The checklist serves as an informative method for evaluating the diversity, geography, and ecology of established and reproducing macrofungi. Additionally, considering macrofungi as bioindicator ...species, their census should be incorporated into efforts to monitor the state of health of ecosystems and directly applied to conservation policies. Between 2019 and 2023, a census of macrofungal species was conducted in Taburno-Camposauro Regional Park (Campania, Italy) across nine distinct habitats. A total of 453 fungal taxa were identified, including several new records for the Campania region. The fungal diversity exhibited significant variations based on the dominant plant species in each habitat. Fagacean tree species and
spp. shared similar fungal communities. Equally, coniferous tree species displayed a comparable fungal composition. In
and mixed broad-leaved forests, low levels of ectomycorrhizal taxa were observed alongside a concurrent increase in saprotrophs, indicating a disturbed habitat and a reduction in the Gadgil effect. Notably, lower fungal diversity was documented in the grassland habitat, suggesting the potential implications of wildlife imbalance and excessive grazing. The provided checklist constitutes a valuable resource for local management authorities, providing insights to formulate specific management policies.
Aims
Data on the decomposition of fine roots are scarce for the Mediterranean basin. This work aims to compare chemical traits, decomposition rate, and temperature sensitivity (
Q
10) for root and ...leaf litter of 43 Mediterranean species.
Methods
We carried out a two-years litterbag decomposition experiment using 43 fine roots litter and leaf litter types incubated in laboratory conditions at three different temperatures, i.e. 4 °C, 14 °C, and 24 °C. Litter was characterized for carbon (C), nitrogen (N), lignin and cellulose concentration, C/N, and lignin/N ratios.
Results
Fine root litter had lower N content but higher lignin concentration, lignin/N, and C/N ratios compared to leaf litter. The decay rate of fine root litter was slower than leaf litter. For both tissues, the decay rate was negatively associated with lignin concentration, lignin/N, and C/N ratios but positively with N concentration.
Q
10 was higher for fine root than leaf litter, with a positive correlation with lignin while negative with N concentration.
Conclusions
Our findings demonstrate a higher
Q
10 accompanied by a slower decomposition rate of fine root litter compared to leaf litter in Mediterranean ecosystems. These results must be considered in modeling organic C at the ecosystem scale.
Understanding processes controlling forest dynamics has become particularly important in the context of ongoing climate change, which is altering the ecological fitness and resilience of species ...worldwide. However, whether forest communities would be threatened by projected macroclimate change or unaffected due to the controlling effect of local site conditions is still a matter for debate. After all, forest canopy buffer climate extremes and promote microclimatic conditions, which matters for functional plant response, and act as refugia for understory species in a changing climate. Yet precisely how microclimatic conditions change in response to climate warming will depend on the extent to which vegetation structure and local topography shape air and soil temperature. In this study, we posited that forest microclimatic buffering is sensitive to local topographic conditions and canopy cover, and using meteorological stations equipped with data-loggers we measured this effect during 1 year across a climate gradient (considering aspect as a surrogate of local topography) in a Mediterranean beech treeline growing in contrasting aspects in southern Italy. During the growing season, the below-canopy near-ground temperatures were, on average, 2.4 and 1.0 °C cooler than open-field temperatures for south and north-west aspects, respectively. Overall, the temperature offset became more negative (that is, lower under-canopy temperatures at the treeline) as the open-field temperature increased, and more positive (that is, higher under-canopy temperatures at the treeline) as the open-field temperature decreased. The buffering effect was particularly evident for the treeline on the south-facing slope, where cooling of near-ground temperature was as high as 8.6 °C for the maximum temperature (in August the offset peaked at 10 °C) and as high as 2.5 °C for the average temperature. In addition, compared to the south-facing slope, the northern site exhibited less decoupling from free-air environment conditions and low variability in microclimate trends that closely track the free-air biophysical environment. Although such a decoupling effect cannot wholly isolate forest climatic conditions from macroclimate regional variability in the south-facing treeline, it has the potential to partly offset the regional macroclimatic warming experienced in the forest understory due to anthropogenic climate change.
