Ho Chi Minh City(HCMC)has a high density of rivers and canals,so it is often strongly affected by high tides.The rapid urbanization process of a city with more than 13 million people,along with human activities with r...Ho Chi Minh City(HCMC)has a high density of rivers and canals,so it is often strongly affected by high tides.The rapid urbanization process of a city with more than 13 million people,along with human activities with rivers such as accretion,river encroachment,sand mining,construction of houses close to the riverbanks,...that stop the flow of rivers and canals,causes high tides to rise quickly and recede slowly,therefore difficult to control.The residential areas of people along the canals in the city are clearly affected by the phenomenon of high tides and it causes many difficulties to people’s lives,especially people living in Nha Be district-a southeast district of HCMC,where the terrain is low-lying,and also the water collection area of the whole city.This is an area that is expected to be flooded more and more heavily due to the increasingly strong impact of high tides.The inevitable consequence of the flooding-high tide phenomenon is that the living and business environment is not guaranteed,people’s life quality does not improve,and a part of the residents have to relocate.So,how to build a housing model that adapts to flooding/high tide in Nha Be District,HCMC against the impacts of high tides?This article is a qualitative study using mixed methods including Document Synthesis&Comparison,Questionnaire,Interview,and Observation methods.The investigation,survey,and assessment on the impact of high tides on housing in Nha Be District,HCMC was carried out in the year 2019-2020.This study aims to find out the experiences in building models of houses that can adapt to flood/high tide and their applicability to some types of houses in Nha Be District,HCMC.These solutions are aimed at improving the quality of life of people living along the canals of Nha Be District,HCMC and effectively contribute to sustainable socio-economic development.展开更多
Background:Anthropogenic disturbance can negatively affect an animal's energy budget by evoking movement responses.Existing research focuses mainly on immediate displacement as a disturbance effect,since this can ...Background:Anthropogenic disturbance can negatively affect an animal's energy budget by evoking movement responses.Existing research focuses mainly on immediate displacement as a disturbance effect,since this can be easily observed in the field. However, effects on movement over longer timescales are poorly examined and it is largely unknown if and to what extent they reflect immediate responses.Longer-term responses could for example be larger than immediate responses if birds, after disturbance, return to the original location and thereby travel twice the immediate disturbed distance. Methods:We combined GPS tracking data with observational data to quantify the effects of anthropogenic (air force and walkers) and non-anthropogenic disturbances on distances travelled by roosting Eurasian Oystercatchers (Haematopus ostralegus) during the non-breeding season. We compared immediate displacement after a disturbance with distance travelled during the entire high tide period (longer-term response), while accounting for environmental factors.Additionally,we calculated energy expenditure due to disturbance based on observed disturbance frequencies.Results:Disturbance resulted in an immediate displacement response of ~200 m (median).Air force disturbances tended to yield larger immediate responses than walker and,especially,than non-anthropogenic disturbances.Longer-term responses and immediate responses were approximately similar,suggesting that,over longer timescales,spatial disturbance effects in the study area remain confined to immediate effects.However,disturbances were infrequent (0.17 disturbances per bird per hour) and most disturbances were of natural origin (62%).Consequently, anthropogenic disturbance of roosting oystercatchers in the study area on average costs 0.08% of the daily energy expenditure. Conclusions:Our results suggest that immediate spatial responses to disturbance can be a useful proxy for spatial responses over longer timescales.Over the non-exhaustive range of conditions investigated,energetic consequences of spatial disturbance responses for an oystercatcher in the study area are marginal due to low disturbance levels.展开更多
Urban flooding in low-lying coastal regions(LCRs)is intensifying due to climate change and sea-level rise;however,the complex interplay of hydrological,climatic,and anthropogenic drivers remains poorly understood.This...Urban flooding in low-lying coastal regions(LCRs)is intensifying due to climate change and sea-level rise;however,the complex interplay of hydrological,climatic,and anthropogenic drivers remains poorly understood.This study investigates the specific meteo-hydrological factors linking climate-induced changes and human activities to the urban flooding event in My Tho City,a vulnerable coastal city in Vietnam's Tien Giang Province,from February 9 to 12,2024.Analyzing historical meteo-hydrological data(rainfall,monsoon winds,river discharge,and water levels),we examined the contributing factors.Our findings reveal that the flooding was predominantly driven by the combination of high astronomical tidal levels and significant water surges.These surges were amplified by northeast monsoon circulation.This situation was compounded by critically low Mekong River discharge during the dry season,which enhanced the inland penetration of tidal effects.Rainfall during the period was minimal and did not contribute significantly.We utilized a filtering technique to differentiate between astronomical tides and non-tidal surges in the water level data.These results provide empirical evidence demonstrating that climate-driven sea-level influences(manifesting as high tides and surges)and anthropogenic alterations to river flow governed the urban flooding dynamics.The study underscores the urgent need for integrated adaptation solutions addressing the complex land-ocean interactions, particularly in the context ofclimate change and relative sea-level rise.展开更多
