Pub Date : 2023-08-07DOI: 10.21577/0100-4042.20170970
Raquel Oliveira, H. Affe, Raquel Avelina, Luana Pinho, Thiago Franklin, Gizyelle Miguel, Letícia Krobel Da Cunha
SOURCE OR SINK? A REVIEW OF THE CO2 FLUXES AT THE BRAZILIAN CONTINENTAL SHELF. Studies of global carbon balance estimates are still incipient in the oceans of the Southern Hemisphere, mainly in coastal areas and continental shelf. Even in Brazil, despite its continental proportion coastline, there is still a great inconsistency in studies on the marine carbonate system and CO2 fluxes at the air-sea interface. This article presents a review of studies on CO2 fluxes on the coast of Brazil, published between the years 2000 and 2022, aiming to map the distribution of CO2 fluxes on the Brazilian continental shelf, to understand its role as a source or sink of CO2. In general, large-scale studies show that the Brazilian shelf exhibits a latitudinal variation of air-sea CO2 fluxes, behaving mainly as a source in the north, where there is no influence of the Amazon River plume, and as a sink in the south portion. We also identified there is a strong influence on the occurrence of mesoscale and synoptic oceanographic and meteorological events, and the presence of different ecosystems, which can change the behavior of CO2 fluxes locally. However, there are still many data gaps along the continental shelf, as well as in different seasons for the entire coast.
{"title":"FONTE OU SUMIDOURO? UMA REVISÃO SOBRE OS FLUXOS DE CO2 NA PLATAFORMA CONTINENTAL BRASILEIRA","authors":"Raquel Oliveira, H. Affe, Raquel Avelina, Luana Pinho, Thiago Franklin, Gizyelle Miguel, Letícia Krobel Da Cunha","doi":"10.21577/0100-4042.20170970","DOIUrl":"https://doi.org/10.21577/0100-4042.20170970","url":null,"abstract":"SOURCE OR SINK? A REVIEW OF THE CO2 FLUXES AT THE BRAZILIAN CONTINENTAL SHELF. Studies of global carbon balance estimates are still incipient in the oceans of the Southern Hemisphere, mainly in coastal areas and continental shelf. Even in Brazil, despite its continental proportion coastline, there is still a great inconsistency in studies on the marine carbonate system and CO2 fluxes at the air-sea interface. This article presents a review of studies on CO2 fluxes on the coast of Brazil, published between the years 2000 and 2022, aiming to map the distribution of CO2 fluxes on the Brazilian continental shelf, to understand its role as a source or sink of CO2. In general, large-scale studies show that the Brazilian shelf exhibits a latitudinal variation of air-sea CO2 fluxes, behaving mainly as a source in the north, where there is no influence of the Amazon River plume, and as a sink in the south portion. We also identified there is a strong influence on the occurrence of mesoscale and synoptic oceanographic and meteorological events, and the presence of different ecosystems, which can change the behavior of CO2 fluxes locally. However, there are still many data gaps along the continental shelf, as well as in different seasons for the entire coast.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68268888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-07DOI: 10.21577/0100-4042.20230054
E. Braga, L. Lucena, A. Almeida, M. Pires, J. do Nascimento, B. Sutti, G. Berbel, V. Chiozzini
THE ESTUARINE ENVIRONMENT AND pH VARIATION: NATURAL LIMTS AND EXPERIMENTAL OBSERVATION OF THE ACIDIFICATION EFFECT ON PHOSPHORUS BIOAVAILABILITY. This study shows the variation of pH in the Cananéia-Iguape Estuarine-Lagoon Complex (CIELC). Data from 3 years (2019, 2021, 2022) were obtained in 17 points presenting the following ranges: temperature (14.88-27.05 ºC), pH (7.16-8.40) and DIP (0.20-11.28 µmol L-1) along a saline gradient (0.05-32.09) under different hydrodynamics, biogeochemical processes and anthropogenic influence. The pH buffering capacity due to the presence of weak acid salts in saline water (S ≥ 30) was associated to the lowest DIP, decreasing with low salinity values, confirming the direct correlation among salinity and pH. The highest temperatures in the winter of 2021, corroborated with the abnormal climate event in that year. An in vitro experiment showed results of the interaction of PID and sediments with different textures, with and without the presence of the benthic microbiota under a considerable decreasing of the pH (acidification) in relation to the natural condition of this environment. The P sediment flux characterized Iguape sector as a P sink with or without biota, Ararapira sector as a P source with biota and Cananéia, as P source without biota. The salt water buffered the pH and sediment buffered DIP both associated to the biogeochemical and hydrodynamic processes contribute to the homeostasis in the system.
