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First Asian fossil record of Platydictya (Amblystegiaceae) from the lower Miocene and its paleoenvironmental significance

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Frontiers of Earth Science 2023年第1期17卷 351-360页

作者： Liyan GUO Liang XIAO Ya LI Xiangchuan LI Qin LENG Nan SUN Junfeng GUO Chaofeng FU Jianan WANG Deshuang JI College of Earth Sciences and Resources&Key Laboratory of Western Mineral Resources and Geological Engineering(the Ministry of Education) Chang᾽an UniversityXi᾽an 710054China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Laboratory for terrestrial Environments Bryant UniversitySmithfieldRI 02917USA Shaanxi Key Laboratory of Early Life and Environments&State Key Laboratoty of Continental Dynamics Northwest UniversityXi᾽an 710069China

Mosses form a diverse land plant group in modern vegetation but have rarely showed up in the fossil record compared with vascular plants. Here, we report an extraordinarily-preserved early Miocene moss fossil from the lower Laoliangdi Formation in the Pingzhuang Coal Mine in Chifeng, Inner Mongolia Autonomous Region, northern China. Although lacking rhizoids and most reproductive organs, the well-preserved fossil allows us to assign it to Platydictya cf. jungermannioides (Amblystegiaceae) based upon its detailed gross and micro-morphology. The diagnostic characteristics include a small-sized body with slender stems bearing spirally arranged ovate-lanceolate leaves that lack costae. Leaf margins are mostly partly entire and partly dentate, a few dentate, and rarely completely entire. It represents the first fossil record of Platydictya in Asia. The specific living microenvironment of the extant P. jungermannioides enriched our understanding of the early Miocene environment that was previously based upon vascular plant fossils and sedimentary lithofacies in the area. Our early Miocene Platydictya cf. jungermannioides fossil lived in a warm and humid lush forest with a dense understory that received adequate water supplies.

关键词： moss the Pingzhuang Coal Mine Inner Mongolia Platydictya paleoenvironment

A re-evaluation of the average chain length of lacustrine sedimentary n-alkanes as a paleoproxy on the Qinghai-Tibet Plateau

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Frontiers of Earth Science 2023年第4期17卷 905-919页

作者： Mingda WANG Qin LI Jaime TONEY David HENDERSON Juzhi HOU School of Geography Liaoning Normal UniversityDalian 116029China Alpine Paleoecology and Human Adaptation(ALPHA)group State Key Laboratory of Tibetan Plateau Earth SystemResources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China School of Geographical and Earth Sciences University of GlasgowGlasgow G128QQScotlandUK CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China

Long-chain n-alkanes are one of the most common organic compounds in terrestrial plants and they are well-preserved in various geological archives.n-alkanes are relatively resistant to degradation and thus they can provide high-fidelity records of past vegetation and climate ***,previous studies have shown that the interpretation of n-alkane proxies,such as the average chain length(ACL),is often ambiguous since this proxy depends on more than one *** vegetation and climate could exert controls on the n-alkane ACL,and hence its interpretation requires careful consideration,especially in regions like the Qinghai-Tibet Plateau(QTP)where topography,biome type and moisture source are highly *** further evaluate the influences of vegetation and climate on the ACL in high-elevation lakes,we examined the n-alkane distributions of the surface sediments of 55 lakes across the *** results show that the ACL across a climatic gradient is significantly affected by precipitation,rather than by *** positive correlation between ACL and precipitation may be because of the effect of microbial degradation during ***,we suggest that more caution is needed in the interpretation of ACL data in different regions.

