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Review on fire effects on ectomycorrhizal symbiosis, an unachieved work for a scalding topic

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... Moreover, ECM fungi have recently been shown to be also able to transfer substantial amount of carbon into forest soils, for long-term storage (Clemmensen et al., 2013), and consequently affect key ecosystem properties. While intensive, clear-cut harvesting is known to seriously reduce ECM fungi (Kohout et al., 2018;Parladé et al., 2019;Sterkenburg et al., 2019), the role of fire appears to be much more variable (Taudière et al., 2017;Salo and Kouki, 2018). ...
... Most of the more recent studies have explored ECM and WAM fungi, particularly aphyllophoroid species. Fires often reduce the amount of fungi in these groups, but the overall effects are still hard to identify (Taudière et al., 2017). ...
... In burned and unharvested sites, the diversity and biomass of ECM species did not systematically differ from unburned control sites. Previous studies on ECM and fire have provided contrasting results (reviewed by Taudière et al., 2017). ...
... A recent review work on the effects of forest fire on fungal association reveal that fungal-fire relations studies were mostly located in temperate and Mediterranean forest ecosystems (Taudière et al., 2017). The tropical forests are yet understudied, and comprehensive studies are recommended to improve understanding of the fungi-fire relationships with current global scale changes. ...
... The negative effect of fire on sporocarp production has been investigated in previous studies by Hart et al. (2005), Bastias et al. (2006), Cairney and Bastias (2007), Hernández-Rodríguez et al. (2013); and Mediavilla et al. (2014) from multiple geographical areas. Post fire fruiting and the relative effects of fire on fungi fruiting, with a special emphasis on the saprophytic species are also deeply reviewed (Taudière et al., 2017). In the present study lower fungal production was also collected from recently burned stand. ...
... The absence of difference in sporocarp production between a recently burned and an unburned stands was previously reported by Mediavilla et al. (2014) who studied the effect of fire on saprophytic species associated to Pinus nigra stands in the Mediterranean. This could be explained by the existence of fungal species whose ephemeral fruit bodies may cover forest soil in recently burned areas (Hart et al., 2005;Taudière et al., 2017), taking advantage of the condition created (Bean et al., 2009). For example, Armillaria sp. ...
Article
Fire is among the main threats to forest ecosystems in Ethiopia and is affecting the forest biodiversity, including fungal communities. This study was aimed to examine the effects of fire on macrofungal taxa richness, diversity and sporocarp production in the Dry Afromontane forests in Ethiopia. Sporocarps were collected from nine plots (100 m 2) established in one-and ten-year-old burned stands, and in an unburned stands. The data were used to quantify fungal richness and sporocarp fresh weights. Morphological and molecular analyses were used to identify the fungi. Composite soil samples were also collected from each stand and used to determine main edaphic explanatory variables for taxa composition. A total of 61 fungal taxa, belonging to Basidiomycota division were reported, of which 22 were edible. Fungal diversity, richness and sporocarp production were affected just after the fire. Fungal community composition was significantly correlated with Organic matter, P and Ca. Generally, the result is encouraging from the point of view of fungal conservation. It provides novelty information about the macrofungal communities in Ethiopian dry Afromontane forests, likely including many taxa are still unknown to science as well as several edible species which could supply complementary incomes for the rural populations in the study area.
... In western North America these beneficial fungi are critical in the establishment and survival of conifers in low nitrogen soils (Mayor et al. 2015;Hawkins et al. 2015). Fire is an important feature of western conifer forests that impacts both ectomycorrhizal fungi and soil properties (Neary et al. 1999;Certini 2005;Cairney and Bastias 2007;Taudière et al. 2017). Fire can wipe out or alter ectomycorrhizal communities (Stendell et al. 1999;Grogan et al. 2000;Dahlberg et al. 2001;Treseder et al. 2004;Smith et al. 2005) and decrease fungal propagules in the soil (Bruns et al. 2002b;Izzo et al. 2006;Peay et al. 2009;Jones et al. 2010;Kipfer et al. 2010;Glassman et al. 2016). ...
... Fire impacts on ectomycorrhizal communities can persist for years (Treseder et al. 2004;Taudière et al. 2017), yet seedlings depend on ectomycorrhizal fungi for establishment (Ortega et al. 2004;Quoreshi et al. 2009). These beneficial fungi enhance nutrient uptake and access forms of nutrients otherwise unavailable to woody plants (Chalot and Brun 1998;Landeweert et al. 2001;Hobbie and Högberg 2012) which is of particular importance on burns. ...
... This was surprising although the burn was severe and the result of an intense fire; only standing dead and minimal understory regeneration were observed two years after the fire and soil was only collected to a depth of 20 cm. Dahlberg et al. (2001) found almost no mycorrhizas on roots 15 cm deep on a severe burn site in Sweden, and intense fire has been reported to decrease root colonization in a number of studies (Taudière et al. 2017). Site properties can also impact the fungi (Kennedy et al. 2015) and many of the P. albicaulis trees in the area are dead, killed by mountain pine beetles in the last decade (MacFarlane et al. 2013). ...
