scholarly journals Analysis of the changes and driving force of the water area in the Ulungur Lake over the past 40 years

2020 ◽  
Vol 69 (5) ◽  
pp. 500-511
Author(s):  
Fan Gao ◽  
Bing He ◽  
Zhenglon Yan ◽  
Songsong Xue ◽  
Yizhen Li
Keyword(s):  
Lake Water ◽  
Human Activities ◽  
Image Data ◽  
Water Area ◽  
Climate Trends ◽  
Humid Climate ◽  
Index Method ◽  
Water Index ◽  
The Past ◽  
Terminal Lakes

Abstract The inland lakes in arid regions, especially the terminal lakes, are highly sensitive to the influence of human activities and climate change. In order to analyze the evolution of the area of water in Ulungur Lake (Buluntuohai Lake, Jili Lake) and the main causes of those changes, 3S technology, satellite data preprocessing, water extraction and database construction methods are combined with consideration of climatic changes and human activity in this study. The data in this study include 11 phases of remote sensing image data, field mapping data and relevant attribute data of the study area from 1977 to 2017. The results demonstrated the following. (1) Over the past 40 years, the change in Ulungur Lake's area was characterized by natural expansion, fluctuation stability, and recovery increase. Significant changes were mainly concentrated in the waters of Zhonghaizi, Xiaohaizi, Camel's Neck, and the waters near Akekule. (2) The period from 1977 to 1995 was the expansion period of the lake water area, and human activities were the main driving factors. The period from 2000–2017 was a smaller period of expansion of the lake water area, with warmer and more humid climate trends combined with human activities driving the change. (3) The water area that was extracted based on the MNDWI water index method can increase the contrast between bodies of water and buildings, which can aid in interpreting and extracting water element information from flat terrain and single types of surface features. This can provide an effective technical means for quantitative and dynamic analysis of the temporal and spatial changes in lake water area.

scholarly journals OBSERVING THE INUNDATED AREA USING LANDSAT-8 MULTITEMPORAL IMAGES AND DETERMINATION OF FLOOD-PRONE AREA IN BANDUNG BASIN

2019 ◽  
Vol 15 (2) ◽  
pp. 131
Author(s):  
Fajar Yulianto ◽  
NFn Suwarsono ◽  
Sayidah Sulma ◽  
Muhammad Rokhis Khomarudin
Keyword(s):  
Land Surface ◽  
Land Use Changes ◽  
Image Data ◽  
Landsat 8 ◽  
Flood Events ◽  
Water Index ◽  
The Past ◽  
Prone Area ◽  
Flood Prone Area ◽  
Flood Prone Areas

Flood is the most frequent hydro-meteorological disaster in Indonesia. Flood disasters in the Bandung basin result from increasing population density, especially in the Citarum riverbank area, accompanied by land use changes in upstream of the Citarum catchment area which has disrupted the river’s function. One of the basic issues that need to be investigated is which areas of the Bandung basin are prone to flooding. This study offers an effective and efficient method of mapping flood-prone areas based on flood events that have occurred in the past through the use of historical remote sensing image data. In this research, Landsat-8 imagery was used to observe the inundated area in the Bandung basin in the past (2014–2018) using an improved algorithm, the modified normalized water index (MNDWI). The results of the study show that MNDWI is the appropriate parameter to be used to detect flooded areas in the Bandung basin area that have heterogeneous land surface conditions. The flood-prone area was determined based on flood events for 2014 to 2018, identified as inundated areas in the images. The estimation of the flood-prone area in the Bandung basin is 11,886.87 ha. Most of the flood-prone areas are in the subdistricts of Rancaekek, Bojongsoang, Solokan Jeruk, Ciparay, Cileunyi, Bale Endah and Cikancung. This area geographically or naturally is a water habitat area. Therefore, if the area will be used for residential, this will have consequences that flood will always be a threat to the area. 

