Examinando por Autor "Oliva Cruz, Manuel"

Mostrando 1 - 18 de 18

An analysis of the rice-cultivation dynamics in the lower Utcubamba river basin using SAR and optical imagery in Google Earth Engine (GEE)
(MDPI, 2024-03-08) Medina Medina, Angel James; Salas López, Rolando; Zabaleta Santisteban, Jhon Antony; Tuesta Trauco, Katerin Meliza; Turpo Cayo, Efrain Yury; Huaman Haro, Nixon; Oliva Cruz, Manuel; Gómez Fernández, Darwin
One of the world’s major agricultural crops is rice (Oryza sativa), a staple food for more than half of the global population. In this research, synthetic aperture radar (SAR) and optical images are used to analyze the monthly dynamics of this crop in the lower Utcubamba river basin, Peru. In addition, this study addresses the need to obtain accurate and timely information on the areas under cultivation in order to calculate their agricultural production. To achieve this, SAR sensor and Sentinel-2 optical remote sensing images were integrated using computer technology, and the monthly dynamics of the rice crops were analyzed through mapping and geometric calculation of the surveyed areas. An algorithm was developed on the Google Earth Engine (GEE) virtual platform for the classification of the Sentinel-1 and Sentinel-2 images and a combination of both, the result of which was improved in ArcGIS Pro software version 3.0.1 using a spatial filter to reduce the “salt and pepper” effect. A total of 168 SAR images and 96 optical images were obtained, corrected, and classified using machine learning algorithms, achieving a monthly average accuracy of 96.4% and 0.951 with respect to the overall accuracy (OA) and Kappa Index (KI), respectively, in the year 2019. For the year 2020, the monthly averages were 94.4% for the OA and 0.922 for the KI. Thus, optical and SAR data offer excellent integration to address the information gaps between them, are of great importance to obtaining more robust products, and can be applied to improving agricultural production planning and management.
Distribution Models of Timber Species for Forest Conservation and Restoration in the Andean-Amazonian Landscape, North of Peru
(MDPI, 2020-09-25) Cotrina Sánchez, Dany A.; Barboza Castillo, Elgar; Rojas Briceño, Nilton B.; Oliva Cruz, Manuel; Torres Guzmán, Cristóbal; Amasifuen Guerra, Carlos Alberto; Bandopadhyay, Subhajit
The Andean-Amazonian landscape has been universally recognized for its wide biodiversity, and is considered as global repository of ecosystem services. However, the severe loss of forest cover and rapid reduction of the timber species seriously threaten this ecosystem and biodiversity. In this study, we have modeled the distribution of the ten most exploited timber forest species in Amazonas (Peru) to identify priority areas for forest conservation and restoration. Statistical and cartographic protocols were applied with 4454 species records and 26 environmental variables using a Maximum Entropy model (MaxEnt). The result showed that the altitudinal variable was the main regulatory factor that significantly controls the distribution of the species. We found that nine species are distributed below 1000 m above sea level (a.s.l.), except Cedrela montana, which was distributed above 1500 m a.s.l., covering 40.68%. Eight of 10 species can coexist, and the species with the highest percentage of potential restoration area is Cedrela montana (14.57% from Amazonas). However, less than 1.33% of the Amazon has a potential distribution of some species and is protected under some category of conservation. Our study will contribute as a tool for the sustainable management of forests and will provide geographic information to complement forest restoration and conservation plans.
