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Seasonally Dependent Daytime and Nighttime Formation of Oxalic Acid Vapor and Particulate Oxalate in Tropical Coastal and Marine Atmospheres
Le Yan,
Yating Gao,
Dihui Chen,
Lei Sun,
Yang Gao,
Huiwang Gao,
Xiaohong Yao
Oxalic acid is the most abundant low-molecular-weight dicarboxylic acid in theatmosphere and plays a crucial role in the formation of new particles and cloud condensation nuclei. However, most observational studies have focused on particulate oxalate, leaving a significant knowledge gap on oxalic acid vapor. This study investigated the concentrations and formation of oxalic acid vapor and oxalate in PM2.5 at a rural tropical coastal island site in south China across different seasons, based on semi-continuous measurements using an Ambient Ion Monitor-Ion Chromatograph (AIM-IC) system. We replaced the default 25 μL sampling loop on the AIM-IC with a 250 μL loop, improving the ability to distinguish the signal of oxalic acid vapor from noise. The data revealed clear seasonal patterns in the depedent daytime and nighttime formation of oxalic acid vapor, benefiting from high signal-to-noise ratios. Specifically, concentrations were 0.059 ± 0.15 μg m-3 in February and April 2023, exhibiting consistent diurnal variations similar to those of O3, likely driven by photochemical reactions. These values decreased to 0.021 ± 0.07 μg m-3 in November and December 2023, with higher nighttime concentrations likely related to dark chemistry processes, amplified by accumulation due to low mixing layer height. The concentrations of oxalate in PM2.5 were comparable to those of oxalic acid vapor, but exhibited (3-7)-day variations, superimposed on diurnal fluctuations to varying degrees. Additionally, thermodynamic equilibrium calculations were performed on the coastal data, and independent size distributions of particulate oxalate in the upwind marine atmosphere were analyzed to support the findings.
Oxalic acid is the most abundant low-molecular-weight dicarboxylic acid in theatmosphere and plays a crucial role in the formation of new particles and cloud condensation nuclei. However, most observational studies have focused on particulate oxalate, leaving a significant knowledge gap on oxalic acid vapor. This study investigated the concentrations and formation of oxalic acid vapor and oxalate in PM2.5 at a rural tropical coastal island site in south China across different seasons, based on semi-continuous measurements using an Ambient Ion Monitor-Ion Chromatograph (AIM-IC) system. We replaced the default 25 μL sampling loop on the AIM-IC with a 250 μL loop, improving the ability to distinguish the signal of oxalic acid vapor from noise. The data revealed clear seasonal patterns in the depedent daytime and nighttime formation of oxalic acid vapor, benefiting from high signal-to-noise ratios. Specifically, concentrations were 0.059 ± 0.15 μg m-3 in February and April 2023, exhibiting consistent diurnal variations similar to those of O3, likely driven by photochemical reactions. These values decreased to 0.021 ± 0.07 μg m-3 in November and December 2023, with higher nighttime concentrations likely related to dark chemistry processes, amplified by accumulation due to low mixing layer height. The concentrations of oxalate in PM2.5 were comparable to those of oxalic acid vapor, but exhibited (3-7)-day variations, superimposed on diurnal fluctuations to varying degrees. Additionally, thermodynamic equilibrium calculations were performed on the coastal data, and independent size distributions of particulate oxalate in the upwind marine atmosphere were analyzed to support the findings.