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Aims In western North America ectomycorrhizal fungi are critical to establishment of conifers in low nitrogen soils. Fire can affect both ectomycorrhizal fungi and soil properties, and inoculation with ectomycorrhizal fungi is recommended when planting on burns for restoration. The aim of this study was to examine how Suillus species used in inoculation affect whitebark pine (Pinus albicaulis L.) seedlings planted in fire-impacted soil. Methods In a greenhouse experiment, Suillus-colonized and uncolonized whitebark pine seedlings were planted in unsterilized and sterilized (control) soil from a recent burn. After 6 months, foliar nitrogen and carbon content, concentration, and stable isotope values were assessed, along with growth parameters. Results When seedlings were colonized, biomass was 61% greater, foliar nitrogen content 25% higher, foliar nitrogen concentration 30–63% lower; needles had lower δ¹⁵N and higher δ¹³C. Differences were more pronounced in sterilized soil where colonization was higher. Foliar N content was negatively correlated with δ¹⁵N values. Conclusions Colonization by host-specific fungi produced larger seedlings with higher foliar nitrogen content in both burn soils. The hypothesis that ectomycorrhizal fungi on roots fractionate nitrogen isotopes leading to lower δ¹⁵N in needles is supported. This helps explain restoration outcomes, and bridges the gap between field and in vitro investigations.
... Various studies have demonstrated both direct and indirect effects of fire on the EMF community while consequently influencing the post-fire regeneration of the plant community (Buscardo et al. 2010;Glassman et al. 2016;Johnson 1995;Marlon et al. 2009;Miller and Urban 1999;Taudière et al. 2017;Veen et al. 2008). Although such effects are expected to be related to fire severity, which often varies during the year, less is known about the specific effect of fire season on the EMF community. ...
... First, we could not detect a significant effect of fire on EMF richness or diversity. This result is in contrast to most studies of prescribed burns, illustrating a negative effect of fire on EMF richness (Taudière et al. 2017). Second, late-dry season (autumn) burns affected EMF community composition, but these differences between the control and autumn (late-dry season) burned plots faded quickly and had disappeared by the next sampling period (Table 1). ...
... We observed the largest differences due to fire season in the total soil fungal community, rather than in the EMF community, and this effect was largely driven by changes within the saprotrophic fungal guild. Most data on fungal response to fire comes from northwestern USA (Taudière et al. 2017), where fires are typically of higher severity than in the eastern Mediterranean basin. Such fires, as those attained in our study, are less likely to lead to host dieback, or to inflict direct damage to soil microorganisms. ...
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Fire effects on ecosystems range from destruction of aboveground vegetation to direct and indirect effects on belowground microorganisms. Although variation in such effects is expected to be related to fire severity, another potentially important and poorly understood factor is the effect of fire seasonality on soil microorganisms. We carried out a large-scale field experiment examining the effects of spring (early-dry season) versus autumn (late-dry- season) burns on the community composition of soil fungi in a typical Mediterranean woodland. Although the intensity and severity of our prescribed burns were largely consistent between the two burning seasons, we detected differential fire season effects on the composition of the soil fungal community, driven by changes in the saprotrophic fungal guild. The community composition of ectomycorrhizal fungi, assayed both in pine seedling bioassays and from soil sequencing, appeared to be resilient to the variation inflicted by seasonal fires. Since changes in the soil saprotrophic fungal community can directly influence carbon emission and decomposition rates, we suggest that regardless of their intensity and severity, seasonal fires may cause changes in ecosystem functioning.
... Some studies also show that low-intensity fires do not seem to significantly affect ectomycorrhizal community richness (Jonsson et al., 1999). Overall, thus, the effects of fire on fungi assemblages and their mutualistic association with trees appear to vary remarkably after forest disturbances but this variation is not well understood (for a recent review, see Taudiere et al., 2017). ...
... Based on a recent review, majority of wildfire influences on ECM appear to be detrimental (Taudiere et al., 2017). Unfortunately, it is very rare that ECM studies can address the influence of variable fire severities using relatively long-term monitoring. ...
... Temporal dynamics of ECM recovery after wildfire shows strikingly different patterns in previous studies (reviewed in Taudiere et al., 2017). It is quite likely that the variability is closely related to fire severity, and our results support this. ...
... Soil fungi can alter host plant nutrient and water acquisition (Despain, 2001;Smith & Read, 2008) and contribute to ecological functions like carbon and nutrient cycling (Shah et al., 2016). Furthermore, bark beetle outbreaks Pec et al., 2017;Treu et al., 2014), wildfire (Buscardo, Freitas, Pereira, & de Angelis, 2011;Taudière, Richard, & Carcaillet, 2017), logging (Jones, Durall, & Cairney, 2003;Kohout et al., 2018) and salvage logging (Ford, Kleinman, & Hart, 2018;Kutorga et al., 2012) can potentially alter soil fungal communities in coniferous forests. ...
... Environmental conditions important to soil fungi such as soil pH, moisture, nutrients, phenolics and host plant composition can change with disturbance, and thus can alter fungal communities (Goldmann et al., 2015;Kutorga et al., 2012;Pec et al., 2017;Taudière et al., 2017). For example, processes like nutrient cycling differ following MPB outbreak versus wildfire as a result the latter may impose a biotic filter that favours soil fungal communities that respond well to high mineral nutrients in the soil while soil fungal communities following MPB may be better suited to high levels of soil phenolics (Buscardo et al., 2011;Cigan et al., 2015;Pec et al., 2017;Taudière et al., 2017;Treu et al., 2014). ...
