Hydropedological behavior of a chromic vertisol under different plant covers

Vertisols present edaphic limiting factors primarily of a physical nature. The study of their hydropedology, supported by multivariate techniques, is of vital importance. The work was developed with the objective of determining, through multivariate analysis, the hydropedological behavior of a Chromic Vertisol under different plant covers. In areas under natural grass, sugarcane, and secondary forest, belonging to the Holguín Sugarcane Provincial Research Station, three random points were chosen in each. Soil penetration resistance, soil bulk density, gravimetric moisture, and volumetric moisture at depths of 0-10, 10-20 and 20-30cm were determined. A Principal Component Analysis and Canonical Correlations were performed using Statistica 7 and Statgraphics Plus XV.II. The first two components made the greatest contribution to the variance, with 83.09%. The greatest contributions (1st component) were given by moisture at all depths and by soil compaction at a depth of 20-30 cm. The 2nd component was influenced by soil compaction in the 0-10 and 10-20cm layers. There was a contrast between the variables that characterize the solid phase with which they describe the liquid phase of the soil. There was a correlation between soil moisture and compaction. The first two pairs of canonical variables showed a strong linear correlation and regularly dispersed along the central values of the model, with a remarkable grouping by depths

Chemical Properties that Determine Boron Availability in Sugar Cane Soils

Context: Several factors are limiting the behavior and dynamics of boron (B) in the soil. Few results on assimilable B contents in the soil and its relation to other chemical properties have been published. Objective: To determine the contents of assimilable B and the chemical properties that condition its availability in three of the main soil types where sugar cane is cultivated. Methods: The samples were taken at random from the surface (0-20 cm) of three of the main soil types where sugar cane is cultivated in Cuba. Soil assimilable B was determined by extraction with hot water. Classification of assimilable boron concentration relied on category ranges set up by Agrolab, (2005): low (˂0.5 mg kg-1), mid (0.5 a 2.0 mg kg-1), and high (˃2.0 mg kg-1). Results: The concentration of assimilable B varied according to the soil type, with a high dependence on chemical properties. Conclusions: The B contents was highly dependent on variables K2O, P2O5, Mg+ and Na+. The average B concentration was within mid-range values in vertisols and low in brown and ferralitic soils, with high variability. The contents of assimilable B should be further studied, along with the effect of limiting chemical, physical, and biological factors on the soil

Propiedades químicas que determinan la disponibilidad de boro en suelos cultivados con caña de azúcar

Context: Several factors are limiting the behavior and dynamics of boron (B) in the soil, though in Cuba, few results on available B contents in the soil and its relation to other chemical properties have been published. Objective: To determine the contents of available B and the chemical properties that condition its availability in three of the main soil types where sugar cane is cultivated. Methods: The samples were taken at random from the surface (0-20 cm) of three of the main soil types where sugar cane is cultivated in Cuba. The available B in the soil was determined by extraction with hot water. Classification of available boron concentration relied on category ranges set up by Agrolab, (2005): low (˂0.5 mg kg-1), mid (0.5 a 2.0 mg kg-1), and high (˃2.0 mg kg-1). Results: The concentration of assimilable B varied according to the soil type, with a high dependence on chemical properties. Conclusions: The B content was highly dependent on variables K2O, P2O5, Mg+ and Na+. The average B concentration was within mid-range values in vertisols and low in brown and ferralitic soils, with high variability. The contents of available B should be further studied, along with the limiting effects of chemical, physical, and biological factors on the soil.Contexto: Varios factores limitan el comportamiento y la dinámica del boro (B) en el suelo y en Cuba existen escasos resultados sobre el contenido de B asimilable en el suelo y su relación con otras propiedades químicas. Objetivo: Determinar el contenido de B asimilable y las propiedades químicas que condicionan su disponibilidad en tres de los principales agrupamientos de suelos donde se cultiva la caña de azúcar. Métodos: Las muestras fueron tomadas al azar en el horizonte superficial (0-20 cm) de tres de los principales agrupamientos de suelos donde se cultiva la caña de azúcar en el país. El B asimilable en el suelo se determinó mediante extracción con agua caliente. Para clasificar la concentración de boro asimilable en suelo se utilizó los rangos de categorías establecidos por Agrolab, (2005): bajo (˂0.5 mg kg-1), medio (0.5 a 2.0 mg kg-1) y alto (˃2.0 mg kg-1). Resultados: La concentración de B asimilable difiere por agrupamientos de suelo con una alta dependencia de las propiedades químicas. Conclusiones: El contenido de B tuvo una alta dependencia de las variables K2O, P2O5, Mg+ y Na+. La concentración promedio de B se encontró dentro del rango medio de disponibilidad en Vertisoles y bajo en los Pardos y Ferralíticos, con una alta variabilidad. Se recomienda continuar estudiando el contenido de B asimilable y el efecto de los factores limitantes, químicos, físicos y biológicos sobre su comportamiento en el suelo

