In Europe’s rural landscape, the sight of abandoned agricultural fields is increasingly common. In some cases, the abandonment of less fertile or less accessible cultivation sites is caused by mechanisation and intensification of agriculture. In others, it is rural population exodus that leads to a decline in land management. Such transformations of the agricultural environment create a unique opportunity to study vegetation succession: the process through which the species and habitats in formerly cultivated fields change over time.
Studying vegetation succession is relevant for both environmental conservation and ecological restoration initiatives, as it provides researchers with important information such as species richness, the rate of succession, and what kinds of habitat tend to become established through natural processes. But research in the field does not come without challenges. One of them is how to observe long-term vegetation changes in a consistent and comparable manner. Another is how to cover a wide range of environmental conditions.
To better understand the strengths and weaknesses of different observation methods, WILDCARD researchers from the University of South Bohemia conducted a study gathering data from abandoned fields of the Bohemian Karst Protected Landscape Area, in the Czech Republic, since 1975. The research paper, recently published in the Journal of Vegetation Science, represents the first study of vegetation change in old fields spanning multiple decades that combines two frequently used survey methods. It compares fields in various successional stages at the same point in time (chronosequence), which results in faster acquisition of results but has limits in predicting restoration processes in disturbed sites, and the use of semi-permanent plots, which requires greater effort as researchers resurvey comparable areas at different points in time.
Our researchers found that a chronosequence approach can reliably reveal general successional patterns comparable to those obtained from semi-permanent plots. The combined method showed that both approaches studied in detail show similar succession patterns, regardless of the sampling methods used. However, to avoid pitfalls in measurement and sampling methods, the authors suggest combining different approaches to generate more reliable results. Their analysis of vegetation succession has also shown that, in fields with a moderate supply of moisture (mesic areas) a woodland landscape with the presence of trees and shrubs emerged within 25-30 years. Dry fields, conversely, continued to be dominated by perennial grasses, accompanied by scattered trees and shrubs.
Řehounková K., Tichý L. & Prach K. 2024. Succession in abandoned fields: Chronosequence data verified by monitoring of semi-permanent plots. Journal of Vegetation Science 35: e13303. http://dx.doi.org/10.1111/jvs.13303