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Characterization of saline soil for the halophytes of largest inland saline wetland of India using geospatial technology
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作者 Naik RAJASHREE Sharma LAXMI KANT Singh AVINASH 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1277-1291,共15页
About 23%of the surface area and 44%of the volume of all the lakes are occupied by saline lakes in the world.Importantly,agricultural diversion,illegal encroachment,pollution,and invasive species could cause these lak... About 23%of the surface area and 44%of the volume of all the lakes are occupied by saline lakes in the world.Importantly,agricultural diversion,illegal encroachment,pollution,and invasive species could cause these lakes to dry up completely or partially by 2025.Illegal saltpan encroachment is causing Sambhar,India’s largest saline lake,to shrink by 4.23%every decade.This study aims to characterize the soil parameters where halophytes are growing.A literature survey was conducted for halophytes and soil characteristics.The study area was divided into four zones for stratified random sampling.Soil sampling was conducted in February 2021.The soil indicators for halophyte selected were pH,electrical conductivity,moisture,salinity,organic carbon,and organic matter.The obtained results were interpolated in the geospatial platform for soil characteristic mapping.It is found that no research is conducted on halophytes of the lake.Studies on soil are also inconsistent and only six common parameters could be identified.Results show that the pH ranged 9.37-7.66,electrical conductivity was 16.1-0.38,moisture 23.37%-1.2%,organic carbon 3.29%-0.15%,organic matter 5.6%-0.2%,and salinity 8.86%-0.72%.Though these results show improved condition as compared to last few years,in long term,the lake is desiccating.During the UN Decade of Ecosystem Restoration(2021-2030),if these causes are not addressed,the ecosystem may completely dry up. 展开更多
关键词 HALOPHYTES inland lakes saline wetlands soil geospatial mapping interpolation
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Modelling Dry Port Systems in the Framework of Inland Waterway Container Terminals
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作者 Milovan Kovac Snezana Tadic +1 位作者 Mladen Krstic Violeta Roso 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期1019-1046,共28页
Overcoming the global sustainability challenges of logistics requires applying solutions that minimize the negative effects of logistics activities.The most efficient way of doing so is through intermodal transportati... Overcoming the global sustainability challenges of logistics requires applying solutions that minimize the negative effects of logistics activities.The most efficient way of doing so is through intermodal transportation(IT).Current IT systems rely mostly on road,rail,and sea transport,not inland waterway transport.Developing dry port(DP)terminals has been proven as a sustainable means of promoting and utilizing IT in the hinterland of seaport container terminals.Conventional DP systems consolidate container flows from/to seaports and integrate road and rail transportation modes in the hinterland which improves the sustainability of the whole logistics system.In this article,to extend literature on the sustainable development of different categories of IT terminals,especially DPs,and their varying roles,we examine the possibility of developing DP terminals within the framework of inland waterway container terminals(IWCTs).Establishing combined road–rail–inland waterway transport for observed container flows is expected to make the IT systems sustainable.As such,this article is the first to address the modelling of such DP systems.After mathematically formulating the problem of modelling DP systems,which entailed determining the number and location of DP terminals for IWCTs,their capacity,and their allocation of container flows,we solved the problem with a hybrid metaheuristic model based on the Bee Colony Optimisation(BCO)algorithmand themeasurement of alternatives and ranking according to compromise solution(i.e.,MARCOS)multi-criteria decision-making method.The results from our case study of the Danube region suggest that planning and developingDP terminals in the framework of IWCTs can indeed be sustainable,as well as contribute to the development of logistics networks,the regionalisation of river ports,and the geographic expansion of their hinterlands.Thus,the main contributions of this article are in proposing a novel DP concept variant,mathematically formulating the problems of its modelling,and developing an encompassing hybrid metaheuristic approach for treating the complex nature of the problem adequately. 展开更多
关键词 Dry port intermodal transport terminal SUSTAINABILITY Bee Colony Optimization MARCOS inland waterway transport
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The changes in the annual distribution of mountain runoff during the period of 1965-2018 in Hexi Corridor,Northwest China
