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Late Jurassic-Early Cretaceous tectonic switching in Liaodong Peninsula of the North China Craton and the implications for gold mineralisation

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Science China Earth Sciences 2021年第9期64卷 1537-1556页

作者： Dan-Ping YAN Ruoyan KONG Xiaoyu DONG Liang QIU Huilong LIU State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing100083China Geophysical investigation centre China Geological SurveyLangfang065000China

Constraining the processes of deformation during tectonic switching from compression to extension is difficult because of the scarcity or absence of associated sedimentary and magmatic rocks and weak *** east margin of the eastern North China Craton experienced Early to Middle Jurassic compression and Early Cretaceous ***,the period of tectonic quiescence lasting~13 million years(between 153 and 140 Ma)during which this transition occurred is poorly *** paper reports the identification of small-scale N-S-trending thrust and sinistral strike-slip faults(TSS)and NWtrending thrust and dextral strike-slip faults(TDS)in the Tongyuanpu-Aiyang region,which is part of the northern Liaodong *** of the tectonic stress field using striations,fault planes and kinematics reveals a NW-SE-oriented maximum principal axis(σ1),and sub-horizontalσ2 andσ*** of N-S-trending TSS and NW-trending TDS were arranged with right stepping and resulted in local uplift and erosion at the junctions between fault terminations,which partitioned the Early and Middle Jurassic basins into residual smaller volcanic-sedimentary *** basins were unconformably overlain by small Early Cretaceous volcanic-sedimentary basins,such as those at Tongyuanpu and *** ages and the timing of basin formation constrain the initiation of tectonic switching to 156–153 Ma,and its termination to 140–139 *** suggest that R-R’Riedel shears controlled the formation of the N-S-trending TSS and NW-trending *** R-R’shears were produced by continued sinistral strike-slip and northward growth along the Bohai Bay segment of the Tan-Lu fault zone during the Late Jurassic to early Early Cretaceous,simultaneous with a gradual weakening in the tectonic stress field during a switch in the direction of subduction of the Palaeo-Pacific plate from NW-ward to *** tectonic switching might have promoted the dissolution of gold and migra

关键词： Switch from compression-extension Liaodong Peninsula Late Jurassic-Early Cretaceous R-R’shear Tan-Lu fault zone gold mineralisation

Does litterfall from native trees support rainfed agriculture? Analysis of Ficus trees in agroforestry systems of southern dry agroclimatic zone of Karnataka, southern India

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Journal of Forestry Research 2013年第2期24卷 333-338页

作者： B. Dhanya Syam Viswanath Seema Purushothaman Tree improvement and Propagation Division Institute of Wood Science and Technology College of Agriculture University of Agricultural Sciences centre for environment and Development Ashoka Trust for Research in Ecology and the Environment

Trees of the genus Ficus, integral components of indigenous rainfed agro-ecosystems of the southern dry agro-climatic zone of Karnataka, southern India, have traditionally been associated with the ecological service of soil quality enhancement in addition to various direct use benefits. We assessed the soil enrichment service of Ficus benghalensis L. a common Ficus species in these agroforestry systems, by quantifying nutrient return via litter fall. Litterfall estimation and chemical analysis of litter showed that F. benghalensis trees produce 3,512 kg ha-1 of litter annually which, on decomposition, can satisfy up to 76.70 % of N, 20.24% of P and 67.76% of K requirements of dryland crops annually per hectare. This can lead to an avoided cost of compost of US $ 36.46 ha-1·a-1 in dryland farming systems. The slow rate of decay of Ficus litter, as revealed in litter decomposition studies indicates its potential as ideal mulch for dryland soils. We discuss the complementarity between Ficus litterfall and cropping patterns in Mandya, and its implications for rainfed agricultural systems.

关键词： soil enrichment litter traps litter bags litter decomposition complementarity

Modelling monthly soil losses and sediment yields in Cyprus

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International Journal of Digital Earth 2016年第8期9卷 766-787页

作者： Christos G.Karydas Panos Panagos School of Agriculture Forestry and Natural environment Aristotle University of ThessalonikiThessalonikiGreece European Commission Joint Research CentreInstitute of Environment and SustainabilityIspraVAItaly

The aim of this study was to map soil erosion on the Mediterranean island of *** G2 model,an empirical model for month-time step erosion assessments,was *** losses in Cyprus were mapped at a 100 m cell size,while sediment yields at a sub-basin scale of 0.62 km^(2) mean *** results indicated a mean annual erosion rate of 11.75 t ha^(−1)y−^(1),with October and November being the most erosive *** 34%of the island’s surface was found to exceed non-sustainable erosion rates(>10 t ha^(−1)y−^(1)),with sclerophyllous vegetation,coniferous forests,and non-irrigated arable land being the most extensive non-sustainable erosive land *** mean sediment delivery ratio(SDR)was found to be 0.26,while the mean annual specific sediment yield(SSY)value for Cyprus was found to be 3.32 t ha^(−1)y−^(1).The annual sediment yield of the entire island was found to be 2.746 Mt y−*** study was the first to provide complete and detailed erosion figures for Cyprus at a country *** geodatabase and all information records of the study are available at the European Soil Data centre(ESDAC)of the Joint Research centre(JRC).