Economic profitability of carbon sequestration of fine-aroma cacao agroforestry systems in Amazonas, Peru
(MDPI, 2024-03-08) Goñas Goñas, Malluri; Rojas Briceño, Nilton B.; Gómez Fernández, Darwin; Iliquín Trigoso, Daniel; Atalaya Marin, Nilton; Cajas Bravo, Verónica; Díaz Valderrama, Jorge R.; Maicelo Quintana, Jorge L.; Oliva Cruz, Manuel
Currently, the economic profitability of cocoa is being affected by the increasing incidence of pests, low selling prices, high production costs, and the presence of cadmium in cocoa farms, posing a potential risk of crop abandonment. Therefore, the objective of the present research was to evaluate the economic profitability of carbon sequestration of fine-aroma cacao agroforestry systems in Amazonas, Peru, using the economic indicators of NPV, EIRR, and the benefit–cost ratio. For this purpose, 53 small cocoa producers of the APROCAM cooperative were involved, from which data were obtained on the general characteristics of the production system, production and maintenance costs, indirect costs, and administrative costs; in addition, the costs of implementation and maintenance of an environmental services project were calculated to finally make a cash flow projected over 5 years. As part of the results, the economic analysis was carried out on 104.25 hectares of cocoa belonging to the total number of farmers evaluated, who reported an average yield of 957.32 kg of dry cocoa per he. In addition, it was found that the production cost is PEN 3.91/kg of dry cocoa, and the average selling price is PEN 7.38/kg of dry cocoa. After the economic analysis, it was found that the implementation of an environmental services project is profitable (NPV = PEN 1,454,547.8; EIRR = 44% and B/C = 1.86). These results open up an opportunity for cocoa farmers to diversify and increase their income by contributing to climate change mitigation.
Efectividad de áreas de conservación privada comunal en bosques montanos nublados del norte del Perú
(Instituto Pirenaico de Ecología, 2021-11-26) Delgado, Ellen; Mori, Gerson; Barboza Castillo, Elgar; Rojas Briceño, Nilton B.; Torres Guzmán, Cristóbal; Oliva Cruz, Manuel; Chavez Quintana, Segundo G.; Salas López, Rolando; López de la Lama, Rocío; Sevillano Ríos, C. Steven; Sarmiento, Fausto
Las Áreas de Conservación Privada (ACP) son uno de los mecanismos de conservación, gestionadas por ciudadanos privados que más protagonismo han adquirido en los escenarios de conservación local en los últimos años. En este estudio evaluamos la efectividad de cuatro ACP gestionadas por comunidades locales (CC). Se aplicó el Índice de Efectividad Compuesto (IEC) para determinar la efectividad del diseño, la integridad ecológica y la gestión. Los resultados muestran sistemas de gestión con una efectividad media, tres de las cuatro ACP evaluados (Copallín, Huaylla Belén-Colcamar y Tilacancha) reportan un diseño efectivo. Los rangos altitudinales protegidos están entre 2500 y 3500 m.s.n.m., con un índice de representatividad de la superficie promedio de 4,55% con respecto al área conservada en la categoría ACP para el departamento de Amazonas. La evaluación de la integridad ecológica indica que las ACP presentan menor superficie transformada (TS) (0-10%) y mayor TS en sus áreas circundantes, especialmente en el ACP Tilacancha (13,37% de TS en un buffer de 1,5 km). La suma ponderada de los índices individuales resulta en índices de efectividad compuestos de mayor a menor para el ACP Copallín (2,22), Hierba Buena Allpayacku (1,82), Huaylla Belen Colcamar (1,81) y Tilacancha (1,56).