{"title":"O AMBIENTE ESTUARINO E A VARIAÇÃO DE pH: LIMITES NATURAIS E OBSERVAÇÃO EXPERIMENTAL DO EFEITO DA ACIDIFICAÇÃO SOBRE A BIODISPONIBILIDADE DE FÓSFORO","authors":"E. Braga, L. Lucena, A. Almeida, M. Pires, J. do Nascimento, B. Sutti, G. Berbel, V. Chiozzini","doi":"10.21577/0100-4042.20230054","DOIUrl":"https://doi.org/10.21577/0100-4042.20230054","url":null,"abstract":"THE ESTUARINE ENVIRONMENT AND pH VARIATION: NATURAL LIMTS AND EXPERIMENTAL OBSERVATION OF THE ACIDIFICATION EFFECT ON PHOSPHORUS BIOAVAILABILITY. This study shows the variation of pH in the Cananéia-Iguape Estuarine-Lagoon Complex (CIELC). Data from 3 years (2019, 2021, 2022) were obtained in 17 points presenting the following ranges: temperature (14.88-27.05 ºC), pH (7.16-8.40) and DIP (0.20-11.28 µmol L-1) along a saline gradient (0.05-32.09) under different hydrodynamics, biogeochemical processes and anthropogenic influence. The pH buffering capacity due to the presence of weak acid salts in saline water (S ≥ 30) was associated to the lowest DIP, decreasing with low salinity values, confirming the direct correlation among salinity and pH. The highest temperatures in the winter of 2021, corroborated with the abnormal climate event in that year. An in vitro experiment showed results of the interaction of PID and sediments with different textures, with and without the presence of the benthic microbiota under a considerable decreasing of the pH (acidification) in relation to the natural condition of this environment. The P sediment flux characterized Iguape sector as a P sink with or without biota, Ararapira sector as a P source with biota and Cananéia, as P source without biota. The salt water buffered the pH and sediment buffered DIP both associated to the biogeochemical and hydrodynamic processes contribute to the homeostasis in the system.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68272425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-07DOI: 10.21577/0100-4042.20230063
Sabrina T. Martinez, Jeancarlo Pereira Dos Anjos, P. Pereira, L. Guarieiro, Gisele da Rocha
ORGANIC AND INORGANIC BIOMARKERS OF ATMOSPHERIC AEROSOLS FROM MARINE REGIONS. In this study, we overview the recent advancements in knowledge regarding organic and inorganic biomarkers of atmospheric aerosols from coastal zones and open marine areas. It deals with the interaction between the ocean and the atmosphere through their interface, the formation of a seawater microlayer (SML) and the exchange of a myriad of chemical compounds between those environmental compartments. We also discuss how marine aerosols (MAs) are intrinsically related to the global carbon cycle, influence the radiative budget of the Earth, and are related to global climate. At the end, we discuss the trends of new studies on the topic.