Posted: 06 December 2024
Susceptibility and Remanent Magnetization Estimates from Orientation Tools in Borehole Imaging Logs
Julio Cesar S. O. Lyrio,
Ana Patricia Laier,
Jorge Campos Junior,
Ana Natalia Rodrigues,
Luciano Santos Martins
Posted: 06 December 2024
Economic Sustainability Assessment of Paulownia Farms in Dual Production System – Case Studies in Temperate Climates
Cornel Negrușier,
Livia Ramona Buzan,
Ioan Păcurar,
Steluța Maria Sîngeorzan,
Vasile Ceuca,
Alexandru Colișar,
Ileana Andreica,
Sándor Rózsa,
Orsolya Borsai
Posted: 06 December 2024
Research Trend Analysis in the Field of Self-Driving Lab Using Network Analysis and Topic Modeling
Woojun Jung,
Insung Hwang,
Keuntae Cho
Posted: 06 December 2024
Design and Development of an Advanced Sensor Prototype for the Detection of Microplastics
Maximiliano Campos-López,
Ricardo Aguilar-Garay,
Dafne E. Gonzalez-Rodriguez,
Verónica Itzel Mejía-López,
Margoth Marissa Gamboa-Lugo,
Vicente Garibay-Febles,
Marco Antonio Reyes-Guzmán,
Alvaro Gordillo-Sol,
Jorge Alberto Mendoza-Perez
Posted: 06 December 2024
Role of Organic and Chemical Fertilizer in the Co-Migration of Nutrient in Different Types of Ditches on Red Soil Slope Orchard
Wenbin Li,
Chongjun Tang,
Jie Zhang,
Jinjin Zhu,
Xiaoan Chen,
You Hu
The planting of fruit trees on sloping land can bring significant benefits to the local economy, but it also causes different degrees of soil and water erosion problem. In this study, we studied the difference of nutrient migration in the slope ditch runoff. In the 39 scouring tests, grass ditch could reduce the loss of carbon(C), nitrogen(N) and phosphorus(P) by intercepting runoff. There was a positive correlation between runoff and the loss rate of N and P. Flow affected the retention time of runoff in the ditch, and then changed dissolved organic carbon (DOC) loss rate in runoff. The concentration of N and P wouldn't affect N and P loss rate, but would affect N and P total loss amount and DOC loss rate in runoff. The addition of organic fertilizer would significantly increase the N loss rate in runoff, and the change rule of P and DOC loss rate was similar, the co-migration may occurs. To sum up, the importance of the four factors on the migration and loss of C, N and P in ditch runoff was as follows: organic fertilizer (100%) > fertilizer concentration (74.8%) > ditch type (12.6%) > initial flow (10%).
The planting of fruit trees on sloping land can bring significant benefits to the local economy, but it also causes different degrees of soil and water erosion problem. In this study, we studied the difference of nutrient migration in the slope ditch runoff. In the 39 scouring tests, grass ditch could reduce the loss of carbon(C), nitrogen(N) and phosphorus(P) by intercepting runoff. There was a positive correlation between runoff and the loss rate of N and P. Flow affected the retention time of runoff in the ditch, and then changed dissolved organic carbon (DOC) loss rate in runoff. The concentration of N and P wouldn't affect N and P loss rate, but would affect N and P total loss amount and DOC loss rate in runoff. The addition of organic fertilizer would significantly increase the N loss rate in runoff, and the change rule of P and DOC loss rate was similar, the co-migration may occurs. To sum up, the importance of the four factors on the migration and loss of C, N and P in ditch runoff was as follows: organic fertilizer (100%) > fertilizer concentration (74.8%) > ditch type (12.6%) > initial flow (10%).
Posted: 05 December 2024
The Effects Mechanisms of Polymeric Materials Combined with Nitrogen Fertilizer on Soil Biome Features and Microbial Community Metabolism of Drip-Irrigated Wheat in Arid Areas
Yan Sun,
Chunying Wei,
Shenglin Zhang,
Changlong Shao,
Hua Fan,
Dashuang Hong,
Hong Huang,
Kaiyong Wang
Posted: 05 December 2024
Quantifying Emissions and Removals in Malawi’s Forestry Sector: Activity Data and Emission Factor Analysis
Meyru Bhanti,
Rajesh Bista,
Mike Chirwa,
Maggie Munthali,
Austin Tibu,
Mary Chisale,
Henry Utila
This paper presents estimates of activity data, emission factors and emissions and removals for Malawi’s three REDD+ activities: deforestation, forest degradation, and enhancement. Calculations are based on data from Malawi’s National Forest Inventory (NFI) and plantation data for the reference period 2010 to 2020. Deforestation occurred at a rate of 11,565ha ± 1,067ha per year, representing a 0.66% annual change. Notably, deforestation was higher in non-protected areas (0.69%) than protected areas (0.66%). Forest degradation resulted in an annual loss of 14,192 ha, equivalent to 0.77% per annum, with 54% degradation occurring in protected areas, mainly within the dense canopy class (>60%). These protected areas had an area weighted carbon stock of 57.26 tC/ha while forests outside the protected areas had an average carbon stock of 45.03 tC/ha. The estimated annual emissions from deforestation and forest degradation were 1,008,600 and 543,511 tCO2e/yr, respectively. Annual removal due to forest enhancement averaged 61,070 tCO2e/yr. The mean net forest emissions for this reference period were 1,491,041 tCO2e/yr. Malawi has the potential to enhance its forests and mitigate its emissions through industrial plantations while also abating forest and biodiversity loss through avoided deforestation and forest degradation. By using Collect Earth, a free and open source platform, this analysis provides a model for emissions and removals assessments that are transparent, fully replicable, and cost-effective for governments.