关键词： Soil erosion G2 model USLE Gavrilovic digital earth

The Changing Cold Regions Network:Observation,diagnosis and prediction of environmental change in the Saskatchewan and Mackenzie River Basins,Canada

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Science China Earth Sciences 2015年第1期58卷 46-60页

作者： Chris M DEBEER Howard S WHEATER William L QUINTON Sean K CAREY Ronald E STEWART Murray D MACKAY Philip MARSH Global Institute for Water Security University of SaskatchewanNational Hydrology Research Centre Cold Regions Research centre Wilfrid Laurier University School of Geography and Earth Sciences Mc Master University Department of environment and Geography University of Manitoba Science and Technology Branch Environment Canada

Climate change is causing rapid and severe changes to many Earth systems and processes,with widespread cryospheric,ecological,and hydrological impacts globally,and especially in high northern *** is of major societal concern and there is an urgent need for improved understanding and predictive tools for environmental *** Changing Cold Regions Network(CCRN)is a Canadian research consortium with a focus to integrate existing and new experimental data with modelling and remote sensing products to understand,diagnose,and predict changing land,water,and climate,and their interactions and feedbacks over the geographic domain of the Mackenzie and Saskatchewan River Basins in *** network operates a set of 14 unique and focused Water,Ecosystem,Cryosphere and Climate(WECC)observatories within this region,which provide opportunities to observe and understand processes and their interaction,as well as develop and test numerical simulation models,and provide validation data for remote sensing *** paper describes this network and its observational,experimental,and modelling *** overview of many of the recent Earth system changes observed across the study region is provided,and some local insights from WECC observatories that may partly explain regional patterns and trends are *** of the model products being developed are discussed,and linkages with the local to international user community are reviewed—In particular,the use of WECC data towards model and remote sensing product calibration and validation is *** future activities and prospects for the network are also presented at the end of the paper.

关键词： climate change cryosphere hydrology atmospheric science ecology modelling Canada

Adsorption behavior of imidacloprid pesticide on polar microplastics under environmental conditions:critical role of photo-aging

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Frontiers of environmental Science & Engineering 2023年第4期17卷 13-26页

作者： Weiyi Liu Ting Pan Hang Liu Mengyun Jiang Tingting Zhang Department of environmental Science and Engineering Research Centre for Resource and EnvironmentBeijing University of Chemical TechnologyBeijing 100029China

The photo-aging behavior of microplastics(MPs)in natural environment has become a global *** ultraviolet radiation has enough energy to change the polymer structure and physicalchemical properties of *** attention has focused on the interactions of the photo-aged polar and biodegradable MPs with organic *** work investigated the structural properties of aged polar polyamide(PA)MPs and biodegradable polylactic acid(PLA)MPs exposed to ultraviolet irradiation and their adsorption behavior and mechanism for neonicotinoid insecticide imidacloprid(IMI).The results showed that the MPs had extensive changes in surface morphology and chemical properties after *** C–N bond of PA MPs was disrupted to form more carbonyl *** oxygen-containing functional groups on the surface of aged PLA MPs were broken and generated relatively smaller *** adsorption capacity of IMI on PA MPs decreased by 19.2%,while the adsorption capacity of IMI on PLA MPs increased by 41.2%after *** depended on the natural structure of the MPs and their ability to absorb ultraviolet *** electrostatic interactions,hydrogen bonds,van der Waals interactions,and polar-polar interactions were the main adsorption mechanisms of IMI on *** initial solution pH and low ionic strength favored the adsorption of IMI by altering charge distribution on the MPs *** formation of the humic acid-IMI complexes decreased the concentration of IMI in the water phase and further decreased the adsorption on *** results are enlightening for a scientific comprehension of the environmental behavior of the polar MPs.

关键词： Microplastics Neonicotinoid insecticide Photo-aging adsorption environmental conditions

Contribution of precursor compounds to the release of per-and polyfluoroalkyl substances(PFASs) from waste water treatment plants(WWTPs)

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Journal of environmental Sciences 2017年第11期29卷 80-90页

作者： Ulrika Eriksson Peter Haglund Anna K?rrman Man-Technology-environment (MTM) Research centre School of Science and Technology ?rebro University Department of Chemistry Umea University

