Banca de DEFESA: MARCO AURÉLIO BARBOSA ALVES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARCO AURÉLIO BARBOSA ALVES
DATE: 13/06/2023
TIME: 14:00
LOCAL: Video conferência
TITLE:

Water erosion, soil water infiltration and carbon stock in Cerrado-Amazon transition areas, with different uses and coverage

KEY WORDS:

Soil losses, surface runoff, soil water infiltration models, Teles Pires river basin

PAGES: 105
BIG AREA: Ciências Agrárias
AREA: Engenharia Agrícola
SUBÁREA: Engenharia de Água e Solo
SPECIALTY: Conservação de Solo e Água
SUMMARY:

Agricultural frontier regions, such as the north of the State of Mato Grosso-Brazil, have been undergoing significant transformations arising from the conversion of native forests into areas for crops and pasture. Furthermore, the management systems adopted may favor the occurrence of water erosion, influenced by changes in infiltration capacity and soil carbon content. The objective of this study was to quantify soil and water losses, infiltration rate and soil carbon content in the sub-basins of the Caiabi and Renato rivers, located in the watershed of the Teles Pires river, in the northern region of the State of Mato Grosso, Brazil. . A physical characterization of the soil was carried out with the determination of granulometric analysis, microporosity and macroporosity, particle and soil density and hydraulic conductivity. Using the InfiAsper rainfall simulator, soil and water losses, and soil water infiltration characteristics were determined considering a 3 x 3 experimental arrangement, with 3 regions of the two sub-basins (source, middle and mouth) and 3 soil coverage/management conditions (covered soil, uncovered soil, uncovered soil + tillage), with 4 repetitions. Soil and water losses were also quantified in the straw condition in the Caiabi River sub-basin. Based on data measured in the field, water infiltration into the soil was evaluated using the Kostiakov-Lewis, Horton and Philip models. The levels and stock of carbon were quantified in the areas of crop, pasture and native forest in the same regions of the aforementioned sub-basins. The predominant granulometric class in the hydrographic sub-basins is sand, especially in the mouths, with total sand above 80%. Soil losses increased as the soil cover was removed and the plot subjected to scarification, which in turn provided increased infiltration capacity compared to uncovered soils. In the Caiabi river sub-basin, soil carbon contents and stock correlated positively with the silt fraction and negatively with sand in the Caiabi river basin, while in the Renato river sub-basin there was a positive correlation with clay. The pasture areas showed better conditions for water infiltration into the soils when they were scarified, with Horton and Philip's models being the ones that best fit the field data. Soil carbon contents correlated negatively with sand in the Caiabi river basin and positively with clay in the Renato river. The native forest is not the soil occupation that most stored carbon.

COMMITTEE MEMBERS:
Presidente - 1224578 - DANIEL FONSECA DE CARVALHO
Interno - 1060711 - MARCOS GERVASIO PEREIRA
Externo ao Programa - 2131822 - CONAN AYADE SALVADOR - UFRRJExterno à Instituição - CORNÉLIO ALBERTO ZOLIN - EMBRAPA
Externo à Instituição - PAULO TARSO SANCHES DE OLIVEIRA - UFMS