Hydropedological behavior of a chromic vertisol under different plant covers

Vertisols present edaphic limiting factors primarily of a physical nature. The study of their hydropedology, supported by multivariate techniques, is of vital importance. The work was developed with the objective of determining, through multivariate analysis, the hydropedological behavior of a Chromic Vertisol under different plant covers. In areas under natural grass, sugarcane, and secondary forest, belonging to the Holguín Sugarcane Provincial Research Station, three random points were chosen in each. Soil penetration resistance, soil bulk density, gravimetric moisture, and volumetric moisture at depths of 0-10, 10-20 and 20-30cm were determined. A Principal Component Analysis and Canonical Correlations were performed using Statistica 7 and Statgraphics Plus XV.II. The first two components made the greatest contribution to the variance, with 83.09%. The greatest contributions (1st component) were given by moisture at all depths and by soil compaction at a depth of 20-30 cm. The 2nd component was influenced by soil compaction in the 0-10 and 10-20cm layers. There was a contrast between the variables that characterize the solid phase with which they describe the liquid phase of the soil. There was a correlation between soil moisture and compaction. The first two pairs of canonical variables showed a strong linear correlation and regularly dispersed along the central values of the model, with a remarkable grouping by depths.Los Vertisoles presentan factores edáficos limitantes fundamentalmente de carácter físico. El estudio de su hidropedología, apoyado en técnicas multivariadas, es de vital importancia. El trabajo se desarrolló con el objetivo de determinar, mediante análisis multivariado, el comportamiento hidropedológico de un Vertisol Crómico bajo diferentes usos de la tierra. En áreas bajo pasto natural, caña de azúcar y bosque secundario, pertenecientes a la Estación Provincial de Investigaciones de la Caña de Azúcar de Holguín, se escogieron tres puntos al azar en cada una. Se determinó la resistencia a la penetración, la densidad aparente, la humedad gravimétrica y la humedad volumétrica a las profundidades de 0-10, 10-20 y 20-30 cm. Se realizó un Análisis de Componentes Principales y de Correlaciones Canónicas, con los softwares Statistica 7 y Statgraphics Plus XV.II. Se encontró que las dos primeras componentes realizaron la mayor contribución a la varianza, con un 83.09%. Los mayores aportes (1ra componente) estuvieron dados por la humedad en todas las profundidades y por la compactación del suelo en la profundidad de 20-30 cm. La 2da componente estuvo influenciada por la compactación del suelo en las capas de 0-10 y de 10-20 cm. Existió contraposición entre las variables que caracterizan la fase sólida con las que describen la fase líquida del suelo. Existió correlación entre la humedad del suelo y la compactación. Los dos primeros pares de variables canónicas mostraron una fuerte correlación lineal y dispersada regularmente a lo largo de los valores centrales del modelo, con un notable agrupamiento por profundidades

