Calidad biológica en cinco cultivos de leguminosas como coberturas en suelos degradados por minería aluvial en Madre de Dios

Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en SuelosMadre de Dios es una de las regiones con mayor producción de oro del país, siendo la pequeña y mediana minería la principal actividad económica de esta región. La minería aluvial informal incrementa la contaminación y destrucción medioambiental por deforestación y erosión de los suelos, sumado a esto, en nuestro país no existe una normativa o metodología desarrollada para recuperar las áreas degradadas por esta actividad. El objetivo de esta investigación fue evaluar el impacto de la instalación de cinco cultivos de cobertura, sobre la recuperación de un suelo degradado por minería aluvial en la comunidad nativa San Jacinto en el distrito de Tampobata en el transcurso de dos años de evaluación, generando un índice de calidad de suelos con los indicadores biológicos evaluados. Se utilizó el diseño experimental de Bloques Completamente al Azar (DBCA), con seis tratamientos y tres repeticiones: (i) canavalia (Canavalia ensiformis), (ii) centrosema (Centrosema macrocarpum), (iii) crotalaria (Crotalaria juncea), (iv) stylosanthes (Stylosanthes guianensis), (v) kudzu (Pueraria phaseoloides) y (vi) un testigo sin cobertura. Para la generación del índice los indicadores evaluados se normalizaron y ponderaron utilizando un análisis de componentes principales, adicionalmente se realizó un análisis de correlación de Spearman para ver la relación entre los distintos indicadores de suelos evaluados. Los cinco cultivos de cobertura mejoraron significativamente la calidad del suelo, las variables biológicas que mostraron una mejora significativa fueron los actinomicetos, hongos, bacterias fijadoras de N vida libre y bacterias nitrificantes. Respecto a la fertilidad del suelo, las coberturas aumentaron significativamente el potasio disponible, destacando kudzu, canavalia y stylosanthes, además aumentaron el porcentaje de agregados estables en el suelo. Estos resultados muestran que los cultivos de cobertura presentan gran potencial para el restablecimiento de la calidad del suelo.Madre de Dios is one of the regions with the highest gold production in Perú with small and medium-sized mining being the main economic activity in this region. Informal alluvial mining increases pollution and environmental destruction due to deforestation and soil erosion. In our country there is no regulation or methodology developed to recover the areas degraded by this activity. The purpose of this research was to evaluate the impact of the installation of five cover crops on the recovery of a soil degraded by alluvial mining in the San Jacinto native community in the Tampobata district in two years of evaluation developing a soil quality index with the biological indicators used. The randomized block design (RCBD) was used, with six treatments and three replicates: (i) canavalia (Canavalia ensiformis), (ii) centrosema (Centrosema macrocarpum), (iii) crotalaria (Crotalaria juncea), (iv) stylosanthes (Stylosanthes guianensis), (v) kudzu (Pueraria phaseoloides) and (vi) a control without cover. To generate the index, the evaluated indicators were normalized and weighted using a principal component analysis. Additionally, a Spearman correlation analysis was performed to see the relationship between the different soil indicators. The five cover crops significantly improved soil quality, in addition to the biological variables that showed a significant improvement were actinomycetes, fungi, free-living N-fixing bacteria and nitrifying bacteria. Regarding soil fertility, the covers significantly increased the available potassium, especially kudzu, canavalia and stylosanthes, and also increased the percentage of stable aggregates in the soil. These results show that the crops have great potential for restoring soil quality

Cultivos de cobertura asociados a quinua (Chenopodium quinoa Willd) en el Altiplano peruano: Reducción de la erosión, mejora de la salud del suelo y rendimiento agrícola

