Mangrove forest is always considered an effective barrier to protect habitats from high waves,especially tsunami.Therefore,the estimation of wave energy dissipation is required for disater warning.The aim of this stud...Mangrove forest is always considered an effective barrier to protect habitats from high waves,especially tsunami.Therefore,the estimation of wave energy dissipation is required for disater warning.The aim of this study is to calculate wave attenuation in mangrove areas by combining field survey method and mathematical modeling method.The application area is Cu Lao Dung mangrove forest,Soc Trang,Vietnam.From data measurements of hydrodynamics and mangrove characteristics,the wave attenuation coefficient r,the drag coefficient Cd were determined in mud area,mud-mangrove area and mangrove area.In addition,using WAPROMAN model,the attenuation of wave height is simulated in different cases such as without mangrove,with mangrove,breaking wave effect and wave trunk interaction effect.Both the results from the measured method and the model method show the role of mangroves in reducing wave energy.The results from modeling are smaller than the calculated results.However,both methods tend to be suitable.Such difference required more considerations not only on calculation formulas but also on modeling adjustment.The research clearly demonstrated the effectiveness of mangroves in coastal protection,with wave-trunk interaction becoming the dominant factor in energy dissipation deeper into the forest.For future,extending the study to different mangrove forests and longer time scales could provide a more comprehensive understanding of the role of mangroves in coastal protection across various geographical and temporal contexts.展开更多
Nha Trang Bay is famous not only because of its beauty, but also of the biodiversity values, especially coral reefs. Thus, the sea water quality monitoring systems are necessary for effective and available managements...Nha Trang Bay is famous not only because of its beauty, but also of the biodiversity values, especially coral reefs. Thus, the sea water quality monitoring systems are necessary for effective and available managements to protect the ecosystems and for sustainable development. There have been several monitoring systems here but they have been done separately and unconnectedly. This research was done to take an overview and access the status and changes of water quality from 2007-2014. The data obtained rainy seasons over the years showed a quite good environment here. The environment changes were also monitored and there were some changes between seasons and over years, decreasing, increasing, or unobvious trends. However, the difference was not so much; and there was not the sign of environmental degradation in the bay from 2007 to 2014. Besides, the stoichiometric nutrients limitations were initially assessed. Since Si ratios here were always higher compared to N and P, there was not increased potential for non-diatom algal blooms. Together with the recorded nutrients concentration data, it can be said that there was no evidence of eutrophication in the bay. Although there was partial contamination of some parameters at few moments, the sea water quality of Nha Trang bay was still in a good condition （according to Vietnamese and ASEAN criteria）.展开更多
Trang Bang is the largest agricultural production district of TayNinh province, Vietnam that has a great influence on the socio-economic development of the whole province. This study assessed land use - land cover cha...Trang Bang is the largest agricultural production district of TayNinh province, Vietnam that has a great influence on the socio-economic development of the whole province. This study assessed land use - land cover change in Trang Bang district from 1995 to 2017, the results provide scientific evidence for the safe and effective identification of causes and safeguards for mulch. The study was conducted by an expert classification system and the land use/land cover (LULC) was classified into 6 classes: food-crops, fruit-tree, water, built-up, industry and shrub. The result showed that the LULC there decreased between 1995 and 2017. All the two land cover types (food-crops, fruit-tree) decreased 141.2 km2 (41.4%) in 2017 compared with 1995, while the area of industrial and urban land (industry, built-up) increased 70.0 km2 (20.6%). The overall classification accuracies in 1995, 2007, and 2017 were 94.2%, 98.0%, and 96.3% respectively. The overall kappa coefficients for the image classification were 0.90, 0.97, and 0.94 in 1995, 2007, and 2017 respectively. In general, the average classification was above 90%, and this proved that the classification was reliable and acceptable. The result show that the LULC in the study area decreased during 1997-2017 and tended to decrease in recent years.展开更多