{"title":"BIOMARCADORES ORGÂNICOS E INORGÂNICOS DE AEROSSÓIS ATMOSFÉRICOS DE REGIÕES MARINHAS","authors":"Sabrina T. Martinez, Jeancarlo Pereira Dos Anjos, P. Pereira, L. Guarieiro, Gisele da Rocha","doi":"10.21577/0100-4042.20230063","DOIUrl":"https://doi.org/10.21577/0100-4042.20230063","url":null,"abstract":"ORGANIC AND INORGANIC BIOMARKERS OF ATMOSPHERIC AEROSOLS FROM MARINE REGIONS. In this study, we overview the recent advancements in knowledge regarding organic and inorganic biomarkers of atmospheric aerosols from coastal zones and open marine areas. It deals with the interaction between the ocean and the atmosphere through their interface, the formation of a seawater microlayer (SML) and the exchange of a myriad of chemical compounds between those environmental compartments. We also discuss how marine aerosols (MAs) are intrinsically related to the global carbon cycle, influence the radiative budget of the Earth, and are related to global climate. At the end, we discuss the trends of new studies on the topic.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68272405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-07DOI: 10.21577/0100-4042.20230056
J. Santana, Iasmim Leal, Antônio Queiroz, Henrique Assumpção, J. D. De Souza, M. Zucchi, Ana de Albergaria-Barbosa
ORGANIC MATTER SOURCES TO THE SUPERFICIAL SEDIMENT OF THE ITAPICURU RIVER ESTUARY (BAHIA - BRAZIL). The present study evaluated the sources of organic matter (O.M.) in the Itapicuru River estuary (IRE), which is in an environmentally protected area surrounded by the Atlantic Rainforest in the northeast of Brazil. Eleven sediment samples were collected along the study area. Total organic carbon (TOC) and the δ13C values were determined using an elemental analyzer coupled with an isotope ratio mass spectrometer. The n-alkanes composition was evaluated through gas chromatography coupled to a flame ionization detector. TOC and total n-alkanes concentrations ranged, respectively, from not detected to 0.72%, and from lower the limit of detection to 5024 ng g-1. There was a significant concentration of n-C22 and n-C24 in some samples showing bacterial production and recycling of O.M. Values of δ13C ranged from −27.6 to −21.9‰. Carbon preference index, terrestrial-aquatic ratio, aquatic production index, average chain length, and the ratio between n-C29 and n-C31 values ranged, respectively, from 1.42 to 4.11; 2.82 to 9.40; 0.00 to 0.25; 27.7 to 29.9; and 0.27 to 0.43. These results show that concentrations of O.M. to IRE are low, and its main source is C3 plants, such as those from mangroves. There is also the contribution of macrophytes.
{"title":"FONTES DE MATÉRIA ORGÂNICA PARA OS SEDIMENTOS SUPERFICIAIS DO ESTUÁRIO DO RIO ITAPICURU (BAHIA - BRASIL)","authors":"J. Santana, Iasmim Leal, Antônio Queiroz, Henrique Assumpção, J. D. De Souza, M. Zucchi, Ana de Albergaria-Barbosa","doi":"10.21577/0100-4042.20230056","DOIUrl":"https://doi.org/10.21577/0100-4042.20230056","url":null,"abstract":"ORGANIC MATTER SOURCES TO THE SUPERFICIAL SEDIMENT OF THE ITAPICURU RIVER ESTUARY (BAHIA - BRAZIL). The present study evaluated the sources of organic matter (O.M.) in the Itapicuru River estuary (IRE), which is in an environmentally protected area surrounded by the Atlantic Rainforest in the northeast of Brazil. Eleven sediment samples were collected along the study area. Total organic carbon (TOC) and the δ13C values were determined using an elemental analyzer coupled with an isotope ratio mass spectrometer. The n-alkanes composition was evaluated through gas chromatography coupled to a flame ionization detector. TOC and total n-alkanes concentrations ranged, respectively, from not detected to 0.72%, and from lower the limit of detection to 5024 ng g-1. There was a significant concentration of n-C22 and n-C24 in some samples showing bacterial production and recycling of O.M. Values of δ13C ranged from −27.6 to −21.9‰. Carbon preference index, terrestrial-aquatic ratio, aquatic production index, average chain length, and the ratio between n-C29 and n-C31 values ranged, respectively, from 1.42 to 4.11; 2.82 to 9.40; 0.00 to 0.25; 27.7 to 29.9; and 0.27 to 0.43. These results show that concentrations of O.M. to IRE are low, and its main source is C3 plants, such as those from mangroves. There is also the contribution of macrophytes.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68272566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-07DOI: 10.21577/0100-4042.20230069
