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Nikolaus J. Kuhn   Professor  Other 
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Nikolaus J. Kuhn published an article in August 2018.
Top co-authors See all
Nikolaus J Kuhn

78 shared publications

Department of Environmental Sciences, Physical Geography and Environmental Change, Klingelbergstrasse 27, 4056 Basel, Switzerland

Philip Greenwood

12 shared publications

Geography, College of Life and Environmental Sciences; University of Exeter; Exeter EX4 4RJ UK

Kiran Dhanjal-Adams

11 shared publications

School of Biological Sciences; University of Queensland; Brisbane Queensland Australia

Yaxian Hu

7 shared publications

Wolfgang Fister

5 shared publications

78
Publications
36
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299
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Publication Record
Distribution of Articles published per year 
(2002 - 2017)
Total number of journals
published in
 
26
 
Publications See all
Article 0 Reads 0 Citations Evaluating the carbon sequestration potential of volcanic soils in South Iceland after birch afforestation Matthias Hunziker, Olafur Arnalds, Nikolaus J. Kuhn Published: 06 August 2018
SOIL Discussions, doi: 10.5194/soil-2018-26
DOI See at publisher website ABS Show/hide abstract
Afforestation is a strategy to sequester atmospheric carbon in the terrestrial system and to enhance ecosystem services. Iceland's large areas of formerly vegetated and now degraded ecosystems therefore have a high potential to act as carbon sinks. Consequently, the ecological restoration of these landscape systems is part of climate mitigation programs supported by the Icelandic government. The aim of this study was to explore the change of the soil organic carbon (SOC) pools and to estimate the SOC sequestration potential during the re-establishment of birch forest on severely degraded land. Differently aged afforested mountain birch sites (15, 20, 25 and 50 years) were compared with sites of severely degraded land, naturally growing remnants of mountain birch woodland and grasslands which were re-vegetated using fertilizer and grass seeds 50 years ago. The soil was sampled to estimate the SOC stocks and for physical fractionation to characterize the quality of the SOC. The results of our study show that the severely degraded soils can potentially sequester an additional 20tCha&minus;1 (0&ndash;30cm) to reach the SOC stock of naturally growing birch woodlands. After 50 years of birch growth, the SOC stock is lower than that of naturally growing birch woodland. Hence, afforested stands can sequester additional SOC after 50 years of birch growth. The SOC fractionation revealed that at all tested sites most of the carbon was stored in the <63μm fraction. However, the particulate organic matter (POM) fraction was enriched most during the succession of afforested mountain birch stands (+12tPOM-Cha&minus;1). The study also found a doubling of the dissolved organic carbon (DOC) concentration after 50 years of birch growth. Therefore, we assume that carbon deriving from the afforestation process is sequestered as labile SOC, which may be partly released to the atmosphere during the process of stabilization with the mineral soil phases in the future. Our results are limited in their scope since the selected sites do not fully reflect the heterogeneity of landscape evolution and the range of soil degradation conditions. As an alternative, we suggest using repeated plot measurements instead of space-for-time substitution approaches for testing C changes in severely degraded volcanic soils. Our findings clearly show that detailed measurements on the SOC quality are needed to estimate the SOC sequestration potential of restoration activities on severely degraded volcanic soils is needed, rather than only measuring SOC-concentration and SOC stocks.
Article 0 Reads 0 Citations Bioenergy crop induced changes in soil properties: A case study on Miscanthus fields in the Upper Rhine Region Yaxian Hu, Gerhard Schäfer, Joëlle Duplay, Nikolaus J. Kuhn Published: 26 July 2018
PLOS ONE, doi: 10.1371/journal.pone.0200901
