ABSTRACT: This study evaluated the effect of removing apical dominance at phenological stages on the agronomic traits of soybean cultivars. The experiment was conducted in the 2020/2021 growing season inthe teaching-experimental area of the Federal Institute of Education, Science and Technology of Rio Grande do Sul, Campus Ibirubá, under a randomized block design in a split-plot arrangement, with three replications. The main plots were composed of five soybean cultivars (DM53i54 IPRO, Zeus IPRO, Lanza IPRO, DM5958 IPRO, and Delta IPRO), and the subplots consisted of the phenological stages of apical dominance removal (control, V2, V4, and V6). Morphological traits were evaluated at different stages. Differences were observed between cultivars, which followed their pre-defined morphologies. Apical dominance removal reduced aspects such as the number of nodes and legumes on the main stem and the first legumeinsertion height. Cultivars developed branching mechanismsas a compensation strategy, increasing the number of legumes on the branches by up to 130%. The removal of the shoot apex can modify morphological aspects in soybean plants,but their yield tends to be maintained. ABSTRACT 20202021 2020 2021 2020/202 teachingexperimental teaching experimental Education Sul Ibirubá splitplot split plot arrangement replications DM53i54 DMi DM i (DM53i5 IPRO DM595 , IPRO) control, control (control V2 V V4 V6. V6 . V6) predefined pre defined morphologies height strategy 130 130% plantsbut plants but maintained 2020202 202 2020/20 DM53i5 (DM53i DM59 13 202020 20 2020/2 DM53i DM5 1 20202 2 2020/

RESUMO: O presente artigo objetiva avaliar o efeito da remoção da dominância apical em estádios fenológicos, nos caracteres agronômicos de cultivares de soja. O experimento foi implantado na área didática-experimental do Instituto Federal de Educação e Tecnologia do Rio Grande do Sul, Campus Ibirubá, na safra 2020/2021, sob delineamento de blocos ao acaso, em arranjo de parcelas subdivididas, com três repetições. As parcelas principais eram compostas pelos cinco cultivares (DM53i54 IPRO, Zeus IPRO, Lança IPRO, DM5958 IPRO e Delta IPRO) e as subparcelas, pelos estádios fenológicos de remoção de dominância apical (testemunha, V2, V4 e V6). As características morfológicas foram avaliadas em diferentes estádios. Como resultados, verificaram-se diferenças entre os cultivares, que seguiram suas morfologias pré-definidas. A remoção de dominância apical, reduziu aspectos como o número de nós e legumes na haste principal, além da altura de inserção do primeiro legume. Como estratégia de compensação, os cultivares desenvolvem mecanismos de ramificação, acrescendo até 130% no número de legumes nos ramos. Verifica-se que a remoção do ápice caulinar é capaz de modificar aspectos morfológicos em plantas de soja, contudo, seu rendimento tende a ser mantido. RESUMO soja didáticaexperimental didática experimental Sul Ibirubá 20202021 2020 2021 2020/2021 acaso subdivididas repetições DM53i54 DMi DM i (DM53i5 DM595 subparcelas testemunha, testemunha (testemunha V2 V V6. V6 . V6) resultados verificaramse verificaram se prédefinidas. prédefinidas pré definidas. definidas pré-definidas principal legume compensação ramificação 130 ramos Verificase Verifica contudo mantido 2020202 202 2020/202 DM53i5 (DM53i DM59 13 202020 20 2020/20 DM53i DM5 1 20202 2 2020/2 2020/

ABSTRACT: One of the causes of productivity loss in sugarcane cultivation has been associated with the species Diatraea saccharalis, also known as the sugarcane borer. Therefore, this study evaluated the feasibility of using hyperspectral sensors to obtain the leaf spectral response of sugarcane in different periods of infestation at leaf and canopy levels to diagnose D. saccharalis damage in advance. The study included three varieties of sugarcane: CTC9003BT, CTC4, and RB966928. The insecticide Altacor® was used to control pestsin half of the plots. Data collection occurred at the following stages: sprouting, tillering, stalke longation, and early maturation. Data regarding relative water content (RWC), leaf spectral signature in the laboratory and canopy, vegetation indices (NDVI and MCARI), productivity, purity, and total recoverable sugar (TRS) were collected to evaluate the borer effects on the sugarcane crop. The highest RWC was observed for CTC9003BT (60.15%) without insecticide and 59.0% with insecticide. The visible (400-680 nm) and near-infrared (750-1300 nm) spectral bands identified spectral variations in plants with and without sugarcane borer. The percentage of sugarcane borer showed high and negative correlations between productivity, NDVI, and TRS, with coefficients of -0.68, -0.76, and -0.76, respectively. The NDVI and MCARI indices effectively detect plants under stress, but their variation is influenced by multiple factors, making it difficult to associate them with a single problem (sugarcane borer). ABSTRACT Therefore D advance CTCBT CTC BT CTC4 RB966928 RB Altacor plots stages sprouting tillering longation maturation RWC, , (RWC) MCARI, MCARI) purity TRS (TRS crop 60.15% 6015 60 15 (60.15% 590 59 0 59.0 400680 400 680 (400-68 nm nearinfrared near infrared 7501300 750 1300 (750-130 0.68, 068 68 -0.68 0.76, 076 76 -0.76 respectively stress factors . borer) RB96692 (RWC 60.15 601 6 1 (60.15 5 59. 40068 40 (400-6 750130 75 130 (750-13 0.68 06 -0.6 0.76 07 7 -0.7 RB9669 60.1 (60.1 4006 4 (400- 75013 13 (750-1 0.6 -0. 0.7 RB966 60. (60. (400 7501 (750- 0. -0 RB96 (60 (40 (750 - RB9 (6 (4 (75 ( (7