Jailson de Andrade, Gisele da Rocha, N. Morgon
{"title":"O PAPEL CENTRAL DA DÉCADA DA CIÊNCIA OCEÂNICA PARA O DESENVOLVIMENTO SUSTENTÁVEL E O FUTURO DO PLANETA","authors":"Jailson de Andrade, Gisele da Rocha, N. Morgon","doi":"10.21577/0100-4042.20230069","DOIUrl":"https://doi.org/10.21577/0100-4042.20230069","url":null,"abstract":"","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68272891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-07DOI: 10.21577/0100-4042.20230066
Maria Tereza de Souza, Vanessa Sales-Shimomoto, G. D. da Silva, A. Val
Plastic pollution is causing worldwide concern, especially after evidence that the various types of plastic degrade into particles of smaller sizes; known as micro- and nanoplastics. The origin of the plastics in the environment is related to human actions. The objective of this review is to describe the main routes of microplastic input in the Amazonian rivers and how local environmental characteristics can affect the transformation of plastics into microplastics until their absorption by aquatic organisms. The current situation regarding the presence of microplastic particles in freshwater is analyzed considering the environmental dynamics of the region, and focuses on rivers, estuaries and sediments, their effects on organisms, especially on fish, followed by the transportation of microplastic particles to the sea. Amapá, Amazonas, Pará and Mato-Grosso are the states of the Brazilian Amazon with scientific reports on the characterization of microplastic particles in sediment, water, and fish. These studies are local and descriptive and most of them highlight the characterization of microplastics. There is a need for field research in the various microregions of the Amazon, as well as actions to mitigate the damage, including to riverine populations, that is caused by these pollutants in the region.
{"title":"MICROPLASTICS AND THE AMAZON: FROM THE RIVERS TO THE ESTUARY","authors":"Maria Tereza de Souza, Vanessa Sales-Shimomoto, G. D. da Silva, A. Val","doi":"10.21577/0100-4042.20230066","DOIUrl":"https://doi.org/10.21577/0100-4042.20230066","url":null,"abstract":"Plastic pollution is causing worldwide concern, especially after evidence that the various types of plastic degrade into particles of smaller sizes; known as micro- and nanoplastics. The origin of the plastics in the environment is related to human actions. The objective of this review is to describe the main routes of microplastic input in the Amazonian rivers and how local environmental characteristics can affect the transformation of plastics into microplastics until their absorption by aquatic organisms. The current situation regarding the presence of microplastic particles in freshwater is analyzed considering the environmental dynamics of the region, and focuses on rivers, estuaries and sediments, their effects on organisms, especially on fish, followed by the transportation of microplastic particles to the sea. Amapá, Amazonas, Pará and Mato-Grosso are the states of the Brazilian Amazon with scientific reports on the characterization of microplastic particles in sediment, water, and fish. These studies are local and descriptive and most of them highlight the characterization of microplastics. There is a need for field research in the various microregions of the Amazon, as well as actions to mitigate the damage, including to riverine populations, that is caused by these pollutants in the region.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68273157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-07DOI: 10.21577/0100-4042.20230049
Julián Leonel, R. Nascimento, Daniele Miranda
PERFLUORINATED COMPOUNDS: A THREAT TO THE CLEAN OCEAN. Per- and polyfluorinated compounds (PFAS) have been produced for more than seven decades and widely used in the most diverse areas, from food packaging, textile industry, aqueous film-forming foam to pesticides and surfactants. However, the characteristics that allow the wide range of applications also bring environmental concerns due to their persistence and toxic effects. Although the ocean might be the final destination of PFAS, in Brazil few studies have been carried out about PFAS and there are many gaps regarding their environmental occurrence, sources and distribution. Therefore, this article presents a review of the production, use, behavior in the environment, legislation, the occurrence of classic PFAS in the Brazilian marine environment, as well as perceptions about their fluorinated substitutes.
