Examinando por Autor "Saavedra Ramírez, Jorge"

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Carbon reserves in coffee agroforestry in the Peruvian Amazon
(Frontiers, 2024-12-11) Vallejos Torres, Geomar; Gaona Jimenez, Nery; Pichis García, Roger; Ordoñez, Luis; García Gonzales, Patricia; Quinteros , Aníbal; Lozano, Andi; Saavedra Ramírez, Jorge; Tuesta Hidalgo, Juan C; Reategui, Keneth; Macedo Cordova, Wilder; Baselly Villanueva, Juan Rodrigo; Marín, César
Secondary forests and coffee cultivation systems with shade trees might have great potential for carbon sequestration as a means of climate change adaptation and mitigation. This study aimed to measure carbon stocks in coffee plantations under different managements and secondary forest systems in the Peruvian Amazon rainforest (San Martín Region).
Carbon stocks in coffee farms and secondary forest systems in the Peruvian Amazon rainforest
(Research square, 2023-09-15) Vallejos Torres, Geomar; Gaona Jimenez, Nery; Ordoñez, Luis; Vallejos Torres, Andi; Mendoza Caballero, Wilfredo; Arévalo López, Luis Alberto; Saavedra Ramírez, Jorge; Macedo, Wilder; Reategui, Keneth; Baselly Villanueva, Juan Rodrigo; Marín, César
Secondary forests and coffee cultivation systems with shade trees might have great potential for carbon sequestration as a means of climate change adaptation and mitigation. This study aimed to measure carbon stocks in coffee plantations under different managements and secondary forest systems in the Peruvian Amazon rainforest (San Martín Region). The carbon stock in secondary forest trees was estimated using allometric equations, while carbon stocks in soil, herbaceous biomass, and leaf litter were determined through sampling and laboratory analysis. The biomass carbon stock in secondary forests was 132.2 t/ha, while in coffee plantations with Inga sp. shade trees it was 118.2 t/ha. Carbon stocks were 76.5 t/ha in coffee with polyculture farming, and the lowest amount of carbon was found in coffee without shade trees (31.1 t/ha). The carbon sequestered by coffee plants in all agroforestry systems examined had an average of 2.65 t/ha, corresponding to 4.63 % of the total carbon sequestered, being the highest stored in the coffee system with Inga sp. shade trees. A higher content of glomalin-related soil proteins (GRSP) was found in coffee without shade trees, with 18.5 mg/g. This is evidence that Inga sp. is the most compatible model of shade system for coffee farms. We recommend the conservation of secondary forests due to the greater biomass and carbon storage, and establishing coffee plantations with Inga sp. shade trees for its integral benefits, such as climate change mitigation.
Dominance of large trees in carbon storage of Peruvian Amazon forest
(Frontiers Media S.A., 2026-01-26) Lozano, Andi; Gaona Jimenez, Nery; Alvarado, Jaime W.; García Gonzáles, Patricia; Alva Arévalo, Alberto; Ordoñez, Luis; Saavedra Ramírez, Jorge; Tuesta Hidalgo, Juan C.; Vilela, Luis; Tuesta Hidalgo, Oscar A.; Baselly Villanueva, Juan Rodrigo; Chuchon Remon, Rodolfo Juan; Rengifo Del Águila, Sofía; Marin , César; Vallejos Torres, Geomar
Introduction: Forest carbon accumulation is crucial to mitigate ongoing climate change, as large individual trees store a substantial portion of the total carbon in biomass. In this study, large trees and carbon storage were estimated in five forests in the Peruvian Amazon. Methods: For the study, 100 plots were selected (twenty 500 m2 plots per forest site), distributed between 382 to 2086 meters above sea level. Various relationships were explored between the diameter at breast height (DBH) of the most abundant tree species and above- and below-ground carbon. The average carbon content in the tree was calculated based on 50% of the total tree volume at five sites of the Peruvian Amazon. Results: The site with most tree species (Alto Mayo Forest), had 59 tree species. The species Brosimum alicastrum, Ficus insipida, Manilkara bidentata, Inga sp., and Pourouma cecropiifolia showed an average aboveground carbon of 2.31, 3.09, 2.52, 2.78, 2.93 t ha-1, respectively, and values of 0.35, 0.48, 0.38, 0.42 and 0.43 t ha-1 of belowground carbon in trees with ≥ 46 cm DBH. Nectandra sp. showed an above and belowground carbon of 2.50 and 0.38 t ha-1 in trees with ≥ 46 cm DBH, while Cedrelinga catenaeformis showed averages of 5.21 and 0.74 t ha-1 of above and belowground carbon in trees with ≥ 61 cm DBH. Discussion: It was concluded that given the urgency of keeping carbon reserves out of the atmosphere, it is necessary to conserve trees larger than 41 cm, this also allows conserving forest biodiversity and microfauna by buffering the microclimate in the face of future climate changes.