RESUMO: Uma das causas de perda de produtividade em lavouras de cana está associada à espécie Diatraea saccharalis, também conhecida por broca da cana. Portanto, este estudo avaliou a viabilidade do uso de sensores hiperespectrais para obter a resposta espectral foliar da cana-de-açúcar em diferentes períodos de infestações, tanto a nível foliar quanto dossel, a fim de diagnosticar antecipadamente os danos da Diatraea saccharalis. O estudo contou com três variedades de cana-de-açúcar: CTC9003BT, CTC4 e RB966928. Em metade das parcelas foi utilizado o inseticida Altacor® para o controle de pragas. As coletas de dados ocorreram nas fases: brotação, perfilhamento, crescimento de colmos e início da maturação. Para avaliar os efeitos da broca na cana foi coletado os dados referentes ao conteúdo relativo de água (CRA), assinatura espectral foliar em laboratório e dossel, índices de vegetação (NDVI e MCARI), produtividade, pureza e ATR (Açúcar Total Recuperável). O maior CRA encontrado foi para a CTC9003BT (60,15%) sem inseticida e 59,0% com inseticida. As faixas espectrais do visível (400-680 nm) e infravermelho próximo (750-1300 nm) identificaram variações espectrais nas plantas com e sem broca. O percentual de broca apresentou correlações altas e negativas entre a produtividade, NDVI e ATR, com coeficientes de -0,68, -0,76 e -0,76, respectivamente. Os índices NDVI e MCARI foram eficazes na detecção de plantas sob estresse, contudo, sua variação é influenciada por múltiplos fatores, sendo difícil associá-los a um único problema (broca). RESUMO saccharalis Portanto canadeaçúcar açúcar infestações dossel CTCBT CTC BT RB966928 RB Altacor pragas fases brotação perfilhamento maturação CRA, , (CRA) MCARI, MCARI) Açúcar Recuperável. Recuperável . Recuperável) 60,15% 6015 60 15 (60,15% 590 59 0 59,0 400680 400 680 (400-68 nm 7501300 750 1300 (750-130 0,68, 068 68 -0,68 0,76 076 76 -0,7 0,76, respectivamente estresse contudo fatores associálos associá los (broca) RB96692 (CRA 60,15 601 6 1 (60,15 5 59, 40068 40 (400-6 750130 75 130 (750-13 0,68 06 -0,6 0,7 07 7 -0, (broca RB9669 60,1 (60,1 4006 4 (400- 75013 13 (750-1 0,6 0, -0 RB966 60, (60, (400 7501 (750- - RB96 (60 (40 (750 RB9 (6 (4 (75 ( (7

Abstract Introduction. Climate change adaptation measures require informed decision-making. However, small-scale agriculture shows low rates of technology adoption due to cost and lack of connectivity. Objective. To evaluate three low-cost prototypes of small-scale agriculture devices for soil moisture measurement in different soil textures, as well as to determine the respective calibration equations, and the effects of electrical conductivity and temperature on moisture measurement. Materials and methods. Three measurement and recording prototypes for soil moisture were evaluated in soils with variations in clay/sand content and electrical conductivity in productive plots at Zamorano University in Honduras and a demonstration farm in Popayán, Colombia during the first quarter of 2022. Commercial sensors were used as a reference to compare the performance of the prototypes through regression analysis of hourly sensor readings over 90 days. Electrical conductivity (dS/m) and temperature variables were collected to determine their influence on moisture reading accuracy. Results. The soil moisture measurement devices showed better performance in soils with lower sand content. The measurement from the devices overestimated moisture readings by 0.19 to 0.52 percentage points for each additional degree of soil temperature. Additionally, for each additional dS/m of electrical conductivity, the reading needed adjustment by 8 to 55 percentage points. Conclusions. Prototype A was the most accurate device, while prototype B was the most precise compared to commercial sensors. Soil moisture devices performed best in soils with lower sand content. The three models evaluated performed best in loam soil with a medium clay content.

Resumen Introducción. Las medidas de adaptación al cambio climático requieren de la toma de decisiones informadas. Sin embargo, la agricultura de pequeña escala muestra bajas tasas de adopción de tecnologías por su costo y falta de conectividad. Objetivo. Evaluar tres prototipos de dispositivos para agricultura de pequeña escala y de bajo costo para medir humedad de suelo en diferentes texturas, así como determinar las respectivas ecuaciones de calibración y los efectos de conductividad eléctrica y temperatura en la medida de humedad. Materiales y métodos. Se evaluaron tres prototipos de dispositivos de medición y registro de humedad de suelo, en suelos con diferencial en contenido de arcilla/arena y conductividad eléctrica en parcelas productivas de la Universidad Zamorano, en Honduras; y Finca demostrativa en Popayán, Colombia, durante el primer trimestre del 2022. Se tomaron como referencia sensores comerciales para la comparación del desempeño de los prototipos, mediante análisis de regresión de las lecturas por hora de los sensores durante 90 días. Se recolectaron las variables de conductividad eléctrica (dS/m) y temperatura para determinar la influencia en la precisión de la lectura de humedad. Resultados. Los dispositivos de medición y registro de humedad presentaron un mejor desempeño en suelos con menor contenido de arena. La medición de los dispositivos sobrestimó entre 0,19 y 0,52 puntos porcentuales la lectura de humedad por cada grado adicional de temperatura del suelo, y que por cada dS/m adicional de conductividad eléctrica la lectura se debe ajustar entre 8 y 55 puntos porcentuales. Conclusiones. El prototipo A fue el dispositivo más exacto, mientras que el prototipo B fue el más preciso, con respecto a los sensores comerciales. Los dispositivos de humedad presentaron un mejor desempeño en suelos con menor contenido de arena. Los tres modelos evaluados obtuvieron el mejor desempeño en suelo franco con contenido medio de arcilla.

Abstract Introduction. Estimating crop evapotranspiration (ETc) helps determine water requirements, enabling the proposal of irrigation techniques that save water. Objective. To use remotely piloted aircraft system (RPAs) for greater precision in measuring evapotranspiration in rice fields, aiming to reduce water consumption. Materials and methods. The study utilized a randomized complete block design with a factorial structure of two experiments: flooded irrigation (E1) and irrigation with controlled drying (E2), and three rice varieties (IR43, IR71706, Sahod Ulan 12). The study was conducted at the Experimental Irrigation Area (AER) of the Universidad Nacional Agraria La Molina, Peru. Eight RPAS flights were carried out between January and February 2019, distributed between the tillering and cotton point stages. Results. The combined analysis of treatments using analysis of variance (ANOVA) and Duncan’s test with p < 0.05 revealed a significant difference in ETc between E1 and E2. However, no significant difference was found between the rice varieties. Maximum values of ETc and yield were obtained for E1 at 4.50 mm/day and 10389 kg/ha, and for E2 at 3.7 mm/day and 9710 kg/ha, respectively. Conclusions. The use of a remotely piloted aircraft system improved the temporal and spatial resolution of multispectral and thermal images, providing greater accuracy in crop evapotranspiration (ETc) under two irrigation regimes. Controlled drying irrigation resulted in a A 24% reduction in ETc, allowing for a water saving of 855 m3/ha.

