Banca de QUALIFICAÇÃO: CLAUNITA NOVAIS ALVES

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : CLAUNITA NOVAIS ALVES
DATE: 28/02/2023
TIME: 14:30
LOCAL: Videoconferência - meet.google.com/cpa-gsfe-mop
TITLE:

Dry mass production, nutrient cycling and phytomass decomposition rate of green manures intercropped with full sun system cacao 

KEY WORDS:

Theobroma cacao L, soil cover, phytomass, cover crops

PAGES: 20
BIG AREA: Outra
AREA: Ciências Ambientais
SUMMARY:

Cover crops are used to produce straw to promote soil protection, organic matter increment and nutrient cycling and release after decomposition. This is a technique used in orchards in general for soil conservation. The objective of this study was to evaluate dry matter production, nutrient cycling and the rate of decomposition of green manures intercropped with full sun cropping system cacao. The experiment was carried out at CEPLAC (Comissão Executiva do Plano da lavoura Cacaueira) in Ilhéus-BA, with a randomized block design with four treatments and four replications. Treatments consist of green manure: dwarf pigeon pea (Cajanus cajan (L). Millsp, brachiaria (Urochloa decumbens), spontaneous vegetation and uncovered soil). The dry mass produced and the nutritional composition of the green manure were evaluated and nutrient cycling was calculated. The dynamics of decomposition of plant residues was evaluated using the “litter bags” methodology. The average dry matter production between treatments was 10 Mg ha^-1 with no difference between evaluated treatments. For nutrient cycling, the values found for macronutrients, spontaneous vegetation and brachiaria showed the highest accumulation of the nutrient potassium (K). Spontaneous vegetation and brachiaria showed the highest rate of decomposition during the 136 days of leaf mass evaluation and the shortest half-life (T_1/2). Pigeonpea had the lowest decomposition speed, remaining longer in the soil and consequently had the longest half-life (T_1/2). Cover crops represent an advantageous practice for nutrient cycling and also for soil protection, especially when intercropped with legumes and grasses.

COMMITTEE MEMBERS:
Presidente - 1099329 - JOAO CARLOS MEDEIROS
Externo ao Programa - 1720621 - CARLOS EDUARDO PEREIRA - UFSBExterno à Instituição - HENRIQUE ANTUNES DE SOUZA
Externo à Instituição - PAULO HENRIQUE MARQUES MONROE