Banca de DEFESA: VANESSA MELO DE FREITAS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : VANESSA MELO DE FREITAS
DATE: 31/03/2025
TIME: 14:00
LOCAL: online
TITLE:

ROCK POWDER, BIOCHAR, AND MICROBIAL INOCULATION IN THE PRODUCTION OF AÇAÍ PALM SEEDLINGS IN LOW-FERTILITY SOIL

KEY WORDS:

soil remineralization; soil fertility; nutrient availability; Brazilian Amazon

PAGES: 45
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Fertilidade do Solo e Adubação
SUMMARY:

The application of metabasalt powder and açaí seed biochar can stimulate the circular economy and bioeconomy in the Amazon, enhancing the sustainability of activities in the region. Additionally, the association of these materials with microbial inoculants may improve soil quality for agricultural cultivation in the region, such as açaí palm, which requires studies to assess the potential of this combination. The objectives of this study were to: i) characterize the metabasalt powder produced in the Carajás Mineral Province; ii) understand the changes in soil chemical attributes with the application of rock powder, biochar, and microbial inoculant; and iii) evaluate the growth of açaí palm seedlings in soils subjected to the application of these inputs. To this end, metabasalt fragments were collected and characterized for abrasion pH and nutrient content. The biochar was produced from the pyrolysis of açaí seeds (400 ºC) collected in the metropolitan region of Belém, Pará. The inoculant solution was composed of bacteria from the genera Amycolatopsis sp., Oceanobacillus sp., and Bacillus sp. The experiment included eight treatments: 1) natural soil, identified as S; 2) soil + rock powder, identified as S+P; 3) soil + biochar, identified as S+B; 4) soil + inoculant, identified as S+I; 5) soil + biochar + inoculant, identified as S+B+I; 6) soil + rock powder + biochar, identified as S+P+B; 7) soil + rock powder + inoculant, identified as S+P+I; and 8) soil + rock powder + biochar + inoculant, identified as S+P+B+I. After the experiment, the plants were evaluated for growth, nutrient content in plant tissue, and gas exchange, while the substrates were assessed for fertility. The rock powder contained several nutrients in quantities above those required by Brazilian legislation, including basic cations (Ca, Mg, and K) and micronutrients such as Fe and Mn. The experimental results indicated significant changes in soil fertility with the application of treatments, particularly rock powder, which considerably increased pH, sum of bases, and base saturation. The plants showed trends of greater growth with the application of biochar and inoculant, both individually and in combination with rock powder. Changes in gas exchange were also observed, especially in treatments with rock powder application. Several treatments promoted higher nutrient content in plant tissue, indicating the potential of these materials as sources of essential elements. The results of this study may support the use of mining by-products and agro-industrial residues to improve soil fertility in the Amazon, promoting the region's circular economy.

COMMITTEE MEMBERS:
Presidente - ***.493.086-** - SILVIO JUNIO RAMOS - ITV
Externo à Instituição - GABRIEL CAIXETA MARTINS - ITV
Externo à Instituição - JEFFERSON SANTANA DA SILVA CARNEIRO - NetZero
Externo à Instituição - JOSÉ AUGUSTO BITENCOURT