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71.
Acta Geochimica - In this study, we investigated the chemical composition of dissolved solids in the Ca River basin, North-Central Vietnam. Water samples were collected from August 2017 to July... 相似文献
72.
Shakirov R. B. Cuong Do Huy Obzhirov A. I. Valitov M. G. Lee N. S. Legkodimov A. A. Kalgin V. Yu. Yeskova A. I. Proshkina Z. N. Telegin Yu. A. Storozhenko A. V. Ivanov M. V. Pletnev S. P. Sedin V. T. Bulanov A.V. Shvalov D. A. Lipinskaya N. A. Bovsun M. A. Makseev D. S. Thanh Nguyen Trung Anh Le Duc Luong Le Duc 《Oceanology》2021,61(1):147-149
Oceanology - Abstract—The paper gives brief results of comprehensive studies in the South China Sea obtained from a joint Russian–Vietnamese expedition in November 2019 (cruise 88 of... 相似文献
73.
Le Hung Trinh Zablotskii V. R. Vu Danh Tuyen Zenkov I. V. Tong Thi Hanh 《Izvestiya Atmospheric and Oceanic Physics》2021,57(9):1098-1107
Izvestiya, Atmospheric and Oceanic Physics - In recent years, rapid urbanization and population growth have led to an overload of waste in big cities of Vietnam. Waste decomposition is always... 相似文献
74.
Bayan Alsaaideh Ryutaro Tateishi Dong Xuan Phong Nguyen Thanh Hoan Ahmad Al-Hanbali Bai Xiulian 《地球空间信息科学学报》2017,20(1):29-38
Urban areas are of paramount significance to both the individuals and communities at local and regional scales. However, the rapid growth of urban areas exerts effects on climate, biodiversity, hydrology, and natural ecosystems worldwide. Therefore, regular and up-to-date information related to urban extent is necessary to monitor the impacts of urban areas at local, regional, and potentially global scales. This study presents a new urban map of Eurasia at 500 m resolution using multi-source geospatial data, including Moderate Resolution Imaging Spectroradiometer (MODIS) data of 2013, population density of 2012, the Defense Meteorological Satellite Program’s Operational Linescan System (DMSP-OLS) nighttime lights of 2012, and constructed Impervious Surface Area (ISA) data of 2010. The Eurasian urban map was created using the threshold method for these data, combined with references of fine resolution Landsat and Google Earth imagery. The resultant map was compared with nine global urban maps and was validated using random sampling method. Results of the accuracy assessment showed high overall accuracy of the new urban map of 94%. This urban map is one product of the 20 land cover classes of the next version of Global Land Cover by National Mapping Organizations. 相似文献
75.
Acero Francisco Javier Fernández-Fernández María Isabel Carrasco Víctor Manuel Sánchez Parey Sylvie Hoang Thi Thu Huong Dacunha-Castelle Didier García José Agustín 《Theoretical and Applied Climatology》2018,133(1-2):605-617
Theoretical and Applied Climatology - Heat wave (HW) events are becoming more frequent, and they have important consequences because of the negative effects they can have not only on the human... 相似文献
76.
There is growing recognition of the importance of ecosystem-based approaches for adaptation to climate change—it is a cost-effective measure that has multiple benefits and can overcome many of the drawbacks of more common engineering adaptation options. Viet Nam has a rich biodiversity and is also one of the most vulnerable countries impacted by climate change. Climate change policies have been adopted at national and local levels as well as by sector, making Viet Nam one of the nations to most systematically fulfill their obligation under the United Nations Framework Convention on Climate Change. Consequently, we have used Viet Nam as a case study, to assess the integration of ecosystem-based approach to adaptation to climate change. We found that ecosystem-based adaptation is being implemented in some projects but, overall, is inadequately considered by Viet Nam’s climate change policies. Instead, policies predominantly rename infrastructure projects as climate change adaptation and focus on hard solutions for disaster reduction, rather than responding to long-term climate change through ecosystem-based adaptation. Moreover, ecosystem-based adaptation projects have focused on only a few relevant types of ecosystems. Viet Nam should revise its existing climate change policies and sectoral strategies to integrate ecosystem-based adaptation across different scales of governance. As other nations develop adaptation policies at different scales, the lesson from Viet Nam is that engineering measures need to be balanced with ecosystem-based adaptation for more affordable and effective responses to climate change. 相似文献
77.
