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PARTITION OF SEASON BASED ON MULTIELEMENTS AND THE DECADAL change OF SEASON DURATION IN CHINA

Journal of Tropical Meteorology 2019年第3期25卷 385-398页

作者： WANG Zheng ZHI Rong WANG Yu FENG Guo-lin College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000 China Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081 China

Using the multielements similarity measurement method and 1950-2017 NCEP/NCAR gridded daily reanalysis datasets, we analyzed season duration in China during 1950-2016, and we defined the element with maximum absolute sensitivity as the key impact element at each point using the sensitivity analysis method. The decadal change of season duration and its key impact element before and after 1980 were studied. The results indicated obvious meridional and zonal differences in the distribution of season duration for the 67-year average, and that the key impact element has the same distribution characteristics as season duration. In addition, complementary relationships were found between the durations of spring and summer, autumn and winter, and the cold and warm seasons. Among them, the complementary relationship between the durations of spring and summer was strongest and the regions of complementarity were numerous. The complementary regions of autumn and winter durations were found mainly in western China. In the cold and warm seasons, the complementary regions were widespread and the complementary relationship was generally weak. Comparison of the periods before and after 1980 revealed an east-west difference in the interdecadal variation of season duration. Interdecadal variation in spring and summer was found concentrated in northern and western regions, while that in autumn and winter was concentrated in the western region. Areas of significant interdecadal variation of the key elements were found concentrated in northern and western regions,corresponding well to the areas of significant interdecadal variation of season duration.

关键词： multielements similarity measurement method season duration key impact element decadal change

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The change of Land Use/Cover and Characteristics of Landscape Pattern in Arid Areas Oasis： An Application in Jinghe, Xinjiang

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Geo-Spatial Information Science 2010年第3期13卷 174-185页

作者： TASHPOLAT·Tiyip Hsiang-te KUNG Department of Resources and Environment Sciences Xinjiang University Key Laboratory of Oasis Ecology Ministry of Education Department of Earth Sciences Memphis University

This paper uses 3S technology in macroscopic. Combining the integrated technology of ecological quantity analytical method with GIS technology through ArcGIS and Fragstats, the authors study the images of 1972, 1990, 2001, and 2005 and obtained land use data in Jinghe County. Then, the change of land use/cover and landscape pattern had been analyzed in the Jinghe County of Xinjiang. The conclusions were as follows: (1) The trend of LUCC is that the area of oasis expands slowly in nearly 33 years between 1972 to 2005 in Jinghe County. (2) The water area is mainly influenced by Ebinur Lake, so the area expands a little in this period. (3) The area of salinization-land expands at first and reduces later. The area of sand land decreases and the other land class increases, while the probability of transfer is always high. (4) Landscape change is also obvious throughout the decades. Overall, landscape density increases, the largest path index decreases at first and expends later, the weight area index decreases, and the shape of landscape becomes regulated. The nearest distances, the degrees of reunite, and outspread decreases. It shows that the connection of the main path in 1972 is better than 2005, wherein the patch becomes more complex. From the changes of Shannon’s Diversity Index and Shannon’s Evenness Index, we know that the diversity of landscape and the Interspersion Juxtaposition Index increase. The degree of diversity landscape and fragmentation increase also shows that the land uses become more complex. All in all, it is essential to intensify the spatial relationships among landscape elements and to maintain the continuity of landscape ecological process and pattern in the course of area expansion.

关键词： arid area oasis land use/cover change (LUCC) landscape change Jinghe County

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Radiolarian record to paleoecological environment change events over the past 1.2 MaBP in the southern South China Sea

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Chinese Science Bulletin 2002年第17期47卷 1478-1483页

作者： YANG Lihong CHEN Muhong WANG Rujian ZHEN Fan The South China Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China Key Laboratory of Marine Geology Ministry of EducationTongji UniversityShanghai 200092China

