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Regenerative Role of Soil Seed Banks of Different Successional Stages in A Saline-alkaline Grassland in Northeast China

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Chinese Geographical Science 2018年第4期28卷 694-706页

作者： MA Hongyuan LI Jingpeng YANG Fan Lü Xiaotao PAN Yuepeng liang zhengwei Da'an Sodic Land Experiment Station Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Erguna Forest-Steppe Ecotone Research Station Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospherie Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Soil seed banks can act as a potential seed source for natural revegetation and restoration. However, in a saline-alkaline grassland, it remains unclear how the stages of vegetation succession affect the characteristics of soil seed banks and the potential of soil seed banks of different successional stages for vegetation restoration. In this study, seasonal changes of the soil seed bank, and seed production and dispersal dynamics along degradation successional gradients were investigated in a saline-alkaline grassland in Northeast China, where the dominant grass during the 1960 s, Leymus chinensis was replaced with the secondary successional order of Puccinellia chinampoensis, Chloris virgata, and Suaeda salsa, together with bare patches. It was found that the soil seed bank composition varied according to the changing vegetation and had the highest species richness(7–16) in the climax successional stage, but had a low S?rensen similarity(0.22–0.37) with the aboveground vegetation. There was a high seed density of the soil seed bank(21 062–62 166/m2 in August and December) and also high S?rensen similarity index values(0.47–0.60) in the secondary successional stages of P. chinampoensis, C. virgata, and S. salsa. In bare patches, there were many seeds in the soil seed bank and some seedlings also appeared in the aboveground vegetation, indicating the existence of a persistent soil seed bank. Seed density and species richness differed substantially among the different successional stages, which was related to the reproductive characteristics of the standing plants in vegetation communities. Due to the lack of propagules of perennial species, especially the climax species of L. chinensis, in the soil, the successful restoration of the degraded saline-alkaline grassland was not possible. The study proved that in a degraded saline-alkaline grassland dominated by biennial or annual species, the soil seed bank was important for the revegetation of the current dominant pla

关键词： soil seed bank seed dispersal ecological restoration phenology succession seed rain

Role of endogenous hormones,glumes,endosperm and temperature on germination of Leymus chinensis(Poaceae)seeds during development

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Journal of Plant Ecology 2010年第4期3卷 269-277页

作者： Hongyuan Ma zhengwei liang Haitao Wu Lihua Huang Zhichun Wang Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun 130012People’s Republic of China Da’an Sodic Land Experiment Station of China Da’an 131317People’s Republic of China

Aims Leymus chinensis is an original dominant plant in the Songnen grassland,and it has great value for restoration of severely degraded ***,seeds are dormant,and low germination percentage is a problem for restoring *** *** mechanism of seed dormancy is not been well *** primary aims of the present study were to investigate the dormancy mechanism of *** seeds(caryopses)with reference to the role of embryo-covering layers,endogenous hormones and *** Changes in concentration of the endogenous hormones GA3,indoleacetic acid(IAA),zeatin riboside(ZR)and abscisic acid(ABA)in *** seeds fromanthesis to maturity weremeasured by the enzymelinked immunosorbent assay *** at different stages of maturity were tested at 16/28C,5/28C and 5/35C for intact seeds with glumes(control),intact seeds with glumes removed(nakedwhole seeds)and intact seeds with glumes and one-half of the endosperm removed(naked-half seeds).Important Findings Of the four endogenous hormones monitored,only the concentration of ZR differed significantly between the beginning and the end of seed development(increased);the GA3/ABA ratio also did not *** of germination percentage of control at the three temperature regimens was 5/28C>16/28C>5/35*** percentage of the naked-half seeds reached 100%under the three temperature *** concluded that dormancy of *** seeds is not mainly controlled by endogenous *** temperature,mechanical resistance of glumes and inhibition of endosperm are the main factors controlling dormancy and germination of *** seeds.

