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seasonal Effect of Geomorphological Chronosequence Features on soil Biota Dynamics

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Pedosphere 2010年第6期20卷 761-770页

作者： s.pen-mouratov N.GENZER N.sHUKUROV J.PLAKHT Y.sTEINBERGER The Mina & Everard Goodman Faculty of Life sciences Bar-Ilan University Institute of Geology and Geophysics Academy of Sciences Ramon science Center Jacob Blaustein Institute for Desert ResearchBen-Gurion University of the Negev

Numerous studies have been devoted to the physical-chemical weathering processes leading to the creation of unique soil formations having their own history that induce soil-biotic ***,the extent to which unique geomorphic formations influence soil biotic seasonal variation is not *** aim was to define seasonal variations of soil biota in soils of different-aged terraces of the Makhtesh Ramon anticline erosional cirque in southern *** strong effect of Makhtesh Ramon (Ramon crater) erosional fluvial terrace age initiated by climatic changes during the Late Pleistocene- Early Holocene period on seasonal variations in both soil properties and the abundance and composition of soil biota were ***,age dependence was not constant and values for observed soil properties and microbial activity were negligible between younger and older terraces for certain seasons,while free-living nematodes along with bacterial-feeding group were strongly dependent on the geomorphic features of the ages throughout the study period.

关键词： geomorphic formation Makhtesh Ramon microbial biomass nematode community trophic group

Do slope orientation and sampling location determine soil biota composition?

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Frontiers in Biology 2009年第3期4卷 364-375页

作者： s.pen-mouratov N.BERG N.GENZER s.UKABI D.sHARGIL Y.sTEINBERGER The Mina&Everard Goodman Faculty of Life sciences Bar-Ilan UniversityRamat-Gan 52900Israel

“Evolution Canyon”is a typical Mediterranean-basin canyon with a summer dry stream at the bottom and large differences in vegetation cover and solar radiation between the north-facing slope(NFs)and the south-facing slope(sFs).It is known to act as an abiotic mediator influencing the community structure of soil *** aim of this study was to determine the spatial dispersion of soil microbial and free-living nematode communities in the open sites(between shrubs)in the upper(0-10 cm)soil layer at four altitudes on both *** combination of relative soil moisture availability and temperature,known to be one of the main triggers for soil biota activity,was explained by slope *** above-mentioned differences were found to significantly affect microbial biomass and CO_(2)evolution resulting in temporary stress,corresponding to higher values in metabolic quotient(qCO_(2))*** differences may represent microbial investment in energy in order to overcome stress resulting from the microclimatic differences between the two ***,the degree of substrate limitation(primary production due to the differences in plant cover)of microbial activity was explained by the difference in microbial functional *** total abundance of soil free-living nematodes was found to be 2-fold higher on the sFs than on the ***-nine genera,including 12 bacteria-feeders,5 fungifeeders,12 plant-parasites,and 10 omnivore-predators,were found at the study site,with 34 genera on the NFs and 29 on the *** generic diversity of the bacteriafeeding nematodes was higher on the sFs than on the *** study elucidates the importance of slope orientation and its effect on the structural levels of soil microbial and nematode communities.

关键词： community structure “Evolution Canyon” free-living nematode sampling location slope orientation

spatio-Temporal Effect on soil Respiration in Fine-scale Patches in a Desert Ecosystem

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Pedosphere 2006年第1期16卷 1-9页

作者： s. pen-mouratov M. RAKHIMBAEV Y. sTEINBERGER Faculty of Life sciences Bar-Ilan University Ramat-Gan 52900 (Israel) Faculty of Life sciences Bar-Ilan University Ramat-Gan 52900 (Israel) Institute of Botany Tashkent (Uzbekistan)