The spatial distribution of physico-chemical parameters（sea surface temperature（SST）, p H, sea surface salinity（SSS）, dissolved oxygen（DO） and Secchi depth） along with filterable nutrients（dissolved inorganic...The spatial distribution of physico-chemical parameters（sea surface temperature（SST）, p H, sea surface salinity（SSS）, dissolved oxygen（DO） and Secchi depth） along with filterable nutrients（dissolved inorganic nitrate（DIN）,dissolved inorganic phosphate（DIP） and reactive silicate（DSi）） are measured in the winter months of November,December, January and February for four consecutive years from 2009–2010 to 2012–2013 on the shallow continental shelf（〈20 m bathymetry） of the coastal waters（up to 18 km away from shoreline） of the northern Bay of Bengal（n Bo B） during the highest high tide（HHT） and lowest low tide（LLT） hours for the first time. The variability of the coastal biogeochemical environment is assessed during the HHT and LLT hours and for this purpose, seawater samples are collected from seven different locations of a transect in the coastal region. Physicochemical parameters（except SST） show significant difference in magnitude during the HHT and LLT hours respectively. p H, SSS and DO are found to increase in the HHT hours and vice-versa. The data reveal that during the LLT hours, a relative increase of freshwater input in the n Bo B can have elevated the nutrient concentration compared with that observed during the HHT hours. The ratio of nutrient concentration is found to deviate significantly from the Redfield ratio. The abundance of DIP is much higher compared with that of DIN and DSi.The anthropogenic sources of DIP from the upstream flow（especially the domestic effluent of several metropolises） can be mainly attributed behind such an observation. In order to characterize and establish the trend of such variation in such an important bio-climatic region, long-term and systematic ecosystem monitoring in the coastal water of the n Bo B northern Bay of Bengal should be carried out throughout the year.展开更多
Borehole inclinometers are important observation instruments used to measure ground tilt movement and monitor crustal deformation of solid tides and geological landslide disasters.They are widely used in oil explorati...Borehole inclinometers are important observation instruments used to measure ground tilt movement and monitor crustal deformation of solid tides and geological landslide disasters.They are widely used in oil exploration,mineral resource drilling,well logging,exploration and other fields.There is potential for development of rock stress strain monitoring tools.Many types of tiltmeters have been installed,such as SQ-7,FSQ,VS and JB.However,these tiltmeters are generally installed in a deep cave to avoid the interference of temperature,humidity,and human activities.With the urbanization of human society,suitable installation locations are difficult to find.To solve the problem,a two-component borehole tiltmeter,named the CBT-type tiltmeter,is proposed in this paper.It can be installed in a borehole less than500 m deep to eliminate environmental influences.The tiltmeter is composed of two sophisticated gravitational swing and two capacitive transducers.From preliminary theory and experiment analysis,its linear correlation coefficient is higher than 0.99,its co-seismic response is rapid and its noise level is up to 10 4arc seconds in practice.展开更多
Based on the theory of oxidative stress, it is believed that the induction of antioxidant components of the cellular defense system reflects the adaptive compensatory response of an organism aimed at overcoming stress...Based on the theory of oxidative stress, it is believed that the induction of antioxidant components of the cellular defense system reflects the adaptive compensatory response of an organism aimed at overcoming stressful conditions. Therefore, this work concentrated on investigating the effect of the low and high tides on the antioxidant system of L. （Littorina） kurila and also compared the antioxidant parameters of two species of gastropods： intertidal--L, kurila and subtidal--L, squalida. The following parameters were evaluated in the hepatopancreas of mollusks： the activity of the antioxidant enzymes SOD （superoxide dismutase）, CAT （catalase）, and GR （glutathione reductase）, the production of ROS （reactive oxygen species）, and the levels of GSH （glutathione） and the lipid peroxidation product-MDA （malondialdehyde）. The results of this work indicate that the state of the antioxidant system of L. kurila reflected the adaptive capacity of the species in the changing environmental conditions.展开更多
THE founding of New China in 1949 put an end to a half century of strife and war in China. Encouraged by the government of New China and because of the state’s need to resume production and develop the economy, Chine...THE founding of New China in 1949 put an end to a half century of strife and war in China. Encouraged by the government of New China and because of the state’s need to resume production and develop the economy, Chinese women, who for thousands of years had been enclosed within the walls of their home, obtained the right and the chance for extensive employment for the first time. They took a historical step out of their homes. At the First Plenary Session of the Chinese People’s Political Consultative Conference (CPPCC) which was held just before the founding of New China, the "CPPCC Common Program"展开更多
基金Le-Minh Ngo,which was made possible by a 2018-2020 Ho Chi Minh City Department of Science and Technology Grant.Among the contributions,space design solutions were designed and illustrated by the master’s students of architecture,under the supervision of Le-Minh Ngo,in 2019-2020.