Resumen Introducción. La estimación de la evapotranspiración del cultivo (ETc) permite conocer los requerimientos de agua del cultivo, que ayudan a proponer técnicas de riego con ahorro de agua. Objetivo. Usar el sistema de aeronave pilotada remotamente (RPAs) para mayor precisión de la evapotranspiración en arrozales a fin de reducir el consumo de agua. Materiales y métodos. Para el estudio la distribución de parcelas siguió un diseño de bloques completamente al azar con estructura factorial de dos experimentos: riego inundado (E1) y riego con secas controladas (E2), y tres variedades de arroz (IR43, IR71706, Sahod Ulan 12); se llevó a cabo en el Área Experimental de Riego (AER) de la Universidad Nacional Agraria La Molina, Perú. Entre enero y febrero del 2019 se realizaron ocho vuelos, de un RPAs, distribuidos entre las etapas de macollamiento y punto de algodón. Resultados. El análisis combinado de tratamientos con análisis de varianza y prueba de Duncan con p < 0,05, reveló diferencia significativa de la ETc, entre E1 y E2. Sin embargo, no se encontró diferencia significancia entre las variedades de arroz. Se obtuvo valores máximos de ETc y rendimiento para E1 de 4,50 mm/d y 10 389 kg/ha, y para E2 de 3,7 mm/d y 9710 kg/ha, respectivamente. Conclusiones. El uso de un sistema de aeronave pilotada remotamente permitió mejorar la resolución temporal y espacial de las imágenes multiespectrales y térmicas para obtener mayor precisión en la evapotranspiración del cultivo (ETc) bajo dos regímenes de riego. En el riego con secas controladas se obtuvo una reducción del 24 % de la ETc lo que permitió un ahorro de agua de 855 m3/ha.

Abstract Introduction. The soil and climatic conditions of Ecuador are ideal for rice cultivation, yields are higher than the world average, but agronomic management leads to an increase of cadmium in the soil, which can reach the grain by translocation, which affects its safety. Objetive. To evaluate the absorption of cadmium through the omission of macronutrients technique in six soils of Ecuador and its effect on the vegetative development of rice crops. Materials and methods. The trial was carried out at the Pichilingue Tropical Experimental Station of the National Institute of Agricultural Research, Ecuador, during 2018. Nine treatments were studied: 1) Without fertilization and without Cd (control 1), 2) without fertilization and with Cd (Control 2), 3) Complete fertilization and six omission treatments of one nutrient at a time, a completely randomized block design of experiments, divided plots and three repetitions was used. The variables evaluated were those related to the production of dry matter in the root and aerial part. For the comparison between means, the Tukey test was used (p<0.05). Results. Nutrients omissions (N and P) led to reduced Cd absorption, which decreased dry matter production, particularly in very acidic or alkaline soils such as in Sucumbíos (pH 4) and Guayas (pH 7, 9), respectively. Conclusions. The absorption of cadmium in rice plants was reduced to a greater extent with the omission of the macronutrients N and P, mainly in the soils of Sucumbíos, Los Ríos, El Oro and Manabí, the nutrient omission technique also affecting the production of dry matter and yields, also observing that a pH below 5 or higher than 7.9 affects the absorption of cadmium in the soils studied.

Resumen Introducción. Las condiciones edafoclimáticas del Ecuador son ideales para el cultivo del arroz, los rendimientos son mayores al promedio mundial, pero su manejo agronómico conlleva a un aumento de cadmio en el suelo, que puede llegar al grano por translocación, lo cual afectan su inocuidad. Objetivo. Evaluar la absorción de cadmio mediante la técnica de omisión de macronutrientes en seis suelos del Ecuador y su efecto sobre el desarrollo vegetativo del cultivo de arroz. Materiales y métodos. El ensayo se realizó en la Estación Experimental Tropical Pichilingue del Instituto Nacional de Investigaciones Agropecuarias, Ecuador, durante el año 2018. Se estudiaron nueve tratamientos 1) Sin fertilización y sin Cd (testigo 1), 2) sin fertilización y con Cd (Testigo 2), 3) Fertilización completa y seis tratamientos de omisión de un nutriente a la vez, se usó un diseño de experimentos de bloques completamente al azar, parcelas divididas y tres repeticiones. Las variables evaluadas fueron las relacionadas a la producción de materia seca en raíz y parte aérea. Para la comparación entre medias, se utilizó la prueba de Tukey (p<0,05). Resultados. Las omisiones de los nutrientes (N y P) llevaron a la reducción de la absorción del Cd, que disminuyó la producción de materia seca, en particular en los suelos muy ácidos o alcalinos como en Sucumbíos (pH 4) y Guayas (pH 7,9), respectivamente. Conclusiones. La absorción de cadmio en plantas de arroz se redujo en mayor medida con la omisión de los macronutrientes N y P, principalmente en los suelos de Sucumbíos, Los Ríos, El Oro y Manabí, afectando también la omisión de nutrientes a la producción de materia seca y los rendimientos, observándose además que un pH por debajo de 5 o superior a 7,9 afecta la absorción de cadmio en los suelos estudiados

Summary: The fraction of vegetation cover (FVC) and the Leaf Area Index (LAI) are biophysical variables closely related to the evapotranspiration rate of crops and their biomass production. Despite their importance, they are usually not measured directly due to their time-consuming and costly nature; however, they can be estimated on a large scale and near-real-time using spectral information captured in satellite images, although this requires prior validation at the field level. Simple linear regression models were developed and validated using 13 vegetation indices (VI) related to LAI and FCV in alfalfa (Medicago sativa). Three spectral information sources were used: (i) reflectance to derive the VI; (ii) digital photographs processed with the Canopeo application to estimate FVC; and (iii) direct LAI measurements using a ceptometer. Six field samples were taken between March and June, 2020 in four alfalfa plots located in Palmar de Bravo, Puebla, Mexico. To evaluate each VI, the determination coefficient (R2) and the root mean square error (RMSE) were used. We found that the most suitable VI for estimating FVC was the VIgreen (Green Vegetation Index, R2 =0.987 and RMSE = 0.093). For the LAI, the VI that performed best was the NDVI (Normalized Difference Vegetation Index, R2 = 0.935 and RMSE = 0.746). The results showed the suitability and practical utility of spectral information for estimating biophysical variables in alfalfa cultivation and their monitoring.