This note studies the Radiolarian fossil groups since 1.2 MaBP in ODP leg 184 site 1143, the southern South China Sea (SCS). The result shows that radiolarian abundance experienced a significant variation: before 0.9 MaBP it remained at the extremely low level, but increased with low extent between 0.9-0.65 Ma, which corresponded to the Mid-Pleistocene Transition stage, and it increased rapidly after 0.65 MaBP. During the whole process, the average abundance became higher and higher in each stage, and showed regularly periodic fluctuations. The obvious increase after 0.65 MaBP is inferred to result from the enhanced up-welling in this region, which was induced by the intensified monsoon circulation after the 'Mid-Pleistocene Transition'. An outstanding result of the spectral analyses is that a long oscillation of - 0.2 Ma cycle was found in the records of radiolarian abundance and complex diversity, which corresponds well to the result of other paleoceanographic indexes. This probably indicated a

关键词： radiolarian southern South China Sea distribution environmental change site 1143.

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AN ATTRIBUTION ANALYSIS OF changeS IN POTENTIAL EVAPOTRANSPIRATION IN THE BEIJING-TIANJIN-HEBEI REGION UNDER CLIMATE change

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Journal of Tropical Meteorology 2019年第1期25卷 82-91页

作者： YU Zhan-jiang ZHOU Wei-can ZHANG Xiao Nanjing University of Information Science and Technology Shijiazhuang Meteorological Bureau College of Resources and Environment Shijiazhuang University

Based on the measurements obtained at 64 national meteorological stations in the Beijing-Tianjin-Hebei(BTH) region between 1970 and 2013, the potential evapotranspiration(ET_0) in this region was estimated using the Penman-Monteith equation and its sensitivity to maximum temperature(T_(max)), minimum temperature(T_(min)), wind speed(V_w), net radiation(R_n) and water vapor pressure(P_(wv)) was analyzed, respectively. The results are shown as follows.(1)The climatic elements in the BTH region underwent significant changes in the study period. V_wand R_ndecreased significantly, whereas T_(min), T_(max)and P_(wv)increased considerably.(2) In the BTH region, ET_0 also exhibited a significant decreasing trend, and the sensitivity of ET_0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET_0 was most sensitive to P_(wv)in the fall and winter and R_nin the spring and summer. On the annual scale,ET_0 was most sensitive to P_(wv), followed by R_n, V_w, T_(max)and T_(min). In addition, the sensitivity coefficient of ET_0 with respect to P_(wv)had a negative value for all the areas, indicating that increases in P_(wv) can prevent ET_0 from increasing.(3)The sensitivity of ET_0 to T_(min) and T_(max) was significantly lower than its sensitivity to other climatic elements. However,increases in temperature can lead to changes in P_(wv) and R_n. The temperature should be considered the key intrinsic climatic element that has caused the"evaporation paradox"phenomenon in the BTH region.

关键词： Beijing-Tianjin-Hebei region climate change potential evapotranspiration climatic element sensitivity coefficient

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Animal diversities and characteristics of environmental change revealed by skeletons unearthed at Zhongba Site of Chongqing City,China

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Chinese Science Bulletin 2008年第S1期53卷 74-86页

作者： ZHU Cheng MA ChunMei OUYANG Jie LI ZhongXuan YIN Qian SUN ZhiBin HUANG YunPing R.K.FLAD LI Lan LI YuMei School of Geographic and Oceanographic Sciences of Nanjing University Nanjing 210093China Cultural Relic and Archaeology Research Institute of Sichuan Province Chengdu 610041China Faculty of Archaeology and Museology Peking UniversityBeijing 100871China Department of Anthropology Peabody MuseumHarvard UniversityCambridgeMA 02138USA Graduate University of Chinese Academy of Sciences Beijing 100049China