... Environmental conditions important to soil fungi such as soil pH, moisture, nutrients, phenolics and host plant composition can change with disturbance, and thus can alter fungal communities (Goldmann et al., 2015;Kutorga et al., 2012;Pec et al., 2017;Taudière et al., 2017). For example, processes like nutrient cycling differ following MPB outbreak versus wildfire as a result the latter may impose a biotic filter that favours soil fungal communities that respond well to high mineral nutrients in the soil while soil fungal communities following MPB may be better suited to high levels of soil phenolics (Buscardo et al., 2011;Cigan et al., 2015;Pec et al., 2017;Taudière et al., 2017;Treu et al., 2014). These changes in soil fungal communities can be critical to lodgepole pine (Karst, Randall, & Gehring, 2014;Pec et al., 2017;Smith, Douhan, Fremier, & Rizzo, 2009;Treu et al., 2014) and have cascading impacts on pine seedling biomass and secondary chemical production . ...
Article
Disturbances are frequent events across the Canadian boreal forest and can affect both below and above ground ecosystem processes. How disturbances change belowground soil fungal communities and in‐turn affect pine establishment and performance is poorly understood. Such understanding has become increasingly important in light of observed changes in disturbance regimes in recent years due to climate change. We used a greenhouse experiment to determine how soil inoculum collected from lodgepole pine stands undisturbed (control) or disturbed by fire, mountain pine beetle outbreak, logging, and salvage logging affect pine seedling performance in western Canada. We first characterized whether fungal communities of seedling roots change as a function of inoculum source, and then determined whether changes in fungal community composition impact pine seedling performance (biomass and height). Root fungal communities of pine seedlings from logged and salvage logged disturbances differed from their respective paired controls, while soils from natural disturbances (fire and beetle outbreak) did not. Among disturbances, the pine root fungal communities of fire and salvage logged disturbances differed. In parallel to the root fungal communities, seedling performance also decreased when comparing logging and salvage logging disturbances to paired controls. Among disturbance treatments, seedlings from the salvage logged disturbance did not grow as big as seedlings inoculated with soils from burned forests. Synthesis and Application. Our findings indicate that anthropogenic disturbances (logging and salvage logging) can have cross‐generational impacts on pine seedling performance, through functional shifts in seedling root fungal community structure. Furthermore, the impacts of soil fungi on pine seedlings appear to be pronounced following salvage logging, stressing the importance of compound disturbance events. These findings may be important to land managers considering clear‐cut logging or salvage logging in pine forests, particularly where soil biotic communities are likely to be one of the predominate factors in pine establishment.
... In addition, further studies are required to increase our understanding of the dynamics of soil fungi and their community structure (Dhruba et al., 2015) and the impact of various environmental and anthropogenic factors. Furthermore, to date, most studies of soil fungal communities have focussed on temperate and Mediterranean forest ecosystems; less consideration has been given to soil fungal communities in tropical forest ecosystems (Taudière et al., 2017). ...
... However, the inconsistency of results from individual studies makes it difficult to provide a general conclusion regarding the possible dynamics of fire, fungi and ecosystem function. Consequently, location-based studies are necessary to obtain a better understanding of the effect of fire on the soil fungal community at a specific location (Taudière et al., 2017). ...
Article
Ethiopian dry Afromontane forests are complex ecosystems that have important economic and ecological roles. However, recurrent fire has been a source of disturbance for these forests. We assessed the effect of fire on soil fungal communities in a remnant dry Afromontane forest in Wondo Genet, southern Ethiopia, by analysing soil samples collected from unburned stands and from stands one and ten years after fire using DNA metabarcoding of the ITS2 rDNA. The analysis indicated that the soil fungal community was most diverse soon after a fire disturbance and declined over time. Fungal community composition also differed among stands. Our results also indicated that differences in fungal diversity were stand dependent rather than due to the chronology of the fire history in this forest system. We found higher numbers of mycorrhizal species in burned stands, suggesting that these fungal symbionts could compensate for the effects of nutrient stress caused by fire in these areas. Fungal community composition was also significantly correlated with organic matter content, potassium and magnesium in soil. This work could be considered as a case study since the plots were established in a single stand for each treatment in the dry Afromontane forests of Ethiopia. Thus, we recommend further studies and conclusions regarding other stands need to be taken with caution.
... Large disturbances like wildfire, insect outbreaks, and windthrow occur naturally in the life cycles of temperate forests (Seidl et al. 2011). Because most tree species of European temperate forests live in symbiosis with ectomycorrhizal (ECM) fungi, these are also expected to be significantly influenced by natural disturbances and are possibly adapted to some extent (Jones et al. 2003;Taudière et al. 2017). Most information about the influence of natural forest disturbance on ECM fungi came from forests affected by wildfire. ...
... This finding corresponds with the analysis of dataset 2, that after quantitative differences were filtered out, there was a similar number of ECM species in the 500 sequences per subplots (Table 2). Our finding from the fire treatment disagrees with the review by Taudière et al. (2017), who reported no consequence of fire on the richness of the ECM community. In our case, the ECM fungal community affected by fire became less complex and possibly could be less resilient (Mariotte 2014). ...