Efecto de la altitud en la calidad del café (Coffea arabica L.): Comparación entre secado mecánico y tradicional
(Facultad de Ciencias Agropecuarias. Universidad Nacional de Trujillo, 2019-12-26) Guevara Sánchez, Maricely; Bernales del Águila, Carlos Iván; Saavedra Ramírez, Jorge; Owaki López, Johnny Jakson
El café es una de las bebidas de mayor consumo en el mundo entero. El proceso de secado para el almacenamiento de los granos café es determinante para las características físicas y sensoriales del producto final. El objetivo de este estudio fue evaluar el efecto de dos tipos de secado (mecánico y tradicional) en cinco altitudes sobre la calidad del café. La investigación se realizó en el valle del Alto Mayo, región San Martín, Perú. Se seleccionaron cinco fincas a diferentes altitudes (873, 1079, 1248, 1348, 1430 m.s.n.m.). El prototipo utilizado funciona mediante un sistema de túneles de calor térmico, construido con un micas solares y calaminas. Fueron extraídas 150 muestras de 1kg cada una. Las variables evaluadas fueron las características físicas y organolépticas del grano seco y el número de días de secado. Los resultados mostraron que no existieron diferencias significativas para ningún parámetro evaluado entre las altitudes seleccionadas. No obstante, existieron diferencias significativas para los parámetros de humedad y grano de primera categoría donde el secado mecánico fue superior. También, para el caso de la calidad organoléptica, el secado mecánico se presentó como mejor opción, indicando que su uso puede optimizar la calidad organoléptica del café.
Effects of Diet and Altitude on the Microbiota of the First Compartment of the Stomach in Peruvian Alpacas in Highland Puna Regions and Their Correlations with Blood Parameters
(MDPI, 2026-01-08) Flores Huarco, Nils H.; Estrada Cañari, Richard; Romero Avila, Yolanda Madelein; Coila, Pedro; Sanchez, Diana; Maicelo, Jorge L.; Alvarado, Wigoberto C.; Quilcate Pairazaman, Carlos Enrique; Aliaga, Mery; Galindo, Walter; Saavedra Ramírez, Jorge; Apaza, Henry; Arbizu, Carlos I.
This study explores the intestinal microbiota of eight 18-month-old male alpacas from two distinct high-altitude regions in Peru: the Wet Puna (4200 m above sea level) and the Dry Puna (4900 m above sea level). Using 16S rRNA and 18S rRNA metabarcoding, microbial communities of bacteria, archaea, fungi, and protists were analyzed from the first compartment of the stomach (C1) to investigate the diversity, taxonomic composition, and correlations with hematological parameters. Significant differences in microbial diversity and composition were observed between regions, driven by dietary and environmental factors. The Wet Puna exhibited greater alpha diversity in bacterial and fungal communities, while beta diversity highlighted distinct microbial compositions. Key taxa, such as Prevotella ruminicola and Acetitomaculum, were associated with energy metabolism and host adaptation, whereas methanogenic archaea (Methanobrevibacter, Methanosphaera) dominated in the Dry Puna, reflecting adaptations to arid conditions. Correlations between microbial taxa and hematological variables, such as Acetitomaculum with red blood cell count and Eremoplastron with neutrophil percentage, emphasize the complex interplay between microbiota and host physiology. These findings contribute to understanding microbial adaptations in high-altitude livestock and provide practical insights for enhancing alpaca management and conservation strategies through tailored nutritional approaches and sustainable grazing practices.
