Economia circular no manejo de resíduos da cafeicultura e efeitos sobre o sistema solo-planta

Abstract

Brazil stands out in the production of coffee. This chain generates a high amount of waste that can cause environmental problems. The circular economy is an alternative that allows for the appropriate management of this waste by reusing and recycling by-products that would otherwise be discarded. The use of these residues as soil conditioners in coffee farming can improve important fertility components and promote biological activity, which are fundamental to achieving sustainable production. The objective of the study was to compare different forms of waste valuation regarding the soil conditioning effect on coffee cultivation, on two coffee producing properties (NKG: large-scale corporate agriculture and PX: family agriculture) in the town of Santo Antônio do Amparo-MG. The treatments evaluated were: 1) coffee husk, 2) organic compost, 3) Bokashi, 4) biochar, 5) COMBI (compost + biochar), 6) commercial organomineral and 7) conventional fertilizer (control). All treatments received the same dose of mineral fertilizer, except treatment 6. The experiment was conducted in a randomized block design, with four replications. Analyzes of conditioners, soil fertility, soil bioindicators and productivity were carried out. In NKG, under conventional fertilization, the lowest pH value was observed (4.8). COMBI significantly increased (p<0.05) the values of TB, t, T and V in relation to the control. On the other hand, on the PX property, the organic compound and the control treatment presented the lowest pH values. Organic compost and biochar were the ones that most increased the CTC at pH 7.0 (T) with an increase of 17 and 12% in relation to the control. Most indicators had greater activity in the PX area due to the higher organic matter content in the soil, which was more a function of the management history than the use of soil conditioners. The treatments did not influence productivity in NKG and, in PX, biochar had the highest productivity. Compost, biochar and COMBI soil conditioners showed the best conditioning effect and organic matter is a strong component for soil biological indicators and productivity. The study should be evaluated for a longer period of time for more consolidated results.