Beschreibung

Alpine pastures are semi-natural high nature value grassland ecosystems. They formed since the onset of pastoralism and underwent major changes in the management regime that, in turn, impacted the ecosystems changing the structure, diversity and functionality of the vegetation as well as the ecology of the soil, including its chemical-physical properties and its biodiversity. As a result, we face changes in nutrient networks and question the sustainability of ecosystems and their functions for animal husbandry. In this context, biological parameters can serve as early warning signals (EWS) to identify the location and extent of the area of impact. For example, species such as the grass Nardus stricta L. act as indicators for changes in soil acidity that ultimately affects cation exchange, species composition, and the quality of the forage itself. One of the most interesting and topical questions is the limits to operate within crossing an ecosystem tipping point. A tipping point is reached when slowly changing environmental conditions spark a sudden shift to a new and sometimes very different or even irreversible state. EWS of tipping points are therefore vital to anticipate system shifts. In this project, we aim to study reference areas of mountain pasture ecosystems to make a spatially explicit quantification of the impact of different grazing management (homogeneous rotation grazing, heterogeneous free-range grazing, abandonment) at different spatial, biological, and ecological scales. To do so, within a management type, vegetation plots will be distributed randomly. Within plots, indicator species of vegetation succession after grazing reduction will be identified. At the individual to plot scale, we aim to study interactions between soil and plant biodiversity. This will be done by linking vegetation plot data and metacommunity data of soil bacteria, fungi, protozoa, micro- and mesofauna, with physico-chemical soil properties. At the site scale, we will link the plant diversity pattern to the grazing behavior of animals (sheep, cattle) by recording their movement patterns with GPS-sensors to be able to track their feeding behavior on the one hand and to determine the energy consumption due to locomotion on alpine pastures on the other hand. Based on the results, we aim to identify threshold values for biological and ecological parameters indicating tipping points of biodiversity for mountain pastures. Moreover, our findings can show how tipping points are linked to animal performance and productivity of the animal production system. The project will thus positively contribute to the sustainability strategy of protecting semi-natural high nature value grasslands and their biodiversity. Finally, we will also organize workshops and meetings to share knowledge with stakeholders and local farmers to support the implementation of the sustainability strategy in practice.

Partner

Lead Partner Freie Universität Bozen, Partner Universität Innsbruck