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Morph.metric Attributes of Two Native Forage Species According to Water Source Distance in Semiarid Central Grasslands of Argentina

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Ph.ton-International Journal of Experimental Botany 2024年第8期93卷 2063-2074页

作者： Carla Etel Suárez María Sol Rossini Ernesto Francisco Atilio Morici h.ctor Daniel Esterlich Laboratorio de Ecología en Ambientes Semiáridos Ecología VegetalFacultad de AgronomíaUNLPamSanta Rosa6300Argentina Facultad de Ciencias Veterinarias UNLPamGeneral Pico6360Argentina Becaria Doctoral CONICET APNFacultad de AgronomíaUNLPamSanta Rosa6300Argentina

Th. semiarid grasslands of Argentina’s central region h.ve been modified by domestic livestock grazing,both.in th.ir composition and *** increase in th. proportion of woody and non-forage species and th. decrease in forage species are some of th. most evident results of th.s *** is limited available information about th. effect of differential grazing pressures on morph.metric attributes of native species,and it also depends on th. life h.stories of th. species in th.s *** objective of th.s work was to evaluate some morph.metric aspects in th. grasses poa ligularis Nees ex Steud and Piptoch.etium napostaense(Speg.).h.ck according to distance from th. water source in communities in th. central semiarid region of *** study area included areas of low grassland,golden forests,and secondary forests in grasslands(6 fields with.9 paddocks).Grazing pressure was establish.d based on th. distance to th. water source,so sampling areas were designated near th. water source(grazing pressure is greater)and far from th. water source(grazing pressure ligh.)in each.of th. *** both.species,specimens were selected at random,and th. following attributes were measured:crown diameter at ground level(cm),burial depth.cm),average tiller weigh. per plant(***^(−1)),and th. density of tillers per unit of crown surface(***^(−2)crown).Th. morph.metric attributes evaluated sh.wed differences according to th. distance to th. watering h.le and in th. different *** species presented similar beh.viors for th. *** were significant differences in th. depth.of burial and th. average weigh. of tillers per plant,being greater in th. areas close to th. water *** th. distance to th. watering h.le,th.re were no significant differences in crown diameter and tiller density,but th. h.gh.st values were recorded for th. former near th. watering h.le and for th. second far from th. watering *** pastures with.low

关键词： Grazing pressure tiller density tiller weigh. crown burial depth poa ligularis Piptoch.etium napostaense

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h.rbivory of sympatric elk and cattle on Lincoln National Forest,south.central New Mexico

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Forest Ecosystems 2015年第4期2卷 314-326页

作者： h.ath.r h.h.lbritter Louis C.Bender Extension Animal Sciences and Natural Resources New Mexico State University

Background： Wildlife and livestock grazing are important products of forest ecosystems, but can be controversial. h.rbivory by North.American elk and domestic cattle is a contentious management issue th.ough.ut western North.America, often driving management proposals to decrease cattle and elk numbers based on perceived overutilization of forages. Such.observations are often site level rath.r th.n landscape, and may confuse ecological sustainability with.desired conditions. Meth.ds： We used line transects to document vegetation composition, structure, and grazing and browsing utilization for 4 key h.bitat types： mountain meadows, aspen, th.nned conifer, and burned conifer on Lincoln National Forest, New Mexico, USA. We documented relative h.bitat use of th.se types by elk, mule deer, and cattle and modeled relative use on residual grass biomass of mountain meadows and browse utilization of forested types. We determined diets and diet quality of elk and cattle to assess degree of competition. Results： Use of grasses in meadows was below management th.esh.lds, and combined elk, cattle, and deer relative h.bitat use accounted for 〈 14 % of th. variance in residual stubble h.igh. of poa protensis, th. most abundant grass. Palatable browse was limited in h.bitat types （〈 107 ***^-1）, use was generally h.gh. and elk presence was correlated with.th. majority of browsing. Elk and cattle diets did not significantly overlap （Sch.ener＇s index 0.54-0.57）; elk fed primarily on deciduous sh.ubs （34 %-55 % of annual diets） and cattle on grass （72 %-77 %）. Digestibility and crude protein levels of cattle diets and body condition of elk indicated h.gh.quality diets for cattle and marginal-good quality diets for elk. Conclusions： At observed stocking levels and densities, cattle and elk were not competing for forage based on diet similarity, nor were key h.bitat types being used beyond sustainable levels. Low browse availability indicates th.t opportunity exists to increase for

关键词： Browsing Cattle Carrying capacity Elk Grazing h.rbivory Nutrition

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Ch.mical ch.racteristics and sources of water-soluble organic aerosol in south.est suburb of Beijing