Resumen: La fracción de cobertura vegetal (FCV) y el índice de área foliar (IAF) son variables biofísicas relacionadas estrechamente con la tasa de evapotranspiración de los cultivos y su producción de biomasa. A pesar de su importancia, usualmente no se miden de manera directa debido al tiempo invertido y costo; sin embargo, se pueden estimar a gran escala y en tiempo casi real mediante información espectral captada en imágenes de satélite, pero esto requiere de su validación a nivel de campo. Se desarrollaron y validaron modelos de regresión lineal simple utilizando 13 índices de vegetación (IV) relacionados con el IAF y la FCV en alfalfa (Medicago sativa). Se usaron tres fuentes de información espectral: (i) La reflectancia para derivar los IV; (ii) fotografías digitales procesadas con Canopeo para estimar la FCV; y (iii) mediciones del IAF utilizando un ceptómetro. Se realizaron seis muestreos de campo entre marzo y junio de 2020, en cuatro parcelas de alfalfa situadas en Palmar de Bravo, Puebla, México. Para evaluar cada IV, se utilizó el coeficiente de determinación (R2) y la raíz del cuadrado medio del error (RCME). Se encontró que el IV más apropiado para estimar la FCV fue el VIgreen (Green Vegetation Index, R2 = 0.987 y RCME = 0.093). En el caso del IAF, el IV que presentó el mejor desempeño fue el Normalized Difference Vegetation Index (NDVI), R2 = 0.935 y RCME = 0.746). Los resultados mostraron la aptitud y utilidad práctica de la información espectral para estimar las variables biofísicas en el cultivo de alfalfa y su monitoreo.

Summary: Carya illinoinensis (Wangenh.) K. Koch is a fruit tree with high economic value. However, this crop is very sensitive to zinc (Zn) deficiency in alkaline soils, where an alternative to minimize this problem is the edaphic supply of this micronutrient. Thus, the objective of this research is to evaluate the response of some physiological variables (trunk diameter, fruiting shoot length, terminal leaflet area and leaf Zn concentration), yield components (kg tree-1, nut weight, kernel percentage and alternation index) to the edaphic Zn chelate application in pecan nut “Western Schley” for three years in Chihuahua, Mexico. Five edaphic doses of Zn chelate (Carboxy Zn®, Innovak Global, México kg ha-1) T1 (8.5), T2 (17), T3 (34), T4 (51), T5 (68), where T0 corresponds to the control (no application) were evaluated in a split-plot experimental design with five replications. Statistical analyses showed statistical differences in physiological parameters such as trunk diameter and shoot length (19.93 and 19.27 cm, respectively), terminal leaflet area (34.08 cm2) and leaf Zn concentration (34.93 mg kg-1) with soil application of 8.1 (kg ha-1 of Carboxy Zn), as well as yield components (12.82 kg tree-1, 7.82 g nut weight and 59.15 kernel percentage) and minimize the bearing alternation index. The edaphic application of Carboxy Zn could be an alternative to Zn supply in the agronomic management of commercial pecan nut orchards in alkaline soils.

Resumen: Carya illinoinensis (Wangenh.) K. Koch., es un frutal con alto valor económico, sin embargo, es un cultivo muy sensible a la deficiencia de zinc (Zn) en suelos alcalinos, donde una alternativa para minizar este problema es el suministro edáfico de este micronutriente. El objetivo de esta investigación fue evaluar la respuesta de variables fisiológicas (diámetro de tronco, longitud de brote fructífero, área del foliolo terminal y concentración foliar de Zn) y componentes de rendimiento (kg árbol-1, peso de la nuez, porcentaje de la almendra e índice de alternancia), a la aplicación de quelato de Zn en nogal pecanero “Western Schley”. Durante tres años en Chihuahua, México, se evaluaron cinco dosis edáficas de quelato Zn (Carboxy Zn®, Innovak Global) en kg ha-1 de los siguientes tratamientos: T1 (8.5), T2 (17), T3 (34), T4 (51), T5 (68), donde T0 corresponde al testigo (sin aplicación) en un diseño experimental de parcelas dividas con 5 repeticiones. El análisis estadístico reflejó diferencias estadísticas con la aplicación edáfica de 8.1 (kg ha-1 de Carboxy Zn) en parámetros fisiológicos como diámetro de tronco y longitud de brote (19.93 y 19.27 cm respectivamente), área del folíolo terminal (34.08 cm2) y concentración foliar de Zn (34.93 mg kg-1). Así como los componentes de rendimiento (12.82 kilogramos fruto árbol-1, 7.82 g peso de la nuez y 59.15 porcentaje de la almendra) y minimizarón el índice de alternancia. La aplicación edáfica de Carboxy Zn, podría ser una alternativa al suministro de Zn en el manejo agronómico de huertos comerciales de nogal pecanero en suelos alcalinos.

Resumen La cuenca baja del río Acre se ubica en una zona de deforestación con la implementación de pastizales para ganado vacuno en suelos susceptibles a la erosión y clima ecuatorial. La existencia de mataderos y ganado vacuno en el municipio de Boca do Acre, en el estado de Amazonas, es uno de los problemas vinculados a la deforestación en la Amazonía brasileña. Ante este escenario, se presentó una estimación de las pérdidas de suelo con la aplicación de la Ecuación Universal en un sistema de información geográfica. En la metodología, se desarrolló una base de datos con información vectorizada para extraer las áreas de tipos de suelo y cobertura del suelo, incluyendo el análisis espacial de pendientes extraído del modelo digital de elevación. Como resultado del análisis de las áreas por geoprocesamiento y vectorización, se obtuvieron los cálculos de las parcelas de erosión a través de tablas con los parámetros adoptados por los referentes científicos. Se encontró que el 60% de la pérdida de suelo ocurre en el área agrícola en el 11% del territorio de la cuenca, siendo predominantemente en áreas de asentamientos rurales en el estado de Acre. Como resultado de la estimación, la pérdida de suelo en la cuenca baja del río Acre fue de 386.422 t/ha/año, con una producción de 46 millones de toneladas de sedimentos por año.