文摘Ho Chi Minh City(HCMC)has a high density of rivers and canals,so it is often strongly affected by high tides.The rapid urbanization process of a city with more than 13 million people,along with human activities with rivers such as accretion,river encroachment,sand mining,construction of houses close to the riverbanks,...that stop the flow of rivers and canals,causes high tides to rise quickly and recede slowly,therefore difficult to control.The residential areas of people along the canals in the city are clearly affected by the phenomenon of high tides and it causes many difficulties to people’s lives,especially people living in Nha Be district-a southeast district of HCMC,where the terrain is low-lying,and also the water collection area of the whole city.This is an area that is expected to be flooded more and more heavily due to the increasingly strong impact of high tides.The inevitable consequence of the flooding-high tide phenomenon is that the living and business environment is not guaranteed,people’s life quality does not improve,and a part of the residents have to relocate.So,how to build a housing model that adapts to flooding/high tide in Nha Be District,HCMC against the impacts of high tides?This article is a qualitative study using mixed methods including Document Synthesis&Comparison,Questionnaire,Interview,and Observation methods.The investigation,survey,and assessment on the impact of high tides on housing in Nha Be District,HCMC was carried out in the year 2019-2020.This study aims to find out the experiences in building models of houses that can adapt to flood/high tide and their applicability to some types of houses in Nha Be District,HCMC.These solutions are aimed at improving the quality of life of people living along the canals of Nha Be District,HCMC and effectively contribute to sustainable socio-economic development.
基金provided by the Applied and Engineering Sciences domain of the Netherlands Organisation for Scientific Research(NWO-TTW 14638)by the Royal Netherlands Air Force,Birdlife Netherlands,NAM gas exploration,and Deltares
文摘Background:Anthropogenic disturbance can negatively affect an animal's energy budget by evoking movement responses.Existing research focuses mainly on immediate displacement as a disturbance effect,since this can be easily observed in the field. However, effects on movement over longer timescales are poorly examined and it is largely unknown if and to what extent they reflect immediate responses.Longer-term responses could for example be larger than immediate responses if birds, after disturbance, return to the original location and thereby travel twice the immediate disturbed distance. Methods:We combined GPS tracking data with observational data to quantify the effects of anthropogenic (air force and walkers) and non-anthropogenic disturbances on distances travelled by roosting Eurasian Oystercatchers (Haematopus ostralegus) during the non-breeding season. We compared immediate displacement after a disturbance with distance travelled during the entire high tide period (longer-term response), while accounting for environmental factors.Additionally,we calculated energy expenditure due to disturbance based on observed disturbance frequencies.Results:Disturbance resulted in an immediate displacement response of ~200 m (median).Air force disturbances tended to yield larger immediate responses than walker and,especially,than non-anthropogenic disturbances.Longer-term responses and immediate responses were approximately similar,suggesting that,over longer timescales,spatial disturbance effects in the study area remain confined to immediate effects.However,disturbances were infrequent (0.17 disturbances per bird per hour) and most disturbances were of natural origin (62%).Consequently, anthropogenic disturbance of roosting oystercatchers in the study area on average costs 0.08% of the daily energy expenditure. Conclusions:Our results suggest that immediate spatial responses to disturbance can be a useful proxy for spatial responses over longer timescales.Over the non-exhaustive range of conditions investigated,energetic consequences of spatial disturbance responses for an oystercatcher in the study area are marginal due to low disturbance levels.
基金supported by the Vietnam National University,Ho Chi Minh City(VNU-HCM)project entitled“Identifying and quantifying drivers causing water level fluctuations in the Vietnamese Mekong Delta”grant number[B2024-18-01].
文摘Urban flooding in low-lying coastal regions(LCRs)is intensifying due to climate change and sea-level rise;however,the complex interplay of hydrological,climatic,and anthropogenic drivers remains poorly understood.This study investigates the specific meteo-hydrological factors linking climate-induced changes and human activities to the urban flooding event in My Tho City,a vulnerable coastal city in Vietnam's Tien Giang Province,from February 9 to 12,2024.Analyzing historical meteo-hydrological data(rainfall,monsoon winds,river discharge,and water levels),we examined the contributing factors.Our findings reveal that the flooding was predominantly driven by the combination of high astronomical tidal levels and significant water surges.These surges were amplified by northeast monsoon circulation.This situation was compounded by critically low Mekong River discharge during the dry season,which enhanced the inland penetration of tidal effects.Rainfall during the period was minimal and did not contribute significantly.We utilized a filtering technique to differentiate between astronomical tides and non-tidal surges in the water level data.These results provide empirical evidence demonstrating that climate-driven sea-level influences(manifesting as high tides and surges)and anthropogenic alterations to river flow governed the urban flooding dynamics.The study underscores the urgent need for integrated adaptation solutions addressing the complex land-ocean interactions, particularly in the context ofclimate change and relative sea-level rise.
