Chemical and biological properties of phosphorus-fertilized soil under legume and grass cover (Cerrado region, Brazil)

Abstract

SUMMARYThe use of cover crops has been suggested as an effective method to maintain and/or increase the organic matter content, while maintaining and/or enhancing the soil physical, chemical and biological properties. The fertility of Cerrado soils is low and, consequently, phosphorus levels as well. Phosphorus is required at every metabolic stage of the plant, as it plays a role in the processes of protein and energy synthesis and influences the photosynthetic process. This study evaluated the influence of cover crops and phosphorus rates on soil chemical and biological properties after two consecutive years of common bean. The study analyzed an Oxisol in Selvíria (Mato Grosso do Sul, Brazil), in a randomized block, split plot design, in a total of 24 treatments with three replications. The plot treatments consisted of cover crops (millet, pigeon pea, crotalaria, velvet bean, millet + pigeon pea, millet + crotalaria, and millet + velvet bean) and one plot was left fallow. The subplots were represented by phosphorus rates applied as monoammonium phosphate (0, 60 and 90 kg ha -1 P 2 O 5 ). In August 2011, the soil chemical properties were evaluated (pH, organic matter, phosphorus, potential acidity, cation exchange capacity, and base saturation) as well as biological variables (carbon of released CO 2 , microbial carbon, metabolic quotient and microbial quotient). After two years of cover crops in rotation with common bean, the cover crop biomass had not altered the soil chemical properties and barely influenced the microbial activity. The biomass production of millet and crotalaria (monoculture or intercropped) was highest. The biological variables were sensitive and responded to increasing phosphorus rates with increases in microbial carbon and reduction of the metabolic quotient.Index terms: microbial biomass carbon, microbial activity, organic matter, cover plants, Cerrado.( RESUMO: ATRIBUTOS QUÍMICOS E BIOLÓGICOS DO SOLO COM COBERTURA DE LEGUMINOSAS, GRAMÍNEA E DOSES DE FÓSFORO, EM REGIÃO DE CERRADO, BRASILA utilização de plantas de cobertura é sugerida como método fundamental para manter e, ou, elevar o teor de matéria orgânica no solo, mantendo e, ou, melhorando as condições físicas, químicas e biológicas dele. Os solos do Cerrado apresentam baixa fertilidade, consequentemente baixos teores de fósforo (P), que se relacionam a todas as etapas metabólicas da planta, por essas fazerem parte dos processos de síntese proteica e energética, além de interferir no processo fotossintético. Este trabalho objetivou avaliar a influência de plantas de coberturas e doses de P sobre os atributos químicos e biológicos do solo. O trabalho foi conduzido em Selvíria, MS, em Latossolo Vermelho distrófico, com delineamento de blocos casualizados em esquema de parcelas subdivididas, com plantas de cobertura (milheto, guandu, crotalária, mucuna-preta, milheto + guandu, milheto + crotalária e milheto + mucuna-preta) e pousio nas parcelas e doses de P (0, 60 e 90 kg ha -1 de P 2 O 5 , na forma de monoamônio fosfato), nas subparce...

Biological Attributes of the Soil with Intercaled Crops and Oil Palm (Elaeis guineensis Jacq.): Sustainable Management in the Amazon

“…Positive and significant correlation between OM, C-BMS and, the enzyme acid phosphatase, (r) of 0.71 and 0.90 (p≤0.01) respectively. Data that corroborate with those obtained by [83][84][85][86][87][88][89][90][91][92], when they found significant correlations between OM and acid phosphatase activity. These types of correlations are important from the point of stability of the soil fertility of the different systems.…”

“…Highly significant but negative correlation was observed between qCO 2 and OM, (r) of -0.76 (p≤0.01), and a highly significant and negative correlation between qCO 2 and RBS and C-BMS with (r) -0.55 and -0.94 (p≤0.01) ( Table 3), data corroborated by [85][86][87]. Positive and significant correlation between the OM, C-BMS with the enzyme β-glucosidase, (r) of 0.70 and 0.74 (p≤0.01).…”

“…g -1 C-BMS) ( Table 1). According of [61][62], low values of qCO 2 indicate a more stable environment with better quality in the physical, chemical and biological attributes, which demonstrates a more balanced ecosystem in the pasture areas, however, in the cultures intercalated with the replacement of the cover occurs more rapid decomposition of the vegetal residues, increasing the metabolic quotient [63].…”

Cover crops in coffee management in production

“…Plants intercropped with coffee can contribute to the physical, chemical, and biological characteristics of the soil (Souza et al, 2013) increasing its biodiversity with a positive effect on reducing phytonematoids. Kubo et al (2013), explain that certain Brachiaria species such as Tagetes patula, contribute to the reduction of populations of some phytonematoid species such as R. similis, Pratylenchus spp., M. incognita, and H. multicinctus.…”

Dinâmica do fósforo no solo em função da adição de ácidos orgânicos de baixa massa molar

“…As principais áreas agrícolas no Brasil estão localizadas no bioma Cerrado. Mais de 50% dos solos do cerrado são Latossolos (LOPES, 1994), que tem alta habilidade de fixar fosfato, fazendo a maioria do P aplicado com fertilizantes fique pouco disponível para o crescimento das culturas (CARVALHO et al, 2014;MOREIRA et al, 2014;SOUZA et al, 2013). Embora a produtividade agrícola nos Latossolos no Brasil tenha aumentado intensivamente pelas adições de calcário, P e outros nutrientes (ASSOCIAÇÃO NACIONAL PARA A DIFUSÃO DE ADUBOS -ANDA, 2015; COMPANHIA NACIONAL DE ABASTECIMENTO -CONAB , 2013), maneiras mais rentáveis de manejar o P são desejáveis.…”