Compressibility and elasticity of a Vertissol affected by the intensity of grazing cattle/Compressibilidade e elasticidade de um Vertissolo afetado pela intensidade de pastejo bovino

• Published in: Ciência rural Vol. 44; no. 2; p. 283
• Main Authors: Capurro, Enrique Perez Gomar, Secco, Deonir, Reichert, Jose Miguel, Reinert, Dalvan Jose
• Format: Journal Article
• Language: Spanish
• Published: Universidade Federal de Santa Maria 01.02.2014
• Subjects: Analysis; Beef cattle; Soil structure
• ISSN: 0103-8478; 1678-4596

The supply of pasture quantity and quality in areas of native grassland is goal of ranchers. In this study we evaluated the impact of three grazing intensities by beef cattle in an area of unspoilt countryside with improved white clover and red cloveron soil bulk density (Bd), pre-consolidationpressure (sp), compression index (Ci) and the relaxation index (Ri) in a Vertisol derived from basalt. The experiment was conducted in an area of unspoilt countryside with improved white clover and red clover, subjected to three intensities of grazing, located in the experimental field of INIA Glencoe, in the Centre-North of Uruguay (Latitude: 32°41'S and Longitude: 56°16W). The soil has a depth of 0.92m, clayey silt (0.58kg [kg.sup.-1] clay) and has granular structure. The intensity of grazing configured the treatments: no grazing (SP), grazing with low load (consisting of grazing animals per hectare from 20 to approximately 385kg of body weight, during 4 days) (PCB) and grazing with high load (40 animals per hectare of approximately 385kg live weight, during 4 days) (PCA). Statistical analysis consisted of comparing averages of Bd, sp, Ci and Ri in the three soil treatments by Student's t test at 5% of significance. PCA caused no increase in relation to the Ds SP nor significant changes op and Ic, indicating that the bulk of the organic material provided on the surface of Vertisoil high load bearing capacity, low compaction susceptibility and high elasticity of the soil. The most superficial layer of Ri with respect to subsurface conditioned more resilient deformation, because the PCA were no significant changes in op and Ic against the SP and PCB.