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Organic Phosphorus in Shallow Lake Sediments in Middle and Lower Reaches of the Yangtze River Area in China 被引量:24
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作者 JIN Xiang-Can WANG Sheng-Rui +1 位作者 CHU Jian-Zhou WU Feng-Chang 《Pedosphere》 SCIE CAS CSCD 2008年第3期394-400,共7页
Thirteen sediment core samples(0-10 cm) were taken from the seven lakes in the middle and lower reaches of the Yangtze River to determine the contents and distributions of organic phosphorus(P) fractions in the sedime... Thirteen sediment core samples(0-10 cm) were taken from the seven lakes in the middle and lower reaches of the Yangtze River to determine the contents and distributions of organic phosphorus(P) fractions in the sediments of the shallow lakes in the area.The organic P fractions in the sediments were in the order of moderately labile organic P(MLOP) > moderately resistant organic P(MROP) > highly resistant organic P(HROP) > labile organic P(LOP),with average proportional ratios of 13.2:2.8:1.3:1.0.LOP,MLOP,and MROP were significantly related to the contents of total organic carbon(TOC),water-soluble P(WSP),algal-available P(AAP),NaHCO3-extractable P(Olsen-P),total P(TP),organic P(OP),and inorganic P(IP).However,HROP was significantly related to OP and weakly correlated with TOC,WSP,AAP,Olsen-P,TP or IP.This suggested that organic P,especially LOP and MLOP in sediments,deserved even greater attention than IP in regards to lake eutrophication.In terms of organic P,sediments were more hazardous than soils in lake eutrophication.Although OP concentrations were higher in moderately polluted sediment than those in heavily polluted sediment,LOP and MLOP were higher in the heavily polluted sediment,which indicated that heavily polluted sediment was more hazardous than moderately polluted sediment in lake eutrophication. 展开更多
关键词 BIOAVAILABILITY chemical extracted phosphorus lake sediment middle and lower reaches of the Yangtze river area organic phosphorus fractions
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A Preliminary Study on the Rational Utilization of Land Resources in the Poverty-Stricken Mountainous Areas in the Upper Reaches of the Yangtze River:A Case Study of Xueshan Township 被引量:2
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作者 Jia WANG Leijin LONG 《Asian Agricultural Research》 2020年第2期17-24,27,共9页
As one of the most fragile alpine plateau and canyon areas in China,the upper reaches of the Yangtze River are the key areas of ecological construction in China.It is also a key area for poverty alleviation in the cou... As one of the most fragile alpine plateau and canyon areas in China,the upper reaches of the Yangtze River are the key areas of ecological construction in China.It is also a key area for poverty alleviation in the country.Therefore,it is necessary to take into account the dual goals of poverty reduction and ecological environment construction,and explore a win-win road of ecological construction and poverty alleviation in line with the reality of the upper reaches of the Yangtze River.Taking Xueshan Township,Luquan Yi and Miao Autonomous County,Yunnan Province,which is located in the poor mountainous area of the upper reaches of the Yangtze River as an example,based on many field investigations and existing investigation and statistical data,this paper analyzes the current situation and main problems of land use in Xueshan Township,and then puts forward measures and suggestions for rational utilization of land resources in Xueshan Township.This can provide a necessary reference for the next implementation of rural revitalization strategy and ecological construction. 展开更多
关键词 Land resources RATIONAL utilization upper reaches of the YANGTZE river POOR mountainous areas Xueshan Township Luquan COUNTY
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The Background of Regional Lead Isotopic Compositions and Its Application in the Lower and Middle Reaches of the Yangtze River and Neighbouring Areas 被引量:1