Effect of Endophytic Trichoderma sp. Strains on the Agronomic Characteristics of Ecotypes of Theobroma cacao L. under Nursery Conditions in Peru
(Hindawi, 2022-05-24) Chavez Jalk, Antony; Leiva, Santos; Bobadilla Rivera, Leidy Gheraldine; Vigo Mestanza, Carmen Natividad; Arce, Marielita; Oliva Cruz, Manuel
Peru is one of the main producers of fine aroma native cacao, expanding its areas considerably in recent years, which makes it necessary to seek adequate management alternatives to obtain advantageous yields. The present work had the objective of testing the influence of Trichoderma sp. endophytic strains on the agronomic characteristics of ecotypes of Theobroma cacao L. under nursery conditions, Cajaruro district, Utcubamba, Amazonas, Peru. The Trichoderma strains evaluated were Trichoderma breve; T. harzianum; T. longibrachatum; T. afrojarzianum, and Trichoderma sp. which were inoculated on cocoa seedlings of ecotypes CCN51; TCHS565; and nativo fino de aroma. The variables evaluated were chlorophyll indices (at 30, 45, 60, and 70 days after planting), percentage of endophyte colonization, root hair development, trichomes on stems, and agronomic characteristics (plant height, number of leaves, stem diameter, root dry and fresh weight, root size, etc.). The results showed that the application of Trichoderma breve in the fine aroma native cocoa ecotype (T12) presented the highest chlorophyll index at 75 days after planting (DAP) with 43.53 +- 1.59 and 49.77 +- 2.42 for the apex and leaf base, respectively, with a percentage of colonization in the root hairs of 66.67%, and with better characteristics for the number of leaves with 12.00 +- 3.46. T12 showed positive influences for plant height, leaf number, and chlorophyll index. Treatments based on T. harzianum + CCN51 (T5) and T. afroharzianum + TSHS565 (T6) showed 100% colonization of the root hairs and trichomes on stems. Endophytic Trichoderma fungi are an alternative for organic production of fine aroma cocoa in Peru, improving the agronomic characteristics of the crop.
Global studies of cadmium in relation to Theobroma cacao: A bibliometric analysis from Scopus (1996 -2020)
(Universidad Nacional de Trujillo, 2021-12-15) García, Ligia; Angulo Castro, Fabio; Hernández Amasifuen, Angel David; Corazon Guivin, Mike Anderson; Alburquerque Vásquez, Javier; Guerrero Abad, Juan Carlos; Arellanos, Erick; Veneros, Jaris; Rojas Briceño, Nilton B.; Chavez Quintana, Segundo G.; Oliva Cruz, Manuel
En el año 2014, la Unión Europea impuso estándares máximos de tolerancia en cadmio, para la importación de productos a base de cacao, causando preocupación en los países. Se analizó estudios globales referidos a investigaciones en Theobroma cacao, relacionados con la actividad del cadmio en la atmósfera. Se utilizaron análisis bibliométricos en los programas R y VOSviewer, para examinar 64 documentos publicados en la base de datos Scopus según palabras clave. Se identificaron 811 palabras clave en coocurrencias de términos, 5 grupos temáticos en acoplamiento bibliográfico, 20 instituciones como afiliaciones más importantes, 20 países de procedencia de autores corresponsales, 112 instituciones en red de coautoría de los cuales 5 están en documentos primarios, y dos grupos en similaridad temática en co-citación de documentos. Estados Unidos lidera la producción científica con 11 documentos, seguido de Colombia (8) y Ecuador (7). En 1996 se registró el primer artículo científico para la red, con incrementos de hasta 11 publicaciones al 2020. En conclusión, se evidencia la necesidad de fortalecer y crear más redes de investigaciones entre países, instituciones, autores y coautores. Se espera que los resultados permitan desentrañar de manera integral la trayectoria de investigaciones cadmio-cacao, al tiempo que arrojen nuevas investigaciones prospectivas.
Identificación y selección de ecotipos de cacao nativo fino de aroma de la zona nor oriental del Perú
(Universidad Nacional Toribio Rodríguez de Mendoza, 2020-08-24) Oliva Cruz, Manuel; Maicelo Quintana, Jorge Luis
El Perú cuenta con una alta diversidad de recursos naturales, dentro de ellos es el cultivo de cacao, la zona nororiental es considerada como uno de los centros de origen más importante es éste cultivo. La presente investigación se realiza con el objetico de identificar y seleccionar ecotipos de cacao nativo fino de aroma de la zona nororiental del Perú, para ser incluidos en un banco de germoplasma y un centro de conservación de materiales genéticos promisorios. Cada ecotipo identificado y seleccionado cumplió exigencias estrictas para la elección de plantas, condiciones de vigorosidad, tolerancia a plagas y enfermedades, historial de rendimiento y calidad. Se logró identificar y seleccionar 146 ecotipos de cacao nativo fino de arma, ubicados en diversos pisos altitudinales, sin embargo, se encontró que la mayor diversidad de cacao se encuentra por encima de los 800 msnm.
