Sporocarp Community Research Articles

Macrofungal sporocarp community in the lichen Scots pine forests.

The lichen-rich pine forests of Cladonio-Pinetum represent special habitats protected under the Natura 2000 scheme. A rapid decline in their density has been observed in recent years. Macrofungi are an important component of the community and sensitive bioindicators; therefore, observations of the response of their sporocarps can be used to draw conclusions about changes induced in habitats. In our study, we tried to detect differences in species richness, composition, and biomass of the ectomycorrhizal fungal communities in areas rich in lichens indicating the good state of the community, and rich in bryophytes signaling its progressive degradation. The influence of precipitation and temperature on species richness and biomass was checked, and the possibility of using the sporocarps-based method to assess the effectiveness of active protection treatments, which are a form of partial protection carried out to maintain specific natural habitats. For detailed studies, six plots were selected from which sporocarps were collected, dried and weighed. A total of 1,575 sporocarps, representing 49 taxa were collected. A higher number of taxa (39) in lichen-rich plots were found. In bryophyte-rich areas, 27 taxa were recorded. The total yield was 13,151 g dry weight ha-1. In lichen-rich plots, the biomass was almost half lower.

Do aquatic fungal environmental DNA assemblages reflect the surrounding terrestrial sporocarp communities?

The relationship between aquatic environmental DNA (eDNA) assemblages in rivers and the surrounding terrestrial fungal communities has been poorly investigated. Here, we focused on fungi that form soft sporocarps (soft fungi). Two years of sporocarp and aquatic eDNA sampling were conducted at a fragmented forest site, and the soft-fungal assemblages and their temporal dynamics were compared between these two sample types. Aquatic eDNA yielded approximately 1.5 times the operational taxonomic units (OTUs) compared to sporocarps and covered approximately half of the OTUs from sporocarp samples. Lineages that seldom form sporocarps or form inconspicuous sporocarps were successfully detected from aquatic eDNA. Although the OTU composition differed between sporocarp and aquatic eDNA, their temporal dynamics were similar, with both showing a 1-year periodicity. Aquatic eDNA provides insights into fungal diversity and temporal dynamics, but does not fully reflect terrestrial fungi diversity.

Fungal sporocarp productivity and diversity shaped by weather conditions in Pinus uncinata stands

Pinus uncinata is a species frequently growing in the tree line limit of southwestern European subalpine ecosystems, hosting fungal communities that provide relevant ecosystem services. Despite the high importance of these forests for conservation, limited prior research has analysed the sporocarp fruiting patterns. This study aims at filling this gap in knowledge by describing interannual changes in sporocarp productivity, diversity, and community composition over 5 years and identifying possible relationships with the main weather and soil physicochemical characteristics. The studied P. uncinata stands had an average annual total sporocarp productivity of 21.60 kg ha-1yr−1 in dry weight, hosting a total of 255 species with productivity-dominant ectomycorrhizal families such as Russulaceae and Tricholomataceae that occurred mostly from mid-August to end September. In contrast, saprotrophs showed more stable productivity values from mid-August to end of November with average annual sporocarp productivity of 1.76 kg ha-1yr−1 in dry weight but exhibited higher fungal richness values from the start of October until the end of November. Fungal productivity and species richness were mostly influenced by weather conditions while soil physicochemical properties had implications in shaping the sporocarp community composition. This study quantifies the interannual fungal fruiting pattern of the understudied fungal communities and underlines the importance of climatic variables in shaping fungal fruiting patterns within a climate change context. In addition, this work is also of special relevance since P. uncinata ecosystems represent the tree line limit, which makes this species and its associated fungal communities especially sensitive to the potential impacts of global warming.

