Manipulation of above- and belowground biodiversity as a tool in the restoration of ecosystem functioning

Informations

Funding country

Netherlands

Acronym

-

URL

-

Start date

2/7/2000

End date

5/1/2006

Budget

-

Fundings

Abstract

Biodiversity of natural ecosystems is strongly affected by ecosystem processes such as primary production, evapo-transpiration and soil nutrient turnover. But recent studies also show that different plant and animal species have major impacts upon ecosystem processes. Thus, changes in biodiversity can alter ecosystem processes, which may have important feedback effects on the species composition. There are still large gaps in our knowledge about these feedback effects, especially regarding the interactions between above- and below-ground biodiversity , and their consequences for restoration of natural ecosystem processes. In the Netherlands, an increasing area of agricultural pastures is becoming available for nature restoration. In various restoration experiments in pastures withdrawn from agriculture, plant species diversity still did not increase, even after 20 years. Apparently, there are important bottle-necks during the restoration process. Such bottle-necks can be due to inappropriate abiotic conditions, but may also be caused by the low dispersal abilities of many plant and animal species that are not able to reach the target area. Especially, many soil organisms have extremely limited dispersal capacities. Effects of plant seed introduction have been extensively studied, but almost no attention has been paid to effects of the introduction of soil organisms or small above-ground herbivores on plant species diversity in the field. We propose to investigate if the introduction of above- and below-ground species or functional groups of species, and thus increasing the diversity , in former agricultural pastures is an important additional measure for restoring ecosystem processes. We will carry out field and garden experiments in which we will introduce vascular plant species, small and large above-ground grazers, below-ground grazers (root-feeding nematodes and microarthropods), arbuscular mycorrhizal fungi, fungal grazers and decomposers to low diversity ecosystems. We will test the hypotheses that the introduction of these different groups of organisms will facilitate the increase in plant species diversity and that the increase in plant diversity will positively affect the diversity of the various groups of soil organisms. Subsequently, we will test whether the introduction of these organisms may help to overcome the bottle-necks that are faced durin the restoration of biodiversity in pastures withdrawn from agricultural production.