Based on the data collected at the Cau Da station, the Regional Ocean Modeling System (ROMS) is applied for hydrodynamics (e.g. circulation and temperature-salinity) in Binh Cang - Nha Trang Bay, Vietnam. The results ...Based on the data collected at the Cau Da station, the Regional Ocean Modeling System (ROMS) is applied for hydrodynamics (e.g. circulation and temperature-salinity) in Binh Cang - Nha Trang Bay, Vietnam. The results present the several cases of hydrodynamic regimes in the Bay during two mainly monsoon seasons (northeast and southwest monsoons). The clearly hydrodynamic regime occurs in the bay due to the impacts of rivers and monsoon conditions. These changes could be contributed to the hydrodynamic systems and water exchanges, that support basic scientific information for sustainable development of Binh Cang - Nha Trang bay.展开更多
This research aimed to examine problems in building up local development plan,construct new meaning scheme of community strategic planning of civil society,and identify strategic guidelines for grassroots economic dev...This research aimed to examine problems in building up local development plan,construct new meaning scheme of community strategic planning of civil society,and identify strategic guidelines for grassroots economic development.Key informants were 145 representatives of civil society from 102 communities in Trang Province,Thailand.Research instruments were dialogue forums which encouraged the key informants to reveal their own experiences in public hearings.Data were analyzed by using interpretation of their own experiences in order to construct new meaning scheme from them.Findings revealed that the problems of previous community strategic plan facilitated by governmental organizations had less concern towards people’s self-reliance and participation to determine their own community future.Civil society participated in construction of new meaning scheme of local development by setting direction concerning existing local assets;e.g.marine resources,mountains,forests and paddy fields.Meanwhile,local people were harmoniously living among diversified cultural and ethnical differences like Buddhists,Muslims,Chinese-Thais,and local ethnic groups.External factors that weakened local capacity are consumerism in today’s society,and governmental mechanism was not conformed to local development.All developmental budgets were arranged by government organizations.Thus,new meaning scheme to development is setting up the directions of local development based on peaceful and strong relationship of community people including reservation of natural and cultural diversity.Furthermore,civil society’s role should be strengthened and reset,while government organizations act as facilitators instead of being commanders.The strategic guidelines included:promoting occupational capacity for small-and medium-sized community enterprises to gain more opportunity in economic space of local wisdom products,conserving the natural resources and bio-diversity,developing physical environment and city plan to support tourism,providing non-formal education to empower intellectual capability of local community leaders,and developing community-based tourism to gain additional income based on the historical and cultural strengths.展开更多
基金funded by Vietnam National University Ho Chi Minh City(VNU-HCM)under grant number B2019-18-09.
文摘Mangrove forest is always considered an effective barrier to protect habitats from high waves,especially tsunami.Therefore,the estimation of wave energy dissipation is required for disater warning.The aim of this study is to calculate wave attenuation in mangrove areas by combining field survey method and mathematical modeling method.The application area is Cu Lao Dung mangrove forest,Soc Trang,Vietnam.From data measurements of hydrodynamics and mangrove characteristics,the wave attenuation coefficient r,the drag coefficient Cd were determined in mud area,mud-mangrove area and mangrove area.In addition,using WAPROMAN model,the attenuation of wave height is simulated in different cases such as without mangrove,with mangrove,breaking wave effect and wave trunk interaction effect.Both the results from the measured method and the model method show the role of mangroves in reducing wave energy.The results from modeling are smaller than the calculated results.However,both methods tend to be suitable.Such difference required more considerations not only on calculation formulas but also on modeling adjustment.The research clearly demonstrated the effectiveness of mangroves in coastal protection,with wave-trunk interaction becoming the dominant factor in energy dissipation deeper into the forest.For future,extending the study to different mangrove forests and longer time scales could provide a more comprehensive understanding of the role of mangroves in coastal protection across various geographical and temporal contexts.
