Banca de DEFESA: HEMELYN SOARES DAS CHAGAS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : HEMELYN SOARES DAS CHAGAS
DATE: 30/09/2020
TIME: 14:00
LOCAL: Online
TITLE:

MINERAL AND ORGANIC FERTILIZATION ON GROWTH, NODULATION EFFICIENCY AND NITROGEN COMPOUNDS IN EXOTIC AND NATIVE CROTALARIA FROM CARAJAS

KEY WORDS:

Carajás Mineral Complex, mining, revegetation, crotalaria

PAGES: 47
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Fertilidade do Solo e Adubação
SUMMARY:

Mining in the Carajás Mineral Province (PMC) started in the 1980s, with excavation being carried out by means of an open pit, forming mine pits and waste piles, which are revegetated to reduce negative environmental impacts. Brazilian environmental legislation, in the case of a federal conservation unit, such as the Carajás National Forest (FLONACA) - where the Carajás Mineral Complex has been installed for the extraction of iron, copper and manganese - recommends the use of exotic species cocktails / non-aggressive and easy to control commercials, and FLONACA's native forest and canga species for the revegetation of areas impacted by mining. However, the selection of native species requires the best knowledge of their growth and nutritional requirement. The objective of the present study was to evaluate mineral and organic fertilization on growth, efficiency of nitrogen use, nodulation, and the production of nitrogen compounds from two species of the genus Crotalaria, the first being Crotalaria spectabilis (commercial / exotic species from FLONACA ) used to revegetate areas impacted by mining in Carajás, and the second to Crotalaria maypurensis (native to the Carajás ferruginous canga). The latter is not yet used in revegetation activities at PMC, however, it has potential for use in revegetation due to the high production of seeds and rapid production of biomass. The experiment was conducted in a greenhouse, with two aforementioned species, which were grown under different fertilization conditions (Control - no fertilizer added; NPK; NPK + Micronutrients; NPK + micronutrients + Organic compound; PK; PK + Micronutrients; PK + Micronutrients + organic compound) constituting 7 treatments, with 5 repetitions. Carajás iron mining waste was used as a substrate for the growth of both species. After 90 days of cultivation in the treatments, biometric data, nutritional efficiency, nodulation efficiency, and quantitative analysis of amino acids and nitrogen compounds (nitrate and ammonia) were evaluated. The results obtained revealed that, regardless of the treatments applied, the commercial species showed higher plant height than the native species. In the same way, the commercial species was more responsive to the treatments used to promote greater production of roots and shoots. Specifically, the treatment NPK + Micronutrients, promoted the highest production of biomass in the commercial species, while the treatment NPK + micronutrients + Organic compost promoted greater growth in the native species. The native species showed a higher number of nodules and dry nodule mass. However, this did not reflect greater efficiency in nodulation or in the efficiency in the use of nitrogen, since the commercial species was superior in these variables. In addition, the species studied showed different responses to nitrogen compounds in their tissues. While C. maypurensis tended to have a higher concentration of nitrate in leaves and nodules, the species C. spectabilis ammonium is the predominant form of nitrogen. The results show that the species present differentiated nitrogen metabolism. Although the native species shows less growth, its use in the revegetation of mined areas in FLONACA must be taken into account by native species.

BANKING MEMBERS:
Presidente - 030.493.086-56 - SILVIO JUNIO RAMOS - ITV
Interno - 1803899 - ALLAN KLYNGER DA SILVA LOBATO
Externo à Instituição - AUGUSTO JOSÉ SILVA PEDROSO - IFPA
Externo à Instituição - CECÍLIO FROIS CALDEIRA JÚNIOR - ITV