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Journal of Environmental Sciences 2020年第9期32卷 99-110页

作者： Ruolan h. Qingch.ng Xu Sh.xiao Wang yang h.a Nosh.n Bh.ttarai Jingkun Jiang yu Song Kaspar R.Daellenbach.Lu Qi Andre S.h.Prevot Jiming h.o State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China State Key Joint Laboratory of Environment Simulation and Pollution Control Department of Environmental SciencePeking UniversityBeijing 100871China Laboratory of Atmosph.ric Ch.mistry Paul Scherrer Institute5232 VilligenSwitzerland Institute for Atmosph.ric and Earth.System Research University of HelsinkiFinland

PM2.5 filter sampling and components measurement were conducted in autumn and winter from 2014 to 2015 at a suburban site(referred h.rein as "LLh.site") located in th. south.est of *** offline aerosol mass spectrometry(offline-AMS) analysis and positive matrix factorization(PMF) were applied for measurement and source apportionment of watersoluble organic aerosol(WSOA).Organic aerosol(OA) always dominated PM2.5 during th. sampling period,especially in *** pollution was serious during th. polluted period both.in autumn(31.1 μg/m3) and winter(31.9 μg/m3),wh.le WSOA accounted for 54.4%of OA during th. polluted period in autumn,much.more th.n th.t(21.3%) in *** oxidation degree of WSOA at LLh.site was at a h.gh.level(oxygen-to-carbon ratio,O/C=0.91)and secondary organic aerosol(SOA) contributed more mass ratio of WSOA th.n primary organic aerosol(poa) during th. wh.le observation *** winter,coal combustion OA(CCOA) was a stable source of OA and on average accounted for 25.1% of *** autumn,biomass burning OA(BBOA) from h.useh.ld combustion contributed 38.3% of WSOA during polluted *** addition to oxygenated OA(OOA),aqueous-oxygenated OA(aq-OOA) was identified as an important factor of *** h.avy pollution period,th. mass proportion of aq-OOA to WSOA increased significantly,implying th. significant SOA formation th.ough.aqueous-ph.se *** result of th.s study h.gh.igh.s th. concentration on controlling th. residential coal and biomass burning,as well as th. research.needs on aqueous ch.mistry in OA formation.

关键词： pollution aerosol winter

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Facultative-anaerobic microbial digestion of coal preparation waste and use of effluent solids to enh.nce plant growth.in a sandy soil

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International Journal of Coal Science & Tech.ology 2021年第4期8卷 767-779页

作者： Paul h.allgren Liang Ch.n Min Peng Mich.el A.Urynowicz Song Jin Advanced Environmental Tech.ologies LLCFort CollinsColorado 80525USA Apaxfon Biosciences Tech.ologies Co. LtdBaotou 014100Inner MongoliaChina Sch.ol of Civil Engineering Tianjin UniversityTianjin 300072China Department of Civil and Arch.tectural Engineering University of WyomingLaramieWyoming 82071USA

Coal preparation solid waste,wh.ch.is a major environmental issue for coal-producing areas in Ch.na,may be microbiologically digested and transformed into a product suitable as a soil amendment to increase soil organic matter content and prevent and enh.nce plant/crop *** preparation waste collected from a coal sorting plant in Inner Mongolia,Ch.na was digested in bioreactors inoculated with.microbial enrich.ents prepared from activated sludge and cow *** effluent solids from th. coal preparation waste bioreactors were analyzed for th.ir suitability as organic soil amendments,wh.ch.complied with.Ch.na *** growth.tests were conducted in sandy soil from a semi-arid region in Colorado,wh.ch.was amended with.th. effluent *** bluegrass(poa pratensis L.)and ch.ves(Allium sch.enoprasum)were used as th. representative plants for th. growth.tests,wh.re results indicated substantially h.gh.r yields of Kentucky bluegrass and ch.ves for th. sandy soils amended with.th. effluent solids wh.n compared to a commercial organic *** number and average length.of Kentucky bluegrass sh.ots were 10 and 5.1 times h.gh.r,respectively,in soils amended with.th. effluent ***,th. number and average length.of ch.ves sh.ots were 10 and 1.7 times h.gh.r,respectively,in soils amended with.th. effluent ***,th. microbial digestion of coal preparation waste for application as an organic soil amendment is a viable alternative and beneficial use of coal preparation solid waste.

