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Extensive pollen immigration and no evidence of disrupted mating patterns or reproduction in a highly fragmented holm oak stand

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Journal of Plant Ecology 2014年第4期7卷 384-395页

作者： Joaquín Ortego raúl Bonal Alberto Muñoz JoséMiguel Aparicio Grupo de Investigación de la Biodiversidad Genética y Cultural Instituto de Investigación en Recursos Cinegéticos-IREC(CSICUCLMJCCM)Ronda de Toledo s/nE-13005 Ciudad RealSpain Departamento de Ecología Evolutiva Museo Nacional de Ciencias Naturales(CSIC)C/JoséGutiérrez Abascal 2E-28006 MadridSpain Departamento de Didáctica de las Ciencias Experimentales Facultad de EducaciónUniversidad Complutense de MadridC/Rector Royo Villanova s/nE-28040 MadridSpain Centre de Recerca Ecològica i Aplicacions Forestals(CREAF) Cerdanyola del VallèsE-08193 BarcelonaSpain

Aims Forest fragmentation and reduced tree population densities can poten-tially have negative impacts on mating patterns,offspring genetic diversity and reproductive *** aim of the present study is to test these hypotheses comparing an extremely fragmented,low tree density(~0.02 trees/ha)holm oak(Quercus ilex l.)stand from Central spain with a nearby high tree density stand(~50 trees/ha).Methods We genotyped adult trees and seeds from the low-density stand(436 seeds from 15 families)and the high-density stand(404 seeds from 11 families)using nine microsatellite *** these data,we performed paternity analyses,determined pollen flow,mating patterns and pollen pool structure,and estimated progeny genetic diversity in both *** also studied seed set and production and performed a pollen supplementation experiment to determine whether reduced tree density has limited foreign pollen *** Findings We have found extensive pollen immigration(>75%)into the low tree density stand and monte Carlo simulations revealed that pollen moves larger distances than expected from null models of random *** patterns and differentiation of pollen pools were similar in the high-density stand and the low-density stand but we found higher inter-annual differentiation of pollen pools in the *** genetic diversity and self-fertilization rates did not dif-fer between the low-density stand and the high-density *** set rates were significantly lower in the low-density stand than in the high-density stand and experimental cross-pollen supplementation evidenced that foreign pollen availability is indeed a limiting factor in the ***,seed crops did not differ between the low-density stand and the high-density stand,indicating that limitation of foreign pollen is not likely to be of great concern in terms of reduced seed production and potential *** forest regeneration due to other ecological and human fac

关键词： forest fragmentation genetic diversity paternity analyses pollen dispersal pollen pool structure selfing tree density

Structural characteristics and formation process of pseudotachylyte in the Wulian detachment fault zone on the Jiaodong Peninsula， China

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Journal of Earth Science 2025年

作者： Ruijie Wang Jinlong Ni Guiyuan li Junlai liu lei Ji Yiren Wang Runye lü School of Earth Sciences and Engineering， Shandong University of Science and Technology Qingdao Geologic and Mineral Geotechnical Engineering Co.， ltd. State Key laboratory of Geological Processes and Mineral Resources， China University of Geosciences(Beijing) laboratory for Marine Mineral Resources，Qingdao Marine Science and Technology Center

Exploring pseudotachylytes (PSTs) within detachment fault zones provides valuable insight into the kinematic processes of these fault systems. Nevertheless， significant controversy persists regarding the origin and formation mechanisms of PST veins. The PST was initially identified within the Wulian detachment fault zone (DFZ) on the Jiaodong Peninsula by delineating the deformation characteristics of the fault zone's transition from ductile to ductile-brittle behavior. Macroscopic and microstructural features of the PST within the Wulian DFZ were examined using geological field surveys. Using quantitative and high-resolution techniques， such as scanning electron microscopy， TIMA-X mineral composition analysis， and transmission electron microscopy， variations in mineral composition between the veins and detritals of the PST were investigated. Furthermore， this study has investigated the progressive deformation processes and underlying causes contributing to PST formation within the DFZ. This study revealed the presence of both type D and B-type PSTs in the Wulian DFZ formed under ductile or ductile-brittle conditions. These PSTs exhibit fracture and fusion structures resulting from fault frictional fragmentation and frictional melting and undergo progressive deformation. During the initial stages of the D-type PST formation， biotite fragmentation in poorly cohesive foliation was the primary contributor， supplemented by frictional melting. As the deformation progressed， quartz fragmentation and partial melting became dominant， constituting up to 81.9% of the matrix. The formation of the B-type PST aligns with deformation under brittle or ductile-brittle conditions， with frictional fragmentation and fragmentation flow playing significant roles. Vein formation is initiated by biotite fragmentation or partial melting， followed by quartz， potassium feldspar， albite fragmentation， or partial melting. Mature PST veins exhibited distinct zoning characteristics， with a diffu

