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Permian–Triassic Climatic and Environmental Extremes and biotic Response (IGCP 630:2014–2018):Goals and Achievements

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Acta Geologica Sinica(English Edition) 2019年第3期93卷 780-782页

作者： CHEN Zhongqiang GUO Zhen State Key Laboratory of Biogeology & Environmental Geology China University of Geosciences

IGCP 630,with its full title of"Permian-Triassic(P-Tr)climatic and environmental extremes and biotic response",is an International Geoscience Program project sponsored by the United Nation Educational,Scientific&Cultural Organization(UNESCO)and International Union of Geological Sciences(IUGS).This project was approved in 2014 and ended in 2018,and has applied for one-year extension in *** 630 consists of 150 geoscientists across multidisciplinary geosciences from 27 countries around the world.

关键词： Permian-Triassic Climatic Environmental Extremes biotic Response

Principal aspects of the Ordovician biotic radiation

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Science China Earth Sciences 2010年第3期53卷 382-394页

作者： ZHANG YuanDong,ZHAN RenBin,FAN JunXuan,CHENG JunFeng & LIU Xiao LPS, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 1. LPS Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Ordovician radiation is among the major bioevents in earth history that have drawn great attention from geologists all over the world, and there have been hundreds of publications treating various aspects of this radiation. The study of the event involves a broad spectrum of research fields and concerns many scientific questions. Many opinions and hypotheses have been proposed on the triggering and controlling factors of the radiation. Herein the authors critically review the study of the Ordovician radiation and dissect four principal aspects by synthesizing the studies over the past years: (1) relationships of the radiation to fossil clades, ecotypes, and environments, such as water depth, latitude, and climate; (2) the ecological structure and food webs of Ordovician marine organisms; (3) fossil records and true biodiversities; and (4) likely triggering and controlling factors of the Ordovician radiation. The authors also recommend approaches to furthering studies of these aspects.

关键词： Ordovician biotic radiation guild food web fossil record mechanism

Abiotic and biotic drivers of species diversity in understory layers of cold temperate coniferous forests in North China

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Journal of Forestry Research 2019年第6期30卷 2213-2225页

作者： Hui Wang Mengtao Zhang Hongwei Nan College of Forestry Shanxi Agricultural University

Understory plants are important components of forest ecosystems and play a crucial role in regulating community structures,function realization,and community ***,little is known about how abiotic and biotic drivers affect the diversity of understory species in cold temperate coniferous forests in the semiarid climate region of North *** hypothesized that(1)topographic factors are important environmental factors affecting the distribution and variation of understory strata,and(2)different understory strata respond differently to environmental factors;shrubs may be significantly affected by the overstory stratum,and herbs may be more affected by surface soil *** test these hypotheses,we used the boosted regression tree method to analyze abiotic and biotic environmental factors that influence understory species diversity,using data from 280 subplots across 56 sites in cold temperate coniferous forests of North *** and slope aspect were the dominant and indirect abiotic drivers affecting understory species diversity,and individual tree size inequality(DBH variation)was the dominant biotic driver of understory species diversity;soil water content was the main edaphic factors affecting herb ***,slope aspect,and DBH variation accounted for 36.4,14.5,and 12.1%,respectively,of shrub stratum *** diversity decreased with elevation within the range of altitude of this study,but increased with DBH variation;shrub diversity was highest on north-oriented *** strongest factor affecting herb stratum species diversity was slope aspect,accounting for 25.9%of the diversity,followed by elevation(15.7%),slope(12.2%),and soil water content(10.3%).The highest herb diversity was found on southeast-oriented slopes and the lowest on northeast-oriented slopes;herb diversity decreased with elevation and soil water content,but increased with *** results of the study provide a reference for scientific management and b

关键词： Abiotic and biotic drivers Cold temperate coniferous forests North China Semi-arid region Understory species diversity

Emerging Roles of Sphingolipid Signaling in Plant Response to biotic and Abiotic Stresses

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Molecular Plant 2018年第11期11卷 1328-1343页

作者： Usman Ali Hehuan Li Xuemin Wang Liang Guo National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China Department of Biology University of MissouriSt.LouisMO 63121USA Donald Danforth Plant Science Center St.LouisMO 63132USA