Sensoramiento remoto del rendimiento agrícola en caña de azúcar en Cacocum, Cuba

The study was carried out in the 2021 year with the objective of estimating yield of sugarcane through the Normalized Difference Index of Vegetation in the "Cristino Naranjo" Sugar Company, located in the Cacocum municipality, Holguín province, Cuba. 32 randomized sample points were drawn in different months in which the images belonging to the Landsat 8 OLI/TIRS satellite projected in the WGS 84 UTM Zone 18 North system in grid 011/046 were chosen. The radiometric correction of each satellite image and the sampling scheme were carried out with the QGIS "A Coruña" software version 3.10. The value of each point was extracted with ArcGIS 10.5 after the calculation of the NDVI. For the statistical processing, Stargraphics Plus 5.0 software was used; in which, the linear regression analysis was carried out between the values obtained from the NDVI at each sampling point and the real yield values offered by specialists from the central analysis area that corresponds to the image data used. The determination of the NDVI vegetative index showed values from 0 to 0.5, equivalent to a low vegetation in the study area. The coefficient of determination indicates that the model explains 97.8598 of the yield variability in the sugarcane crop, which can be used as a mathematical model for estimating crop yield under the edaphoclimatic conditions of the study site.El estudio se realizó en el año 2021 con el objetivo de estimar el rendimiento agrícola de la caña de azúcar mediante el Índice de Diferencia Normalizado de Vegetación en la Empresa Azucarera “Cristino Naranjo”, ubicado en el municipio Cacocum provincia Holguín, Cuba. Se trazaron 32 puntos aleatorios de muestreo en los diferentes meses en los que se escogieron las imágenes pertenecientes al satélite Landsat 8 OLI/TIRS proyectadas en el sistema WGS 84 UTM Zona 18 Norte en la cuadrícula 011/046. En el software QGIS “A Coruña” versión 3.10 se realizó la corrección radiométrica de cada imagen satelital y el esquema de muestreo, mientras que en ArcGIS 10.5 se realizó la extracción de los valores de cada punto luego del cálculo del NDVI Para el procesamiento estadístico se utilizó el software Stargraphics Plus 5.0; en el cual se realizó el análisis de regresión lineal entre los valores obtenidos del NDVI en cada punto de muestreo y los valores del rendimiento real ofrecidos por especialistas del área de análisis del Central que se corresponden a las fechas de las imágenes utilizadas. La determinación del índice vegetativo NDVI muestra valores desde 0 hasta 0,5 se presenta una escasa vegetación en el área de estudio. El coeficiente de determinación indica que el modelo explica el 97,8598 de la variabilidad del rendimiento en el cultivo de la caña de azúcar lo cual puede ser utilizado como modelos matemáticos para la estimación del rendimiento de este cultivo bajo las condiciones edafoclimáticas del sitio de estudio

Multivariate analysis of the chemical properties of the eroded brown soils

The work was carried out with the data obtained of 30 profiles of Brown soils classified according to the effect of erosion. With the objective of determining, by means of a multivariate analysis, the effect of the erosion on the chemicals properties of the Brown soils was carried out a Discriminant and Principals Components Analysis. It was evaluated the chemicals variables pH in water, pH in KCl, organic matter, calcium, magnesium, potassium, sodium and S, T and V values. The Multivariate Analysis allowed establishing that magnesium is the only chemical property that evidence contraposition with the other variables, due to the harmful effect that this base exerts on the soil aggregates, which can accelerate or stressing the action of the erosive processes in the Brown soils. In the Principals Components Analysis, then components represented by the influence of the soil reaction, the absorbing complex and magnesium accumulate 78.75 % of the variance. The Discriminant Analysis explains the 97.06 % of the total of the variation in the two first axes, with the 93.33 % of good classification, with all the groups conformed by the categories of erosion well told apart among themselves

Dry matter and primary macroelements on the foliar biomass of sugarcane with different fertilizer rates of phosphorus

With the objective of determining the quantities of dry matter and primary macroelements on the foliar biomass of the sugar cane fertilized with different phosphorus rates was carried out a in an experiment in blocks at random (8 treatments x 6 replications) on a Chromic Vertisol. Five plants per plot at the 3rd replication and crop cycle were cut before harvesting. To the sugarcane top of the samples were determined the percentages of dry matter, nitrogen, phosphorus and potassium; was carried out a count of sugarcane stalk in each plot to express the percentages in magnitudes of mass.An Analysis of Variance of simple classification and the test of multiple status of Duncan to 95 % of probability was executed. The yearly fertilizations with 50 and 25 kg ha-1 of phosphorus from the 1rst cycle and the application at the start of a cycle of 125 kg ha-1 showed the bigger dry matter contents and the second ratoons had the biggest influence in the matter production. It was appreciated that the influence of the crop cycle was bigger than that rates of phosphorus on the dry matter content. The rate of phosphorus and the crop cycle with bigger content of primary macroelements were those where the dry matter was in bigger quantities. In the interaction rates of phosphorus-crop cycle the bigger contents of phosphorus and potassium was obtained on the 2nd ratoon with yearly and to the start of crop cycle applications of phosphorus

Análisis multivariado del efecto agrogénico del uso de la tierra sobre diferentes tipos de suelos