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作者 Yan Luo ZhiXiang Lu +2 位作者 Qi Feng Meng Zhu JinBo Zhang 《Research in Cold and Arid Regions》 CSCD 2024年第2期73-83,共11页
The annual distribution characteristics of river runoff in arid regions have significant implications for water resource stability and management.Based on the mountain runoff data from 1965 to 2018,this study examines... The annual distribution characteristics of river runoff in arid regions have significant implications for water resource stability and management.Based on the mountain runoff data from 1965 to 2018,this study examines the annual change characteristics of monthly runoff of the Shiyang River Basin,Heihe River Basin,and Shule River Basin in the Hexi Corridor,Northwest China.Many indexes are used and analyzed,including the coefficient of variance,the complete regulation coefficient,the concentration degree and concentration period,the magnitude of change,the skewness coefficient,and the kurtosis coefficient of the annual distribution curves.The results reveal the following:(1)The inhomogeneity of annual runoff distribution in the Taolai River and the rivers to the west of it,except the Shiyou River,show an increasing trend.Conversely,the inhomogeneity of the rivers to the east of the Taolai River generally show a downward trend,but the coefficient of variance value is still very high.(2)In the Shiyang River Basin,the annual distribution of the concentration period is characterized by a relatively discrete pattern.Conversely,the Heihe River Basin exhibits a relatively concentrated pattern,and the distribution pattern of the Shule River Basin is quite different.Notably,all concentration periods in the three basins have shifted backward after the 2000s.(3)The Shiyang River Basin exhibits disordered annual distribution curves of runoff in different years.In contrast,the Heihe River Basin presents a typical‘single-peak’pattern with a prominent right-skewed.The Shule River Basin has regular distribution curves,with a gradually significant‘double-peak’pattern from east to west.Overall,there has been a slight change in runoff in the Shiyang River Basin,while the Heihe River Basin and Shule River Basin have experienced significant increases in runoff.The annual distribution curves of runoff in the Liyuan River and the rivers to the east of it exhibit a gentle peak pattern,and the appearance probability of extreme runoff during the year is low.Conversely,the rivers to the west of the Liyuan River,excluding the Danghe River,display a sharp peak and thick tail pattern,indicating that the appearance probability of extreme runoff during the year is high.These findings have practical implications for the planning and management of water resources in the Hexi Corridor.Moreover,they provide a solid foundation for predicting future changes in regional water resources. 展开更多
关键词 Hexi Corridor inland rivers Mountain runoff Annual distribution characteristics of runoff
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The Miracle of Hefei:From Small to Smart
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作者 FU ZHAOHUAN HUA MING 《China Today》 2024年第8期32-34,共3页
The tale of an inconspicuous inland city gathering a thriving cluster of dynamic tech-intensive industries.MODERNIZING the industrial system and developing new quality productive forces at a faster pace-this is one of... The tale of an inconspicuous inland city gathering a thriving cluster of dynamic tech-intensive industries.MODERNIZING the industrial system and developing new quality productive forces at a faster pace-this is one of China’s major tasks for 2024 as laid down in the Report on the Work of the Government. 展开更多
关键词 GAtheRING inland FASTER
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Function Evolution and Landscape Planning Strategy of Inland Rivers in Beilun Port City of Ningbo
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作者 ZHONG Guoqing 《Journal of Landscape Research》 2024年第1期12-16,21,共6页
In the history, the main roles of inland rivers in Beilun Port City of Ningbo were desalination,blocking tides, shipping, and flood control. Nowadays, with the continuous spread and deepening ofurbanization, the ecolo... In the history, the main roles of inland rivers in Beilun Port City of Ningbo were desalination,blocking tides, shipping, and flood control. Nowadays, with the continuous spread and deepening ofurbanization, the ecological environment of river courses has been destroyed. In the past, remediationmeasures based on engineering and technology played a certain role, but can not “cure the root cause”. Itshould respect the historical evolution process of river courses, and highlight the ecological service functionand leisure tourism value of river courses from the coordination perspective of urban and rural ecologicalenvironment, economic industries, society and culture in the planning ideas of ecology, production, andlife integration. Four aspects of the measures are as below: protecting and repairing the ecological matrixof river courses;building green space system and maintaining flood control functions through the waternetwork;protecting cultural heritage along the rivers;developing waterfront leisure tourism scenic area. 展开更多