Nearly 200000 animal skeletons are unearthed in the Unit T0202 from Zhongba Site of Zhongxian *** to the analysis of 129165 specimens,these skeletons may be classified into 5 kinds, namely,Mammalia,Osteichthys,Aves,Amphibian and Reptilia,which belong to 13 orders,28 families and 42 *** this paper,based on archeological dating and AMS 14 C data,through statistically analyzing the unearthed skeletons and studying the change of the smallest individual numbers,these research results detected the following:1)In almost all the time of 2370―200 BC,in Zhongba region, some animals distributed widely,such as Muntiacus sp,Elaphodus cephalophus and Muntiacus sp. inhabiting in glade and grassland,Scrofa *** Canis familiaris raised by the ancient people,rodentia rabbit and Rattus rattus,which suggested that a fairly good ecological environment of forest and grassland was preserved at that period and the predecessors began to raise domestic animals from 1750 to 1000 BC,which has lasted until today.2)Rhinoceros only lived during 2000―1750 BC,1000― 700 BC and 700―500 BC,which indicates that the ecological environment of grassland and wetland might be better in these phases.3)Macaca *** Ursus arctos appeared only after 1750―1000 BC, which may show that the forest condition is better for animals to live during 1750―200 BC.4)The smallest individual numbers of Bublus sp.,bos *** otters emerged during about 2370―1750 BC, which perhaps infers that water area during the early period was wider than that of the late period.5) Since skeletons of rhinoceros are discovered in strata of Zhongba Site during 2000―1750 BC and 1000―500 BC,according to the climate and ecology environment which rhinoceros live in now,the average annual temperature and precipitation during 2000―1750 BC and 1000―500 BC are supposed to be probably higher than that of *** Zhu Kezhen considered that the first low temperature period in the past 5000 years of China was between 1100 BC a

关键词： Zhongba Site animal skeletons animal diversity climate and ecological environment change 2370 BC—200 BC

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THE RELATIONSHIP BETWEEN ENVIRONMENT change AND SE MONSOON STRENGTH, DAIHAI LAKE, INNER MONGOLIA

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Science China Chemistry 1992年第6期35卷 722-734页

作者：王苏民冯敏 Nanjing Lake Sediment and Limnology Lab Loess and Quaternary Geology Lab Academia Sinica Nanjing 210008 PRC

Daihai Lake, located in NW margin of SE monsoon region, belongs to the sensitive area for climatic fluctuation. The analysis of continuous sedimentary column with an age of 100 ka indicates that there exists the different quasiperiodicity in time scales for monsoon shift. The climatic fluctuation in the Daihai Basin shows all along the alternation of cold and dry with a warm and wet climatic pattern, suggesting that the strength and drift of SE monsoon play a controllable role in the climatic change.

关键词： climatic change lacustrine sediment monsoon.

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Long-term protection effects of national reserve to forest vegetation in 4 decades: biodiversity change analysis of major forest types in Changbai Mountain Nature Reserve, China

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Science China(Life Sciences) 2008年第10期51卷 948-958页

作者： BAI Fan1, SANG WeiGuo1, LI GuangQi1, LIU RuiGang1, CHEN LingZhi1 & WANG Kun2 1 State Key Laboratory of Vegetation and Environment change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China 2 Nature Reserve Bureau of Changbaishan, Jilin 210011, China State Key Laboratory of Vegetation and Environment change Institute of Botany Chinese Academy of Sciences Beijing China Nature Reserve Bureau of Changbaishan Jilin China

The Changbai Mountain Nature Reserve (CNR) was established in 1960 to protect the virgin Korean pine mixed hardwood forest, a typical temperate forest of northeast China. We conducted systematic stud- ies of vascular diversity patterns on the north slope of the CNR mountainside forests (800-1700 m a.s.l.) in 1963 and 2006 respectively. The aim of this comparison is to assess the long-term effects of the protection on plant biodiversity of CNR during the interval 43 years. The research was carried out in three types of forests: mixed coniferous and broad-leaved forest (MCBF), mixed coniferous forest (MCF), and sub-alpine coniferous forest (SCF), characterized by different dominant species. The alpha diversity indicted by species richness and the Shannon-Wiener index were found different in the same elevations and forest types during the 43-year interval. The floral composition and the diversity of vascular species were generally similar along altitudinal gradients before and after the 43-year interval, but some substantial changes were evident with the altitude gradient. In the tree layers, the dominant species in 2006 were similar to those of 1963, though diversity declined with altitude. The indices in the three forest types did not differ significantly between 1963 and 2006, and these values even increased in the MCBF and MCF from 1963 to 2006. However, originally dominant species, P. koraiensis for ex- ample, tended to decline, while the proportion of broad-leaved trees increased, and the species turn- over in the succession layers trended to shift to higher altitudes. The diversity pattern of the under canopy fluctuated along the altitudinal gradient due to micro-environmental variations. Comparison of the alpha diversity in the three forests shows that the diversity of the shrub and herb layer decreased with time. During the process of survey, we also found some rare and medicinal species disappeared. Analysis indicates that the changes of the diversity pattern

