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No-till (NT) is a conservation system that improves the hydrological regime of agricultural slopes by providing greater surface protection and benefits to the physical and hydrological properties of soils. However, the isolated use of NT is not enough to control runoff and its associated degradation processes. Therefore, this study aimed to evaluate the runoff of agricultural slopes under NT under different runoff control conditions by monitoring 63 rainfall events in two 2.4-ha zero-order catchments and 27 rainfall events in four 0.6-ha macroplots. The catchments are paired and similar in terms of the type of soil and relief, but different regarding the presence of terraces. The macroplots have different soil and crop management systems. By using monitoring techniques, the hyetographs and hydrographs revealed the influence of the different types of management on the catchments and macroplots and allowed rainfall characteristics, runoff volume, runoff coefficients, water infiltration, peak runoff, response times, and curve number to be analysed. The terraces positively affected the NT and controlled runoff and related variables, in addition to infiltration significantly increasing and runoff reducing in the terraced catchment. All the hydrological information assessed pointed to the positive effects provided by the presence of the terraces. The results in the macroplots showed that high amounts of phytomass and/or chiselling do not control runoff and its correlated variables in medium and high magnitude events. The study concludes by underlining the need for additional measures to control runoff (terraces), even in areas under NT and with high phytomass production. Additionally, the study emphasizes the importance of monitoring at the catchment scale to better understand the hydrological behaviour of agricultural areas and provide the necessary parameters to effectively control runoff.

No-tillage is a soil management practice that results in reduced soil losses when compared to conventional tillage systems. However, when this practice is overly simplified, it may lead, over the years, to higher levels of soil loss than expected. In this context, this study sought to compare the rates of long-term soil redistribution on three hillslopes used for grain production under different soil management on deep weathered soils (Ferralsols) in southern Brazil. Soil samples were collected along three transects in different hillslopes characterized by either no-tillage or conventional tillage. Cs-137 inventories were used to estimate the soil redistribution rates based on Mass Balance Model-2. The results indicate that along the three slopes and during the last five decades, changes in soil management impacted the patterns of soil erosion in the landscape, showing the occurrence of significant soil loss in the upper and PAGE 2 backslope segments, and deposition in the lower parts of the three hillslopes studied. Even with no-tillage, erosion has continued to occur, although at lower rates when compared to conventional tillage. The use of the 137 Cs marker associated with the Mass Balance Model-2 (MBM-2) conversion model provided an effective tool for estimating soil redistribution rates under different management systems. Although the introduction of no-tillage in the last 28 years has reduced erosion rates, these processes remain significant and the implementation of additional runoff and/or erosion control practices is recommended in order to keep erosion rates at sustainable levels.

No-till (NT) is a soil management system designed to protect soil resources from water erosion and provide numerous benefits compared to conventional tillage through the increase of organic matter inputs into the soil. However, NT in isolation is not sufficient to control erosion processes caused by an excessive production of surface runoff. This study evaluated soil losses on agricultural hillslopes under no-till characterized by contrasted water, soil, and crop management conditions. To this end, water and soil losses were monitored between 2014 and 2018 at two scales, including four macroplots (0.6 ha; 27 events) and two paired zero-order catchments (2.4 ha; 63 events). The resulting dataset covered a wide range of rainfall conditions that occurred in contrasted soil, crop, and runoff management conditions.