Article
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Ectomycorrhizal (ECM) fungi, as symbionts of many tree species in temperate forests, are thought to play an important role in forest regeneration processes after large disturbances. Their reaction to different disturbance and management regimes was studied in spruce forests (Lariceto-Piceetum) 10 years after a severe windthrow in the Tatra National Park (Slovak Republic). ECM community structure was compared between different “management types″—cleared area (EXT), area affected by wildfire (FIRE), uncleared area left for natural development (NEX), and mature forest as a control (REF). Based on Illumina sequencing of soil samples, we determined that the percentage of sequences assigned to ECM fungi decreased with increasing disturbance and management intensity (REF → NEX → EXT → FIRE). Similarly, the total number of ECM species per each of ten sampling points per plot (100 ha) differed between managed (EXT-11 species, FIRE-9) and unmanaged (NEX-16, REF-14) treatments. On the other hand, the percentage of sequences belonging to ericoid mycorrhizal fungi increased. Management type significantly influenced the composition of the ECM community, while vegetation and soil characteristics explained less data variation. The ECM species assemblage of the unmanaged site (NEX) was the most similar to the mature forest, while that of the burnt site was the most different. Thelephora terrestris dominated in all treatments affected by windthrow, accompanied by Tylospora fibrillosa (NEX) and Tylospora asterophora (EXT and FIRE). Management regime was also the most important factor affecting ECM species composition on the roots of spruce seedlings assessed by Sanger sequencing.
... Wilhelm et al. (2017) found that soil fungal communities had long-term responses to clearcutting for decades after harvest; the relative abundances of drought-tolerant and heat-tolerant taxa increased, while EcM fungal diversity decreased. Nevertheless, comprehensive studies on soil fungal succession in wildfire chronosequences are relatively limited (Cairney & Bastias, 2007;McMullan-Fisher et al., 2011;Taudiere et al., 2017), especially in East Asia. Existing studies suggest that, in the short-term (e.g. ...
... Changes in community composition are the most frequently observed effect of wildfire on soil fungi (McMullan-Fisher et al., 2011;Taudiere et al., 2017). In this study, burning effects on fungal composition (including EcM fungi and saprotrophs) were pronounced in upper soils (Fig. 3). ...
Article
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Soil fungi represent a major component of belowground biodiversity that determine the succession and recovery of forests after disturbance. However, their successional trajectories and driving mechanisms following wildfire remain unclear. We examined fungal biomass, richness, composition and enzymes across three soil horizons (Oe, A1 and A2) along a near‐complete fire chronosequence (1yr, 2yr, 8yr, 14yr, 30yr, 49yr and ~260yr) in cold‐temperate forests of the Greater Khingan Mountains, China. The importance of soil properties, spatial distance and tree composition were also tested. Ectomycorrhizal fungal richness and β‐glucosidase activity were strongly reduced by burning and significantly increased with time‐since‐fire in the Oe horizon but not in the mineral horizons. Time‐since‐fire and soil C/N ratio were the primary drivers of fungal composition in the Oe and A1/A2 horizons, respectively. Ectomycorrhizal fungal composition was remarkably sensitive to fire history in the Oe horizon, while saprotroph community was strongly affected by time‐since‐fire in the deeper soil horizon and this effect emerged eighteen years after fire in the A2 horizon. Our study demonstrates pronounced horizon‐dependent successional trajectories following wildfire and indicates interactive effects of time‐since‐fire, soil stoichiometry and spatial distance in the reassembly of belowground fungal communities in a cold and fire‐prone region.
... Incidence of damping-off can increase with pH in forest nursery soils (Kacprzak et al., 2001) and has been shown to cause >25% seedling losses in lodgepole pine seedlings above pH 7.0 (Griffin, 1958). Soil heating influences the composition of soil microbes and can reduce tree root symbionts after wildfire (Douglas et al., 2005;Martín-Pinto et al., 2006;Twieg et al., 2009;Glassman et al., 2016), pile burning (Pilz and Perry, 1984;Korb et al., 2004;Jiménez-Esquilín et al., 2007) and prescribed broadcast burning (Herr et al., 1994;Stendell et al., 1999;Taudière et al., 2017). However, the magnitude and duration of these effects vary with fire severity, forest types and site characteristics (Cairney and Bastias, 2007;Taudière et al., 2017). ...
... Soil heating influences the composition of soil microbes and can reduce tree root symbionts after wildfire (Douglas et al., 2005;Martín-Pinto et al., 2006;Twieg et al., 2009;Glassman et al., 2016), pile burning (Pilz and Perry, 1984;Korb et al., 2004;Jiménez-Esquilín et al., 2007) and prescribed broadcast burning (Herr et al., 1994;Stendell et al., 1999;Taudière et al., 2017). However, the magnitude and duration of these effects vary with fire severity, forest types and site characteristics (Cairney and Bastias, 2007;Taudière et al., 2017). For example, pile burning eliminated most arbuscular mycorrhizal symbionts and native plant seeds from ponderosa pine forest soils (Korb et al., 2004;Jiménez-Esquilín et al., 2007). ...