关键词： plant species diversity climate change forest community human activity Changbai Mountain

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CLIMATIC change SINCE LITTLE ICE AGE RECORDED BY DUNDE ICE CAP

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Science China Chemistry 1991年第6期34卷 760-767页

作者：姚檀栋谢自楚武筱舲 L.G.THOMPSON Lanzhou Institute of Glaciology and Geocryology. Academia Sinica. Lanzhou 730000 PRC Byrd Polar Research Center The Ohio State University USA.

The climatic change since the Little Ice Age recorded in the Dunde Ice Cap is presentedin this paper. There have been three cold periods and three warm periods since *** them, the coldest one was in the 17th century. Many evidences verified the three coldand warm variations recorded in the Dundc Ice Cap. But it was found from the comparison between the Dunde Icc Cap climatic record and thewinter temperature record in Shanghai that there was a temporal dfference in climatic changebetween East China and West China. The general trend is that the cooling and warmingprocesses in West China were earlier than that in East China. In the Dunde Ice Cap, it isnow in an anomalous warm period, while it is not as warm as in Dunde Ice Cap recordaccording to the winter temperature in Shanghai. In addition to the possible cause of temporaldifference in climatic change between West China and East China, another possible cause isthat the greenhouse effect of CO_2 may already be recognizable in the Dunde Ice Cap arealocated in Western China in land of the middle latitude.

关键词： Dunde Ice Cap Little Iee Age climatic record difference in climatic change between West China and East China

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change in Childcare Policy and Defamilialization

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学术界 2017年第11期 257-267页

作者： Mihyang Choi Sungkyunkwan University

This study explores childcare policy change in South Korea by employing the gradual institutional change model and in relation to the concept of defamilialization.T his study measured the degree of defamilialization quantitatively using the data of Childcare Statistics between 2001-2016 and conducted hierarchical cluster *** analysis results showed that the trajectories of childcare policy in South Korea could be divided into three clusters-2001-2006 for the first cluster,2007-2012 for the second cluster,and2013-2016 for the third cluster-and there were two changes-conversion and *** policy in South Korea has taken the path of familialization,market defamilialization,and active familialization.

关键词： childcare policy policy change defamilialization South Korea

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Reliability Modelling and Prediction Method for Phase change Memory Using Optimal Pulse Conditions

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Journal of Shanghai Jiaotong university(Science) 2020年第1期25卷 1-9页

作者： YAN Shuai CAI Daolin CHEN Yifeng XUE Yuan LIU Yuanguang WU Lei SONG Zhitang State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China University of Chinese Academy of Sciences Beijing 100049China

Phase change memory(PCM)has reached the level of mass *** first step in mass production is determining the proper pulse conditions of high-resistance(HR)and low-resistance(LR)states to realize the best performance of PCM chips on the basis of longer endurance ***,due to the neglect of each of the relations as well as the square term of each relationship for pulse conditions,the standard screening method for pulse conditions cannot accurately det ermine the optimal pulse conditions.A new statistical prediction method based on regression analysis is presented in this *** method can model and predict the optimal pulse conditions of PCM chips on the basis of longer endurance *** the method,the parameter est imates,model equations and surface plot are genera ted by the least-mean-square(LMS)method for the regression analysis;the prediction model is established by monitoring the distributions of the resistance values collected from a 4 Kbit block of the 4 Mbit PCM test chips in 40 nm complementary metal oxide semiconductor(CMOS)process.

关键词： phase change memory(PCM) prediction model regression analysis pulse conditions

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