The Peruvian Altiplano presents increasing fertility losses, being susceptible to natural erosion. For many years, conventional agricultural management has generated losses of the topsoil and deterioration of soil properties, impacting in crop yields and deepening the degradation of this vulnerable ecosystem. The aim of this research was to determine the benefits of cover crops against erosion, soil health and quinoa yield. The trial was carried out in Huancarani and Cahualla towns, Mañazo district, Puno; with a randomized complete block design (RCBD) with four treatments: without cover and with clover (Medicago hispida G.), vetch (Vicia villosa) and mulch covers. We evaluated the physical, chemical, and biological characteristics of soil, the biomass of the cover crops and the quinoa yield. The results showed that the treatments with clover, mulch and vetch covers reduced soil erosion by 59.61%, 51.87% and 49.50%, respectively. Likewise, the use of clover and vetch covers increased organic carbon (29.71% and 31.16%), nitrogen (36.94% and 48.65%), and available phosphorus with clover cover (26.11%). Finally, clover cover associated with quinoa increased the yield of quinoa grain by 17% and reduced soil erosion significantly. These results show that cover crops have great potential for restoring soil health and improving yield.El Altiplano peruano presenta pérdidas crecientes de fertilidad, siendo a su vez susceptible a una erosión natural. Durante muchos años, un manejo agrícola convencional ha generado pérdidas de la capa superficial del suelo y deterioro de sus propiedades, teniendo gran impacto en el rendimiento de los cultivos y profundizando la degradación de este ecosistema vulnerable. El propósito de esta investigación fue evaluar el uso de cultivos de cobertura frente a la erosión, salud del suelo y rendimiento del cultivo de quinua. El ensayo se realizó en las localidades Huancarani y Cahualla, distrito Mañazo, provincia y región Puno. Se utilizó un diseño experimental de bloques completos al azar (DBCA) con cuatro tratamientos: sin cobertura y con coberturas de trébol (Medicago hispida G.), vicia (Vicia villosa) y mulch. Los resultados mostraron que la quinua asociada con coberturas de trébol, mulch y vicia redujeron la erosión del suelo en 59,61%, 51,87% y 49,50%, respectivamente. Asimismo, el uso de coberturas de trébol y vicia aumentó el carbono orgánico (+29,71% y 31,16%) y nitrógeno (+36,94% y 48,65%), y con el trébol, el fósforo disponible (+26,11%). Finalmente, la cobertura de trébol aumentó en 17% el rendimiento de la quinua en grano y redujo significativamente la erosión del suelo. Estos resultados muestran que los cultivos de cobertura presentan gran potencial para el restablecimiento de la salud del suelo y mejora en el rendimiento

Cultivos de cobertura asociados a quinua (Chenopodium quinoa Willd) en el Altiplano peruano: Reducción de la erosión, mejora de la salud del suelo y rendimiento agrícola

El Altiplano peruano presenta pérdidas crecientes de fertilidad, siendo a su vez susceptible a una erosión natural. Durante muchos años, un manejo agrícola convencional ha generado pérdidas de la capa superficial del suelo y deterioro de sus propiedades, teniendo gran impacto en el rendimiento de los cultivos y profundizando la degradación de este ecosistema vulnerable. El propósito de esta investigación fue evaluar el uso de cultivos de cobertura frente a la erosión, salud del suelo y rendimiento del cultivo de quinua. El ensayo se realizó en las localidades Huancarani y Cahualla, distrito Mañazo, provincia y región Puno. Se utilizó un diseño experimental de bloques completos al azar (DBCA) con cuatro tratamientos: sin cobertura y con coberturas de trébol (Medicago hispida G.), vicia (Vicia villosa) y mulch. Los resultados mostraron que la quinua asociada con coberturas de trébol, mulch y vicia redujeron la erosión del suelo en 59,61%, 51,87% y 49,50%, respectivamente. Asimismo, el uso de coberturas de trébol y vicia aumentó el carbono orgánico (+29,71% y 31,16%) y nitrógeno (+36,94% y 48,65%), y con el trébol, el fósforo disponible (+26,11%). Finalmente, la cobertura de trébol aumentó en 17% el rendimiento de la quinua en grano y redujo significativamente la erosión del suelo. Estos resultados muestran que los cultivos de cobertura presentan gran potencial para el restablecimiento de la salud del suelo y mejora en el rendimiento

COVID-19 anxiety, psychological well-being and preventive behaviors during the COVID-19 pandemic in Latin America and the Caribbean: relationships and explanatory model

This study assesses the relationship between COVID-19 anxiety and subjective well-being in terms of the mediating role of COVID-19 preventive behaviors. Additionally, the contribution of sociodemographic factors (sex and age) and risk perception on COVID-19 anxiety and its potential measurement invariance was tested in 5655 participants from 12 countries in Latin America and the Caribbean. A mixture of both latent and observable variables were analyzed using a system of structural equations. The Coronavirus Anxiety Scale (CAS), Preventive COVID-19 Infection Behaviors Scale (PCIBS) and single-item measures were used to assess the perceived probability of death, perceived severity and concern about transmitting COVID-19. The results indicated that there is a significant and relevant direct effect of COVID-19 anxiety on participants' well-being. Furthermore, COVID-19 anxiety significantly predicted both preventive behavior (β =.29, p <.01) and well-being (β = –.32, p <.01). The effects of COVID anxiety and preventive behavior explained 9.8% of the variance in well-being (R-square =.098); whereas, 8.4% of the variance in preventive behavior was associated with COVID anxiety (R-square =.084). Likewise, perceived likelihood of death from COVID, perceived severity of COVID, and concerns about COVID transmission were positively related to anxiety. Age was negatively related to anxiety, with men being less anxious than women. The results are invariant by country, i.e., the broad relationships found in the combined sample are also present in each individual country. The findings indicate that, although the exact relationships between variables may vary between countries, there are enough similarities to provide useful information about the impact of the COVID-19 pandemic in each of the countries included in the study

