Disputation för filosofie doktorsexamen i geografi med kulturgeografisk inriktning vid Samhällsvetenskapliga fakulteten, Stockholms universitet, där Oscar Jacobsson framlägger sin avhandling ”När floden märkte marken: Om bruket av översvämningsmark längs med Emån och Ätran 1500–1910”.

Plats: De Geersalen, Geovetenskapens hus, Svante Arrhenius väg 14, Frescati, Stockholm.
Tid: Kl. 13.00 den 10 februari 2023.

Opponent: Docent Jesper Larsson, Institutionen för stad och land; Avdelningen för agrarhistoria, Institutionen för stad och land, Sveriges lantbruksuniversitet.

Huvudhandledare: Professor Anders Wästfelt, Kulturgeografiska institutionen, Stockholms universitet. Handledare: Universitetslektor Johan Berg, Kulturgeografiska institutionen, Stockholms universitet.

Ordförande vid disputationen: Professor Bo Malmberg, Kulturgeografiska institutionen, Stockholms universitet.

Betygsnämndens ledamöter: Docent Maja Lagerqvist, Kulturgeografiska institutionen, Uppsala Universitet, docent Göran Ulväng, Ekonomisk-historiska institutionen, Uppsala universitet, och professor Fredrik Charpentier Ljungqvist, Historiska institutionen, Stockholms universitet. Suppleant: Docent Lowe Börjeson, Kulturgeografiska institutionen, Stockholms universitet.

Abstract: 

Large landscape transformations were an integral part of the agricultural revolution in Sweden, starting during the late 18th century. The 19th century was an especially intensive century when it comes to the transformation of the cultural landscape, not the least marked by extensive changes in the use of agricultural wetlands with interventions in watercourses, lowering of lakes and wetland reclamation. Many wetlands that had previously been used for meadows were now turned into arable fields.

In this thesis, these changes are studied through a long-term perspective on floodplain land use along the rivers Emån and Ätran during the period 1500-1910 as part of a wider economy and reflecting the transformation of human-environmental relations. The studied period permits an analysis of the whole transformation process from floodplain meadows to arable fields, as well as covering some of the ensuing complexities of floodplain drainage during the 19th century. In the thesis, the relation between the floodplain and the agricultural economy is studied as well as the connections to the development of flood-related problems. Differences in 19th century floodplain reclamation by Emån and Ätran are analysed in detail. Lastly, the thesis discusses how the different conditions of the floodplain was handled over time and what this can tell us about human-environment relations from short- and long-term perspectives. Theoretical perspectives ranging from the ‘water system’ perspective, landesque capital, geographic constraint to processual landscapes are mobilized to further deepen this analysis. The empirical material consists of historical maps and a wider range of written sources combined with physical geographical data.

The thesis concludes that flood-meadows played a more significant role in the agrarian economy by the river Emån during the early modern period, where flooding contributed to increased hay harvests. By the river Ätran, flood-meadows were extensive but did not differ significantly in yields from other types of meadows. The transformation from flood-meadows to arable fields were tied to intensified animal husbandry during the 19th century, with the need for other types of fodder and increasing water control and flood management. This was to a large part driven by processes related to agricultural globalization. By the river Emån, arable fields had already previously been located on raised parts of the floodplain, but transformations of grain production during the 18th century caused more substantial problems which also played into early 19th century reclamations. The local inhabitants did not reflect upon the effects of land use changes on the pattern of flooding problems, showing instead more interest in more direct changes to the water system such as mill dams, and natural obstructions in the river channel. Differences in the use of the floodplain by Emån and Ätran are also raised in the thesis, showing how humans in different contexts interact with variations of physical geography. A fundamental conclusion is that humans to a large extent tend to use natural resources for short-term gains within given economic contexts and have larger problems formulating solutions to long-term problems or foreseeing the long-term effects of current practices.

Nyckelord: historical geography, agricultural history, water history, floodplain, Sweden, wetland reclamation, meadows, Emån, Ätran, agricultural transformation, human-environment relations.