{"title":"COMPOSTOS PERFLUORADOS: UMA AMEAÇA AO OCEANO LIMPO","authors":"Julián Leonel, R. Nascimento, Daniele Miranda","doi":"10.21577/0100-4042.20230049","DOIUrl":"https://doi.org/10.21577/0100-4042.20230049","url":null,"abstract":"PERFLUORINATED COMPOUNDS: A THREAT TO THE CLEAN OCEAN. Per- and polyfluorinated compounds (PFAS) have been produced for more than seven decades and widely used in the most diverse areas, from food packaging, textile industry, aqueous film-forming foam to pesticides and surfactants. However, the characteristics that allow the wide range of applications also bring environmental concerns due to their persistence and toxic effects. Although the ocean might be the final destination of PFAS, in Brazil few studies have been carried out about PFAS and there are many gaps regarding their environmental occurrence, sources and distribution. Therefore, this article presents a review of the production, use, behavior in the environment, legislation, the occurrence of classic PFAS in the Brazilian marine environment, as well as perceptions about their fluorinated substitutes.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68271915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-07DOI: 10.21577/0100-4042.20230058
C. Noriega, M. Araújo, H. Varona, M. Costa, Amilcar E. Calzada, C. Medeiros, A. Silva, L. Portela, D. Bezerra, Rivaldo Jeronimo, Paulo Barros, J. Araujo, M. Rollnic
Multiple environmental problems are caused by the accumulation of nitrogen (N) and phosphorus (P) in river water on its way to the ocean. The objective of this work was to determine the N and P loads in 12 hydrographic basins that flow into estuaries along the northeastern coast of Brazil using established methods. Additionally, natural and anthropogenic loads trends in the hydrographic basins of 12 tropical rivers in northeastern Brazil over 27 years (1990-2016) were evaluated. The results indicated an annual average increase of +1.1% in population density, while precipitation showed no significant trend. The anthropogenic loads were 21 and 112 times higher than natural inputs for N and P, respectively. Anthropogenic sources accounted for ~ 96% of all contributions. The positive trends of these loads (mainly wastewater) represented an annual average increase of 1.1% for N and 1.2% for P, for all river basins included in this study. These percentages represent average annual loads of 251 t N yr-1 and 54.8 t P yr-1. The time series of N and P in the study region showed trends that point to a constant increase, implying a greater contribution of these loads to the adjacent coastal region year after year.
