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| 1 | Geomorphological and environmental evolution in the upper reaches of the Yellow River during the late Cenozoic显示文摘Studies of the geomorphology and stratigraphy in the upper reaches of the Yellow River during the late Cenozoic demonstrate that the period of 30 - 3.4 Ma is characterized by a relatively stable tectonic setting, a persistently hot climate and a wide distribution of inland basins. This long-term stable environment resulted in a planation surface, the main surface on the Qinghai-Xizang (Qingzang) Plateau, on which red earth crust and karst arc formed. Since 3.4 Ma, the Qingzang Plateau was 'uplifted as a whole massif, accompanied by the dissection and disintegration of the main surface, termination of deposition and deformation of stratigraphy in red basins, increasing relief and commencing accumulation of inland molasse formation mainly of conglomerate. Subsequent strong uplift of the Qingzang Plateau at 2.5 Ma and 1.7-1.66 Ma led to cormation of the basic geomorphological configuration of the Qingzang Plateau and occurrence of the Yellow River. These three strong uplifts of the Qingzang Plateau | 李吉均 方小敏 马海州 朱俊杰 潘保田 陈怀录 | 1996 | Science China Earth Sciences1996，39，4： | 53 |
| 2 | Geospatial-temporal analysis of land-use changes in the Yellow River Delta during the last 40 years显示文摘Comprehensive study on land-use change of spatial pattern and temporal process is the key component in land use/land cover changes (LUCC) study nowadays. According to the theories and methods of Geo-information Tupu (Carto-methodology in Geo-information, CMGI) for geospatial and temporal analysis and integration models of spatial pattern and temporal processes in GIS, the paper puts forward Tupu methodology of land-use change and names the basic synthetic unit of spatial-temporal information Tupu unit. Tupu unit is the synthetic unit for geospatial-temporal analysis, which is synthesized by “space·attribute·process”features and composed of relatively homogeneous geographic unit and temporal unit. Based on the spatial features of 4 stages of land-use change in 1956, 1984, 1991, and 1996, a series of Tupu on land-use change in the Yellow River Delta (YRD) are created and studied in the paper, which includes 3 temporal units of spatial-temporal Tupu, process Tupu of land-use changes during the last 40 years, and reconstructions of a series of “arisen”Tupu, “arisen”process Tupu and pattern Tupu on land-use changes in the last 40 years by remapping tables of a reclassifying system. There are 3 methods of Tupu analysis on land-use change that are used to disclose change processes of land-use spatial conversion in YRD, such as spatial query and statistics, order of Tupu units by area and land-use conversion matrixes. In order to reveal the spatial pattern of land-use change processes, we analyze spatial-temporal changes of each Tupu above in various temporal units and spatial difference of pattern Tupu in the last 40 years by dynamic Tupu units. Tupu analysis on regional land-use is a promising trial on the comprehensive research of “spatial pattern of dynamic process”and “temporal process of spatial pattern”in LUCC research. The geo-information Tupu methodology would be a powerful and efficient tool on integrated studies of spatial pattern and temporal process in geoscience. | YE Qinghua1,3,4,LIU Gaohuan2,TIAN Guoliang1,CHEN Shenliang3,HUANG Chong2,CHEN Shupeng1,2,LIU Qingshen2,CHANG Jun2 & SHI Yanan2 1.State Key Laboratory of Remote Sensing Science,Institute of Remote Sensing Applications(IRSA),Chinese Academy of Science(CAS),Beijing 100101,China 2.Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China 3.State Key Laboratory of Estuarine and Coastal Research,East China Normal University,Shanghai 200062,China 4.Institute of Tibetan Plateau Research(ITPR),CAS,Beijing 100085,China Correspondence should be addressed to Ye Qinghua(email: yeqh@itpcas.ac.cn) | 2004 | Science China Earth Sciences2004，47，11： | 22 |
