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Ulrich Mahler’s Exkursionszettel Wagbachniederung

Submitted by

Johanna Just

Ulrich Mahler, Exkursionszettel Wagbachniederung, Oberhausen-Rheinhausen, 25.-29.05.2022, Back

Ulrich Mahler, Exkursionszettel Wagbachniederung, Oberhausen-Rheinhausen, 25.-29.05.2022, Front

Ulrich Mahler’s Exkursionszettel exemplifies the importance of embodied tacit knowledge in the management of constructed landscapes.

Mahler is an expert on the nature reserve and birding hot-spot NSG Wagbachniederung. Although he retired from the nature protection agency, where he was responsible for the area for more than 50 years, he remains the site’s guardian. The artificial wetland, once created through wastewater spillage from a nearby factory, is increasingly threatened by heat and water scarcity. Today it relies on an irrigation system that connects the site to a nearby flooded gravel pit. Mahler is the only experienced person to operate it: he knows when and for how long to switch on the pump to maintain the right water level.

Spending several hours daily on site, Mahler keeps records of his excursions – the hours of irrigation and encountered birds – in the form of annotated maps that express the impossibility of codifying the complex management of the place.

Submitted by
Johanna Just is an architect and doctoral fellow at the LUS Institute at ETH Zürich. In her work, she traces relationships among more-than-humans and the environment in the Upper Rhine Plain and explores new modes of spatial representation. Currently, she is one of the guest editors of the 2024 issue of gta papers.


This object is part of the TACK Exhibition “Unausgesprochenes Wissen / Unspoken Knowledge / Le (savoir) non-dit”, in the section “Embodiment and Experience”.