Per-and polyfluoroalkyl substances（PFASs） are ubiquitous in sludge and water from waste water treatment plants, as a result of their incorporation in everyday products and industrial processes. In this study, we measured several classes of persistent PFASs,precursors, transformation intermediates, and newly identified PFASs in influent and effluent sewage water and sludge from three municipal waste water treatment plants in Sweden, sampled in 2015. For sludge, samples from 2012 and 2014 were analyzed as *** of precursors in sludge exceeded those of perfluoroalkyl acids and sulfonic acids（PFCAs and PFSAs）, in 2015 the sum of polyfluoroalkyl phosphoric acid esters（PAPs） were 15–20 ng/g dry weight, the sum of fluorotelomer sulfonic acids（FTSAs） was 0.8–1.3 ng/g,and the sum of perfluorooctane sulfonamides and ethanols ranged from non-detected to 3.2 ng/g. Persistent PFSAs and PFCAs were detected at 1.9–3.9 ng/g and 2.4–7.3 ng/g dry weight, respectively. The influence of precursor compounds was further demonstrated by an observed substantial increase for a majority of the persistent PFCAs and PFSAs in water after waste water treatment. Perfluorohexanoic acid（PFHxA）, perfluorooctanoic acid（PFOA）, perfluorohexane sulfonic acid（PFHxS）, and perfluorooctane sulfonic acid（PFOS）had a net mass increase in all WWTPs, with mean values of 83%, 28%, 37% and 58%,respectively. The load of precursors and intermediates in influent water and sludge combined with net mass increase support the hypothesis that degradation of precursor compounds is a significant contributor to PFAS contamination in the environment.

关键词： diPAPs FTSAs Waste water Daily discharge PFCA precursor

Hydrocarbons in particulate samples from wildfire events in central Portugal in summer 2010

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Journal of environmental Sciences 2017年第3期29卷 122-131页

作者： Ana Vicente Ana Calvo Ana P.Fernandes Teresa Nunes Cristina Monteiro Casimiro Pio Célia Alves centre for environmental and Marine Studies (CESAM) Department of EnvironmentUniversity of Aveiro Department of Physics IMARENABUniversity of León

In summer 2010, twenty eight （14 PM=2.5 samples plus 14 samples PM2.5-10） smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse （PM=2.5-10） and fine （PM2.5） smoke samples. The carbonaceous content （elemental and organic carbon） of particulate matter was analysed by a thermal-optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatog- raphy into three different classes of organic compounds （aliphatics, polycyclic aromatic hydrocarbons （PAHs） and carbonyl compounds）. The organic speciation was performed by gas chromatography-mass spectrometry （GC-MS）. Emissions were dominated by the fine particles, which represented around 92% of the PM10. A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon （OC/EC） ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone 6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic com- pounds and secondary processing accounted for 97% of the apportioned PM2.5 levels.

关键词： WildfiresOrganic carbonOrganic compoundsBiomarkersParticulate matterPortugal

environmental application and ecological significance of nano-zero valent iron

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Journal of environmental Sciences 2016年第6期28卷 88-98页

作者： Biruck D.Yirsaw Mallavarapu Megharaj Zuliang Chen Ravi Naidu centre for environmental Risk Assessment and Remediation(CERAR) University of South Australia and CRC for Contamination Assessment and Remediation of the Environment(CRCCARE)

Toxicity studies considering both the bare and stabilized forms of zero valent iron nanoparticles（nZVI） could be timely, given that ecological risks identified are minimized through modification or with substitution of approaches in the synthesis, development and environmental application of the nanoparticles before succeeding to volume *** review is focused on the fate, transport and toxicological implications of the bare nZVI and surface modified particles used for environmental applications.

关键词： Nano zero valent iron Stabilized form of nZVI Toxicity

Aggregate Development and Organic Matter Storage in Mediterranean Mountain Soils

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Pedosphere 2010年第6期20卷 702-710页

作者： R.M.POCH M.ANTúNEZ Department of environment and Soil Science University of Lleida. centre Tecnològic Forestal de Catalunya

Soil aggregation and organic matter of soils from the pre-Pyrenean range in Catalonia (NE Spain) were studied,in order to assess their quality as carbon sinks and also to select the best soil management practices to preserve their *** stability,organic carbon and micromorphology were *** highest amount of organic carbon was found in alluvial,deep soils (228 Mg C ha -1 ),and the lowest was in a shallow,stony soil with a low plant cover (78 Mg C ha -1 ).Subsurface horizons of degraded soils under pastures were the ones with smaller and less-stable *** residues of organic matter (OM) were found mostly in interaggregate *** the aggregates there were some organic remains that were beginning to decompose,and also impregnative nodules of amorphous *** OM was evenly distributed among the aggregate fractions,the larger blocky peds had more specific surface,contained less decomposed OM and had a lower organic/mineral interphase than smaller crumb aggregates,which were also more *** carbon storage was affected primarily by the OM inputs in the surface *** order to store organic carbon over the mid- and long-term periods,the mechanisms favouring structuration through biological activity and creating small aggregates with intrapedal stable microporosities seemed to be the most effective.

关键词： aggregate stability Catalonia macroaggregates organic carbon soil carbon storage