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Innovations offered by the agricultural actors of the south pacific of Nicaragua and their implementation in the family farming production systems period 2015-2020 | Innovaciones ofertadas por los actores agropecuarios del pacífico sur de Nicaragua y su implementación en los sistemas de producción de la agricultura familiar período 2015-2020 Texto completo
2021
Guzmán Gómez, Mauricio Antonio | Pedroza Pacheco, Manuel Enrique
In order to analyze the innovation technologies offered by different actors in the South Pacific of Nicaragua that could be implemented in family farming production systems and contribute to the improvement of their production and productivity, a research was carried out with a Mixed Approach, which integrated quantitative methods and qualitative: univariate statistical analysis, interviews with seven officials from institutions and organizations in the territory; three focus groups. Quantitative data were collected from 380 surveys of producers in southern Nicaragua. The reductive analysis of the qualitative information, provided by the participating actors, was implemented. The main results obtained and conclusions were: the population under study were small agricultural producers, the agricultural area has an average of 2.83 mz. 46% of the producers in the production systems are Leading Producers; 37% are members of Community Seed Bank; 16% are owners of Research and Technological Innovation Farms. 71% of the producers implemented some type of innovation that has been adopted by another producer; These producers affirmed that the innovations are helping to improve the production of their crops. The main technologies offered by the Institutions and other actors in the territory were: three for Basic Grains, four for Major and Minor Livestock, two for IPM Practices, five for OCS and A Implementation, and eight for Agro-socioeconomic Practices. | Con el objetivo de analizar las tecnologías de innovación ofertadas por diferentes actores del Pacifico Sur de Nicaragua que pudieran implementarse en sistemas de producción de agricultura familiar y contribuir al mejoramiento de su producción y productividad, se realizó una investigación con Enfoque Mixto, que integró métodos cuantitativos y cualitativos: análisis estadístico univariado, entrevistas a siete funcionarios de instituciones y organismos del territorio; tres grupos focales. Los datos cuantitativos se recolectaron a partir de 380 encuestas a productores (as) del sur de Nicaragua. Se implementó el análisis reductivo de la información cualitativa, aportada por los actores participantes. Los principales resultados obtenidos fueron: la población en estudio, fueron pequeños productores (as) agropecuarios, el área agrícola presenta un promedio de 2.83 mz. El 46% de los productores (as) en los sistemas de producción, son Productores Protagonistas; el 37% son miembros de Banco Comunitarios de Semilla; un 16% son propietarios de Fincas de Investigación e Innovación Tecnológica. El 71% de los productores (as), implementaron algún tipo de innovación que ha sido adoptada por otro productor (a); estos productores (as) afirmaron que las innovaciones están contribuyendo a mejorar la producción en sus cultivos. Las principales tecnologías ofertadas por las Instituciones y otros actores del territorio fueron: tres de Granos básicos, cuatro de Ganadería mayor y menor, dos de Practicas MIP, cinco de Implementación de OCS y A y ocho de Prácticas agro socioeconómica.
Mostrar más [+] Menos [-]Extraction of oleoresin from turmeric (curcuma longa) using ethanol as solvent | Extracción de oleorresina de cúrcuma (cúrcuma longa) utilizando etanol como solvente Texto completo
2021
Blandón Navarro, Sandra Lorena | Ponce Arévalo , Carlos Mario
This study aimed to evaluate the turmeric oleoresin extraction process using ethanol (97% by volume) as solvent. In this sense, oleoresin extraction experiments were carried out using dry turmeric (moisture 13 %) with a particle size of 4.75 mm as raw material. The extraction time was 24 hours at 40 °C. The results showed that the oleoresin extraction yield of 3.18 ± 0.14% was influenced by the coarse particle size of the raw material, since it was lower than that reported in previous studies, where ground turmeric with a particle size less than 500 μm was used. In relation to the amount of solution adhered to the residual turmeric solid, it was determined that it was 1.51 ± 0.20 g of solution/g of solids. From the results it can be inferred that the use of ethanol in the extraction of oleoresin is technically feasible, however, its performance is influenced by the characteristics of the raw material and the pretreatment of the solid material prior to the extraction stage (drying and reduction of size). | Este estudio tuvo como objetivo evaluar el proceso de extracción de la oleorresina de cúrcuma utilizando etanol (97 % en volumen) como solvente. En este sentido, se llevaron a cabo experimentos de extracción de la oleorresina usando como materia prima la cúrcuma seca (13 % de humedad) con granulometría de 4.75 mm. El tiempo de extracción fue de 24 horas a 40 °C. Los resultados mostraron que el rendimiento de extracción de la oleorresina de 3.18 ± 0.14% fue influenciado por la granulometría gruesa de la materia prima, dado que fue menor al reportado en estudios previos, donde se utilizó cúrcuma molida con granulometría menor a 500 μm. En relación a la cantidad de solución adherida al sólido residual de cúrcuma se determinó que fue de 1.51 ± 0.20 g de solución/ g de sólidos. De los resultados se puede inferir que el uso de etanol en la extracción de oleorresina es técnicamente viable, sin embargo, su desempeño está influenciado por las características de la materia prima y el pretratamiento del material sólido anterior a la etapa de extracción (secado y reducción de tamaño).
Mostrar más [+] Menos [-]Culvert design for aquatic organism passage: an enviromental approach | Diseño de alcantarilla para el paso de organismos acuáticos: un enfoque ambiental Texto completo
2021
Blanco Chávez, Miguel Enrique
The design of culverts at the crossroads of roads and streams such as streams or rivers, has traditionally been based on the hydraulic safety requirements for the road. With this conception of the sewer design, the biological elements of the water stream, such as fish and other aquatic organisms, which are an essential part of the ecosystem and which have been altered by a physical barrier that is the sewer, have been left without consideration. Thinking about environmentally friendly design, concepts and guidelines have been developed for the design of culverts to cross roads and streams, which facilitate the passage of aquatic organisms through the culvert, so that these can have mobility in the same way as in the natural stream. In this paper some guidelines for the design of culverts in an environmentally friendly way are presented, which are addressed by Kilgore et al (2010), Schall at al. (2012), Bates and Kirn (2009), Henrik et al (2019), Kozarek and Mielke (2015), Olson et al (2017), and Vermont Department of Fish and Wildlife (2016). | El diseño de las alcantarillas en el cruce de carreteras y corrientes de agua como quebradas o ríos, se ha basado tradicionalmente en los requisitos hidráulicos de seguridad para la carretera. Con esta concepción del diseño de alcantarilla se ha dejado sin consideración los elementos biológicos de la corriente de agua, tal como los peces y otros organismos acuáticos, los cuales son parte esencial del ecosistema y que ha sido alterado por una barrera física que es la alcantarilla. Incluso, algunos factores físicos también son alterados, como la erosión o deposición de sedimentos y detritos, los cuales cambian igualmente las condiciones ambientales para los peces, dando como resultado, barreras que le impiden el desarrollo natural de su ciclo de vida, y ponen en peligro su reproducción. Pensando en el diseño amigable con el medio ambiente, se han desarrollado conceptos y lineamientos para el diseño de alcantarillas de cruce de carreteras y corrientes de agua, que faciliten el pase de los organismos acuáticos a través de la alcantarilla, de modo que estos puedan tener movilidad de la misma forma que en la corriente natural. En este escrito se presentan algunos lineamientos para el diseño de alcantarillas de forma amigable con el medio ambiente, los que son abordados por Kilgore et al (2010), Schall at al. (2012), Bates y Kirn (2009), Henrik et al (2019), Kozarek y Mielke (2015), Olson et al (2017) y Departamento de Pesca y Vida Silvestre de Vermont (2016).
