IDESSA Publications

In progress

Beilschmidt, C., Fober, T., Mattig, M., Seeger, B. (in prep.): Efficient Algorithms for Visual Clustering.

Dreber, N., van Rooyen, S.E., Kellner, K. (in prep.): Structural and compositional variation among differently managed woody savanna layers in South Africa's Molopo Bushveld.

Hess, B., et al. (in prep.): A multifunctional piosphere landscape generator (PioLaG) for grazing systems in southern African savannas.

Hess, B., et al. (in prep.): A multi-functional rangeland model for the simulation of cross-scale savanna vegetation dynamics in space and time.

Hesselbarth, M., Wiegand, K., Dreber, N., Kellner, K., Esser, D., Tsvuura, Z. (under review): Density-dependent spatial patterning of woody plants differs between a semi-arid and a mesic savanna in South Africa.

Higginbottom, T., Symeonakis, E., Meyer, H., van der Linden, S. (under review): Mapping Woody Cover in Semi-arid Savannahs using Multi-seasonal Composites from Landsat Data.

Meyer, H., Reudenbach, C., Hengl, T., Katurji, M., Nauss, T. (under review): Forward feature selection and target-oriented validation to improve performances of spatio-temporal machine learning applications.

Morgenthal, T., Meyer, H., Ludwig, M., Lezama Valdes, M., Nauss, T. (in prep): Spatio-temporal development of bush encroachment in the Molopo Area, South Africa.

Pillay, T., Ngcobo, S.P., Ward, D. (submitted): Fertilizer and fire influences biological nitrogen fixation and soil respiration in Acacia sieberiana.

Pillay, T., Ward, D. (submitted): Drought suppresses grass productivity while warming promotes tree performance in a savanna: implications from a rainfall and warming experiment.

Pillay, T., Ward, D. (submitted): Interactive effects of fire, fertilizer and grazing on an encroaching woody species: the importance of grass competition in limiting sapling growth and performance.

Pillay, T, Ward, D., Mureva, A., Cramer, M.D. (submitted): Soil, litter and plant dynamics across a rainfall gradient: the effects of fertilization and woody plant encroachment.

Schmidt, J., Meyer, H., Detsch, F., Nauss, T. (in prep): Satellite-based monitoring of hourly air temperature in South Africa.

Peer-reviewed publications

Accepted

Beilschmidt, C., Fober, T., Mattig, M., Seeger, B. (accepted): A Linear-Time Algorithm for the Aggregation and Visualization of Big Spatial Point Data. ACM GIS Conference.

2018

Ward, D., Trinogga, J., Wiegand, K., du Toit, J., Okubamichael, D., Reinsch, S., Schleicher, J. (2018): Large shrubs increase soil nutrients in a semi-arid savanna. Geoderma 310: 153-162.

2017

Accatino, F., Ward, D., Wiegand, K., De Michele, C. (2017): Carrying capacity in arid rangelands during droughts: the role of temporal and spatial thresholds. Animal, 11: 309-317.

Beilschmidt, C., Drönner, J., Mattig, M., Schmidt, M., Authmann, C., Niamir, A., [...], Seeger, B. (2017): VAT: A Scientific Toolbox for Interactive Geodata Exploration. Datenbank-Spektrum: 1-11.

Beilschmidt, C., Drönner, J., Mattig, M., Schmidt, M., Authmann, C., Niamir, A., Hickler, T., Seeger, B. (2017): Interactive Data Exploration for Geoscience. BTW Workshops 2017

Beilschmidt, C., Drönner, J., Mattig, M., Seeger, B. (2017): VAT: A System for Data-Driven Biodiversity Research. In: EDBT (pp. 546-549).

Beilschmidt, C., Fober, T., Mattig, M., Seeger, B. (2017): Quality Measures for Visual Point Clustering in Geospatial Mapping. In: International Symposium on Web and Wireless Geographical Information Systems (pp. 153-168). Springer.

Dreber, N., van Rooyen, S.E., Kellner, K. (2017): Relationship of plant diversity and bush cover in rangelands of a semi-arid Kalahari savanna, South Africa. African Journal of Ecology, DOI: 10.1111/aje.12425

Meyer, H., Drönner, J., Nauss, T. (2017b): Satellite-based high-resolution mapping of rainfall over southern Africa. Atmospheric Measurement Techniques 10: 2009-2019.