In vitro biological activity of Beauveria bassiana, Beauveria peruviensis, and Metarhizium sp. against Hypothenemus hampei (Coleoptera: Curculionidae)
(Hindawi, 2023-09-30) Chuquibala Checan, Beimer; Torres de la Cruz, Magdiel; Leiva, Santos; Hernandez Diaz, Elgar; Rubio, Karol; Goñas Goñas, Malluri; Arce Inga, Marielita; Oliva Cruz, Manuel
Coffee (Coffea arabica) is the main commodity in Peru and is the economic support for thousands of small farmers. However, coffee production is affected by the coffee berry borer (Hypothenemus hampei). Currently, H. hampei is the most important pest in whole coffee-growing regions in Peru. This study aimed to evaluate in vitro biological activity of Beauveria bassiana, Beauveria peruviensis, and Metarhizium sp. against Hypothenemus hampei in two trials at different times. Conidia production, Conidia viability, and pathogenicity against H. hampei were evaluated at three concentrations (1 × 105, 1 × 107, and 1 × 109 conidia/mL−1). In addition, lethal times (LT50 and LT90) and lethal concentrations (LC50 and LC90) were calculated. There were significant differences in conidia production ( < 0.001) and conidia viability ( < 0.041). The highest conidia production and conidia viability were reached by B. bassiana and B. peruviensis, respectively. Likewise, there were differences in the pathogenicity of the strains in the two tests carried out (test 1: < 0.0009 and test 2: < 0.0001). The highest mortality occurred in the treatments of B. bassiana 1 × 109 conidia/mL−1, B. bassiana 1 × 107 conidia/mL−1, and B. peruviensis 1 × 109 conidia/mL−1. The treatments with lower LT50 and LT90 were B. bassiana 1 × 109 conidia/mL−1 and B. peruviensis 1 × 109 conidia/mL−1, and the strains with the lowest LC50 and LC90 were B. peruviensis and B. bassiana. The in vitro characteristics shown by B. bassiana and B. peruviensis conditions suggest they should be evaluated in the field to determine the capability of these strains to reduce populations of H. hampei.
Landsat images and GIS techniques as key tools for historical analysis of landscape change and fragmentation
(Elsevier, 2024-07-28) Gómez Fernández, Darwin; Salas López, Rolando; Zabaleta Santisteban, Jhon A.; Medina Medina, Angel J.; Goñas Goñas, Malluri; Silva López, Jhonsy O.; Oliva Cruz, Manuel; Rojas Briceño, Nilton B.
Monitoring and evaluation of landscape fragmentation is important in numerous research areas, such as natural resource protection and management, sustainable development, and climate change. One of the main challenges in image classification is the intricate selection of parameters, as the optimal combination significantly affects the accuracy and reliability of the final results. This research aimed to analyze landscape change and fragmentation in northwestern Peru. We utilized accurate land cover and land use (LULC) maps derived from Landsat imagery using Google Earth Engine (GEE) and ArcGIS software. For this, we identified the best dataset based on its highest overall accuracy, and kappa index; then we performed an analysis of variance (ANOVA) to assess the differences in accuracies among the datasets, finally, we obtained the LULC and fragmentation maps and analyzed them. We generated 31 datasets resulting from the combination of spectral bands, indices of vegetation, water, soil and clusters. Our analysis revealed that dataset 19, incorporating spectral bands along with water and soil indices, emerged as the optimal choice. Regarding the number of trees utilized in classification, we determined that using between 10 and 400 decision trees in Random Forest classification doesn't significantly affect overall accuracy or the Kappa index, but we observed a slight cumulative increase in accuracy metrics when using 100 decision trees. Additionally, between 1989 and 2023, the categories Artificial surfaces, Agricultural areas, and Scrub/ Herbaceous vegetation exhibit a positive rate of change, while the categories Forest and Open spaces with little or no vegetation display a decreasing trend. Consequently, the areas of patches and perforated have expanded in terms of area units, contributing to a reduction in forested areas (Core 3) due to fragmentation. As a result, forested areas smaller than 500 acres (Core 1 and 2) have increased. Finally, our research provides a methodological framework for image classification and assessment of landscape change and fragmentation, crucial information for decision makers in a current agricultural zone of northwestern Peru.
