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1.
Runoff in the source region of a river makes up most of water resources in the whole basin in arid and semi-arid areas. It is very important for water resources management to timely master the latest dynamic changes of the runoff and quantitatively reveal its main driving factors. This paper aims to discover the variation heterogeneity of runoff and the impacts of climatic factors on this runoff in the source region of the Yellow River(SRYR) in China from 1961 to 2016. We divided SRYR into four sub-regions, and analyzed changes of their contributions to total runoff in SRYR. We also revealed the impacts of precipitation, temperature and potential evapotranspiration on runoff in each sub-region by constructing the regression relationships between them at multiple temporal scales. The changes of runoff in the four sub-regions and their contributions to the total runoff were not exactly consistent. The climatic variables’ changes also have heterogeneity, and runoff was mainly affected by precipitation compared to influences of temperature or potential evapotranspiration. Their impacts on runoff have spatiotemporal heterogeneity and can be reflected by very significant-linear regression equations.It provided a simple method to predict headwater runoff for better water management in the whole basin. 相似文献
2.
XINGKexia GUOHuaicheng SUNYanfeng HUANGYongtai 《地理学报(英文版)》2005,15(1):37-43
Water-quality deterioration and eutrophication of the Lake Dianchi have acquired more and more attention in the last few decades. In this paper, the spatial and temporal eutrophication status of the Lake Dianchi was assessed. The comprehensive trophic state index was chosen to assess the trophic status of the Lake Dianchi in the past 13 years. The result reveals that the trophic condition of Caohai is more serious than that of Waihai. Most of time Caohai was in extremely hypereutrophic state from 1988 to 2000. The trophic condition of Waihai had a worsening tendency from 1988 to 2000. Waihai was in eutrophic state before 1995, but it got in a hypereutrophic state after 1995. It was pointed out that TN and TP were the two biggest contributors of CTSIM in both Caohai and Waihai. 相似文献
3.
The Yangtze River is the third largest river in the world and the longest and largest river in China.China has adopted a national strategy to protect the Yangtze River.A better understanding of the ecosystem services value along the Yangtze River would provide support for the Yangtze River protection strategy.Using Costanza’s method to estimate the ecosystem services value,the value of 10 ecosystem services was estimated within 1 km and 2 km from the Yangtze River in 2017.These 10 services were derived from the four established groupings of provisioning,regulating,supporting,and cultural services.This study compared and analyzed the changes in the ecosystem services value in the upper,middle,and lower reaches of the river,and in provinces,cities,and villages along the Yangtze River.The total ecosystem services value within 1 km and 2 km from the river was 37.208 and 43.769 billion yuan,respectively.Within 1 km,the ecosystem services value in the middle reaches was 12.93 billion yuan,while the next highest value was in the upper reaches at 12.45 billion yuan,and the downstream area had the smallest value of 11.855 billion yuan.Within 2 km,the value of upstream ecosystem services was the highest at 16.31 billion yuan,while the second highest value was in the middle reaches at 14.376 billion yuan,and the smallest value was in the downstream area at 13.083 billion yuan.In the Yangtze River Basin,regulating services played a leading role,accounting for 81.6%and 78.9%of the ecosystem services value within 1 km and 2 km from the river,respectively.Among the 10 ecosystem services,hydrological regulation was the most important,while the value of raw material production made the smallest contribution.Among the provinces and cities along the Yangtze River,the highest ecosystem services value was in Hubei Province,while the lowest values were in Shanghai and the Qinghai-Tibet Plateau.If villages within 1 km and 2 km from the river were to be relocated,the total regional ecological value would increase by 527 and 975 million yuan,respectively. 相似文献
4.
《地理学报(英文版)》1999,(2)
PopulationEnvironmentandSustainableDevelopmentareglobalissuesofcrucialimportance.Asisknowntoall,sincethebeginningofthe20thcentury,withtheprogressinscienceandtechnologyaswellasthesharpincreaseinsocialproductivity,humanbeingshavecreatedunprecedentedmaterialwealththatinreturnhasacceleratedtheadvancementofhumancivilization.Atthesametime,problemssuchastheexplosionofpopulation.extravagantconsumptionofenergyandresources,environmentalpollution.andthedestructionoftheecologicalbalance,haveseriouslyimpe… 相似文献
5.
