Respostas ecofisiológicas e produtivas de plantas juvenis de macaúba em consórcio com braquiária

• Autor(a) principal: Souza, Elma dos Santos
• Data de Publicação: 2013
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1209
• topic: Acrocomia aculeata; Silvipastoril; Assimilação de CO2; Sazonalidade hídrica; Espaçamentos; Acrocomia aculeata; Silvopastoral; Assimilation of CO2; Water seasonality; Spacings; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA

Acrocomia aculeata, popularly known as macauba, stands out for its significant capacity to produce oil, usable in both biodiesel and other industrial sectors. In addition there is the possibility of integral use of the fruit´s by-products that adds value to this palm. The species is very rustic and presents great ecological plasticity, which enables it to be used in agroforestry systems, such as silvopastoral. However, to prove the compatibility of macauba palm with silvopastoral practices is necessary to investigate the species ecophysiological aspects and productivity under this association and on different spacing. Thus, the objectives of this work were to evaluate the effect of the silvopastoral system, with brachiaria grass as the pasture component and juvenile macauba, under different spacing, as the arboreal component on: soil moisture, leaf area index, photosynthetic active radiation, gas exchange variables, growth, biomass production and carbon assimilation and accumulation. The experiment was conducted at the Araponga Experimental Station / UFV, in the municipality of Araponga - MG. Macauba plantlets were planted in five spacing in consortium with brachiaria. Evaluations were performed at different periods of natural water availability, rainy and drought seasons. The results pointed out that the soil moisture was not affected by plant spacing in a macauba-brachiaria association. The passage of photosynthetic active radiation to the understory was also not affected and dry matter production of Brachiaria remained satisfactory in all space treatments. The leaf area index was not affected by different spacing. In relation to gas exchange parameters, the absolute mean values in both seasons, indicated that the CO2 assimilatory process is continuous and sufficient to ensure the development and growth of macauba plants, although in the dry season there was a significant decrease of net photosynthesis. Growth variables, biomass, carbon accumulation and CO2 assimilation were not adversely affected by the spacing of juvenile macauba plants in consortium with brachiaria, which demonstrates continuous carbon sequestration over the period of analysis. Thus, up to the end of the of the analyses, the consortium of juvenile macauba plants with brachiaria was a feasible practice, since no effects were observed that may restrict the growth and development of both plant components. The choice of spacing between palm plants, for the silvopastoral system, depends on the purpose of agricultural practice. Additionally, the utilization of macauba in agroforestry systems showed considerable potential for carbon sequestration, making its cultivation environmentally sustainable.