Visualization of Climate Change and Economic Research Hotspots:Integrating Cited References and Burst Keywords   总被引：1，自引：1，他引：0  

Ning Li  Li Liu  Zhengtao Zhang  Jieling Feng  Xi Chen  Kou Bai 《地球科学进展》2018,33(8):865-873

The study of the economic impact of climate change has received extensive attention from governments and scholars around the world. This paper based on 14 796 literatures that related to climate change and economic from the core database of Web of Science. Integrating the method of co-citation network and burst keywords co-occurrence network to analyze the temporal and spatial changes of research hotspots on climate change and economic impact. The results show that the global literature's number keep a exponential growth trend, rapidly after 2007. Before 2007, the research hotspots primarily centered on the climate change attribution analysis (increased CO₂ emissions from fossil fuels, land use changes, etc.), the impact on natural ecosystems (agricultural production, food security, Arctic ice caps, coastal zones, etc.) and socio-economic System (human health, energy, industry, etc.), and the assessment of economic impac and then focused on the future scenarios of climate change and CO₂ abatement and how to adapt and mitigate the climate change. After 2007, with the introduction of IPCC AR4 and Stern report, further strengthened the research on cost-effective assessment of climate change impact, vulnerability, bioenergy and so on. The research hotspots focus on economics of climate change and trade. In space, the literatures of research hotspots were mainly come from the United States, Canada, Western European countries (UK, France, Germany, Italy, Netherlands), Australia and China.  相似文献   

Model test of stratum failure and pore pressure variation induced by THF hydrate dissociation     

Tao Liu  Lei Zhou  Hai-lei Kou  Mei-xin Zhang 《Marine Georesources & Geotechnology》2013,31(5):539-546

ABSTRACT

A model test program for studying soil stratum failure and pore pressure variation during tetrahydrofuran (THF) hydrate dissociation considering the effects of heating and drainage conditions is presented in this paper. The temperature and pore pressures are recorded during heating. Test results show that the THF hydrate would dissociate to be liquid and then gas when heating. Once pore pressure generated by the flow of released gas/water exceeded the strength of over layer, the layered fractures and soil-gas/water mixture outburst would occur. The high heating temperature and low permeability of over layer both cause excess pore pressure generation and more serious stratum failures.  相似文献   

Molecular phylogeny of Parapenaeopsis Alcock, 1901 (Decapoda: Penaeidae) based on Chinese materials and 16S rDNA and COI sequence     

LI Xinzheng  XU Yan  and KOU Qi 《中国海洋大学学报(英文版)》2014,13(1):104-114

The phylogenetic relationship among Chinese Parapenaeopsis species was studied by comparing 16S rDNA and COI gene sequence. The results showed that Parapenaeopsis hardwickii (Miers, 1878) and P. cultrirostris Alcock, 1906 identified from Chinese samples were the same species. Parapenaeopsis cornuta (Kishinouye, 1900), P. incisa Liu and Wang, 1987, and P. sinica Liu and Wang, 1987 were different species. However, their systematic relationship were closer than those of other species, and they formed an advanced branch in the phylogenetic trees. Additionally, the systematic position of P. hardwickii (Miers, 1878), P. hungerfordi Alcock, 1905, and P. tenella (Bate, 1888) were not stable in the phylogenetic trees. More genetic markers such as 18S rDNA and 28S rDNA were supposed to be used to confirm the phylogenic relationship of Parapenaeopsis species.  相似文献   

In-situ Measurements of Cutter Forces on Boring Machine at Äspö Hard Rock Laboratory Part II. Characteristics of Cutter Forces and Examination of Cracks Generated     

Z. X. Zhang  S. Q. Kou  P.-A. Lindqvist 《Rock Mechanics and Rock Engineering》2003,36(1):63-83

Summary By means of spectral analysis, the measured normal forces, tangential forces, and side forces acting on two button cutters on the boring machine in ?sp? Hard Rock Laboratory were analysed and the basic characteristics of the cutter forces were determined. After the measurements of the cutter forces, some rock core samples were taken from the bottom and the wall of the test borehole. These samples were cut, polished, and examined by means of a Scanning Electron Microscope (SEM). The lengths of the major cracks in the rock samples were measured, and a relation between the length of the median cracks and the relevant cutter forces was investigated. Received October 5, 2001; accepted June 25, 2002; Published online November 19, 2002  相似文献   

Accounting for CO<Subscript>2</Subscript> variability over East Asia with a regional joint inversion system and its preliminary evaluation     

Xingxia Kou  Xiangjun Tian  Meigen Zhang  Zhen Peng  Xiaoling Zhang 《Acta Meteorologica Sinica》2017,31(5):834-851

A regional surface carbon dioxide (CO₂) flux inversion system, the Tan-Tracker-Region, was developed by incorporating an assimilation scheme into the Community Multiscale Air Quality (CMAQ) regional chemical transport model to resolve fine-scale CO₂ variability over East Asia. The proper orthogonal decomposition-based ensemble four-dimensional variational data assimilation approach (POD-4DVar) is the core algorithm for the joint assimilation framework, and simultaneous assimilations of CO₂ concentrations and surface CO₂ fluxes are applied to help reduce the uncertainty in initial CO₂ concentrations. A persistence dynamical model was developed to describe the evolution of the surface CO₂ fluxes and help avoid the “signal-to-noise” problem; thus, CO₂ fluxes could be estimated as a whole at the model grid scale, with better use of observation information. The performance of the regional inversion system was evaluated through a group of single-observation-based observing system simulation experiments (OSSEs). The results of the experiments suggest that a reliable performance of Tan-Tracker-Region is dependent on certain assimilation parameter choices, for example, an optimized window length of approximately 3 h, an ensemble size of approximately 100, and a covariance localization radius of approximately 320 km. This is probably due to the strong diurnal variation and spatial heterogeneity in the fine-scale CMAQ simulation, which could affect the performance of the regional inversion system. In addition, because all observations can be artificially obtained in OSSEs, the performance of Tan-Tracker-Region was further evaluated through different densities of the artificial observation network in different CO₂ flux situations. The results indicate that more observation sites would be useful to systematically improve the estimation of CO₂ concentration and flux in large areas over the model domain. The work presented here forms a foundation for future research in which a thorough estimation of CO₂ flux variability over East Asia could be performed with the regional inversion system.  相似文献   

