Modeling and quantification of soil compaction promoted by animal trampling in an integrated crop–livestock system

Abstract

At critical levels, animal trampling can physically degrade soil, leading to the loss of sustainability of agricultural production. Therefore, it is becomes necessary to model and quantify the soil compaction potential. In this context, the objective was to evaluate the occurrence of soil compaction promoted by animal trampling in crop-livestock integration system (ICL). The study was conducted in a field at Centro Tecnológico da Comigo in the municipality of Rio Verde, Goias state, Brazil, during the agricultural off-season. The experimental area was composed of 1.97 ha, which was equally divided into eight paddocks. Soil was sampled before the grazing phase and after each of four grazing cycles. The compressive behavior of the soil was evaluated by determining the pre-consolidation and critical pressures. The results showed that only the first cycle of grazing showed additional compaction in 14.59% of samples. No critical compaction was observed in the evaluated area. Animal trampling under the studied conditions is not responsible for the dissemination of structural soil degradation in crop-livestock integration systems and may contribute to physical improvement resulting from biological soil loosening.

Crop-Livestock Integration Improves Physical Soil, Agronomic and Environmental Aspects in Soybean Cultivation

“…For this reason, the results show that any restrictions on the use of B. brizantha as a cover crop are not associated with the morphology of this forage plant, but with the physiology of desiccation, particularly in relation to Xaraes palisadegrass, which was less efficient in this process than Paiaguas palisadegrass and ruziziensis grass [54]. Although B. brizantha cultivars are considered to be strategic tools for physical soil management [16,21,22], their use is somewhat resisted by farmers due to incorrect desiccation management, commonly associated with the difficulty of desiccation which, in turn, affects the sowing operation of crops in succession, in terms of the loss of the operational efficiency of the machinery.…”

“…So far, it is undeniable that this intensification of land use, provided by the adoption of crop-livestock integration after the summer crop (the first crop of the agricultural calendar) is sustainable because it is technically feasible and economically resilient because it diversifies production [4,6,39]; socially fair, by keeping human resources in the field, given the optimization and rational use of labor [40]; and environmentally correct [8], by: (i) promoting the sequestration of atmospheric carbon [26], (ii) biologically decompressing the soil, contributing to erosion control and restoring the hydrological cycle [16,21,22], (iii) suppressing diseases and weeds, reducing the use and selection of herbicide-resistant plants [41] and (iv) cycling nutrients, reducing the demand for synthetic fertilizers [23,28]. For these reasons, CLI has recently been used by the Brazilian government to define public policies on agricultural credit, deforestation control and greenhouse gas mitigation.…”

“…Xaraes and Brachiaria ruziziensis, in monocropping and intercropped with maize, as well as maize in monocropping (control/additional). In the subplots, there were two grass management systems: free growth and grazing simulation cutting, with the aim of quantifying the potential for structuring the soil by the root system and the grass cutting management (considering the possibility that when cut/grazed, there will be a high physiological response of regrowth and rooting), without the influence of animal trampling, which could cause additional compaction [16].…”

“…Compaction is a consequence of the compression of unsaturated soil when subjected to the pressures applied by machinery and animals [15,16] and is characterized as the greatest physical limitation to high crop productivity worldwide [17,18]. For this reason, the recovery of the soil's physical quality is of agricultural and environmental importance, especially in tropical regions, such as the Latossolos in Cerrrado [in the Brazilian Soil Classification System-Santos et al [19]; Oxisols in the USA Keys of Soil Taxonomy-Soil Survey Staff (2014); and Ferralsols in the World Reference Base for Soil Resources-IUSS Working Group WRB (2015)], in soils that are highly susceptible to compaction [13].…”

“…Crop-livestock integration (CLI), when associated with the cultivation of Brachiaria brizantha (syn. Urochloa), is a promising technique for biological soil loosening and improving the structural quality of the soil [16,[21][22][23], particularly in intensive agricultural production systems where machine traffic is intense [24]. Thus, the development of these plants can mitigate the deleterious effects caused to the soil structure [11].…”