《地理学报(英文版)》1999,(4)
TherehavebeenseveraldozensofyearssincethedevelopmentandstUdyofthemetropolitanareasindevelopedcountries.Atpresent,somemetropolisesaresteppingintothestageofmetropolitandevelopmentinChina.Thegeneraltrendisunavoidablethatbuilt-upareaexpandsandrurallandturnsintourbanones.Butunderthedriveofgoingmerelyaftereconomicbenefit,man}.'collectivesandindividualsillegallyoccupycultivatedlandandgreenbelts,whichintensifiesurbanenvironmentalpollution,wasteslandresourceandmakesthebuilt-upareaexpanduncontrollabl}'… 相似文献
6.
According to climate features and river runoff conditions, Xinjiang could be divided into three research areas: The Altay-Tacheng region, the Tianshan Mountain region and the northern slope of the Kunlun Mountains. Utilizing daily observations from 12 sounding stations and the annual runoff dataset from 34 hydrographical stations in Xinjiang for the period 1960–2002, the variance of the summertime 0℃ level height and the changing trends of river runoff are analyzed both qualitatively and quantitatively, through trend contrast of curves processed by a 5-point smoothing procedure and linear correlation. The variance of the summertime 0℃ level height in Xinjiang correlates well with that of the annual river runoff, especially since the early 1990s, but it differs from region to region, with both the average height of the 0℃ level and runoff quantity significantly increasing over time in the Altay- Tacheng and Tianshan Mountain regions but decreasing on the northern slope of the Kunlun Mountains. The correlation holds for the whole of Xinjiang as well as the three individual regions, with a 0.01 significance level. This indicates that in recent years, climate change in Xinjiang has affected not only the surface layer but also the upper levels of the atmosphere, and this raising and lowering of the summertime 0℃ level has a direct impact on the warming and wetting process in Xinjiang and the amount of river runoff. Warming due to climate change increases the height of the 0℃ level, but also speeds up, ice-snow melting in mountain regions, which in turn increases river runoff, leading to a season of plentiful water instead of the more normal low flow period. 相似文献
7.
Given the importance of waterway depths in river development, the effects of the evolution of bars and troughs on waterway expansion play an important role in river management and water depth conservation. This study aims to expand the waterway dimensions of the Jingjiang Reach of the Yangtze River. To achieve this objective, determining the relationship between river evolution processes and the potential for waterway depth improvement and navigation hindrances is vital. Therefore, the sedimenta... 相似文献
8.
A fossilised paleoanthropological skull was discovered in November 1987, in the guily-head cliff on the east bank of Wenyu River near Xinza village, Yuling - town (hence the name Yuling-Man), Lingbao country, Henan Province, China. The skull, dated to an absolute U-isotope (U234 to U238 ) age of B. P. 156000 ± 13000 years, was found in the upper portion of the alluvial statum of the mid-Pleistocens Series, together with pateoliths of the Kehe Cutture System in the mid-late Paleolithic Periods. Although much research has been nomied out in this area, this is the first fossilised paleoanthropological skull in have been found. Therefore, this project, funded by the Natural Science Foundation/Henan Scientific Committee, is making new contributions to paleoanthropological research in China. 相似文献
9.