Ngo?Thi?LuEmail author M.?V.?Rodkin Tran?Viet?Phuong Nguyen?Quang Phung?Thi?Thu Hang Vu?Thi?Hoan 《Journal of Volcanology and Seismology》2017,11(2):164-171
The highest seismic activity in Vietnam is observed in the northwest of the country, hence the practical significance of more accurate assessment of the earthquake hazard for the area. The worldwide experience of seismicity, in particular, the recent Tohoku mega-earthquake (March 11, 2011, M w = 9.0, Japan) shows that instrumental and historical data alone are insufficient to reliably estimate earthquake hazard. This is all the more relevant in relation to Vietnam where the period of instrumental observation is short and historical evidence is nearly lacking. In this connection we made an attempt to construct maps of earthquake hazard based on known seismicity data using the available geological and geophysical data and the method of G.I. Reisner and his associates for classification of areas by seismic potential. Since the question of what geological and geophysical parameters are to be used and with what weights remains unresolved, we developed a program package to estimate Mmax based on different options in the use of geological and geophysical data. In this paper we discuss the first results and the promise held by this program package. 相似文献
78.
Thi Thuy Van Le Rungruang Lertsirivorakul Tran Vuong Bui Marcia K. Schulmeister 《Ground water》2020,58(6):1012-1022
The coastal aquifers and inland waters of the Long Xuyen Quadrangle and Ca Mau Peninsula of southern Vietnam have been significantly impacted by sea water intrusion (SI) as a result of recent anthropogenic activities. This study identified the evolution and spatial distribution of hydrochemical conditions in coastal aquifers at this region using Hydrochemical Facies Evolution Diagram (HFE-D) and Geographical Information System mapping. Hydraulic heads and water chemistry were measured at 31 observation wells in four layered aquifers during dry and rainy seasons in early (2005), and more recent (2016), stages of agricultural development. Hydrochemical facies associated with intrusion or freshening stages were mapped in each aquifer after assigning mixing index values to each facies. The position of groundwater freshening and SI phases differed in Holocene, Upper Pleistocene, Middle Pleistocene, and Lower Pleistocene aquifers. The geographic position of freshening and intrusion fronts differ in dry and rainy seasons, and shifted after 11 years of groundwater abstraction in all four aquifers. The spatial and temporal differences in hydrochemical facies distributions according to HFE-D reflect the relative impact of SI in the four aquifers. The study results provide a better understanding of the evolution of groundwater quality associated with SI in a peninsular coastal aquifer system, and highlight the need for improving groundwater quality and management in similar coastal regions. 相似文献
79.
The northern coast of Vietnam has accumulated a significant amount of sediment discharged from the multiple distributaries of rivers such as the Red River and Ma River.While recent decreases of the sediment supply appears to have a significant impact on coastal erosion,the complex network of these distributaries makes it difficult to determine the overall spatiotemporal characteristics of sediment discharges and related topographic changes.The goal of the current study is to develop a satellite-based monitoring system for observation of turbidity discharged from the multiple rivers and to investigate the applicability of the developed monitoring system through a case study on the northern coast of Vietnam.Based on the in-situ observed data,a formulawas determined for estimation of the surface water turbidity as a function of the red band reflectance of Moderate Resolution Imaging Spectro-radiometer(MODIS)images.The formula was then combined with a newly determined threshold for cloud-masking to obtain maps of the nearshore turbidity patterns.These maps capture the spatiotemporal water surface turbidity along the entire coast of the Red River Delta and the coast around theMa River mouth over the past sixteen years with frequency of twice a day.Finally,long-term trends of the turbidity patterns from multiple rivers were compared with the in-situ observation data and it was found that the Red River and the Ma River showed clearly contrasting characteristics,which reasonably explain the recent coastal shoreline changes and characteristics of sediment sampled along the coast. 相似文献
80.
Le Duc Luong Shakirov Renat B. Hoang Nguyen Shinjo Ryuichi Obzhirov Anatoly Syrbu Nadezhda Shakirova Maria 《Water Resources》2019,46(5):807-816
Water Resources - This paper presents review of dissolved Rare Earth Elements (REE) and methane anomalies distribution in the East China Sea water column. In general, the REE concentrations of the... 相似文献