Multivariate Tools for Evaluating the Use of Organic Fertilizers on Soil Microbial Properties and Maize Yield

Layana Dorado Correia Belinato,Elston Elston Kraft,Patrícia Aparecida De Oliveira,Evandro Spagnollo,Rafael Solivo,Carolina Riviera Duarte Maluche Baretta,Dilmar Baretta

doi:10.5296/jas.v8i3.16073

Abstract

The global demand for protein led to the increase of animal production in the world and, mainly, in Brazil. As a consequence, there was an increase in the amount of waste produced, and the need to seek alternatives for its sustainable use. Microbial indicators and multivariate tools can assist in the proper measurement of the impact of the use of this waste on the soil. This study aimed to: 1) measure the effect of the application of organic fertilizers of animal origin in the no-tillage system on soil microbial attributes and its relationship with maize yield; 2) evaluate the potential of separation/discrimination of the different sources of organic fertilizers based on yield and soil microbial and chemical-physical attributes, using multivariate tools. Treatments consisted of annual application of: poultry manure (PM), liquid swine manure (LSM), poultry manure compost (PMC), swine manure compost (SMC), cattle manure compost (CMC) and control (C), without fertilization. Organic fertilizers promoted higher values of microbial biomass (MB) and MBC:TOC ratio in treatments CMC, SMC and PM in the first sampling season (E1), followed by PM, LSM and PMC in the second sampling period (E2). The data show that PM promoted microbial growth in both seasons, with higher metabolic efficiency increasing maize yield by 30% in relation to the treatment with the second highest production, PMC. Multivariate analysis techniques prove to be important tools to study soil quality indicators in systems which use organic fertilizers.

Highlights

The large number of animals in a small territorial area is a marked characteristic of the Brazilian animal production system, especially in southern Brazil, which leads to a large production of waste, often without adequate disposal
The mean values found varied in the treatments and evaluation periods from 122.03 to 311.90 mg kg-1 for microbial biomass carbon (MBC) (F = 25.75; P < 0.001), from 0.60 to 1.64% for the ratio between microbial biomass carbon and total organic carbon (MBC:TOC) (F = 23.85; P < 0.001), from 0.29 to 0.47 mg g-1 of soil per day for basal soil respiration (CO2-C)
For the first evaluation period (E1), microbial biomass increased in the areas that received fertilizers cattle manure compost (CMC), swine manure compost (SMC) and poultry manure (PM), which did not differ from one another, and the lowest values were found with liquid swine manure (LSM), control (C) and poultry manure compost (PMC) (Table 4)

Summary

Introduction

The large number of animals in a small territorial area is a marked characteristic of the Brazilian animal production system, especially in southern Brazil, which leads to a large production of waste, often without adequate disposal. Animals such as pigs and cattle can produce about 5 to 10% of their live weight in waste per day, whereas birds use only 40% of the food ingested (Konzen & Alvarenga, 2005). The behavior of the microbial population depends on the quality, type and quantity of the animal waste applied to the soil, as well as on the frequency of its application

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Conclusion