Mostrar más [+] Menos [-]Air quality in three sites with high vehicular traffic in district one of the city of Managua | Calidad del aire en tres sitios de alto tráfico vehicular en el distrito uno de la ciudad de Managua Texto completo
2021
Mejía Martínez, Norlan Javier | Navarrete Pavón, Diana Maribel | Dávila Altamirano, Roberto José
This research was carried out with the objective of evaluating air quality with respect to three atmospheric pollutants, particulate matter less than or equal to 10 microns (PM10), nitrogen dioxide (NO2) and ozone (O3) in three sites with high vehicular traffic in district one of the city of Managua through measurement with automatic equipment that allows knowing the behavior of pollutants in real time. The monitoring was carried out between October 2017 to January 2018 with a frequency of two samplings per month. Based on the concentrations of atmospheric pollutants under study, it was determined that the concentrations of PM10, nitrogen dioxide (and ozone increase from October 2017 (rainy season) to January 2018 (dry season). PM10 and nitrogen dioxide concentrations do not exceed the maximum permissible limit established in NTON 05 012-02 during the four months of measurement, while ozone concentrations exceed the NTON regulations in November and December 2017 as well like January 2018. | La presente investigación se realizó con el objetivo de evaluar la calidad del aire con respecto a tres contaminantes atmosféricos, material particulado menor o igual a 10 micras (PM10), dióxido de nitrógeno (NO2) y ozono (O3) en tres sitios de alto tráfico vehicular en el distrito uno de la ciudad de Managua, a través de la medición con equipos automáticos que permiten conocer el comportamiento de los contaminantes en tiempo real. Los monitoreos se realizaron entre octubre 2017 a enero 2018 con una frecuencia de dos muestreos por mes. En base a las concentraciones de contaminantes atmosféricos en el estudio se determinó que las concentraciones de PM10, dióxido de nitrógeno y ozono aumentan desde octubre 2017 (estación lluviosa) a enero 2018 (estación seca). Las concentraciones de PM10 y dióxido de nitrógeno no exceden el límite máximo permisible establecido en la NTON 05 012-02 durante los cuatro meses de medición, mientras que las concentraciones de ozono exceden la normativa de la NTON en los meses de noviembre y diciembre 2017 así como enero 2018.
Mostrar más [+] Menos [-]Morphological and molecular identification of native trichoderma spp. Isolated from soils of agricultural importance | Identificación morfológica y molecular de especies autóctonas trichoderma spp., aisladas de suelos de importancia agrícola Texto completo
2021
Sánchez Miranda, María Delfina | Moreno Mayorga, Luis Francisco | Páramo Aguilera, Leandro Alberto
Trichoderma sp. is a genus of fungus that is being used widely as a sustainable alternative for the control of plant diseases and growth promoter in crops of agricultural importance. It has a great genetic diversity Therefore, this study aims to identify and describe morphologically and molecularly species from different sources as diverse as agricultural soil, crushed tomato, plantain cultivation, pastures, among others. In the study, 17 fungal isolates were found with characteristics in their colonies similar to Trichoderma spp.Which after observing their morphological characteristics were presumptively identified as belonging to this genus. The characterization of its conidiophore, phialides and conidia, showed that these isolates corresponded to the genus Trichoderma spp. Subsequently, it was demonstrated that, the 17 isolates belonged to the genus Trichoderma sp by sequencing, using the ITS1 primers (5 TCC GTA GGT GAA CCT GCG G 3) rDNA, finding 7 different species of the fungus in the study, which were: T. harzianum, T. viride, T. asperellum, T. asperelloide, T. songyi, T. virens and T. brief. From these species, T. asperellum and T. harzianum, are of vital importance because they have been previously identified as effective agents for the biological control of diseases and plant growth promoters and a new door of research with T. breve and T. songyi, is opened since very little is known about the biotechnological application of these. | Trichoderma sp. es un género de hongo que está siendo utilizado ampliamente como una alternativa sostenible para el control de enfermedades de plantas y promotor de crecimiento en cultivos de importancia agrícola. Tiene una gran diversidad genética, por lo que el presente estudio pretende identificar y describir morfológica y molecularmente especies provenientes de diferentes fuentes tan diversas como suelo agrícola, tomate triturado, cultivo de plátano, pastos entre otros. En el estudio se encontró 17 aislados de hongos con características en sus colonias similares a Trichoderma spp., los cuales después de observar sus características morfológicas se identificaron presuntivamente como pertenecientes a este género. La caracterización de su conidióforo, fiálides y conidias, demostró que dichos aislados correspondían al género Trichoderma spp. Posteriormente se demostró que los 17 aislados pertenecían al género Trichoderma sp mediante secuenciación, utilizando los cebadores ITS1 (5 TCC GTA GGT GAA CCT GCG G 3) ADNr, encontrándose 7 especies diferentes del hongo en el estudio, las cuales fueron: T. harzianum, T. viride, T. asperellum, T. asperelloide, T. songyi, T. virens y T. breve. De estas especies T. asperellum y T. harzianum, son de vital importancia por ser previamente identificadas como efectivos agentes de control biológico de enfermedades y promotores de crecimiento de plantas y se abre una nueva puerta de investigación con T. breve y T. songyi, ya que muy poco se conoce sobre la aplicación biotecnológica de éstas.