关键词 Beilun Port City inland river Function evolution Landscape planning
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Impact of climate change and human activities on the spatiotemporal dynamics of surface water area in Gansu Province, China
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作者 LU Haitian ZHAO Ruifeng +3 位作者 ZHAO Liu LIU Jiaxin LYU Binyang YANG Xinyue 《Journal of Arid Land》 SCIE CSCD 2024年第6期798-815,共18页
Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with comp... Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with complex terrain and variable climate,as the research subject.Based on Google Earth Engine,we used Landsat data and the Open-surface Water Detection Method with Enhanced Impurity Control method to monitor the spatiotemporal dynamics of surface water area in Gansu Province from 1985 to 2022,and quantitatively analyzed the main causes of regional differences in surface water area.The findings revealed that surface water area in Gansu Province expanded by 406.88 km2 from 1985 to 2022.Seasonal surface water area exhibited significant fluctuations,while permanent surface water area showed a steady increase.Notably,terrestrial water storage exhibited a trend of first decreasing and then increasing,correlated with the dynamics of surface water area.Climate change and human activities jointly affected surface hydrological processes,with the impact of climate change being slightly higher than that of human activities.Spatially,climate change affected the'source'of surface water to a greater extent,while human activities tended to affect the'destination'of surface water.Challenges of surface water resources faced by inland arid and semi-arid areas like Gansu Province are multifaceted.Therefore,we summarized the surface hydrology patterns typical in inland arid and semi-arid areas and tailored surface water'supply-demand'balance strategies.The study not only sheds light on the dynamics of surface water area in Gansu Province,but also offers valuable insights for ecological protection and surface water resource management in inland arid and semi-arid areas facing water scarcity. 展开更多
关键词 surface water area terrestrial water storage Open-surface Water Detection Method with Enhanced Impurity Control method Google Earth Engine climate change human activities inland arid and semi-arid areas
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Zones of Openness China’s reforms in its free trade zones offer opportunities to the world
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作者 ZHAO ZHONGXIU KONG QINGFENG ZHU YONGBIAO 《ChinAfrica》 2024年第8期24-25,共2页
Since the 18th National Congress of the Communist Party of China held in 2012,the construction of pilot free trade zone has emerged as a strategically important approach for China’s reform and opening up efforts.Thes... Since the 18th National Congress of the Communist Party of China held in 2012,the construction of pilot free trade zone has emerged as a strategically important approach for China’s reform and opening up efforts.These zones exemplify China’s proactive and open strategy,serving as a key driver for promoting high-quality development.In September 2013,China launched its first pilot free trade zone,China(Shanghai)Pilot Free Trade Zone.Over the past decade,21 additional pilot free trade zones have been established across the country.This expansion has created a comprehensive reform and opening up innovation agenda that spans the eastern,western,southern,northern,and central regions,while integrating coastal,inland,and border areas. 展开更多
关键词 Zone inland integrating
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SUSTAINABLE EXPLOITATION AND UTILIZATION OF WATER RESOURCES IN THE INLAND RIVERBASIN OF ARID NORTHWEST CHINA 被引量:12
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作者 马金珠 《Chinese Geographical Science》 SCIE CSCD 1997年第4期347-351,共5页
Calculated in terms of surface runoff plus irrepeated groundwater, there is about 8. 67 ×1010m3 of total available water resources in the inland river basins of arid Northwest China. Water resources is the decisi... Calculated in terms of surface runoff plus irrepeated groundwater, there is about 8. 67 ×1010m3 of total available water resources in the inland river basins of arid Northwest China. Water resources is the decisive factor for survival of oases and human being. But there have arisen several aspects of Serious eco-environment problems resulted from irrational exploitation and utilization. From now on, the development and utilization of water not only requires to promote regional economy, but also needs to protect and improve the environment based on their potential. Sustainable utilization needs to broaden new sources and saving water at first. Then three measures are recommended. 展开更多
关键词 water RESOURCES sustainable EXPLOITATION and utilization inland river BASIN
