Efeitos do manejo sustentável da Caatinga sob os atributos físicos do solo

Objetivou-se avaliar a qualidade do solo, em áreas da Caatinga submetidas a diferentes sistemas de manejo, tendo como parâmetros os atributos físicos do solo. As formas de manejo adotadas foram: (1) área de manejo sustentável da Caatinga; (2) área de Caatinga com manejo convencional; e (3) área de Caatinga considerada mata nativa. Decorridos 5 anos, foram coletadas amostras de solo nas áreas nas profundidades 0,00-0,20 m e 0,20-0,40 m para análise dos atributos físicos do solo. Os resultados evidenciaram maior compactação do solo na área de manejo convencional. O manejo sustentável da Caatinga mostrou-se uma técnica promissora para manutenção e recuperação das propriedades físicas do solo

Flow rate variation and biological agents that obstruct drippers of swine effluent

Emitter clogging is the major problem of drip irrigation systems operating with wastewater. The objective of this study was to evaluate the alteration of the flow rate variation coefficient (FVC) and to identify the biological agents that cause obstruction in drip units operating with swine effluent and public water supply. The experiment was set up in a split-plot scheme, with the times of application of swine effluent and public water supply in the main plots and dripper types in the secondary parcels, evaluating times of FVC in the tertiary parcels, using a completely randomized design (CRD) with three repetitions. The FVC of the drip subunits was calculated on every 40 hours as well as the microscopic analysis of the biological agents of clogging, until 160 h. At the end of the tests, biofilm samples were collected in each drip unit to identify the groups of predominant bacteria. The results indicated that the FVC was effective in detecting the clogging of the emitters, evidencing that the construction characteristics and the times of application of swine effluent and of the public water supply interfere in this process. Microscopic analyzes of the biofilm indicated that the main biological agents that caused obstruction were algae, bacteria, fungi and protozoa

Flow rate variation and biological agents that obstruct drippers of swine effluent

Emitter clogging is the major problem of drip irrigation systems operating with wastewater. The objective of this study was to evaluate the alteration of the flow rate variation coefficient (FVC) and to identify the biological agents that cause obstruction in drip units operating with swine effluent and public water supply. The experiment was set up in a split-plot scheme, with the times of application of swine effluent and public water supply in the main plots and dripper types in the secondary parcels, evaluating times of FVC in the tertiary parcels, using a completely randomized design (CRD) with three repetitions. The FVC of the drip subunits was calculated on every 40 hours as well as the microscopic analysis of the biological agents of clogging, until 160 h. At the end of the tests, biofilm samples were collected in each drip unit to identify the groups of predominant bacteria. The results indicated that the FVC was effective in detecting the clogging of the emitters, evidencing that the construction characteristics and the times of application of swine effluent and of the public water supply interfere in this process. Microscopic analyzes of the biofilm indicated that the main biological agents that caused obstruction were algae, bacteria, fungi and protozoa

Performance of drip emitters for different pressures and application of cashew nuts wastewater

Este estudio tuvo como objetivo analizar el efecto de diferentes presiones de operación en la obstrucción de goteros y en el coeficiente de uniformidad de Christiansen (CUC) en los sistemas de riego por goteo que operan con la agua residual de castanha de cajú. El experimento se estableció en el esquema de parcelas subsubdivididas, con presiones de operación en parcelas (70, 140, 210 y 280 kPa), tipo de goteros en parcelas subdivididas (G1, G2 y G3) y los tiempo de operación em parcelas subsubdivididas (0, 20, 40, 60, 80, 100, 120, 140 y 160 h), en el diseño completamente al azar con tres repeticiones. El CUC de unidades de riego se midió cada 20 h hasta que el tiempo de funcionamiento de 160 h. Los resultados mostraron que los goteros G2 y G3 son los más adecuados para la aplicación de la agua residual de castanha de cajú, y la presión de funcionamiento de 140 kPa minimiza la obstrucción en los goteros G1, G2 y G3 cuando se opera con la agua residual de castanha de cajú.The effect of different operating pressures is investigated with regard to the clogging of drip emitters and Christiansen uniformity coefficient (CUC) in drip irrigation systems operating with wastewater from cashew nut processing. The experiment was set on a split-split-plot scheme, with operating pressures (70, 140, 210 and 280 kPa) on plots, emitter models (G1, G2 and G3) on split-plots and assessment times (0, 20, 40, 60, 80, 100, 120, 140 and 160 h) on split-split-plots, in a completely randomized design, with three replicates. CUC of irrigation units was measured every 20 h up to operation time of 160 h. Results showed that drip emitters G2 and G3 were the most suitable for the application of cashew nutwastewater, and the operating pressure of 140 kPa minimized clogging in drip emitters G1, G2 and G3 when operated with cashew nut wastewater

Performance of drip emitters for different pressures and application of cashew nuts wastewater

The effect of different operating pressures is investigated with regard to the clogging of drip emitters and Christiansen uniformity coefficient (CUC) in drip irrigation systems operating with wastewater from cashew nut processing. The experiment was set on a split-split-plot scheme, with operating pressures (70, 140, 210 and 280 kPa) on plots, emitter models (G1, G2 and G3) on split-plots and assessment times (0, 20, 40, 60, 80, 100, 120, 140 and 160 h) on split-split-plots, in a completely randomized design, with three replicates. CUC of irrigation units was measured every 20 h up to operation time of 160 h. Results showed that drip emitters G2 and G3 were the most suitable for the application of cashew nut wastewater, and the operating pressure of 140 kPa minimized clogging in drip emitters G1, G2 and G3 when operated with cashew nut wastewater