Mostrar más [+] Menos [-]Vulnerable birds to collide against wind towers in Rivas, Nicaragua, before construction | Aves vulnerables a colisionar contra torres eólicas en Rivas, Nicaragua, antes de su construcción Texto completo
2021
Zolotoff Pallais, José Manuel
A Bird Vulnerability Index (BVI) and Potential Vulnerability Map (PVM) was applied to determine which are the most susceptible bird species to collide with wind towers and the riskiest sites, in a wind power plant south from the city of Rivas. Transects were placed in two areas where the towers would be placed: Grasslands without Trees and Grasslands with Trees. Transects were also made in adjacent habitats such as Lake Nicaragua Coast and Riparian Forest. The BVI was calculated with nine factors (Flight Height, Type of Flight, Wingspan, Weight, Status, Abundance, Reproductive Status, International and National Conservation Status). The total PVM was calculated from all detected species, and average PMV only using species that exceeded the specific BVI median. The risk of habitat collision was calculated by determining that less of 50th percentile is considered to be low risk, and high risk when the percentile is greater than 50. The highest vulnerability index is found in the species: Magnificent Frigatebird (Fregata magnificens), Black Vulture (Coragyps atratus), Turkey Vulture (Cathartes aura), Osprey (Pandion haliaetus), Crested Caracara (Caracara cheriway), Nicaraguan Grackle (Quiscalus nicaraguensis), and Great Heron (Ardea herodias). The riparian forest and grassland with trees are the sites with the highest risk of collision to install wind towers. The BVI and PVM are important tools that allow the identification of potential risks of bird collision with wind towers before their construction. | Se aplicó un Índice de Vulnerabilidad de Aves (IVA) y Mapa de Vulnerabilidad Potencial (MVP) para determinar cuáles son las especies de aves más susceptibles a colisionar con torres eólicas y los sitios con mayor riesgo, en una central eólica al sur de la ciudad de Rivas. Se colocaron transectos en dos zonas donde se colocarían las torres: Pastizales sin ‘Árboles y Pastizales con Árboles. También se realizaron transectos en hábitats adyacentes como Costa del lago de Nicaragua y Bosque Ripario. El IVA se calculó con nueve factores (altura de vuelo, tipo de vuelo, longitud de ala, peso, estatus, abundancia, estado reproductivo, estado de conservación internacional y nacional). Se calculó el MVP total a partir de todas las especies detectadas, y MVP medio solo utilizando las especies que superaron la mediana del IVA específico. El riesgo de colisión por hábitat se calculó determinando que menor al percentil 50 se considera de riesgo bajo, y de riesgo alto cuando el percentil sea mayor que 50. Los valores más altos de vulnerabilidad se encuentran en las especies: Rabihorcado Magno (Fregata magnificens), el Zopilote Negro (Coragyps atratus), el Zopilote Cabecirroja (Cathartes aura), Águila Pescadora (Pandion haliaetus), Caracara Crestado (Caracara cheriway), Zanate Nicaragüense (Quiscalus nicaraguensis), y la Garza Grande (Ardea herodias). El bosque ripario y pastizales con árboles son los sitios con mayor riesgo de colisión para instalar torres eólicas. El IVA y MVP constituyen herramientas importantes que permiten identificar los riesgos potenciales de colisión de aves en centrales eólicas antes de su construcción.
Mostrar más [+] Menos [-]Evaluation of the productive behavior of four tomato hybrids, under protected conditions, located in the Chagüite Grande community, department of Jinotega, Nicaragua | Evaluación del comportamiento productivo de cuatro híbridos de tomate, bajo condiciones protegidas, ubicado en la comunidad Chagüite Grande, departamento de Jinotega, Nicaragua Texto completo
2021
Lacayo Barrios, Rosa Isabel | López Mercado, Lesly Junieth | Zamora Mayorga, Sury Aylem | Padilla Duarte, Emilseth Carolina
In Nicaragua, the tomato crop (Solanum Lycopersicum L.) occupies the first place among the vegetables with the highest production and consumption. In the present study, four hybrids were evaluated, three from South Korea and a commercial variety, the experiment was established under a protected agriculture system in a farm of a producer from the community of Chagüite Grande, located in the department of Jinotega in the First cycle 2019. The experimental design implemented was Complete Random Block (BCA) with four repetitions and four treatments. The yield was estimated by means of the longitudinal repeated means methodology and mean separations through the Tukey test (α = 0.05), in the same way phenotypic correlations were made between the yield components. The analyzes were carried out in the R program version 4.0.2 (2020-06-22) through one of its platforms Rbio version 141 (09-20-2020), the physical and chemical analysis of the soil was followed by the methodologies of the laboratories of the National Agrarian University and the University of Engineering. According to the results, the hybrids that presented the best performance were Tisey and Miranda with average yields of 109,728 kg ha-1 and 104,695.9 kg ha-1 respectively, in the same way positive correlations 0.97 are shown for the variables number of commercial fruits and the yield, also the soil presented good physical and chemical properties for good development of the crop. | En Nicaragua el cultivo del tomate (Solanum Lycopersicum L.) ocupa el primer lugar entre las hortalizas de mayor producción y consumo. En el presente estudio se evaluaron cuatro híbridos, tres procedentes de Corea del Sur y un material comercial, el experimento se estableció bajo sistema de agricultura protegida en una finca de un productor de la comunidad de chagüite grande, ubicada en el departamento de Jinotega en el ciclo de Primera 2019. El diseño experimental implementado fue Bloque Completo al Azar (BCA) con cuatro repeticiones y cuatro tratamientos. El rendimiento fue estimado mediante la metodología medias repetidas longitudinales y separaciones de medias a través de prueba de Tukey (α=0.05), de igual manera se realizaron correlaciones fenotípicas entre los componentes de rendimientos. Los análisis fueron realizados en el programa R versión 4.0.2 (2020-06-22) a través de una de sus plataformas Rbio versión 141 (20-09-2020), el análisis físico y químico del suelo se realizaron seguimiento las metodologías de los laboratorios de las Universidad Nacional Agraria y la Universidad de Ingeniería. Según los resultados los híbridos que presentaron mejor comportamiento fueron Tisey y Miranda con rendimiento promedios de 109,728 kg ha-1 y 104,695.9 kg ha-1 respectivamente, de igual manera se muestran correlaciones positivas 0.97 para las variables número de frutos comerciales y el rendimiento, asimismo el suelo presento buenas propiedades física y química para buen desarrollo del cultivo.
Mostrar más [+] Menos [-]Characterization of the drying operation of nancite (byrsonima crassifolia) | Caracterización de la operación de secado de nancite (byrsonima crassifolia) Texto completo
2021
Ruiz Saldívar, Daniela Magaly | Blandón Navarro , Sandra Lorena
Nancite (Byrsonima crassifolia) is a perishable tropical fruit and its harvest period occurs at the beginning of winter (month of May) in the countries of Central America. The fruits are usually consumed raw, in soft drinks, jellies, syrups or jams, as a flavoring for ice cream and as a raw material for artisanal food. However, it is necessary to continue promoting more value-added alternatives for this product. In this sense, previous studies suggest that fresh nancite pulp contributes 66 kcal per 100 grams and has a dry matter content between 20 and 25 %, which can be used in its agro-industrialization as a dehydrated product. Therefore, in this research, the nancite pulp drying process was studied in terms of the impact of temperature on the drying rates and on the color of the final product. Through the proximal analysis of the edible part of the nancite (pulp) a moisture content of 78.80 ± 0.32% (on a wet basis) was determined and on a dry basis a carbohydrate content of 78.67 ± 0.53 and an ether extract of 16.60 ± 0.27% were determined. The drying experiments of this material were carried out in a tunnel dryer using dry air with a speed of 2 m/s at temperatures of 60 °C, 70 °C and 80 °C. The results suggest that moisture content and drying time decrease as the operating temperature increases, however, at 60 °C the dry product presents the least browning, so this drying temperature could be recommended in processes in which that a pale yellow dry pulp is required. | El nancite (Byrsonima crassifolia) es una fruta tropical perecedera, cuyo periodo de cosecha se da al inicio del invierno (mes de mayo) en los países de América Central. Los frutos se suelen consumir crudos, en refrescos, jaleas, jarabes o mermeladas, como saborizante para helados y como materia prima para productos de elaboración artesanal. No obstante, es necesario continuar promoviendo más alternativas de valor agregado para dicho producto. En ese sentido, estudios previos sugieren que la pulpa de nancite fresca aporta 66 kcal por cada 100 gramos y presenta un contenido de materia seca entre 20 y 25 %, lo que puede ser aprovechado en su agroindustrialización como producto deshidratado. Por lo tanto, en esta investigación se estudió el proceso de secado de la pulpa de nancite en términos del impacto de la temperatura en las tasas de secado y en el color del producto final. A través del análisis proximal de la parte comestible del nancite (pulpa) se determinó un contenido de humedad de 78.80 ± 0.32 % (b.h) y en base seca se determinó un contenido de carbohidratos de 78.67 ± 0.53 y extracto etéreo de 16.60 ± 0.27 %. Los experimentos de secado de este material se realizaron en secador de túnel usando aire seco con una velocidad de 2 m/s a temperaturas de 60°C, 70°C y 80°C. Los resultados sugieren que el contenido de humedad y el tiempo de secado disminuyen conforme se incrementa la temperatura de operación, sin embargo, a 60°C el producto seco presenta el menor pardeamiento, por lo que esta temperatura de secado podría recomendarse en procesos en los que se requiera una pulpa seca de color amarillo pálido.