Morpho-Physiological response of four native accessions of Phaseolus vulgaris L. subjected to water stress under greenhouse conditions in northeastern Peru
(MDPI, 2024-09-06) Santillan Huaman, Anlly; Tejada Alvarado, José Jesús; García, Ligia; Vásquez García, Jheiner; Fernandez Huaytalla, Elizabeth; Vilca Valqui, Nuri Carito; Oliva Cruz, Manuel
Phaseolus vulgaris L. is a legume of high nutraceutical value, widely cultivated and consumed. However, common bean production faces challenges such as water stress that severely affects its growth and yield. This study evaluated the morphological and physiological response of four native P. vulgaris accessions subjected to different irrigation treatments under greenhouse conditions. A completely randomized design with factorial arrangement was used, evaluating three irrigation frequencies (100%, 50%, 25%) in combination with four accessions (PER1003541, PER1003542, PER1003543, PER1003544). The results showed that with the 25% irrigation treatment, PER1003544 showed a 54.62% decrease in leaf area, while PER1003542 and PER1003543 experienced reductions of 56.56% and 59.24%, respectively. In addition, accession PER1003544 reported a smaller reduction in the number of flowers and pods, with decreases of 40.21% and 29.9%, in contrast to PER1003543, which showed decreases of 60.66% and 52.63%, respectively. Accessions PER1003541 and PER1003544 also recorded the lowest reductions in dry biomass, with 31.85%and 35.41%, respectively. Regarding yield, PER1003544 and PER1003541 experienced reductions of 59.01% and 69.79%, respectively, unlike PER1003543, which showed a 90% decrease. In relation to stomatal density, PER1003541 recorded a reduction of 28.28%, while PER1003544 had a decrease of 37.10%, and PER1003543 experienced a reduction of 47.05%; chlorophyll content showed a similar trend. Finally, PER1003544 maintained a relatively stable stomatal index, with a reduction of 29.01%, compared to PER1003543, which reduced by 60.99%. In conclusion, accession PER1003544 stands out as a promising variety for breeding programs focused on water stress tolerance, contributing to food security and agricultural sustainability in areas affected by limited water availability. However, PER1003541 would be a suitable additional option, offering farmers flexibility in their crop selection according to the specific conditions of their environment.
Morphological, phylogenetic, and genomic evidence reveals the causal agent of thread blight disease of cacao in Peru is a new species of Marasmius in the section Neosessiles, Marasmius infestans sp. nov.
(F1000Research, 2024-01-29) Huamán Pilco, Ángel Fernando; Ramos Carrasco, Tito Ademir; Ernesto Franco, Mario Emilio; Tineo Flores, Daniel; Estrada Cañari, Richard; Romero, Pedro Eduardo; Aguilar Rafael, Vilma; Ramírez Orrego, Lourdes Adriana; Tincopa Marca, Rosalina; Márquez, Fanny Rosario; Oliva Cruz, Manuel; Díaz Valderrama, Jorge Ronny
The thread blight disease (TBD) of cacao (Theobroma cacao) in the department of Amazonas, Peru was recently reported to be caused by Marasmius tenuissimus (Sect. Neosessiles). This same species is known to be the main causal agent of TBD in West Africa. However, some morphological characteristics, such as the presence of rhizomorphs, the almost exclusively white color, and pileus sizes less than 5 mm, among others, differ to the description of M. tenuissimus. Therefore, we aimed to conduct a taxonomic revision of the cacao-TBD causal agent in Peru, by using thorough micro and macro morphological, phylogenetic, and nuclear and mitochondrial genomic approaches. We showed that the causal agent of TBD of cacao in Amazonas, Peru, belongs to a new species, Marasmius infestans sp. nov. This study enriches our knowledge of species in the Sect. Neosessiles, and strongly suggests that the M. tenuissimus species complex is highly diverse.