Meyer, H., Kühnlein, M., Reudenbach, C., Nauss, T. (2017): Revealing the potential of spectral and texture predictor variables in a neural network based rainfall retrieval technique. Remote Sensing Letters 8: 647-656

Mureva, A., Ward, D. (2017): Soil microbial biomass and functional diversity in shrub-encroached grasslands along a precipitation gradient. Pedobiologia - Journal of Soil Ecology 63: 37-45.

2016

Accatino, F., Wiegand, K., Ward, D., De Michele, C. (2016): Trees, grass, and fire in humid savannas - The importance of life history traits and spatial processes. Ecological Modelling 320: 135-144.

Harmse, C.J., Kellner, K., Dreber, N. (2016): Restoring productive rangelands: A comparative assessment of selective and non-selective chemical bush control in a semi-arid Kalahari savanna. Journal of Arid Environments 135: 39-49.

Ludwig, A., Meyer, H., Nauss, T. (2016): Automatic classification of Google Earth images for a larger scale monitoring of bush encroachment in South Africa. International Journal of Applied Earth Observation and Geoinformation 50: 89-94

Meyer, H., Kühnlein, M., Appelhans, T., Nauss, T. (2016): Comparison of four machine learning algorithms for their applicability in satellite-based optical rainfall retrievals. Atmospheric Research 169: 424-433.

Mureva, A., Ward, D. (2016): Spatial patterns of encroaching shrub species under different grazing regimes in a semi-arid savanna, eastern Karoo, South Africa. African Journal of Range and Forage Science, DOI : 10.2989/10220119.2016.1148775

2015

Authmann, C., Beilschmidt, C., Drönner, J., Mattig, M., Seeger, B. (2015): VAT: a system for visualizing, analyzing and transforming spatial data in science. Datenbank-Spektrum, 15(3), 175-184.

Authmann, C., Beilschmidt, C., Drönner, J., Mattig, M., Seeger, B. (2015): Rethinking Spatial Processing in Data-Intensive Science. BTW Workshops 2015: 161-170

Conference contributions

2017

Hess, B., Yihui. L., Dreber, N., Ludwig, M., Meyer, H., Meyer, K.M., Wiegand, K. (2017): A multifunctional, piosphere landscape generator (PioLaG) for grazing systems in southern African savannas. GfÖ/BES joint annual meeting: ecology across borders with BES, GFÖ, NECOV & EEF, Ghent, Belgium, 11.-14.12.2017.

Meyer, H., Authmann, C., Dreber, N., Hess, B., Kellner, K., Morgenthal, T., Nauss, T., Seeger, B., Tsvuura, Z., Wiegand, K. (2017): IDESSA: An Integrative Decision Support System for Sustainable Rangeland Management in Southern African Savannas. Geophysical Research Abstracts 19: EGU2017-8802

2016

Kellner, K., Harmse, C.J., Fouche, J.H., Pelser, J.J. (2016): Restoration of degraded arid and semi-arid savannas in South Africa. SER 2016 - Best practice in restoration, 10th European Conference on Ecological Restoration, Freising, Germany, 22.-26.08.2016.

Ludwig A, Meyer H, Higginbottom T, Nauss T (2016): Classifying Google Earth images as training sites for application to a larger scale monitoring of bush encroachment in South Africa. European Geosciences Union General Assembly, Vienna, Austria, 17.-22.04.2016.

Morgenthal, T., Meyer, H., Kellner, K., Nauss, T. (2016): A Sentinel based analysis of vegetation patterns of a semi-arid savanna in South Africa. GFÖ 2016 - 150 years of Ecology - lessons for the future, 46th annual meeting of the Ecological Society of Germany, Austria and Switzerland, Marburg, Germany, 05.-09.09.2016.

2015

Meyer, H., Kühnlein, M., Appelhans, T., Nauß, T. (2015): Comparison of machine learning algorithms for their applicability in satellite-based optical rainfall retrievals. Atmospheric research. Geophysical Research Abstracts 17: EGU2015-3321-1.