Cross-cultural validation of the new version of the Coronavirus Anxiety Scale in twelve Latin American countries

The Coronavirus Anxiety Scale (CAS) was recently developed to assess dysfunctional anxiety related to COVID-19. Although different studies reported that the CAS is psychometrically sound, it is unclear whether it is invariant across countries. Therefore, the present study aimed to examine the measurement invariance of the CAS in twelve Latin American countries (Argentina, Bolivia, Chile, Colombia, Cuba, Ecuador, El Salvador, Guatemala, Mexico, Paraguay, Peru, and Uruguay). A total of 5196 people participated, with a mean age of 34.06 (SD = 26.54). Multigroup confirmatory factor analysis (CFA) was used to examine the measurement invariance of the CAS across countries and gender. Additionally, the graded response model (GRM) was used to provide a global representation of the representativeness of the scale with respect to the COVID19 dysfunctional anxiety construct. The unidimensional structure of the five-item CAS was not confirmed in all countries. Therefore, it was suggested that a four-item model of the CAS (CAS-4) provides a better fit across the twelve countries and reliable scores. Multigroup CFA showed that the CAS-4 exhibits scalar invariance across all twelve countries and all genders. In addition, the CAS-4 items are more informative at average and high levels of COVID-19 dysfunctional anxiety than at lower levels. According to the results, the CAS-4 is an instrument with strong cross-cultural validity and is suitable for cross-cultural comparisons of COVID-19 dysfunctional anxiety symptoms in the general population of the twelve Latin American countries evaluated

COVID-19 Bereavement in Ten Latin American Countries: Measurement Invariance of the Pandemic Grief Scale and Its Relation to Suicidal Ideation

The present study aimed to evaluate the cross-cultural measurement invariance of the Pandemic Grief Scale (PGS) in ten Latin American countries. A total of 2,321 people who had lost a family member or other loved one due to COVID-19 participated, with a mean age of 34.22 years old (SD = 11.99). In addition to the PGS, a single item of suicidal ideation was applied. The unidimensional model of the PGS had adequate fit in most countries and good reliability estimates. There was evidence of measurement invariance by country and gender. Also, a one-point increase in the PGS was associated with an almost twofold increase in the odds of suicidal ideation. Scores greater than or equal to 4 on the PGS are proposed as a cut off to identify individuals with suicidal ideation. Strong evidence of the cross-cultural validity of the PGS is provided

Cross-Cultural Validation of a New Version in Spanish of Four Items of the Preventive COVID-19 Infection Behaviors Scale (PCIBS) in Twelve Latin American Countries