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Biomass as a renewable energy source has become increasingly prevalent in Europe to comply with greenhouse gas emission targets. As one of the most efficient perennial bioenergy crops, there is great potential in the Upper Rhine Region to explore biomass utilization of Miscanthus to confront climate change and land use demand in the future. Yet, the impacts of Miscanthus cultivation on soil quality have not been adequately explored. This study investigated the soil profiles of five- and 20-year-old Miscanthus fields (1 m depth) as well as grassland for reference in eastern France and Switzerland. The soil organic carbon (SOC) concentrations and δ13C compositions of four soil layers (0–10 cm, 10–40 cm, 40–70 cm and 70–100 cm) were determined. The CO2 emission rates of the topsoil were monitored for 42 days. Our results showed that Miscanthus, in general, could increase the SOC stocks compared to grassland, but the benefits of SOC sequestration were constrained to the surface soil. Isotopically, the Miscanthus-derived SOC ranged from 69% in the top 10 cm of soil down to only 7% in the 70 cm to 100 cm layer. This result raises the risk of overestimating the total net benefits of Miscanthus cultivation, when simply using the greater SOC stocks near the surface soil to represent the SOC-depleted deep soil layers. The Miscanthus fields had greater CO2 emissions, implying that the Miscanthus fields generated greater ecosystem respiration, rather than larger net ecosystem exchanges. Compared to the grassland soils, the surface soils of the Miscanthus fields tended to have a risk of acidification while having higher concentrations of phosphorus and potassium, calling for the inclusion of soil characteristics and SOC stability when evaluating the impacts of long-term Miscanthus cultivation on both current and future land use changes.
Article 4 Reads 2 Citations The invasive alien plant, Impatiens glandulifera (Himalayan Balsam), and increased soil erosion: causation or associatio... Philip Greenwood, Patrick Baumann, Simon Pulley, Nikolaus J.... Published: 04 June 2018
Journal of Soils and Sediments, doi: 10.1007/s11368-018-2041-0
DOI See at publisher website
Article 0 Reads 0 Citations Local soil quality assessment of north-central Namibia: integrating farmers' and technical knowledge Brice Prudat, Lena Bloemertz, Nikolaus J. Kuhn Published: 07 February 2018
SOIL, doi: 10.5194/soil-4-47-2018
DOI See at publisher website ABS Show/hide abstract
Soil degradation is a major threat for farmers of semi-arid north-central Namibia. Soil conservation practices can be promoted by the development of soil quality (SQ) evaluation toolboxes that provide ways to evaluate soil degradation. However, such toolboxes must be adapted to local conditions to reach farmers. Based on qualitative (interviews and soil descriptions) and quantitative (laboratory analyses) data, we developed a set of SQ indicators relevant for our study area that integrates farmers' field experiences (FFEs) and technical knowledge. We suggest using participatory mapping to delineate soil units (Oshikwanyama soil units, KwSUs) based on FFEs, which highlight mostly soil properties that integrate long-term productivity and soil hydrological characteristics (i.e. internal SQ). The actual SQ evaluation of a location depends on the KwSU described and is thereafter assessed by field soil texture (i.e. chemical fertility potential) and by soil colour shade (i.e. SOC status). This three-level information aims to reveal SQ improvement potential by comparing, for any location, (a) estimated clay content against median clay content (specific to KwSU) and (b) soil organic status against calculated optimal values (depends on clay content). The combination of farmers' and technical assessment cumulates advantages of both systems of knowledge, namely the integrated long-term knowledge of the farmers and a short- and medium-term SQ status assessment. The toolbox is a suggestion for evaluating SQ and aims to help farmers, rural development planners and researchers from all fields of studies understanding SQ issues in north-central Namibia. This suggested SQ toolbox is adapted to a restricted area of north-central Namibia, but similar tools could be developed in most areas where small-scale agriculture prevails.
BOOK-CHAPTER 0 Reads 0 Citations Assessing Badland Sediment Sources Using Unmanned Aerial Vehicles Juliane Krenz, Nikolaus J. Kuhn Published: 01 January 2018
Badlands Dynamics in a Context of Global Change, doi: 10.1016/b978-0-12-813054-4.00008-3
DOI See at publisher website
BOOK-CHAPTER 0 Reads 0 Citations List of Contributors Valerio Amici, Giovanni Bacaro, Francesco Brogi, Adolfo Calv... Published: 01 January 2018
Badlands Dynamics in a Context of Global Change, doi: 10.1016/b978-0-12-813054-4.01002-9
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