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Quality indicators in subtropical soils of Formosa,Argentina:Changes for agriculturization process

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International Soil and Water Conservation Research 2014年第4期2卷 13-24页

作者： Juan Esteban Baridón Roberto raúl Casas Universidad Nacional de la Plata Buenos AiresArgentina laboratorio de Suelos Aguas y Forrajes.Centro de Validación de Tecnologías Agropecuarias IbarretaIbarreta(CP 3624)FormosaArgentina Centro de Investigación de Recursos Naturales.Instituto Nacional de Tecnología Agropecuaria:Dr.Nicolás Repetto(ex las Cabañas)y los Reseros Castelar(CP1712)Buenos AiresArgentina

The agriculturization process has been defined as the advance of annual crops in different environments,in competition with traditional land uses such as agriculture rotations with *** Argentina and other countries agriculturization has different degrees of impact on natural *** the northeast region of the province of Formosa,Argentina,agriculturization includes deforestation(clear cutting,slash burning and plowing),technological improvements and changes in land *** of these alterations,it is necessary to define the state of the soil to evaluate its *** can be done by means of indicators,which are not universal;they differ according to the use,management and type of soils,weather conditions and *** objectives of this paper are:(1)To identify quality indicators for subtropical Argiudolls and Hapludolls;(2)To determine which indicators related to organic matter are most affected during *** changes produced in the Typic Hapludolls and Typic Argiudolls after 25 years of continuously using native forests,agriculture,fruit plantations and pastures were *** changes were in pH,electrical conductivity,total organic carbon,particulate organic carbon,total nitrogen,structural stability,hydraulic conductivity,respiration and dehydrogenase and urease and enzyme *** with significant differences between diverse uses were evaluated by multivariate methods,Principal Component Analysis,and Correlation *** results of this study showed that total organic carbon,particulate organic carbon,structural stability and dehydrogenase activity are the quality indicators most affected by *** are related to organic matter.

关键词： Hapludolls Argiudolls Soil quality Soil use

The importance of non-carbonate mineral weathering as a soil formation mechanism within a karst weathering profile in the SPECTra Critical Zone Observatory, Guizhou Province,China

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Acta Geochimica 2017年第3期36卷 566-571页

作者： Oliver W.Moore Heather l.Buss Sophie M.green Man liu Zhaoliang Song School of Earth Sciences University of Bristol Geography College of Life and Environmental SciencesUniversity of Exeter School of Water Resources and Environment China University of Geosciences (Beijing) Institute of the Surface-Earth System Science Research Tianjin University

Soil degradation, including rocky desertification,of the karst regions in China is severe. Karst landscapes are especially sensitive to soil degradation as carbonate rocks are nutrient-poor and easily eroded. Understanding the balance between soil formation and soil erosion is critical for long-term soil sustainability, yet little is known about the initial soil forming processes on karst terrain. Herein we examine the initial weathering processes of several types of carbonate bedrock containing varying amounts of non-carbonate minerals in the SPECTra Critical Zone Observatory, Guizhou Province, Southwest China. We compared the weathering mechanisms of the bedrock to the mass transfer of mineral nutrients in a soil profile developed on these rocks and found that soil formation and nutrient contents are strongly dependent upon the weathering of interbedded layers of more silicate-rich bedrock(marls). Atmospheric inputs from dust were also detected.

关键词： Critical zone Chemical weathering Karst Desertification Guizhou Province

Influence of flooding and vegetation on carbon,nitrogen,and phosphorus dynamics in the pore water of a Spartina alternifl.ra salt marsh

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Journal of Environmental Sciences 2011年第2期23卷 212-221页

作者： Vanesa l.Negrin Carla V.Spetter raúl O.Asteasuain Gerardo M.E.Perillo Jorge E.Marcovecchio Argentine Institute of Oceanography (IADO CONICETCCT-Bahía Blanca)Camino La Carrindanga km 75Building E-1 CC 804Bahía Blanca 8000Argentina Department of Chemistry Southern National Institute of Chemistry (INQUISUR)Southern National University (UNS)Av Alem 1253Bahía Blanca 8000Argentina Department of Geology Southern National University (UNS)San Juan 670Bahía Blanca 8000Argentina National Technological University Regional Faculty of Bahía Blanca (UTN-FRBB)11 de Abril 461Bahía Blanca 8000Argentina University of the Fraternity of Associations Santo Toms de Aquino (FASTA) Gascón 3145Mar del Plata 7600Argentina