Abstract The Lower Acre River Basin is located in an area of deforestation with the implementation of pastures for beef cattle ranching in soils susceptible to erosion and equatorial climate. The existence of slaughterhouses and beef cattle in the municipality of Boca do Acre, in the state of Amazonas, is one of the problems linked to deforestation in the Brazilian Amazon. Given this scenario, an estimate of soil losses was presented with the application of the Universal Equation in a geographic information system. In the methodology, a database was elaborated with vectorized information for the extraction of the areas of the types of soils and land cover, including the spatial analysis of slopes extracted from the digital elevation model. Due to the analysis of the areas by geoprocessing occurring by vectorization, the calculations of the erosion plots were obtained through tables with the parameters adopted by the scientific references. It was found that 60% of the soil loss occurs in the area of agriculture in 11% of the territory of the watershed, being predominantly in areas of rural settlements of the state of Acre. As a result of the estimate, soil loss in the Lower Acre River Basin was 386,422 t/ha/year, with a production of 46 million tons of sediment per year.

Resumo A Bacia do Baixo Rio Acre está localizada em uma área de desflorestamento com implantação de pastagens para pecuária de corte em solos suscetíveis à erosão e clima equatorial. A existência de abatedouros e pecuária de corte implantada no município de Boca do Acre, no Amazonas, é um dos problemas vinculados ao desmatamento da Amazônia Brasileira. Diante desse cenário, foi apresentada uma estimativa de perdas de solo com aplicação da Equação Universal em sistema de informação geográfica. Na metodologia, foi elaborado um banco de dados com informações vetorizadas para extração das áreas dos tipos de solos e cobertura da terra, incluindo a análise espacial de declividades extraídas do modelo digital de elevação. Em decorrência da análise das áreas pelo geoprocessamento ocorrer pela vetorização, foram obtidos os cálculos das parcelas de erosão através de tabelas com os parâmetros adotados pelas referências científicas. Foi constatado que 60% da perda de solo ocorrem na área de agricultura em 11% do território da bacia hidrográfica, sendo predominantemente em áreas de assentamentos rurais do estado do Acre. Como resultado da estimativa, a perda de solos na Bacia do Baixo Rio Acre foi de 386.422 t/ha/ano, com uma produção de 46 milhões de toneladas de sedimentos por ano.

Resumen. Los datos de campo obtenidos de los inventarios forestales, principalmente área basal y densidad de fustes, son relevantes para el análisis de la biomasa aérea y la fragmentación forestal. Debido al suelo inundado, el trabajo de campo en los bosques de manglar requiere mucho tiempo y es complicado. Dado que los manglares son sensibles a los efectos del cambio climático, la selección de un método de campo ideal es de suma importancia. Con este fin, analizamos 4 clases de manglares: Rhizophora mangle (RM), Laguncularia racemosa (LR), Avicennia germinans (AG) y AG arbustivo. Georreferenciamos y contamos todos los fustes de mangle dentro de 4 parcelas cuadradas de 0.04 ha (20 × 20 m). Analizamos 3 áreas circulares y el método del punto cuadrante central (PCQM) basado en las parcelas cuadradas originales. Dependiendo de la clase de mangle, el PCQM sobreestimó el área basal hasta en un 34% y la densidad de fustes en un 21%. Los 3 muestreos en parcelas circulares subestimaron el área basal entre -1% y -29% y la densidad de fustes entre -3% y -25%. Basándonos en los resultados, sugerimos utilizar una parcela circular de 0.04 ha (r = 11.28 m) en bosques menos densos (RM y AG) y una parcela circular de 0.015 ha (r = 6.9 m) en densidades superiores a 3,500 fustes/ha (LR y AG arbustivo). Las ventajas de utilizar las parcelas circulares sobre el método PCQM son que los inventarios de mangle pueden cuantificarse rápidamente y no requieren un número mínimo de puntos de muestreo.

Abstract. The data obtained from field-based forest inventories, mainly basal area and stem density, are relevant for the analysis of aboveground biomass and forest fragmentation. Due to its persistently flooded ground, fieldwork in mangrove forests is time-consuming and complicated. Since mangroves are sensitive to the effects of climate change, selecting a reliable field method is of utmost importance. To this end, we analyzed 4 mangrove classes: Rhizophora mangle (RM), Laguncularia racemosa (LR), Avicennia germinans (AG), and AG shrub. We georeferenced and counted all mangrove stems within four 0.04 ha (20 × 20 m square). We analyzed data from 3 circular area plots and the plotless point-centered quarter method (PCQM) based on the original square plots. Depending on the mangrove class, PCQM overestimated basal area by up to 34% and stem density by 21%. The 3 circular plot surveys underestimated basal area from -1% to -29% and stem density from -3 to -25%. Based on the results, we suggest using a circular plot of 0.04 ha (r = 11.28 m) in less dense forests (RM and AG) and a circular plot of 0.015 ha (r = 6.9 m) with forest densities greater than 3,500 stems/ha (LR and AG shrub). The advantages of using the circular plot approach over PCQM are that mangrove inventories can be quantified quickly and do not require a minimum number of sampling points.

Abstract Introduction: Evidence suggests that herbivores, such as peccaries, shape vegetation structure and diversity through predation, trampling, dispersal, and rooting behavior. Objective: To evaluate the impact of peccaries (Dycotiles tajacu) on the understory vegetation of the tropical rainforest in the Nogal-La Selva Local Biological Corridor, Costa Rica, comparing a site with the absence of peccaries to another with the presence of these animals. Methodology: From June to November 2021, 20 experimental exclusions and 20 free access plots, each measuring 2 m2 were used to quantify herbivory, the number of leaf blades, damaged leaves, healthy leaves, sapling height, and fallen biomass at both sites. Results: A higher sapling density was found in the Nogal Reserve, but a lower sapling diversity, while in La Selva there was a higher sapling diversity, but a lower density of seedlings. Herbivory and sapling height in La Selva exceeded those in Nogal. The exclusion of peccaries reduced seedling damage but did not affect the dynamics of fallen biomass. Conclusion: For the design, implementation, and evaluation of the effectiveness of biological corridors, it is crucial to consider plant-animal interactions to enhance the flow of ecological processes through functional and structural connectivity, analyzed from interactions such as those presented in this paper.