Environmental drivers shaping the macrofungal sporocarp community in Mediterranean Quercus ilex stands

Holm oak is one of the most abundant tree-forming species in the Mediterranean area, hosting a great number of fungal species that are fundamental for the functioning of these forest ecosystems. However, the information about the fungal communities growing in Quercus ilex stands and the environmental drivers shaping their fruiting patterns is still scarce. This study aimed to characterize the productivity, diversity, and community composition of macrofungal sporocarps growing in Mediterranean Quercus ilex stands as shaped by key environmental drivers including meteorological and soil variables. We analysed a data set obtained from the autumn weekly sampling of all macrofungal sporocarps from 8 permanent plots over 13 consecutive years, and related weather and soil variables. We built up several linear mixed-effects models to describe productivity and richness changes over time, in addition to multivariate analyses aiming to describe the community composition variations. We identified 241 macrofungal species that were predominantly ectomycorrhizal, with Russulaceae and Cortinariaceae being the most abundant families. Agaricaceae and Tricholomataceae were the most abundant families of saprotrophic fungi. In addition, soil properties such as pH, organic matter and sand content played a significant role in sporocarp community composition. Our results highlight different drivers shaping different fungal fruiting processes, i.e., weather variables drive sporocarp productivity and sporocarp richness while soil characteristics may have a stronger influence on the aboveground fungal community composition. This study illustrates the high stochasticity of sporocarp occurrence and productivity, with species exhibiting higher values whenever the meteorological conditions were suitable for fungal fruiting.

Seasonal disconnects between saprobic and mycorrhizal sporocarp communities in the Southern Appalachian Mountains

The southern Appalachian Mountains in the United States are heavily forested with diverse forest types and vegetation structures and is generally considered a biodiversity hotspot. Fungal sporocarp investigations in this region are not new, but multi-year interseasonal investigations into sporocarp community patterns are rare. Using a 4-year (2014–2017) repeated monthly macrofungal sampling dataset (May–October) across an elevational gradient (associated with vegetation structure), we queried community, seasonal, and guild community ecological patterns. In doing so, we (1) demonstrate a temporal disconnect between saprobic and ectomycorrhizal taxa, (2) describe increased community variability across the growing season, and (3) explore individual taxa occurrences across seasons and examine co-occurrence patterns between taxa and guilds. Further, we explore congruence between sporocarp and metabarcoding fungal datasets and advocate the utility of both sampling schemes.

Impact of forest thinning on aboveground macrofungal community composition and diversity in Mediterranean pine stands

Fungal communities are especially relevant in Mediterranean regions, a ‘hotspot’ of fungal diversity, and where the value of edible commercial sporocarps may be much higher than the income from timber products. Assessing the effects of forest management practices together with the modulating role of climate on sporocarp community composition and diversity is crucial for understanding their impacts on fungal-related ecosystem services. Yet, previous research on forest management impacts on aboveground fungal diversity and community composition is scant, sometimes contradictory and mainly focused on rather short-term impacts. We quantified the long-term response of the sporocarp community composition and diversity to different forest thinning intensities in Mediterranean Pinus pinaster forest stands, and the interactions with weather conditions in modulating the fungal response. We relied on 28 permanent plots representing a thinning intensity gradient, monitored for sporocarp diversity on a weekly basis during eleven consecutive years. Weather conditions of each plot were obtained through interpolation from different meteorological stations. Overall, the fungal sporocarp community composition showed short-term (<2 years) changes mainly under both heavy and light thinning intensities compared to unthinned plots. The unexpected compositional change caused by light thinning intensities affected only certain ectomycorrhizal fungi (Lactarius group deliciosus). Climatic factors, mostly the mean temperature of September and October, contributed to enhancing or diminishing the compositional response of macrofungi to forest thinning. Moreover, there was no effect of forest thinning on sporocarp species diversity (i.e., richness and evenness). Both ectomycorrhizal and saprotrophic species richness and ectomycorrhizal species evenness increased over time. Our results indicate that the post-treatment conditions following forest thinning may cause short-term successional changes in both ectomycorrhizal and saprotrophic fungal assemblages, benefiting, in turn, particular fungal species of socioeconomic interest by producing large amount of sporocarps. Furthermore, forest thinning with careful and low-impact removal of trees does not jeopardize sporocarp diversity.

