Jan Nyssen

Nyssen’s research showed that high levels of soil loss in the Ethiopian highlands are caused by a combination of erosive rainfall, steep slopes (as a consequence of rapid tectonic uplift during Pliocene and Pleistocene), and impacts of deforestation, overgrazing, an agricultural system where the open-field system dominates, and the aftermath of povery induced by the feudalism. He further studied in the Ethiopian highlands how the high density of soil and water conservation structures led to land resilience. Through the use of rephotography, Prof. Nyssen could link up changes in Ethiopian landscapes with land degradation.

Nyssen’s research in Belgium is also related to the consequences of human activities on geomorphic processes: the reintroduction of beavers, spoil tips of the derelict coal mining industry, and the age-old agriculture in the Pays de Herve (the region where he was born), which led to the occurrence of lynchets or cultivation terraces, by analogy to a common practice in current Ethiopia; The beaver dams have drawn his attention because they contribute to conserving water in the rivers’ headwaters. He studied their effect on discharges of the Chevral creek, that is part of the Ourthe basin. The research confirmed that such dams have a buffering effect on discharges: downstream the peak discharges are much lower that what was observed before beaver reintroduction.

Nyssen’s interest in Geography "was mainly motivated by the willingness to contribute to solving issues of unequal development worldwide”. His current research is related to land degradation and land rehabilitation. For instance, in Ethiopia he monitored how large tracts of land could be restored thanks to the conservation activities of millions of farmers. With colleagues, he also supports reforestation projects, leading to a yearly 10,000 tonnes of additional carbon storage.

Links with climate change and the situation in his home country are common; Nyssen stressed in 2019 in a video message in the framework of the “We Change for Life” campaign, that the inhabitants of 9 small villages in their projects in Ethiopia could annually sequester about half the carbon volume as compared to what the whole Flemish region in Belgium could reach as reduction of carbon emissions (that was a meagre 2.5% of the objectives).

Finally, one gets the feeling that ‘Big Oil’ lobby is so strong, can we have an impact at all? (…) Society should switch from fossil-fuel based growth to socially-adapted green shrinking, which is possible if the economy does not need to sustain corporate greed.

His research contributes to the identification and quantification of changes in the coupled system “humans-environment” – with focus on slope processes, hydrogeomorphology, land degradation and soil conservation. Most of his research activities are in Ethiopia.

Nyssen also contributed to many other publications as co-author – see UGent’s academic bibliography

Through the years, he lived the many changes that occurred; since his first stay in 1994, he observed that the amount of food available to rural households, as well as the overall living standard has strongly improved.

Nyssen was employed as a mailman (1977-1997) in Liège (Belgium). Starting 1991, he did a parallel study of Geography at the University of Liège; he obtained the degree of Licentiate in Geography in 1995, with a dissertation on soil erosion in Ethiopia. Between 1998 and 2001 he carried out PhD research at KU Leuven University (Belgium), in which he investigated the role of human and natural processes in land degradation in the Ethiopian highlands. Promoters of this research were professors Jean Poesen, Seppe Deckers (both at KU Leuven), Jan Moeyersons (Royal Museum for Central Africa in Tervuren) and Mitiku Haile (Mekelle University in Ethiopia). He worked also several years in projects of university development cooperation in Ethiopia. Since 2007 he is professor at the Department of Geography of Ghent University; in 2014 he was appointed as Full Professor.

Jan Nyssen (born Sint-Martens-Voeren, 1957) is a Belgian physical geographer, and professor of geography at Ghent University.