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Process‐based model ling has long been used as a well‐suited tool to simulate soil erosion. Despite a large number of scientific articles that emphasize the role of compacted tramlines for soil erosion and surficial nutrient transport, no study exists that integrates these artificial structures into process‐based modelling at catchment scales. Thus, this study aims to quantify the effects of tramline compaction on soil erosion dynamics within a catchment. For this reason, high‐resolution spatial data (1 × 1 m) have been incorporated into the model EROSION 3D, which was used, calibrated, and tested for a soil erosion event with measured discharge and soil loss data. To quantify the contribution of tramlines to soil erosion, two different model parameterizations have been used: the tramline parameterization (TLP) and the common model parameterization (CP) that disregards the tramlines. The results reveal that: (i) the parameterization of tramlines improved model outcomes; (ii) tramlines significantly contribute to overall soil loss and sediment entrance into the channel network; (iii) the bulk density of tramlines is the most important driver of increases in soil erosion and runoff. Moreover, our investigation suggests that the impact of compacted tramlines have long been underestimated in soil erosion modelling and can assist in the assessment of surficial flow path connectivity. Thus, the integration of tramlines into soil erosion modeling is important for the implementation of adequate soil conservation and water protection measures., Federal Ministry of Education and Research (within the BonaRes Framework) http://dx.doi.org/10.13039/501100002347, https://doi.org/10.5281/zenodo.5153427

In addition to various positive aspects, long-term reduced tillage may cause disadvantages such as increased weed pressure and soil compaction. Thus, single inversion tillage is customarily used for overcoming these drawbacks; however, the effects on the enhanced soil functions are unknown. The main objective of this study was therefore to assess whether improved soil physical properties following long-term reduced tillage remain after one-time inversion tillage by mouldboard plough. The study was undertaken on a silt loam field in Lower Saxony, Germany. Since 1996, this field has been subdivided into three treatments; one was managed conventionally using a mouldboard plough (CT), while on the others a chisel plough (RT1) and a disc harrow (RT2) were employed. In October 2014, the entire field was mouldboard ploughed. The following year, four field campaigns were conducted to compare the soil physical properties of the continuously conventional tilled plot with those affected by one-time inversion tillage (RT1 and RT2). Dry bulk density (DBD), saturated hydraulic conductivity (Ks) and infiltration rate [K(h)] were analysed in untrafficked and trafficked areas in each plot. There were clear differences between CT and RT. At all sampling dates, both RT plots had higher Ks and K(h) compared with CT. These differences also occurred to some extent on the trafficked areas. This suggests that improved soil hydraulic properties remained after one-time inversion tillage of a long-term reduced tilled field. Thus, one-time inversion tillage may offer a suitable measure for overcoming some of the main disadvantages associated with long-term reduced tillage, while preserving the positive effects on soil physical properties.

Measuring penetration resistance (PR) is a common technique for evaluating the effects of field management on soils. This study focuses on the effects of long-term tillage on the spatial distribution of PR, comparing reduced and conventional tillage (CT) practices. The study site, located in Lower Saxony (Germany), has been subdivided into three plots, with one plot having been managed conventionally, whereas reduced tillage (RT) practices have been applied to the other two. In total, PR was measured at 63 randomly selected points. The PR data were stepwise interpolated using kriging with external drift. Core samples have been taken at 20 additional sites. The results show significant differences in PR between the different tillage practices. Within the conventionally managed plot, PR ranges to 2.3 MPa less in the topsoil than under RT. However, measured saturated hydraulic conductivity and amount of biopores at the depth of 30–35 cm are significantly greater under RT, indicating improved soil properties under RT. Comparisons between the headlands (HL) and the inner field point out the effects of intense field traffic in the HL, where maximum PR values of about 6 MPa have been measured. The spatial prediction of PR values show that long-term effects of different tillage practices result in clearly structured patterns between CT and RT and the HL. Combining extensive PR measurements and point measurements of additional soil properties supports an adequate interpretation of PR data and can lead to fieldwide derivation of soil functions influenced by field management.