Spatiotemporal Changes of Riverbed and Surrounding Environment in Yongding River (Beijing section) in the Past 40 Years

2020 ◽  
Vol 64 (4) ◽  
pp. 40407-1-40407-13 ◽  
Author(s):  
Ran Pang ◽  
He Huang ◽  
Tri Dev Acharya
Keyword(s):  
Economic Development ◽  
Water Conservation ◽  
Human Activities ◽  
Urban Areas ◽  
Water Volume ◽  
Cropland Area ◽  
The Past ◽  
Surrounding Environment ◽  
Spatiotemporal Changes ◽  
Yongding River

Abstract Yongding River is one of the five major river systems in Beijing. It is located to the west of Beijing. It has influenced culture along its basin. The river supports both rural and urban areas. Furthermore, it influences economic development, water conservation, and the natural environment. However, during the past few decades, due to the combined effect of increasing population and economic activities, a series of changes have led to problems such as the reduction in water volume and the exposure of the riverbed. In this study, remote sensing images were used to derive land cover maps and compare spatiotemporal changes during the past 40 years. As a result, the following data were found: forest changed least; cropland area increased to a large extent; bareland area was reduced by a maximum of 63%; surface water area in the study area was lower from 1989 to 1999 because of the excessive use of water in human activities, but it increased by 92% from 2010 to 2018 as awareness about protecting the environment arose; there was a small increase in the built-up area, but this was more planned. These results reveal that water conservancy construction, agroforestry activities, and increasing urbanization have a great impact on the surrounding environment of the Yongding River (Beijing section). This study discusses in detail how the current situation can be attributed to of human activities, policies, economic development, and ecological conservation Furthermore, it suggests improvement by strengthening the governance of the riverbed and the riverside. These results and discussion can be a reference and provide decision support for the management of southwest Beijing or similar river basins in peri-urban areas.

The Future of the Planetary Trust in a Kaleidoscopic World

2021 ◽  
pp. 1-8
Author(s):  
Edith Brown Weiss
Keyword(s):  
Artificial Intelligence ◽  
Natural Resource ◽  
Human Activities ◽  
New Technologies ◽  
Future Generations ◽  
Nuclear War ◽  
Human Environment ◽  
The Past ◽  
Resource Degradation ◽  
Shared Goal

Today, it is evident that we are part of a planetary trust. Conserving our planet represents a public good, global as well as local. The threats to future generations resulting from human activities make applying the normative framework of a planetary trust even more urgent than in the past decades. Initially, the planetary trust focused primarily on threats to the natural system of our human environment such as pollution and natural resource degradation, and on threats to cultural heritage. Now, we face a higher threat of nuclear war, cyber wars, and threats from gene drivers that can cause inheritable changes to genes, potential threats from other new technologies such as artificial intelligence, and possible pandemics. In this context, it is proposed that in the kaleidoscopic world, we must engage all the actors to cooperate with the shared goal of caring for and maintaining planet Earth in trust for present and future generations.

scholarly journals Ensemble models on palaeoclimate to predict India's groundwater challenge

2013 ◽  
Vol 2 (3) ◽  
Author(s):  
Partha Sarathi Datta
Keyword(s):  
Climate Change ◽  
Climate Models ◽  
Global Climate ◽  
Global Climate Models ◽  
Humid Climate ◽  
Ensemble Models ◽  
North West ◽  
The Past ◽  
The North ◽  
14C Age

In many parts of the world, freshwater crisis is largely due to increasing water consumption and pollution by rapidly growing population and aspirations for economic development, but, ascribed usually to the climate. However, limited understanding and knowledge gaps in the factors controlling climate and uncertainties in the climate models are unable to assess the probable impacts on water availability in tropical regions. In this context, review of ensemble models on δ18O and δD in rainfall and groundwater, 3H- and 14C- ages of groundwater and 14C- age of lakes sediments helped to reconstruct palaeoclimate and long-term recharge in the North-west India; and predict future groundwater challenge. The annual mean temperature trend indicates both warming/cooling in different parts of India in the past and during 1901–2010. Neither the GCMs (Global Climate Models) nor the observational record indicates any significant change/increase in temperature and rainfall over the last century, and climate change during the last 1200 yrs BP. In much of the North-West region, deep groundwater renewal occurred from past humid climate, and shallow groundwater renewal from limited modern recharge over the past decades. To make water management to be more responsive to climate change, the gaps in the science of climate change need to be bridged.