A study of the contribution of mass elevation effect to the altitudinal distribution of timberline in the Northern Hemisphere简 总被引：3，自引：0，他引：3
Alpine timberline, as the ＂ecologica tion of scientists in many fields, especially in transition zone,＂ has long attracted the atten- recent years. Many unitary and dibasic fitting models have been developed to explore the relationship between timberline elevation and latitude or temperature. However, these models are usually on regional scale and could not be applied to other regions; on the other hand, hemispherical-scale and continental-scale models are usually based on about 100 timberline data and are necessarily low in precision. The present article collects 516 data sites of timberline, and takes latitude, continentality and mass elevation effect （MEE） as independent variables and timberline elevation as dependent variable to develop a ternary linear regression meteorological data released by WorldClim and model. Continentality is calculated using the mountain base elevation （as a proxy of mass elevation effect） is extracted on the basis of SRTM 90-meter resolution elevation data. The results show that the coefficient of determination （R2） of the linear model is as high as 0.904, and that the contribution rate of latitude, continentality and MEE to timberline elevation is 45.02% （p=0.000）, 6.04% （p=0.000） and 48.94% （p=0.000）, respectively. This means that MEE is simply the primary factor contributing to the elevation distribution of timberline on the continental and hemispherical scales. The contribution rate of MEE to timberline altitude dif- fers in different regions, e.g., 50.49% （p=0.000） in North America, 48.73% （p=0.000） in the eastern Eurasia, and 43.6% （p=0.000） in the western Eurasia, but it is usually very high. 相似文献
10.
YANGOing CUICaixia 《地理学报(英文版)》2005,15(1):20-28
To reveal the changing trend and annual distribution of the surface water hydrology and the local climate in the Bayanbuluk alpine-cold wetlands in the past 50 years, we used temperature, precipitation, different rank precipitation days, evaporation, water vapor pressure, relative humidity, dust storm days and snow depth to analyze their temporal variations. We conclude that there were no distinct changes in annual mean temperature, and no obvious changes in the maximum or minimum temperatures. Precipitation in warm season was the main water source in the wetlands of the study area and accounted for 92.0% of the annual total. Precipitation dropped to the lowest in the mid-1980s in the past 50 years and then increased gradually. The runoff of the Kaidu River has increased since 1987 which has a good linear response to the annual precipitation and mean temperature in Bayanbuluk alpine-cold wetland. Climate change also affected ecosystems in this area due to its direct relations to the surface water environment. 相似文献
11.
Elucidating the distribution of the grazing pressure requires an understanding of the grazing activities. In this study, we analyzed the grazing behavior of yaks in Three-RiverSource Region(TRSR) and identified the main factors influencing the distribution of grazing intensity(GI) using trajectory data and remote sensing datasets. Our results revealed that a semi-resident transhumance strategy is employed in this region. The average grazing time(GT) of four GPS collars over the year was 11.84 h/... 相似文献
12.
TANG Guo-an~ Josef Strobl~ GONG Jian-ya~ ZHAO Mu-dan~ CHEN Zhen-jiang~ 《地理学报(英文版)》2001,11(2):209-216
1 IntroductionDigital elevation model (DEM) is digital representation of relief. It is one of the most important components in the database of GIS. At present, DEM is playing a key role in the field of survey and mapping, remote sensing and almost all the terrain related geographical analyses. DEM can be grouped into regular grids (raster) and triangulated irregular networks (TIN). Both have their advantages and disadvantages in application. It is generally believed that grid DEM will … 相似文献
13.
Pollution characteristics of the rivers in suburban Shanghai 总被引：1，自引：0，他引：1
Forty middle and small rivers in three towns of Fengjing, Songjiang and Zhujiajiao of suburban Shanghai were chosen as sampling sites for water quality research. Measurement results of DO, CODCr, TP, TN and so on show that the rivers are under heavy eutropic conditions, which are several times greater than the critical values of the worst level (Type V) of water. Water pollution situation has different temporal and spatial characteristics. Non-point pollution, such as village domestic sewage, farmland runoff, livestock feces, has become the primary source of pollution of the middle and small rivers in suburban Shanghai. 相似文献
14.