Mostrar más [+] Menos [-]Gap-filling eddy covariance methane fluxes: Comparison of machine learning model predictions and uncertainties at FLUXNET-CH4 wetlands Texto completo
2021
Irvin, Jeremy | Zhou, Sharon | McNicol, Gavin | Lu, Fred | Liu, Vincent | Fluet-Chouinard, Etienne | Ouyang, Zutao | Knox, Sara Helen | Lucas-Moffat, Antje | Trotta, Carlo | Papale, Dario | Vitale, Domenico | Mammarella, Ivan | Alekseychik, Pavel | Aurela, Mika | Avati, Anand | Baldocchi, Dennis | Bansal, Sheel | Bohrer, Gil | Campbell, David I. | Jiquan Chen | Chu, Housen | Dalmagro, Higo J. | Delwiche, Kyle B. | Desai, Ankur R. | Euskirchen, Eugénie | Feron, Sarah | Goeckede, Mathias | Heimann, Martin | Helbig, Manuel | Helfter, Carole | Hemes, Kyle S. | Hirano, Takashi | Iwata, Hiroki | Jurasinski, Gerald | Kalhori, Aram | Kondrich, Andrew | Lai, Derrick Y.F. | Lohila, Annalea | Malhotra, Avni | Merbold, Lutz | Mitra, Bhaskar | Ng, Andrew | Nilsson, Mats B. | Noormets, Asko | Peichl, Matthias | Rey Sanchez, A. Camilo | Richardson, Andrew D. | Runkle, Benjamin R.K. | Schäfer, Karina V.R. | Sonnentag, Oliver | Stuart-Haëntjens, Ellen | Sturtevant, Cove | Ueyama, Masahito | Valach, Alex C. | Vargas, Rodrigo | Vourlitis, George L. | Ward, Eric J. | Wong, Guan Xhuan | Zona, Donatella | Alberto, Ma.Carmelita R. | Billesbach, David P. | Celis, Gerardo | Dolman, Han | Friborg, Thomas | Fuchs, Kathrin | Gogo, Sébastien | Gondwe, Mangaliso J. | Goodrich, Jordan P. | Gottschalk, Pia | Hörtnagl, Lukas | Jacotot, Adrien | Koebsch, Franziska | Kasak, Kuno | Maier, Regine | Morin, Timothy H. | Nemitz, Eiko | Oechel, Walter C. | Oikawa, Patricia Y. | Ono, Keisuke | Sachs, Torsten | Sakabe, Ayaka | Schuur, Edward A.G. | Shortt, Robert | Sullivan, Ryan C. | Szutu, Daphne J. | Tuittila, Eeva-Stiina | Varlagin, Andrej | Verfaillie, Joseph G. | Wille, Christian | Windham-Myers, Lisamarie | Poulter, Benjamin | Jackson, Robert B.
Gap-filling eddy covariance methane fluxes: Comparison of machine learning model predictions and uncertainties at FLUXNET-CH4 wetlands Texto completo
2021
Irvin, Jeremy | Zhou, Sharon | McNicol, Gavin | Lu, Fred | Liu, Vincent | Fluet-Chouinard, Etienne | Ouyang, Zutao | Knox, Sara Helen | Lucas-Moffat, Antje | Trotta, Carlo | Papale, Dario | Vitale, Domenico | Mammarella, Ivan | Alekseychik, Pavel | Aurela, Mika | Avati, Anand | Baldocchi, Dennis | Bansal, Sheel | Bohrer, Gil | Campbell, David I. | Jiquan Chen | Chu, Housen | Dalmagro, Higo J. | Delwiche, Kyle B. | Desai, Ankur R. | Euskirchen, Eugénie | Feron, Sarah | Goeckede, Mathias | Heimann, Martin | Helbig, Manuel | Helfter, Carole | Hemes, Kyle S. | Hirano, Takashi | Iwata, Hiroki | Jurasinski, Gerald | Kalhori, Aram | Kondrich, Andrew | Lai, Derrick Y.F. | Lohila, Annalea | Malhotra, Avni | Merbold, Lutz | Mitra, Bhaskar | Ng, Andrew | Nilsson, Mats B. | Noormets, Asko | Peichl, Matthias | Rey Sanchez, A. Camilo | Richardson, Andrew D. | Runkle, Benjamin R.K. | Schäfer, Karina V.R. | Sonnentag, Oliver | Stuart-Haëntjens, Ellen | Sturtevant, Cove | Ueyama, Masahito | Valach, Alex C. | Vargas, Rodrigo | Vourlitis, George L. | Ward, Eric J. | Wong, Guan Xhuan | Zona, Donatella | Alberto, Ma.Carmelita R. | Billesbach, David P. | Celis, Gerardo | Dolman, Han | Friborg, Thomas | Fuchs, Kathrin | Gogo, Sébastien | Gondwe, Mangaliso J. | Goodrich, Jordan P. | Gottschalk, Pia | Hörtnagl, Lukas | Jacotot, Adrien | Koebsch, Franziska | Kasak, Kuno | Maier, Regine | Morin, Timothy H. | Nemitz, Eiko | Oechel, Walter C. | Oikawa, Patricia Y. | Ono, Keisuke | Sachs, Torsten | Sakabe, Ayaka | Schuur, Edward A.G. | Shortt, Robert | Sullivan, Ryan C. | Szutu, Daphne J. | Tuittila, Eeva-Stiina | Varlagin, Andrej | Verfaillie, Joseph G. | Wille, Christian | Windham-Myers, Lisamarie | Poulter, Benjamin | Jackson, Robert B.