基金Indian National Centre for Ocean Information Services(INCOIS)of the Ministry of Earth Science of Indiathe INSPIRE fellowship of Department of Science and Technology of India
文摘The spatial distribution of physico-chemical parameters（sea surface temperature（SST）, p H, sea surface salinity（SSS）, dissolved oxygen（DO） and Secchi depth） along with filterable nutrients（dissolved inorganic nitrate（DIN）,dissolved inorganic phosphate（DIP） and reactive silicate（DSi）） are measured in the winter months of November,December, January and February for four consecutive years from 2009–2010 to 2012–2013 on the shallow continental shelf（〈20 m bathymetry） of the coastal waters（up to 18 km away from shoreline） of the northern Bay of Bengal（n Bo B） during the highest high tide（HHT） and lowest low tide（LLT） hours for the first time. The variability of the coastal biogeochemical environment is assessed during the HHT and LLT hours and for this purpose, seawater samples are collected from seven different locations of a transect in the coastal region. Physicochemical parameters（except SST） show significant difference in magnitude during the HHT and LLT hours respectively. p H, SSS and DO are found to increase in the HHT hours and vice-versa. The data reveal that during the LLT hours, a relative increase of freshwater input in the n Bo B can have elevated the nutrient concentration compared with that observed during the HHT hours. The ratio of nutrient concentration is found to deviate significantly from the Redfield ratio. The abundance of DIP is much higher compared with that of DIN and DSi.The anthropogenic sources of DIP from the upstream flow（especially the domestic effluent of several metropolises） can be mainly attributed behind such an observation. In order to characterize and establish the trend of such variation in such an important bio-climatic region, long-term and systematic ecosystem monitoring in the coastal water of the n Bo B northern Bay of Bengal should be carried out throughout the year.
基金the research grant from Institute of Crustal Dynamics,CEA (No.ZDJ2013-07)Key Project of the National Twelfth-Five Year Research Program of China (No.2012BAK19B)
文摘Borehole inclinometers are important observation instruments used to measure ground tilt movement and monitor crustal deformation of solid tides and geological landslide disasters.They are widely used in oil exploration,mineral resource drilling,well logging,exploration and other fields.There is potential for development of rock stress strain monitoring tools.Many types of tiltmeters have been installed,such as SQ-7,FSQ,VS and JB.However,these tiltmeters are generally installed in a deep cave to avoid the interference of temperature,humidity,and human activities.With the urbanization of human society,suitable installation locations are difficult to find.To solve the problem,a two-component borehole tiltmeter,named the CBT-type tiltmeter,is proposed in this paper.It can be installed in a borehole less than500 m deep to eliminate environmental influences.The tiltmeter is composed of two sophisticated gravitational swing and two capacitive transducers.From preliminary theory and experiment analysis,its linear correlation coefficient is higher than 0.99,its co-seismic response is rapid and its noise level is up to 10 4arc seconds in practice.
文摘Based on the theory of oxidative stress, it is believed that the induction of antioxidant components of the cellular defense system reflects the adaptive compensatory response of an organism aimed at overcoming stressful conditions. Therefore, this work concentrated on investigating the effect of the low and high tides on the antioxidant system of L. （Littorina） kurila and also compared the antioxidant parameters of two species of gastropods： intertidal--L, kurila and subtidal--L, squalida. The following parameters were evaluated in the hepatopancreas of mollusks： the activity of the antioxidant enzymes SOD （superoxide dismutase）, CAT （catalase）, and GR （glutathione reductase）, the production of ROS （reactive oxygen species）, and the levels of GSH （glutathione） and the lipid peroxidation product-MDA （malondialdehyde）. The results of this work indicate that the state of the antioxidant system of L. kurila reflected the adaptive capacity of the species in the changing environmental conditions.
文摘THE founding of New China in 1949 put an end to a half century of strife and war in China. Encouraged by the government of New China and because of the state’s need to resume production and develop the economy, Chinese women, who for thousands of years had been enclosed within the walls of their home, obtained the right and the chance for extensive employment for the first time. They took a historical step out of their homes. At the First Plenary Session of the Chinese People’s Political Consultative Conference (CPPCC) which was held just before the founding of New China, the "CPPCC Common Program"