Ailanthus altissima
is an aggressive invasive tree worldwide, but the ecological factors that lead to the spread of this species in Mediterranean ecosystems are still unclear. Here we aim to identify ...such factors, focusing on the interaction of human activity with climatic conditions. We determined the occurrence and abundance of
Ailanthus
in 240 sites and studied their relationship with 20 variables representing climatic, geographic, and topographic factors, as well as land use, in the region of Campania (southern Italy). Overall, we found that temperature and rainfall in Campania are suitable for
Ailanthus
, with the only major constraint being the temperature at an altitude exceeding 900 m a.s.l.. We found that
Ailanthus
is unable to spread where the mean annual temperature is lower than 11.1 °C. By contrast, precipitation variables showed poor correlation with
Ailanthus
distribution, suggesting that rainfall in the selected study sites is suitable to sustain the growth of this tree. About land use variables, roads were the primary landscape feature along which this species spread and invaded new areas. Roads probably combine high propagule pressure and favorable growing conditions in terms of available resources i.e., light, water, and mineral nutrients, that allow
Ailanthus
to establish and spread along roadside edges in different ecosystems. In conclusion, we found that climate and human-associated variables are correlated with the current occurrence of
Ailanthus
, with the temperature being more influential at high elevation sites and road distance playing a prominent role in low elevation areas.
Many mushroom-forming fungi can develop circular colonies affecting the vegetation in a phenomenon named fairy rings. Since the nineteenth century, several hypotheses have been proposed to explain ...how fairy ring fungi form ring-like shapes instead of disks and why they produce negative or positive effects on the surrounding vegetation. In this context, we present a novel process-based mathematical model aimed at reproducing the mycelial spatial configuration of fairy rings and test different literature-supported hypotheses explaining the suppressive and stimulating effects of fungi on plants. Simulations successfully reproduced the shape of fairy rings through the accumulation of fungal self-inhibitory compounds. Moreover, regarding the negative effects of fungi on vegetation, results suggest that fungal-induced soil hydrophobicity is sufficient to reproduce all observed types of fairy rings, while the potential production of phytotoxins is not. In relation to the positive effects of fungi on plants, results show that the release of phytostimulants is needed to reproduce the vegetation patterns associated to some fairy ring types. Model outputs can guide future experiments and field work to corroborate the considered hypotheses and provide more information for further model improvements.
Organic Amendments (OAs) has been used in agroecosystems to promote plant growth and control diseases caused by soilborne pathogens. However, the role of OAs chemistry and decomposition time on plant ...growth promotion and disease suppression is still poorly explored. In this work, we studied the effect of 14 OAs at four decomposition ages (3, 30, 100, and 300 days) on the plant-pathogen system Lactuca sativa-Rhizoctonia solani. OAs chemistry was characterized via 13C-CPMAS NMR spectroscopy as well as for standard chemical (i.e. N content, pH, EC) and biological parameters (i.e. phytotoxicity and R. solani proliferation bioassay). OAs have shown variable effects, ranging from inhibition to stimulation of Lactuca sativa and Lepidium sativum growth. We recorded that N rich OAs with high decomposability were conducive in the short-term, while converting suppressive in the long term (300 days). On the other hand, cellulose-rich OAs with high C/N ratio impaired L. sativa growth but were more consistent in providing protection from damping-off, although this property has significantly shifted during decomposition time. These results, for the first time, highlight a consistent trade-off between plant growth promotion and disease control capability of OAs. Finally, we found that OAs effects on growth promotion and disease protection can be hardly predictable based on the chemical characteristic, although N content and some 13C CPMAS NMR regions (alkyl C, methoxyl C, and carbonyl C) showed some significant correlations. Therefore, further investigations are needed to identify the mechanism(s) behind the observed suppressive and conducive effects and to identify OAs types and application timing that optimize plant productivity and disease suppression in different agro-ecosystems.
Environmental DNA consists of species‐specific intracellular and extracellular fractions, whose content and information may not be similar in all environments. In forest soil, in particular, the ...biogeochemical fate of DNA originated by plant litter input has been extensively reviewed, but species‐specific persistence and distribution still await to be quantified. In the present work, based on the purification of extracellular and intracellular DNA fractions from forest soil samples representing 3 soil horizons at 36 randomized locations differing for stand composition (either beech‐ or spruce‐dominated, and mixed), followed by exDNA metabarcoding with the rbcL marker, we provide a clear picture of species‐specific plant DNA distribution, and explore plant community composition and diversity along the explored gradient and the soil profile. We did not find significant differences in intra‐ vs. extracellular total DNA distribution, with a progressive depletion with soil depth positively associated with soil organic C and N content and negatively associated with soil pH and mineral content. Species‐specific DNA distribution was horizontally dependent on beech and spruce basal area aboveground, while extracellular DNA showed peculiar species‐specific vertical patterns. Proportion of Fagus sylvatica DNA increased with depth in beech stand soil, and Picea abies DNA decreased in spruce stand soil, respectively, possibly linked to species‐specific differences in leaf litter decomposition dynamics and root litter contributions. Finally, our approach by metabarcoding provided a faithful, although incomplete, picture of the local plant diversity, suggesting that such technique could positively integrate traditional biodiversity inventory studies based on expert field assessments.