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作者 Ma Zhendong and Shan Guangxiang Geochemistry Institute, China University of Geosciences, Wuhan, Hubei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第2期158-170,共13页
The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of diff... The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of different geological formations and units are con-trolled by the primary mantle heterogeneity, dynamic process of crust-mantle interchange,abundances of uraninm, thorium and lead of various layers of the earth and timing. Studies onthe background of regional isotopic compositions may offer significant information forgeochemical regionalization, tracing of sources of ore-forming materials, and regionalprognosis of ore deposits. 展开更多
关键词 background of regional lead isotopic compositions tracing action lower and middle reaches of the Yangtze river and neighbouring areas
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Floristic Study of Vascular Plants in Typical Plant Communities in the Middle and Upper Reaches of the Yarlung Zangbo River
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作者 GE Qingsong QU Xingle +2 位作者 LUO Daqing ZHENG Weilie FANG Jiangping 《Journal of Landscape Research》 2019年第5期123-129,134,共8页
[Objective] Species composition and flora of vascular plants in the middle and upper reaches of the Yarlung Zangbo River were analyzed,to provide scientific basis for the estimation and protection of plant diversity,c... [Objective] Species composition and flora of vascular plants in the middle and upper reaches of the Yarlung Zangbo River were analyzed,to provide scientific basis for the estimation and protection of plant diversity,construction of ecological security shelter for the Tibetan Plateau.[Methods] In the middle and upper reaches of the Yarlung Zangbo River,quadrat (line transect) method was applied to investigate the phytocoenoses in sample plots,and relative literature was used to analyze the floristic composition and floristic element of vascular plants in the middle and upper reaches of the Yarlung Zangbo River.[Results]① There are 96 species (including subspecies and variations),69 genera of 35 vascular plant families,accounting for 16.83%,5.48%,1.66% and 11.63%,2.02%,0.31% of total vascular plant families,genera and species in Tibet and China.② There are 24 monotypic-genus families,accounting for 68.57% of the total family number in the local area;22 monotypic-species families,accounting for 62.86% of the total family number in the local area.Local flora shows the characteristics of ancient relict,such as Euphorbiaceae,Rubiaceae,Liliaceae and Ranunculaceae,they are all ancient primitive groups of the third flora and the fourth flora.③ Local vascular plant genera fall into 10 areal types and 8 variations.④ Temperate elements are much more than tropical elements,R/T is 0.19,indicating that vascular plants have typical temperate nature and residual tropical nature.There are only a few endemic genera,but more endemic species to the local area,and these species are closely related,of which there are some transitional species,indicating that local flora is too young to experience more differentiation and specialization.⑤ There are 24 Chinese endemic species,accounting for 25% of total number of species in the local area;among which there are 12 endemic species to Tibet,accounting for 50% of endemic species to China,12.5% of total number of species in the local area.Four key wild plant species are included in the second batch of national key protection.[Conclusions]① There are scarce plant groups in the local area.② Among the obvious advantages,single-genus (species) families possess the absolute advantage,and the flora has ancient origins.③ The local flora has diversified distribution types,and the complicated geographical elements.④ Temperate species possess obvious advantages,and the flora is young.⑤ Rich unique and rare species have high species diversity protection and research value. 展开更多