| 3 | Monitoring lake changes of Qinghai-Tibetan Plateau over the past 30 years using satellite remote sensing data显示文摘During the years 2006–2009,lakes in the Qinghai-Tibetan Plateau(QTP)were investigated using satellite remote sensing strategies.We report the results of this investigation as well as follow-up research and expanded work.For the investigation,we mainly focused on lakes whose areas are more than 1 km2.The remote sensing data that we used included 408 scenes of CBERS CCD images and 5 scenes of Landsat ETM?images in Qinghai Province and Tibet Autonomous Region.All these data were acquired around years 2005–2006.Besides remote sensing images,we also collected 1,259 topographic maps.Numbers and areas of lakes were analyzed statistically,which were then compared with those coming from the first lake investigation(implemented between the1960s and 1980s).According to our investigation,up to and around year 2005–2006,the total number of lakes in the QTP was 1,055(222 in Qinghai and 833 in Tibet),accounting for more than 30%of that of China.Thirty newborn lakes with area[1 km2were found,and 5 dead lakes with initial area[1 km2were also found.Among those 13 big lakes([500 km2),Yamzhog Yumco had seriously shrunk,and it has continued to shrink in recent years;Qinghai Lake had shrunk during the period,but some new researches indicated that it has been expanding since the year 2004;Siling Co,Nam Co,and Chibuzhang Co had expanded in the period.We divided the newborn lakes into six categories according to their forming reasons,including river expansion,wetland conversion,etc.The changes of natural conditions led to the death of four lakes,and human exploitation was the main reason for the death of Dalianhai Lake in Qinghai.We picked out three regions which were sensitive to the change of climate and ecological environment:Nagqu Region,Kekexili Region,and the source area of the Yellow River(SAYR).Lakes in both Nagqu and Kekexili have been expanded;meanwhile,most lakes in the SAYR have obviously been shrunk.These regional patterns of lake changes were highly related to variations of temperature,glacier,precipitation,and evaporation.Our investigation and analysis will provide references for researches related to lake changes in the QTP and the response to climate fluctuations. | Wei Wan Pengfeng Xiao Xuezhi Feng Hui Li Ronghua Ma Hongtao Duan Limin Zhao | 2014 | Chinese Science Bulletin2014，59，10： | 22 |
| 4 | Emerging ultra-narrow-band cyan-emitting phosphor for white LEDs with enhanced color rendition显示文摘Phosphor-converted white LEDs rely on combining a blue-emitting InGaN chip with yellow and red-emitting luminescent materials.The discovery of cyan-emitting(470-500 nm)phosphors is a challenge to compensate for the spectral gap and produce full-spectrum white light.Na_(0.5)K_(0.5)Li_(3)SiO_(4):Eu^(2+)(NKLSO:Eu^(2+))phosphor was developed with impressive properties,providing cyan emission at 486 nm with a narrow full width at half maximum(FWHM)of only 20.7 nm,and good thermal stability with an integrated emission loss of only 7% at 150℃.The ultra-narrow-band cyan emission results from the high-symmetry cation sites,leading to almost ideal cubic coordination for UCr_(4)C_(4)-type compounds.NKLSO:Eu^(2+) phosphor allows the valley between the blue and yellow emission peaks in the white LED device to be filled,and the color-rendering index can be enhanced from 86 to 95.2,suggesting great applications in full-spectrum white LEDs. | Ming Zhao Hongxu Liao Maxim S.Molokeev Yayun Zhou Qinyuan Zhang Quanlin Liu Zhiguo Xia | 2019 | Light(Science & Applications)2019，8，1： | 21 |