Extracellular DNA in forest soil declines with depth reflecting organic C turnover. Beech and spruce DNA vertical distributions in soil follow species‐specific patterns, as related to litter and soil traits. Litter decomposition and water dynamics control plant DNA persistence below ground. DNA metabarcoding provides reliable taxonomic inventories of forest plant community.
Dittrichia viscosa
is a perennial small shrub belonging to the Compositae family (Asteraceae) widespread in the Mediterranean basin. This plant has been extensively used in traditional medicine since ...the Roman times as reported by the Roman Naturalist Gaius Plinius Secundus. Nowadays, many studies about chemical composition and biological activity of
D. viscosa
are available. Chemical analyses of plant extracts revealed the presence of several metabolites belonging to different classes of natural products such as sesquiterpenes, flavonoids and caffeic acids. In addition, the essential oil of
D. viscosa
is rich in volatile short chain metabolites with aldehydes, alcohols and esters functional groups, as well as long chain fatty acids esters and alkyls. Some of these compounds are known for their biological activities against a wide range of micro- and macroorganisms. Scientific evidence reported that derivates of caffeic acids and flavonoids were the compounds mainly related to inhibition of bacterial and fungal growth, whereas sesquiterpene lactones and eudesmane sesquiterpenes were most active against nematodes, mites, insects and parasitic plants. In this paper, information about the phytochemical composition and the biological activity of
D. viscosa
against bacteria, fungi, nematodes, mites, insect and parasitic plants have been summarized.
Background
Fagus sylvatica
forms the treeline across the Apennines mountain range, with an average elevation of 1589 m a.s.l. Previous studies evidenced that the current position of the treeline in ...the Apennines is heavily depressed as a result of a complex interaction between climatic factors and the past human pressure. In this study we correlated treeline elevation in the fifteen major mountain groups in the Apennines with selected climatic, geomorphological, and human disturbance variables in order to investigate in detail the site-specific features affecting the current treeline distribution.
Results
Treeline elevation was lowest in the North Italy (Apuan Alps), while the highest treeline was found in Central Italy (Simbruini). An absolute maximum treeline elevation of
F. sylvatica
exceeding 2000 m a.s.l. was found on 13 mountain peaks in Central and Southern Italy. Noteworthy, treeline elevation was largely lower on warmer south-facing slopes compared to northern slopes, with values several hundred meters lower in the Gran Sasso and Velino-Sirente. Although the causes of this pattern are still unknown, we argue that treeline elevation on south-facing slopes may be limited by the combination of climatic constraints (i.e. summer drought) and human disturbance. Evidence of a pervasive anthropogenic effect depressing treeline elevation was found in the North (Apuan Alps) Central (Gran Sasso, Velino-Sirente, Sibillini) and Southern part of Apennines (Pollino). By contrast, treeline elevation of the Laga, Simbruini, and Orsomarso mountain groups appears less affected by past anthropogenic disturbance. Finally, we recorded in the several mountain groups (i.e. Majella, Marsicani and Pollino) the coexistence of very depressed treelines just a few kilometers away from much higher treelines, among the highest ever recorded for
F. sylvatica
.
Conclusions
Finally, we argue that
F. sylvatica
treeline across the Apennines is locally shaped both by the interaction of low temperatures experienced by the species in its earliest life stages in snow-free open spaces with summer soil water depletion and human disturbance.
Past anthropogenic disturbances lowered the altitudinal distribution of the Mediterranean
Fagus sylvatica
forests below 2,000 m a.s.l. Accordingly, our current understanding of the southern ...distribution range of
F. sylvatica
forests is restricted to managed stands below this elevation, neglecting relic forests growing above. This study has shed light on the structure and species assemblage of an unmanaged relict subalpine
F. sylvatica
stand growing within the core of its southernmost glacial refugia and at its highest species range elevation limit (2,140 m a.s.l.) in southern Apennines (Italy). Here, tree biometric attributes and understory species abundances were assessed in eight permanent plots systematically positioned from 1,650 to 2,130 m a.s.l. In the subalpine belt,
F. sylvatica
had formed a dense clonal stem population that was layered downward on the steepest slopes. The density and spatial aggregation of the stems were increased, while their stature and crown size were decreased. Above 2,000 m, changes in tree growth patterns, from upright single-stemmed to procumbent multi-stemmed, and canopy layer architecture, with crowns packed and closer to the floor, were allowed for the persistence of understory herbaceous species of biogeographic interest. Clonal layering represents an adaptive regeneration strategy for the subalpine belt environmental constraints not previously recognized in managed Mediterranean
F. sylvatica
forests. The clonal structure and unique species assemblage of this relic forest highlight the value of its inclusion in the priority areas networks, representing a long-term management strategy of emblematic glacial and microclimatic refugia.
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