Article
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Pile burning is the most common method of logging residue disposal in Rocky Mountain forests. Though the high temperatures reached during burning affect numerous soil properties in the short term, the longer-term effects of the practice are less clear. We previously identified a 50-year time series of burn scars created after clear cut harvesting in lodgepole pine stands where we reported sparse tree colonization across the entire chronosequence. Here we analyzed soil nutrients and chemistry and conducted in situ and greenhouse seedling bioassays to determine whether edaphic factors or poor seedling performance explain the pattern. Pile burning had a lasting effect on soil pH, but nutrient availability was 2-3 times higher in burn scars compared to unburned forest soils for many constituents and planted pine seedlings had good survival and growth. However, seedling growth was slightly less in burn scars compared to unburned soils indicating suboptimal soil pH or other belowground factors may contribute to sparse tree colonization of the openings. For example, seedling survival and ectomycorrhizal fungi colonization were both lowest in the most recently created scars where soils were alkaline and improved with time as pH declined, suggesting gradual amelioration of post-fire growing conditions. Survival in burn scars was comparable for unprotected trees and those in protective mesh tubes, indicating that herbivory was not a significant impediment to seedling establishment. However, a preliminary study suggests that seed predation may have contributed to the low tree colonization into the openings. Though large burn pile scars may require soil rehabilitation, and soil changes may have a lasting effect on understory plant composition, we found that they were not a significant barrier to tree establishment in these moderate-size burn scars.
... The frequency of wildfires will also be expected to increase in this area through the association with lower than average quantity of precipitation and longer dry periods (Veble and Brečko Grubar, 2016). Drought stress may affect the structure of ECM communities or the abundance of individual taxa (Richard et al., 2011;Mrak et al., 2019) and wildfires have been reported either to cause reduction in diversity/richness of ECM fungi or have no impact, while decreased colonization of roots following wildfire by ECM fungi was confirmed by numerous studies (Taudiere et al., 2017). While Q. pubescens within this area is wellstudied, the temporal dynamics of their associated ECM fungi are not. ...
... Along with heat effects, wildfires impact carbon and nitrogen cycling and soil pH through the inputs of organic matter in the form of ash and charcoal into the soil system. Wildfires also result in the elimination of the soil organic layer and partial heat-sterilization of soil (Buscardo et al., 2010;Taudiere et al., 2017). ...
Article
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Temporal studies that would offer insight into resilience of ectomycorrhizal (ECM) communities in stress prone climates are scarce despite their role in tree nutrition and water supply. Our study characterized the vitality, community composition, diversity, and function of Quercus pubescens Willd. ECM fungi in the Sub-Mediterranean stress-prone environment for 2 consecutive years (June 2016–May 2018) and related the investigated measures to environmental parameters. ECM community was assessed for species actively associating with root tips and exploring the soil volume through the assessment of mycelial ingrowth into sand-filled mesh bags. The investigated period was characterized by a drier than average summer combined with wildfire in 2016 followed by another dry summer in 2017. The vital to non-vital ECM root tip ratio decreased below one in August 2016 and remained low until January 2018. This was ascribed to a series of stress events that occurred at the site including sequential droughts and wildfire. The most abundant ECM lineages on root tips were Tomentella and other Thelephoraceae, Sebacina, and Cenococcum while in mesh bags the most abundant were Tomentella, Sebacina, Pseudotomentella, Pyronemataceae, Inocybe, Cortinarius, Agaricales, and Boletales lineages. High intra-site variability was observed, with ECM communities directly associated with root tips and exploring the soil volume varying significantly among the plots. Community composition was stable over time, while species richness varied with mean air and soil temperature, relative air humidity, and solar radiation. The most abundant exploration type observed at this site was short distance, which was associated with precipitation along with long distance exploration type. The medium distance exploration type was temporally variable and responded to soil temperature and relative air humidity reflecting seasonality at the site. The presented results indicate complex relationships between environmental parameters, abiotic stress, and ECM fungi.
... Ectomycorrhizal (ECM) fungi are an integral part of boreal and temperate forest soils as they form symbiotic associations with trees which improves the uptake of nutrients, especially N, in exchange for photosynthetically derived carbon (C) (Leake et al., 2004;Smith and Read, 2008). Up to 75% of all plant N can be derived from ECM fungi in some terrestrial ecosystems (Hobbie and Hobbie, 2006;Nave et al., 2013). ...
... It could be that certain nutrients contained in wood ash improved EMM production, but it is also possible that the higher pH increased ECM fungal growth (Børja and Nilsen, 2009;Carrino-Kyker et al., 2016). In addition, some ECM fungal species may be adapted to forest fires allowing them to grow better in ash and even colonize ash granules or patches (Mahmood et al., 2001(Mahmood et al., , 2002Hagerberg and Wallander, 2002;Glassman et al., 2016;Taudi ere et al., 2017). ...
Article
Ectomycorrhizal (ECM) fungi are key players in N cycling in coniferous forests, and forest management such as application of wood ash can affect their functionality. The aim of this study was to determine the effects of wood ash application on ECM fungal mycelial production, capacity to retain N, diversity and community composition. In-growth mesh bags were installed in control and treated plots. After 6 months, ¹⁵N labeled ammonium and nitrate were applied into the mesh bags, and 24 h later extramatrical mycelium (EMM) was extracted and analyzed. Wood ash had no effects on EMM in-growth, N retention capacity, diversity or community composition. In contrast, there were significant seasonal differences in the amount of EMM produced. These results demonstrate that applying up to 6 t ha⁻¹ of wood ash in this type of plantation forest is a safe management practice that does not increase N leaching or negatively affect ECM fungi.
... However, how the variability in fire severity affects different taxa and larger ecological assemblages during the post-fire years has remained poorly studied (e.g. Taudiere et al., 2017;Pressler et al., 2019). ...