Plant sphingolipids are not only structural components of the plasma membrane and other endomembrane systems but also act as signaling molecules during biotic and abiotic ***,the roles of sphingolipids in plant signal transduction in response to environmental cues are yet to be investigated in detail. In this review,we discuss the signaling roles of sphingolipid metabolites with a focus on plant *** also mention some microbial sphingolipids that initiate signals during their interaction with plants, because of the limited literatures on their plant *** equilibrium of nonphosphorylated and phosphorylated sphingolipid species determine the destiny of plant cells,whereas molecular connections among the enzymes responsible for this equilibrium in a coordinated signaling network are poorly understood.A mechanistic link between the phytohormone-sphingolipid interplay has also not yet been fully understood and many key participants involved in this complex interaction operating under stress conditions await to be *** research is needed to fill these gaps and to better understand the signal pathways of plant sphingolipids and their interplay with other signals in response to environmental stresses.

关键词： sphingolipids long-chain bases sphingolipid signaling biotic stress abiotic stress

Field evaluation of durum wheat landraces for prevailing abiotic and biotic stresses in highland rainfed regions of Iran

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The Crop Journal 2015年第5期3卷 423-433页

作者： Reza Mohammadi Behzad Sadeghzadeh Hasan Ahmadi Nowzar Bahrami Ahmed Amri Dryland Agricultural Research Institute (DARI) Center of Agricultural Research and Natural Resources International Center for Agricultural Research in the Dry Areas (ICARDA)

biotic and abiotic stresses are major limiting factors for high crop productivity worldwide. A landrace collection consisting of 380 durum wheat(Triticum turgidum L. var. durum) entries originating in several countries along with four check varieties were evaluated for biotic stresses:yellow rust(Puccinia striiformis Westendorf f. sp. tritici) and wheat stem sawfly(WSS) Cephus cinctus Norton(Hymenoptera: Cephidae), and abiotic stresses: cold and drought. The main objectives were to(i) quantify phenotypic diversity and identify variation in the durum wheat landraces for the different stresses and(ii) characterize the agronomic profiles of landraces in reaction to the stresses. Significant changes in reactions of landraces to stresses were *** resistant to each stress were identified and agronomically *** reduction due to the stresses varied from 11.4%(yellow rust) to 21.6%(cold stress) for 1000-kernel weight(TKW) and from 19.9(yellow rust) to 91.9%(cold stress) for grain yield. Landraces from Asia and Europe showed enhanced genetic potential for both grain yield and cold tolerance under highland rainfed conditions of Iran. The findings showed that TKW and yield productivity could be used to assess the response of durum wheat landraces to different stresses. In conclusion, landraces showed high levels of resistance to both biotic and abiotic stresses, and selected landraces can serve in durum wheat breeding for adaptation to cold and drought-prone environments.

关键词： Durum wheat Landraces biotic and abiotic stresses

biotic Stress Induced Biochemical and Isozyme Variations in Ginger and Tomato by <i>Ralstonia solanacearum</i>

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American Journal of Plant Sciences 2013年第8期4卷 1601-1610页

作者： Sasidharan Sreedevi Kulangara Nanu Remani Sailas Benjamin Envi- ronmental Studies Division Centre for Water Resources Development and Management (CWRDM) Calicut India. Enzyme Technology Laboratory Biotechnology Division Department of Botany University of Calicut Malappuram India

This unique study evaluates the effects of Ralstonia solanacearum (Rs) induced biotic stress in two cultivars, Zingiber officinale (ginger) and Lycopersicon esculentum (tomato). They were grown in pots and hydroponic systems with controls;to induce biotic stress, about 8 × 104 colony forming units of Rs suspension was injected into the healthy test plants. Upon induction of Rs stress, highly significant (p 0.01) biochemical changes (%) were noticed in respect to controls: carbohydrate content was generally high in both plants;while they showed decreased starch and protein contents;phenolics showed a swing of decrease or increase between pot and hydroponic systems;and all plants in general showed higher (3-6 fold) proline content upon induction of biotic stress. Regarding oxidative stress isozymes (OSE), superoxide dismutase (EC 1.***.1.1) isozymes were normally 3, but treated hydroponics had 4 with comparable relative mobility values;peroxidase (EC 1.***.1.7) isozymes were generally 2, except for treated hydroponic tomato. Briefly, Rs induced biotic stress caused wilt symptoms in ginger, but did not affect tomato though its biochemical and OSE patterns especially in those grown as hydroponics were elicited to significantly higher levels.

