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Envíos recientes
- ÍtemAcceso AbiertoComposición bacteriana en suelos de cultivo de maca (Lepidium meyenii Walp) analizada mediante metagenómica: un estudio en los Andes centrales del Perú(2021-04-28) Custodio, María; Huaraca Meza, Fisher; Peñaloza, Richard; Alvarado Ibañez, Juan Carlos; De la Cruz Solano, HeidiEl cambio e intensificación de uso del suelo ha dado lugar al empobrecimiento de los suelos con efectos negativos en las comunidades biológicas. Se analizó la composición bacteriana de suelos de cultivo de maca (Lepidium meyenii Walp) mediante secuenciación Illumina en la meseta de Bombón, durante el año 2019. Se definieron tres sectores de muestreo, un sector control (suelo natural) y dos sectores con presión de uso (suelos “primer uso” y “segundo uso”, respecto al cultivo de maca). Se determinaron los indicadores fisicoquímicos del suelo mediante métodos analíticos y la composición de las comunidades bacterianas mediante secuenciación Illumina de los amplicones del gen de ARNr 16S. Los resultados de pH y CE, en suelos control y con presión de uso, variaron de 7,51 a 4,53 y de 0,06 a 0,47 dS/m, respectivamente. Los contenidos más altos MO, N, P, K y Ca se registraron en los suelos control disminuyendo significativamente en suelos con presión de uso. El análisis de componentes principales (ACP) presentó un porcentaje de variación total del 97,1 %. La secuenciación Illumina reveló 3776 familias bacterianas. El análisis SIMPER mostró que los mayores porcentajes de contribución lo realizaron las familias Acidobacteriaceae (2,95%), Verrucomicrobiaceae (2,68%), Thermoactinomycetaceae (2,11%) y Akkermansiaceae (2,10%). El análisis de redundancia (AR) mostró una buena asociación entre las variables fisicoquímicas y las familias bacterianas. El análisis metagenómico ha permitido identificar familias bacterianas que pueden ser usadas como indicadores de buena y mala calidad fisicoquímica del suelo según presión de uso por cultivos de maca; así como, a los mejores indicadores fisicoquímicos predictores de los cambios de la composición de las comunidades bacterianas.
- ÍtemAcceso AbiertoEcological risk due to heavy metal contamination in sediment and water of naturalwetlands with tourist influence in the central region of Peru(2021-08-18) Custodio, María; Fow, Anthony; Chanamé, Fernán; Orellana Mendoza, Edith; Peñaloza, Richard; Alvarado Ibañez, Juan Carlos; Cano, Deyvis; Pizarro, SamuelIn this study, the quality of sediment and surface water in two natural wetlands, Paca and Tragadero, in the central region of Peru was evaluated using pollution indices, including the geoaccumulation index, pollutant load index, modified pollution degree, potential ecological risk index, and site rank index, for four heavy metals. Principal component analysis was used to identify potential metal contaminant sources. The determination of Fe, Zn, Pb, and As was performed by flame atomic absorption spectrophotometry. The average concentrations of metals in the sediments of both lagoons decreased in the order Fe > Zn > Pb > As. The analysis of the contamination indices determined that As and Pb are the elements that contribute the most to environmental degradation in both wetlands. There is a strong correlation between the values of potential ecological risk and the modified degree of contamination, revealing that the Paca wetland has a moderate degree of contamination and potential ecological risk, while Tragadero presents a high degree of contamination and considerable potential ecological risk. The application of the site rank index showed that more than 50% of the sampling sites have between high and severe contamination. The principal component analysis presented 79.2% of the total variance. Finally, the results of this study are essential in order to carry out preventive actions for environmental protection in these lake ecosystems of great importance for many activities, such as bird watching.