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Hydrological and water cycle processes of inland river basins in the arid region of Northwest China 被引量:13
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作者 CHEN Yaning LI Baofu +2 位作者 FAN Yuting SUN Congjian FANG Gonghuan 《Journal of Arid Land》 SCIE CSCD 2019年第2期161-179,共19页
The increasing shortage in water resources is a key factor affecting sustainable socio-economic development in the arid region of Northwest China(ARNC). Water shortages also affect the stability of the region's oa... The increasing shortage in water resources is a key factor affecting sustainable socio-economic development in the arid region of Northwest China(ARNC). Water shortages also affect the stability of the region's oasis ecosystem. This paper summarizes the hydrological processes and water cycle of inland river basins in the ARNC, focusing on the following aspects: the spatial-temporal features of water resources(including air water vapor resources, runoff, and glacial meltwater) and their driving forces; the characteristics of streamflow composition in the inland river basins; the characteristics and main controlling factors of baseflow in the inland rivers; and anticipated future changes in hydrological processes and water resources. The results indicate that:(1) although the runoff in most inland rivers in the ARNC showed a significant increasing trend, both the glaciated area and glacial ice reserves have been reduced in the mountains;(2) snow melt and glacier melt are extremely important hydrological processes in the ARNC, especially in the Kunlun and Tianshan mountains;(3) baseflow in the inland rivers of the ARNC is the result of climate change and human activities, with the main driving factors being the reduction in forest area and the over-exploitation and utilization of groundwater in the river basins; and(4) the contradictions among water resources, ecology and economy will further increase in the future. The findings of this study might also help strengthen the ecological, economic and social sustainable development in the study region. 展开更多
关键词 water resources climate change RIVER runoff BASEFLOW streamflow composition inland RIVER basin ARID region of NORTHWEST China
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Climate effects on an inland alpine lake in Xinjiang, China over the past 40 years 被引量:7
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作者 HuiXia CHAI WeiMing CHENG +2 位作者 ChengHu ZHOU ShangMin ZHAO HaiJiang LIU 《Journal of Arid Land》 SCIE CSCD 2013年第2期188-198,共11页
Inland lakes are important water resources in arid and semiarid regions. Understanding climate effects on these lakes is critical to accurately evaluate the dynamic changes of water resources. This study focused on th... Inland lakes are important water resources in arid and semiarid regions. Understanding climate effects on these lakes is critical to accurately evaluate the dynamic changes of water resources. This study focused on the changes in Sayram Lake of Xinjiang, China, and addressed the effects of climate fluctuations on the inland lake based on long-term sequenced remote sensing images and meteorological data from the past 40 years. A geo- graphic information system (GIS) method was used to obtain the hypsometry of the basin area of Sayram Lake, and estimation methods for evaporation from rising temperature and water levels from increasing precipitation were proposed. Results showed that: (1)Areal values of Sayram Lake have increased over the past 40 years. (2) Both temperature and precipitation have increased with average increases of more than 1.8~C and 82 mm, respectively. Variation of the water levels in the lake was consistent with local climate changes, and the areal values show linear relationships with local temperature and precipitation data. (3) According to the hypsometry data of the basin area, the estimated lake water levels increased by 2.8 m, and the water volume increased by 12.9×108 m3 over the past 40 years. The increasing area of Sayram Lake correlated with local and regional climatic changes because it is hardly affected by human activities. 展开更多
关键词 Sayram Lake climate change water body extraction areal variation inland alpine lake
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Simulation of hydrological processes of mountainous watersheds in inland river basins: taking the Heihe Mainstream River as an example 被引量:7
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作者 ZhenLiang YIN HongLang XIAO +4 位作者 SongBing ZOU Rui ZHU ZhiXiang LU YongChao LAN YongPing SHEN 《Journal of Arid Land》 SCIE CSCD 2014年第1期16-26,共11页