关键词： endogenous hormones temperature Leymus chinensis anthesis seed germination

RNAi-mediated suppression of the abscisic acid catabolism gene Os ABA8ox1 increases abscisic acid content and tolerance to saline–alkaline stress in rice(Oryza sativa L.)

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The Crop Journal 2022年第2期10卷 354-367页

作者： Xiaolong Liu Xianzhi Xie Chongke Zheng Lixing Wei Xiaowei Li Yangyang Jin Guohui Zhang Chang-Jie Jiang zhengwei liang Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102JilinChina Shandong Rice Research Institute Shandong Academy of Agricultural SciencesJinan 250100ShandongChina College of Life Science and Resources and Environment Yichun UniversityYichun 336000JiangxiChina Da’an Sodic Land Experiment Station Da’an 131317JilinChina Dongying Academy of Agricultural Sciences Dongying 257091ShandongChina College of Life Sciences Engineering Research Center of the Chinese Ministry of Education for Bioreactor and Pharmaceutical DevelopmentJilin Agricultural UniversityChangchun 130118JilinChina Institute of Agrobiological Sciences NAROKannondai 2-1-2Tsukuba 305-8602Japan

Saline–alkaline(SA) stress is characterized by high salinity and high alkalinity(high p H), which severely inhibit plant growth and cause huge losses in crop yields worldwide. Here we show that a moderate elevation of endogenous abscisic acid(ABA) levels by RNAi-mediated suppression of Os ABA8 ox1(Os ABA8 ox1-kd), a key ABA catabolic gene, significantly increased tolerance to SA stress in rice plants. We produced Os ABA8 ox1-kd lines in two different japonica cultivars, Dongdao 4 and Nipponbare. Compared with nontransgenic control plants(WT), the Os ABA8 ox1-kd seedlings accumulated 25.9%–55.7% higher levels of endogenous ABA and exhibited reduced plasmalemma injury, ROS accumulation and Na;/K;ratio, and higher survival rates, under hydroponic alkaline conditions simulated by 10, 15, and 20 mmol L-1 of Na;CO;. In pot trials using SA field soils of different alkali levels(p H 7.59, 8.86, and 9.29), Os ABA8 ox1–kd plants showed markedly higher seedling survival rates and more vigorous plant growth, resulting in significantly higher yield components including panicle number(85.7%–128.6%), spikelets per panicle(36.9%–61.9%), branches(153.9%–236.7%), 1000–kernel weight(20.0%–28.6%), and percentage of filled spikelets(96.6%–1340.8%) at harvest time. Under severe SA soil conditions(p H = 9.29, EC = 834.4 μS cm-1),Os ABA8 ox1-kd lines showed an 194.5%–1090.8% increase in grain yield per plant relative to WT *** results suggest that suppression of Os ABA8 ox1 to increase endogenous ABA levels provides a new molecular approach for improving rice yield in SA paddies.

关键词： Rice(Oryza sativa L.) Saline–alkaline stress Abscisic acid(ABA) OsABA8ox1-kd Endogenous ABA levels

铀“稳定”同位素分馏及其在地球科学中的应用

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地球科学 2021年第12期46卷 4405-4426页

作者：梁正伟田世洪东华理工大学核资源与环境国家重点实验室江西南昌330013

铀"稳定"同位素(^(238)U/^(235)U,通常记为δ^(238)U)目前已经成为非传统稳定同位素领域的研究热点.20世纪人们曾经认为铀同位素不存在分馏,因而铀同位素研究发展缓慢.然而随着分析技术的发展,人们发现自然界中铀同位素^(238)U和^(235)... 详细信息