Optimizing landfill site selection using Fuzzy-AHP and GIS for sustainable urban planning
(Salehan Institute of Higher Education, 2024-06-01) Zabaleta Santisteban, Jhon Antony; Salas López, Rolando; Rojas Briceño, Nilton Beltrán; Gómez Fernández, Darwin; Medina Medina, Angel James; Tuesta Trauco, Katerin Meliza; Rivera Fernandez, Abner Shelser; Lévano Crisóstomo, José; Oliva Cruz, Manuel; Silva López, Jhonsy Omar
Careful landfill selection with minimal environmental impact is vital for urban planners. This study aims to identify suitable sites for controlled landfills using Fuzzy-AHP integrated with Remote Sensing and GIS, considering a 20-year projection of population and solid waste generation. Initially, twelve sub-criteria were identified, grouped into environmental, socio-economic, and physical categories, and then weighted using paired comparison matrices involving nine experts. The sub-criteria were rasterized and classified into four suitability levels. The weighted overlay of sub-criteria maps generated a territorial suitability model. Within the Alto Utcubamba Commonwealth (Amazonas, Peru), 0.069%, 41.70%, 66.934%, 0.20%, and 12.4% of the territory are suitable, moderately suitable, less suitable, unsuitable, and restricted, respectively, for landfill establishment. Subsequently, 16 highly suitable sites were selected based on the required area (S4 polygons ≥ 0.505 ha) in line with the projected solid waste generation over 20 years. Of the 16 selected areas, only 15 met the shape index. The model showed high accuracy (AUC = 0.784) during validation. Furthermore, this study provides a comprehensive framework for making decisions about waste management in developing countries, enhancing understanding of key factors in selecting landfill sites. It also offers a deeper insight into global and local factors that determine the suitability of landfill sites.
Phenotypic characterization of fine-aroma cocoa from Northeastern Peru
(Hindawi, 2021-07-05) Oliva Cruz, Manuel; Goñas Goñas, Malluri; García, Ligia M.; Rabanal Oyarse, Raúl; Alvarado Chuqui, Cástula; Escobedo Ocampo, Patricia; Maicelo Quintana, Jorge Luis
The phenotypic characterization of cacao (Theobroma cacao L.) plays an important role in the generation of information for the conservation of cacao germplasm. The objective of this study is to characterize phenotypically 146 ecotypes of fine-aroma native cacao (FFNC) from northeastern Peru that were collected from 280 to 1265 metres above sea level. Morphological descriptors of fruits and seeds, sensory characteristics, and productivity descriptors were used. The data obtained were analyzed using descriptive statistics with pie charts, distribution histograms, and multiple correspondence analysis. The results showed that 76.7% of the cocoa ecotypes had green immature fruits, 73% showed slight roughness on the surface of the fruit, 54% showed an intermediate thickness of the fruit wall, and 90% had the appearance of pairs of equidistant ridges. Regarding seed characteristics, 71% showed purplish cotyledons, with a high presence of floral and fruity notes and low levels of bitterness and astringency. Likewise, 52% of the fruits and 64% of the seeds were long. More importantly, cocoa beans needed to produce between 14 and 16 pods to obtain one kilogram of dry cocoa, which reflects a good level of productivity. Finally, there was a positive relationship between elevation levels and the presence of fine-flavoured native cocoa, i.e., the greatest diversity of native cocoa with floral and fruity notes was found above 501 metres above sea level.
