Soil quality indicators in a rhodic kandiudult under different uses in northern Parana, Brazil

Abstract

SUMMARYSustainable use of soil, maintaining or improving its quality, is one of the goals of diversification in farmlands. From this point of view, bioindicators associated with C, N and P cycling can be used in assessments of land-use effects on soil quality. The aim of this study was to investigate chemical, microbiological and biochemical properties of soil associated with C, N and P under different land uses in a farm property with diversified activity in northern Parana, Brazil. Seven areas under different land uses were assessed: fragment of native Atlantic Forest; growing of peach-palm (Bactrys gasipaes); sugarcane ratoon (Saccharum officinarum) recently harvested, under renewal; growing of coffee (Coffea arabica) intercropped with tree species; recent reforestation (1 year) with native tree species, previously under annual crops; annual crops under no-tillage, rye (Cecale cereale); secondary forest, regenerated after abandonment (for 20 years) of an avocado (Persea americana) orchard. The soil under coffee, recent reforestation and secondary forest showed higher concentrations of organic carbon, but microbial biomass and enzyme activities were higher in soils under native forest and secondary forest, which also showed the lowest metabolic coefficient, followed by the peach-palm area. The lowest content of water-dispersible clay was found in the soil under native forest, differing from soils under sugarcane and secondary forest. Soil cover and soil use affected total organic C contents and soil enzyme and microbial activities, such that more intensive agricultural uses had deeper impacts on the indicators assessed. Calculation of the mean soil quality index showed that the secondary forest was closest to the fragment of native forest, followed by the peach-palm area, coffee-growing area, annual crop area, the area of recent reforestation and the sugarcane ratoon area.Index terms: bioindicators, land use, metabolic coefficient, microbial biomass, soil enzymes, soil quality. RESUMO: INDICADORES DE QUALIDADE EM UM NITOSSOLO SOB DIFERENTES USOS NO NORTE DO PARANÁO uso sustentável do solo, mantendo ou aumentando sua qualidade, é um dos objetivos da diversificação na propriedade agrícola. Nesse aspecto, bioindicadores relacionados à ciclagem de C, N e P podem ser utilizados na avaliação do tipo de uso na qualidade do solo. O objetivo deste trabalho foi avaliar atributos químicos, microbiológicos e bioquímicos do solo, associados ao C, N e P, sob diferentes tipos de uso em uma propriedade agrícola com atividade diversificada no norte do Paraná. Foram avaliados sete tipos de uso do solo: fragmento nativo de Floresta Atlântica; cultivo de pupunha (Bactrys gasipaes); soqueira de cana-de-açúcar (Saccharum officinarum) recém colhida, em reforma; cultivo de café (Coffea arabica) intercalado com espécies arbóreas; reflorestamento recente (1 ano) com espécies arbóreas nativas, em área anteriormente ocupada com culturas anuais; cultivos anuais em sistema de plantio direto na palha, centeio (Cecale cereale); e mata secun...

Indicadores Microbiológicos de Solo em Pastagem com Aplicação Sucessiva de Dejetos De Suínos

“…O uso de diferentes doses de dejetos líquidos de suínos e o preparo do solo também influenciaram a atividade enzimática do solo, que apresentou diferentes tendências de acordo com a enzima (celulase, arilsufatase e fosfatase ácida), as diferentes doses de dejetos utilizadas e o manejo e a profundidade do solo estudada, de modo que a atividade das enzimas do solo foi considerada uma medida sensível capaz de detectar mudanças no solo em razão da aplicação de dejetos de suínos (Balota et al, 2011). A urease também demonstrou ser uma das enzimas mais sensíveis na análise de indicadores de qualidade do solo no Paraná, promovendo os mais distintos níveis entre diferentes usos do solo (Kuwano et al, 2014).…”

Emission of CO2 and soil microbial activity in sugarcane management systems

“…Kuwano et al (2014), working with soils under different uses in Northern Paraná, observed that the sugarcane areas under the burning system presented the highest qCO 2 , probably as a result of the burning before harvest, which decreases soil carbon inputs; moreover, the disturbance of the soil through heavy tillage on the renovation of the sugarcane plantation disrupts the microbial community not only by the breakdown of soil aggregates, but also by the loss of water from the soil.…”

“…Thus, an ecosystem out of balance will present high values of qCO 2 and low values of qMIC, which indicates greater energy consumption and higher level of stress of the biomass (Anderson and Domsch, 1990;Evangelista et al, 2013;Kuwano et al, 2014).…”

Indicators of soil quality in the implantation of no-till system with winter crops

“…In addition, the activities of dehydrogenase and cellulase were associated to fodder radish cropping, and in a lesser extent, to the multicropping of cover crops, as observed in the PCA analysis (Figure 2). The treatment with wheat also decreased the L-C in 2009, as a possible result of a stimulus to the microbial activity mediated by root exudation during vegetative growth, followed by deposition of residues more resistant to degradation on the soil after harvest, with larger C/N ratio, which makes more difficult the humification and formation of L-C. Lower concentrations of L-C in the soil cropped with fodder radish and wheat are in agreement with lower soil respiration, because microbial communities use more easily the more labile C fractions as substrate for growth and maintenance (BINI et al, 2013;BLAIR et al, 1995;KUWANO et al, 2014).…”

“…The soil microbial biomass works as transitory reservoir of nutrients originated from mineralization of SOM or fertilizers (CARDOSO et al, 2013), reducing losses like phosphate fixation and nitrate leaching (FAGOTTI et al, 2012;FRANK;GROFFMAN, 2009;RANGEL;. Considering that the speed of decomposition of plant residues rely on its chemical composition, mainly the C to N ratio and lignin content, the type of residue also affect the microbial activity and biomass (BINI et al, 2013;KUWANO et al, 2014).…”