铀"稳定"同位素(^(238)U/^(235)U,通常记为δ^(238)U)目前已经成为非传统稳定同位素领域的研究热点.20世纪人们曾经认为铀同位素不存在分馏,因而铀同位素研究发展缓慢.然而随着分析技术的发展,人们发现自然界中铀同位素^(238)U和^(235)U存在显著的分馏,可以作为良好的示踪工具.迄今为止,已经有大量铀同位素作为古氧化还原指标的研究发表,比如用铀同位素示踪地球近地表环境氧含量随时间的演化以及生物大灭绝与海洋氧化还原状态之间的潜在关系.尽管铀同位素在水圈和生物圈协同演化领域取得了丰硕的研究成果,但仍有不少问题亟待深入解决.例如,生物和非生物还原高价铀的微观反应过程对铀同位素分馏的影响,以及铀同位素如何示踪铀矿物质来源等.系统总结了铀同位素地球化学最近十年的研究进展,希望将来铀同位素在铀多金属矿床成因和高温地球化学领域能有所突破.

关键词：铀同位素分馏机理示踪氧含量生物灭绝氧化还原状态铀矿地球化学

不同pH值土壤及其浸提液对羊草种子萌发和幼苗生长的影响

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植物学通报 2007年第2期24卷 181-188页

作者：马红媛梁正伟中国科学院东北地理与农业生态研究所

研究了不同pH值土壤以及重度盐碱土和非盐碱土浸提液对羊草(Leymus chinensis)种子萌发及幼苗生长的影响。不同pH值土壤由配土和调酸两种方式取得,前者由重度盐碱土(pH=10．24)与非盐碱土(pH=7．49)按不同比例配制,后者是由重度苏打盐... 详细信息

研究了不同pH值土壤以及重度盐碱土和非盐碱土浸提液对羊草(Leymus chinensis)种子萌发及幼苗生长的影响。不同pH值土壤由配土和调酸两种方式取得,前者由重度盐碱土(pH=10．24)与非盐碱土(pH=7．49)按不同比例配制,后者是由重度苏打盐碱土经硫酸调酸处理得到。配土发芽的实验结果表明,当pH值在7．49-9．14时,种子的发芽率均在50％以上,且幼苗能够正常生长;pH=9．53时,羊草种子的发芽率低于50％,仅部分幼苗个体能够成活;当pH>9．86时,幼苗在萌发后50天左右全部枯死。说明羊草种子个体萌发期最大耐受pH值在9．14-9．53之间。重度苏打盐碱土调酸发芽实验结果表明,当调酸后的土壤pH值降至7．0-10．0时,均能显著促进羊草种子的萌发,且幼苗生长正常。确定了羊草种子萌发的最适pH值为8．0-8．5。土／水比为1:1的非盐碱土浸提液能够显著提高羊草种子发芽率,而重度苏打盐碱土浸提液对羊草种子萌发没有产生显著抑制。

关键词：萌发羊草非盐碱土 pH值盐碱土浸提液

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锌同位素在地球科学研究中的新进展

地质学报 2023年第4期97卷 1002-1029页

作者：黄施棋龚迎莉田世洪梁正伟朱春会东华理工大学核资源与环境国家重点实验室江西南昌330013 东华理工大学地球科学学院江西南昌330013 清华大学能源与动力工程系北京100084 自然资源部深地科学与探测技术实验室北京100094 贵州同微测试科技有限公司贵州贵阳550025

作为“金属稳定同位素家族”中的重要成员之一,锌同位素自20世纪就受到了国际地学界的关注。进入21世纪后,随着多接收电感耦合等离子体质谱仪(MC-ICP-MS)测试技术的发展,锌同位素在地球及行星科学中的应用得到了极大拓展。本文比较全面... 详细信息

作为“金属稳定同位素家族”中的重要成员之一,锌同位素自20世纪就受到了国际地学界的关注。进入21世纪后,随着多接收电感耦合等离子体质谱仪(MC-ICP-MS)测试技术的发展,锌同位素在地球及行星科学中的应用得到了极大拓展。本文比较全面地总结了锌同位素的标准物质和分析测试方法、自然界主要储库的锌同位素组成、锌同位素在不同地质过程中的行为及分馏机理,以及锌同位素在地球科学研究的新进展,包括:(1)示踪再循环沉积碳酸盐和再循环洋壳以及约束玄武岩成分变化机制;(2)示踪成矿物质来源、微生物成矿以及指示矿产勘查;(3)揭示月球的起源与演化过程;(4)指示初级生产力和有机质埋藏变化等生物地球化学过程以及揭示生物灭绝机制。未来,随着锌同位素微区原位分析技术的发展,锌同位素必将在地球科学(尤其是矿床学)和生物医学等领域中得到更加深入与广泛的应用。