关键词： ACL average chain length n-alkanes leaf wax lake sediments Qinghai-Tibet Plateau

Opportunistic Error Correction for OFDM-Based DVB Systems

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Communications and Network 2013年第4期5卷 344-352页

作者： Xiaoying Shao Cornelis H. Slump Signals and Systems group University of Twente Enschede The Netherlands

DVB-T2 (second generation terrestrial digital video broadcasting) employs LDPC (Low Density Parity Check) codes combined with BCH (Bose-Chaudhuri-Hocquengham) codes, which has a better performance in comparison to convolutional and Reed-Solomon codes used in other OFDM-based DVB systems. However, the current FEC layer in the DVB-T2standard is still not optimal. In this paper, we propose a novel error correction scheme based on fountain codes for OFDM-based DVB systems. The key element in this new scheme is that only packets are processed by the receiver which has encountered high-energy channels. Others are discarded. To achieve a data rate of 9.5 Mbits/s, this new approach has a SNR gain of at least 10 dB with perfect channel knowledge and 11 dB with non-perfect channel knowledge in comparison to the current FEC layer in the DVB-T2standard. With a low-complexity interpolation-based channel estimation algorithm, opportunistic error correction offers us a QEF (Quasi Error Free) quality with a maximum DF (Doppler Frequency) of 40 Hz but the current DVB-T2 FEC layer can only provide a BER of 10?7 quality after BCH decoding with a maximum DF of 20 Hz.

关键词： DVB-T2 LDPC BCH Convolutional Reed-Solomon Codes OFDM Fountain Codes

A Study on the Assessment and Integration of Multi-Source Evapotranspiration Products over the Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第3期41卷 435-448页

作者： Ming CHENG Lei ZHONG Yaoming MA Han MA Yaoxin CHANG Peizhen LI Meilin CHENG Xian WANG Nan GE School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Hefei 230026China Jiangsu Collaborative Innovation Center for Climate Change Nanjing 210023China Frontiers Science Center for Planetary Exploration and Emerging Technologies University of Science and Technology of ChinaHefei 230026China Land-Atmosphere Interaction and its Climatic Effects group State Key Laboratory of Tibetan Plateau Earth SystemResources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China College of Atmospheric Science Lanzhou UniversityLanzhou 730000China National Observation and research Station for Qomolongma Special Atmospheric Processes and Environmental Changes Dingri 858200China Kathmandu Center of research and Education Chinese Academy of SciencesBeijing 100101China China-Pakistan Joint research Center on Earth Sciences Chinese Academy of SciencesIslamabad 45320Pakistan

Evapotranspiration(ET)is a crucial variable in the terrestrial water,carbon,and energy *** present,a large number of multi source ET products *** to sparse observations,however,great challenges exist in the evaluation and integration of ET products in remote and complex areas such as the Tibetan Plateau(TP).In this paper,the applicability of the multiple collocation(MC)method over the TP is evaluated for the first time,and the uncertainty of multisource ET products(based on reanalysis,remote sensing,and land surface models)is further analyzed,which provides a theoretical basis for ET data *** results show that 1)ET uncertainties quantified via the MC method are lower in RS-based ET products(5.95 vs.7.06 mm month^(-1))than in LSM ET products(10.22 vs.17.97 mm month^(-1))and reanalysis ET estimates(7.27 vs.12.26 mm month-1).2)A multisource evapotranspiration(MET)dataset is generated at a monthly temporal scale with a spatial resolution of 0.25°across the TP during *** has better performance than any individual product.3)Based on the fusion product,the total ET amount over the TP and its patterns of spatiotemporal variability are clearly *** annual total ET over the entire TP is approximately 380.60 ***,an increasing trend of 1.59±0.85 mm yr^(-1)over the TP is shown during *** study provides a basis for future studies on water and energy cycles and water resource management over the TP and surrounding regions.