关键词： biotic Stress Hydroponics Stress Enzymes R. solanacearum L. esculentum Z. officinale

The Roles of biotic Interactions and Environmental Factors on Multispecies Dynamics

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Open Journal of Ecology 2019年第10期9卷 426-442页

作者： Ojonubah James Omaiye Mohd Hafiz Mohd School of Mathematical Sciences Universiti Sains Malaysia Gelugor Malaysia

The distributions of species in their habitats are constantly changing. This phenomenon is thought to be determined by species’ environmental tolerance and biotic interactions for limited resources and space. Consequently, predicting the future distribution of species is a major challenge in ecology. To address this problem, we use mathematical model to study the combined effects of biotic interactions (e.g. competition) and environmental factors on multiple species community assembly in a heterogenous environment. To gain insights into the dynamics of this ecological system, we perform both analytical and numerical analyses of the range margins of the species. We observe that the range margins of the species can be influenced by biotic interactions combined with environmental factors. Depending on the strength of biotic interactions, our model exhibits coexistence of species and priority effects;mediated by weak and intense biotic interactions respectively. We also show the existence of bifurcation points (i.e. the threshold values of competition coefficient) which lead to the presence—absence of different species. Thus, we suggest that adequate knowledge of biotic interactions and changes in the environments is important for effective maintenance of biodiversity and conservation management.

关键词： Abiotic Environments biotic Interactions Coexistence Priority Effects

Versatile Potentiality of Silicon in Mitigation of biotic and Abiotic Stresses in Plants: A Review

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American Journal of Plant Sciences 2018年第7期9卷 1433-1454页

作者： Paulin Seal Prabal Das Asok K. Biswas Plant Physiology and Biochemistry Laboratory Centre for Advanced Study Department of Botany University of Calcutta Kolkata India

The “quasi-essential element” silicon (Si) is not considered indispensable for plant growth and its accumulation varies between species largely due to differential uptake phenomena. Silicon uptake and distribution is a complex process involving the participation of three transporters (Lsi1, Lsi2 and Lsi6) and is beneficial during recovery from multiple stresses. This review focuses on the pivotal role of silicon in counteracting several biotic and abiotic stresses including nutrient imbalances, physical stresses together with uptake, transport of this metalloid in a wide variety of dicot and monocot species. The knowledge on the beneficial effects of silicon and possible Si-induced mechanisms of minimizing stress has been discussed. Accumulation of silicon beneath the cuticles fortifies the cell wall against pathogen attack. Si-induced reduction of heavy metal uptake, root-shoot translocation, chelation, complexation, upregulation of antioxidative defense responses and regulation of gene expression are the mechanisms involved in alleviation of heavy metal toxicity in plants. Silicon further improves growth and physiological attributes under salt and drought stress. Effective use of silicon in agronomy can be an alternative to the prevalent practice of traditional fertilizers for maintaining sustainable productivity. Therefore, soil nutrition with fertilizers containing plant-available silicon may be considered a cost-effective way to shield plant from various stresses, improve plant growth as well as yield and attain sustainable cultivation worldwide.

关键词： Abiotic Stress Alleviation biotic Stress Silicon Silicon Transporter

The Early Triassic Helongshan Formation in Anhui,China:Record of the Triassic biotic Recovery in the Lower Yangtze Region

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地学前缘 2009年第S1期16卷 254-254页

作者： Liwei Zhang~(1,2),Zhihai Jia~3,Fumei Yang~1,Jinlong Xu~1 1.School of Resources and Environmental Engineering,Hefei University of Technology,Hefei 230009,China. 2.Institute of Resources and Environment,Henan Polytechnic University,Jiaozuo 454000,China 3.School of Chemical and Biomolecular Engineering,University of Sydney,Sydney NSW2006,Australia

The Lower Triassic is well outcropped in central and southern Anhui Province,East China,and it consists of the Yinkong,Helongshan and Nanlinghu Formations in an ascending *** Helongshan Formation belonging to the Smithian has been well studied in this project because of the typical sedimentary features and different fossil types which are not similar to the lower Yinkeng Formation or

关键词： sedimentary characteristics biotic recovery Early Triassic Helongshan Formation