关键词：锌同位素分析方法主要储库分馏机理新进展

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经济新常态下民营企业的经营困境与纾解策略

北京工业职业技术学院学报 2023年第2期22卷 102-105页

作者：梁政伟广东理工学院广东肇庆526040

为继续发挥民营企业对我国经济高质量发展的带动作用,对经济新常态下民营企业的经营困境与纾解策略进行了研究。当前,我国民营企业面临融资难度较大、综合素质较低、财务管理不科学、转型竞争力不足的困境,对企业充分释放发展潜力形成制... 详细信息

为继续发挥民营企业对我国经济高质量发展的带动作用,对经济新常态下民营企业的经营困境与纾解策略进行了研究。当前,我国民营企业面临融资难度较大、综合素质较低、财务管理不科学、转型竞争力不足的困境,对企业充分释放发展潜力形成制约,影响了企业市场空间的扩展。为此,从完善金融服务体系、推动高标准建设、增强财务管理意识和提高技术创新能力着手,提出相应纾解策略,以期为推动民营企业更好发展提供借鉴。

关键词：经济新常态民营企业经营困境纾解策略

委内瑞拉人员精简与“3.16”跨国应急疏散实践

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中国安全生产科学技术 2019年第S02期15卷 61-64页

作者：梁政伟晁阳曹民权中油国际拉美公司委内瑞拉加拉加斯999188 中国石油天然气集团有限公司北京100007

为了实现集团公司"三保"目标要求,通过深入分析当前国际业务面临的严峻社会安全形势,明确了人员精简的现实意义,详细阐述了委内瑞拉人员精简原则和具体实施方法。以"3.16"委内瑞拉应急疏散经验为基础,从选取中转目的地到最终签约包机公... 详细信息

为了实现集团公司"三保"目标要求,通过深入分析当前国际业务面临的严峻社会安全形势,明确了人员精简的现实意义,详细阐述了委内瑞拉人员精简原则和具体实施方法。以"3.16"委内瑞拉应急疏散经验为基础,从选取中转目的地到最终签约包机公司,全面系统地介绍了应急疏散前期准备全流程,形成了控减人员数量的工作方法,为今后海外项目紧急情况下人员精简和应急疏散积累了丰富的经验。

关键词：国际业务委内瑞拉人员精简应急疏散

政府补助时序模式抉择——高新技术行业政府补助、R&D投资与绩效的中介效应

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科技进步与对策 2016年第11期33卷 42-47页

作者：章新蓉梁正伟陈煦江重庆工商大学会计学院重庆工商大学研究生院重庆400067

对中国2007—2014年516家高新技术上市公司面板数据进行时序分组发现,政府补助均能通过R&D投资对企业绩效产生正向中介效应。其中,在"事中补助"模式中本期补助经本期R&D投入对本期企业绩效的总效用最优,但中介效应较差;上期补助经上期R&... 详细信息

对中国2007—2014年516家高新技术上市公司面板数据进行时序分组发现,政府补助均能通过R&D投资对企业绩效产生正向中介效应。其中,在"事中补助"模式中本期补助经本期R&D投入对本期企业绩效的总效用最优,但中介效应较差;上期补助经上期R&D投入对本期企业绩效的总效用稍差,但中介效用最优,因此最符合政府补助的政策导向初衷;而"事前补助"模式总效用和中介效用较差。结论有效论证和解决了政府补助时序模式抉择的争议,也为政府补助模式选择和政策倾向提供了决策参考。

关键词：政府补助时序 R&D投资企业绩效中介效应