Resumen Introducción: Existe evidencia que herbívoros, como los saínos, dan forma a la estructura y diversidad de la vegetación a través del comportamiento de depredación, pisoteo, dispersión y enraizamiento. Objetivo: Evaluar el impacto de los saínos (Dycotiles tajacu) en la vegetación del sotobosque del bosque tropical húmedo en el Corredor Biológico Local Nogal-La Selva, Costa Rica, en un sitio con ausencia y en otro con presencia de saínos. Métodos: De junio a noviembre de 2021 se utilizaron 20 exclusiones experimentales y 20 parcelas de acceso libre de 2 m2, se cuantifico la herbivoría, número de láminas foliares, hojas dañadas, hojas sanas, altura de brinzales y biomasa caída en ambos sitios. Resultados: Se encontró una mayor densidad de brinzales en Reserva Nogal pero una menor diversidad, contrario en La Selva donde se encontró una mayor diversidad de brinzales, pero una menor densidad de plántulas. La herbivoría y la altura de brinzales en La Selva fue mayor que en Nogal. La exclusión de los saínos disminuyó el daño a las plántulas, pero no afectó la dinámica de la biomasa caída. Conclusión: Es necesario contemplar para el diseño, implementación y evaluación de la efectividad de corredores biológicos, las interacciones planta-animal, para potencializar el flujo de procesos ecológicos mediante la conectividad funcional y estructural, analizada a partir de interacciones como las presentadas en este trabajo.

Abstract Introduction: The use of arthropods in ecological studies in the tropical dry forest (TDF) of Colombia focused mainly on spiders, butterflies, ants, and dung beetles; therefore, it is necessary to understand the seasonal dynamics of the other groups such as Geadephaga in this ecosystem. Objective: To evaluate the spatio-temporal variations and the effect of environmental conditions on the diversity of the Geadephaga communities in two TDF fragments in the Colombian Caribbean. Methods: This study was conducted during four sampling events between February and June 2018, each lasting four days, and four nights. Four sampling stations were selected in each locality (Reserva Campesina La Montaña = RCM and Reserva La Flecha = RLF), separated 350 m one from another, with square plots of 50 × 50 m. A light trap was installed in the center of each square, while pitfall traps were installed in the four vertices, and manual capture, beating sheets and leaf litter sieve were carried out. Results: A total of 348 Carabidae and 114 of Cicindelidae were captured. In both fragments, the richness and abundance presented the lowest values in dry season, while the highest values were observed during the rainy season. Tetracha affinis (Dejean, 1825) was the most abundant species in RCM during rainy season. Conclusions: The richness variation and abundance of Geadephaga corresponds to a seasonal pattern at both locations. A high dissimilarity between the communities of Geadephaga from the two fragments was found, despite having similar environmental conditions.

Resumen Introducción: El uso de artrópodos en estudios ecológicos en el bosque seco tropical (Bs-T) de Colombia se centra mayormente en arañas, mariposas, hormigas y escarabajos coprófagos; por lo tanto, es necesario comprender como es la dinámica estacional de otros grupos como Geadephaga en este ecosistema. Objetivo: Evaluar la variación espacio-temporal y el efecto de las condiciones ambientales sobre la diversidad de las comunidades de Geadephaga en dos fragmentos de Bs-T en el Caribe colombiano. Métodos: El estudio se llevó a cabo en cuatro eventos de muestreo entre febrero y junio de 2018; cada uno con una duración de cuatro días y cuatro noches. En cada localidad (Reserva Campesina La Montaña = RCM y Reserva La Flecha = RLF), se marcaron cuatro estaciones distanciadas 350 m, con parcelas de 50×50 m. En el centro de cada parcela se instaló una trampa de luz, mientras que en los cuatro vértices se instalaron trampas de caída, y se realizó captura manual, cernido de hojarasca y perturbación de follaje. Resultados: Se capturó un total de 348 ejemplares de Carabidae y 114 de Cicindelidae. La riqueza y la abundancia presentaron los valores más bajos durante el período seco, mientras que los mayores valores se observaron durante el período de lluvias, en ambos fragmentos. Tetracha affinis (Dejean, 1825) fue la especie más abundante en la RCM durante el período lluvioso. Conclusiones: La variación de la riqueza y abundancia de Geadephaga responde a un patrón estacional en ambos fragmentos. Se encontró una amplia disimilitud entre las comunidades de Geadephaga de ambos fragmentos, pese a tener condiciones ambientales parecidas.

Abstract Introduction: Recent ecological studies have found a positive correlation between habitat structure and animal communities that inhabit them. Generally, such studies try to test the hypotheses that animal species diversity increases in complex and heterogeneous habitats since they may provide more potential niches that structurally simpler habitats. Objective: In this research, the effect of habitat complexity and heterogeneity, and structural habitat characteristics on the butterfly community (Papilionoidea) inhabiting three vegetation covers (shrubs, highland forest and paramo) was evaluated in high-montane ecosystems of the Central Cordillera, Antioquia department, Colombia. Methods: From January to July 2012, butterflies were systematically sampled using Van Someren Rydon traps. Simultaneously, complexity, heterogeneity, and vegetation structure were quantified using 0.04 ha circular plots established around the traps. Results: We reported 108 species, 48 genus and five families of butterflies. Butterfly richness and abundance were sensible to both complexity and heterogeneity of the vegetation covers, as well as to changes in the vegetation structure, showing strong correlations with habitat characteristics. Butterfly diversity was highest in the shrub habitat (1D = 25.02; 2D = 11.97), followed by the highland forest (1D = 15.83; 2D = 9.42) and paramo (1D = 12.36; 2D = 7.86). Moreover, richness and abundance of butterfly species were positively associated with the increase in canopy cover and vegetation density in horizontal and vertical strata. Conclusion: These findings underline the importance of preserving the heterogeneity of habitats and vegetation structure in the Andean high-montane ecosystems to maintain the diversity and abundance of butterflies, highlighting the need for conservation and management policies that consider the complexity and diversity of these ecosystems.

