Pasture Degradation in Atlantic Forest Biome: Diagnostic By on-Farm Assessment and Soil Atributtes

Objective: This study aimed to distinguish the levels of pasture degradation (PD) using on-farm methods and soil attributes, mainly physical attributes. Theoretical framework: There is a vast area of ​​degraded pastures in Brazil; more than half of these pastures have some degree of degradation. The classification of pasture degradation levels, such as mild, moderate, and severe, based on soil quality indicators, by biome, region, and soil type, is still scarce. There is a need to classify these pasture degradation levels based on practical soil and pasture quality indicators for the middle Paraíba Valley region of southern Brazil, with the aim of guiding producers in the recovery of degraded pastures, as well as supporting public policies. Method: A classification of pasture degradation levels was performed in Urochloa brizantha pastures on Haplic Cambisol, in hills in the middle third of the slope. Plots of 500 m2 were established, and practical indicators of soil and pasture quality were measured in these plots for the classification of pasture degradation levels. The means of the soil and pasture quality indicators in the classification of pasture degradation levels were statistically analyzed using mean comparison tests and multivariate statistics. Results and conclusions: Results and conclusions: It was observed that practical indicators of soil and pasture quality allow for the classification of pasture degradation levels into three levels: mild, moderate, and severe. The combination of field assessments and soil attributes proved to be an adequate and efficient approach for diagnosing pasture degradation in the Atlantic Forest biome. Both strategies provided useful and complementary information to elucidate how the degradation process occurs. In this sense, field assessments were more efficient than the selected soil attributes in distinguishing pasture degradation levels (PD), since three PD levels were identified by forage cover and visible root depth, in contrast to only two levels defined by soil attributes. However, it was only through Principal Component Analysis (PCA) that all the PD levels studied were divided into four distinct groups. Research implications: The results serve as benchmarks to guide pasture recovery or renovation, as well as sustainable pasture management. Furthermore, they can support the public policy of the national program for converting degraded pastures to sustainable agriculture in the mid-Paraíba Valley region of southern Brazil. Since pasture degradation is widespread among rural properties, the advances obtained by this research can empower rural producers and extension agents to monitor and diagnose the level of pasture degradation in the Atlantic Forest biome. With a small investment in materials and a robust protocol, field assessment can make degradation more evident to rural producers, promoting the engagement and reach necessary to prevent degradation, recover already degraded areas, and seek soil conservation. Originality/value: Pasture degradation was best described by forage cover and visible root depth; weeds can protect the soil, especially during the wet season in areas with rugged terrain; the Rapid Soil Structure Diagnosis (DRES) method provided information by evaluating the role of roots in soil aggregation.