Gap-filling eddy covariance methane fluxes: Comparison of machine learning model predictions and uncertainties at FLUXNET-CH4 wetlands Texto completo
2021
Irvin, Jeremy | Zhou, Sharon | McNicol, Gavin | Lu, Fred | Liu, Vincent | Fluet-Chouinard, Etienne | Ouyang, Zutao | Knox, Sara Helen | Lucas-Moffat, Antje | Trotta, Carlo | Papale, Dario | Vitale, Domenico | Mammarella, Ivan | Alekseychik, Pavel | Aurela, Mika | Avati, Anand | Baldocchi, Dennis | Bansal, Sheel | Bohrer, Gil | Campbell, David I | Chen, Jiquan | Chu, Housen | Dalmagro, Higo J | Delwiche, Kyle B | Desai, Ankur R | Euskirchen, Eugenie | Feron, Sarah | Goeckede, Mathias | Heimann, Martin | Helbig, Manuel | Helfter, Carole | Hemes, Kyle S | Hirano, Takashi | Iwata, Hiroki | Jurasinski, Gerald | Kalhori, Aram | Kondrich, Andrew | Lai, Derrick YF | Lohila, Annalea | Malhotra, Avni | Merbold, Lutz | Mitra, Bhaskar | Ng, Andrew | Nilsson, Mats B | Noormets, Asko | Peichl, Matthias | Rey-Sanchez, A. Camilo | Richardson, Andrew D | Runkle, Benjamin RK | Schäfer, Karina VR | Sonnentag, Oliver | Stuart-Haëntjens, Ellen | Sturtevant, Cove | Ueyama, Masahito | Valach, Alex C | Vargas, Rodrigo | Vourlitis, George L | Ward, Eric J | Wong, Guan Xhuan | Zona, Donatella | Alberto, Ma. Carmelita R | Billesbach, David P | Celis, Gerardo | Dolman, Han | Friborg, Thomas | Fuchs, Kathrin | Gogo, Sébastien | Gondwe, Mangaliso J | Goodrich, Jordan P | Gottschalk, Pia | Hörtnagl, Lukas | Jacotot, Adrien | Koebsch, Franziska | Kasak, Kuno | Maier, Regine | Morin, Timothy H | Nemitz, Eiko | Oechel, Walter C | Oikawa, Patricia Y | Ono, Keisuke | Sachs, Torsten | Sakabe, Ayaka | Schuur, Edward A | Shortt, Robert | Sullivan, Ryan C | Szutu, Daphne J | Tuittila, Eeva-Stiina | Varlagin, Andrej | Verfaillie, Joeseph G | Wille, Christian | Windham-Myers, Lisamarie | Poulter, Benjamin | Jackson, Robert B | https://orcid.org/0000-0002-4081-3917 | 4100311110 | Luonnonvarakeskus
Gap-filling eddy covariance methane fluxes: Comparison of machine learning model predictions and uncertainties at FLUXNET-CH4 wetlands Texto completo
2021
Irvin, Jeremy | Zhou, Sharon | McNicol, Gavin | Lu, Fred | Liu, Vincent | Fluet-Chouinard, Etienne | Ouyang, Zutao | Knox, Sara Helen | Lucas-Moffat, Antje | Trotta, Carlo | Papale, Dario | Vitale, Domenico | Mammarella, Ivan | Alekseychik, Pavel | Aurela, Mika | Avati, Anand | Baldocchi, Dennis | Bansal, Sheel | Bohrer, Gil | Campbell, David I | Chen, Jiquan | Chu, Housen | Dalmagro, Higo J | Delwiche, Kyle B | Desai, Ankur R | Euskirchen, Eugenie | Feron, Sarah | Goeckede, Mathias | Heimann, Martin | Helbig, Manuel | Helfter, Carole | Hemes, Kyle S | Hirano, Takashi | Iwata, Hiroki | Jurasinski, Gerald | Kalhori, Aram | Kondrich, Andrew | Lai, Derrick YF | Lohila, Annalea | Malhotra, Avni | Merbold, Lutz | Mitra, Bhaskar | Ng, Andrew | Nilsson, Mats B | Noormets, Asko | Peichl, Matthias | Rey-Sanchez, A Camilo | Richardson, Andrew D. | Runkle, Benjamin RK | Schäfer, Karina VR | Sonnentag, Oliver | Stuart-Haëntjens, Ellen | Sturtevant, Cove | Ueyama, Masahito | Valach, Alex C | Vargas, Rodrigo | Vourlitis, George L | Ward, Eric J | Wong, Guan Xhuan | Zona, Donatella | Alberto, Ma Carmelita R | Billesbach, David P. | Celis, Gerardo | Dolman, A. J. | Friborg, Thomas | Fuchs, Kathrin | Gogo, Sébastien | Gondwe, Mangaliso J | Goodrich, Jordan P | Gottschalk, Pia | Hörtnagl, Lukas | Jacotot, Adrien | Koebsch, Franziska | Kasak, Kuno | Maier, Regine | Morin, Timothy H | Nemitz, Eiko | Oechel, Walter C | Oikawa, Patricia Y | Ono, Keisuke | Sachs, Torsten | Sakabe, Ayaka | Schuur, Edward A | Shortt, Robert | Sullivan, Ryan C | Szutu, Daphne J | Tuittila, Eeva-Stiina | Varlagin, Andrej | Verfaillie, Joeseph G | Wille, Christian | Windham-Myers, Lisamarie | Poulter, Benjamin | Jackson, Robert B.
Time series of wetland methane fluxes measured by eddy covariance require gap-filling to estimate daily, seasonal, and annual emissions. Gap-filling methane fluxes is challenging because of high variability and complex responses to multiple drivers. To date, there is no widely established gap-filling standard for wetland methane fluxes, with regards both to the best model algorithms and predictors. This study synthesizes results of different gap-filling methods systematically applied at 17 wetland sites spanning boreal to tropical regions and including all major wetland classes and two rice paddies. Procedures are proposed for: 1) creating realistic artificial gap scenarios, 2) training and evaluating gap-filling models without overstating performance, and 3) predicting half-hourly methane fluxes and annual emissions with realistic uncertainty estimates. Performance is compared between a conventional method (marginal distribution sampling) and four machine learning algorithms. The conventional method achieved similar median performance as the machine learning models but was worse than the best machine learning models and relatively insensitive to predictor choices. Of the machine learning models, decision tree algorithms performed the best in cross-validation experiments, even with a baseline predictor set, and artificial neural networks showed comparable performance when using all predictors. Soil temperature was frequently the most important predictor whilst water table depth was important at sites with substantial water table fluctuations, highlighting the value of data on wetland soil conditions. Raw gap-filling uncertainties from the machine learning models were underestimated and we propose a method to calibrate uncertainties to observations. The python code for model development, evaluation, and uncertainty estimation is publicly available. This study outlines a modular and robust machine learning workflow and makes recommendations for, and evaluates an improved baseline of, methane gap-filling models that can be implemented in multi-site syntheses or standardized products from regional and global flux networks (e.g., FLUXNET).