Resumen Introducción: Recientes investigaciones han mostrado correlaciones positivas entre la estructura del hábitat y las comunidades animales que los habitan. Generalmente, estos estudios evalúan la hipótesis de una mayor diversidad de animales en hábitats complejos y heterogéneos, ya que éstos pueden ofrecer un mayor número de nichos potenciales a diferencia de aquellos estructuralmente más simples. Objetivo: Se evaluó el efecto de la complejidad, la heterogeneidad y la estructura del hábitat sobre una comunidad de mariposas diurnas (Papilionoidea) en tres tipos de coberturas vegetales (rastrojo, bosque y páramo) ubicadas en ecosistemas de alta montaña sobre la cordillera Central, departamento de Antioquia, Colombia. Métodos: Entre enero y julio del 2012, se realizaron capturas de mariposas utilizando trampas Van Someren Rydon y se cuantificó la complejidad, la heterogeneidad y la estructura de la vegetación a partir de parcelas circulares de 0.04 ha establecidas alrededor de las trampas. Resultados: Se reportó un total de 108 especies, 48 géneros y cinco familias de mariposas. La riqueza y la abundancia de especies de mariposas fueron sensibles tanto a la complejidad y heterogeneidad de las coberturas vegetales como a los cambios en la estructura de la vegetación, mostrando fuertes correlaciones con las características del hábitat. El rastrojo presentó la mayor diversidad de mariposas (1D = 25.02; 2D = 11.97), seguido por el bosque (1D = 15.83; 2D = 9.42) y el páramo (1D = 12.36; 2D = 7.86). Adicionalmente, la riqueza y abundancia de mariposas se asoció positivamente con la cobertura de dosel y la densidad de vegetación de los estratos verticales y horizontales. Conclusión: Estos resultados subrayan la importancia de conservar la heterogeneidad de los hábitats y la estructura vegetal en los ecosistemas de alta montaña andinos, para mantener la diversidad y abundancia de las mariposas, resaltando la necesidad de políticas de conservación y manejo que consideren la complejidad y diversidad de estos ecosistemas.

Abstract Introduction: Mining is one of the main drivers of deforestation of tropical forests. This activity affects the storage of aboveground biomass of these ecosystems; therefore, their ability to contribute to the mitigation of global climate change. Objective: To assess the influence of soil properties on the aboveground biomass storage of post-mining forests in the Colombian Pacific. Methods: Plots were established in areas post-mining and with different successional ages (12-15 years, 30-35 years, and mature forest). The aboveground biomass and physicochemical parameters of the soil were measured. Results: An aboveground biomass of 15.58 t ha-1, 35.17 t ha-1, and 178.32 t ha-1 was recorded at 12-15 years, 30-35 years, and mature forests, respectively. The species with the highest biomass content in post-mining forests were Cespedesia spathulata and Clidemia septuplinervia. The aboveground biomass was positively correlated with organic matter (OM), calcium (Ca), magnesium (Mg), CICE, total nitrogen (N), and silt. In contrast, the relationship was negative with sand, aluminum (Al), and potassium (K) content. It was evidenced that the relationship between aboveground biomass and soils differed in each successional age. When evaluating the changes of aboveground biomass and soils in the succession, it was observed that the aboveground biomass and total N increased with the recovery time. At the same time, the P and K decreased with succession. On the other hand, the contents of OM, Mg, Al, Ca, and CICE showed curvilinear tendencies since they increased in the first stages and then decreased in the advanced successional stages. Conclusions: Aboveground biomass increases with forest recovery time in the study area. This increase is influenced by the presence of two dominant species shared among the investigated ecosystems and by the soil’s N, P, and K content.

Resumen Introducción: La minería es una de las principales causas de deforestación de los bosques tropicales. Esta actividad afecta el almacenamiento de biomasa aérea de estos ecosistemas; y, por tanto, su capacidad para contribuir a la mitigación del cambio climático global. Objetivo: Evaluar la influencia de las propiedades del suelo en el almacenamiento de la biomasa aérea de bosques post-minería del Pacífico colombiano. Métodos: Se establecieron parcelas en áreas post-minería con diferentes edades de sucesión (12-15 años, 30-35 años y bosque maduro). Se midió la biomasa aérea y parámetros fisicoquímicos del suelo. Resultados: Se registró una biomasa aérea de 15.58 t ha-1, 35.17 t ha-1 y 178.32 t ha-1 en 12-15 años, 30-35 años y bosque maduro, respectivamente. Las especies con mayor contenido de biomasa en los bosques post-minería fueron Cespedesia spathulata y Clidemia septuplinervia. La biomasa aérea se correlacionó positivamente con la materia orgánica (MO), calcio (Ca), magnesio (Mg), CICE, nitrógeno total (N) y limo. Por el contrario, la relación fue negativa con el contenido de arena, aluminio (Al) y potasio (K). Se evidenció que la relación entre la biomasa aérea y los suelos difería en cada edad sucesional. Al evaluar los cambios de la biomasa aérea y los suelos en la sucesión, se observó que la biomasa aérea y el N total aumentaron con el tiempo de recuperación. Al mismo tiempo, el P y el K disminuyeron con la sucesión. Por otro lado, los contenidos de OM, Mg, Al, Ca, y CICE mostraron tendencias curvilíneas ya que aumentaron en los primeros estadios y luego disminuyeron en los estadios sucesionales avanzados. Conclusiones: la biomasa aérea aumenta con el tiempo de recuperación del bosque en el área de estudio. Este incremento está influenciado por la presencia de dos especies dominantes compartidas entre los ecosistemas investigados y por el contenido de N, P y K del suelo.