Article
Saprotrophic macrofungi are key decomposers of plant biomass in forests. These fungi form ecologically diverse group where different species specialize in specific substrates. Wildfires produce massive amounts of heterogeneous dead substrates. The postfire succession of saprotrophic fungi on these substrates may have major consequences on how carbon and nutrients are released back to forest ecosystems after a fire. We studied the effects of a wildfire (covering 143 ha) on saptroptrophic macrofungi (Basidiomycota and Ascomycota) in a Scots pine (Pinus sylvestris) dominated forest in eastern Finland during 12 years after the wildfire. In particular, we focused on the consequences that within-fire variation in fire severity had on fungal assemblages. Twenty-two permanent sample plots (10 × 10 m2 each) were monitored annually. Plots were located on sites with four different fire severity classes and on two unburned control sites. A total of 43 102 sporocarps of macrofungi were collected. Based on fungal life histories, we separated four different groups in the analyses: (1) wood-associated fungi on decayed wood, (2) decomposers of organic matter in soil or that live on bare mineral soil in forest floor, (3) biotrophic macrofungi that are associations between algae and fungi and that may also be symbiotic with mycorrhizae fungi, and (4) parasites on a living host plant or other fungi. In total, 219 species were observed. Fire severity affected species richness and composition, and fire always increased fungal diversity in comparison with unburned control sites. On the burned sites, species richness was highest on sites of medium burn severity (114 species in total, vs. 88–106 spp. on other burned sites). Substrate association of species was closely connected to assemblage dynamics: on soil and humus substrates, the succession of fire-associated pyrophilous species was rapid when compared to the succession of aphyllophoroid wood-associated macrofungi (AWAM). Pyrophilous and AWAM assemblages comprised many indicator species that occurred only ephemerally during the few years after the fire. In previous studies, AWAM assemblages often respond negatively to forest fires in short-term. Our results, however, show that if also other than AWAM macrofungi are included, there are several species typical for immediate post-fire habitats. The role that these species have on forest ecosystem and – for example – on carbon dynamics after a wildfire remains an important topic for future studies. From the conservation viewpoint, the finding emphasizes that post-fire young successional forests are important habitats for specialized and rare fungi.
... Castaño et al. (2018a) evaluated the effects of forest thinning on soil fungal communities and found fungal community changes driven by inter-annual variation of environmental factors, rather than by the forestry practices. The potential exoenzymatic activities of ectomycorrhizal communities change after tree clear-cutting (Kohout et al. 2018) but potential functional complementarity and redundancy may still support growth of the regenerated seedlings (Jones et al. 2010;Walker et al. 2016 Taudière et al. 2017). Natural re-establishment of ectomycorrhizal fungi after clear-cutting can be achieved by means of mycelium, sclerotia (vegetative resistance structures formed by a few ectomycorrhizal species) and spores (Brundrett 1991). ...
Article
Forest management aimed to maximize timber production might impact soil fungi, especially those symbioti-cally associated to tree roots. In this study, we analyse the temporal dynamics of soil fungi along five sampling years after tree removal in a managed Pinus sylvestris stand in northern Spain, where timber production is combined with regular mushroom harvesting. Two management methods were tested: total and partial clear-cutting leaving retention trees for seedling regeneration. Undisturbed, uncut plots were also included in the experiment as a control treatment. The whole fungal community (phylotypes and ecological guilds) were analysed by high-throughput Illumina MiSeq sequencing of fungal ITS1 amplicons. We hypothesized that (1) ec-tomycorrhizal fungal communities will decrease after both clear-cutting treatments with a concurrent increase in the abundance of saprotrophs, (2) the abundance and diversity of the ectomycorrhizal guild will be more preserved in partially clear-cut than in total clear-cut plots, and (3) the overall fungal diversity will decrease in the cut plots leading to major losses of ectomycorrhizal species. Our results show that soil fungal composition changed across the five years after clear-cutting by decreasing ectomycorrhizal fungi and increasing saprotrophs. However, these changes did not significantly affect fungal diversity and there were taxa-specific responses to tree harvest treatments. Boletus edulis, the most abundant ectomycorrhizal species fruiting in the study area and a valuable local non-forest resource, was negatively affected by either clear-cutting treatments. Soil fungal community composition in partially clear-cut areas was not different from that of total clear-cut areas. Our results indicate a strong effect of tree harvest on the relative abundance of ectomycorrhizal fungi along the first years after clear-cutting. However, levels of fungal diversity were comparable to the undisturbed forest, thus suggesting a potential further recovery of ectomycorrhizal fungi through the colonization of the regenerated seedlings.
... One of the main limiting factors of plant growth in the Mediterranean environment is summer drought, so relative research on the ecophysiological (and especially hydric) effects of ECMs on Mediterranean hosts has been important, but remains still scarce; in fact, most international studies have focused on dry temperate forests (British Columbia and Spain) and Mediterranean forests (Spain and California) (Schoonmaker et al. 2007;Querejeta et al. 2007;Dominguez-Núñez et al. 2006;Morte et al. 2010). Both water availability and fire (Taudière et al. 2017;Vasquez-Gassibe et al. 2014;Martín-Pinto et al. 2006) remain key factors in the interaction of Mediterranean ECM fungi with their hosts and habitats. ...
