Humans have greatly impacted the processes and intensities of erosion, sediment transport and storage since the introduction of agriculture. In many regions around the world, accelerated floodplain sedimentation can be related to increases in human pressure on the environment. However, the relation between the intensity of anthropogenic disturbance and the magnitude of change in fluvial sediment dynamics is not straightforward and often non-linear. Here, we review a number of case studies from contrasting environmental settings in the European loess belt, the Eastern Mediterranean mountain ranges and the eastern USA. Detailed field-based sediment archive studies and sediment budgets covering time periods ranging from 200 to over 5000 year, as well as the use of pollen and sediment provenance techniques, show that no overarching concept of changes in floodplain sedimentation following anthropogenic disturbance can be established. Slope-channel (dis)connectivity controls the existence of thresholds or tipping points that need to be crossed before significant changes in downstream sediment dynamics are recorded following human impact. This coupling can be related to characteristics of human pressure such as its duration, intensity and spatial patterns, but also to the geomorphic and tectonic setting. Furthermore, internal feedback mechanisms, such as those between erosion and soil thickness, further complicate the story. All these factors controlling the propagation of sediment from eroding hillslopes to river channels vary between regions. Hence, only unique patterns of fluvial geomorphic response can be identified. As a result, unravelling the human impact from current-day sediment archives and predicting the impact of future human disturbances on fluvial sediment dynamics remain a major challenge. This has important implications for interpreting contemporary sediment yields as well as downstream sediment records in large floodplains, deltas and the marine environment, in terms of changes in the drivers of environmental change.

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The western Taurus mountains, southwest Turkey, comprise a diverse set of landscape zones that are characterized by great altitude variations. This article focuses on the agricultural so-called marginal highlands within this mountainous region. Large parts of the uplands are labeled “marginal” nowadays as they are not regarded as highly productive in terms of agricultural output or permanent occupation. Three decades of interdisciplinary research within the Sagalassos Archaeological Research Project (KU Leuven) have provided an enormous amount of archaeological, bioarchaeological, and geoarchaeological datasets that will be brought together in this article to explore diachronic patterns in human-environmental interactions within these areas. The study demonstrates not only the archaeological value of a highland area, but its vulnerability for human impact as well. The changing environments both naturally and sociopolitically favored a more resilient behavior of the human groups within the highlands.

Most contemporary crop yield models focus on a small time window, operate on a plot location, or do not include the effects of the changing environment, which makes it difficult to use these models to assess the agricultural sustainability for past societies. In this study, adaptions were made to the agronomic AquaCrop model. This adapted model was ran to cover the last 4000 years to simulate the impact of climate and land cover changes, as well as soil dynamics, on the productivity of winter wheat crops for a Mediterranean mountain environment in SW Turkey. AquaCrop has been made spatially explicit, which allows hydrological interactions between different landscape positions, whilst computational time is kept limited by implementing parallelisation schemes on a supercomputer. The adapted model was calibrated and validated using crop and soil information sampled during the 2015 and 2016 harvest periods. Simulated crop yields for the last 4000 years show the strong control of precipitation, while changes in soil thickness following erosion, and to lesser extent re-infiltration of runoff along a slope catena also have a significant impact on crop yield. The latter is especially important in the valleys, where soil and water accumulate. The model results also show that water export to the central valley strongly increased (up to four times) following deforestation and the resulting soil erosion on the hillslopes, turning it into a marsh and rendering it unsuitable for crop cultivation.

To investigate the potential impact on ground- or surface water of natural radionuclides present in waste disposed onto landfills, activity concentrations in leachates, waste water treatment plant discharge and groundwater of several landfills in Belgium have been analysed. 16 currently in operation landfills for hazardous and non-hazardous waste and 10 legacy landfills have been investigated. Results indicate the presence of a slightly enhanced concentration of uranium and other radionuclides in some leachates of landfills in operation. For legacy landfills, enhanced uranium concentration is also observed in some groundwater wells. The presence of uranium in groundwater around landfills is always accompanied by a contamination with other heavy metals and chlorides. No clear linear correlation between concentration of uranium and other metals could be found however. Isotopic ratio between U-238 and U-234 has been calculated in the different water matrices and is close to one in contaminated groundwater, probably indicating an anthropogenic contamination. In all cases, the concentrations of natural radionuclides do not reach values of concern from radiation protection point of view.