soil organisms in terrestrial systems are unevenly distributed in time and space, and often aggregated. spatiotemporal patchiness in the soil environment is thought to be crucial for the maintenance of soil biodiversity, providing diverse microhabitats tightly interweaving with resource partitioning. Determination of a ＂scale unit＂ to help understand ecological processes has become one of the important and most debatable problems in recent years. A fieldwork was carried out in the northern Negev Desert highland, Israel to determine the influence of fine-scale landscape patch moisture heterogeneity on biogeochemical variables and microbial activity linkage in a desert ecosystem. The results showed that the spatio-temporal patchiness of soil moisture to which we attribute influential properties, was found to become more heterogenic with the decrease in soil moisture availability （from 8.2 to 0.4 g kg^-1） toward the hot, dry seasons, with coefficient of variation （CV） change amounting to 66.9%. spatio-temporal distribution of organic matter （OM） and total soluble nitrogen （TsN） was found to be relatively uniformly distributed throughout the wet seasons （winter and spring）, with increase of relatively high heterogeneity toward the dry seasons （from 0.25% to 2.17% for OM, and from 0 to 10.2 mg kg^-1 for TsN） with CV of 47.4% and 99.7% for OM and TsN, respectively. Different spatio-temporal landscape patterns were obtained for Ca （CV = 44.6%）, K （CV = 34.4%）, and Na （CV = 92%） ions throughout the study period. CO2 evolution （CV = 48.6%） was found to be of lower heterogeneity （varying between 2 and 39 g CO2-C g^-1 dry soil h^-1） in the moist seasons, e.g., winter and spring, with lower values of respiration coupled with high heterogeneity of Na^＋ and low levels of TsN and organic matter content, and with more homogeneity in the dry seasons （varying between 1 and 50 g CO2-C g^-1 dry soil h^-1）. Our results elucidate the heterogeneity and complexity of desert system habitats

关键词： desert microbial respiration patchiness small-scale habitat soil

soil Biota in the Arava Valley of Negev Desert,Israel

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Pedosphere 2010年第3期20卷 273-284页

作者： s. pen-mouratov T. MYBLAT I. sHAMIR G. BARNEss Y. sTEINBERGER The Mina & Everard Goodman Faculty of Life sciences Bar-Ilan University

soil microorganism biomass and respiration and the soil nematode community were observed in the hypersaline desert valley that is found between the Dead sea and the Red sea. The lowest point of the valley is approximately 400 m below sea level, and is the lowest point on earth. soil samples (n = 72) were collected from the 0-10 and 10-20 cm soil layers at different altitudes (from -400 to +100 m) in the open spaces between plants during one of the most extreme xeric periods. Both soil microbial respiration and microbial biomass were found to be negatively dependent on soil moisture (sM) and organic matter (OM), and positively dependent on pH values. The physical-chemical characteristics of this hypersaline area were extremely unfavorable for the soil nematode communities, and the nematodes were entirely absent in the open area below sea level. The bacterivores were found to be the most resistant nematodes in this hyperarid region, with the Wilsonema being the most widespread genus. We suggest that nitrogen availability may play a crucial role in the below-ground soil interaction in this region, with bacterivore nematodes as indicators of nitrogen availability.

关键词： Dead sea microbial biomass nematode community respiration trophic groups

The FRB-searching Pipeline of the Tianlai Cylinder Pathfinder Array

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Research in Astronomy and Astrophysics 2024年第8期24卷 113-132页

作者： Zijie Yu Furen Deng shijie sun Chenhui Niu Jixia Li Fengquan Wu Wei-Yang Wang Yougang Wang shifan Zuo Lin shu Jie Hao Xiaohui Liu Reza Ansari Ue-Li pen Albert stebbins Peter Timbie Xuelei Chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China Key Laboratory of Radio Astronomy and Technology Chinese Academy of ScienceBeijing 100101China Institute of Astrophysics Central China Normal UniversityWuhan 430079China Institute of Automation Chinese Academy of SciencesBeijing 100190China Guangdong Institute of Artificial Intelligence and Advanced Computing Guangzhou 510535China UniversitéParis-saclay CNRS/IN2P3IJCLab91405 OrsayFrance Institute of Astronomy and Astrophysics Academia SinicaRoosevelt RoadTaipei 10617TaiwanChina Canadian Institute for Theoretical Astrophysics University of Toronto60 Saint George StreetTorontoON M5S 3H8Canada Department of Physics University of Wisconsin-MadisonMadisonWI 53706USA Fermi National Accelerator Laboratory P.O.Box 500Batavia IL 60510-5011USA Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Center of High Energy Physics Peking UniversityBeijing 100871China