The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the ... The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the mountainous watershed of the Heihe Mainstream River as a study area to simulate the hydrological processes of mountainous watersheds in inland river basins by using the soil and water assessment tool(SWAT)model.SWAT simulation results show that both the Nash–Sutcliffe efficiency and the determination coefficient values of the calibration period(January 1995 to December 2002)and validation period(January 2002 to December 2009)are higher than 0.90,and the percent bias is controlled within±5%,indicating that the simulation results are satisfactory.According to the SWAT performance,we discussed the yearly and monthly variation trends of the mountainous runoff and the runoff components.The results show that from 1996 to 2009,an indistinctive rising trend was observed for the yearly mountainous runoff,which is mainly recharged by lateral flow,and followed by shallow groundwater runoff and surface runoff.The monthly variation demonstrates that the mountainous runoff decreases slightly from May to July,contrary to other months.The mountainous runoff is mainly recharged by shallow groundwater runoff in January,February,and from October to December,by surface runoff in March and April,and by lateral flow from May to September. 展开更多
关键词 hydrological process mountainous runoff inland river basin soil and water assessment tool the Heihe Mainstream River
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An Abrupt Rainfall Decrease over the Asian Inland Plateau Region around 1999 and the Possible Underlying Mechanism 被引量:8
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作者 Jinling PIAO Wen CHEN +4 位作者 Ke WEI Yong LIU Hans-F.GRAF Joong-Bae AHN Alexander POGORELTSEV 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第4期456-468,共13页
A decadal change in summer rainfall in the Asian inland plateau(AIP) region is identified around 1999. This decadal change is characterized by an abrupt decrease in summer rainfall of about 15.7% of the climatologic... A decadal change in summer rainfall in the Asian inland plateau(AIP) region is identified around 1999. This decadal change is characterized by an abrupt decrease in summer rainfall of about 15.7% of the climatological average amount,leading to prolonged drought in the Asian inland plateau region. Both the surface air temperature and potential evapotranspiration in the AIP show a significant increase, while the soil moisture exhibits a decrease, after the late 1990s. Furthermore,the normalized difference vegetation index shows an apparent decreasing trend during 1999–2007. Three different drought indices—the standardized precipitation index, the standardized precipitation evapotranspiration index, and the self-calibrating Palmer drought severity index—present pronounced climate anomalies during 1999–2007, indicating dramatic drought exacerbation in the region after the late 1990s. This decadal change in the summer rainfall may be attributable to a wave-like teleconnection pattern from Western Europe to Asia. A set of model sensitivity experiments suggests that the summer warming sea surface temperature in the North Atlantic could induce this teleconnection pattern over Eurasia, resulting in recent drought in the AIP region. 展开更多
关键词 Asian inland plateau summer rainfall drought teleconnection pattern North Atlantic
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THE RELATIONSHIP BETWEEN INLAND LAKES EVOLUTION AND CLIMATIC FLUCTUATION IN ARID ZONE 被引量:1
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作者 秦伯强 施雅风 王苏民 《Chinese Geographical Science》 SCIE CSCD 1991年第4期26-33,共8页
The evolution of the inland lakes in arid and semi-arid zones is accorded with the climatic fluctuation. The humid climate is in harmony with the higher water level and greater lake water quantity budget while arid cl... The evolution of the inland lakes in arid and semi-arid zones is accorded with the climatic fluctuation. The humid climate is in harmony with the higher water level and greater lake water quantity budget while arid climate is in correspondence with the lower water level and little water budget. Based on the analysis of the lake fluctuation and lake budget change, with the aid of the data of geom’orphology, palynology, sedimentology and chronology, It is found that the climate experienced a warm and humid period during 7000-3500 yr. B. P. and showed a drying and warming trend in the last century in the Central Asia. 展开更多
关键词 CLIMATIC FLUCTUATION inland LAKES lake EVOLUTION ARID zone
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Air–water CO2 flux in an algae bloom year for Lake Hongfeng,Southwest China:implications for the carbon cycle of global inland waters 被引量:8
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作者 Faxiang Tao 《Acta Geochimica》 EI CAS CSCD 2017年第4期658-666,共9页
