Evaluation of compost application on soil organic carbon sequestration and physic-chemical properties in olive grove agroecosystems of NE Portugal
Artigo de Conferência
Global carbon (C) cycle and atmosphere pollution remediation depended directly on C terrestrial
sequestration and storage. In this context, soil organic carbon (SOC) plays an extremely important
role by creating and enlarging C pools, such as organic amendments input over croplands. The
present research aims to evaluate the outcomes from three types of compost (A, B and C) to a
Leptosol, in an olive grove (NE Portugal) and its relationship with soil physic-chemical properties.
The compost production is derived from an agroindustry by-product, namely olive pomace mixed
with sheep manure and almond shell in different proportions. Preview studies showed no
significant difference for SOC concentration on top layer soil (0-5 cm) for different dosage (10 and
40 ton ha-1) after 1 year application. The olive grove conservative management also presented no
significant difference of SOC concentration among spatial distribution (elevation, x and y
coordinates), which means there is practically no soil loss in 15% slope. Furthermore, the soil ΔpH
(from KCl to H2O) presented variable charge of 1.21 in the control group, for that reason, the ΔpH
was used as an indicator due the organic matter input. Besides, results presented a ΔpH of 0.98,
1.15 and 0.71, respectively for treatments A, B and C (10 ton ha-1) on 0-5 cm layer soil, with
significant difference between treatments, which demonstrated to be originated exclusively from
the organic matter, varying on the C quality of each one of the composts and not from the mineral
fraction of the soil. For 40 ton ha-1 dosage, the treatments A and B presented significant difference
compared to C (ΔpH 1.15, 1.18 and 0.56, respectively). In general terms, there is directly causeeffect over compost application and analytical analyzes, independently of dosage application and
type of compost.