在流向海洋的河流中，氮和磷的积累会引起多种环境问题。这项工作的目的是利用既定的方法确定流入巴西东北海岸河口的12个水文盆地的N和P负荷。此外，对巴西东北部12条热带河流流域27年来(1990-2016年)的自然和人为负荷趋势进行了评估。结果表明，人口密度年平均增长+1.1%，降水量变化趋势不明显。人工负荷分别是自然输入量的21倍和112倍。人为来源占所有贡献的约96%。这些负荷(主要是废水)的积极趋势表明，在本研究包括的所有流域中，氮和磷的年平均增幅分别为1.1%和1.2%。这些百分比代表年平均负荷为251 t N -1和54.8 t P -1。研究区N和P的时间序列呈现出不断增加的趋势，表明这些负荷对邻近沿海地区的贡献逐年增大。
{"title":"LONG-TERM TREND OF NITROGEN AND PHOSPHORUS TRANSPORT IN 12 TROPICAL COASTAL WATERSHEDS IN NORTHEAST BRAZIL","authors":"C. Noriega, M. Araújo, H. Varona, M. Costa, Amilcar E. Calzada, C. Medeiros, A. Silva, L. Portela, D. Bezerra, Rivaldo Jeronimo, Paulo Barros, J. Araujo, M. Rollnic","doi":"10.21577/0100-4042.20230058","DOIUrl":"https://doi.org/10.21577/0100-4042.20230058","url":null,"abstract":"Multiple environmental problems are caused by the accumulation of nitrogen (N) and phosphorus (P) in river water on its way to the ocean. The objective of this work was to determine the N and P loads in 12 hydrographic basins that flow into estuaries along the northeastern coast of Brazil using established methods. Additionally, natural and anthropogenic loads trends in the hydrographic basins of 12 tropical rivers in northeastern Brazil over 27 years (1990-2016) were evaluated. The results indicated an annual average increase of +1.1% in population density, while precipitation showed no significant trend. The anthropogenic loads were 21 and 112 times higher than natural inputs for N and P, respectively. Anthropogenic sources accounted for ~ 96% of all contributions. The positive trends of these loads (mainly wastewater) represented an annual average increase of 1.1% for N and 1.2% for P, for all river basins included in this study. These percentages represent average annual loads of 251 t N yr-1 and 54.8 t P yr-1. The time series of N and P in the study region showed trends that point to a constant increase, implying a greater contribution of these loads to the adjacent coastal region year after year.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68272648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-07DOI: 10.21577/0100-4042.20230048
Rozane Marins, A. Carvalho, Agda da Silva, M. Cavalcante
EVALUATING DIRECT AND INDIRECT pCO2 MEASUREMENTS IN ESTUARINE ENVIRONMENTS. Estuaries are dynamic systems globally characterized as sources of CO2 to the atmosphere. However, they present large spatial-temporal variability in both pCO2 and FCO2. Increased CO2 emissions turns imperative to obtain continuous and accurate measurements of pCO2 in air and water to monitor FCO2 in these sensitive and complex environments. Currently, direct measurements of pCO2 and estimates of FCO2 in estuarine regions are still scarce and frequently the indirect pCO2 estimates are used that consists of measurements from at least two other parameters of the carbonate system: total alkalinity, dissolved inorganic carbon or pH. In this work, we evaluated recent direct and indirect measurements of pCO2 in the Jaguaribe River estuary-CE. This study provides a critical analysis of the data obtained through the two main methods mostly used to estimate pCO2, presenting the challenges towards greater consistency in obtaining data for a better understanding of the carbonate system in estuarine waters. We highlight the potential for continuous pCO2 measurements and long-term monitoring in coastal environments, contributing to improve knowledge of regional CO2 exchanges and to elucidate the role of estuaries in the global carbon cycle.