ABSTRACT Potassium is a nutrient with the potential to increase plant tolerance to salt stress. The aim of this study was to evaluate the production and quality of kale subjected to salt stress and potassium concentrations in a protected environment. The experimental design was in split plots, with plots composed of five nutrient solutions (control treatment, S1 - standard nutrient solution prepared in low-salinity water, 0.5 dS m-1 (500 mg L-1 of KNO3), and four nutrient solutions prepared in brackish waters (3.5 dS m-1) containing four concentrations of KNO3 (S2 - 500 mg L-1, S3 - 625 mg L-1, S4 - 750 mg L-1, S5 - 1,000 mg L-1), and subplots represented by two leaf kale cultivars (Manteiga and Manteiga da Geórgia). Leaf production variables and post-harvest physical and chemical qualities were evaluated. The saline nutrient solution with the addition of NaCl (S2) reduced production but did not reduce the post-harvest quality of kale. The extra addition of KNO3 at 25% (S3) was efficient in reducing the deleterious effects of salt stress on the variables leaf length, leaf area, leaf production, and number of bunches. The cv. Manteiga da Geórgia was more tolerant to salt stress than the cv. Manteiga. environment control treatment S lowsalinity low salinity water 05 0 5 0. m1 m 1 m- (50 L1 L L- KNO3, KNO , KNO3) 3.5 35 3 (3. S2 (S 50 L1, 1, 62 75 1000 000 1,00 L-1) Geórgia. . Geórgia) postharvest post harvest evaluated 25 (S3 length area bunches cv (5 3. (3 6 7 100 00 1,0 2 ( 10

RESUMO O potássio é um nutriente com potencial para aumentar a tolerância das plantas ao estresse salino. O objetivo deste estudo foi avaliar a produção e a qualidade da couve submetida ao estresse salino e às concentrações de potássio em ambiente protegido. O delineamento experimental adotado foi em parcela subdivididas, sendo as parcelas compostas por cinco soluções nutritivas (tratamento controle, S1 - solução nutritiva padrão usando água de baixa salinidade, 0,5 dS m-1 (500 mg L-1 de KNO3), e quatro soluções nutritivas preparadas em águas salobras (3,5 dS m-1) contendo quatro concentrações de KNO3 (S2 - 500 mg L-1, S3 - 625 mg L-1, S4 - 750 mg L-1, S5 - 1.000 mg L-1). As subparcelas foram representadas por duas cultivares de couve folha (Manteiga e Manteiga da Geórgia). Foram avaliadas as variáveis de produção de folhas e qualidades físicas e químicas pós-colheita. A solução nutritiva salinizada com adição de NaCl (S2) reduziu a produção, mas não reduziu a qualidade pós-colheita da couve folha. A adição extra de KNO3 em 25% (S3) foi eficiente para reduzir o efeito deletério do estresse salino sobre as variáveis comprimento de folha, área foliar, produção e número de maços. A cv. Manteiga da Geórgia se mostrou mais tolerante ao estresse salino que a cv. Manteiga. protegido subdivididas tratamento controle S salinidade 05 0 5 0, m1 m 1 m- (50 L1 L L- KNO3, KNO , KNO3) 3,5 35 3 (3, S2 (S 50 L1, 1, 62 75 1000 000 1.00 L1. . L-1) Geórgia. Geórgia) póscolheita. póscolheita pós colheita. colheita 25 (S3 foliar maços cv (5 3, (3 6 7 100 00 1.0 2 ( 10 1.

ABSTRACT Storage is one of the main stages during grain production. The present study was conducted to evaluate the use of silo bags as an alternative for storing landrace cowpea grains. The experiment used samples of the Arigozinho, Manteiguinha, and Quarentão cowpea varieties from Cruzeiro do Sul - Acre, harvested in the 2021 crop season. The samples (500 g) were stored in raffia and silo bags for 30, 60, 90, and 120 days. The experimental design was completely randomized, arranged in a split-plot-in-time scheme (2 × 5) with four replicates. Storage conditions represented the plots: silo bags and raffia bags. The subplots comprised five storage conditions: 0, 30, 60, 90, and 120 days for each landrace cowpea variety. The insect species identified in all varieties was Zabrotes subfasciatus, with infestation ranging from 49% to 98% in raffia bags and less than 10% in silo bags over 120 days. A depreciation in grain quality was observed during storage in raffia bags. There was increase in electrical conductivity, fluctuations in water content, and reductions in bulk density and germination due to the higher degree of infestation in all the investigated varieties. The grains stored in silo bags showed minimal variations over the 120 days, maintaining their initial quality throughout the storage period. The bag silo storage system is an effective alternative for controlling Z. subfasciatus and maintaining the grain quality of the varieties Arigozinho, Manteiguinha, and Quarentão for a period of up to 120 days. production Arigozinho Manteiguinha Acre 202 season 500 (50 g 30 60 90 12 randomized splitplotintime split plot time 2 ( 5 replicates plots 0 variety 49 98 10 conductivity content Z 20 50 (5 3 6 9 1 4

RESUMO O armazenamento é uma etapa crucial durante a produção de grãos. Este trabalho foi realizado com o objetivo de avaliar o uso de silo bolsa como alternativa no armazenamento de grãos crioulos de feijão-caupi. Para o estudo utilizou-se amostras de feijão-caupi, das variedades Arigozinho, Manteiguinha e Quarentão, procedentes do município de Cruzeiro do Sul - Acre, safra 2021. As amostras de 500 g foram armazenadas em silos bolsa e sacos de ráfia, durante 30, 60, 90, 120 dias. O experimento foi inteiramente casualizado, com parcelas subdivididas no tempo (2 × 5), com quatro repetições. As parcelas foram as condições de armazenamento: silo bolsa e sacos de ráfia, e as subparcelas, os períodos de armazenamento: 0, 30, 60, 90 e 120 dias para cada variedade crioula de feijão-caupi. Zabrotes subfasciatus foi identificado em todas as variedades, com infestações de 49 a 98% em sacos de ráfia e inferiores a 10% em silo bolsa ao longo de 120 dias. Foi observado a depreciação na qualidade dos grãos durante o período de armazenamento em sacos de ráfia. Houve aumento na condutividade elétrica, flutuações no teor de água, redução da massa específica aparente e na germinação, devido ao maior grau de infestação em todas as variedades investigadas. Os grãos em silo bolsa apresentaram mínimas variações e mantiveram a qualidade inicial durante 120 dias. O armazenamento em silo bolsa é eficaz no controle de Z. subfasciatus e na manutenção da qualidade dos grãos das variedades Arigozinho, Manteiguinha e Quarentão por até 120 dias. feijãocaupi. feijãocaupi feijão caupi. caupi feijão-caupi utilizouse utilizou se feijãocaupi, caupi, Arigozinho Acre 2021 50 30 60 12 casualizado 2 ( 5, 5 , 5) repetições subparcelas 0 9 4 98 10 elétrica água germinação investigadas Z 202 3 6 1 20