关键词 The middle and upper reaches of the Yarlung Zangbo river TYPICAL plant community Vascular plants FLORA
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Analysis on Landscape Pattern in the Upper and Middle Reaches of Yarlung Zangbo River:Taking Zhongba County,Angren County, Rikaze City as Example
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作者 XIONG Donghong YANG Zhong +1 位作者 CHEN Xuehua ZHOU Hongyi 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期951-957,共7页
Taking Zhongba County, Angren County, Rikaze City located at the Upper and Middle Reaches of Yarlung Zangbo River as landscape units , this paper studied the difference of the landscape pattern under various degrees o... Taking Zhongba County, Angren County, Rikaze City located at the Upper and Middle Reaches of Yarlung Zangbo River as landscape units , this paper studied the difference of the landscape pattern under various degrees of human disturbance in the three areas. The results showed that: the three areas all reflected the same characteristic of landscape pattern in Qinghai-Tibet Plateau, the natural landscapes were in the absolute dominant position. However, from Zhangba to Rikaze, with human disturbance intensity increasing, anthropogenic features of landscapes became more and more outstanding, In Zhongba, the landscape structure appeared to be simpler with coarse grains and a less rich diversity, Conversely, in Rikaze, the landscape showed a complicated shape with finer grains and a relatively richer diversity, This reflected that the impact of human activities to natural landscape behaved a gradually-growing trend from the upper reach to the middle one of Yarlung Zangbo River Basin. 展开更多
关键词 characteristics of landscape pattern impact of human activity the upper and middle reaches of Yarlung Zangbo river
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Unsteadiness of COD in the Upper and Middle Reaches of Minjiang River
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作者 Liu Zuhan Zhang Bin +2 位作者 Wang Lili Qin Fachao Liu Lijun 《Chinese Journal of Population,Resources and Environment》 2010年第4期65-68,共4页
This paper explores and identifies the rules of the unsteady evolution of COD in the upper and middle reaches of Minjiang River through multi-scale analysis on the weekly COD data for the last six years provided by th... This paper explores and identifies the rules of the unsteady evolution of COD in the upper and middle reaches of Minjiang River through multi-scale analysis on the weekly COD data for the last six years provided by the Water Quality Monitoring Station,Minjiang River Bridge,Leshan City,Sichuan Province.The results of the wavelet analysis indicate that the COD index oscillates alternatively and differently at each time-scale in an oneyear cycle,and the density of COD,subjected to the runoff volume,the effects of Wenchuan Earthquake and agricultural seeding and industrial construction,etc.,is high in winter and spring,mild in summer and autumn. 展开更多
关键词 wavelet analysis COD the upper and middle reaches of the Minjiang river
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The SIA method for spatial analysis of precipitation in the upper-middle reaches of the Yangtze River 被引量:14
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作者 ZHOUSuoquan XUEGenyuan +6 位作者 GONGPeng CHENJingming ZHANGHongping ZHOUZhijiang FANXiong DENGXiaochun WUZhanping 《Journal of Geographical Sciences》 SCIE CSCD 2005年第2期223-238,共16页
Using geographic information system (GIS) techniques and the newest seasonal and annual average precipitation data of 679 meteorological stations from 1971 to 2000, the multiple regressions equations of the precipitat... Using geographic information system (GIS) techniques and the newest seasonal and annual average precipitation data of 679 meteorological stations from 1971 to 2000, the multiple regressions equations of the precipitation and topographical variables are established to extract the effect of topography on the annual and seasonal precipitation in the upper-middle reaches of the Yangtze River. Then, this