关键词： evapotranspiration data fusion multiple collocation the Tibetan Plateau

Examining Health of Wetlands with Multiple Ecosystem Services as Targets in China’s Coastal Regions

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Chinese Geographical Science 2020年第4期30卷 600-613页

作者： ZHOU Yangming DOU Yuehan YU Xiubo ZHANG Li HUANG Chong WANG Yuyu LI Xiaowei LI He JIA Yifei BAKKER Martha CARSJENS Gerrit Jan ZHOU Yan DUAN Houlang School of Geography and Environment Jiangxi Normal UniversityNanchang 330022China Land Use Planning group Wageningen University and ResearchWageningen 6700HBthe Netherlands Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Key Laboratory for Biodiversity Science and Ecological Engineering Ministry of EducationCollege of Life SciencesBeijing Normal UniversityBeijing 100875China State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of Nature Conservation Beijing Forestry UniversityBeijing 100083China Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai Shandong 264003China College of Biology and Environment Nanjing Forestry UniversityNanjing 210037China

Coastal zones are key interconnectors of terrestrial and marine *** to the degradation and fragmentation of coastal wetlands,there is an urgent need to develop assessment methodology to compare the health of wetland ecosystems at different spatial *** will help efficiently develop and implement protections using easy-to-access ecosystem health *** study aims to understand the spatial distribution of coastal and inland wetland health for China’s coastal regions.A Wetland Health Index(WHI)was developed to provide a basis for policy and decision *** utilization models—Long Term Model,Open Model,Nature Reserve Model,and Protected and Economic Model—were defined in the context of China’s coastal regions to specifically examine wetland *** show that the average WHI score was 63.6 with the range of 44.8–84.3 for 35 National Nature Reserves(NNRs),and the southern NNRs generally performed better than the northern *** wetlands in the southern provinces/municipalities are relatively healthier than their northern *** competent authority has slight influence on WHI scores but duration of conservation establishment does not show a clear *** increasing economic activity,the differences in health conditions(WHI scores)of China’s coastal regions also *** Domestic Product(GDP)or economic intensification does not relate to WHI *** trade-offs between wetland management and economic development could contribute to improve health conditions,conservation and utilization of coastal and inland wetlands.

关键词： Wetland Health Index(WHI) ecosystem services wetland utilization coastal zones

Characterization of the Dominant Bacterial Communities Associated with terrestrial Isopod Species Based on 16S rDNA Analysis by PCR-DGGE

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Open Journal of ecology 2018年第9期8卷 495-509页

作者： Delhoumi Majed Zaabar Wahiba Bouslama Mohamed Fadhel Achouri Mohamed Sghaier Laboratory of Bio-ecology and Evolutionary Systematics Department of Biology Faculty of Sciences of Tunis University of Tunis El Manar Tunis Tunisia

From the marine environment, woodlice gradually colonized terrestrial areas benefiting from the symbiotic relationship with the bacterial community that they host. Indeed, they constitute the only group of Oniscidea suborder that has succeed to accomplish their lives in terrestrial even desert surfaces. Herein they play an important role in the dynamic of ecosystems and the decomposition of litter. So to enhance our understanding of the sea-land transition and other process like decomposition and digestion of detritus, we studied the bacterial community associated with 11 specimens of terrestrial isopods belonging to six species using a Culture independent approach (DGGE). Bands sequencing showed that the cosmopolitan species Porcellionides pruinosus has the most microbial diversity. Screening demonstrated the predominance of Proteobacteria followed by members from Actinobacteria, Firmicutes and Cyanobacteria phyla. In fact we detected some symbionts like Wolbachia, Mycoplasma and Spiroplasma for the first time in a terrestrial isopod species.