Large, high-severity burn patches limit fungal recovery 13 years after wildfire in a ponderosa pine forest

Over the past three decades, wildfires in southwestern US ponderosa pine (Pinus ponderosa Lawson & C. Lawson) forests have increased in size and severity. These wildfires can remove large, contiguous patches of mature forests, alter dominant plant communities and increase woody debris, potentially altering fungal community composition. Additionally, post-fire conditions may shift dominant fungal functional groups from plant-symbiotic ectomycorrhizal (EM) fungi to more decomposer saprotrophic fungi. We investigated the long-term (13 years post-wildfire) effect of fire severity on 1) fungal sporocarp density, functional groups and community composition and 2) EM colonization and community composition from naturally regenerating ponderosa pine seedlings on the Pumpkin Fire that burned in 2000 in Arizona, USA. Plots were located in four burn severity classes: unburned, moderate-severity, and two high-severity (defined as 100% tree mortality) classes, either adjacent to residual live forest edges (edge plots), or >200 m from any residual live trees (interior plots). We found that high-severity burn plots had a unique sporocarp community composition, and a shift in dominant sporocarp functional groups, with 5–13 times lower EM sporocarp densities, and 4–7 times lower EM sporocarp species richness compared to unburned and moderate-severity plots. In contrast, saprotrophic sporocarp densities and richness were similar among burn severity classes, even with the large amount of coarse wood in the high-severity burn patches. Regenerating ponderosa pine seedlings had similar EM colonization and richness among severity classes, yet high-severity interior plots had a different community composition and a lower relative abundance of EM species compared to moderate-severity burn plots. Taken together, our results suggest that large patches of high-severity fire have long-term consequences for both EM sporocarp and root tip communities. Because EM fungal species vary in function, the limited species pool available in interior high-severity burn patches may influence pine recovery.

Climate impacts on fungal community and trait dynamics

Abstract Although climate change and variability can impact fungal phenology, the effects on community composition are less understood. Additionally, climatic variability might modify trait selection in fungi, including spore size and dispersal characteristics. Compositional and trait modifications of fungal communities would have important consequences for fungal biogeography, interactions with plant communities, and ecosystem functions. In this study, we analysed long-term fungal sporocarp community structure and dynamics in response to climate change and variability. We tested whether observed changes in the fungal sporocarp community related to climate, temporal or spatial differences among plots. Fungal trait associations with climatic variables were tested. Climate and endogenous patterns of succession each significantly affected composition, with regional variance in the affecting climate variables. Evidence for climate-driven reproductive trait selection related to spore dimensions, spore-bearing surfaces, and mode of fungal nutrition. Future research should then prioritize examining the impacts of climate on spore production and dispersal, plus other fungal traits.

Long-term monitoring reveals a highly structured interspecific variability in climatic control of sporocarp production

Abstract Understanding factors triggering fungal sporocarp productivity responses to climate at an individual species level is critical to predicting future species composition and abundance under global climate change scenarios. Different climatic responses at a species level may lead to shifts in species turnover and in the relative contributions of different species, which may in turn have strong impacts on community functional attributes. We used sporocarp production data compiled over 15 years of weekly sampling during the mushroom fruiting season in a continental Mediterranean climate pine forest to estimate: (i) the interspecific variability on the climatic factors constraining fungal sporocarp productivity, (ii) the relationship of this variability linked to mushroom phenology and trophic guilds, and (iii) the impact of different species responses on sporocarp community composition and diversity under projected climate change scenarios. Fungal fruitbody production was closely correlated with climatic conditions throughout the year, indicating that sporocarp development may be controlled by processes occurring well before the fruiting season. The large interspecific variability in the climatic factors controlling sporocarp production was highly structured with differences inlength of the temporal window controlling this process, and the timing of the summer-autumn rainfall climatic signal being the most relevant factors. Climatic response was unrelated to fungal phenology or trophic guild. When individual models are applied to future climate scenarios (2021–2080), they predict a decrease in total sporocarp productivity, which agrees with community based models, as well as a shift in community composition, leading to less species-diverse assemblages.

Elevated CO2 and O3 effects on ectomycorrhizal fungal root tip communities in consideration of a post-agricultural soil nutrient gradient legacy.

Despite the critical role of EMF in nutrient and carbon (C) dynamics, combined effects of global atmospheric pollutants on ectomycorrhizal fungi (EMF) are unclear. Here, we present research on EMF root-level community responses to elevated CO2 and O3. We discovered that belowground EMF community richness and similarity were both negatively affected by CO2 and O3, but the effects of CO2 and O3 on EMF communities were contingent on a site soil pH and cation availability gradient. These results contrast with our previous work showing a strong direct effect of CO2 and O3 on sporocarp community dynamics and production. We discuss the possible role of carbon demand and allocation by EMF taxa in the discrepancy of these results. EMF communities were structured by a legacy of spatially defined soil properties, changing atmospheric chemistry and temporal dynamics. It is therefore necessary to understand global change impacts across multiple environmental gradients and spatiotemporal scales.