Evaluación del prendimiento y desarrollo de clones de caucho (Hevea brasiliensis) propagados por injerto en la selva peruana
(Universidad Autónoma de Yucatán, 2024-07-15) Navarro, Jorge M.; Alva Arévalo, Alberto; Lozano, Andi; Alva Arévalo, Celso Misael; García Gonzales, Patricia; Gaona Jimenez, Nery; Baselly Villanueva, Juan Rodrigo; Saavedra Ramírez, Jorge; Vallejos Torres, Geomar
The latex yield in Hevea brasiliensis trees is highly variable; Therefore, it is important to propagate commercial clones of this species by grafting in order to standardize or improve latex yields and therefore improve the economic income of producers in this part of the Amazon region. Objective. To evaluate the attachment and development of rubber clones propagated by grafting in the Peruvian jungle. Methodology. Nine-month-old patterns installed in the field were used. These were grafted with budding rods from the commercial clones TR-1, FX-3864, RRIM-600, IAN-873 and MDF-180. A completely randomized block design was used with five treatments and three blocks with 15 experimental units; each containing 30 repetitions. The data obtained were subjected to analysis of variance and Tukey's multiple range test (p<0.05) and the Kruskal Wallis test. Results. The best results in attachment and number of shoots were obtained in grafts with clone MDF-180 with values of 73.33 % and 7.83 shoots respectively; Regarding days to the appearance of the shoot and length, clone TR-1 presented it with 36.63 days and 27.47 cm; The largest leaf area was presented by the graft with clone IAN-873 with 55.46 cm2, while the highest chlorophyll content was obtained in grafts with clone RRIM-600 with 47.18 SPAD. Implications. More studies are required to establish the quality and adaptability of rubber clones propagated by grafting in different site conditions and establish patterns of tree productivity in a short time; Likewise, it is desired to evaluate the quality and quantity of latex produced by these clones. Conclusions. These results indicate the feasibility of propagating Hevea brasiliensis through shoot grafting in the field, which opens great possibilities for propagating rubber trees with better commercial characteristics, particularly with greater latex production.
Impact of forest degradation on soil properties in the Peruvian Amazon
(Springer Nature, 2026-01-16) Vallejos Torres, Geomar; Gaona Jimenez, Nery; Lozano, Andi; Saavedra , Harry; Alva Arévalo, Alberto; Ríos Vargas, Caleb; Saavedra Ramírez, Jorge; Tuesta Hidalgo, Juan; Tuesta Hidalgo, Oscar A.; Vilela, Luis; Valdez Andia, Manuel Jesús; Reategui, Keneth; Baselly Villanueva, Juan Rodrigo; Marín, César; Vento, Bárbara
Background: The Amazonian forests are increasingly threatened due to continuous changes in land use, particularly deforestation. This study aimed to quantify and analyze the vertical distribution of soil glomalin and its relationship with carbon, climate, and soil properties across three forest types of the Peruvian Amazon. A total of 18 plots were selected and sampled in forests with different vegetation cover types: deforested, disturbed, and primary forest. The vertical variation of total glomalin (TG), easily extractable glomalin (EEG), and the number of arbuscular mycorrhizal fungal (AMF) spores was estimated, as it was the relationships of these variables with soil depth, physical-chemical properties, and climate conditions. Results: The mean values for TG, EEG, and AMF showed vertical variations in the three forest cover types, with high values in disturbed forests and degraded soils. Overall, higher mean values were found in the surface soil layers compared to the deep layers. TG, EEG, and AMF were positively corelated with soil organic carbon (SOC) and soil organic matter (SOM). Moreover, the total nitrogen (N), SOC, OM, total phosphorus (P), and soil water content (SWC) presented higher values in the topsoil than the deep layers. Conclusions: The highest production of glomalin in disturbed forests is probably a response to degradation processes. This work is a contribution to expand knowledge about glomalin dynamics in forest soils of the Amazon rainforest and provides essential information for future soil ecosystem restoration practices in tropical forests.
Soil organic carbon balance across contrasting plant cover ecosystems in the Peruvian Amazon
(Instituto de Investigaciones Agropecuarias, INIA, 2023-10-31) Vallejos Torres, Geomar; Gaona Jimenez, Nery; Lozano, Andi; Paredes, Christopher I.; Lozano, Carlos M.; Alva Arévalo, Alberto; Saavedra Ramírez, Jorge; Arévalo López, Luis Alberto; Reategui, Keneth; Mendoza, Wilfredo; Baselly Villanueva, Juan Rodrigo; Marín, César
The Peruvian Amazon has been significantly affected by land use and climate change, decreasing decomposition processes, which cause a significant depletion of soil C stocks. In this study, we estimated soil organic C (SOC) mediated by different plant covers in coffee (Coffea arabica L.) plantations and secondary forests in several districts of the San Martín Region, Peru. We calculated the critical threshold, saturation point, and the organic C deficit of these Amazonian soils. The association between geography, soil physical-chemical characteristics, and SOC was estimated through principal component analysis. Across all sites of the study, SOC stock had an average value of 69.19 t ha-1, with 48.95 t ha-1 constituting inorganic C. The highest SOC stock (225.28 t ha-1) was observed under secondary forest in the Jepelacio district. The SOC stocks were positively correlated with altitude and CaCO3 content only in secondary forests. The current measured amount of organic C within 15 cm soil depth was 28.5 g C kg-1, which is very low and close to the critical threshold (20.6 g C kg-1) -estimated based on its clay and silt contents. Our SOC stocks measurements indicated a worrisome situation, as they are close to the critical threshold, which exposes this area to a greater and stronger degradation.