^(3)/a and 50×10^(9)m^(3)/a for *** of N was within the sustainable limit for all reduced runoff scenarios while P-related WPL for normal runoff exceeded sustainable limits and was worse in each reduced runoff *** study confirms the deteriorated water quality of Kabul River and the findings may be helpful for future planning and water resource management of the basin.

关键词： sustainability grey water footprint nitrogen phosphorus water pollution Kabul River Pakistan

Phanerozoic co-evolution of O2-CO2 and ocean habitability

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National Science Review 2024年第6期11卷 18-21页

作者： Zunli Lu Rosalind E.M.Rickaby Jonathan L.Payne Ashley N.Prow department of Earth & environmental sciences Syracuse University department of Earth sciences University of Oxford department of Earth and Planetary sciences Stanford University

Atmospheric carbon dioxide and oxygen concentrations are partially linked via the geological cycle of organic carbon （Fig. 1A–C; e.g. CO2+H2O■CH2O+O2）. The history of these two biologically active components, controls on their concentrations, and implications for the complexity of the biosphere and habitability of Earth have been hotly debated, but are generally considered independently.

关键词： ocean co-evolution habitability phanerozoic

2,3,7,8-Tetrachlorodibenzo-p-dioxin promotes migration ability of primary cultured rat astrocytes via aryl hydrocarbon receptor

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Journal of environmental sciences 2019年第2期31卷 368-376页

作者： Yangsheng Chen Rui Sha Li Xu Yingjie Xia Yiyun Liu Xuejun Li Heidi Qunhui Xie Naijun Tang Bin Zhao State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences University of Chinese Academy of sciences department of Occupational and environmental Health sTianjin Medical University

Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms are still unclear. During the process of astrocyte reactivation, migration is a critical cellular event. In the present study, we employed woundhealing assay and Transwell? motility assay to explore the effects of TCDD on cell migration in primary cultured rat cortical astrocytes. We found that upon TCDD treatments at relative low concentrations(10^(-10) and/or 10^(-9) mol/L), the ability of primary astrocytes to migrate horizontally and vertically was promoted. In line with this cellular effect, the mR NA expression of two promigratory genes, including cell division cycle 42(CDC42) and matrix metalloproteinase 2(MMP2)was induced by TCDD treatment. Dioxin exerts its toxic effects mainly through aryl hydrocarbon receptor(AhR) pathway. So the role of AhR pathway in the pro-migratory effects of TCDD was examined using an AhR antagonist, CH223191. We found that application of CH223191 significantly reversed the pro-migratory effects of TCDD. Interestingly, the basal ability of horizontal migration as well as basal levels of CDC42 and MMP2 expression were dramatically reduced suggesting a possible physiological role of AhR in maintaining the endogenous migration ability of the primary astrocytes. These findings support the notion that dioxin promotes astrocyte reactivation at molecular and cellular levels.

关键词： 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Astrocyte Migration Gene expression Aryl hydrocarbon receptor (AhR) pathway