The carbon cycle of global inland waters is quantitatively comparable to other components in the global carbon budget. Among inland waters, a significant part is man-made lakes formed by damming rivers. Manmade lakes ... The carbon cycle of global inland waters is quantitatively comparable to other components in the global carbon budget. Among inland waters, a significant part is man-made lakes formed by damming rivers. Manmade lakes are undergoing a rapid increase in number and size. Human impacts and frequent algae blooms lead to it necessary to make a better constraint on their carbon cycles. Here, we make a primary estimation on the air–water CO_2 transfer flux through an algae bloom year for a subtropical man-made lake—Hongfeng Lake, Southwest China. To do this a new type of glass bottles was designed for content and isotopic analysis of DIC and other environmental parameters. At the early stage of algae bloom,CO_2 was transferred from the atmosphere to the lake with a net flux of 1.770 g·C·m^(-2). Later, the partial pressure(pCO_2) of the aqueous CO_2 increased rapidly and the lake outgassed to the atmosphere with a net flux of 95.727 g·C·m^(-2). In the remaining days, the lake again took up CO_2 from the atmosphere with a net flux of 14.804 g·C·m^(-2). As a whole, Lake Hongfeng released 4527 t C to the atmosphere, accounting for one-third of the atmosphere/soil CO_2 sequestered by chemical weathering in the whole drainage. With an empirical mode decomposition method, we found air temperature plays a major role in controlling water temperature, aqueous pCO_2 and hence CO_2 flux. This work indicates a necessity to make detailed and comprehensive carbon budgets in man-made lakes. 展开更多
关键词 CO2 flux Algae bloom Carbon cycle inland waters Lake Hongfeng
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Study of temperature and precipitation change in upstream mountain area of the Hexi inland river basin since 1960s 被引量:4
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作者 YongChao Lan HongLang Xiao +4 位作者 XingLin Hu HongWei Ding SongBing Zou ChengFang La Jie Song 《Research in Cold and Arid Regions》 2012年第6期522-535,共14页
All rivers in the Hexi inland region of Gansu Province, China, originate from the northern slope of the Qilian Mountains. They are located in the southern portion of the region and respectively belong to the three lar... All rivers in the Hexi inland region of Gansu Province, China, originate from the northern slope of the Qilian Mountains. They are located in the southern portion of the region and respectively belong to the three large river systems from east to west, the Shiyang, Heihe and Shule river basins. These rivers are supplied by precipitation, snowmelt and ice-melt runoff from the Qilian Mountain area. Therefore, changes of precipitation and temperature in the upstream watersheds of these rivers have an important effect on changes of mountainous runoff and reasonable utilization of water resources in this region. For this reason, the Qilian Mountain area, upstream watersheds and runoff forming areas of these rivers are chosen as the study area. The change characteristics and variation trend of temperature and precipitation in this area under the backdrop of global warming axe analyzed based on observa- tional data of relational weather and hydrologic stations in the area. Results show that temperatures in the upriver mountain areas of these three large river basins have been increasing, although the increasing degree is differentially affected by global warming. The rising extent of annual and seasonal temperatures in the upstream mountain area of the Shule river basin located in the west- em Qilian Mountains, were all largest over the past 50 years. Precipitation in the upstream mountain areas of Hexi region' three river basins located respectively in the western, middle and eastern Qilian Mountains have been presenting an increasing trend to varying degrees as a whole for more than 50 years. This means that climate in the upstream mountain areas of Hexi region' three river basins are becoming increasingly warmer and moister over the past 50 years, which will be very good for the ecological en- vironment and agricultural production in the region. 展开更多
关键词 global warming upstream mountain area Qilian Mountains three large fiver systems Hexi inland fiver basin
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THE HYDROLOGICAL EFFECT UNDER HUMAN ACTIVITIESIN THE INLAND WATERSHEDS OF XINJIANG, CHINA 被引量:2
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作者 LI Xin, JI Fang, ZHOU Hong-fei (Xinjiang Institute of Ecology and Geography, the Chinese Academy of Sciences, Urumqi 830011, P. K China) 《Chinese Geographical Science》 SCIE CSCD 2001年第1期27-34,共8页
Natural environment, inland water distribution and water circulation has been changed greatly affected by human activities in Xinjiang, China. Human activities developed quickly in the inland watersheds in Xinjiang af... Natural environment, inland water distribution and water circulation has been changed greatly affected by human activities in Xinjiang, China. Human activities developed quickly in the inland watersheds in Xinjiang after 1950. More than 50% of river water is drawn into irrigation area, and all water in parts of little river is drawn to canal or reservoirs. However, there is evident hydrological effect caused by human activities. 1) water distribution in arid land has changed. A lot of river water is drawn into oasis and water table inside of oasis has risen but declined out of oasis. However, water table has declined in some cities because of over pumping for groundwater. 