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1.
Artigo em Inglês | MEDLINE | ID: mdl-32615065

RESUMO

Sugarcane cultivation requires correct fertilizer rates. However, when nutrients are not available, or there is over-fertilization, the yields are significantly reduced and the environmental burden increase. In this study, it is proposed a decision support system (DSS) for the correct NPK (nitrogen, phosphorus and potassium) fertilization. The DSS consists of two fuzzy models; the edaphic condition model (EDC-M) and the NPK fertilization model (NPK-M). The DSS using parameters from soil analysis and is based on the experience of two groups of experts to avoid the bias to the reality of a single group of professionals. The results of the DSS are compared with the results of soil analysis and those of the group of experts. One hundred and sixty tests were developed in the NPK-M. The N rate shows R 2=0.981 for the DSS and R 2=0.963 for soil analyzes. The P rate shows R 2=0.9702 for the DSS and R 2=0.9183 for the soil analyzes. The K rate shows R 2=0.9691 for the DSS and R 2=0.9663 for the soil analyzes. Environmental results indicate that the estimated rates with the DSS do reduce the environmental impact on the tests performed.


Assuntos
Agricultura/métodos , Técnicas de Apoio para a Decisão , Fertilizantes/efeitos adversos , Saccharum/crescimento & desenvolvimento , Mudança Climática , Ecossistema , Fertilizantes/análise , Humanos , Nitrogênio/efeitos adversos , Nitrogênio/análise , Fósforo/efeitos adversos , Fósforo/análise , Potássio/efeitos adversos , Potássio/análise , Medição de Risco , Solo/química
2.
Rev. biol. trop ; Rev. biol. trop;67(4)sept. 2019.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1507559

RESUMO

El noroeste de México alberga las mayores abundancias de aves playeras del país. Sin embargo, para muchos de estos humedales, información sobre comunidades de aves playeras, como abundancia, tendencias poblacionales y riqueza es limitada. Actualmente, los sitios de descanso son críticos para la conservación porque las poblaciones de aves playeras han decaído en las últimas décadas. Marismas Nacionales (MN) es un humedal tropical importante con un ecosistema dinámico donde los estudios de aves playeras están limitados a unos pocos censos aéreos y terrestres. Así el objetivo del trabajo fue describir la abundancia y distribución espacial y temporal de las aves playeras en MN (temporada 2010-2011). Se seleccionaron ocho unidades de muestreo en las que se llevaron a cabo censos mensuales (noviembre 2010 a junio 2011). Se determinaron las riquezas y abundancias por sitio-mes, además se realizó un análisis espacial y temporal de las especies dominantes. Se registraron 27 especies de aves playeras y un género, con un estimado mínimo de 136 236 individuos. Este número hace a MN uno de los humedales prioritarios para la conservación en México, pues alberga al 10 % de la abundancia general del noroeste. Las especies dominantes fueron el Playerito occidental (Calidris mauri, 33 % del total), la Avoceta americana (Recurvirostra americana, 31 %) y los Costureros (Limnodromus spp., 17 %). Espacialmente las lagunas de mayor importancia fueron: Chumbeño (37 % del total registrado), Las Garzas-Chahuin (24 %) y La Polca (24 %). Este trabajo actualiza la información sobre aves playeras que utilizan MN y podría permitir el establecimiento de un programa de monitoreo, lo cual es prioritario sobre todo porque el área es un Sitio de Importancia Internacional por parte de la Red Hemisférica de Reserva para las Aves Playeras.


Northwest Mexico is an important region for shorebirds associated with an extensive series of wetlands. However, for many of these wetlands, basic information about shorebirds communities like abundance, population trends, and richness are limited. Currently, wintering and stopover sites are critical for conservation because many populations of shorebirds have declined in the last decades. Marismas Nacionales (MN) is an important tropical wetland with a dynamic ecosystem and where shorebirds studies are limited to few wintering aerial and ground surveys. Our goals were analyzing shorebirds abundance and spatial and temporal distribution patterns in 2010-2011 season. We selected eight monitoring sites from two prospective visits to the study area. We observed shorebirds monthly between November 2010 and June 2011 to analyze richness and abundance patterns by site and month. Additionally, we describe specific spatial and temporal distribution for dominant species. A total of 27 shorebirds species and one genus, with a minimum global abundance of 136 236 individuals were found. Shorebird abundance at MN is among the most important in the region with around 10 % of total abundance in northwest Mexico; therefore, MN is a priority conservation site for this group of birds. Additionally, MN presents a suitable habitat for breeding of some shorebirds species such as Snowy and Wilson' Plover, Killdeer, Northern Jacana, Black-necked Stilt and Pacific American Oystercatcher. Dominant species were: Western Sandpiper (33.5 % of total in MN), American Avocet (31 %) and Dowitchers (17 %). These taxa are very common in others wetlands in Northwest Mexico region. Spatially, shorebirds were distributed in three sites: Chumbeño lagoon (37 % of abundance total), Las Garzas-Chihuin lagoons (24.2 %) and La Polca lagoon (24 %). The less used sites by shorebirds are located in the southern part of MN. Our results update MN information and can help to establish monitoring programs in the area.

3.
Artigo em Inglês | MEDLINE | ID: mdl-30810472

RESUMO

The cane sugar industry in Mexico depends heavily on the supply of energy, fossil fuels and material resources for its proper operation. The overuse of these resources plus the technical and technological deficiency causes severe environmental consequences. This scientific work aims to analyze the environmental damage attributable to cane sugar production following the life cycle assessment (LCA) methodology. System boundaries include sugarcane growing and harvesting, sugarcane transportation, sugar milling and electricity cogeneration from bagasse. The associated emissions were acquired from the SimaPro-Ecoinvent database, the Roundtable on Sustainable Biofuels (RSB) and the Agroscope Reckenholz-Tänikon Research Station (ART). The life cycle impact assessment (LCIA) was carried out by SimaPro 8.3.0 software and the characterization method used was IMPACT 2002+. The results show that sugarcane growing and harvesting stage provides the most harmful environmental impacts (52%) followed by electricity cogeneration (25.7%), sugarcane transportation (12.1%) and finally, sugar milling (10.2%). Regarding the environmental contributions at the endpoint categories, the highest percentage of impacts is found in the Human health category (53%), followed by Climate change (21%), Ecosystem quality (16%) and Resources (10%). The LCA in cane sugar production can support the decision-making process to deal with this environmental problem.


Assuntos
Mudança Climática , Produção Agrícola/métodos , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Indústria Alimentícia/métodos , Saccharum/crescimento & desenvolvimento , Biocombustíveis , Ecossistema , Humanos , México
4.
Rev. colomb. obstet. ginecol ; 36(4): 269-72, jul.-ago. 1985. ilus
Artigo em Espanhol | LILACS | ID: lil-1125

RESUMO

Se describen dos casos de síndrome de Poland (ausencia unilateral de mama y musculo pectoral). Su frecuencia es escasa en la clínica de mastología. Se describe la actitud diagnóstica y terapéutica en estas pacientes


Assuntos
Lactente , Adulto , Humanos , Feminino , Síndrome de Poland
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