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Cultivated fields are repeatedly affected by the impacts of agricultural machinery. Because the agricultural machines in use have different masses and sizes, however, the traffic-induced load inputs are unequally distributed across a field. Currently, the knowledge about spatial distributions of the amount of wheel passes, loads and stresses by farm vehicles is limited. To-date, no model exists, that will enable automated mapping of the spatially distributed intensities of field traffic. To close this gap, the Field Traffic Model (FiTraM) was developed. It calculates the tracks of each tyre based on routes, e.g. dGPS-recordings, in spatially explicit forms. Furthermore, the presented model provides spatial information about the distribution of field traffic intensities such as the number of wheel passes, wheel load and stress inputs. It also considers the changes in wheel load, e.g. caused by payload changes during harvest and by lifting attached implements. The functionality of the model will be demonstrated by calculating the wheel loads, mean contact area stresses and wheel pass frequencies by modelling three typical work processes (ploughing, sowing and harvesting) and a validation dataset for analysing spatial deviations during turning manoeuvres. The model is programmed with Python and Open-Source modules in order to provide access for a wide range of users. FiTraM enables the spatial analysis of agricultural traffic within individual fields and is designed to study the real traffic intensities, which has hardly been examined so far.

“The Anthropocene” currently serves as a framework to acknowledge global human influences on the earth systems. Different prominent authors call for geographers and especially physical geographers to intensify their involvement in the discussions on the theme. A bibliometric analysis shows that geographers are already one of the leading contributors to the keyword Anthropocene in journal articles. While we generally support the standpoint of increased engagement with the topic, we want to emphasize that we need to do more than only attaching the “Anthropocene” label to our daily research practice. A critical engagement with and reflection of the research questions and contexts is needed to play a vital role as discussant in the debate. We should take advantage of the diverse themes, topics and viewpoints of our subject by actively following a more critical approach to our research practices in order to find those geographic ties that join us and our discipline and that enable us to contribute more substantially to the Anthropocene debate.

Agricultural management is a key force affecting soil processes and functions. Triggered by biophysical constraints as well as rapid structural and technological developments, new management practices are emerging with largely unknown impacts on soil processes and functions. This impedes assessments of the potential of such emerging practices for sustainable intensification, a paradigm coined to address the growing demand for food and nonfood products. In terms of soil management, sustainable intensification means that soil productivity is increased while other soil functions and services, such as carbon storage and habitat for organisms, are simultaneously maintained or even improved. In this paper we provide an overview of research challenges to better understand how emerging soil management practices affect soil processes and functions. We distinguish four categories of soil management practices: spatial arrangements of cropping systems, crops and rotations, mechanical pressures, and inputs into the soil. Key research needs identified for each include nutrient efficiency in agroforestry versus conventional cropping systems, soil-rhizosphere microbiome elucidation to understand the interacting roles of crops and rotations, the effects of soil compaction on soil–plant–atmosphere interactions, and the ecotoxicity of plastics, pharmaceuticals and other pollutants that are introduced into the soil. We establish an interdisciplinary, systemic approach to soil science and include cross-cutting research activities related to process modeling, data management, stakeholder interaction, sustainability assessment and governance. The identification of soil research challenges from the perspective of agricultural management facilitates cooperation between different scientific disciplines in the field of sustainable agricultural production.

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.

The increasing use of biogas, produced from energy crops like silage maize, is supposed to noticeably change the structures and patterns of agricultural landscapes in Europe. The main objective of our study is to quantify this assumed impact of intensive biogas production with the example of an agrarian landscape in Northern Germany. Therefore, we used three different datasets, Corine Land Cover (CLC), local agricultural statistics (Agrar-Struktur-Erhebung, ASE), and data on biogas power plants. Via kernel density analysis, we delineated impact zones which represent different levels of bioenergy-generated transformations of agrarian landscapes. We cross-checked the results by the analyses of the land cover and landscape pattern changes from 2000 to 2012 inside the impact zones. We found significant correlations between the installed electrical capacity (IC) and land cover changes. According to our findings, the landscape pattern of cropland&mdash, expressed via landscape metrics (mean patch size (MPS), total edge (TE), mean shape index (MSI), mean fractal dimension index (MFRACT)&mdash, increased and that of pastures decreased since the beginning of biogas production. Moreover, our study indicates that the increasing number of biogas power plants in certain areas is accompanied with a continuous reduction in crop diversity and a homogenization of land use in the same areas. We found maximum degrees of land use homogenisation in areas with highest IC. Our results show that a Kernel density map of the IC of biogas power plants might offer a suitable first indicator for monitoring and quantifying landscape change induced by biogas production.