ZHANGBai ZHANGShuqing WANGAihua ZHANGJunyan 《地理学报(英文版)》2003,13(2):201-207
Using the methods of combining landscape ecology with GIS spatial analysis,this paper analyses the dynamics of the marsh landscape stucture of the Sanjing Plain in the past 20 years,furthermore,taking Fujin County,located in the north of the plain,as an example,analyzes the conversion between marsh and other land use types.It is shown that the marsh in the Sanjiang Plain decreased greatly in the past 20 years,but the trend has begun to reverse,The marsh area decreased by 51.33% from 1980 to 1996,whereas it decreased by 4.19% from 1996 to 2000.The fragmentation of the marsh increased;the number of the patches increased by 326 from 1986 to 1996,whereas it only increased by 18 patches from 1996 to 2000,It is obvious that the speed of patches number diminished and the marsh fragmentation decreased,which shows that the reclamation of the marsh converted from the fragmentation to the brim in a large area of the marsh.The reclaimed marsh has mainly converted to paddy field and dry land .Large area of the marsh.The reclaimed marsh has mainly converted to paddy fiedld and dry land.Large-scale reclamation in the Sanjiang Plain influences its natural environment directly:the climate of the region turns from cold and wet to warm and dry,which makes the marsh both in the low-temperature northern part and in the deeply stagnant eastern part suitable for further agricultural development. 相似文献
15.
Wind tunnel simulation of the effects of freeze–thaw cycles on soil erosion in the Qinghai–Tibet Plateau 总被引：1，自引：1，他引：0
Intense freezing and thawing actions occur in the Qinghai–Tibet Plateau because of its high elevation and cold temperature. The plateau's unique environment makes it easy to generate wind erosion under dry, windy weather conditions, resulting in the emergence of desertification. As a major form of freeze–thaw erosion, freeze–thaw and wind erosion is displayed prominently on the Qinghai–Tibet Plateau. Therefore, in this study, soil samples were collected from the surface of the plateau to undergo freeze–thaw and wind erosion simulation experiments. Results show that wind erosion strength increases with an increasing number of freeze–thaw cycles, water content in the freezing–thawing process, and the difference in freeze–thaw temperatures. Therefore, in the conditions of water participation, the main reason for the freeze–thaw and wind erosion in the Qinghai–Tibet Plateau is the damage to the soil structure by repeated, fierce freeze–thaw actions, and the sand-bearing wind is the main driving force for this process. The research results have theoretical significance for exploring the formation mechanism of freeze–thaw and wind erosion in the Qinghai–Tibet Plateau, and provide a scientific basis for freeze–thaw desertification control in the plateau. 相似文献
16.
Delayed response behaviour commonly occurs in conjunction with changes in riverbed scouring and sediment deposition and is a key component in understanding the intrinsic behaviour of reservoir siltation. Due to the complexity of the riverbed siltation process, the variability in the factors that influence siltation and the limitations of available research methods, the understanding of the delayed response behaviour of the sedimentation process in the Three Gorges Reservoir(TGR) is currently mer... 相似文献
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18.
JI Zhengxin LIU Chao XU Yueqing SUN Minxuan WEI Hejie SUN Danfeng LI Yaoyao ZHANG Ping SUN Qiangqiang 《地理学报(英文版)》2023,33(4):779-800
Developed here is an integrated framework for identifying production–living–ecological space(PLES) quantitatively at grid scale from the perspective of multifunction land use, and 25 compound space types are classified to highlight the multiple functions of PLES. As a typical mountainous city in northern Hebei province, Zhangjiakou is used as a case study, and the results show that more than 80% of the land space in Zhangjiakou has remarkable triple functionality. The living-dominated space and ... 相似文献
19.
S.Ting 《地理学报(英文版)》1947,(2)
In May 1945, the author flew to Urumuchi vis the Kansu Corridor. There are evidently streamflood cournes on the no 'thern front the Chilienshan and great pediments have been formed. Former erosional surface on the Chilienshan were seen in two localities. They ars well preserved flat-topped benches sloping towards the north; and flanked by gullies, These lie at the altitude 3,200 meters above the sea. 相似文献
20.
In May 1945, the author flew to Urumuchi vis the Kansu Corridor. There are evidently streamflood cournes on the no 'thern front the Chilienshan and great pediments have been formed. Former erosional surface on the Chilienshan were seen in two localities. They ars well preserved flat-topped benches sloping towards the north; and flanked by gullies, These lie at the altitude 3,200 meters above the sea. 相似文献