Growth and nutrient accumulation of Brazil nut trees(Bertholletia excelsa) in agroforestry at different fertilizer levels

作     者：Gotz Schroth Maria do Socorro Souza da Mota Maria Elizabeth de Assis Elias 

作者机构：C.P. 513 Santarem PA 68109-971 Brazil Centro de Estudos Avanqados de Promoqao Social e AmbientalAv. Mendonqa Furtado 3979 Santarem PA 68040-050 Brazil Universidade Federal do Amazonas Manaus AM 69077-000Brazil 

出 版 物：《Journal of Forestry Research》 (林业研究（英文版）)

年 卷 期：2015年第26卷第2期

页      面：347-353页

核心收录：

学科分类：081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 09[农学] 0903[农学-农业资源与环境] 

基　　金：funded by the German Ministry of Education and Research(BMBF) the Brazilian Conselho National de Desenvolvimento Científico e Tecnológico(CNPq) 

主　　题：Allometric equation Amazon Nutrient competition Nutrient recycling Plant mineral nutrition Soil fertility Silviculture 

摘      要：The Brazil nut tree（Bertholletia excelsa） is a frequent component of agroforestry systems in the Amazon because of its adaptation to nutrient-poor upland soils and multiple *** investigated the aboveground biomass production（kg dry weight）,nutrient uptake and requirements（N,P,Ca,Mg,K） of Brazil nut trees of different sizes grown under agroforestry conditions and fertilized at different *** of 70 experimental trees with different size were harvested and stem,branches and leaves were *** contents were determined for three trees of varying *** tree growth was fast,but variability was high,suggesting considerable potential for the improvement of this economically important *** trees responded to increased levels of fertilizer and lime with significantly increased foliar nutrient contents and growth,probably because of the improved availability of Mg and Ca for which the species seems to have a relatively high *** contrast to Brazil nut trees grown in forest or dense plantations,the agroforestry trees invested a substantial part of their biomass and nutrients in large branches and developed spreading *** improve stem form,reduce competition with associated crops for light and recycle nutrients,regular pruning of lower branches or planting arrangements that favor self-pruning are *** measures would also increase the recycling of Ca and Mg,large quantities of which are contained in the branches.