Four sites were selected in a salt marsh in the Bahia Blanca Estuary （Argentina）：（1） low marsh （flooded by the tide twice daily） vegetated by S. alternifl.ra; （2） non-vegetated low marsh; （3） high marsh （flooded only in spring tides） vegetated by S. alternifl.ra; （4） non-vegetated high marsh. The pH and Eh were measured in sediments, while dissolved nutrients （ammonium, nitrate, nitrite and phosphate） and particulate organic matter （POM） were determined in pore water, pH （6.2-8.7） was only affected by vegetation in low areas. Eh （from -300 to 250 mV） was lower at low sites than at high ones; in the latter, the values were higher in the non-vegetated sediments. The POM concentration was greater in the high marsh than in the low marsh, with no effect of vegetation. Ammonium was the most abundant nitrogen nutrient species in pore water, except in the non-vegetated high marsh where nitrate concentration was higher. All nitrogen nutrients were affected by both flooding and vegetation. Phosphate was always present in pore water at all sites throughout the year and its concentration varied within narrow limits, with no effect of flooding and greater values always at non-vegetated sites. Our results showed that the variability of the pore water composition within the marsh is greater than the temporal variation, meaning that both tidal flooding and vegetation are important in the dynamics of nutrients and organic matter in the sediment pore water.

关键词： organic matter nutrients flooding Spartina alternifl.ra

MgO-based adsorbents for CO2 adsorption:Influence of structural and textural properties on the CO_2 adsorption performance

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Journal of Environmental Sciences 2017年第7期29卷 418-428页

作者： Gutiérrez-Bonilla Elvira Granados-Correa Francisco Sánchez-Mendieta Víctor Morales-luckie raúl Alberto National Institute of Nuclear Research Department of ChemistryA.P.18-1027Col.EscandonMigud Hidalgo DelegationZip Code 1180 Mexico D.F.Mexico Autonomous University of Mexieo State Faculty of ChemistryColon avenueintersection with ride Tollocan s/n TolucaMexicoMexico

A series of MgO-based adsorbents were prepared through solution–combustion synthesis and ball-milling *** prepared MgO-based powders were characterized using X-ray diffraction,scanning electron microscopy,N_2 physisorption measurements,and employed as potential adsorbents for CO_2 *** influence of structural and textural properties of these adsorbents over the CO_2 adsorption behaviour was also *** results showed that MgO-based products prepared by solution–combustion and ball-milling processes,were highly porous,fluffy,nanocrystalline structures in nature,which are unique physico-chemical properties that significantly contribute to enhance their CO_2 *** was found that the MgO synthesized by solution combustion process,using a molar ratio of urea to magnesium nitrate（2：1）,and treated by ball-milling during 2.5 hr（MgO-BM2.5h）,exhibited the maximum CO_2 adsorption capacity of 1.611 mmol/g at 25℃ and 1 atm,mainly via *** CO_2 adsorption behaviour on the MgO-based adsorbents was correlated to their improved specific surface area,total pore volume,pore size distribution and *** reusability of synthesized MgO-BM2.5h was confirmed by five consecutive CO_2adsorption–desorption times,without any significant loss of performance,that supports the potential of MgO-based *** results confirmed that the special features of MgO prepared by solution–combustion and treated by ball-milling during 2.5 hr are favorable to be used as effective MgO-based adsorbent in post-combustion CO_2 capture technologies.

关键词： CO_2 adsorption MgO-based adsorbents Porous materials Solution–combustion synthesis Ball-milling process Textural properties

Arylamine N-acetyl.ransferase 2 genotype-dependent N-acetylation of isoniazid in cryopreserved human hepatocytes

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Acta Pharmaceutica Sinica B 2017年第4期7卷 517-522页

作者： Mark A.Doll.raúl A.Salazar-González Srineil Bodduluri David W.Hein Department of Pharmacology and Toxicology and James Graham Brown Cancer Center University of LouisvilleLouisvilleKY 40202USA