paper uses a successive interpolation approach (SIA), which combines GIS techniques with the multiple regressions, to improve the accuracy of the spatial interpolation of annual and seasonal rainfall. The results are very satisfactory in the case of seasonal rainfall, with the relative error of 6.86%, the absolute error of 13.07 mm, the average coefficient of variation of 0.070, and the correlation coefficient of 0.9675; in the case of annual precipitation, with the relative error of 7.34%, the absolute error of 72.1 mm, the average coefficient of variation of 0.092, and the correlation coefficient of 0.9605. The analyses of annual mean precipitation show that the SIA calculation of 3-5 steps considerably improves the interpolation accuracy, decreasing the absolute error from 211.0 mm to 62.4 mm, the relative error from 20.74% to 5.97%, the coefficient of variation from 0.2312 to 0.0761, and increasing the correlation coefficient from 0.5467 to 0.9619. The SIA iterative results after 50 steps identically converge to the observed precipitation. 展开更多
关键词 the upper-middle reaches of the Yangtze river precipitation resource spatial analysis successive interpolation approach (SIA)
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Impact of vegetation restoration on hydrological processes in the middle reaches of the Yellow River,China 被引量:4
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作者 XIN Zhong-bao YU Xin-xiao 《Forestry Studies in China》 CAS 2009年第4期209-218,共10页
Sediment discharge from the Yellow River originates mainly from the drainage area between Hekouzhen and Longmen, i.e., the Helong area. Spatial-temporal variations of the vegetation cover in this area during the 1981-... Sediment discharge from the Yellow River originates mainly from the drainage area between Hekouzhen and Longmen, i.e., the Helong area. Spatial-temporal variations of the vegetation cover in this area during the 1981-2007 period have been investigated using GIMMS and SPOT VGT NDVI data. We have also analyzed the interannual variations in vegetation cover and changes in annual runoff and sediment discharge, the consequences from precipitation change and the Grain for Green Project (GGP). The results show that vegetation cover of the Helong area has increased during the 1981-2007 period. The northwestern part the Helong area, where the flat sandy lands are covered by grass, has experienced the largest increase. The region where the vegetation cover has declined is largely found in the southern and southeastern Helong area, which is a gullied hilly area or forested. Although precipitation was relatively low during the 1999-2007 period, the vegetation cover showed a significant increase in the Helong area, due to the implementation of the GGP. During this period, the most significant improvement in the vegetation cover occurred mainly in the gullied hilly areas of the Loess Plateau, such as the drainage basins of the Kuyehe and Tuweihe rivers and the middle and lower reaches of the Wudinghe and Yanhe rivers. A comparison of the average annual maximum NDVI between the earlier (1998-2002) stage and the next five years (2003-2007) of the GGP indicates that the areas with increases of 10% and 20% in NDVI account for 72.5% and 36.4% of the total area, respectively. Interannual variation of annual runoff and sediment discharge shows a declining trend, especially since the 1980s, when the decrease became very obvious. Compared with the 1950-1969 period, the average runoff during the 1980-2007 period was reduced by 34.8 × 10^8 m3 and the sediment discharge by 6.4 ×10^8 t, accounting for 49.4% and 64.9% of that in the 1950-1969 period, respectively. There is a positive correlation between the annual maximum NDVI and annual runoff and sediment discharge. This correlation was reversed since the implementation of the GGP in 1999 and vegetation cover in the He- long area has increased, associated with the decrease in runoff and sediment discharge. Less precipitation has been an important fac- tor driving the decrease in runoff and sediment discharge during 1999 2007. However, restoration and improvement of the vegetation cover may also have played a significant role in accelerating the decrease in annual runoff and sediment discharge by enhancing evapotranspiration and alleviating soil erosion. 展开更多
