RESUMO
The importance of daily data on reference evapotranspiration (ET0) has increased in recent years due to its relevance in planning and decision making regarding irrigated agriculture, water production, and forest restoration. Facing the scarcity of this information measured in loco, the study of interpolation methods capable of representing ET0 becomes important. Therefore, this study aimed to evaluate the adequacy of the Random Forest (RF) method in the spatialization of ET0 in the watersheds of the Mid-South region of the Espírito Santo State, located within the Atlantic Forest biome, Brazil. From this study, it was found that the RF method is the most suitable one for ET0 spatialization when compared to the Angular distance weighting (ADW) and the inverse distance weighting (IDW) techniques. Also, the spatializations carried out by this method were transformed into databases in a grid format and made available online. Furthermore, the RF database was also compared to other ET0 grid databases, and it was concluded that the RF database also carried out a better performance than the other ones.
Assuntos
Produtos Agrícolas , Transpiração Vegetal , Ecossistema , Monitoramento Ambiental , TemperaturaRESUMO
Objetivou-se com este trabalho desenvolver um modelo matemático para estimar a massa do cacho (MC) de bananeira 'Prata Anã', utilizando características morfológicas das plantas. As equações de regressão linear múltiplas foram determinadas considerando-se a massa real do cacho (MC) como variável dependente e como variáveis independentes, a largura da terceira folha (LF), número de folhas (NF), diâmetro do cacho (DC) e número de bananas por cacho (NB). O modelo linear múltiplo de regressão que melhor estimou a massa do cacho da bananeira 'Prata Anã' ao nível de 5% de significância com R2 de 0,58 foi a equação, MC = -10,96 + 0,176*(DC) + 0,0983*(NB) + 0,0928*(LF) + 0,2216*(NF).
The objective of this work was to develop a mathematician model to estimate the mass of the bunch (MC) of banana cultivar Prata Anã, using dimensions of morphological characteristics of plants. The multiple linear regressions were determined considering the actual mass of the bunch (MC) as the dependent variable and independent variables as the width of the third leaf (LF), number of leaves at tree (NF), diameter of the bunch (DC) and number of bananas per bunch (NB). The multiple linear model that best estimated mass of the bunch to the banana 'Prata Anã' at 5% level of significance was 58% with R2 of the equation, MC = -10,96 + 0,176 * (DC) + 0,0983 * ( NB) + 0,0928 * (LF) + 0,2216 * (NC).
Assuntos
Modelos Lineares , MusaRESUMO
O conhecimento da variabilidade espacial dos atributos de um solo sob diferentes coberturas auxilia o estudo das alterações ocorridas em razão do manejo. O objetivo deste trabalho foi determinar, com uso da estatística clássica e geoestatística, a variabilidade espacial das frações texturais de um solo cultivado com pastagem e vegetação nativa. Amostras de solo foram coletadas na profundidade de 0-0,20m, nos pontos de cruzamento de uma malha, com intervalos regulares de 10m, totalizando 64 pontos em cada área. Na área de pastagem, as frações areia grossa e total apresentaram valores médios maiores em relação à vegetação nativa e correlações negativas com as altitudes dos pontos amostrais nas duas áreas. Todas as frações texturais apresentaram dependência espacial de moderada a alta nas duas áreas e com o patamar definido, com exceção da areia fina e do silte na pastagem. Grande parte dessa variabilidade ocorre em função da erosão hídrica.
The study of the spatial variability of soil attributes under different crop helps the study of changes due the management. This research was carried out to determine spatial variability the particle-size distribution, using of the classic statistic and geostatistics, of a soil cultivated with pasture and native vegetation. Soil samples were collected in the layer 0-0.20m, at the crossing points of a regular grid with 10m-intervals, summing up 64 samples points in each area. In the pasture area the fractions of coarse and total sand presented larger mean values in relation to the native vegetation, and negative correlation with the altitude of the points samples in the two areas. All of the fractions presented moderate to high spatial dependence in the two areas and with the defined still, with exception of the fine sand and the silt in the pasture. Much of this variability occurs as a function of water erosion.