Truffle-like fungi sporocarps in a eucalypt-dominated landscape: patterns in diversity and community structure

Truffle-like fungi are highly diverse yet poorly known in Australia. To assess the species richness, biomass, and community assemblages of truffle-like fungi in different habitats we sampled sporocarps of truffle-like fungi in three eucalypt-dominated forest types (grassy woodland, wet sclerophyll forest, and dry sclerophyll forest) once in summer and once in winter, at two sites (Mount Kaputar and New England) in northern New South Wales, Australia. One hundred and eighteen species in 35 genera were collected; over half (51.7 %) of the species were undescribed. Grassy woodland and wet forest communities had greater species richness and a lower standing crop than dry forest communities. Species richness and standing crop was greater in winter than in summer. Overall, species from the family Russulaceae, and the genera Dermocybe, Descomyces, and Hysterangium were dominant. Community composition varied among forest types and each forest type exhibited a suite of unique and common species, although much variation was unexplained. Variation in community structure was associated with some habitat attributes; at Mount Kaputar, woody plant species richness, canopy cover, litter depth, soil phosphorous, and elevation helped explain the sporocarp communities of different forest types, while at New England, woody plant species richness, rainfall, topographic aspect, soil texture, and soil nitrogen helped explain communities. This work contributes to knowledge of truffle-like fungal diversity, the factors affecting sporocarp distribution across landscapes, and the availability of sporocarps as a food resource for mycophagous mammals. Greater understanding of fungal diversity and mammal-fungal interactions also has important implications for managing forest biodiversity.

Differential hypogeous sporocarp production from Nothofagus dombeyi and N. pumilio forests in southern Argentina

Mycorrhizal fungi that form hypogeous sporocarps are an important component of the temperate forest soil community. In many regions, such as the Nothofagus forest in the Patagonian Andes, this group of fungi has been poorly studied. Here we examined the spring and autumn community composition of “sequestrate fungi”, based on sporocarp production in pure forests of Nothofagus dombeyi (evergreen) and N. pumilio (deciduous). We investigated the possible relationships between these communities and environmental factors over 2 y. The rarefaction curves and the minimal richness estimates converged at nearly the same level for each forest type, and the asymptotes suggested that the sampling effort was sufficient to capture most of the hypogeous sporocarp richness in these forest stands. In total 27 species were recovered. Basidiomycota, Ascomycota and Glomeromycota respectively accounted for nine, two and one genera. Species richness of hypogeous sporocarps varied in relation to forest type but not to season (fall and spring), whereas sporocarp biomass varied according to an interaction between season and forest type. Species richness and sporocarp biomass were positively correlated with rainfall and negatively correlated with altitude. In addition sporocarp species richness was positively related to number of trees per transect. We found that two different forest stands, each dominated by different species of Nothofagus, exhibited different hypogeous sporocarp communities.

Changes in community structure of ectomycorrhizal fungi associated with Pinus montezumae across a volcanic soil chronosequence at Sierra Chichinautzin, Mexico

Ectomycorrhizal (ECM) communities of Pinus montezumae Lamb. var. montezumae were studied across a volcanic soil chronosequence at Sierra del Chichinautzin, Mexico, to investigate differences in community structure at sites with different soil quality. Study sites were located on volcanic soils of different ages. Both aboveground and belowground fungal communities were compared for 3 years. Species abundance, richness, and diversity were compared among sites. Significant differences were found among the three sites for sporocarp abundance and biomass but not for total ECM root tips. The more diverse sporocarp community was found at the youngest, less fertile site. Dominant species at the sporocarp and ECM morphotype levels differed across the chronosequence. The largest proportion of sporocarp species was site-exclusive, which suggests that aboveground communities depend upon soil conditions. Contrarily, 85% of ECM morphotypes were present at least at two sites. The poor correspondence between the aboveground and belowground views of the ECM fungal community may be due to differences in sampling methodology and level of identification. Inocybe and Laccaria species were abundant fruiters at all sites, and as multisite fungi, they may be tested for inoculum efficiency to be used in reforestation programs in the surroundings of Mexico City.