This paper presents estimates of activity data, emission factors and emissions and removals for Malawi’s three REDD+ activities: deforestation, forest degradation, and enhancement. Calculations are based on data from Malawi’s National Forest Inventory (NFI) and plantation data for the reference period 2010 to 2020. Deforestation occurred at a rate of 11,565ha ± 1,067ha per year, representing a 0.66% annual change. Notably, deforestation was higher in non-protected areas (0.69%) than protected areas (0.66%). Forest degradation resulted in an annual loss of 14,192 ha, equivalent to 0.77% per annum, with 54% degradation occurring in protected areas, mainly within the dense canopy class (>60%). These protected areas had an area weighted carbon stock of 57.26 tC/ha while forests outside the protected areas had an average carbon stock of 45.03 tC/ha. The estimated annual emissions from deforestation and forest degradation were 1,008,600 and 543,511 tCO2e/yr, respectively. Annual removal due to forest enhancement averaged 61,070 tCO2e/yr. The mean net forest emissions for this reference period were 1,491,041 tCO2e/yr. Malawi has the potential to enhance its forests and mitigate its emissions through industrial plantations while also abating forest and biodiversity loss through avoided deforestation and forest degradation. By using Collect Earth, a free and open source platform, this analysis provides a model for emissions and removals assessments that are transparent, fully replicable, and cost-effective for governments.
Posted: 05 December 2024
Soil Moisture Retrieval Based on Ensemble Learning Models Using Landsat8 Data in Areas of High Heterogeneity
Qingxia Wu,
Zhongli Zhu,
Julong Ma,
Shaomin Liu,
Linna Chai,
Ziwei Xu
Posted: 05 December 2024
Assessment of the Potential of Small Beads Reservoirs to Mitigate Climate Change Impacts in Urban Areas
Wanda Jarosz,
Witold Mandrysz,
Barbara Kalinowska-Wójcik,
Jakub Grudniewski,
Natalia Janczewska,
Edyta Sierka,
Damian Absalon,
Łukasz Pieron,
Marcin Lipowczan,
Anna Piekarska-Stachowiak
This study examines historical water management practices as a means of addressing climate change, focusing on the Tyski Stream catchment in Upper Silesia, Poland a region marked by ex-tensive urbanization and industrial evolution. It investigates the effectiveness of historical hydro-technical systems, such as bead-like ponds from the 15th to 18th centuries, in enhancing water retention, reducing flood risks, and supporting ecosystem services. in a critical period, over 54 years (1827-1881), the number of reservoirs decreased from 142 to 31 (the area of ponds decreased from 161 to 32 ha). This was related to progressive industrialization, urban sprawl, and changes in legal frameworks, such as land ownership laws, leading to ecosystem degradation, loss of biodiversity, and altered hydrological processes. The research emphasizes the potential of reviving historical water management systems on natural processes to mitigate the impacts of climate change. By analyzing historical cartographic resources, the study assesses the feasibility of reconstructing lake systems in areas with similar topographic and hydrological features. It also stresses the necessity of community engagement and securing widespread social and political support to ensure public acceptance and the success of renaturation initiatives. The findings indicate that restoring these systems can offer diverse benefits, including improved water management, enhanced biodiversity, and greater urban resilience, while addressing the socio-political complexities of implementing large-scale environmental restoration projects.
This study examines historical water management practices as a means of addressing climate change, focusing on the Tyski Stream catchment in Upper Silesia, Poland a region marked by ex-tensive urbanization and industrial evolution. It investigates the effectiveness of historical hydro-technical systems, such as bead-like ponds from the 15th to 18th centuries, in enhancing water retention, reducing flood risks, and supporting ecosystem services. in a critical period, over 54 years (1827-1881), the number of reservoirs decreased from 142 to 31 (the area of ponds decreased from 161 to 32 ha). This was related to progressive industrialization, urban sprawl, and changes in legal frameworks, such as land ownership laws, leading to ecosystem degradation, loss of biodiversity, and altered hydrological processes. The research emphasizes the potential of reviving historical water management systems on natural processes to mitigate the impacts of climate change. By analyzing historical cartographic resources, the study assesses the feasibility of reconstructing lake systems in areas with similar topographic and hydrological features. It also stresses the necessity of community engagement and securing widespread social and political support to ensure public acceptance and the success of renaturation initiatives. The findings indicate that restoring these systems can offer diverse benefits, including improved water management, enhanced biodiversity, and greater urban resilience, while addressing the socio-political complexities of implementing large-scale environmental restoration projects.
Posted: 05 December 2024
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