气旋快速发展过程中潜热释放重要性的位涡反演诊断   总被引：4，自引：1，他引：3  

周毅  寇正 《气象科学》1998,18(4):355-360

本文分析了一次爆发性气旋过程中的位涡演变特征,揭示了凝结潜热释放对气旋人上工位涡柱形成所起的作用;通过数值求解位涡反演诊断方程定量诊断出气旋爆发性发展阶段,凝结潜热释放对低层降压和气旋式环流增强的重要影响。  相似文献   

霜害及其预防     

郭晓岚 《气象学报》1941,(Z1)

(一)霜之生成及霜害霜生成时,温度必在冰点以下。在春初作物之嫩芽初放或秋末瓜果将熟时,一遇冰点以下之温度,即易萎折,虽无霜生成,其所生之害亦不稍减。故当春初秋末时,如温度低降至能损及作物,即不见霜,亦称为霜。当温度在零度以下,-2℃以上时,仅能捐及作物之新芽,称为轻霜;如温度在-2℃以下,则并坚老之枝叶亦能摧毀之,故称为杀霜。吾人所论之霜害,仅限于在植物生长期中者,即春初之晚霜及秋末之早霜。此时霜发现之次数虽不多,但与农业之关系甚大。如以天气状况为标准,则霜可分为二大类:  相似文献   

应用遥感技术进行森林资源监测方法的研究   总被引：1，自引：0，他引：1  

寇文正  肖燕宇  张瑞玺 《遥感学报》1990,(2)

森林资源有较强的动态性,监测技术的改进具有重要的生产意义。采用遥感技术,地理信息系统技术与森林连续清查技术相结合的方法实施森林资源监测具有极大的潜力。通过在松江河进行的研究,证明了这种方法的可行性和优越性。 文章探讨了使用新方法的关键技术环节,提供了实施监测的实际结果,指出了在我国北方国有林区推广的前景。与传统方法相比,新方法提供了图面资料,减少地面工作量50％,降低经费20％。  相似文献   

Designation of a new genus <Emphasis Type="Italic">Bathymenes</Emphasis> for the deep-sea pontoniine shrimps of the ‘<Emphasis Type="Italic">Periclimenes alcocki</Emphasis> species group’ (Decapoda,Caridea, Palaemonidae), with a checklist of the species assigned to the genus     

寇琦  李新正 《中国海洋湖沼学报》2016,34(1):170-176

A new genus of the deep-sea pontoniine shrimps, Bathymenes gen. nov., is established for the ‘Periclimenes alcocki species group’ of the genus Periclimenes Costa, 1844. The new genus is distinguished from other genera of the Pontoniinae by a combination of characters: the posteriormost dorsal rostral tooth remote from other teeth, situated in the epigastric position, cornea usually reduced, the propodus of second pereiopods covered with fine granules, the dactylus of the major second chela being generally flanged, the ambulatory pereiopods with the dactyli being biunguiculate and telson with more than two pairs of dorsolateral spines. The genus is mainly distributed in the tropical to warm-temperate Indo-West Pacific waters at depths greater than 200 m. Fifteen species previously recognized as belonging to the ‘P. a lcocki species group’ are now placed in Bathymenes gen. nov. A key for their identification and a checklist of congeneric species are provided.  相似文献   

Multi-scale heterogeneity of soil moisture following snow thawing in <Emphasis Type="Italic">Haloxylon ammodendron</Emphasis> shrubland     

Li Jun  Zhao ChenYi  Zhu Hong  Wang Feng  Wang LiJuan  Kou SiYong 《中国科学D辑(英文版)》2007,50(1):49-55

Spatial variation of soil moisture after snow thawing in South Gurbantunggut was quantitatively studied using ANOVA and geostatistics at various scales. The results show that the soil moisture heterogeneity varies along with spatial scales. At the shrub individual scale, there is a gradient in soil moisture from shrub-canopied area to canopy margin and to the interspaces between shrubs. At the community scale, soil moisture is highly autocorrelated and the semivariogram is fitted as spherical model, with an 89.6% structural variance and a range of 4.02 m. In addition, Kringing map indicates that the soil moisture distribution pattern after snow thawing is highly consistent with the shrub patch pattern. At the typical inter-dune transect scale, soil moisture presents a pattern of high value at inter-dune depression and low value at dune, and this variation is fitted as Gaussian model with a structural variance of 95.8% and a range of 66.16 m. The range is comparable with the scale of topography zoning, suggesting that the topography pattern controls the pattern of snowmelt at this scale. The evidence indicates that the heterogeneity of soil moisture at various scales is controlled by various land surface processes after snow thawing. For Gurbantunggut Desert, the spatial heterogeneity of snowmelt at various scales is ecologically valuable, because it promotes the utilization efficiency of the snowmelt for the desert vegetation.  相似文献