Biogeography and shape of fungal fairy rings in the Apennine mountains, Italy

Abstract

Aim: Fungal 'fairy rings' (FRs) are regular bands of vegetation caused by a centrifugal expansion of fungal mycelia. It is well established that FR fungi affect both soil chemistry and microbiome, but nothing is known about the distribution of these patterns at the regional scale. Here, we assess the abundance and occurrences of different FR shapes i.e. rings, arcs and rotors, and explore their association with geomorphology and climate. Location:The Apennine Mountains, 300-km latitudinal gradient along the Italian Peninsula.Taxon: Basidiomycetous fungi.Methods: High-resolution freely available images were gathered to study FR shapes and distribution in the Apennine region of Italy. First, 12 mountains with different elevations and geomorphology were studied to assess the colonial density and relative distribution of FR type. FR distribution and shape and size of additional 616 FRs were studied in 61 study sites and relationship with selected climatic and topographic variables were assessed using different modelling approaches.Results: Overall, 1163 FR structures were found across the study area. Arcs were the most common shape followed by rings. Rotors were rare, accounting for less than 2% of all observations. Fungal colony density varied largely both among and within sites, averaging 6.7 arcs, 2.2 rings and only 0.1 rotors per ha. On average, arcs (18.8 m) were similar in size compared to rotors (18.4 m) whilst rings were smaller (11.7 m). Arcs presented a higher frequency of occurrence on steeper slopes whilst rings were mostly found on flat and moderate slopes. FRs occurred within the altitudinal range between 546 m and 2148 m a.s.l., corresponding to temperatures between 3.4 and 12.7°C and rainfall between 1100 and 1300 mm per year.Main Conclusions: FRs are common elements of the Apennine grassland landscape where they may contribute to the maintenance of plant and microbial diversity. Better systematic identification of the fungal species involved in the formation of FRs is required. Further research that combines long-term field manipulative experiments and

Checklist of Macrofungi Associated with Nine Different Habitats of Taburno-Camposauro Massif in Campania, Southern Italy

“…The data presented here can inform future directions in conservation policies for different management authorities. As macrofungi may serve as bioindicator species [7,31,32], the understanding of their presence and distribution became an essential factor to monitor the ecological state of natural environments. Future censuses of macrofungi in time series can provide valuable insights into the changes of biotic populations and communities in climate-change conditions, and can help to assess the overall health of ecosystems [10,33].…”

“…All these taxa have developed adaptations to the grassland environment, decomposing soil humus, hemicellulose/cellulose-based litter residuals, or exploiting dung released by grazing herbivores. Notably, the conservation state of grassland is also assessable by the presence of fairy rings (circular colonies of expanding mycelium marked by changing vegetation or sporophores) that occur in regular circular patterns only in low-perturbed conditions [31,51]. The presence of several species belonging to the Agaricus genus, as well as Marasmius oreades and Calocybe gambosa, was observed [13,51]; that, however, does not form a complete circular pattern but a fragmented one, indicating a perturbed state in grassland habitats.…”

Analysis and numerical simulations of travelling waves due to plant–soil negative feedback

“…These types of patterns were observed as early as 1950 [23] under different slope conditions [38] and have been studied in numerous works including [11,12,15]. As reported by recent experimental work, this type of pattern appears also in other biological systems, such as fungi [1]. Partial differential equations (PDE) have been widely used with the aim to reproduce experimental observations by linking the occurrence of such patterns to space-dependent factors [2,3,15,34,38].…”