Mostrar más [+] Menos [-]FLUXNET-CH4: a global, multi-ecosystem dataset and analysis of methane seasonality from freshwater wetlands Texto completo
2021
Delwiche, Kyle B. | Knox, Sara Helen | Malhotra, Avni | Fluet-Chouinard, Etienne | McNicol, Gavin | Feron, Sarah | Ouyang, Zutao | Papale, Dario | Trotta, Carlo | Canfora, Eleonora | Cheah, You-Wei | Christianson, Danielle | Alberto, Ma.Carmelita R. | Alekseychik, Pavel | Aurela, Mika | Baldocchi, Dennis | Bansal, Sheel | Billesbach, David P. | Bohrer, Gil | Bracho, Rosvel | Buchmann, Nina | Campbell, David I. | Celis, Gerardo | Jiquan Chen | Weinan Chen | Chu, Housen | Dalmagro, Higo J. | Dengel, Sigrid | Desai, Ankur R. | Detto, Matteo | Dolman, Han | Eichelmann, Elke | Euskirchen, Eugénie | Famulari, Daniela | Fuchs, Kathrin | Goeckede, Mathias | Gogo, Sébastien | Gondwe, Mangaliso J. | Goodrich, Jordan P. | Gottschalk, Pia | Graham, Scott L. | Heimann, Martin | Helbig, Manuel | Helfter, Carole | Hemes, Kyle S. | Hirano, Takashi | Hollinger, David | Hörtnagl, Lukas | Iwata, Hiroki | Jacotot, Adrien | Jurasinski, Gerald | Kang, Minseok | Kasak, Kuno | King, John | Klatt, Janina | Koebsch, Franziska | Krauss, Ken W. | Lai, Derrick Y.F. | Lohila, Annalea | Mammarella, Ivan | Belelli Marchesini, Luca | Manca, Giovanni | Matthes, Jaclyn Hatala | Maximov, Trofim | Merbold, Lutz | Mitra, Bhaskar | Morin, Timothy H. | Nemitz, Eiko | Nilsson, Mats B. | Niu, Shuli | Oechel, Walter C. | Oikawa, Patricia Y. | Ono, Keisuke | Peichl, Matthias | Peltola, Olli | Reba, Michele L. | Richardson, Andrew D. | Riley, William | Runkle, Benjamin R.K. | Ryu, Youngryel | Sachs, Torsten | Sakabe, Ayaka | Sanchez, Camilo Rey | Schuur, Edward A.G. | Schäfer, Karina V.R. | Sonnentag, Oliver | Sparks, Jed P. | Stuart-Haëntjens, Ellen | Sturtevant, Cove | Sullivan, Ryan C. | Szutu, Daphne J. | Thom, Jonathan E. | Torn, Margaret S. | Tuittila, Eeva-Stiina | Turner, Jessica | Ueyama, Masahito | Valach, Alex C. | Vargas, Rodrigo | Varlagin, Andrej | Vazquez-Lule, Alma | Verfaillie, Joseph G. | Vesala, Timo | Vourlitis, George L. | Ward, Eric J. | Wille, Christian | Wohlfahrt, Georg | Wong, Guan Xhuan | Zhang, Zhen | Zona, Donatella | Windham-Myers, Lisamarie | Poulter, Benjamin | Jackson, Robert B.
FLUXNET-CH4: a global, multi-ecosystem dataset and analysis of methane seasonality from freshwater wetlands Texto completo
2021
Delwiche, Kyle B. | Knox, Sara Helen | Malhotra, Avni | Fluet-Chouinard, Etienne | McNicol, Gavin | Feron, Sarah | Ouyang, Zutao | Papale, Dario | Trotta, Carlo | Canfora, Eleonora | Cheah, You-Wei | Christianson, Danielle | Alberto, Ma.Carmelita R. | Alekseychik, Pavel | Aurela, Mika | Baldocchi, Dennis | Bansal, Sheel | Billesbach, David P. | Bohrer, Gil | Bracho, Rosvel | Buchmann, Nina | Campbell, David I. | Celis, Gerardo | Jiquan Chen | Weinan Chen | Chu, Housen | Dalmagro, Higo J. | Dengel, Sigrid | Desai, Ankur R. | Detto, Matteo | Dolman, Han | Eichelmann, Elke | Euskirchen, Eugénie | Famulari, Daniela | Fuchs, Kathrin | Goeckede, Mathias | Gogo, Sébastien | Gondwe, Mangaliso J. | Goodrich, Jordan P. | Gottschalk, Pia | Graham, Scott L. | Heimann, Martin | Helbig, Manuel | Helfter, Carole | Hemes, Kyle S. | Hirano, Takashi | Hollinger, David | Hörtnagl, Lukas | Iwata, Hiroki | Jacotot, Adrien | Jurasinski, Gerald | Kang, Minseok | Kasak, Kuno | King, John | Klatt, Janina | Koebsch, Franziska | Krauss, Ken W. | Lai, Derrick Y.F. | Lohila, Annalea | Mammarella, Ivan | Belelli Marchesini, Luca | Manca, Giovanni | Matthes, Jaclyn Hatala | Maximov, Trofim | Merbold, Lutz | Mitra, Bhaskar | Morin, Timothy H. | Nemitz, Eiko | Nilsson, Mats B. | Niu, Shuli | Oechel, Walter C. | Oikawa, Patricia Y. | Ono, Keisuke | Peichl, Matthias | Peltola, Olli | Reba, Michele L. | Richardson, Andrew D. | Riley, William | Runkle, Benjamin R.K. | Ryu, Youngryel | Sachs, Torsten | Sakabe, Ayaka | Sanchez, Camilo Rey | Schuur, Edward A.G. | Schäfer, Karina V.R. | Sonnentag, Oliver | Sparks, Jed P. | Stuart-Haëntjens, Ellen | Sturtevant, Cove | Sullivan, Ryan C. | Szutu, Daphne J. | Thom, Jonathan E. | Torn, Margaret S. | Tuittila, Eeva-Stiina | Turner, Jessica | Ueyama, Masahito | Valach, Alex C. | Vargas, Rodrigo | Varlagin, Andrej | Vazquez-Lule, Alma | Verfaillie, Joseph G. | Vesala, Timo | Vourlitis, George L. | Ward, Eric J. | Wille, Christian | Wohlfahrt, Georg | Wong, Guan Xhuan | Zhang, Zhen | Zona, Donatella | Windham-Myers, Lisamarie | Poulter, Benjamin | Jackson, Robert B.
Abstract. Methane (CH4) emissions from natural landscapes constitute roughly half of global CH4 contributions to the atmosphere, yet large uncertainties remain in the absolute magnitude and the seasonality of emission quantities and drivers. Eddy covariance (EC) measurements of CH4 flux are ideal for constraining ecosystem-scale CH4 emissions due to quasi-continuous and high-temporal-resolution CH4 flux measurements, coincident carbon dioxide, water, and energy flux measurements, lack of ecosystem disturbance, and increased availability of datasets over the last decade. Here, we (1) describe the newly published dataset, FLUXNET-CH4 Version 1.0, the first open-source global dataset of CH4 EC measurements (available at https://fluxnet.org/data/fluxnet-ch4-community-product/, last access: 7 April 2021). FLUXNET-CH4 includes half-hourly and daily gap-filled and non-gap-filled aggregated CH4 fluxes and meteorological data from 79 sites globally: 42 freshwater wetlands, 6 brackish and saline wetlands, 7 formerly drained ecosystems, 7 rice paddy sites, 2 lakes, and 15 uplands. Then, we (2) evaluate FLUXNET-CH4 representativeness for freshwater wetland coverage globally because the majority of sites in FLUXNET-CH4 Version 1.0 are freshwater wetlands which are a substantial source of total atmospheric CH4 emissions; and (3) we provide the first global estimates of the seasonal variability and seasonality predictors of freshwater wetland CH4 fluxes. Our representativeness analysis suggests that the freshwater wetland sites in the dataset cover global wetland bioclimatic attributes (encompassing energy, moisture, and vegetation-related parameters) in arctic, boreal, and temperate regions but only sparsely cover humid tropical regions. Seasonality metrics of wetland CH4 emissions vary considerably across latitudinal bands. In freshwater wetlands (except those between 20∘ S to 20∘ N) the spring onset of elevated CH4 emissions starts 3 d earlier, and the CH4 emission season lasts 4 d longer, for each degree Celsius increase in mean annual air temperature. On average, the spring onset of increasing CH4 emissions lags behind soil warming by 1 month, with very few sites experiencing increased CH4 emissions prior to the onset of soil warming. In contrast, roughly half of these sites experience the spring onset of rising CH4 emissions prior to the spring increase in gross primary productivity (GPP). The timing of peak summer CH4 emissions does not correlate with the timing for either peak summer temperature or peak GPP. Our results provide seasonality parameters for CH4 modeling and highlight seasonality metrics that cannot be predicted by temperature or GPP (i.e., seasonality of CH4 peak). FLUXNET-CH4 is a powerful new resource for diagnosing and understanding the role of terrestrial ecosystems and climate drivers in the global CH4 cycle, and future additions of sites in tropical ecosystems and site years of data collection will provide added value to this database. All seasonality parameters are available at https://doi.org/10.5281/zenodo.4672601 (Delwiche et al., 2021). Additionally, raw FLUXNET-CH4 data used to extract seasonality parameters can be downloaded from https://fluxnet.org/data/fluxnet-ch4-community-product/ (last access: 7 April 2021), and a complete list of the 79 individual site data DOIs is provided in Table 2 of this paper.
