Recuperação de área degradada com o cultivo da palma forrageira (Opuntia stricta Haw) adubada com biossólido

Abstract

The soil degradation scenario is worrisome in Brazil and in the world, due to the improper use of soil, such as: deforestation, monoculture, pasture, use of pesticides and absorption of nutrients by fallow or without mineral replacement , end up generating several types of degradation, causing in infertile soils, being necessary its recovery. In this context, this work was developed with the objective of evaluating the effects of fertilization with biosolids (sewage sludge) in a degraded area cultivated with forage palm. The Mexican Elephant Ear (Opuntia stricta Haw), in the São Miguel Arcanjo Site, in the municipality of Parazinho, RN. In order to do so, an experimental area was implanted in this municipality, with the cultivation of the irrigated forage palm, densified and organically fertilized. A randomized complete block design was used, with 04 treatments (T1 - control, T2 - T3 - fertilized with a dose of biosolid and T4 - fertilized with two doses of biosolid) and 06 repetitions in each block. From the chemical and physical characterization of the soil, it was observed that without the cultivation of the palm in the degraded area there would be no conditions of self recovery, since the degraded area presented a low resilience rate, making natural regeneration impossible. Palm cultivation recovered physical attributes of the soil in the recovering area, as a result of the greater protection provided to the soil in front of the erosive process diagnosed in the locality and restored the degraded soil fertility, raising the pH, CTC and saturation value of bases, especially in relation to exchangeable calcium and magnesium contents. The results indicate that the cultivation of the irrigated palm responded favorably to the organic fertilization, reflecting directly on the production of green mass, height and plant width. Finally, it is concluded that the degraded area presented conditions to recover, due to the adopted recovery alternative, being economically feasible, besides being environmentally safe the palm cultivation with biosolids, under conditions similar to those presented in this study.