Banca de DEFESA: VICENTE SANTOS DE SOUSA
Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.STUDENT : VICENTE SANTOS DE SOUSA
DATE: 23/06/2023
TIME: 14:00
LOCAL: Por videoconferência na sala do google meet
TITLE:
ORGANIC RESIDUES FOR ENRICHMENT OF THE STERIL USED IN THE CONSTRUCTION OF TECHNOSOL IN BAUXITE MINE
KEY WORDS:
bauxite mine spoil; technosolo; pigeon pea; recovery of degraded area; organic residues.
PAGES: 62
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Fertilidade do Solo e Adubação
SUMMARY:
One of the biggest challenges in bauxite mining is to ensure the reestablishment of vegetation in the post-mining area. The challenge is intensified in cases where topsoil is not available for the construction of the mine soil, being necessary to search for technologies to improve the bauxite mine spoil and thus guarantee the conditions of the plant establishment and, consequently, obtain the coverage of the soil in the initial stages of recovery of the mined area. OBJECTIVE: The objective of this work was to find the most efficient dose and source of organic matter (O.M.) to be incorporated into the substrate to promote the improvement of the spoil's physical and chemical attributes and ensure the development of the indicator plant. MATERIALS and METHODS: Two sources of M.O. namely: wood residues from suppression (WS) and dehydrated food residues (FR) from the company's activities, in three dosages 10, 20 and 40 t/ha-1 and a control (TT), which comprised seven treatments with 5 repetitions, arranged in CBD. Pigeon pea (Cajanus cajan) was used as an indicator plant. The evaluated parameters were the physical attributes: Density (Ds) and Total Porosity (Pt) and; The chemical attributes in layers 0-5, 5-10, 10-20, 20-40 cm. The variables related to the indicator plant were: plant dry biomass and height at 7 and 15 months of the experiment. Data were submitted to ANOVA and means compared by Tukey at 5% in the R-studio program. RESULTS: In both sampling periods, doses of 20 and 40t/ha-1 FR and 40 t/ha-1 WS provided a significant increase in plant height and dry biomass in relation to TT. From the chemical variables, statistical differences were detected for the organic C (orgC) and for the potential CTC in the 0-5cm layer (p-value < 0.05). For orgC, the treatments 40 t/ha-1 WS and 40 t/ha-1 FR were the maximizing doses, thus different from TT. Regarding soil CEC, only the dosage of 40 t/ha-1 WS was statistically different from TT only in the superficial layer at 7 months. For the other chemical attributes and at the other analyzed depths, there were no statistical differences in TT. Until the end of the experimental period, Ds and Pt did not respond to doses and sources of M.O. used. CONCLUSIONS: Treatments with organic matter sources at doses of 20 and 40 t/ha-1 FR and 40 t/ha-1 WS provided gains in plant height and dry biomass, presenting the best performance until the end of the experimental cycle ; The incorporation of 40 t/ha-1 WS and 40 t/ha-1 FR to the spoil had a positive effect on orgC in both sampling periods and 40 t/ha-1 WS positively affected CTC only at 7 months; Therefore, doses of 20 and 40 t/ha-1 FR and 40 t/ha-1 WS mixed with the bauxite mine spoil are the most promising for increasing the carbon content in the soil and producing plant dry biomass.
BANKING MEMBERS:
Presidente - 1552048 - NORBERTO CORNEJO NORONHA
Interno - 030.493.086-56 - SILVIO JUNIO RAMOS - ITV
Externo à Instituição - SÉRGIO MIANA DE FARIA - EMBRAPA
Externa ao Programa - 1741065 - VANIA SILVA DE MELO