VNU Journal of Science: Earth and Environmental Sciences最新文献

{"title":"Flood Mapping and Impact Assessment in Agricultural Land in Hoa Vang, Da Nang Using Remote Sensing and Google Earth Engine","authors":"Le Ngoc Hanh, Nguyen Hoang Son, Le Phuc Chi Lang, Nguyen Van An, Tran Thi An","doi":"10.25073/2588-1094/vnuees.5068","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.5068","url":null,"abstract":": Hoa Vang district in Da Nang city, is frequently affected by floods. This research was conducted to generate a flood map in Hoa Vang District, Da Nang City, during the peak flooding period in 2022, using Sentinel 1 imagery on the Google Earth Engine (GEE) cloud computing platform. The research also aims to assess the impact of this flooding event on the productivity of agricultural land in the district. Based on the Sentinel 1 imagery's backscattering coefficient, the study utilizes the Otsu algorithm for thresholding to determine the flood inundated areas. The results indicated that the optimal Otsu threshold value range from -16.003 to -10.631 dB. In addition, to assess the reliability of the flood mapping results, the study utilizes the in-situ flood inventory data to calculate the overall error and Kappa index. The research findings indicate a high level of reliability with an overall accuracy of 0.89 and a Kappa index of 0.79. Based on this analysis, the study successfully established a flood map for the peak flooding period 2022 in the study area. Furthermore, the study assessed the impact of floods on agricultural land productivity in the communes of Hoa Vang District. The findings showed that the flooded agricultural land area was 1,979.8 hectares, accounting for 77.3% of the total flooded area and 2.7% of the total natural area, primarily concentrated in the southern communes of the district such as Hoa Tien, Hoa Chau, Hoa Phuoc, and Hoa Phong. These findings serve as scientific background for assessing further impacts of flooding on agricultural land in Hoa Vang District, Da Nang City. \u0000  \u0000  \u0000 ","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"4 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141271977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of PM2.5 in Long Binh Industry Park, Bien Hoa City, Vietnam: Mass Concentrations, Chemical Composition, Source Apportionment, and Health Risk Assessment","authors":"Hoang Anh Le, Bùi Duy Linh, Nguyen Thanh Tuan, Pham Thu Huyen","doi":"10.25073/2588-1094/vnuees.5028","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.5028","url":null,"abstract":"This study aimed to assess the concentration, source, chemical properties, and health risks associated with PM2.5 in Long Binh ward, Bien Hoa city, Dong Nai province, where there is a large distribution of industrial zones. PM2.5 samples were collected using a high-volume sampler during both the dry and rainy seasons. The mass concentration of PM2.5 was determined by Mettler Toledo XS205, and the chemical properties of eleven heavy metal elements were analyzed using inductively coupled plasma mass spectrometry (ICP-MS; iCAP-RQ, Thermo Science, US). The migration trajectory of PM2.5 was determined using the HYSPLIT model. The results showed that the PM2.5 concentration exceeded the WHO recommended value, while only the PM2.5 concentration in the dry season exceeded the national standard gia (QCVN 05:2013/BTNMT). Industry, road and non-road transportation activities were identified as the main sources of PM2.5. The heavy metal element Cr was found to be the most significant contributor to the chemical composition of fine particles. The health risk assessment revealed that the HI values were lower than 1 in both seasons, indicating a low risk of chronic adverse health effects. However, the TRC values  exceeded the recommended threshold for cancer risk in both the rainy season (10-4 ± 6,6 x 10-5) and dry seasons (7,9 x 10-4 ± 5,6 x 10-4).","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"5 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140418322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Removal of DB71 Dye from Water Using Shrimp-shell Chitosan","authors":"Tran Van Son, Nguyen Thanh Ha, Dong Thanh Binh","doi":"10.25073/2588-1094/vnuees.5009","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.5009","url":null,"abstract":"Chitosan is a natural-derived polymer which has been used for water treatment due to its biodegradability. In this study, chitosan adsorbent was successfully fabricated from shrimp crust. The chitosan adsorbents were characterized using FTIR, SEM, and Zeta potential analysis. The experimental results indicated that fabricated chitosan in this study has similar properties to standard chitosan from Sigma-Aldrich which contains functional groups such as -OH, -CH, C-O-C, saccharide rings and amide groups I, II, III. Furthermore, the surface morphology of the adsorbent is moderately flat and the pHPZC was 7.2. Chitosan in flake forms could adsorb DB71 dye in water with a concentration of 35 ppm at the efficiency of 100%. The optimal conditions for the dye removal were at  0.2 g/L of concentration and contact time of 60 minutes. The dye is well adsorbed by chitosan in acidic environment with optimal pH of 3. The main mechanisms of dye adsorption onto the chitosan adsorbent maybe ion exchange or complexation.