This paper presents the design,calibration,and survey strategy of the Fast Radio Burst(FRB)digital backend and its real-time data processing pipeline employed in the Tianlai Cylinder Pathfinder *** array,consisting of three parallel cylindrical reflectors and equipped with 96 dual-polarization feeds,is a radio interferometer array designed for conducting drift scans of the northern celestial *** FRB digital backend enables the formation of 96 digital beams,effectively covering an area of approximately 40 square degrees with the 3 dB *** pipeline demonstrates the capability to conduct an automatic search of FRBs,detecting at quasi-realtime and classifying FRB candidates *** current FRB searching pipeline has an overall recall rate of88%.During the commissioning phase,we successfully detected signals emitted by four well-known pulsars:PsR B0329+54,B2021+51,B0823+26,and B2020+*** report the first discovery of an FRB by our array,designated as FRB *** also investigate the optimal arrangement for the digitally formed beams to achieve maximum detection rate by numerical simulation.

关键词： instrumentation interferometers-methods data analysis-(stars )pulsars general-telescopes

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气动激励下的涡轮增压器整机振动分析与试验

内燃机学报 2024年第2期42卷 161-168页

作者：秦励伟刘贵升盆义红刘海景国玺张昊河北工业大学机械工程学院天津300130 天津市新能源汽车动力传动与安全技术重点实验室天津300130 中国北方发动机研究所柴油机增压技术重点实验室天津300400

针对气动激励引起的增压器整机高振动响应问题,以某型柴油发动机涡轮增压器为研究对象,采用单向瞬态流固耦合方法,建立涡轮增压器整机流固耦合模型,开展气动激励下关键零部件振动响应研究.讨论并对比了涡轮及压气机叶轮气动激励的时域... 详细信息

针对气动激励引起的增压器整机高振动响应问题,以某型柴油发动机涡轮增压器为研究对象,采用单向瞬态流固耦合方法,建立涡轮增压器整机流固耦合模型,开展气动激励下关键零部件振动响应研究.讨论并对比了涡轮及压气机叶轮气动激励的时域和频域特性,并定量分析了该激励下的结构振动响应特性,同时通过增压器振动试验验证了模型及方法的精度,各工况下壳体振动加速度量级的绝对误差不超过6 dB,相对误差不超过4%.结果表明:在转子系统中,压气机叶轮压力波动幅值为涡轮机涡轮的4倍,由此导致压气机叶轮的振动幅值平均为涡轮和转轴的3~4倍,最大振动幅值发生在压气机叶轮轮盘外边缘叶顶间隙处,为209.5μm;壳体振动烈度最大的部位发生在压气机出口内壁靠近轴承体一侧,为322.2 m/s^(2).

关键词：涡轮增压器气动激励流固耦合数值模拟

基于深度强化学习的园区综合能源系统低碳经济调度

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电网技术 2024年第9期48卷 3604-3613,I0022,I0023页

作者：杨挺刘豪王静党兆帅耿毅男盆海波智能电网教育部重点实验室(天津大学) 天津市南开区300072 深圳供电局有限公司广东省深圳市518000

为降低园区综合能源系统的运行成本和碳排放量,同时应对系统不确定性带来的随机波动,提出一种考虑阶梯式碳交易的园区综合能源系统低碳经济调度模型,并采用深度强化学习方法求解。首先构建园区阶梯式碳交易模型,将碳交易成本考虑在内对... 详细信息