Predicting potential distribution and identifying priority areas for conservation of the Yellow-tailed Woolly Monkey (Lagothrix flavicauda) in Peru
(Urban und Fischer Verlag GmbH und Co. KG, 2022-11-14) Guzman, Betty K.; Cotrina Sánchez, Alexander; Allauja Salazar, Elvis E.; Olivera Tarifeño, Christian M.; Ramos Sandoval, Jhonny D.; Hoyos Cerna, Marlon Y.; Barboza Castillo, Elgar; Torres Guzmán, Cristóbal; Oliva Cruz, Manuel
Species distribution models (SDMs) provide conservationist with spatial distributions estimations of priority species. Lagothrix flavicauda (Humboldt, 1812), commonly known as the Yellow-tailed Woolly Monkey, is one of the largest primates in the New World. This species is endemic to the montane forests of northern Peru, in the departments of Amazonas, San Martín, Huánuco, Junín, La Libertad, and Loreto at elevation from1,000 to 2,800 m. It is classified as “Critically Endangered” (CR) by the International Union for Conservation of Nature (IUCN) as well as by Peruvian legislation. Furthermore, it is listed in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Research on precise estimates of its potential distribution are scare. Therefore, in this study we modeled the potential distribution area of this species in Peru, the model was generated using the MaxEnt algorithm, along with 80 georeferenced occurrence records and 28 environmental variables. The total distribution (high, moderate, and low) for L. flavicauda is 29,383.3 km2, having 3,480.7 km2 as high potential distribution. In effect, 22.64 % (6,648.49 km2) of the total distribution area of L. flavicauda is found within Natural Protected Areas (NPAs), with the following categories representing the largest areas of distribution: Protected Forests (1,620.41 km2), Regional Conservation Areas (1,976.79 km2), and Private Conservation Areas (1,166.55 km2). After comparing the predicted distribution with the current NPAs system, we identified new priority areas for the conservation of the species. We, therefore, believe that this study will contribute significantly to the conservation of L. flavicauda in Peru.
Site Selection for a Network ofWeather Stations Using AHP and Near Analysis in a GIS Environment in Amazonas, NW Peru
(MDPI, 2021-11-28) Rojas Briceño, Nilton B.; Salas López, Rolando; Silva López, Jhonsy Omar; Oliva Cruz, Manuel; Gómez Fernández, Darwin; Terrones Murga, Renzo E.; Iliquin Trigoso, Daniel; Barrena Gurbillón, Miguel; Barboza Castillo, Elgar
Meteorological observations play a major role in land management; thus, it is vital to properly plan the monitoring network of weather stations (WS). This study, therefore, selected ‘highly suitable’ sites with the objective of replanning the WS network in Amazonas, NW Peru. A set of 11 selection criteria for WS sites were identified and mapped in a Geographic Information System, as well as their importance weights were determined using Analytic Hierarchy Process and experts. A map of the suitability of the territory for WS sites was constructed by weighted superimposition of the criteria maps. On this map, the suitability status of the 20 existing WS sites was then assessed and, if necessary, relocated. New ‘highly suitable’ sites were determined by the Near Analysis method using existing WS (some relocated). The territory suitability map for WS showed that 0.3% (108.55 km2) of Amazonas has ‘highly suitable’ characteristics to establish WS. This ‘highly suitable’ territory corresponds to 26,683 polygons (of ≥30 × 30 m each), from which 100 polygons were selected in 11 possible distributions of new WS networks in Amazonas, with different number and distance of new WS in each distribution. The implementation of this methodology will be a useful support tool for WS network planning.