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":" 27","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139143101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Satellite Images and Artificial Intelligence to Monitor Land Cover Changes in Hanoi Area During 2013-2023 Period","authors":"Dang Thanh Tung, Dinh Thi Thanh Huyen, Hoang Thi Thuy, Ta Minh Ngoc","doi":"10.25073/2588-1094/vnuees.4962","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4962","url":null,"abstract":"Artificial intelligence (AI) and remote sensing technology have now increasingly improved their efficiency and reliability in monitoring the changes in land cover. With the amendment of the Vietnamese Law on Land in 2013 and the administrative boundary expansion of Hanoi, Hanoi experiences significant changes in land use and land cover for the last ten years. To monitor the actual land use changes in the area, this study used the Random Forest (RF) machine learning algorithm to classify the basic land covers, monitor, and analyze the spatial variation of land use and land cover in the 2013 to 2023 period. The study findings indicate a relatively high rate of expansion of construction zone area and a decrease in land cover related to water bodies and vegetated area. Water bodies decrease by an average of 0.8% annually, whereas the construction zone area increased by 7% of the total area.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"4 13","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139147461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Silica-Biochar, Bentonite and Diatomite Ratios on Properties of Controlled Release Fertilizer","authors":"Nguyen Xuan Huan, Nguyen Ngoc Minh, Tran Minh Tien","doi":"10.25073/2588-1094/vnuees.4982","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4982","url":null,"abstract":"Controlled slow release fertilizer (CRF) in this study was produced by mixing Silica-Biochar (SB), Bentonite (B), and Diatomite (D) at different ratios with N, P, K form customized crystal membrane to control the dissolution of N, P, K into water. Research results show that the mixing rate of SB and B significantly affects the pelleting process, decay rate, hardness, and air hygroscopicity of CRF fertilizer. The decay rate is more than 20% after 13 and 5 days and greater than 80% after 17 and 9 days, respectively with SB mixing ratio of 30 and 40%. The maximum hardness of CRF fertilizer was 3.2 kg/cm2 and the smallest was 1.6 kg/cm2 respectively with the SB used ratio of 30 and 40%. With the mixing rate of SB at 30%, the resulting CRF fertilizer has the smallest hygroscopicity. With the mixing rate of B at 5%, the resulting decay rate of CRF was the smallest. The mixing rate of B did not affect the air hygroscopicity of CRF fertilizers. The different mixing rates of diatomite used did not affect the decay rate, hardness, and air hygroscopicity of CRF fertilizers.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":" 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139143121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geological History of Caves and Conservation Values of the World Nature Heritage Phong Nha-Ke Bang National Park","authors":"T. Nghi, Le Nam, Dao Bui Din, D. X. Thanh, Ta Hoa Phuong, Dang Van Bao, Nguyne Thi Huyen Trang","doi":"10.25073/2588-1094/vnuees.4971","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4971","url":null,"abstract":"The long development history and geological diversity of the Phong Nha-Ke Bang area is shown by the rich and diverse lithological composition of the stratigraphic units ranging in age from Devonian to Present day: granite, terrigenous rock, thin-bedded limestone, and massive limestone. The geomorphology of the national park includes limestone mountain terrain alternating with terrigenous rock mountain terrain surrounding the karst valley system. The formation of the cave is an endogenous-exogenous geological process that occurs according to the cycle of global sea level change. The tectonic activity is the mother that gives birth to the caves of different heights and ages. The higher the cave, the older it is, and the oldest cave is 32 million year old-Khe Ry cave. The four fault systems of Northeast - Southwest (NE-SW), Northwest - Southeast (NW-SE), West - East (WE), and North - South (NS) create four cave systems that are deep faults with strong