2) Stream process has changed after water drawing and drainage for irrigation. Runoff in the lower reaches of river has generally decreased, and the lower reaches of some rivers are even disappeared for stream. 3) Large watersheds have been divided into several small watersheds. In some tributaries, most of the river water has drawn to irrigation area so that stream in the lower reaches has disappeared for years. 4) Evaporation at oasis has increased from 50–200mm/a to 800–1300mm/a after reclamation. But it decreased to 50mm/a or less out of oasis. Some lakes have reduced or dried. Water-system with canals and reservoirs has appeared in the oases. 5) Water quality of inland rivers and lakes has generally deteriorated because it accepts drainage water from farmland and factories. 6) Effective scale of human activities on hydrological process in arid land has expanded from separate rivers to all watersheds; from surface water to groundwater; from drought season to flood season; and from single year to several years. Scale of the effect of human activities to hydrological process is going larger and larger. Along with the effective usage of water resources in the inland watershed in Xinjiang, the hydrological effect of human activities will be mainly change to: 1) river in pain area will be canalized; 2) stream process will be controlled by human being; 3) lakes in plain area will degenerate; 4) water will be salty in the lower reaches of river. However, hydrological conditions in Xinjiang will be better to water using and to natural environment. 展开更多
关键词 XINJIANG inland rivers human activities hydrological effects
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Soil Carbon, Nitrogen and Phosphorus Concentrations and Stoichiometries Across a Chronosequence of Restored Inland Soda Saline-Alkali Wetlands, Western Songnen Plain, Northeast China 被引量:5
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作者 YANG Yanli MOU Xiaojie +1 位作者 WEN Bolong LIU Xingtu 《Chinese Geographical Science》 SCIE CSCD 2020年第5期934-946,共13页
Soil carbon(C), nitrogen(N) and phosphorus(P) concentrations and stoichiometries can be used to evaluate the success indicators to the effects of wetland restoration and reflect ecosystem function. Restoration of inla... Soil carbon(C), nitrogen(N) and phosphorus(P) concentrations and stoichiometries can be used to evaluate the success indicators to the effects of wetland restoration and reflect ecosystem function. Restoration of inland soda saline-alkali wetlands is widespread, however, the soil nutrition changes that follow restoration are unclear. We quantified the recovery trajectories of soil physicochemical properties, including soil organic carbon(SOC), total nitrogen(TN), and total phosphorus(TP) pools, for a chronosequence of three restored wetlands(7 yr, 12 yr and 21 yr) and compared these properties to those of degraded and natural wetlands in the western Songnen Plain, Northeast China. Wetland degradation lead to the loss of soil nutrients. Relative to natural wetlands, the mean reductions of in SOC, TN, and TP concentrations were 89.6%, 65.5% and 52.5%, respectively. Nutrients recovered as years passed after restoration. The SOC, TN, and TP concentrations increased by 2.36 times, 1.15 times, and 0.83 times, respectively in degraded wetlands that had been restored for 21 yr, but remained 29.2%, 17.3%, and 12.8% lower, respectively, than those in natural wetlands. The soil C∶N(RC N), C∶P(R CP), and N∶P(R NP) ratios increased from 5.92 to 8.81, 45.36 to 79.19, and 7.67 to 8.71, respectively in the wetland that had been restored for 12 yr. These results were similar to those from the natural wetland and the wetland that had been restored for 21 yr(P > 0.05). Soil nutrients changes occurred mainly in the upper layers(≤ 30 cm), and no significant differences were found in deeper soils(> 30 cm). Based on this, we inferred that it would take at least 34 yr for SOC, TN, and TP concentrations and 12 yr for RC N, R CP, and RN P in the top soils of degraded wetlands to recover to levels of natural wetlands. Soil salinity negatively influenced SOC(r =-0.704, P < 0.01), TN(r =-0.722, P < 0.01), and TP(r =-0.882, P < 0.01) concentrations during wetland restoration, which indicates that reducing salinity is beneficial to SOC, TN, and TP recovery. Moreover, plants were an important source of soil nutrients and vegetation restoration was conducive to soil nutrient accumulation. In brief, wetland restoration increased the accumulation of soil biogenic elements, which indicated that positive ecosystem functions changes had occurred. 展开更多
关键词 inland soda saline-alkali wetland wetland degradation and restoration soil nutrients ecological stoichiometry Phragmites australis
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Climate Characteristics of the Formation of Dense Fog during Autumn and Winter in Shandong Inland 被引量:1
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作者 郗兴文 《Meteorological and Environmental Research》 CAS 2010年第4期47-51,共5页