- ÍtemAcceso AbiertoWater quality in small-scale coffee production units, Amazonas, Peru(2022-10-11) Morales Rojas, Eli; Chávez Quintana, Segundo; García, Magali; Veneros, Jaris; Oliva, Manuel; Santa Cruz Guerrero, José Carlos; Milla Pino, Manuel Emilio; Guivin Guadalupe, Alex Lenin; Sanchez Santillan, TitoThe objective of this research was to determine water quality in small-scale coffee production units in the Amazon Region, Peru. The characterization of the factors associated with coffee farmers was collected through surveys. The Standard Methods for the Examination of Water and Wastewater (APHA) method was used to determine the physicochemical and microbiological parameters of the incoming water (AE) (water for human consumption) and the outgoing water (AS) (wastewater from coffee washing). The results indicated that the coffee growers do not have adequate technology for washing the coffee and that they use water for these activities. In the characterization of the water, significant differences were found between the parameters of the AE and the AS, where the pH of the AE ranged from 7.00 to 7.32 and the pH of the AS from 3.76 to 4.44. The turbidity of the AS showed high values of 1814.47 NTU. Total Coliforms (TC) and heavy metals such as copper and chromium all increased in value up to 0.20 and 0.15 ppm in the AS compared to the AE. The characteristics of the water quality consumed by the coffee growers are poor and values above Peruvian standards were found.
- ÍtemAcceso AbiertoSocial factors associated with poverty in households in Peru(2022-12-13) Quispe Mamani, Julio Cesar; Aguilar-Pinto, Santotomas Licimaco; Calcina Álvarez, Dominga Asunción; Ulloa-Gallardo, Nelly Jacqueline; Madueño Portilla, Roxana; Vargas Espinoza, Jorge Luis; Quispe Mamani, Félix; Cutipa Quilca, Balbina Esperanza; Tairo Huamán, Ruth Nancy; Coacalla Vargas, ElizaldeThe objective of the research was to identify the determinants of poverty at the household level in Peru in 2020. The research design was descriptive and correlational, with a type of nonexperimental research and quantitative approach, and considered the logit econometric model; the sources of information used correspond to the National Household Survey of the National Institute of Statistics and Informatics, from which the variables that are considered determinants of poverty were extracted and managed. It was determined that the size of the household positively influences by 1.3%; the economic income of the head of household negatively influences by 0.000828%; the years of education of the head of household influences by 0.1%; homeownership influences by 0.9%; access to social programs of food and non-food aid influence by 0.9% and 0.6%, respectively; access to drinking water service, hygienic service and electric power service have a negative influence of 1.8%, 0.6% and 1.7%; all these factors are associated with the poverty of households in Peru. Therefore, the social determinants of poverty were household size, economic income, years of education, access to homeownership, access to a social food aid program, access to a social non-food aid program, access to drinking water services, access to hygienic services and access to electric power services.
- ÍtemAcceso AbiertoEvaluation of heavy metals in vegetables from two origins marketed in northern Peru(2022-07-08) Grández, J.; Oliva, M.; Morales, E.; Goñas, M.; Chavez, S.; Guivin, A.; Quiñonez, L.; Milla, M.The objective of the study was to evaluate the concentration of arsenic, chromium, cadmium, and lead in onion (Allium fistulosum and Allium cepa), tomato (Solanum lycopersicum), and celery (Apium graveolens) from two origins (local - Chachapoyas province and from the coast-province of Chiclayo) that are sold in the model market of the city of Chachapoyas. Six samples were taken on three different dates in November 2020, which were collected by non-probabilistic sampling (by convenience), which allowed choosing the most appropriate sample (according to its origin). For the determination of heavy metals, the Agilent 4100 MP-AES spectrometer was used. The concentration of As, Cr, and Cd in the vegetables remained below the Maximum Allowable Limits of the international standards with which they were compared; however, the concentration of Pb exceeded the Maximum Allowable Limits in all the samples analyzed, obtaining the lowest value in the celery samples from the local origin (0.15 mg.kg-1) and the highest value in the tomato samples from the coast (0.21 mg.kg-1). Therefore, it is concluded that only Pb is higher than the Maximum Allowable Limits with which it was compared.
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