O objetivo do trabalho foi avaliar as variáveis relacionadas à qualidade da pulverização e a distribuição espacial de taxas ótimas de aplicação em diferentes talhões para erradicação de brotações de eucalipto. O estudo foi conduzido em talhões de plantio de eucalipto, no município de Itabela-BA, em atividades de aplicação de herbicida pré-plantio, em áreas de reforma florestal. A aplicação foi realizada em diferentes talhões, sendo os mesmos considerados como unidades amostrais de diferentes tratamentos (T01, T02 e T03). A qualidade da aplicação foi avaliada a partir do estudo do espectro de gotas. Para isso, foram espalhadas etiquetas hidrossensíveis em seis plantas por tratamento, sendo amostradas nos terços inferior, médio e superior das brotações. Após a aplicação, as etiquetas foram analisadas em um programa computacional para determinação das variáveis número de gotas, dispersão de gotas, densidade de gotas, diâmetro de gotas, cobertura do alvo e volume de calda. Os dados foram submetidos à análise de variância em delineamento experimental de parcelas subdivididas no espaço e, em caso de significância pelo teste F, as médias de cada tratamento foram comparadas pelo teste de Tukey ao nível de 95% de probabilidade. Para avaliar a taxa de aplicação, foram construídos cenários de probabilidade de ocorrência utilizando o interpolador geoestatístico da krigagem indicativa. Houve diferença no espectro de gotas gerado pelo herbicida aplicado individualmente e em associações com fertilizante foliar e outro herbicida. A taxa de aplicação apresentou elevada variabilidade, com distribuição espacial de pertinências muito distantes dos valores ótimos.Palavras-chave: krigagem indicativa; pulverização; silvicultura de precisão; tecnologia de aplicação.

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The aim of this study was to evaluate spatial behavior and temporal stability of rainfall and mean air temperature in the state of Bahia, using historical series from 1975 to 2011 and 1961 to 2009, respectively. The analyses were performed considering the accumulated variables of each month of the historical series. The accumulated monthly totals were divided by the number of years of observation, obtaining the monthly average values of rainfall and air temperature for each measurement point. The data were submitted to descriptive statistical analysis and linear correlation studies. Geostatistical analysis was used to verify the existence and quantify spatial dependence between the values of the studied variables. In addition, the maps were submitted to algebra operations, calculating the spatial difference between months for each of the variables. For that purpose, the difference between one month and its subsequent period was calculated in order to establish the behavior of the variables over time. Climatic variables showed a close relationship between each other, demonstrating their spatial and temporal variation, which is mainly dependent on the seasons of the year. The rainfall and mean air temperature variables showed stable spatial behavior and high temporal stability between subsequent months.

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The objective of this study was to evaluate the spatial-temporal variability of leaf chlorophyll index and its relationship with cocoa yield. The experiment was carried out in an experimental area of cocoa production located in Ilhéus, Bahia State, Brazil. Leaf chlorophyll content was measured in September, October, January, February, March and April in the 2014/2015 season, at each sampling point of a regular grid by using a portable chlorophyll meter. Under the same conditions, yield was evaluated and the data were submitted to descriptive statistics and a linear correlation study. Geostatistical analysis was used to determine and quantify the spatial and temporal variability of leaf chlorophyll index and yield. Leaf chlorophyll index varied over the period evaluated, but the months of February, March and April showed no spatial dependence in the study area, indicating absence of temporal stability. Cocoa monthly yield, except in January, presented high spatial variability. Under the conditions of this study, it was not possible to establish a relationship between leaf chlorophyll index and cocoa yield.

The development of crops is related to their nutritional status and the leaf chlorophyll apparent index. The objective of this study was to use fuzzy classification to determine the degree of membership (fuzzy index -FI) of macronutrientes and leaf micronutrients classified as low, adequate and high, quantify the chlorophyll index and to determine the spatial variability of these attributes for the rubber tree (Hevea brasiliensis) (Fx 3864) at the initial stage of development, aiming at the definition of management zones. Sampling grid regulates at 6x7 m spacing was built to determine the attributes: chlorophyll a and b, macro and leaf micronutrients, totaling 100 sample points. The fuzzy classification and geostatistical was used to map the nutritional status of the rubber tree. In the fuzzy analysis the macronutrient map shows the degree of membership 0.50

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