Predicting plant biodiversity in changing Dutch landscapes

Informations

Funding country

Netherlands

Acronym

-

URL

-

Start date

1/1/2000

End date

8/31/2005

Budget

-

Fundings

Abstract

Plant biodiversity is declining fast in the Netherlands as well as in other European countries. The presumed causes for this decline are habitat deterioration and fragmentation. The loss of biodiversity affects ecosystem functioning and this might threaten the sustainability of human land use. This has raised great public concern and a number of measures have been put in place with the aim of restoring biodiversity. However, notwithstanding some local successes, our restoration efforts did not stop the general decline in plant biodiversity. This programme aims 1) to analyze whether common traits occur within the groups of 300 decreasing and 150 increasing species on the national level and 2) to develop the scientific insights for better prediction of the results of restoration efforts and thus contribute to a better investment of scarce nature conservation funds. This we hope to achieve by setting realistic targets for the restoration of plant biodiversity by better understanding the constraints that operate on (changes in) species composition in a range of plant communities on a national scale covering the Netherlands. Traditionally the emphasis in nature conservation has been on alleviating the effects of habitat deterioration, but it is now becoming increasingly clear that habitat fragmentation and associated problems for recolonisation after local extinction might play an equally important role. We therefore need to understand the relative importance of both sets of processes at the relevant scale of the landscape unit. For this we intend to exploit the unique database of over 300,000 spatially defined vegetation descriptions that are now available to us covering almost all habitat community types, using the most recent database management techniques to mine these data, and combine these data with the database of 9,000,000 records from 1902-1999 on flora inventories of every km2 in our country. Based on a hierarchic land unit classification, the available databases will allow a precise evaluation of the species pool of the given land units and the plant communities that are realized from this pool given their site condition and spatial position. The research will focus on the dry and wet parts of the Pleistocene sand area of the Netherlands; here, the inventories on vegetation and flora will be completed with data on seed bank composition and dispersal, part I y al ready available in a national database and part I y to be collected in the field. The spatial analysis will then be combined with a functional analysis, relating species frequencies over space and over time -both databases cover several decades -to three traits that define a plant species spatio-temporal mobility: dispersal capacity, seed dormancy and adult longevity. To this end an existing preliminary database for these traits will be expanded and updated. The combination of both approaches will allow an interpretation of local plant biodiversity not only from habitat characteristics but also from species availability and functional traits. These interpretations will then be validated against a number of ongoing nature restoration projects and the results of long-term changes in plant biodiversity in permanent plots in nature reserves. The general perspectives for this programme are: .more insight in the mechanisms behind the decline, increase and invasiveness of plant species in the Netherlands .a better understanding of the mechanisms that define local plant biodiversity within a defined land unit, based on both a spatial and a functional analysis .a more realistic set of targets for the restoration and maintenance of plant biodiversity and a more optimal allocation of nature conservation resources.