destructive intensity. Exogenous geological activities in the cave have created a uniquely beautiful landscape including three simultaneous processes: i) Chemical washing of driftwood,  mechanical abrasion, polishing of the cave walls, and ceiling caused by travertine floods pouring into it from outside the cave; ii) Precipitation forming stalactites from the ceiling of the cave and precipitation forming stalagmites from the floor of the cave slowly over millions of years; and iii) Travertine sedimentation on the cave floor resulting in many unique sedimentary bodies, specifically filling the rough terrain of limestone blocks, covering the ancient stalactites falling from the cave ceiling, forming spiral mushroom island in the Son Doong cave, and creating gem pebbles located in fan-shaped sunken cells of the cave.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":" 124","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139144737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on Aquaculture Wastewater Treatment by Aquatic Plants","authors":"Nguyen Minh Phuong, Nguyen Huu Hung, Tran Minh Kha, Cung Phuong Hoa","doi":"10.25073/2588-1094/vnuees.4995","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4995","url":null,"abstract":"The aquaculture sector is fast developed in Vietnam, whereas untreated water pollution remains an issue. This study used three aquatic plant species, namely Ceratophyllum demersum, Alternanthera paronychioides, and Cyperus corymbosus to treat aquaculture wastewater in Quang Ninh. In the experiment with shrimp farming wastewater, after 16 days of experiment, the results showed C. demersum had the highest ability to remove organic matter (COD) up to 95.2% and the removal efficiency of NH4+-N reached 96.3%, whereas the removal efficiency of organic matter (COD) and NH4+-N of A. paronychioides were 90.5% and 97%, respectively; the removal efficiency of organic matter (COD) and NH4+-N of C. corymbosus were 66.7% and 81.8%, respectively. In the experiment with fish farming wastewater, C. corymbosus had the highest ability to remove organic matter (COD) up to 96% and the removal efficiency of NH4+-N reached 100%, the removal efficiency of organic matter (COD) and NH4+-N of A. paronychioides were 91.8% and 86%, respectively; the removal efficiency of organic matter (COD) and NH4+-N of C. demersum were 83.7% and 76.4%, respectively; whereas in the control sample, the removal efficiency of organic matter (COD) and NH4+-N were only 34.7% and 56%, respectively. In the experiment with shrimp farming wastewater, NO3--N treatment efficiency in the C. corymbosus, C. demersum and A. paronychioides system was 76.1%, 78.7% and 82%, respectively after 3 days of experiment, however NO3--N concentration gradually increased until the 16th day. In the experiment with fish farming wastewater, NO3--N concentration gradually increased during 16 experimental days in systems using three aquatic plants (NO3--N < 3 mg/L at the end of the experiment). The results prove the ability to treat organic matter and ammonium of C. demersum, A. paronychioides and C. corymbosus, however, further studies need to be conducted to limit the increase of NO3--N concentration in aquaculture wastewater treatment. Keywords: wastewater, aquaculture, aquatic plants.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"93 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139147337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studying effects of emissions from thermal power plants on ambient air quality in Cam Pha city","authors":"Pham Thi Thu Ha, Pham Chi Linh, Do Manh Dung, Duong Ngoc Bach","doi":"10.25073/2588-1094/vnuees.4999","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4999","url":null,"abstract":"The article presents some research results on assessing emissions from the chimneys of Cam Pha, Mong Duong 1 and Mong Duong 2 thermal power plants through comparison of the concentrations of TSP, SO2 and NOx with national and local standards on industrial emissions (QCVN 22:2009/BTNMT, QCDP 5:2020/QN), and applying AERMOD VIEW 10.2.1 software to simulate pollutant dispersions in order to evaluate the effects of this emission on ambient air quality in Cam Pha city. The research results show that at several times, the emission concentrations of all three parameters of TSP, NOx và SO2 were higher than standard values, with the maximum frequencies of exceeding standard were 2,79%, 25,92% and 8%, respectively. The maximum levels of exceeding standard were 4,29 times for TSP, 4,04 times for NOx and 7,17 times for SO2. The research results also indicate that there is a place where the hourly average concentration of NO2 is 2.7 times higher than the local standard QCDP 4:2020/QN on ambient air quality. The simulation results of pollutant dispersions showed that the area in the west-northwest of Mong Duong 1 and 2 thermal power plants has concentrations of SO2 and NO2 (hourly average) exceeding the current allowable standards.