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In the current context in which mycological resources have acquired a strong socio-economic interest, forest mycological management is necessary, with objectives of ecological sustainability in their use and conservation. The key implication of soil fungi in forest biogeochemical processes and the new knowledge on ectomycorrhizal networks and edaphic microbial ecology, make it necessary to rethink traditional silviculture and to study its effects on forest fungal communities. In the Mediterranean region, the current prospects of climate change seem to increase the stress on forest soils and forest life, already affected by poor management and commercial overexploitation of mushrooms, among other causes. We review in this chapter the literature on silvicultural practices that have positively or negatively affected soil fungal diversity and yield, focusing especially on experiences in the Mediterranean forest. We briefly analyze the potential of mycorrhizal applications and the knowledge of ectomycorrhizal networks for their application in forest management. The application of retention silviculture practices, retaining trees, tree patches or understory during forest harvesting can help to preserve ectomycorrhizal networks, buffering the disturbances generated by silvicultural treatments.
... overstory mortality, high consumption of organic soils and downed woody debris), below-ground biological change is rarely measured, but fire effects are often deemed severe if soil temperatures exceed specified thermal intensity benchmarks (Busse et al., 2005;Hartford and Frandsen, 1992;Monsanto and Agee, 2008). Empirical studies of soil biota document a wide range of positive, neutral, and negative responses to wildland fire for many different organisms (Cairney and Bastias, 2007;Dove and Hart, 2017;Hart et al., 2005;Kobziar and Stephens, 2006;Taudière et al., 2017;Wang et al., 2012), yet both the scientific and management communities commonly focus on a select group of soil temperatures to pinpoint thresholds where significant biotic repercussions from fire are to be expected (Busse et al., 2014(Busse et al., , 2005Hungerford et al., 1991;Preisler, et al., 2000). ...
Article
Soil heating caused by prescribed or wildland fire commonly focuses on a single biological thermal threshold of 60 °C for the duration of one minute to represent organism death. This metric severely misrepresents the heterogeneity of the soil environment, the physiological attributes and tolerances of organisms, and the complexity of heat transfer through soils. Measurements of biotic death in simulated laboratory experiments render research findings difficult to extrapolate to forest and grassland soils. The disparity between assumed biological responses and the diversity of biological responses after wildland fire events calls for a thorough review of soil biological heating thresholds. In this review, we synthesize and compare research that directly relates soil heating temperature and duration to biological responses, provide relevant models for temperature-duration responses of soil organisms in lieu of a strict threshold, and recommend applications of soil heating data for wildland fire and ecosystem management. For no single study or group of organisms was a threshold of 60 °C for one-minute duration evidenced. All soil organisms reviewed, which included roots, mesofauna, bacteria, fungi, microbial biomass, and soil respiration, displayed both positive and negative responses to soil heating across temperature and duration gradients. We, therefore, discourage the use of the traditionally accepted metric of 60 °C for the duration of one minute. Instead, we present models of duration-temperature relationships of soil biota and invite interdisciplinary efforts from researchers and managers to directly measure biological responses on a case-by-case basis.
... Long-term smoldering combustion can conduct heat through soil, leading to lethal temperatures that kill roots and mycorrhizae. This impact decreases water transport and nutrient acquisition in the shortterm and results in NSC drains to rebuild lost roots (Varner et al 2009, O'Brien et al 2010, Taudière et al 2017. Fire-caused tree mortality from root death alone is likely uncommon, as mineral soil is a poor conductor of heat and forest floor organic layers Figure 2. Fire-caused tree mortality results from injuries to the crown, bole, and roots. ...
Article
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Each year wildland fires kill and injure trees on millions of forested hectares globally, affecting plant and animal biodiversity, carbon storage, hydrologic processes, and ecosystem services. The underlying mechanisms of fire-caused tree mortality remain poorly understood, however, limiting the ability to accurately predict mortality and develop robust modeling applications, especially under novel future climates. Virtually all post-fire tree mortality prediction systems are based on the same underlying empirical model described in Ryan and Reinhardt (1988 Can. J. For. Res. 18 1291–7), which was developed from a limited number of species, stretching model assumptions beyond intended limits. We review the current understanding of the mechanisms of fire-induced tree mortality, provide recommended standardized terminology, describe model applications and limitations, and conclude with key knowledge gaps and future directions for research. We suggest a two-pronged approach to future research: (1) continued improvements and evaluations of empirical models to quantify uncertainty and incorporate new regions and species and (2) acceleration of basic, physiological research on the proximate and ultimate causes of fire-induced tree mortality to incorporate processes of tree death into models. Advances in both empirical and process fire-induced tree modeling will allow creation of hybrid models that could advance understanding of how fire injures and kills trees, while improving prediction accuracy of fire-driven feedbacks on ecosystems and landscapes, particularly under novel future conditions.
... Moreover, even low severity prescribed burning could have negative longlasting impacts on the ectomycorrhizal community (Taudi ere et al. 2017). However, currently only a limited number of studies have assessed fire effects on mycorrhizae, hindering synthesis at the time of writing, but available evidence indicates a negative effect of elevated fire recurrence (Taudi ere et al. 2017, Tomao et al. 2017. ...
... Long-term smoldering combustion can conduct heat through soil, leading to lethal heat levels that injure and kill roots and mycorrhizae. This impact decreases water transport and nutrient acquisition in the short-term and results in nonstructural carbohydrate drains to rebuild lost roots over longer periods (O'Brien et al. 2010;Taudière et al. 2017;Varner et al. 2009). Fire-caused tree mortality from root death alone is uncommon, as mineral soil is a poor conductor of heat and forest floor organic soils insulate underlying mineral soil and roots from flames (Hartford and Frandsen 1992). ...