Weathering pits form on various rock types worldwide and often contain unique ecosystems in periodically flooded or desiccated depressions. However, little is known about soil formation in such pits. Here, we investigated two weathering pits (WP1 and WP2) on the summit of Enchanted Rock, a granitic exfoliation dome in central Texas. We aimed at unravelling the origin of the parent material, evaluating evidence for dating the soil development, and identifying the major soil forming processes. We sampled five soil profile cores in each pit and analyzed diverse soil properties, such as C and N contents, pH, exchangeable cations, texture, and iron oxides. In addition, we performed energy dispersive X-ray spectroscopy and applied optically stimulated luminescence (OSL) and 14C dating analyses. Both pits were affected by redoximorphic features and organic matter accumulation (2.5 ± 1.4% C in the topsoil). WP1 revealed Na accumulation in the subsoil and pronounced translocation of clay minerals, which accumulated at the bottom (up to 50% clay in the subsoil, 13–34% in topsoil). Such processes were absent in WP2, in which clay contents and their variations were comparatively small (16–25%). Here, acidic and nutrient poor soil horizons (pH 4.0–4.4, 0.5–1.5% C, 4.1–4.6 mg kg−1P) alternated several times with nutrient rich and neutral soil horizons (pH 5.1–5.6, 2.0–2.5% C, 23–33 mg kg−1P). This phenomenon was observed down to the bottom of the pit. We conclude that the parent material for soil development consists of three sources: autochthonous material from in-situ weathering of the solid rock, granitic grus particles from upslope positions, and eolian sediments from the area surrounding Enchanted Rock. Phases of sedimentation may have alternated with phases of stability and topsoil formation, resulting in buried former topsoils. OSL dating revealed that sedimentation began not later than 5110 years ago in 42 cm depth of WP1 and 2290 years ago in 26 cm depth of WP2. Due to contamination by younger carbon, 14C dates underestimate the beginning of soil development. The intensity of post sedimentary soil forming processes (clay mineral translocation, sodium enrichment, ferrolysis, organic matter accumulation) depends on the age of the pit and on its morphology, i.e. on the possibility of water and dissolved substances running off.

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.

Conservation agriculture may lead to increased penetration resistance due to soil compaction. To loosen the topsoil and lower the compaction, one-time inversion tillage (OTIT) is a measure frequently used in conservation agriculture. However, the duration of the positive effects of this measure on penetration resistance is sparsely known. Therefore, the aim of this study was to analyze the spatio-temporal behavior of penetration resistance after OTIT as an indicator for soil compaction. A field subdivided into three differently tilled plots (conventional tillage with moldboard plough to 30 cm depth (CT), reduced tillage with chisel plough to 25 cm depth (RT1) and reduced tillage with disk harrow to 10 cm depth (RT2)) served as study area. In 2014, the entire field was tilled by moldboard plough and penetration resistance was recorded in the following 5 years. The results showed that OTIT reduced the penetration resistance in both RT-plots and led to an approximation in all three plots. However, after 18 (RT2) and 30 months (RT1), the differences in penetration resistance were higher (p &lt, 0.01) in both RT-plots compared to CT. Consequently, OTIT can effectively remove the compacted layer developed in conservation agriculture. However, the lasting effect seems to be relatively short.

Avoiding soil compaction is one of the objectives to ensure sustainable agriculture. Subsoil compaction in particular can be irreversible. Frequent passages by (increasingly heavy) agricultural machinery are one trigger for compaction. The aim of this work is to map and analyze the extent of traffic intensity over four years. The analysis is made for complete seasons and individual operations. The traffic intensity is distinguished into areas with more than five wheel passes, more than 5 Mg and 3 Mg wheel load. From 2014 to 2018, 63 work processes on a field were recorded and the wheel load and wheel passes were modeled spatially with FiTraM. Between 82% (winter wheat) and 100% (sugar beet) of the total infield area is trafficked during a season. The sugar beet season has the highest intensities. High intensities of more than five wheel passes and more than 5 Mg wheel load occur mainly during harvests in the headland. At wheel load &ge, 3 Mg, soil tillage also stresses the headland. In summary, no work process stays below one of the upper thresholds set. Based on the results, the importance of a soil-conserving management becomes obvious in order to secure the soil for agriculture in a sustainable way.

