The concept of a no-tillage system (NTS), or "Sistema Plantio Direto," was established in Brazil from the evolution of no-tillage (NT) or "Plantio Direto," given the edaphoclimatic conditions and the need to promote chemical, physical and biological improvements in cultivated soils. While "Plantio Direto" is a conservationist practice, "Sistema Plantio Direto" presents itself as an agricultural production system based on the simultaneous adoption of minimum soil disturbance, maintenance of permanent soil cover and crop rotation. This study reviews the concepts of "Plantio Direto" and "Sistema Plantio Direto" in the Brazilian literature and uses two case studies in Paraná State to demonstrate the practical implications of these concepts. These two terms and their variations are recurrent themes in Brazilian scientific research and the professional environment, and may occur erroneously, hindering their adoption, results and implications. Regarding the "Sistema Plantio Direto," we highlight the need to clarify the concepts of its basic practices to parameterize and characterize this process. The definition of crop rotation, for example, requires limits on the number of species along a given time scale, thus enabling their identification. Regarding the case studies, most grain crops conducted in Paraná State did not adopt the "Sistema Plantio Direto," mainly neglecting the component of crop rotation. Nevertheless, the use of the "no-tillage system participatory quality index" (PQI) tool can contribute to the assessment and monitoring of the quality of the "Sistema Plantio Direto." However, it requires adjustments to differentiate the "Sistema Plantio Direto" from the "Plantio Direto.

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Objetivou-se avaliar os atributos químicos de solos em área com adoção de sistemas integrados de produção agropecuária de longa duração, comparado a uso do solo com pastagem e mata nativa. O estudo foi realizado em áreas manejadas de cinco estabelecimentos agropecuários do Sudoeste do Paraná, que adotaram o sistema de integração lavoura-pecuária (ILP) e receberam orientações de práticas de manejo de solo por 12 anos. Em cada localidade foram amostrados solos sob ILP, pastagem (PV) e mata nativa (MN) para a determinação do pH, dos teores de Ca, Mg, K, P, da saturação por bases (V%) e alumínio (m%) e do teor de matéria orgânica do solo (MOS). A adoção do sistema de ILP, proporcionou níveis adequados dos atributos químicos dos solos, principalmente para pH, V%, m%, Ca, Mg, K e MOS. Identificaram-se, ainda, casos de uso de elevadas doses de cama de aviário como fertilizante, com altos teores de P na superfície do solo, os quais podem gerar problemas ambientais.

Crop-livestock system (CLS) based on summer crops, as soybean and corn, in rotation with oat+ryegrass pasture in winter for dairy products, is the most adopted productive system at the southern region of Paraná, Brazil. Although its management needs to be evaluated, in order to improve its sustainability. In this sense, this study aimed to measure the impacts of management practices of five smallholder farms on soil quality, considering the soil use history. Soil samples were collected to determine soil bulk density (BD), macroporosity (Ma), microporosity (Mi), weighted mean diameter (WMD) in each area under CLS, summer pasture and native forest, as a control. Areas under CLS altered soil physical attributes (higher BD and Mi and lower Ma) in relation to the non-anthropized area as a consequence of animal trampling. However, the conservationist management adopted, with the soil cover maintenance along with years of minimum tillage, the use of grasses with aggressive roots along with the winter period, did not culminate in limitations of soil functions. Soil structure dynamics needs to be investigated to better determine the biological and physical influence on the formation of soil aggregation.