Project

Back to overview

Restoration of semi-natural grasslands using topsoil removal: what are the consequences for the soil community diversity and soil processes through altered above-belowground interactions?

English title Restoration of semi-natural grasslands using topsoil removal: what are the consequences for the soil community diversity and soil processes through altered above-belowground interactions?
Applicant Schütz Martin
Number 166654
Funding scheme Project funding (Div. I-III)
Research institution Swiss Federal Research Inst. WSL Direktion
Institution of higher education Swiss Federal Institute for Forest, Snow and Landscape Research - WSL
Main discipline Botany
Start/End 01.11.2016 - 31.10.2020
Approved amount 236'699.00
Show all

All Disciplines (5)

Discipline
Botany
Ecology
Pedology
Agricultural and Forestry Sciences
Zoology

Keywords (12)

bacteria; earthworms; nematodes; soil respiration; nitrogen mineralization; soil diversity; Restoration; soil processes; fungi; archaea; micro-arthropods; above-belowground interactions

Lay Summary (German)

Lead
Der Schwund der Artenvielfalt geht weltweit unvermindert weiter und gilt als eines der grössten globalen Probleme. Ursachen für diesen Schwund sind überall dieselben: Landnutzungsänderungen sowie Intensivierung (Dünger) der landwirtschaftlichen Produktion. In der Schweiz sind in gewissen Regionen beispielsweise bis zu 99% der artenreichen Ökosysteme seit Ende des 19. Jahrhunderts wegen Landnutzungsänderungen verschwunden. Der Schutz der wenigen noch erhaltenen Reste reicht nicht, um den Artenschwund zu stoppen; sie müssten erweitert werden können.
Lay summary

Der Abtrag des mit Nährstoffen angereicherten Oberbodens ist eine gut untersuchte und erfolgreiche Methode, um degradierte Ökosysteme zu renaturieren. Oberbodenabtrag führt allerdings unweigerlich zu Disputen zwischen Natur- und Bodenschutzämtern, weil die Bodenfauna und Bodenprozesse potentiell negativ beeinflusst werden könnten. Untersuchungen über solche Auswirkungen des Oberbodenabtrags auf den Boden fehlen jedoch weitgehend.

Ziel dieses Forschungsprojektes ist, diese Wissenslücke zu schliessen. Wir werden Daten in mit Bodenabtrag renaturierten Gebieten erheben und diese mit Daten vergleichen, die in noch erhaltenen, artenreichen Resten sowie im weiterhin intensiv genutzten Landwirtschaftsland erhoben werden. Neben der Vegetation werden wir bodenchemische und –physikalische Parameter erheben, die Zusammensetzung und Populationsgrössen von wichtigen Organismengruppen im Boden (Pilze, Fadenwürmer, Milben etc.) erfassen sowie biogeochemische Bodenprozesse (Stickstoffmineralisation) untersuchen.

Diese Arbeit wird neue Erkenntnisse über Interaktionen zwischen ober- und unterirdischen Lebensgemeinschaften und deren Auswirkungen auf Ökosystemprozesse generieren und zeigen, welche Bedeutung der Artenvielfalt dabei zukommt. Zudem wird sie offene Fragen aus der Natur- und Bodenschutzpraxis im Zusammenhang mit Bodenabtrag zur Renaturierung artenreicher Ökosysteme klären. Der Praxisbezug ist unmittelbar gegeben, weil Ämter im Projekt eingebunden sind.


Direct link to Lay Summary Last update: 20.09.2016

Responsible applicant and co-applicants

Employees

Name Institute

Abstract

The loss of biodiversity is recognized as a worldwide threat. One of the main reasons for this loss is the destruction, degradation and fragmentation of species-rich (i.e., richness in aboveground plant species) habitats due to urban development or agricultural land use change. In Western Europe, these species-rich habitats comprise mainly semi-natural grasslands and heathlands. Even though conservation efforts were strengthened some decades ago, biodiversity loss was not halted; a trend-reversal is not in sight. Evidence is growing that it is not sufficient to protect the remnants of species-rich habitats, but that their restoration is necessary to enlarge and re-connect the small-scale remnants to larger networks.Scientific field experiments conducted in various countries in Western Europe showed that semi-natural grasslands and heathlands can be successfully restored, but that it is not enough to simply cease fertilization in agricultural land and “re-launch“ traditional management methods (cutting and of course removal of the biomass). A successful (short-term) restoration seemed only possible when the existing vegetation including roots and the topsoil layers were removed (topsoil removal). If seeds or hay from the species-rich target vegetation were added (topsoil removal + seeding), the success was even greater.In Switzerland, 99% of species-rich semi-natural grasslands were lost in many regions since the late 19th century. However, an implementation of topsoil removal methods have provoked a dispute between nature conservation and soil protection agencies due to a potential negative impact of removing the topsoil layers on soil community diversity and soil processes. This dispute is ongoing, mainly due to a lack of field studies and scientific data. The aim of the proposed study is to fill this gap in knowledge by assessing the effects of topsoil removal on soil diversity and soil processes in a two-way approach. First, we plan on using a large-scale restoration experiment that has been established over 20 years ago in Eigental valley (canton of Zürich, city of Kloten). The development of the vegetation was since monitored in plots where different restoration treatments were applied: cutting, topsoil removal and topsoil removal + seeding, but no other parameters were measured. We will assess how functional groups in soils (procaryotes, fungi, nematodes, arthropods, and earthworms) and soil processes (soil respiration, nitrogen mineralization) responded to the treatments over long-time frames and compare the results to soils found in the initial vegetation (agricultural plant communities) and remnants of the target vegetation (species-rich grasslands). In a second approach, we plan to determine the succession of belowground communities by comparing their development between sites of different restoration age (1 to 30 years; space-for-time approach). The proposed project is paramount to gain missing scientific knowledge with regard to interactions between the vegetation, soil communities and soil processes in restoration schemes and during succession in general. In addition, the findings of the study will immediately fed into practice since official agencies are associated with the project from kick-off.
-