关键词： Microbial Community PCR-DGGE terrestrial Isopod Symbiont

Review of the characteristics and graded utilisation of coal gasification slag

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Chinese Journal of Chemical Engineering 2021年第7期34卷 92-106页

作者： Xiaodong Liu Zhengwei Jin Yunhuan Jing Panpan Fan Zhili Qi Weiren Bao Jiancheng Wang Xiaohui Yan Peng Lv Lianping Dong State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China Institute of Coal Chemical Industry Technology National Energy Group Ningxia Coal Industry Co.Ltd.Yinchuan 750411China China Energy Investment group Co. Ltd.Beijing 100011China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China College of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China

The characteristics of the energy structure of rich coal,less oil and less gas,coupling with a high external dependence on oil and natural gas and the emphasis on the efficient and clean utilisation of coal,have brought opportunities for coal chemical ***,with the large-scale popularisation of coal gasification technology,the production and resulting storage of coal gasification slag continue to increase,which not only result in serious environmental pollution and a waste of terrestrial resources,but also seriously affect the sustainable development of coal chemical ***,the treatment of coal gasification slag is extremely *** this paper,the production,composition,morphology,particle size structure and water holding characteristics of coal gasification slag are introduced,and the methods of carbon ash separation of gasification slag,both domestically and abroad,are *** addition,the paper also summarises the research progress on gasification slag in building materials,ecological restoration,residual carbon utilisation and other high-value utilisation,and ultimately puts forward the idea of the comprehensive utilisation of gasification *** large-scale consumption to solve the environmental problems of enterprises and achieve high-value utilisation to increase the economic benefits of enterprises,it is urgent to zealously design a reasonable and comprehensive utilisation technologies with simple operational processes,strong adaptability and economic benefits.

关键词： Coal gasification slag Morphological characteristics Dehydration Separation Comprehensive utilisation

Multi-omics:Powerful accelerator for uncovering plant specialized metabolic pathways:The case of leonurine

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Molecular Plant 2024年第1期17卷 13-15页

作者： Priyanka Gupta Anuj Sharma Dinesh A.Nagegowda Molecular Plant Biology and Biotechnology Lab CSIR-Central Institute of Medicinal and Aromatic PlantsResearch CentreBengaluru 560065India Academy of Scientific and Innovative research Ghaziabad 201002India

As sessile organisms,plants employ a unique adaptive strategy to survive harsh terrestrial environments and defend against or interact with coevolving animals and *** strategy involves expanding their metabolic systems,resulting in the production of plant specialized metabolites(PSMs)or natural ***,PSMs constitute a highly diverse group of compounds based on their common core structure,comprising terpenoids,phenylpropanoids,benzenoids,alkaloids and nitrogen-containing compounds,glucosinolates,indoles and sulfur-containing indole compounds,phenolics,and fatty acid derivatives(Garagounis et al.,2021).

关键词： expanding alkaloids sulfur

Taxonomy,distribution,and contemporary exposure of terrestrial mammals to floods and human pressure across different areas for biodiversity conservation in China

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Integrative Zoology 2024年第3期19卷 458-467页

作者： Roman SHARNUUD Eric I.AMECA MOE Key Laboratory for Biodiversity Science&Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijingChina Climate Change Specialist group Species Survival CommissionInternational Union for Conservation of NatureGlandSwitzerland

A significant research focus is placed on identifying animal species and areas at future risk to human-induced alterations of the environment and long-term changes in climatic ***,the extent to which exposure to extreme climatic events and intense human pressure can increase the risk of harmful impacts on species remains poorly *** on terrestrial mammals in China,one of the world’s megadiverse countries,we investigated patterns of contemporary exposure to floods and human pressures and determined their taxonomic representation and distribution across three major area-based conservation schemes,namely,national nature reserves(NNRs),priority areas for biodiversity conservation(PABCs),and key biodiversity areas(KBAs).Among the 440 species assessed with moderate or high exposure to floods,327(∼75%)also qualified as moderate or high in exposure to intense human *** species mainly belong to the orders Chiroptera,Eulipotyphla,and ***,there were 305,311,and 311 species with moderate or high exposure to flood and intense human pressure represented across NNRs,PABCs,and KBAs,*** findings support the prioritization of KBAs for expansion of site-based protection efforts such as NNRs in China,considering threats to species from exposure to adverse effects from both extreme climate and human pressure.

关键词： conservation floods human pressure mammals taxonomy