Cryopreserved human hepatocytes were used to investigate the role of arylamine N-acetyl.ransferase 2 (NAT2; EC 2.***.1.5) polymorphism on the N-acetylation of isoniazid (INH). NAT2 genotype was determined by Taqman allelic discrimination assay and INH N-acetylation was measured by high performance liquid chromatography. INH N-acetylation rates in vitro exhibited a robust and highly significant (Plism. N-acetylation rates in situ were INH concentration- and time-dependent. Following incubation for 24 h with 12.5 or 100 µmol/l INH, acetyl-INH concentrations varied significantly (P = 0.0023 and P = 0.0002) across cryopreserved human hepatocytes samples from rapid, intermediate, and slow acetylators, respectively. The clear association between NAT2 genotype and phenotype supports use of NAT2 genotype to guide INH dosing strategies in the treatment and prevention of tuberculosis.

关键词： Isoniazid N-Acetyl.ransferase 2 Acetylation polymorphism Human hepatocytes Genotype Phenotype

Toward a Phylogeny of the Kukri Snakes,Genus Oligodon

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Asian Herpetological Research 2010年第1期1卷 1-21页

作者： Marc D.green Nikolai l.Orlov Robert W.Murphy Department of Natural History Royal Ontario Museum100 Queen’s Park TorontoON M5S 2C6 Canada Zoological Institute Russian Academy of SciencesUniversitetskaya nab 1 St.Petersburg 199034Russia State Key laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of Sciences

The South and Southeast Asian snake genus Oligodon, known for its egg-eating feeding behavior, has been a taxonomically and systematically challenging group. This work provides the first phylogenetic hypothesis for the genus. We use approximately 1900 base pairs of mitochondrial DNA sequence data to infer the relationships of these snakes, and we examine congruence between the phylogeny and hemipenial characters. A hypothesis for the position of Oligodon within the Colubridae is also proposed. We discuss the implications of the phylogeny for previous taxonomic groupings, and consider the usefulness of the trees in analysis of behavior and biogeography of this genus.

关键词： Oligodon genealogy Colubridae hemipenis mitochondrial DNA Southeast Asia South Asia

Improved estimation of PM_(2.5) brown carbon contributions to filter light attenuation

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Particuology 2021年第3期19卷 1-9页

作者： Judith C.Chow l.-W.Antony Chen Xiaoliang Wang Mark C.green John G.Watson Division of Atmospheric Sciences Desert Research InstituteRenoNVUSA State Key laboratory of loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’anChina Graduate Faculty Department of Atmospheric SciencesUniversity of NevadaReno NevadaUSA Department of Environmental and Occupational Health School of Public HealthUniversity of NevadaLas VegasNVUSA

Multiwavelength light attenuation measurements have been acquired as part of thermal/optical carbon analysis in the *** Speciation Network(CSN)and the Interagency Monitoring of PROtected Visual Environments(IMPROVE)network beginning in *** are used to estimate PM_(2.5)brown carbon(BrC)contributions to light absorption at various wavelengths,a useful method for separating biomass burning contributions from other *** of light transmitted through the filter deviates from Beers law as the mass of light absorbing materials *** study estimates the effects of these deviations with empirical adjustment factors applied to samples for CSN from 2016 to 2017 and for IMPROVE from 2016 to *** for the filter loading effect results in an annual average increase of∼6-7%BrC contribution to light attenuation:from 3.6%to 10.7%for the urban,more heavily loaded CSN samples;and from 23.7%to 29.5%for the non-urban IMPROVE *** alternative method is examined for BrC and black carbon(BC)adjustments by calculating the AbsorptionÅngström Exponent(AAE)for BC(i.e.,AAE_(BC))based on the ratios of 635 nm/780 nm light attenuation rather than assuming AAE_(BC)of *** paired-wavelength calculations result in a median AAE_(BC)of 0.76 for CSN and 0.8 for IMPROVE,with the majority of samples(i.e.,91%of CSN and 70%of IMPROVE)showing AAE_(BC)ligible contributions from BrC to AAE at longer wavelengths,the amount of light attenuation at shorter wavelengths(e.g.,405 nm)where BrC is dominant can be *** paired-wavelength method applied to the filter loading adjusted data has a greater effect on urban(fresh)than on non-urban(aged)aerosols,resulting in a factor of two increase in annual averaged BrC light attenuation(from 10.7%to 21.6%)for CSN and by a factor of 1.11(from 29.5%to 32.7%)for IMPROVE *** result demonstrates the importance of particle loading and AAE correction on quantifying BrC light attenuatio

关键词： Organic carbon Brown carbon Elemental carbon Black carbon AbsorptionÅngström Exponent