文摘Nha Trang Bay is famous not only because of its beauty, but also of the biodiversity values, especially coral reefs. Thus, the sea water quality monitoring systems are necessary for effective and available managements to protect the ecosystems and for sustainable development. There have been several monitoring systems here but they have been done separately and unconnectedly. This research was done to take an overview and access the status and changes of water quality from 2007-2014. The data obtained rainy seasons over the years showed a quite good environment here. The environment changes were also monitored and there were some changes between seasons and over years, decreasing, increasing, or unobvious trends. However, the difference was not so much; and there was not the sign of environmental degradation in the bay from 2007 to 2014. Besides, the stoichiometric nutrients limitations were initially assessed. Since Si ratios here were always higher compared to N and P, there was not increased potential for non-diatom algal blooms. Together with the recorded nutrients concentration data, it can be said that there was no evidence of eutrophication in the bay. Although there was partial contamination of some parameters at few moments, the sea water quality of Nha Trang bay was still in a good condition （according to Vietnamese and ASEAN criteria）.
文摘Trang Bang is the largest agricultural production district of TayNinh province, Vietnam that has a great influence on the socio-economic development of the whole province. This study assessed land use - land cover change in Trang Bang district from 1995 to 2017, the results provide scientific evidence for the safe and effective identification of causes and safeguards for mulch. The study was conducted by an expert classification system and the land use/land cover (LULC) was classified into 6 classes: food-crops, fruit-tree, water, built-up, industry and shrub. The result showed that the LULC there decreased between 1995 and 2017. All the two land cover types (food-crops, fruit-tree) decreased 141.2 km2 (41.4%) in 2017 compared with 1995, while the area of industrial and urban land (industry, built-up) increased 70.0 km2 (20.6%). The overall classification accuracies in 1995, 2007, and 2017 were 94.2%, 98.0%, and 96.3% respectively. The overall kappa coefficients for the image classification were 0.90, 0.97, and 0.94 in 1995, 2007, and 2017 respectively. In general, the average classification was above 90%, and this proved that the classification was reliable and acceptable. The result show that the LULC in the study area decreased during 1997-2017 and tended to decrease in recent years.
文摘Based on the data collected at the Cau Da station, the Regional Ocean Modeling System (ROMS) is applied for hydrodynamics (e.g. circulation and temperature-salinity) in Binh Cang - Nha Trang Bay, Vietnam. The results present the several cases of hydrodynamic regimes in the Bay during two mainly monsoon seasons (northeast and southwest monsoons). The clearly hydrodynamic regime occurs in the bay due to the impacts of rivers and monsoon conditions. These changes could be contributed to the hydrodynamic systems and water exchanges, that support basic scientific information for sustainable development of Binh Cang - Nha Trang bay.
文摘This research aimed to examine problems in building up local development plan,construct new meaning scheme of community strategic planning of civil society,and identify strategic guidelines for grassroots economic development.Key informants were 145 representatives of civil society from 102 communities in Trang Province,Thailand.Research instruments were dialogue forums which encouraged the key informants to reveal their own experiences in public hearings.Data were analyzed by using interpretation of their own experiences in order to construct new meaning scheme from them.Findings revealed that the problems of previous community strategic plan facilitated by governmental organizations had less concern towards people’s self-reliance and participation to determine their own community future.Civil society participated in construction of new meaning scheme of local development by setting direction concerning existing local assets;e.g.marine resources,mountains,forests and paddy fields.Meanwhile,local people were harmoniously living among diversified cultural and ethnical differences like Buddhists,Muslims,Chinese-Thais,and local ethnic groups.External factors that weakened local capacity are consumerism in today’s society,and governmental mechanism was not conformed to local development.All developmental budgets were arranged by government organizations.Thus,new meaning scheme to development is setting up the directions of local development based on peaceful and strong relationship of community people including reservation of natural and cultural diversity.Furthermore,civil society’s role should be strengthened and reset,while government organizations act as facilitators instead of being commanders.The strategic guidelines included:promoting occupational capacity for small-and medium-sized community enterprises to gain more opportunity in economic space of local wisdom products,conserving the natural resources and bio-diversity,developing physical environment and city plan to support tourism,providing non-formal education to empower intellectual capability of local community leaders,and developing community-based tourism to gain additional income based on the historical and cultural strengths.