关键词 middle reaches of the Yellow river Hekouzhen to Longmen area (Helong area vegetation restoration Grain forGreen Project (GGP) runoff and sediment
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Two series of copper-gold deposits in the middle and lower reaches of the Yangtze River area (MLYRA) and the hydrogen, oxygen, sulfur and lead isotopes of their ore-forming hydrothermal systems 被引量:40
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作者 周涛发 袁峰 +1 位作者 岳书仓 赵勇 《Science China Earth Sciences》 SCIE EI CAS 2000年第S1期208-218,共11页
Based on studies on the geological characteristics of the copper-gold deposits in the middle and lower reaches of the Yangtze River area (MLYRA) and their hydrogen, oxygen, sulfur and lead isotope compositions, it is ... Based on studies on the geological characteristics of the copper-gold deposits in the middle and lower reaches of the Yangtze River area (MLYRA) and their hydrogen, oxygen, sulfur and lead isotope compositions, it is concluded that there existed two series of copper-gold deposits. They are evolutional products of two ore-forming hydrothermal systems in different geodynamic settings and geological era. Series I is stratiform or stratabound copper-gold deposits. These deposits were formed by submarine exhalation and sedimentation of hydrothermal solutions in Her-cynian tensional tectonic environment after bot brine ascending along contemporaneous faults and exhaled into the sea-floor. Series II consists of copper-gold deposits related to medium and acidic magmatic intrusions. Their mineralizations took place in Yanshanian in a tensional or a transitional period to the tensional tectonic environment from the composite of the tethys tectonic regime and the Paleo-Pacific ocean tectonic regime, as well as in the upper mantle doming and crustal thinning environment. Copper-gold deposits were formed from the hydrothermal fluids, mixtures of magmatic water and part of meteoric water, by complex water-rock interactions and coupling dynamic processes of transport-chemical reactions. Superposition is an important condition for the formation of the large-scale copper-gold ore deposits. 展开更多
关键词 fluid ORE-FORMING system ISOTOPE copper-gold deposits the middle and lower reaches of the YANGTZE river area.
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Quantitative Classification and Ordination of Plant Communities in the Upper and Middle Reaches of the Yarlung Zangbo River Basin 被引量:11
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作者 WANG Tong WANG Jingsheng +3 位作者 DING Yuke LIU Wenjing BAO Xiaoting LI Chao 《Journal of Resources and Ecology》 CSCD 2019年第4期389-396,共8页
Based on vegetation survey data and environmental data of the Yarlung Zangbo River Basin, we conducted a quantitative ecological analysis of the vegetation community composition and the relationship between species an... Based on vegetation survey data and environmental data of the Yarlung Zangbo River Basin, we conducted a quantitative ecological analysis of the vegetation community composition and the relationship between species and the environment in the study area. The results showed that 44 sampling sites and 68 plant species in the study area can be classified into seven subtypes: Artemisia minor + Stipa purpurea;Artemisia demissa + Stipa purpurea + Artemisia wellbyi;Kobresia pygmaea;Trikeraia hookeri;Sophora moorcroftiana + Cotoneaster multiflorus + Pennisetum centrasiaticum;Artemisia frigida;Potentilla fruticosa + Orinus thoroldii. Detrended correspondence analysis(DCA) indicated that both longitude and altitude play important roles in site and species distribution patterns. In addition, canonical correspondence analysis(CCA) revealed that in the upper and middle reaches of the Yarlung Zangbo River Basin, changes in temperature and precipitation caused by longitude are the main factors controlling the formation and transition of vegetation community types. Moreover, natural vegetation could be divided into three types: desert steppe community(source area), alpine steppe community(middle reaches region), and shrub community(confluence of Yarlung Zangbo River and Nyangqu River). 展开更多