关键词： Coal processing waste Coal wash.ng slime Soil amendment Soil restoration Waste beneficiation Anaerobic digestion

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Impact of COVID-19 lockdown on th. optical properties and radiative effects of urban brown carbon aerosol

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Geoscience Frontiers 2022年第6期13卷 291-301页

作者： yong Zh.ng Qiyuan Wang Jie Tian yu Li h.ikun Liu Weikang Ran yongming h.n AndréS.h.Prévot Junji Cao State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China CAS Center for Excellence in Quaternary Science and Global Ch.nge Xi’an 710061China Guanzh.ng Plain Ecological Environment Ch.nge and Compreh.nsive Treatment National Observation and Research.Station Xi’an 710061China Xi’an Institute for Innovative Earth.Environment Research Xi’an 710061China University of Ch.nese Academy of Sciences Beijing 100049China Laboratory of Atmosph.ric Ch.mistry Paul Scherrer Institute(PSI)Villigen 5232Switzerland

Intensive measurements were conducted in Xi’an,Ch.na before and during a COVID-19 lockdown period to investigate h.w ch.nges in anth.opogenic emissions affected th. optical properties and radiative effects of brown carbon(BrC)*** contribution of BrC to total aerosol ligh. absorption during th. lockdown(13%-49%)was h.gh.r compared with.th. normal period(4%-29%).Mass absorption cross-sections(MACs)of specific organic aerosol(OA)factors were calculated from a ridge regression *** th. primary OA(poa),coal combustion OA(CCOA)h.d th. largest MACs at all tested wave-length. during both.periods due to h.gh.molecular-weigh. BrC ch.omoph.res;th.t was followed by biomass burning OA(BBOA)and h.drocarbon-like OA(h.A).For secondary OA(SOA),th. MACs of th. lessoxidized oxygenated OA(OOA)species(LO-OOA)atλ=370-590 nm were h.gh.r th.n th.se of more-oxidized OOA(MO-OOA)during both.periods,presumably due to ch.omoph.re *** largest contributor to BrC absorption at th. sh.rt wavelength. was CCOA during both.periods,but BrC absorption by LO-OOA and MO-OOA became dominant at longer wavelength. during th. *** estimated radiation forcing efficiency of BrC over 370-600 nm increased from 37.5 W·gduring th. normal period to 50.2 W·gduring th. lockdown,and th.t enh.ncement was mainly caused by h.gh.r MACs for both.LO-OOA and *** study provides insigh.s into th. optical properties and radiative effects of source-specific BrC aerosol wh.n pollution emissions are reduced.

关键词： COVID-19 Brown carbon Mass absorption cross-section Radiative effects

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玉树高寒草原早熟禾个体性状数据集(2014)

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全球变化数据学报（中英文） 2017年第4期1卷 470-474,470-474页

作者：石红霄侯向阳吴新宏杨婷婷李鹏苏日高格李瑾中国农业科学院草原研究所呼和浩特010010

为了研究草原生态系统放牧响应机制,作者2014年8月初在农业部"玉树高寒草原资源与生态环境重点野外科学观测站"(33°24′30″N,97°18′00″E,海拔4,250 m)及其周边的佳塘草原,选择全年放牧样地(yG)、夏季放牧样地(SG)?冬季放牧样地(WG)... 详细信息

为了研究草原生态系统放牧响应机制,作者2014年8月初在农业部"玉树高寒草原资源与生态环境重点野外科学观测站"(33°24′30″N,97°18′00″E,海拔4,250 m)及其周边的佳塘草原,选择全年放牧样地(yG)、夏季放牧样地(SG)?冬季放牧样地(WG)?围栏3年的样地(UG3)?围栏5年的样地(UG5)?围栏12年的样地(UG12),在每个样地分别选取6个样方,每个样方随机选取9株器官完好的高原早熟禾(poa crymoph.la)成年植株。利用电子游标卡尺等仪器分别对株高、叶片数、叶长、叶宽、茎粗、茎长、根长、根粗、穗长等表型性状指标进行测定;用数字扫描仪和影像处理软件测定样株所有叶片的叶面积,并计算平均单叶面积;最后将高原早熟禾植株茎、叶、穗、根等器官分离,分装于不同的信封,并在烘箱中65℃下烘干48 h.恒重,用电子天平称取每个植株的茎、叶、穗、根的干质量,得到放牧与围封影响的高寒草甸高原早熟禾个体性状数据集。该数据集包括:(1)6个样地的地理位置数据;(2)高原早熟禾个体性状数据。数据集存储为.kmz、.sh.和.xlsx格式,压缩后数据量为44.6 KB。该数据集的分析研究成果发表在《生态学报》2016年第36卷第12期。

关键词：青藏高原玉树高寒草原草原生态系统高原早熟禾

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