Efeito da aplicação de resíduos de coco verde na cobertura do solo em pomar de coqueiro-anão irrigado

Abstract

The sustainable management of waste generated by coconut cultivation represents a significant environmental challenge, requiring the search for alternatives that offer a productive use for coconut processing residues. Given this scenario, this study is based on the hypothesis that the use of coconut fiber and husks as organic mulch contributes to moisture retention in sandy soils, characteristic of coconut-producing regions, which may result in better use of the by-product. In addition, coconut fiber has been shown to have an effect on soil physics and nutrient retention, reducing leaching. Therefore, the objective was to evaluate the effect on soil moisture and thermal stability using bark and bark and endocarp coverings on soil at depths of 10–50 cm under irrigated dwarf coconut cultivation in Paracuru, Ceará. The methodology consisted of analyzing three treatments using material left over from product manufacturing: No Cover (T1), Cover with Husk without endocarp (T2), and Cover with a mixture of Husk and Endocarp (T3). Laboratory tests were conducted to determine soil water retention curves and field monitoring was performed using moisture and temperature sensors at depths of 0-10 cm, 20-30 cm, and 30-50 cm. The results showed that the sensors were highly accurate in monitoring water dynamics, allowing us to observe that areas with organic cover (T2 and T3) maintained volumetric moisture contents up to 15% higher than bare soil, especially in the 0-20 cm layer. Analysis of the retention curve showed that the presence of residue positively alters water availability in the soil, increasing available water and slowing water loss through direct evaporation. In addition, the mulch acted as an efficient thermal insulator, reducing the soil temperature range by up to 5 °C during peak radiation times. It is concluded that the use of coconut waste as mulch is an efficient water and soil engineering practice, as it improves moisture conservation, reduces the temperature of the soil profile, and offers an ecological solution for the disposal of industrial by-products, optimizing water use efficiency in coconut production in semi-arid regions.