关键词 upper and middle reaches of the Yarlung Zangbo river plant community quantitative classification ORDINATION
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Corridor effect of the spatial changes of landscape patterns in arid areas:A case study of the river corridor areas in the middle and lower reaches of Tarim River 被引量:2
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作者 ZHOU Huarong XIAO Duning ZHOU Kefa 《Chinese Science Bulletin》 SCIE EI CAS 2006年第A01期82-91,共10页
在 Tarim Riverare 的中间、更低的活动范围的河走廊区域在 Ruoqiang 从 Qara 水库 inYuli 县沿着河节由传统的绿走廊统治了到泰泰马·莱克县,它在 Tarim 河分水岭在社会、经济的发展起一个重要作用与一极其重要的生态的功能。对... 在 Tarim Riverare 的中间、更低的活动范围的河走廊区域在 Ruoqiang 从 Qara 水库 inYuli 县沿着河节由传统的绿走廊统治了到泰泰马·莱克县,它在 Tarim 河分水岭在社会、经济的发展起一个重要作用与一极其重要的生态的功能。对水路垂直的缓冲区地区从水路在 5-kminterval 开始沿着两个河边被定义(10 km 更宽) 用缓冲区地区分析的方法。每个缓冲区地区的风景模式索引被计算,并且主要风景模式的索引被分析以便在风景和补丁层次上揭示放射的效果和河走廊的特征。放射的宽度通常是在学习区域的 30 km 的结果表演,和罐头直到在潜水艇的 50-70 km -- 区域 FG1 因为学习区域位于二排水盆,与在他们之间的一个生态的空隙的地区。树林和沼泽地的 Thelandscapes 通常在 10 km 缓冲区地区以内被散布(它意味着缓冲区地区是离开水路的 5 km;一样此后) 沿着两个河边。而且,缓冲区地区越靠近到水路,补丁密度和最大的补丁索引是越多 higher。在为学习区域的生态、环境的新生,河走廊的生态的效果的程度必须充分被考虑,并且工程必须科学地并且讲道理地被计划并且设计。 展开更多
关键词 干旱带 水通道 通道效应 塔里木河
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ANALYSIS OF THE MICROPHYSICAL STRUCTURE OF RADIATION FOG IN XUANEN MOUNTAINOUS REGION OF HUBEI,CHINA 被引量:1
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作者 费冬冬 牛生杰 杨军 《Journal of Tropical Meteorology》 SCIE 2017年第2期177-190,共14页
Based on data of radiation fog events in Xuanen, Hubei province, 2010, this paper analyzes the microphysical process and evolution characteristics of radiation fogs with complicated substrate in the upper and middle r... Based on data of radiation fog events in Xuanen, Hubei province, 2010, this paper analyzes the microphysical process and evolution characteristics of radiation fogs with complicated substrate in the upper and middle reaches of the Yangtze River, and compares them with findings in other areas. Results are as follows: radiation fog in Xuanen is evidently weaker in droplet number concentration and liquid water content than land fogs in other areas. Its liquid water content fluctuates obviously, 0.01g/m3 with visibility of 1,000 meters, which is quite different from that in urban areas, but similar to the Nanling Mountains. Bi-modal droplet distribution is likely to occur in Xuanen mountain radiation fog(MRF) events. Statistical analysis shows that the observed droplet size distribution can be piecewise described well by the Gamma distribution. There is a positive correlation between liquid water content, fog droplet concentration and mean radius, especially in the development and dissipation stage. Condensation growth and droplet evaporation are major processes of Xuanen MRF. The dissipation time coincided with the time when the grass temperature reached the peak value, which indicated that dew evaporation is a key role in maintaining Xuanen MRF. In the early stage of dense fog's growth, droplets with diameter of over 20 micrometers can be observed with visibility of800-1,000 m, which might be caused by the transportation of low cloud droplets to earth's surface by turbulence. Big droplets in the initial stage correspond to higher water content, leading to the higher observed value of water content of Xuanen MRF. 展开更多
关键词 mountainous radiation fog fog microphysics upper and middle reaches of the Yangtze river
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A STUDY ON RELATION BETWEEN EAST ASIAN WINTER MONSOON AND CLIMATE CHANGE DURING RAINING SEASON IN CHINA
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作者 晏红明 段玮 肖子牛 《Journal of Tropical Meteorology》 SCIE 2004年第1期23-33,共11页