| 5 | Variation of precipitation for the last 300 years over the middle and lower reaches of the Yellow River显示文摘The precipitation at 17 stations over the middle and lower reaches of the Yellow River is reconstructed during the period of 1736―1910, using the snow and rainfall records in the Qing Dynasty, together with the instrumental observation data of precipitation and farmland soil moisture content. The soil physics model related to rainfall infiltration and the surface water bal-ance equation are taken as main reconstruction methodology. The field infiltration experiment by artificial rainfall is conducted to check the reliability. And the precipitation series over the middle and lower reaches of the Yellow River and its 4 sub-regions are established, going back to 1736. Analysis of the time series indicates that the abrupt change of precipitation from high to low oc-curs around 1915 over the middle and lower reaches of the Yellow River. During the three peri-ods of 1791―1805, 1816―1830 and 1886―1895, the precipitation is markedly higher than the mean of the series. While both the periods of 1916―1945 and 1981―2000 are characterized by less precipitation. Three periodicities of 22―25a, 3.9a and 2.7a are shown in the precipitation fluctuation over the middle and lower reaches of the Yellow River. Moreover, the periodical signal of 22―25a becomes weaker and weaker since the abrupt change of 1915 and disappears in the late 1940s, and then the periodical signal of 35―40a appears instead. | ZHENG Jingyun HAO Zhixin GE Quansheng | 2005 | Science China Earth Sciences2005，48，12： | 20 |
| 6 | Trend analysis of sediment grain size and sedimentary process in the central South Yellow Sea显示文摘With the method of trend analysis of sediment grain size, the sediment transport trend of the fine-grained sediments area in the central South Yellow Sea was studied. The results demonstrated that there is a sedimentation center around the point of 123.4° E, 35.1°N, and the sediments outside the center are transported to it. The patterns of sediment transportation and deposition in the Yellow Sea should be controlled by cyclonic circulation (including the Yellow Sea Cold Water Mass) and cold water gyre. The study also showed that the method of trend analysis of sediment grain size has prospective utilization in the fine-grained sediment deposited area on large-scale continental shelf. | SHI Xuefa CHEN Chunfeng LIU Yanguang REN Hong WANG Huiyan | 2002 | Chinese Science Bulletin2002，47，14： | 17 |
| 7 | Tidal current-induced formation——storm-induced change——tidal current-induced recovery——Interpretation of depositional dynamics of formation and evolution of radial sand ridges on the Yellow Sea seafloor显示文摘The results of simulated tidal current field, wave field and storm-induced current field are employed to interpret the depositional dynamic mechanism of formation and evolution of the radial sand ridges on the Yellow Sea seafloor. The anticlockwise rotary tidal wave to the south of Shandong Peninsula meets the following progressive tidal wave from the South Yellow Sea, forming a radial current field outside Jianggang. This current field provides a necessary dynamic condition for the formation and existence of the radial sand ridges on the Yellow Sea seafloor. The results of simulated 'old current field (holocene)' show that there existed a convergent-divergent tidal zone just outside the palaeo-Yangtze River estuary where a palaeo-underwater accumulation was developed. The calculated results from wave models indicate that the wave impact on the topography, under the condition of high water level and strong winds, is significant. The storm current induced by typhoons landing in the Yangtze River | 张长宽 张东生 张君伦 王震 | 1999 | Science China Earth Sciences1999，42，1： | 17 |
| 8 | Ulva prolifera green-tide outbreaks and their environmental impact in the Yellow Sea, China显示文摘The Ulva prolifera green tides in the Yellow Sea, China, which have been occurring since 2007, are a serious environmental problem attracting worldwide attention. Despite extensive research, the outbreak mechanisms have not been fully understood. Comprehensive analysis of anthropogenic and natural biotic and abiotic factors reveals that human activities, regional physicochemical conditions and algal physiological characteristics as well as ocean warming and biological interactions(with microorganism or other macroalgae) are closely related to the occurrence of green tides. Dynamics of these factors and their