Restoration of degraded pasture of Urochloa decumbens through different managements using mineral fertilizers and biochar ¹

Recuperação de pastagem degradada sob Urochloa decumbens por diferentes manejos utilizando fertilizantes minerais e biochar

ABSTRACT

Residues generated in sugarcane production such as biochar, originated from bagasse burning, are used as a fertilizer source, which can increase forage dry matter yield, as well as improving soil chemical attributes. The objective of this study was to evaluate the effects of using biochar from sugarcane bagasse burning and mineral fertilization, as well as their association, on the dry matter yield of Urochloa decumbens and on the chemical attributes of the soil. The design was randomized blocks, which consisted of eight treatments and four blocks. The treatments were: T1- mineral fertilization; T2- fertilization with limestone plus mineral fertilizer; T3- liming; T4- biochar; T5- biochar plus mineral fertilizer; T6- liming plus biochar; T7- double fertilization with biochar and T8- control. Association of mineral fertilizer and biochar was able to increase dry matter yield by up to 131% when compared to the control treatment during the first year. The use of fertilization strategies in the restoration of degraded area under U. decumbens does not interfere with soil chemical attributes, except for sulfur.

Key words:
organic residue; soil fertility; dry matter

HIGHLIGHTS:

The use of biochar had no influence on dry matter yield, when compared to mineral fertilizer treatments during the second year of use.

The use of biochar associated with mineral fertilizer during the first year increases the dry matter yield of Urochloa decumbens.

The management strategies to restore degraded pasture are important to reduce dependence on mineral fertilizers.