Plant species and availability of nutrients

In the last 20 years, eutrophication has led to a decline in plant species typical of infertile habitats and an increase in species of fertile habitats.

Trends

Between 1980 and 2000, plant species of infertile habitats declined, while species of fertile habitats (nitrophytes) greatly increased. This is an indication of the effects of eutrophication. Most of the plant species of infertile habitats are uncommon and are endangered in the Netherlands; most of the species of fertile habitats are common. So, the rare species are getting rarer and the common species are getting commoner.

Technical note

The data are from FLORON's Florbase database which contains data on the presence of higher plants in 1 km² grid squares. For analysis, the data were grouped in two periods: 1975-1985 and 1986-2000, indicated in the figure as 1980 and 2000, respectively. For each period, the number of grid squares in which a certain species had been recorded was determined. The figures for the two periods were compared, and the resulting difference was then related to various environmental factors, such as fertility preference. This preference was expressed as an Ellenberg value. The Ellenberg scale runs from nitrogen-avoiding to nitrophilous: classes 1, 2 and 3 contain species that shun nitrogen, classes 4,5, and 6 contain the species that are moderately nitrophilous and classes 7, 8 and 9 contain the nitrophytes.

References

• Tamis, W.L.M., M. van 't Zelfde en R. van der Meijden (2001). Changes in vascular plant biodiversity in the Netherlands in the 20th century explained by climatic and other environmental characteristics. In: H.van Oene et al. Long-term effects of climate change on biodiversity and ecosystem processes. Dutch National Research Programme on Global Air Pollution and Climate Change.