Alteração de indicadores de qualidade de solos afetados por sais no perímetro irrigado de São Gonçalo-PB.

Abstract

Antropic actions and inadequate agricultural practices can cause soil degradation, and among these, inadequate irrigation management is prominent in semi-arid regions. The objective was to evaluate the alteration of soil quality indicators affected by salts in the Irrigated Perimeter of São Gonçalo-PB. The experimental design was completely randomized, using three replicates. Soil samples were collected from three salt - affected areas, with an area slightly affected by salts (A1) and other moderately affected (A2), previously cultivated with coconut, and a Caatinga area with predominance of jurema Mimosa tenuiflora (Wild) Poir, and little affected by salts (AR), as reference. The biological attributes analyzed, consisting of actinomycetes, bacteria and fungi density, were evaluated by means of the serial dilution of the samples in culture media specific to each microorganisms group, using amide casein, nutrient agar and potato dextrose agar for each group, respectively. In all samples of the studied areas the presence of bacteria, fungi and actinomycetes were detected. The fungi density was higher in the three studied areas. The densities of fungi and actinomycetes were not altered by soil salinity. The bacteria density was negatively altered with increasing salinity.