Mostrar más [+] Menos [-]FLUXNET-CH4: a global, multi-ecosystem dataset and analysis of methane seasonality from freshwater wetlands Texto completo
2021
Delwiche, Kyle B. | Knox, Sara Helen | Malhotra, Avni | Fluet-Chouinard, Etienne | McNicol, Gavin | Feron, Sarah | Ouyang, Zutao | Papale, Dario | Trotta, Carlo | Canfora, Eleonora | Cheah, You-Wei | Christianson, Danielle | Alberto, Ma. Carmelita R. | Alekseychik, Pavel | Aurela, Mika | Baldocchi, Dennis | Bansal, Sheel | Billesbach, David P. | Bohrer, Gil | Bracho, Rosvel | Buchmann, Nina | Campbell, David I. | Celis, Gerardo | Chen, Jiquan | Chen, Weinan | Chu, Housen | Dalmagro, Higo J. | Dengel, Sigrid | Desai, Ankur R. | Detto, Matteo | Dolman, Han | Eichelmann, Elke | Euskirchen, Eugenie | Famulari, Daniela | Fuchs, Kathrin | Goeckede, Mathias | Gogo, Sébastien | Gondwe, Mangaliso J. | Goodrich, Jordan P. | Gottschalk, Pia | Graham, Scott L. | Heimann, Martin | Helbig, Manuel | Helfter, Carole | Hemes, Kyle S. | Hirano, Takashi | Hollinger, David | Hörtnagl, Lukas | Iwata, Hiroki | Jacotot, Adrien | Jurasinski, Gerald | Kang, Minseok | Kasak, Kuno | King, John | Klatt, Janina | Koebsch, Franziska | Krauss, Ken W. | Lai, Derrick Y. F. | Lohila, Annalea | Mammarella, Ivan | Belelli Marchesini, Luca | Manca, Giovanni | Matthes, Jaclyn Hatala | Maximov, Trofim | Merbold, Lutz | Mitra, Bhaskar | Morin, Timothy H. | Nemitz, Eiko | Nilsson, Mats B. | Niu, Shuli | Oechel, Walter C. | Oikawa, Patricia Y. | Ono, Keisuke | Peichl, Matthias | Peltola, Olli | Reba, Michele L. | Richardson, Andrew D. | Riley, William | Runkle, Benjamin R. K. | Ryu, Youngryel | Sachs, Torsten | Sakabe, Ayaka | Sanchez, Camilo Rey | Schuur, Edward A. | Schäfer, Karina V. R. | Sonnentag, Oliver | Sparks, Jed P. | Stuart-Haëntjens, Ellen | Sturtevant, Cove | Sullivan, Ryan C. | Szutu, Daphne J. | Thom, Jonathan E. | Torn, Margaret S. | Tuittila, Eeva-Stiina | Turner, Jessica | Ueyama, Masahito | Valach, Alex C. | Vargas, Rodrigo | Varlagin, Andrej | Vazquez-Lule, Alma | Verfaillie, Joseph G. | Vesala, Timo | Vourlitis, George L. | Ward, Eric J. | Wille, Christian | Wohlfahrt, Georg | Wong, Guan Xhuan | Zhang, Zhen | Zona, Donatella | Windham-Myers, Lisamarie | Poulter, Benjamin | Jackson, Robert B. | https://orcid.org/0000-0002-4081-3917 | 4100311110 | Luonnonvarakeskus
Methane (CH4) emissions from natural landscapes constitute roughly half of global CH4 contributions to the atmosphere, yet large uncertainties remain in the absolute magnitude and the seasonality of emission quantities and drivers. Eddy covariance (EC) measurements of CH4 flux are ideal for constraining ecosystem-scale CH4 emissions due to quasi-continuous and high-temporal-resolution CH4 flux measurements, coincident carbon dioxide, water, and energy flux measurements, lack of ecosystem disturbance, and increased availability of datasets over the last decade. Here, we (1) describe the newly published dataset, FLUXNET-CH4 Version 1.0, the first open-source global dataset of CH4 EC measurements (available at https://fluxnet.org/data/fluxnet-ch4-community-product/, last access: 7 April 2021). FLUXNET-CH4 includes half-hourly and daily gap-filled and non-gap-filled aggregated CH4 fluxes and meteorological data from 79 sites globally: 42 freshwater wetlands, 6 brackish and saline wetlands, 7 formerly drained ecosystems, 7 rice paddy sites, 2 lakes, and 15 uplands. Then, we (2) evaluate FLUXNET-CH4 representativeness for freshwater wetland coverage globally because the majority of sites in FLUXNET-CH4 Version 1.0 are freshwater wetlands which are a substantial source of total atmospheric CH4 emissions; and (3) we provide the first global estimates of the seasonal variability and seasonality predictors of freshwater wetland CH4 fluxes. Our representativeness analysis suggests that the freshwater wetland sites in the dataset cover global wetland bioclimatic attributes (encompassing energy, moisture, and vegetation-related parameters) in arctic, boreal, and temperate regions but only sparsely cover humid tropical regions. Seasonality metrics of wetland CH4 emissions vary considerably across latitudinal bands. In freshwater wetlands (except those between 20∘ S to 20∘ N) the spring onset of elevated CH4 emissions starts 3 d earlier, and the CH4 emission season lasts 4 d longer, for each degree Celsius increase in mean annual air temperature. On average, the spring onset of increasing CH4 emissions lags behind soil warming by 1 month, with very few sites experiencing increased CH4 emissions prior to the onset of soil warming. In contrast, roughly half of these sites experience the spring onset of rising CH4 emissions prior to the spring increase in gross primary productivity (GPP). The timing of peak summer CH4 emissions does not correlate with the timing for either peak summer temperature or peak GPP. Our results provide seasonality parameters for CH4 modeling and highlight seasonality metrics that cannot be predicted by temperature or GPP (i.e., seasonality of CH4 peak). FLUXNET-CH4 is a powerful new resource for diagnosing and understanding the role of terrestrial ecosystems and climate drivers in the global CH4 cycle, and future additions of sites in tropical ecosystems and site years of data collection will provide added value to this database. All seasonality parameters are available at https://doi.org/10.5281/zenodo.4672601 (Delwiche et al., 2021). Additionally, raw FLUXNET-CH4 data used to extract seasonality parameters can be downloaded from https://fluxnet.org/data/fluxnet-ch4-community-product/ (last access: 7 April 2021), and a complete list of the 79 individual site data DOIs is provided in Table 2 of this paper. | 2021
