Dr Monica Santana², Dr Vanderlise Giongo¹

¹Embrapa Semiarido, Petrolina, Brazil, ²Universidade Federal do Ceara, Fortaleza, Brazil

Livestock farming drive the economy of semiarid regions, with the raising of cattle, goats and sheep, which survive for the most part of the resources offered by native vegetation. In the Brazilian semiarid region, approximately 70% of the woody species of the native vegetation (Caatinga) are part of animals’ diet that transit through the areas and consume the vegetal biomass found in trees and shrubs or deposited on the soil. A major problem in these regions are the producers create an excessive number of animals in small areas, leading to the overgrazing which reduces the reproductive capacity of the plants. That in turn entails the reduction of the accumulation of soil organic matter that linked directly to the production and deposition of biomass on the soil. Thus, our objective was to evaluate the impact of livestock farming on organic matter input in Brazilian semiarid soils. The collections carried out in the land uses: preserved native vegetation (PV), degraded native vegetation (DV) managed for 36 years and pasture cultivated with Cenchrus ciliaris for 40 years, both uses are on Acrisol. The soil was sampled in the 0-20 cm layer, the samples were air-dried and the organic matter contents were determined by the Yeomans and Bremner method. The soil organic matter stock was 47.6, 26.6, 28.1 Mg ha-1 for PV, DV and CC, respectively. The reduction in soil organic matter input from livestock was on average 44% and 41% for DV and CC. To minimize the impacts of livestock on the soil organic matter strategies such as pasture enrichment, sustainable management of native vegetation, as well as sustainable agroforestry production system, should be encouraged in semiarid regions.

Biography:

Degree in Agronomic Engineering from the Federal University of Pelotas (1994), a master’s degree in Soil Science from the Federal University of Rio Grande do Sul (1997) and a PhD in Soil Science from the Federal University of Rio Grande do Sul (2002). I work in the area of Agronomy, with emphasis on soil chemistry, working mainly in the following subjects: aluminum, corn, soil, bioassays and silicon. She is currently a researcher at the Center for Agricultural Research in the Semi-Arid Tropics, in the area of Soil Management and Conservation, developing studies with inventory and dynamics of carbon flow and technologies for low carbon agriculture.