interactions could explain why green tides suddenly occurred in 2007 and decreased abruptly in 2017.Moreover, the consequence of green tides is serious. The decay of macroalgal biomass could result in hypoxia and acidification, possibly induce red tide and even have a long-lasting impact on coastal carbon cycles and the ecosystem. Accordingly, corresponding countermeasures have been proposed in our study for future reference in ecosystem management strategies and sustainable development policy. | Yongyu Zhang Peimin He Hongmei Li Gang Li Jihua Liu Fanglue Jiao Jianheng Zhang Yuanzi Huo Xiaoyong Shi Rongguo Su Naihao Ye Dongyan Liu Rencheng Yu Zongling Wang Mingjiang Zhou Nianzhi Jiao | 2019 | National Science Review2019，6，4： | 17 |
| 9 | 黄河2009年调水调沙期间河口水动力及悬沙输移变化特征显示文摘根据2009年7月黄河第九次调水调沙期间和结束后在黄河口两个站位观测的水文泥沙资料,对调水调沙期间和结束后河口的水动力和悬沙分布特征进行了对比分析,并对潮周期内悬沙输移过程进行了探讨。结果表明:调水调沙期间相比于结束后,落潮动力加强,涨潮动力有所减弱,尤其在水体表层表现明显,河口切变锋类型不同,其出现时间长度亦不同;调水调沙期间含沙量较大,垂向分布较复杂,而结束后含沙量低,垂向梯度变化较小;此外,调水调沙期间河口悬沙在输移过程中以沉降作用为主,并在涨急和落急时刻伴随着底沙的再悬浮,而结束后悬沙浓度降低幅度较大,泥沙再悬浮作用较强。 | 刘锋 陈沈良 周永东 彭俊 陈一强 任韧希子 | 2010 | 泥沙研究2010，35，6： | 16 |
| 10 | Chinese Yellow Wine Inhibit Production of Homocysteine-induced Extracellular Matrix Metalloproteinase-2 in Cultured Rat Vascular Smooth Muscle Cells显示文摘Objectives Regular consumption of moderate amounts of Chinese yellow wine is associated with a reduced risk of coronary disease. Matrix metalloproteinases (MMPs) that participate in extracellular matrix degradation have been involved in atherosclerotic plaque growth and instability. The present research aimed to study the effects of Chinese yellow wine on the production of homocysteine-induced extracellular MMP-2 in cultured rats' vascular smooth muscle cells. Methods The effects of different homocysteine levels (0-1000 ?滋mol/l) on MMP-2 production, and the effects of Chinese yellow wine with low alcohol concentrations (12-19%) on homocysteine-induced MMP-2 in cultured rat vascular smooth muscle cells (VSMCs) were examined using gelatin zymography and western blotting. The changes of MMP-2 under various treatments for 12 h, 24 h and 48 h were further compared. Results Homocysteine (50-1000 ?滋mol/l) increased the production of MMP-2 significantly in a dose-dependent manner. Increased production of MMP-2 induced by homocysteine was reduced by extracellularly added Chinese yellow wine. Production of MMP-2 under various treatments for 48 h increased more than 12 h and 24 h. Conclusions Extracellularly added Chinese yellow wine decreased homocysteine-induced MMP-2 secretion. The inhibitory effect of yellow wine on the activation of MMP-2 might contribute to their beneficial effects on the cardiovascular system. | 郭航远 邢杨波 彭放 杨彪 裘宇芳 游斌权 李刚 朱敏 袁敏 何益平 周妍 Lee Jong-Dae | 2007 | South China Journal of Cardiology2007，0，1： | 16 |
| 11 | 花语浅涉显示文摘劳动孕育和创造了语言,文明则扩展和丰富了语言。随着社会文明的提高,语言的表达方式也由有声表达法逐步繁衍了许多无声表达法:书刊、贺卡、舞蹈、绘画、计算机语言等等。眼下,我们还常常会看到:新婚燕尔,送上一簇鲜花,衷心祝福;一曲终了,献上一个花篮,热烈祝贺;有人病了,送去一束鲜花,祝愿康复;先人作古,一只花圈寄托无限哀思。花,在我们现代生活中崭露头角,它艳而不俗,含而不露最能表达出无法言传的情感。当今,借花寓意已被整个文明社会所接受和推崇,形成了一种特殊的社会现象。我以为。 | 顾雪梁 | 1994 | 现代外语1994，17，3： | 15 |
| 12 | 近60年来汾河入黄河水沙演变特征及驱动因素显示文摘基于汾河河津站1950~2005年的实测径流和输沙数据,采用Mann-Kendall检验等多种统计方法分析了汾河入黄河的水沙演变特征及驱动因素。结果表明:入黄河水沙量年际波动较大,呈明显减少趋势,且输沙减少的趋势性要强于径流;径流与输沙发生重要突变的时间都是1980年,说明径流量的减少在一定程度上直接影响着输沙量的变化。降水量的减少是径流减少的重要原因,但二者的变化并不是完全一致的,20世纪60年代以来尤其是1980年以后,降水对径流的影响有所减弱,在其他自然条件(如蒸发)相对不变的情况下,人类活动是径流减少的主要驱动因素。根据理论分析,受人类活动的影响,1961~1980年的累积减沙量为108610×104t,平均每年减少5430.50×104t,1981~2005年的累积减沙量为93324×104t,平均每年减少3732.96×104t。 | 刘宇峰 孙虎 原志华 | 2010 | 山地学报2010，28，6： | 15 |
| 13 | The wind-water two-phase erosion and sediment-producing processes in the middle Yellow River basin, China显示文摘Based on data from the middle Yellow River basin, a wind-water two-phase mechanism for erosion and sediment-producing processes has been found. By using this mechanism, the extremely strong erosion and sediment yield in the study area can be better explained. The operation of wind and water forces is different in different seasons within a year. During winter and spring, strong wind blows large quantities of eolian sand to gullies and river channels, which are temporally stored there. During the next summer, rainstorms cause runoff that contains much fine loessic material and acts as a powerful force to carry the previously prepared coarse material. As a result, hyperconcentrated flows occur, resulting in high-intensity erosion and sediment yield. | 许炯心 | 2000 | Science China Earth Sciences2000，43，2： | 14 |