Spatial analysis of environmentally sensitive areas to soil degradation using MEDALUS model and GIS in Amazonas (Peru): an alternative for ecological restoration
(MDPI, 2022-11-10) Meza Mori, Gerson; Torres Guzmán, Cristóbal; Oliva Cruz, Manuel; Salas López, Rolando; Marlo, Gladys; Barboza Castillo, Elgar
Land degradation is a permanent global threat that requires an interdisciplinary approach to addressing solutions in a given territory. This study, therefore, analyses environmentally sensitive areas to land degradation using the Mediterranean Desertification and Land Use (MEDALUS) and Geographic Information System (GIS) method through a multi-criteria approach in the district of Florida (Peru). For the method, we considered the main quality indicators such as: Climate Quality Index (CQI), Soil Quality Index (SQI), Vegetation Quality Index (VQI), and Management Quality Index (MQI). There were also identified groups of parameters for each of the quality indicators analyzed. The results showed that 2.96% of the study area is classified as critical; 48.85% of the surface is classified as fragile; 15.48% of the areas are potentially endangered, and 30.46% are not threatened by degradation processes. Furthermore, SQI, VQI, and MQI induced degradation processes in the area. Based on the results, five restoration proposals were made in the study area: (i) organic manure production, (ii) cultivated and improved pastures and livestock improvement, (iii) native forest restoration, (iv) construction of reservoirs in the top hills and (v) uses of new technologies. The findings and proposals can be a basic support and further improved by decision-makers when implemented in situ to mitigate degradation for a sustainable use of the territory.
Spatiotemporal Dynamics of Grasslands Using Landsat Data in Livestock Micro-Watersheds in Amazonas (NW Peru)
(MDPI, 2022-05-01) Atalaya Marin, Nilton; Barboza Castillo, Elgar; Salas López, Rolando; Vásquez Pérez, Héctor Vladimir; Gómez Fernández, Darwin; Terrones Murga, Renzo E.; Rojas Briceño, Nilton B.; Oliva Cruz, Manuel; Gamarra Torres, Oscar Ándres; Silva López, Jhonsy Omar; Turpo Cayo, Efrain
In Peru, grasslands monitoring is essential to support public policies related to the identification, recovery and management of livestock systems. In this study, therefore, we evaluated the spatial dynamics of grasslands in Pomacochas and Ventilla micro-watersheds (Amazonas, NW Peru). To do this, we used Landsat 5, 7 and 8 images and vegetation indices (normalized difference vegetation index (NDVI), enhanced vegetation index (EVI) and soil adjusted vegetation index (SAVI). The data were processed in Google Earth Engine (GEE) platform for 1990, 2000, 2010 and 2020 through random forest (RF) classification reaching accuracies above 85%. The application of RF in GEE allowed surface mapping of grasslands with pressures higher than 85%. Interestingly, our results reported the increase of grasslands in both Pomacochas (from 2457.03 ha to 3659.37 ha) and Ventilla (from 1932.38 ha to 4056.26 ha) micro-watersheds during 1990–2020. Effectively, this study aims to provide useful information for territorial planning with potential replicability for other cattle-raising regions of the country. It could further be used to improve grassland management and promote semi-extensive livestock farming.
Updating the distribution of Dicrodon guttulatum Duméril & Bibron, 1839 (Reptilia, Teiidae) with a disjunct population in the eastern slope of the Peruvian Andes
(Pensoft, 2022-05-11) García Bravo, Antonio; Guzman, Betty K.; Mendoza, Jani E.; Torres Guzmán, Cristóbal; Oliva Cruz, Manuel; Barboza Castillo, Elgar; Quiñones Rámirez, Jhon; Zabarburu Veneros, J. Luis; Venegas, Pablo J.
We report a disjunct population of Dicrodon guttulatum Duméril & Bibron, 1839 on the eastern slope of the Cordillera Occidental in the inter-Andean Seasonally Dry Forests of the Marañón River, in the Departments of Cajamarca and Piura in northwestern Peru. We include an updated range distribution map using records from museum specimens, the Global Biodiversity Information Facility, and available photographic records on iNaturalist. In addition, we identify widespread cultivation of rice crops as the main threat to D. guttulatum in the inter-Andean Seasonally Dry Forests of the Marañón.