scholarly journals First in situ record of decadal glacier mass balance (2003–2014) from the Bhutan Himalaya

2016 ◽  
Vol 57 (71) ◽  
pp. 289-294 ◽  
Author(s):  
Phuntsho Tshering ◽  
Koji Fujita
Keyword(s):  
Mass Balance ◽  
Direct Method ◽  
Eastern Himalaya ◽  
Glacier Mass Balance ◽  
Differential Gps ◽  
Humid Climate ◽  
Equilibrium Line Altitude ◽  
The Past ◽  
Southeastern Tibet

AbstractThis study presents the first decadal mass-balance record of a small debris-free glacier in the Bhutan Himalaya, where few in situ measurements have been reported to date. Since 2003 we have measured the mass balance of Gangju La glacier, which covers an area of 0.3km2 and extends from 4900 to 5200ma.s.l., using both differential GPS surveys (geodetic method) and stake measurements (direct method). The observed mass balance ranged from –1.12 to –2.04mw.e. a–1 between 2003 and 2014. The glacier exhibited much greater mass loss than neighbouring glaciers in the eastern Himalaya and southeastern Tibet, which are expected to be sensitive to climate change due to the monsooninfluenced humid climate. Observed mass-balance profiles suggest that the equilibrium-line altitude has been higher than Gangju La glacier since 2003, implying that the entire glacier has experienced net ablation for at least the past decade.

scholarly journals GROUNDWATER VULNERABILITY ASSESSMENT OF SYLHET SADAR USING GIS

2020 ◽  
Vol 32 (2) ◽  
Author(s):  
Md. Ashikur Rahman ◽  
Md. Jahir Alam
Keyword(s):  
Water Depth ◽  
Vulnerability Assessment ◽  
Sustainable Use ◽  
Groundwater Vulnerability ◽  
Hazard Map ◽  
Index Method ◽  
Management Planning ◽  
Water Index ◽  
Index Approach ◽  
Groundwater Vulnerability Assessment

Groundwater has been treated as a vital water supply because of its comparatively low vulnerability to pollution compared to surface water. Due to the health and economic impacts of groundwater contamination, steps to measure groundwater vulnerability are necessary for sustainable groundwater protection and management planning. In this study, an attempt has been made to assess groundwater vulnerability using the overlay index method and to prepare a groundwater vulnerability map using Geographic Information System (GIS) of Sylhet Sadar, a northeastern region of Bangladesh. Also, for the water depth-wise vulnerability assessment, the Water index was generated to observe the effect on chemical concentration for the depth of water. By assigning weight to each pollutant map in the overlay index approach, a combined hazard map was successfully created. The combined hazard map shows a total of 16.04%, 41.36%, and 42.59% of the studied area located in a less, moderate, and severely vulnerable zone, respectively. The combined effect of the chemical concentrations of water gradually decreases with the increase in water depth. Therefore, the developed map can be used as a tool for the management to take initiatives for sustainable use of groundwater.

Effects of human activities and climate change on the reduction of visibility in Beijing over the past 36 years

2018 ◽  
Vol 116 ◽  
pp. 92-100 ◽  
Author(s):  
Xuwu Chen ◽  
Xiaodong Li ◽  
Xingzhong Yuan ◽  
Guangming Zeng ◽  
Jie Liang ◽  
...  
Keyword(s):  
Climate Change ◽  
Human Activities ◽  
The Past

Between Tradition and Innovation in ICT and Teaching

2008 ◽  
pp. 456-463
Author(s):  
Antonio Cartelli
Keyword(s):  
Human Activities ◽  
Knowledge Society ◽  
Transformation Process ◽  
Industrial Society ◽  
The Internet ◽  
The Past

During the past few decades, the expanded use of PCs and the Internet introduced many changes in human activities and cooperated in the transformation process leading from the industrial society to the knowledge society.

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