| 14 | Quantitatively distinguishing sediments from the Yangtze River and the Yellow River using δEu_N-ΣREEs plot显示文摘Sediment samples were collected from the lower channel of the Yangtze River and the Yellow River and the contents of rare earth elements (REEs) were measured. In addition, some historical REEs data were collected from published literatures. Based on the δEuN-ΣREEs plot, a clear boundary was found be-tween the sediments from the two rivers. The boundary can be described as an orthogonal polynomial equation by ordinary linear regression with sediments from the Yangtze River located above the curve and sediments from the Yellow River located below the curve. To validate this method, the REEs con-tents of sediments collected from the estuaries of the Yangtze River and the Yellow River were meas-ured. In addition, the REEs data of sediment Core 255 from the Yangtze River and Core YA01 from the Yellow River were collected. Results show that the samples from the Yangtze River estuary and Core 255 almost are above the curve and most samples from the Yellow River estuary and Core YA01 are below the curve in the δEuN-ΣREEs plot. The plot and the regression equation can be used to distin-guish sediments from the Yangtze River and the Yellow River intuitively and quantitatively, and to trace the sediment provenance of the eastern seas of China. The difference between the sediments from two rivers in the δEuN-ΣREEs plot is caused by different mineral compositions and regional climate patterns of the source areas. The relationship between δEuN and ΣREEs is changed little during the transport from the source area to the river, and from river to the sea. Thus the original information on mineral compositions and climate of the source area was preserved. | JIANG FuQing ZHOU XiaoJing LI AnChun LI TieGang | 2009 | Science China Earth Sciences2009，52，2： | 14 |
| 15 | A MATHEMATICAL MODEL FOR UNSTEADY SEDIMENT TRANSPORT IN THE LOWER YELLOW RIVER显示文摘A one-dimensional mathematical model for unsteady sediment transport in the Lower Yellow River is developed. A coefficient of sediment distribution is defined to represent the ratio of the bottom to the average concentration under the equilibrium conditions. The coefficient is not constant and is evaluated by using an empirical expression obtained by integrating the sediment concentration along water depth. The concentration distributions and the mean diameter distributions of suspended sediment in the transversal direction are also estimated in this model. A four-point (Preismann type) finite difference scheme and TDMA are employed in the numerical method. Three typical floods occurd in 1977,1982 and 1996, respectively, in the Lower Yellow River from Tiexie to Shunkou with a length of 393.67km are numerically simulated with the model. The computed results, such as the water stage, discharge, and sediment concentration agree well with the measured data. | ZHANG Hongwu1, HUANG Yuandong1 and ZHAO Lianjun2 1 Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China 2 Yellow River Institute of Hydraulic Research, Zhengzhou 450003, China | 2001 | International Journal of Sediment Research2001，16，2： | 13 |