The changes that, in terms of land uses, man makes cause variations in the properties of soils. When the change is made for agri-cultural purposes, the fertility of the soil is deteriorated and the hydrological regime is altered. In order to determine, through a multivariate analysis, the agrogenic effect of land use on different types of soil, three permanent observation points were evaluated in Holguín province. The soils were Dark Red Ferritic, Chromic Vertisol and Pellic Vertisol, all with three uses of the land, sugarcane, natural grass and different forest variants (pines, neem and casuarinas). The soil bulk density and the average gravimetric moisture were determined, from three repetitions in each land use for the depths of 0-20, 20-40 and 40-60 cm. The Principal Component Analysis was used to identify the variables that explain the greater variability of the data and the Discriminant Analysis for the degree of accuracy of the groups and the differences between them. The greatest explanations for the variance were given by the physical properties in the lower horizons, which coincided with the main horizons of ferric and vertic diagnosis. The effect of these properties on the explanation of the variance was lower in the superficial horizon; what made us assume a greater difference between soil types than between land uses. However, the discriminant analysis showed highly significant differences between all the groups, with a correlation between them close to 1, with good discrimination and 85.19% of good classification.Los cambios que, en cuanto a usos de la tierra, el hombre realiza provocan variaciones en las propiedades de los suelos. Cuando el cambio se realiza con fines agrícolas se deteriora la fertilidad del suelo y se altera el régimen hidrológico. Con el objetivo de determinar, mediante un análisis multivariado, el efecto agrogénico del uso de la tierra sobre diferentes tipos de suelo, fueron evaluados tres puntos de observación permanentes en la provincia de Holguín. Los suelos fueron Ferrítico Rojo Oscuro, Vertisol Crómico y Vertisol Pélico, todos con tres usos de la tierra, caña de azúcar, pasto natural y diferentes variantes de bosque (pinos, neem y casuarinas). Se determinaron la densidad aparente y la humedad gravimétrica promedio, a partir de tres repeticiones en cada uso de la tierra para las profundidades de 0-20, 20-40 y 40-60 cm. Fue empleado el Análisis de Componentes Principales para identificar las variables que expliquen la mayor variabilidad de los datos y el Análisis Discriminante para el grado de exactitud de los grupos y las diferencias entre estos. Las mayores explicaciones de la varianza estuvieron dadas por las propiedades físicas en los horizontes inferiores, que coincidieron con los horizontes principales de diagnóstico férrico y vértico. El efecto de estas propiedades sobre la explicación de la varianza fue menor en el horizonte superficial; lo que hizo suponer una mayor diferencia entre tipo de suelos que entre usos de la tierra. Sin embargo, el análisis discriminante mostró diferencias altamente significativas entre todos los grupos, con una correlación entre ellos cercana a 1, con buena discriminación y un 85,19% de buena clasificación

Dry matter and primary macroelements on the foliar biomass of sugarcane with different fertilizer rates of phosphorus

The research consisted of determining the quantities of dry matter and primary macroelements on the foliar biomass that contributes to the soil the sugarcane fertilized with different fertilizer rates of potassium in an experiment with a design in complete blocks at random (8 treatments x 6 repetitions) on a Chromic Vertisol. Five plants were cut in the furrows 2 and 3 of the plots of the 3rd repetition before the harvest of each one of the four ratoons. To the sugarcane top of the samples were determined the percentages of dry matter, nitrogen, phosphorus and potassium; was carried out a count of sugarcane stalk in each plot to express the percentages in magnitudes of mass. An analysis of variance of simple classification was executed and means were compared by Duncan test at 95 % of confidence. The treatment V was the one of bigger dry matter content, with 11.04 t ha-1. The 2nd ratoon showed the bigger dry matter content in the sugarcane tops, with 11.13 t ha-1. In the interactions the bigger influence of the sugarcane stubble phase on the dry matter can be appreciated. The treatment V was the one of bigger nutrient content, with 83, 16 and 197 kg of NPK, respectively. In the case of nitrogen the best interaction was the treatment V in the 3rd ratoon, in the phosphorus also the treatment V in the 2nd and 3rd ratoons and the treatment IV in the 4th ratoon, in potassium the interaction of the treatment V in the 2nd ratoon

Comportamiento de las fracciones activas del fósforo inorgánico en los vertisoles crómicos de Holguín.

La investigación se realizó con la información de 40 perfiles de suelo de un vertisol crómico, en áreas cultivadas con caña de azúcar de la Empresa Azucarera Holguín. Se tomaron las determinaciones analíticas correspondientes a las fracciones activas del fósforo inorgánico (P-Ca, P-Fe, P-Al), P-total y el fósforo asimilable por el método de Oniani, a las profundidades 0-25, 25-50, 50-75 y 75-100 cm. Los resultados mostraron un bajo nivel del P- total con una progresiva disminución de la profundidad del perfil, P-Ca es la fracción dominante en estos suelos, lo que indica un bajo nivel de meteorización del perfil, P-Fe y P-Al a diferencia de P-Ca disminuyen con la profundidad. La relación de las fracciones activas con el pH, demostró que P-Ca aumenta, a medida que lo hace el pH, una relación inversa mostró el fósforo ligado a las fracciones (P-Fe y P-Al)