Stand age and sampling year effect on the fungal fruit body community in Pinus pinaster forests in central Spain

The process of fungal community succession in forests is still insufficiently known, especially in Mediterranean ecosystems. To reveal successional patterns, we studied changes in aboveground sporocarp composition in managed Pinus pinaster Ait. forests across a stand age chronosequence from 5 to more than 90 years in Soria province (Central Spain). We evaluated the effect of yearly conditions and stand age on species richness, composition, and trophic groups. All aboveground sporocarps were collected and identified in 21 plots, each measuring 150 m2, placed in a random stand age-stratified survey. Sampling was performed weekly in the autumn during 6 years (1997–2002). The effect of year and stand age on species richness was analysed using repeated measures analysis of variance and change in composition. Changes in community composition were evaluated via canonical correspondence analysis (CCA). The response of different trophic groups was analyzed using ANOVA with age as a fixed factor. Fungal community richness increased with stand age. This increase was related to the rise in humicolous saprotroph and mycorrhizal species. The presence of parasitic and lignicolous fungi was always very low, probably as a result of forest management. Yearly conditions exerted a stronger effect than stand age on aboveground sporocarp community richness and composition.

Ectomycorrhizal fungi identification in single and pooled root samples: terminal restriction fragment length polymorphism (TRFLP) and morphotyping compared

We describe here the results of a study conducted to evaluate a terminal restriction fragment length polymorphism (TRFLP) approach targeting rRNA genes for determination of ectomycorrhizal (ECM) communities colonizing the roots of loblolly pine ( Pinus taeda L.). Root tips separated from soil cores were classified according to morphological characteristics and DNA was then extracted from each group of morphotyped tips. Labeled primers were used to generate terminal restriction fragments (TRF) for molecular fingerprinting of root colonizing fungi and to determine how well TRFLP could be used to discriminate between ectomycorrhizal types. Morphotypes generally correlated well with specific TRFs and sequence analysis confirmed that TRFs could be used to discriminate among fungal types. Sequence analysis indicated that important ECM fungi including Russulaceae, Thelephorales, and Tricholomataceae could be fingerprinted with TRFLP. In addition, a fixed proportion of the DNA extracted from each morphotype from the same core was used in a pooling experiment used to assess whether previously identified fungal species types could be distinguished from one another within reconstructed communities. Since some morphotypes share TRFs, dual analysis of ITS1 and ITS2 was necessary for accurate fingerprinting of fungal types. Approximately, 5.0±0.3 phylotypes were detected per core with TRFLP-corrected morphotyping as compared to 4.0±0.4 phylotypes using TRFLP on pooled community samples. TRFLP made on experimental sporocarp communities suggested that reduced ECM richness with TRFLP may be partly caused by differences in the amount of DNA available for PCR and primer bias. Nonetheless, TRFLP on pooled morphotypes accounted for more than 93% of colonized root tips. The method can be used to facilitate analysis of mycorrhizal communities using root tips collected from soil cores.

BELOWGROUND ECTOMYCORRHIZAL FUNGAL COMMUNITY CHANGE OVER A NITROGEN DEPOSITION GRADIENT IN ALASKA

Nitrogen availability may be a major factor structuring ectomycorrhizal fungal communities. Atmospheric nitrogen (N) deposition has been implicated in the decline of ectomycorrhizal fungal (EMF) sporocarp diversity. We previously characterized the pattern of decreased sporocarp species richness over an anthropogenic N deposition gradient in Alaska (USA). To determine whether this change in sporocarp community structure was paralleled below ground, we used molecular and morphological techniques to characterize the ectomycorrhizal community of white spruce (Picea glauca) over this gradient. We then related patterns of richness and relative abundance of taxa to various N-affected environmental parameters. Species richness of EMF declined dramatically with increasing N inputs. Over 30 taxa were identified at the low-N sites, compared with nine at the high-N sites. Low-N site dominants (Piloderma spp., Amphinema byssoides, Cortinarius spp., and various dark-mantled Tomentella spp.) disappeared completely at th...