{"title":"AVALIAÇÃO DE MÉTODOS DIRETOS E INDIRETOS DE MEDIÇÃO DA pCO2 EM AMBIENTES ESTUARINOS","authors":"Rozane Marins, A. Carvalho, Agda da Silva, M. Cavalcante","doi":"10.21577/0100-4042.20230048","DOIUrl":"https://doi.org/10.21577/0100-4042.20230048","url":null,"abstract":"EVALUATING DIRECT AND INDIRECT pCO2 MEASUREMENTS IN ESTUARINE ENVIRONMENTS. Estuaries are dynamic systems globally characterized as sources of CO2 to the atmosphere. However, they present large spatial-temporal variability in both pCO2 and FCO2. Increased CO2 emissions turns imperative to obtain continuous and accurate measurements of pCO2 in air and water to monitor FCO2 in these sensitive and complex environments. Currently, direct measurements of pCO2 and estimates of FCO2 in estuarine regions are still scarce and frequently the indirect pCO2 estimates are used that consists of measurements from at least two other parameters of the carbonate system: total alkalinity, dissolved inorganic carbon or pH. In this work, we evaluated recent direct and indirect measurements of pCO2 in the Jaguaribe River estuary-CE. This study provides a critical analysis of the data obtained through the two main methods mostly used to estimate pCO2, presenting the challenges towards greater consistency in obtaining data for a better understanding of the carbonate system in estuarine waters. We highlight the potential for continuous pCO2 measurements and long-term monitoring in coastal environments, contributing to improve knowledge of regional CO2 exchanges and to elucidate the role of estuaries in the global carbon cycle.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68271852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-26DOI: 10.21577/0100-4042.20230023
Habdias Silva-Neto, Gerson Duarte-Junior, G. Bazílio, Juliana Parente-Rocha, D. Colugnati, C. Borges, Wendell Coltro
3D PRINTING OF MAGNETIC SEPARATOR: AN AFFORDABLE APPROACH TO SAMPLE PREPARATION IN THE COVID-19 DIAGNOSIS. This report describes the fabrication of a low-cost magnetic separator holder combining 3D printing and compact neodymium blocks for allowing magnetic extraction and purification of RNA from samples collected by nasopharyngeal swab from patients infected by SARS-CoV-2. The device was designed to contain 24 entrances for plastic microtubes in an arrangement like a commercial device. The proof of concept of the proposed device was successfully demonstrated through the sample extraction and purification of swab samples collected from eight patients suspected of SARS-CoV-2 infection. The sample preparation protocol was performed using a commercial kit containing magnetic beads and different solutions. The performance of the printed device was compared to a commercial magnetic separator, usually employed in the golden standard techniques. The fabrication of the 3D printed magnetic separator was completed under optimized printing conditions within 6 h at cost of 4 USD per unit. The RNA extracted from samples using both devices was analyzed by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and the achieved results have indicated no statistical different at confidence level of 95%. Based on the achievements, the use of 3D printing and neodymium blocks have demonstrated an alternative route to be used in routing analysis associated to COVID-19 diagnosis.
{"title":"IMPRESSÃO 3D DE SEPARADOR MAGNÉTICO: UMA ABORDAGEM ACESSÍVEL PARA O PREPARO DE AMOSTRAS NO DIAGNÓSTICO DA COVID-19","authors":"Habdias Silva-Neto, Gerson Duarte-Junior, G. Bazílio, Juliana Parente-Rocha, D. Colugnati, C. Borges, Wendell Coltro","doi":"10.21577/0100-4042.20230023","DOIUrl":"https://doi.org/10.21577/0100-4042.20230023","url":null,"abstract":"3D PRINTING OF MAGNETIC SEPARATOR: AN AFFORDABLE APPROACH TO SAMPLE PREPARATION IN THE COVID-19 DIAGNOSIS. This report describes the fabrication of a low-cost magnetic separator holder combining 3D printing and compact neodymium blocks for allowing magnetic extraction and purification of RNA from samples collected by nasopharyngeal swab from patients infected by SARS-CoV-2. The device was designed to contain 24 entrances for plastic microtubes in an arrangement like a commercial device. The proof of concept of the proposed device was successfully demonstrated through the sample extraction and purification of swab samples collected from eight patients suspected of SARS-CoV-2 infection. The sample preparation protocol was performed using a commercial kit containing magnetic beads and different solutions. The performance of the printed device was compared to a commercial magnetic separator, usually employed in the golden standard techniques. The fabrication of the 3D printed magnetic separator was completed under optimized printing conditions within 6 h at cost of 4 USD per unit. The RNA extracted from samples using both devices was analyzed by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and the achieved results have indicated no statistical different at confidence level of 95%. Based on the achievements, the use of 3D printing and neodymium blocks have demonstrated an alternative route to be used in routing analysis associated to COVID-19 diagnosis.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68271001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：