Mostrar más [+] Menos [-]FLUXNET-CH4: a global, multi-ecosystem dataset and analysis of methane seasonality from freshwater wetlands Texto completo
2021
Delwiche, Kyle B. | Knox, Sara Helen | Malhotra, Avni | Fluet-Chouinard, Etienne | McNicol, Gavin | Feron, Sarah | Ouyang, Zutao | Papale, Dario | Trotta, Carlo | Canfora, Eleonora | Cheah, You-Wei | Christianson, Danielle | Alberto, Ma Carmelita R. | Alekseychik, Pavel | Aurela, Mika | Baldocchi, Dennis | Bansal, Sheel | Billesbach, David P. | Bohrer, Gil | Bracho, Rosvel | Buchmann, Nina | Campbell, David I. | Celis, Gerardo | Chen, Jiquan | Chen, Weinan | Chu, Housen | Dalmagro, Higo J. | Dengel, Sigrid | Desai, Ankur R. | Detto, Matteo | Dolman, Han | Eichelmann, Elke | Euskirchen, Eugenie | Famulari, Daniela | Fuchs, Kathrin | Goeckede, Mathias | Gogo, Sebastien | Gondwe, Mangaliso J. | Goodrich, Jordan P. | Gottschalk, Pia | Graham, Scott L. | Heimann, Martin | Helbig, Manuel | Helfter, Carole | Hemes, Kyle S. | Hirano, Takashi | Hollinger, David | Hortnagl, Lukas | Iwata, Hiroki | Jacotot, Adrien | Jurasinski, Gerald | Kang, Minseok | Kasak, Kuno | King, John | Klatt, Janina | Koebsch, Franziska | Krauss, Ken W. | Lai, Derrick Y. F. | Lohila, Annalea | Mammarella, Ivan | Marchesini, Luca Belelli | Manca, Giovanni | Matthes, Jaclyn Hatala | Maximov, Trofim | Merbold, Lutz | Mitra, Bhaskar | Morin, Timothy H. | Nemitz, Eiko | Nilsson, Mats | Niu, Shuli | Oechel, Walter C. | Oikawa, Patricia Y. | Ono, Keisuke | Peichl, Matthias | Peltola, Olli | Reba, Michele L. | Richardson, Andrew D. | Riley, William | Runkle, Benjamin R. K. | Ryu, Youngryel | Sachs, Torsten | Sakabe, Ayaka | Sanchez, Camilo Rey | Schuur, Edward A. | Schäfer, Karina V. R. | Sonnentag, Oliver | Sparks, Jed P. | Stuart-Haentjens, Ellen | Sturtevant, Cove | Sullivan, Ryan C. | Szutu, Daphne J. | Thom, Jonathan E. | Torn, Margaret S. | Tuittila, Eeva-Stiina | Turner, Jessica | Ueyama, Masahito | Valach, Alex C. | Vargas, Rodrigo | Varlagin, Andrej | Vazquez-Lule, Alma | Verfaillie, Joseph G. | Vesala, Timo | Vourlitis, George L. | Ward, Eric J. | Wille, Christian | Wohlfahrt, Georg | Wong, Guan Xhuan | Zhang, Zhen | Zona, Donatella | Windham-Myers, Lisamarie | Poulter, Benjamin | Jackson, Robert B.
Methane (CH4) emissions from natural landscapes constitute roughly half of global CH4 contributions to the atmosphere, yet large uncertainties remain in the absolute magnitude and the seasonality of emission quantities and drivers. Eddy covariance (EC) measurements of CH4 flux are ideal for constraining ecosystem-scale CH4 emissions due to quasi-continuous and high-temporal-resolution CH4 flux measurements, coincident carbon dioxide, water, and energy flux measurements, lack of ecosystem disturbance, and increased availability of datasets over the last decade. Here, we (1) describe the newly published dataset, FLUXNET-CH4 Version 1.0, the first open-source global dataset of CH4 EC measurements (available at https://fluxnet.org/data/fluxnet-ch4-community-product/, last access: 7 April 2021). FLUXNET-CH4 includes half-hourly and daily gap-filled and non-gap-filled aggregated CH4 fluxes and meteorological data from 79 sites globally: 42 freshwater wetlands, 6 brackish and saline wetlands, 7 formerly drained ecosystems, 7 rice paddy sites, 2 lakes, and 15 uplands. Then, we (2) evaluate FLUXNET-CH4 representativeness for freshwater wetland coverage globally because the majority of sites in FLUXNET-CH4 Version 1.0 are freshwater wetlands which are a substantial source of total atmospheric CH4 emissions; and (3) we provide the first global estimates of the seasonal variability and seasonality predictors of freshwater wetland CH4 fluxes. Our representativeness analysis suggests that the freshwater wetland sites in the dataset cover global wetland bioclimatic attributes (encompassing energy, moisture, and vegetation-related parameters) in arctic, boreal, and temperate regions but only sparsely cover humid tropical regions. Seasonality metrics of wetland CH4 emissions vary considerably across latitudinal bands. In freshwater wetlands (except those between 20 degrees S to 20 degrees N) the spring onset of elevated CH4 emissions starts 3 d earlier, and the CH4 emission season lasts 4 d longer, for each degree Celsius increase in mean annual air temperature. On average, the spring onset of increasing CH4 emissions lags behind soil warming by 1 month, with very few sites experiencing increased CH4 emissions prior to the onset of soil warming. In contrast, roughly half of these sites experience the spring onset of rising CH4 emissions prior to the spring increase in gross primary productivity (GPP). The timing of peak summer CH4 emissions does not correlate with the timing for either peak summer temperature or peak GPP. Our results provide seasonality parameters for CH4 modeling and highlight seasonality metrics that cannot be predicted by temperature or GPP (i.e., seasonality of CH4 peak). FLUXNET-CH4 is a powerful new resource for diagnosing and understanding the role of terrestrial ecosystems and climate drivers in the global CH4 cycle, and future additions of sites in tropical ecosystems and site years of data collection will provide added value to this database. All seasonality parameters are available at https://doi.org/10.5281/zenodo.4672601 (Delwiche et al., 2021). Additionally, raw FLUXNET-CH4 data used to extract seasonality parameters can be downloaded from https://fluxnet.org/data/fluxnet-ch4-community-product/ (last access: 7 April 2021), and a complete list of the 79 individual site data DOIs is provided in Table 2 of this paper.
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