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":" 25","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139144117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the Impact of Erosion and Farming Practices on the Spatial Distribution of Topsoil Characteristics in a Sloping Vineyard Using an Open-source QGIS Software","authors":"Pham Thi Ha Nhung, Nguyen Quoc Viet","doi":"10.25073/2588-1094/vnuees.5016","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.5016","url":null,"abstract":"Erosion is one of the major threats that negatively affect agricultural soils. Several studies indicated that sloping vineyards are prone to soil erosion due to the soil management method. This study was conducted in a sloping vineyard planted in 2019 (with a slope of 100 and a slope length of 38 m) in Thu Cuc commune, Tan Son district, Phu Tho province, Vietnam. The main objective of the study is to evaluate soil characteristics (pH, particle-size distribution, organic matter, cation exchange capacity (CEC), N, P, and K macronutrients) related to terrain morphology, soil erosion, and farming practices. The open-source QGIS software was used to evaluate the spatial distribution of the soil characteristics. We found that the organic matter content, CEC, and clay content in the soils taken at the footslope zones were higher than those at the top of the hill as a result of soil erosion. In contrast, higher contents of K and silt were observed at the top of the hill compared to the footslope, indicating an unapparent impact of soil erosion on these two factors in the studied vineyard. Phosphorus was evenly distributed throughout the plot and influenced by the soil characteristics. Indeed, a strong correlation between total P content and soil pH, organic matter, and silt content was revealed in our study. On the other hand, cultivation practices exerted a significant impact on the prevailing accumulation of soil organic matter, CEC, total N, and clay particle size at the lower part of the vine rows following the horizontal flow. The vine rows were planted along the contour lines rather than the dominant slope of the vineyard can explain this tendency. In addition, no cover crops sown between the vine rows probably resulted in intense soil erosion at the steepest part of the terrain. Overall, the terrain morphology and farming practices played an essential role in the spatial distribution of soil characteristics. Therefore, integrating geographic information systems into building a digital database and predicting the spatial distribution of soil parameters is necessary to perform soil quality monitoring and serve sustainable land management.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"99 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139146246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation of Plastic Waste Leakage to Environment in Ha Tinh Province, Vietnam","authors":"Duong Thi Quynh Hoa, Luu Viet Dung, N. T. Tue, T. D. Quy, Pham Van Hieu, M. T. Nhuan","doi":"10.25073/2588-1094/vnuees.4973","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4973","url":null,"abstract":"In recent years, the high demand for plastic products in Vietnam has led to an increase in plastic waste leakage into the environment, causing negative impacts on the environment and the ecosystems. In this study, the plastic leakage to the environment from the domestic solid waste in 13 districts of Ha Tinh province was estimated by a Waste Flow Model from 2018-2021 and forecasting to the 2025-2030 period. Results showed that the total plastic waste generated in Ha Tinh province increased from 20,983 tons/year to 23,483 tons/year during the 2018-2021 period. However, the plastic waste released into the environment and leakage into the aquatic environment decreased from 3,022 tons/year to 2,001 tons/year and from 490 tons/year to 361 tons/year in the same period, respectively. Forecasting for the 2025-2030 period, the high collection rate of domestic waste scenario (95%) resulted in 14,664 tons and 1,496 tons, respectively, of total plastic waste released into the environment and aquatic environment. With the low collection rate of domestic solid waste scenario (90%), the total plastic waste leakage into the environment and aquatic environment were 19,068 tons and 1,788 tons, respectively. This result showed that increasing collection and recycling rates of plastic waste may reduce plastic leakage to the environment. It is necessary to monitor and evaluate the impact of plastic waste leakage on the environment and the ecosystems.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"91 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139147383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}