The invariance of the Preventive COVID-19 Infection Behaviors Scale (PCIBS) was evaluated in 12 Latin American countries (Argentina, Bolivia, Chile, Colombia, Cuba, Ecuador, El Salvador, Guatemala, Mexico, Paraguay, Peru, and Uruguay). A total of 5183 people from the aforementioned countries participated, selected using the snowball sampling method. Measurement invariance was assessed by multigroup confirmatory factor analysis (MG-CFA) and Multi-Group Factor Analysis Alignment (CFA-MIAL). In addition, item characteristics were assessed based on Item Response Theory. The results indicate that the original five-item version of the PCIBS is not adequate; whereas a four-item version of the PCIBS (PCIBS-4) showed a good fit in all countries. Thus, using the MG-CFA method, the PCIBS-4 achieved metric invariance, while the CFA-MIAL method indicated that the PCIBS-4 shows metric and scalar invariance. Likewise, the four items present increasing difficulties and high values in the discrimination parameters. The comparison of means of the PCIBS-4 reported irrelevant differences between countries; however, Mexico and Peru presented the highest frequency of preventive behaviors related to COVID-19. It is concluded that the PCIBS-4 is a unidimensional self-report measure which is reliable and invariant across the twelve participating Latin American countries. It is expected that the findings will be of interest to social and health scientists, as well as those professionals directly involved in public health decision making.Fil: Caicho Rodriguez, Tomás. Universidad Privada del Norte; PerúFil: Vilca, Lindsey W.. Universidad Peruana Unión; PerúFil: Valencia, Pablo D.. Universidad Nacional Autónoma de México; MéxicoFil: Carabajal Leon, Carlos. Universidad Privada del Norte; PerúFil: Vivanco Vidal, Andrea. Universidad Peruana de Ciencias Aplicadas (upc);Fil: Saroli Aranibar, Daniela. Universidad Peruana de Ciencias Aplicadas (upc);Fil: Reyes Bossio, Mario. Universidad Peruana de Ciencias Aplicadas (upc);Fil: White, Michael. Universidad Peruana Unión; PerúFil: Rojas Jara, Claudio. Universidad Catolica de Maule; ChileFil: Polanco Carrasco, Roberto. Cuadernos de Neuropsicología; ChileFil: Gallegos de San Vicente, Miguel Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto Rosario de Investigaciones en Ciencias de la Educación. Universidad Nacional de Rosario. Instituto Rosario de Investigaciones en Ciencias de la Educación; Argentina. Pontifícia Universidade Católica de Minas Gerais; BrasilFil: Cervigni, Mauricio Alejandro. Universidad Adventista del Plata. Secretaría de Ciencia y Técnica. Centro Interdisciplinario de Investigaciones En Ciencias de la Salud y del Comportamiento.; Argentina. Universidad Nacional de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Martino, Pablo Luis. Universidad Nacional de Rosario. Facultad de Psicología. Secretaria de Ciencia y Tecnología. Centro de Investigación En Neurociencias de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Palacios, Diego Alejandro. Universidad Mariano Gálvez de Guatemala; GuatemalaFil: Moreta Herrera, Rodrigo. Pontificia Universidad Católica del Ecuador; EcuadorFil: Samaniego Pinho, Antonio. Universidad Nacional de Asunción; ParaguayFil: Lobos Rivera, Marlon Elías. Universidad Tecnologica de El Salvador; El SalvadorFil: Ferrari, Ilka Franco. Pontifícia Universidade Católica de Minas Gerais; BrasilFil: Flores Mendoza, Carmen. Universidade Federal de Minas Gerais; BrasilFil: Buschiazzo Figares, Andrés. Instituto Alfred Adler Uruguay; UruguayFil: Puerta Cortéz, Diana Ximena. Universidad de Ibagué; ColombiaFil: Corrales Reyes, Ibraín Enrique. Universidad de Ciencias Médicas de Granma; CubaFil: Calderón, Raymundo. Universidad del Valle de Mexico; MéxicoFil: Pinto Tapia, Bismarck. Universidad Católica Boliviana San Pablo; BoliviaFil: Arias Gallegos, Walter L.. Universidad Católica San Pablo; Per

COVID-19 Bereavement in ten Latin American countries: Measurement invariance of the Pandemic Grief Scale and its relation to Suicidal Ideation

ABSTRACT The present study aimed to evaluate the cross-cultural measurement invariance of the Pandemic Grief Scale (PGS) in ten Latin American countries. A total of 2,321 people who had lost a family member or other loved one due to COVID-19 participated, with a mean age of 34.22years old (SD¼11.99). In addition to the PGS, a single item of suicidal ideation was applied. The unidimensional model of the PGS had adequate fit in most countries and good reliability estimates. There was evidence of measurement invariance by country and gender. Also, a one-point increase in the PGS was associated with an almost twofold increase in the odds of suicidal ideation. Scores greater than or equal to 4 on the PGS are proposed as a cut off to identify individuals with suicidal ideation. Strong evidence of the cross-cultural validity of the PGS is provided

Prevalence and predictors of intention to be vaccinated against COVID-19 in thirteen Latin American and Caribbean countries

The presence of a significant number of people who do not intend to be vaccinated could negatively impact efforts to control the COVID-19 pandemic. Therefore, this study sought to determine the prevalence of intention to be vaccinated against COVID-19 and associated sociodemographic and psychosocial factors in thirteen countries in Latin America and the Caribbean (LAC). A total of 5510 people from 13 LAC countries participated. Frequencies, percentages, bivariate analyses using chi-square tests, and Poisson regression analysis with robust variance were used. The countries with the highest prevalence of intention to be vaccinated were Brazil (96.94%), Cuba (89.59%), Chile (84.59%), and Mexico (78.33%). On the other hand, the countries with the lowest prevalence were El Salvador (54.01%), Paraguay (55.87%), and Uruguay (56.40%). Prevalence is also reported according to some sociodemographic and health variables. It was found that country, male sex, hours exposed to information about COVID-19, university education, living in an urban area, belief in the animal origin of the virus, perceived likelihood of contracting COVID-19, perceived severity of COVID-19, and concern about infecting others significantly predicted intention to be vaccinated in the 13 LAC countries. While most countries had a high prevalence of intention to be vaccinated, there are still subgroups that have levels of intention that may be insufficient to predict the presence of community immunity. In this sense, knowing the estimates of vaccination intention rates, as well as the associated sociodemographic and psychological factors, can be used to plan actions and interventions that will inform about the safety and benefits of vaccines, as well as strengthen trust in health authorities