Based on the data of NCEP, OLR and rainfall of China, we studied the influences of the East Asian winter monsoon activities on the precipitation during the raining season over China by correlation analysis and composi... Based on the data of NCEP, OLR and rainfall of China, we studied the influences of the East Asian winter monsoon activities on the precipitation during the raining season over China by correlation analysis and composite analysis. The result shows that annual and interdecadal change of East Asian winter monsoon is distinct. It is strong from 1950s to the middle of 1980s but weak after the middle of 1980s. The effect of abnormal winter monsoon on the precipitation during raining season is significant over the middle and lower reaches of the Changjiang River basin. It is revealed that the precipitation will increase when preceding winter monsoon is weak but decrease when preceding winter monsoon is strong. In this paper, some appropriate reasons are given to explain the abnormal rainfall by analyzing the distribution of SSTA and the variation of summer circulation. It is pointed out definitely that the variation of SSTA and summer circulation is a primary cause for abnormal rainfall over the middle and lower reaches of the Changjiang River. 展开更多
关键词 East Asian winter monsoon East Asian subtropical summer monsoon summer precipitation over the middle and lower reaches area of the Changjiang river
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数字经济产业区域协同发展机理及路径研究--基于江西与粤港澳、长三角、长江中游城市群协同发展视角 被引量:3
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作者 李小玉 邱信丰 《企业经济》 北大核心 2024年第1期107-116,共10页
数字经济产业区域协同发展对推动区域经济效率变革、质量变革和动力变革具有积极推动作用。近年来,江西充分发挥毗邻粤港澳大湾区、长三角以及位居长江中游城市群的地理优势,积极推动数字经济产业区域协同发展,打造了赣深电子信息产业... 数字经济产业区域协同发展对推动区域经济效率变革、质量变革和动力变革具有积极推动作用。近年来,江西充分发挥毗邻粤港澳大湾区、长三角以及位居长江中游城市群的地理优势,积极推动数字经济产业区域协同发展,打造了赣深电子信息产业集聚区、承接长三角数字产业转移示范区、赣湘电子信息产业园等,为江西数字经济产业高质量发展奠定了扎实基础,但是在数字经济产业区域协同发展过程中仍然存在协同规划缺乏、协同层次偏低、协同结构失衡、产业数字化滞后、数字技术协同创新弱和数据要素共建共享不畅等问题。这需从强化规划引领、提高协同层次、优化协同结构、加快数字化转型、推动数字技术协同创新和促进数据互联互通共用等方面加以破解。 展开更多
关键词 数字经济 协同发展 江西 粤港澳大湾区 长三角 长江中游
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黄河上中游采煤沉陷区水土流失效应的探索与思考 被引量:1
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作者 宋世杰 张家杰 +8 位作者 杨帅 刘志坚 江宁 陈平 刘汉斌 魏江波 刘露 陈宝灯 李源红 《绿色矿山》 2024年第2期169-182,共14页
破解煤炭开采与水土保持之间的矛盾是黄河上中游生态保护与高质量发展的重大科学问题和战略需求。在系统梳理相关研究进展的基础上,指出了“对采煤沉陷区的区域特性认识不充分”、“对采煤沉陷过程中土壤侵蚀关键因子的认识不全面”、... 破解煤炭开采与水土保持之间的矛盾是黄河上中游生态保护与高质量发展的重大科学问题和战略需求。在系统梳理相关研究进展的基础上,指出了“对采煤沉陷区的区域特性认识不充分”、“对采煤沉陷过程中土壤侵蚀关键因子的认识不全面”、“缺少采煤沉陷区不同采动损害类型的土壤侵蚀效应研究”是目前我国煤炭开采区水土流失效应与防控研究存在的主要问题。剖析了黄河上中游7大国家级煤炭基地面临的煤炭开采与水土保持之间的尖锐矛盾及发展趋势。矛盾的焦点主要表现在:第一,煤炭开采集中区与水土流失重点治理区高度重叠导致“能源安全保供”与“水土流失防治”的双重压力;第二,区域自然土壤侵蚀本底导致解决煤炭开采与水土保持矛盾的余地小且难度大;第三,十四五期间持续扩大的采煤沉陷区将成为水土保持攻坚克难的主战场。提出了“地下采动+地下覆岩+地表微地形”耦合下的土壤侵蚀时空演化规律与机理、不同损害类型的土壤侵蚀效应及时空演化规律与机理、构建“地下联合地表”策略下水土流失全生命周期精准防控关键技术体系等是今后黄河上中游采煤沉陷区水土流失效应防控的重点研究方向。希望为破解黄河上中游煤炭开采与水土保持的矛盾,支撑黄河上中游的生态保护与高质量发展提供有益参考。 展开更多
关键词 黄河上中游 采煤沉陷区 水土流失 精准防控 技术路线
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长江中上游重要渔业水域环境质量评估
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作者 吴凡 魏念 +5 位作者 高立方 张燕 茹辉军 吴湘香 倪朝辉 李云峰 《淡水渔业》 CSCD 北大核心 2024年第2期23-33,共11页
为准确评估长江中上游重要渔业水域水环境质量现状及变化趋势,提高水质评价效率,本研究基于11个水质参数,采用水质指数法(water quality index,WQI)对2006-2021年长江中上游三个重要渔业水域水质进行了综合评价,建立WQI min综合评价模... 为准确评估长江中上游重要渔业水域水环境质量现状及变化趋势,提高水质评价效率,本研究基于11个水质参数,采用水质指数法(water quality index,WQI)对2006-2021年长江中上游三个重要渔业水域水质进行了综合评价,建立WQI min综合评价模型。结果显示:(1)长江中上游重要渔业水域的水温和高锰酸盐指数呈上升趋势;基于地表水环境质量标准(GB38338-2002),单因素水质评价结果表明监测水域内整体水质处于地表水Ⅴ类水标准,部分年份达劣Ⅴ类,主要污染指标为总氮。(2)通过综合评价方法分析,长江中上游重要渔业水域整体为“良”;2006~2021年长江中上游重要渔业水域水质质量呈逐年改善的趋势,且上游保护区的改善较大。(3)基于WQI方法,确定了长江中上游重要渔业水域的关键水质参数为:总氮、高锰酸盐指数、汞、溶解氧、氨氮、悬浮物以及水温,分别构建了上游保护区、中华鲟保护区以及四大家鱼保护区的WQI_(min)模型;考虑权重和不考虑权重的WQI min模型对比分析表明,考虑权重的WQI min模型的水质评价结果更加准确,该方法可有效评估长江中上游重要渔业水域的水质变化特征并可扩展用于其他水域。 展开更多
关键词 长江中上游 重要渔业水域 水质指数法 WQI min模型 水质评价
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2013-2022年黑河流域中下游绿洲荒漠区域碳水通量及气象要素观测数据集
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作者 徐自为 刘绍民 +3 位作者 车涛 任志国 谭俊磊 张阳 《中国科学数据(中英文网络版)》 CSCD 2024年第4期364-375,共12页