| 16 | DEVELOPMENT OF COMMON WHEAT GERM-PLASM RESISTANT TO BARLEY YELLOW DWARF VIRUS BY BIOTECHNOLOGY显示文摘Barley yellow dwarf virus (BYDV) is one of the most serious wheat diseases in China. So far no resistance has been described in common wheat. A certain level of BYDV resistance was found in thirteen Triticeae species. Thinopyrum intermedium, two octoploids derived from TH. intermedium/wheat, Zhong 4 awnless and TAF46, and one disomic addition line, L1 derived from TAF46, showed good resistance to BYDV by enzyme linked immunosorbent assay (ELISA). Two wheat/TA. intermedium translocation lines, CPI 119880 and CPI 119899, showing good BYDV resistance were developed from L1 by using both CSph mutant and tissue culture. It is found that their BYDV resistance was controlled by a single dominant gene. Two cDNA probes pEleAcc3 and pPJN8 (E1-T1) were screened for detecting Th. intermedium DNA in wheat background. A specific band for the DNA of Th. intermedium and its derivatives was found in Southern hybridization. It is also possible to determine the size of the alien segment by comparing the relative density | 辛志勇 徐惠君 陈孝 林志珊 周广和 钱幼亭 成卓敏 P. J. LARKIN P. BANKS R. APPELS B. GLARKE AND R. I. S. BRETTELL | 1991 | Science China Chemistry1991，34，9： | 13 |
| 17 | Protective Effect of Hydroxysafflor Yellow A on Inflammatory Injury in Chronic Obstructive Pulmonary Disease Rats显示文摘Objective: To investigate the attenuating effect of Hydroxysafflor yellow A(HSYA) on inflammatory injury in chronic obstructive pulmonary disease(COPD). Methods: Rats were randomly assigned to 7 groups according to body weight including normal control group, HSYA blank group(76.8 mg/kg), COPD group, COPD+HSYA(30, 48, 76.8 mg/kg) groups and COPD+dexamethasone(2 mg/kg), 10 in each group. Passive cigarette smoke and intratracheal instil ation of lipopolysaccharides were used to establish a COPD model in rats. Hematoxylin and eosin staining of lung tissue sections was used, real-time polymerase chain reaction(PCR) was used to assay m RNA levels of some cytokines in lung tissues, the cytokines in bronchoalveolar lavage fluid(BALF) were measured by enzyme-linked immunosorbent assay(ELISA), Western blot analysis was used to determine phosphorylated p38 mitogen-activated protein kinase(MAPK) levels in lung tissues, and nuclear factor-κB(NF-κB) p65 protein levels in lung tissues were detected by immunohistochemistry. Results: Lung alveolar septa destruction, alveolus fusion, inflammatory cel infiltration, and bronchiole exudation were observed. These pathological changes were al eviated in the COPD+HSYA group. The m RNA expression of inflammatory factors were significantly increased in lung tissues from COPD rats(all P<0.01) and were inhibited by HSYA. Levels of inflammatory cytokines in BALF of COPD rats were significantly increased(all P<0.01) which were inhibited by HSYA(all P<0.01, 48, 76.8 mg/kg). The levels of p38 MAPK phosphorylation and p65 in lung tissues of COPD rats were significantly increased(al P<0.01) and were suppressed by HSYA(all P<0.01, 48, 76.8 mg/kg). Conclusions: HSYA could alleviate inflammatory cell infiltration and other pathological changes in the lungs of COPD rats. HSYA could inhibit inflammatory cytokine expression, and increase phosphorylation of p38 MAPK and NF-κB p65 in the lungs of COPD rats. The protective mechanism of HSYA to inhibit COPD inflammation might be by attenuating NF-κB and p38 MAPK signal transduction. | JIN Ming XUE Chang-jiang WANG Yu DONG Fang PENG Yuan-yuan ZHANG Ya-dan ZANG Bao-xia TAN Li | 2019 | Chinese Journal of Integrative Medicine2019，25，10： | 12 |
| 18 | Streamflow response to climate variability and human activities in the upper catchment of the Yellow River Basin显示文摘Both sensitivity-based method and simulation method are used to analyze the streamflow response to climate variability and human activities in the upper catchment of the Yellow River Basin (UYRB) in this study. The separation regime of effects from climate variability and human activities is investigated. Results show that the changes of streamflow are more sensitive to precipitation than potential evapotranspiration (PET). Effect of climate variability on streamflow estimated using the sensitivity-based method is weak in the upper catchment of Jimai station, and strong in the upper catchment of Lanzhou station, where the climate effects accounted for about 50% of total streamflow changes. Effects of human activities on streamflow accounted for about 40% in the UYRB, with weaker effects in the upper catchment of Tangnaihai station than those in the upper catchment of Lanzhou station. Both climate variability and human activities are main factors to affect the changes of streamflow in the UYRB. | ZHAO FangFang XU ZongXue ZHANG Lu ZUO DePeng | 2009 | Science China(Technological Sciences)2009，52，11： | 12 |
