The study performed by UNIMONT and the Department of Agricultural and Environmental Sciences – Production, Territory, Agroenergy of the University of Milan, within the PNRR Agritech Project, aims to develop innovative tools and practices for the adaptive management of pastures in the alpine valleys of Val Camonica (Lombardy Italy). It is based on the characterisation of soil quality, assessed from humus type and soil type (first step) and biological quality based on the presence and biodiversity of micro-arthropods.
In the Italian Alps the last decades have witnessed a significant trend towards the abandonment and degradation of mountain pastures and meadows, which has altered valuable ecosystem services and compromised the circularity of agricultural and livestock production at farm and regional level. To meet this challenge for mountain territories, UNIMONT (BS, Italy) and the Department of Agricultural and Environmental Sciences – Production, Territory, Agroenergy of the University of Milan are developing a series of studies on Alpine meadows and pastures. The research, conducted within the PNRR Agritech projects, aims to develop innovative multi-scale digital farming tools and practices for adaptive pasture management. Val Camonica (Lombardy Italy), the Mortirolo area in particular, has been chosen as a case study and prospective ‘living lab’ for a better spatial management of Alpine meadows and pastures.
The survey carried out during summer 2024 involved the collection of 30 samples, for the characterisation of the soil quality on the basis of pedofauna, for the determination of the QBS-ar (Soil Biological Quality) index. This index is based on the presence and diversity of micro-arthropod communities. It was considered important to include the study of edaphic fauna as it plays a key role in soil formation and functioning, through processes of decomposition of organic matter and its mineralisation, which are fundamental to the functionality of the soil ecosystem and the release of nutrients, thus impacting their fertility. In addition, complex biological communities in the soil system make it more resilient to the negative effects caused by climate change, such as drought events or extreme rainfall, and make the soil less vulnerable to erosive processes.
The working tools are a shovel, pickaxe and lastic bags. Small undisturbed soil samples of 10 x 10 cm and 10 cm depth are taken in each sample, across a land use gradient (from used pasture to abdandoned grassland transformed into shrubland/forest). The organic surface of the topsoil is removed with shears. The samples are then placed in bags with a little air to keep the soil alive until the typological and quantitative analysis, which will be carried out within a maximum of 48 hours. The samples, stored in the dark at room temperature, are brought to the laboratory as soon as possible to proceed with the extraction of the pedofauna using the Berlese-Tullgren Selector. The results obtained will be used to determine the Soil Biological Quality Index (QBS-ar, Parisi 2001), an approach that combines methodological simplicity with the possibility of obtaining feedback on different situations of soil biological quality.
The method involves the microscopic recognition of biological forms with different degrees of adaptation to edaphic life (e.g. reduction and loss of eyes or depigmentation) and is based on the principle that the greater the adaptation, the better the biological quality of the soil, since conditions of chemical and physical stress, due to both anthropic and natural causes, lead to the depletion of the most adapted organisms, which, being more vulnerable and less able to cope with unfavourable conditions, are the first to disappear.
Each Biological Form of the mesofauna present in the sample is assigned an Ecomorphological Index value (EMI), which increases with the degree of adaptation to edaphic life; Euedaphic Forms (EF) are defined as those arthropods with a high degree of adaptation to soil dwelling, with a maximum EMI score (equal to 20). On the contrary, ubiquitous arthropodes such as mites are the least adapted, and they are assigned the lowest EMI score (equal to 1).
Since the sampling for mesofauna was carried out at the sites where the soil-humological-vegetation study was performed (during the 2023 survey), the data on plant communities and the different degree of pasture abandonment will be correlated with QBS data based on mesofauna with different degrees of adaptation to soil life. The aim of this study is therefore to investigate the state of soils to assess the quality of high-elevation pastures in relation to their management. The recovery of the most suitable agronomic practices favouring soils with high QBS could provide indications on which actions to include in pasture management plans.
For more information: michele.damico@unimi.it, francesca.sapio@unimi.it, silvia.chersich@unimi.it