Soil erosion by water is one of the main soil degradation processes worldwide, which leads to declines in natural soil fertility and productivity especially on arable land. Despite advances in soil erosion modelling, the effects of compacted tramlines are usually not considered. However, tramlines noticeably contribute to the amount of soil eroded inside a field. To quantify these effects we incorporated high-resolution spatial tramline data into modelling. For simulation, the process-based soil erosion model EROSION3D has been applied on different fields for a single rainfall event. To find a reasonable balance between computing time and prediction quality, different grid cell sizes (5, 1, and 0.5 m) were used and modelling results were compared against measured soil loss. We found that (i) grid-based models like E3D are able to integrate tramlines, (ii) the share of measured erosion between tramline and cultivated areas fits well with measurements for resolution &le, 1 m, (iii) tramline erosion showed a high dependency to the slope angle and (iv) soil loss and runoff are generated quicker within tramlines during the event. The results indicate that the integration of tramlines in soil erosion modelling improves the spatial prediction accuracy, and therefore, can be important for soil conservation planning.

Soil compaction caused by field traffic is one of the main threats to agricultural landscapes. Compacted soils have a reduced hydraulic conductivity, lower plant growth and increased surface runoff resulting in numerous environmental issues such as increased nutrient leaching and flood risk. Mitigating soil compaction, therefore, is a major goal for a sustainable agriculture and environmental protection. To prevent undesirable effects of field traffic, it is essential to know where and when soil compaction may occur. This study developed a model for soil compaction risk assessment of arable soils at regional scale. A combination of (i) soil, weather, crop type and machinery information; (ii) a soil moisture model and (iii) soil compaction models forms the SaSCiA-model (Spatially explicit Soil Compaction risk Assessment). The SaSCiA-model computes daily maps of soil compaction risk and associated area statistics for varying depths at actual field conditions and for entire regions. Applications with open access data in two different study areas in northern Germany demonstrated the model’s applicability. Soil compaction risks strongly varied in space and time throughout the year. SaSCiA allows a detailed spatio-temporal analysis of soil compaction risk at the regional scale, which exceed those of currently available models. Applying SaSCiA may support farmers, stakeholders and consultants in making decision for a more sustainable agriculture.

The present study analyzes a short-term observation of a newly created nature conservation area. The aim was to investigate different effects of grazing by cattle and, otherwise, the frequent mowing on the development of nutrient contents of soils. The results are typical for the strong sandy Weichselian outwash plain in the north of Central Europe (Schleswig-Holstein, Germany). Two neighboring testing areas of different use and sowed with an agricultural grass were observed for more than two years. The first area had been grazed intensively by cattle and the other one had been mowed twice a year. During this time, several nutrients and other soil parameters have been analyzed at regular intervals. Furthermore, we made observations about soil compaction and the succession of vegetation. The results show a stronger reduction especially of nitrogenous nutrients on the mowing area (-25%). In contrast, on the grazing area, the contents of nitrogen doubled during two growing seasons (+125%). However, a high atmospheric input of nitrogen strengthened the result. Less conclusive were the results about the contents of potassium, phosphorus and SOM. Therefore, mowing could be advised, if quick results are required concerning the impoverishment of soils. Furthermore, the development of succession vegetation was quite different on both areas with the number of plant species 12% higher on the grazing area. However, long-term but non-intensive cattle-grazing must still be rated as an excellent method of maintenance for this type of cultural landscape. It corresponds with the centuries-old land-use practice in this type of landscape and promotes high level of biodiversity. Therefore, there is nothing that speaks against non-intensive grazing from the beginning on a newly created nature-protection area within a long-term conception of nature conservation. The removal of A horizons should be avoided as it damages Holocene soil profies and has only short-term effects.