We use historical materials of monthly foggy days from 84 stations of Shandong Province during the latest decades,analyze the spatial distribution features of mean foggy days during autumn and winter and annual mean f... We use historical materials of monthly foggy days from 84 stations of Shandong Province during the latest decades,analyze the spatial distribution features of mean foggy days during autumn and winter and annual mean foggy days in Shandong.Result shows that foggy weather have strong regional characteristics,there are obvious difference between Shandong inland and coast in terms of the frequency of foggy days,winter and autumn are the peak period of dense fog in the inland of Shandong,however,dense fog is less in coastal area.Take Jinan for example,we have emphatically analyzed the activity change rules of foggy days during autumn and winter since 1952 in the inland,as well as the characteristics of atmospheric circulation during the frequently-occurring year and less frequently-occurring year of dense fog. 展开更多
关键词 Dense fog Climate characteristics Shandong inland Autumn and winter China
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Numerical Study on the Leakage and Diffusion Characteristics of Low-Solubility and Low-Volatile Dangerous Chemicals from Ship in Inland Rivers 被引量:3
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作者 Shuifen Zhan Mingchao Wang +4 位作者 Min Wang Qianqian Shao Zefang Zhang Wenxin Jiang Xuemin Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第4期217-235,共19页
Considering the accidents of ships for dangerous chemicals transportation in inland rivers,a numerical method for the simulation of the leakage and diffusion processes of dangerous chemicals in inland rivers is propos... Considering the accidents of ships for dangerous chemicals transportation in inland rivers,a numerical method for the simulation of the leakage and diffusion processes of dangerous chemicals in inland rivers is proposed in this paper.Geographic information,such as rivers and buildings in the model,is obtained through Google Earth and structures of rivers and buildings are described by Auto CAD.In addition,the Fluent is adopted to simulate the leakage and diffusion processes of the dangerous chemicals where the standard k-εmodel is used to calculate the turbulent flow.Considering the interaction between chemicals and water,the VOF method is used to describe the leakage,drift and diffusion process of dangerous chemicals groups on the water surface.Taking a section of the Yangtze River as an example,the leakage and diffusion processes from a ship carrying 3,000 tons of low-solubility and low-volatile dangerous chemicals are studied,and the characteristics of leakage and diffusion are analyzed in detail.During the simulation,the area of the maximum group of leaked dangerous chemicals reaches up to about 1800 m2,and the number reaches up to 45.Furthermore,the influence of density,viscosity,water velocity and leakage velocity on the leakage and diffusion processes is investigated in this paper. 展开更多
关键词 inland rivers low-solubility and low-volatile dangerous chemicals leakage and diffusion VOF.
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The Use of Hydrogen as a Fuel for Inland Waterway Units 被引量:3
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作者 M. Morsy El Gohary Yousri M. A. Welaya AmrAbdelwahabSaad 《Journal of Marine Science and Application》 2014年第2期212-217,共6页
Escalating apprehension about the harmful effects of widespread use of conventional fossil fuels in the marine field and in internal combustion engines in general, has led to a vast amount of efforts and the directing... Escalating apprehension about the harmful effects of widespread use of conventional fossil fuels in the marine field and in internal combustion engines in general, has led to a vast amount of efforts and the directing of large capital investment towards research and development of sustainable alternative energy sources. One of the most promising and abundant of these sources is hydrogen. Firstly, the use of current fossil fuels is. discussed focusing on the emissions and economic sides to emphasize the need for a new, cleaner and renewable fuel with particular reference to hydrogen as a suitable possible alternative. Hydrogen properties, production and storage methods are then reviewed along with its suitability from the economical point of view. Finally, a cost analysis for the use of hydrogen in internal combustion engines is carried out to illustrate the benefits of its use as a replacement for diesel. The outcome of this cost analysis shows that 98% of the capital expenditure is consumed by the equipment, and 68.3% of the total cost of the equipment is spent on the solar photovoltaic cells. The hydrogen plant is classified as a large investment project because of its high initial cost which is about 1 billion US$; but this is justified because hydrogen is produced in a totally green way. When hydrogen is used as a fuel, no harmful emissions are obtained. 展开更多
关键词 sustainable alternative energy sources hydrogen fuel hydrogen properties hydrogen production hydrogen storage costanalysis inland waterway units
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