绿洲-荒漠系统碳水循环的观测和研究对绿洲稳定和可持续发展有重要的意义。本研究以黑河流域中游人工绿洲荒漠和下游天然绿洲荒漠区域为研究对象,基于在该区域建立的12个观测站点,系统整理了2013-2022年11套涡动相关仪、12套自动气象站... 绿洲-荒漠系统碳水循环的观测和研究对绿洲稳定和可持续发展有重要的意义。本研究以黑河流域中游人工绿洲荒漠和下游天然绿洲荒漠区域为研究对象,基于在该区域建立的12个观测站点,系统整理了2013-2022年11套涡动相关仪、12套自动气象站和2组闪烁仪观测获取的碳水通量和气象要素数据。观测项目包括生态系统净碳交换量、蒸散发(潜热通量)、感热通量、空气温度、空气相对湿度、风速、风向、向下/上短波辐射、向下/上长波辐射、净辐射、大气压、降水、红外辐射温度、光合有效辐射、土壤温度与土壤水分廓线、土壤热通量、平均土壤温度等。本数据集经过了严格的数据处理与质量控制,可用于干旱区绿洲荒漠区域生态水文过程、碳水通量变化特征及耦合机制等研究,并为相关模式或遥感产品的真实性检验提供可靠的验证数据。 展开更多
关键词 黑河流域中下游 绿洲荒漠区域 涡动相关仪 自动气象站 闪烁仪
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1951—2020年黄河上中游径流变化特征及归因分析 被引量:4
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作者 孙莉茹 毕华兴 +4 位作者 马志瑾 赵丹阳 王宁 刘泽晖 王鑫 《北京林业大学学报》 CAS CSCD 北大核心 2024年第1期82-92,共11页
【目的】河川径流是地表重要的水资源,对其变化特征和原因进行解析,是流域水资源科学管理规划的前提。【方法】本文采用Mann-Kendall趋势检验、Pettitt突变检验、Budyko弹性系数法等方法分析了黄河上游和中游近70年(1951—2020年)径流... 【目的】河川径流是地表重要的水资源,对其变化特征和原因进行解析,是流域水资源科学管理规划的前提。【方法】本文采用Mann-Kendall趋势检验、Pettitt突变检验、Budyko弹性系数法等方法分析了黄河上游和中游近70年(1951—2020年)径流变化的趋势和成因。【结果】(1)1951—2020年黄河上游年降水量呈不显著增加趋势(4.04 mm/(10 a),P> 0.05),中游呈不显著减少趋势(4.90 mm/(10 a),P> 0.05);上游、中游年潜在蒸散发均呈不显著增加趋势(1.77、2.23 mm/(10 a),P> 0.05);(2)黄河上游和中游1980—2020年土地利用/覆盖变化明显,主要表现在林草面积的增加,上游、中游年NDVI分别以0.025/(10 a)、0.042/(10 a)的速率显著增加(P <0.01);(3)1951—2020年,上游和中游年径流量分别以3.46、7.46 mm/(10 a)的速率显著减少(P <0.01),并分别在1986年、1990年发生突变;(4)上游和中游径流对降水变化最为敏感,其次是土地利用/覆盖变化、潜在蒸散发变化,且径流对各影响因子的敏感性逐年增强,即气候和土地利用/覆盖的变化将更容易引起径流的变化;(5)土地利用/覆盖变化是导致黄河上游和中游径流减少的主要原因,其次是降水和潜在蒸散,但各影响因子对径流变化的影响性质和程度在上游和中游不同区间存在一定的差异。其中,上游地区降水、潜在蒸散发、土地利用/覆盖变化对径流的影响性质和程度分别为-14.04%、1.30%、112.73%;中游地区分别为21.54%、3.63%、74.83%。【结论】1951—2020年黄河上游和中游径流变化是气候变化和土地利用/覆盖变化共同作用的结果,但主要影响因素为人类活动主导的土地利用/覆盖变化,且各因子对径流的影响在不同区间存在一定的差异。本研究结果可为黄河上游和中游不同区间的水资源管理和综合治理提供理论支持。 展开更多
关键词 径流变化 气候变化 土地利用/覆盖变化 Budyko 归因分析 黄河上游和中游
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考虑径流过程矢量化的机器学习洪水预报模型 被引量:2
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作者 刘成帅 解添宁 +4 位作者 李文忠 胡彩虹 徐源浩 牛超杰 余其鹰 《水科学进展》 EI CAS CSCD 北大核心 2024年第3期420-429,共10页
准确的超前洪水预报有利于开展防洪减灾工作和优化水资源调度。本文提出一种针对场次洪水的径流过程矢量化方法(Runoff Process Vectorization, RPV),并耦合3种机器学习(Machine Learning, ML)模型构建了RPV-ML洪水预报系列模型。以黄... 准确的超前洪水预报有利于开展防洪减灾工作和优化水资源调度。本文提出一种针对场次洪水的径流过程矢量化方法(Runoff Process Vectorization, RPV),并耦合3种机器学习(Machine Learning, ML)模型构建了RPV-ML洪水预报系列模型。以黄河中上游孤山川、佳芦河和祖厉河3个典型流域为研究区,分别基于43、28、37场洪水的降雨径流数据,按照洪水场次7∶3的比例进行模型训练和验证。研究表明:(1)相同预见期条件下RPV-ML模型在孤山川、佳芦河和祖厉河流域洪水预报纳什效率系数更高、均方根误差和洪峰相对误差更低,RPV-ML模型比ML模型具有更好的预报性能,在预见期为4~6 h时优势更显著;(2) RPV-ML和ML模型预报精度会随着预见期增加逐渐下降,但RPV-ML预报精度呈现缓慢下降趋势,具有更好的鲁棒性;(3)基于RPV改进的时间卷积网络(Temporal Convolutional Network, TCN)可以更好地克服预报误差问题,RPV-TCN模型在3个流域预报性能最好。 展开更多
关键词 洪水预报 径流过程矢量化 机器学习 RPV-ML模型 黄河中上游
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长江中下游小麦新品系条锈病抗性评估与抗病基因分析
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作者 李壮 黄彦川 +8 位作者 张传量 蔚睿 刘胜杰 吴建辉 李春莲 郑炜君 曾庆东 康振生 韩德俊 《麦类作物学报》 CAS CSCD 北大核心 2024年第7期835-845,共11页
由小麦条锈菌(Puccinia striiformis West. f. sp.tritici Eriks.&Henn.)引起的条锈病是世界范围内小麦的重要病害。长江中下游麦区是中国小麦主产区之一和重要的小麦商品粮基地,也是中国小麦条锈病流行的重点防控地区。准确评价该... 由小麦条锈菌(Puccinia striiformis West. f. sp.tritici Eriks.&Henn.)引起的条锈病是世界范围内小麦的重要病害。长江中下游麦区是中国小麦主产区之一和重要的小麦商品粮基地,也是中国小麦条锈病流行的重点防控地区。准确评价该地区小麦品种(系)对当前小麦条锈病流行小种的抗性,了解抗条锈基因在各个品种及所处麦区内的分布状况,对及时调整抗病育种目标、指导抗病品种及抗病基因的合理布局与应用具有重要意义。本研究收集了2019-2021年间苏、皖、鄂等长江中下游麦区103份小麦材料,包括34份当地主栽品种和69份参加新品种区域审定试验的高代品系,于2021年分别在陕西杨凌混合小种(CYR32、V26-lab)人工病圃及四川江油自然诱发病圃进行成株期抗条锈性鉴定;以当前流行条锈菌小种条中32(CYR32)和G22致病类群(V26-lab)对参鉴品系进行苗期分小种鉴定,利用16个已知抗条锈基因的19个SNP标记进行分子检测,其中包括11个全生育期抗病基因[Yr5a、Yr5b (YrSP)、Yr6、Yr7、Yr9、Yr15、Yr26、Yr28、Yr81、YrZH84和YrAS1676]和5个成株期抗病基因(Yr18、Yr30、Yr78、Yr86和YrLT26),推测小麦品系可能携带的抗病基因。结果表明,34份主栽品种中,23份表现成株期抗病。在69份高代品系中,苗期对CYR32和V26-lab小种表现抗病的品系分别有11份和13份,对CYR32和V26-lab均表现免疫或者近免疫的品系仅有2份。根据品系成株期抗病DS值的聚类热图结果表明,在杨凌表现抗病的品系有44份,在江油表现抗病的品系有25份,在两地均表现环境稳定抗病的品系有17份。分子检测表明,参鉴品系中可能携带Yr5b、Yr6、Yr7、Yr9、Yr30、Yr78、Yr81、Yr86、YrZH84、YrLT26和YrAS1676,其中只有Yr6、Yr81和YrLT26显著影响抗病性,没有发现可能携带Yr5a、Yr15、Yr18、Yr26和Yr28的品系。此外,Yr78、Yr81、Yr86和YrAS1676组合表现可有效抗条锈病。长江中下游麦区小麦品系对小麦条锈菌当前流行小种的抗性整体水平较2010年前明显提高,抗病基因的使用呈多样化趋势。 展开更多
关键词 小麦条锈病 Yr基因 SNP标记 小麦抗条锈育种 长江中下游麦区
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