Authmann, C., Beilschmidt, C., Drönner, J., Mattig, M., Seeger, B. (2015): Explorative Workflows for Data‐Driven Geo‐Science GFÖ 2015 - Ecology for a sustainable future, 45th annual conference of the Ecological Society of Germany, Austria and Switzerland, Göttingen, Germany, 31.08.-04.09.2015.

Hess, B., Hanss, S., Wiegand, K., Kellner, K., Morgenthal, T., van Rooyen, A.F., Jordaan F. (2015): Predicting savanna dynamics in response to management and climate change: a modelling approach for decision support. GFÖ 2015 - Ecology for a sustainable future, 45th annual conference of the Ecological Society of Germany, Austria and Switzerland, Göttingen, Germany, 31.08.-04.09.2015.

Van Rooyen, S., Kellner, K., Dreber, N. (2015): Short-term structural responses of woody savanna vegetation to non-selective chemical bush control, South Africa. GFÖ 2015 - Ecology for a sustainable future, 45th annual conference of the Ecological Society of Germany, Austria and Switzerland, Göttingen, Germany, 31.08.-04.09.2015.

2014

Authmann, C., Beilschmidt, C., Drönner, J., Mattig, M., Seeger, B. (2014): Analytical Workflows for Large Data. TDWG 2014 Symposium: Biodiversity Informatics workflows and services.

Theses

In progress

Authmann, C. (in prep.): Efficient raster processing on modern hardware. PhD thesis, Philipps-University Marburg.

Esterhuizen, A. (in prep.): The effect of fire on savanna vegetation dynamics in the semi-arid Molopo Bushveld region of the North-West Province, South Africa. MSc thesis, North-West University.

Hess, B. (in prep.): Modelling, management and restoration of grassland savannas in southern Africa. PhD thesis, Georg-August-University Göttingen.

2018

Limberger, O. (in prep.): Simulation of the behavior of wildland fires in savanna ecosystems. MSc thesis, Georg-August-University Göttingen.

2017

Fouché, J. (2017): Landscape function in bush thickened and -controlled areas of the semi-arid savanna in the Molopo region, South Africa. MSc thesis, North-West University.

Meyer, H. (2017): Data-driven model development in environmental geography. Methodological advancements and scientific applications. PhD thesis, Philipps-University Marburg.

Pillay, T. (2017): Understanding the effects of changing climate and land use on woody plant encroachment in South African grasslands and savannas. PhD thesis, University of KwaZulu-Natal.

Schmidt, J. (2017): Monitoring hourly air temperature in South Africa using MSG SEVIRI and machine learning. BSc thesis, Philipps-University Marburg.

Van Rooyen, S.E. (2017): Composition and structure of woody vegetation in thickened and controlled bushveld savanna of the Molopo, South Africa. North-West University. MSc thesis, North-West University.

2016

Hesselbarth, M. (2016): Spatial patterning of key woody species in relation to bush density: A comparative assessment in semi-arid and mesic savannas, South Africa. MSc thesis, Georg-August-University Göttingen.

Reitz, O. (2016): Interpolation monatlicher Niederschläge in zwei südafrikanischen Regionen: Vergleich von Random Forest und Kriging. BSc thesis, Philipps-University Marburg.

Yihui, L. (2016): Modelling piosphere gradients across South African farms with Netlogo. BSc thesis, Georg-August-University Göttingen.

Körber, M. (2016): Caching von Geodaten. MSc thesis, Philipps-University Marburg.

2015

Dunkl, I. (2015): Integrating climate change in the MIDESSA South African savanna model. Project thesis, University of Kassel.

Ludwig, A. (2015): Identification of bush encroachment in South African Savannas: A machine learning based approach using Random Forests and MODIS imagery. BSc thesis, Philipps-University Marburg.

Mureva, A. (2015): Ecosystem carbon change of shrub-encroached grasslands across a precipitation gradient in South Africa. PhD thesis, University of KwaZulu-Natal.

Polakowski, F. (2015): Remote-sensing based predictions of bush encroachment in South Africa using Random Forests. BSc thesis, Philipps-University Marburg.

van Rooyen, S. (2015): Comparison of plant diversity of shrub thickened and chemically controlled savannas in the Molopo district, North-West Province, South Africa. BSc Honours thesis, North-West University.