为降低园区综合能源系统的运行成本和碳排放量,同时应对系统不确定性带来的随机波动,提出一种考虑阶梯式碳交易的园区综合能源系统低碳经济调度模型,并采用深度强化学习方法求解。首先构建园区阶梯式碳交易模型,将碳交易成本考虑在内对园区综合能源系统低碳经济调度问题进行数学描述;其次将该调度问题表述为马尔可夫决策过程框架,定义系统的观测状态、调度动作和奖励函数;继而采用近端策略优化算法进行低碳经济调度决策。所提方法无需进行负荷预测或不确定性建模,能够对源和荷的随机波动做出实时响应。最后基于多场景多算法进行算例仿真,结果表明所提方法提高系统运行经济性的同时降低了系统碳排放量。

关键词：园区综合能源系统阶梯式碳交易深度强化学习近端策略优化算法低碳经济调度

The effects of prescribed fire on soil nematodes in an arid juniper savanna

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Open Journal of Ecology 2014年第2期4卷 66-75页

作者： Walter G. Whitford stanislav pen-mouratov Yosef steinberger The Mina and Everard Goldman Faculty of Life sciences Bar-Ilan University Ramat-Gan Israel UsDA-ARs Jornada Experimental Range New Mexico State University Las Cruces USA

Prescribed fire produced a landscape with two types of severely burned patches: charred shrub patches and charred patches with tree trunks at the center. soil nematodes were more abundant in burned and unburned juniper (Juniperus monosperma) tree patches than in yucca-shrub patches. There were no differences in nematode abundance between burned and unburned patches during the late spring and summer samples. Nematode abundance was significantly (p s than in burned patches in the early spring samples, reflecting large differences in soil moisture between unburned and burned patches. There were no differences in soil nematode abundance between burned and unburned patches at oneyear post-burn and three-year post-burn sites. When all samples were pooled, taxonomic diversity, ecological indices, and abundance of trophic groups (bacteria-feeders, fungi-feeders, and omnivore-predators) were higher in unburned than burned patches. These results suggest that the long-term (up to three years post-burn) effects of fire on soil nematodes are indirect, i.e., by loss of tree canopies, litter accumulation, and shrub foliage, which affects soil temperatures and water redistribution.

关键词： Acrobeles Bacterivore Fungivore Omnivore-Predator Juniperus Monosperma soil Moisture Yucca Baccata

Changes in soil free-living nematode communities and their trophic composition along a climatic gradient

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Open Journal of Ecology 2012年第2期2卷 79-89页

作者： Tal Levi Chen sherman stanislav pen-mouratov Yosef steinberger The Mina & Everard Goodman Faculty of Life sciences Bar-Ilan University Ramat-Gan Israel

Ambiguity exists concerning the effects of climate on soil nematode-community composition. In this study, we examined the free-living nematode communities in soil along a climatic gradient representing humid-Mediterranean, Mediterranean, semi-arid, and arid climate types. The relationships between abiotic soil characteristics (organic carbon, soil moisture (sM), water-holding capacity) and nematode parameters, such as abundance, trophic group composition, and diversity indices, were explored in the context of climate and seasonality. Nematode abundance was lowest at the arid site. At the humid Mediterranean and Mediterranean locations, nematode abundance reached its peak in winter, while at the semi-arid and arid sites, an almost opposite trend was observed, with lowest abundances in winter, presumably due to a nutrient washout from the soil profile during the rainy season. On the trophic level, one trophic group demonstrated a positive correlation with sM and one trophic group demonstrated a negative one at each location, while the other two groups remained constant. Fungi-feeding nematodes were found to be unaffected by sM at the humid-Mediterranean and Mediterranean locations, while at the semi-arid and arid sites their proportion increased in correlation with decreasing sM. Bacteria-feeders increased with sM at the arid site, were unaffected at the semi-arid location, and decreased with sM at the humid-Mediterranean and Mediterranean sites. Plant-parasites were associated with sM only at the humid-Mediterranean site. Omnivores-predators were positively affected by sM at the two middle locations, staying constant at the humid-Mediterranean and arid sites. These findings point to the strong linkage existing between nematode trophic behavior and climatic factors, demonstrating distinctive communal fingerprints for each climate type.

关键词： Climate Gradient Diversity soil Nematode Trophic Group