Most terrestrial plant, fungi and animal species need forests, where an extremely complex network of biotic interactions occurs.
Overstorey stand structure has a key role in driving biodiversity patterns, also through tree related microhabitats and deadwood. Understorey vegetation can modify local environmental conditions affecting tree seedling establishment and predation by herbivores. Small mammals with scatter-hoarding habits act as seed predators and dispersers, thus influencing tree species regeneration, and in turn forest productive and ecological functions.
Coppice systems exploit the ability of deciduous tree species of generating new stems from the cut stump. While in Europe only about 5% of forests regenerate as coppice, in Italy coppice is applied on about 50% of forests.
As a coppiced forest overstorey regenerates, diverse environmental factors shift: understorey composition varies mediated by plant functional traits, and in turn understorey interactions with other ecosystem components change.
Several studies focused on these individual mechanisms, however the effect of management practices on forest biodiversity is given by the interplay among several different ecosystem components. This project has the goal of understanding the mechanistic relationships between forest management, overstorey stand structure, understorey functional traits, and small mammal populations in deciduous oak coppice forests.
Our specific aims are to quantify the effects of coppice regeneration on small mammal species abundance. We will focus on the role of on food resources and habitat quality, understorey functional traits, deadwood and tree microhabitats.
The study will be performed in Tuscany (Italy) across 12 coppiced stands dominated by Turkey oak that encompass different regeneration phases. The sampling will focus on overstorey structure, understorey species and functional diversity and small mammal species abundance.
Forest cover over one third of European land. Although 24% of European forests are protected for biodiversity conservation, only 2% are undisturbed by man (Forest Europe, 2020). On the bright side, two thirds of European forests regenerate naturally vs. about 30% that are regenerated through planting or seeding, while only about 5% regenerate as coppice. Coppice systems are based on the ability of deciduous tree species of generating new stems from the cut stump.
These European figures are similar for Italy, where forests cover about one third of Italian land (RAF, 2018), and have been altered in their structure and composition by a long history of exploitation for timber and non-timber products. Italian forests mostly regenerate naturally after being harvested for timber (Corona et al., 2019), however, in Italy, coppice is one of the most widespread silvicultural system, which is applied on about half of Italian forests (RAF, 2018), far more than in other regions in Europe where coppice is common, i.e., 16% of forests regenerate as coppices in eastern southern Europe (Forest Europe, 2020).
Coppices are unique forest ecosystems, whose structural and compositional features are relatively rare in Europe and globally, and their understanding is particularly important, especially in Italy. The recent increase of invasive species worldwide currently represents a threat to these ecosystems (Seebens et al., 2018) that have a key role for restoration of biodiversity and ecosystem services and for improving rural landscape sustainability is being increasingly valued (Benayas et al., 2012).
In Italy, coppiced forests dominated by deciduous oaks typically occur in hilly areas with submediterranean climate. The most common dominant species are Turkey oak and white oak, which have a prominent role in terms of land cover, biodiversity conservation and firewood production (Bernetti & la Marca, 2010). Most Turkey oak (82%) and white oak (76%) coppiced forests are coppices with standards, i.e., a share of trees is not harvested since they will provide seeds for regeneration, shelter to seedlings, and limit soil erosion. Harvesting rotation periods range between 18-25 years in fertile sites, and between 25-35 years in those with poor soils, steep slopes to obtain wood of larger sizes (Quatrini et al., 2017).
The economical-social change and the spread of fossil fuels caused a heavy reduction in the use of coppice firewood and charcoal since 1950¿s. Since then, homogeneous forest landscapes dominated by intensively managed coppices, shifted to forest with diverse structural features, growing stocks and growth dynamics, which, however, shared a common origin. Currently, a large share of the area labelled as coppices is represented by stands under lengthened rotations, outgrown coppices, and coppices in conversion to high forest (Fabbio and Cutini 2017). High forests ensure a greater ecological continuity and favor species needing closed forests conditions, but the progressive reduction of coppices is causing a decrease in the ecological conditions and the species related to coppices (Buckley, 2020).
For these reasons it is particularly important to assess the full range of ecosystem properties and conservation values related to coppice forests, in order to inform broad scale forest planning about the role of coppices in maintaining forest biodiversity at the stand and at the landscape level.
The present project will pursue this aim by assessing a wide range of direct and indirect mechanisms that derive from the ageing of coppice forests, from understorey species and functional diversity to small mammal abundance patterns.
References
Benayas, J. M. R., & Bullock, J. M. (2012). Restoration of biodiversity and ecosystem services on agricultural land. Ecosystems, 15(6), 883-899.
Bernetti G., La Marca O. 2010. Il bosco ceduo nella realtà italiana. Atti dei Georgofili.
Buckley, P., 2020. Coppice restoration and conservation: a European perspective, Journal of Forest Research 25: 125-133.
Corona P., et al. 2019. Pianificazione ecologica dei sistemi forestali. Compagnia delle Foreste, Arezzo, pp. 198.
Fabbio, G. and Cutini, A. 2017. Coppice today: which management beyond definitions? - Forest@ 14: 56¿73.
FOREST EUROPE, 2020: State of Europe¿s Forests 2020
Quatrini V., et al. 2017. Caratteristiche produttive e gestione dei cedui in Italia. L¿Italia Forestale e Montana 72: 273-313.
RAF 2018. Rapporto sullo stato delle Foreste e del settore forestale in Italia. Prodotto dalla Rete Rurale Nazionale (RRN 2014-2020). Compagnia delle Foreste (Arezzo).
Seebens H., et al. 2018. Global rise in emerging alien species results from accessibility of new source pools. ¿ Proceedings of the National Academy of Sciences of the United States of America 115: E2264¿E2273