Jannes Stolte
Senior Research Scientist
Biography
My long-term experience is on catchment hydrology, with emphasize on soil physical processes. I have performed studies on soil erosion in the Netherlands, China and Norway, and have co-developed and extensively tested a physical-based hydrological and soil erosion model. Event-based processes like flooding, gully erosion, and sediment and nutrient losses are the core of my work. I have analysed and defined; (i) measurement techniques for model parameters; (ii) field monitoring for quantification; (iii) model sensitivity analysis; (iv) defining measures for reducing erosion, flood risk and soil deterioration; (v) participatory approaches for selecting feasible measures; and (vi) quantification of selected land use strategies.
My scientific goal is to maintain good quality soil and reduce flood and erosion risk, with focus on soil functions and ecosystem services. There is a persuasive need for developing a thorough risk-based framework for assessing soil health. I believe that by implementing a land use strategy that uses the landscape for capturing and retaining water, overland flow will decrease, resulting in a decrease in flood and erosion risk. If, at the same time, agricultural practices focus on increase of organic matter and infiltration capacity, soil quality will increase as well as the ability of soil to perform its functions. Good-quality soils are necessary for the food, fibre and fuel of a growing population, making soils a shared resource that requires governance.
Abstract
Soil health assessments that integrate physical, chemical and biological indicators help the evaluation of soil functioning, provide a framework for monitoring soil degradation, guide land management activities and secure the delivery of soil ecosystem services. In this study, we assessed soil health by soil texture class on arable land in Southeast Norway and mid-Norway and between grassland and arable land in mid-Norway. We used descriptive statistics and the Welch t-test with unequal variance and Bonferroni corrections to compare a physical soil indicator (bulk density) and chemical indicators (organic matter, P-AL, K-AL, Ca-AL, Mg-AL, Na-AL and pH). We developed scoring curves from cumulative normal distribution functions on regional soil data for various soil indicators where climate, soil texture class and land use were considered. Our results show that for certain soil texture classes, average soil indicator values differed between pedo-climatic zones on arable land, but for others the difference was not significant. The variability between the pedo-climatic zones for these can be neglected, but for the ones that differ, the variability is important to consider when assessing soil health. Similarly, this was the case when comparing land use (grassland and arable land) for most soil indicators in mid-Norway. This finding illustrates the importance of addressing unique local conditions in soil health assessments. We propose aggregating similar soil texture classes where no differences are apparent when developing scoring curves. The sub-optimal levels of plant available nutrients (P-AL and K-AL) found in the soil in both pedo-climatic zones highlights the importance of suitable threshold values for targeted soil ecosystem services to ensure soil health and sustainable agricultural production. We also recommend prioritizing the most relevant soil ecosystem services to limit the number of soil indicators that need monitoring.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