| 19 | Dynamic Changes in the Wetland Landscape Pattern of the Yellow River Delta from 1976 to 2016 Based on Satellite Data显示文摘The Yellow River Delta wetland is the youngest wetland ecosystem in China's warm temperate zone. To better understand how its landscape pattern has changed over time and the underlying factors responsible, this study analyzed the dynamic changes of wetlands using five Landsat series of images, namely MSS(Mulri Spectral Scanner), TM(Thematic Mapper), and OLI(Operational Land Imager) sensors in 1976, 1986, 1996, 2006, and 2016. Object-oriented classification and the combination of spatial and spectral features and both the Normalized Difference Vegetation Index(NDVI) and Normalized Difference Water Index(NDWI), as well as brightness characteristic indices, were used to classify the images in eCognition software. Landscape pattern changes in the Yellow River Delta over the past 40 years were then delineated using transition matrix and landscape index methods. Results show that: 1) from1976 to 2016, the total area of wetlands in the study area decreased from 2594.76 to 2491.79 km^2, while that of natural wetlands decreased by 954.03 km^2 whereas human-made wetlands increased by 851.06 km^2. 2) The transformation of natural wetlands was extensive: 31.34% of those covered by Suaeda heteropteras were transformed into reservoirs and ponds, and 24.71% with Phragmites australis coverage were transformed into dry farmland. Some human-made wetlands were transformed into non-wetlands types: 1.55% of reservoirs and ponds became construction land, and likewise 21.27% were transformed into dry farmland. 3) From 1976 to 2016, as the intensity of human activities increased, the number of landscape types in the study area continuously increased. Patches were scattered and more fragmented. The whole landscape became more complex. In short, over the past 40 years, the wetlands of the Yellow River Delta have been degraded, with the area of natural wetlands substantially reduced. Human activities were the dominant forces driving these changes in the Yellow River Delta. | CONG Pifu CHEN Kexin QU Limei HAN Jianbo | 2019 | Chinese Geographical Science2019，29，3： | 12 |
| 20 | Distributed modeling of monthly air temperatures over the rugged terrain of the Yellow River Basin显示文摘Our analyses of the monthly mean air temperature of meteorological stations show that altitude,global solar radiation and surface effective radiation have a significant impact on air temperature.We set up a physically-based empirical model for monthly air temperature simulation.Combined the proposed model with the distributed modeling results of global solar radiation and routine meteorological observation data,we also developed a method for the distributed simulation of monthly air temperatures over rugged terrain.Spatial distribution maps are generated at a resolution of 1 km×1 km for the monthly mean,the monthly mean maximum and the monthly mean minimum air temperatures for the Yellow River Basin.Analysis shows that the simulation results reflect to a considerable extent the macro and local distribution characteristics of air temperature.Cross-validation shows that the proposed model displays good stability with mean absolute bias errors of 0.19℃-0.35℃.Tests carried out on local meteorological station data and case year data show that the model has good spatial and temporal simulation capacity.The proposed model solely uses routine meteorological data and can be applied easily to other regions. | ZENG Yan QIU XinFa HE YongJian SHI GuoPing LIU ChangMing | 2009 | Science China Earth Sciences2009，52，5： | 11 |
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