Chapter
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This chapter provides a overview of direct and indirect causes of tree mortality from fire, describes resprouting vs. top-kill responses, and applications that predict post-fire tree mortality.
... Moreover, even low severity prescribed burning could have negative longlasting impacts on the ectomycorrhizal community (Taudi ere et al. 2017). However, currently only a limited number of studies have assessed fire effects on mycorrhizae, hindering synthesis at the time of writing, but available evidence indicates a negative effect of elevated fire recurrence (Taudi ere et al. 2017, Tomao et al. 2017. ...
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Over the past 15 years, 3 million hectares of forests have been converted into shrublands or grasslands in the Mediterranean countries of the European Union. Fire and drought are the main drivers underlying this deforestation. Here we present a conceptual framework for the process of fire-induced deforestation based on the interactive effects of fire and drought across three hierarchical scales: resistance in individuals, resilience in populations, and transitions to a new state. At the individual plant level, we review the traits that confer structural and physiological resistance, as well as allow for resprouting capacity: deforestation can be initiated when established individuals succumb to fire. After individuals perish, the second step toward deforestation requires a limited resilience from the population, that is, a reduced ability of that species to regenerate after fire. If individuals die after fire and the population fails to recover, then a transition to a new state will occur. We document trade-offs between drought survival and fire survival, as embolism resistance is negatively correlated with fire tolerance in conifers and leaf shedding or drought deciduousness, a process that decreases water consumption at the peak of the dry season, temporally increases crown flammability. Propagule availability and establishment control resilience after mortality, but different hypotheses make contrasting predictions on the drivers of post-fire establishment. Mycorrhizae play an additional role in modulating the response by favoring recovery through amelioration of the nutritional and water status of resprouts and new germinants. So far, resprouter species such as oaks have provided a buffer against deforestation in forests dominated by obligate seeder trees, when present in high enough density in the understory. While diversifying stands with resprouters is often reported as advantageous for building resilience, important knowledge gaps exist on how floristic composition interacts with stand flammability and on the "resprouter exhaustion syndrome," a condition where pre-fire drought stress, or short fire return intervals, seriously restrict post-fire resprouting. Additional attention should be paid to the onset of novel fire environments in previously fire-free environments, such as high altitude forests, and management actions need to accommodate this complexity to sustain Mediterranean forests under a changing climate.
... Moreover, even low severity prescribed burning could have negative longlasting impacts on the ectomycorrhizal community (Taudi ere et al. 2017). However, currently only a limited number of studies have assessed fire effects on mycorrhizae, hindering synthesis at the time of writing, but available evidence indicates a negative effect of elevated fire recurrence (Taudi ere et al. 2017, Tomao et al. 2017. ...
Article
Full-text available
Over the past 15 years, 3 million hectares of forests have been converted into shrublands or grasslands in the Mediterranean countries of the European Union. Fire and drought are the main drivers underlying this deforestation. Here we present a conceptual framework for the process of fire-induced deforestation based on the interactive effects of fire and drought across three hierarchical scales: resistance in individuals, resilience in populations, and transitions to a new state. At the individual plant level, we review the traits that confer structural and physiological resistance, as well as allow for resprouting capacity: deforestation can be initiated when established individuals succumb to fire. After individuals perish, the second step toward deforestation requires a limited resilience from the population, that is, a reduced ability of that species to regenerate after fire. If individuals die after fire and the population fails to recover, then a transition to a new state will occur. We document trade-offs between drought survival and fire survival, as embolism resistance is negatively correlated with fire tolerance in conifers and leaf shedding or drought deciduousness, a process that decreases water consumption at the peak of the dry season, temporally increases crown flammability. Propagule availability and establishment control resilience after mortality, but different hypotheses make contrasting predictions on the drivers of post-fire establishment. Mycorrhizae play an additional role in modulating the response by favoring recovery through amelioration of the nutritional and water status of resprouts and new germinants. So far, resprouter species such as oaks have provided a buffer against deforestation in forests dominated by obligate seeder trees, when present in high enough density in the understory. While diversifying stands with resprouters is often reported as advantageous for building resilience, important knowledge gaps exist on how floristic composition interacts with stand flammability and on the “resprouter exhaustion syndrome,” a condition where pre-fire drought stress, or short fire return intervals, seriously restrict post-fire resprouting. Additional attention should be paid to the onset of novel fire environments in previously fire-free environments, such as high altitude forests, and management actions need to accommodate this complexity to sustain Mediterranean forests under a changing climate.
... Early seedling establishment is facilitated by mycorrhizae (Baar, Horton, Kretzer, & Bruns, 1999;Horton, Bruns, & Parker, 1999;Nuñez, Horton, & Simberloff, 2009). Fire alters the species composition of ectomycorrhizae, although how fire affects mycorrhizal species richness and diversity, and the resultant impacts on recruitment remain unclear (Taudière, Richard, & Carcaillet, 2017). Herbivory following fire can be high enough to limit regeneration (Bartos, Brown, & Booth, 1994) and has the potential to alter postfire vegetation trajectories (Mills, 1983). ...
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1.Climate change indirectly affects forest ecosystems through changes in the frequency, size, and/or severity of wildfires. In addition to its direct effects prior to fire, climate also influences immediate post‐fire recruitment, with consequences for future vegetation structure and fire activity. A major uncertainty, therefore, is if, when and where vegetation shifts will occur. 2.With an emphasis on species traits, we use a demographic framework to examine how the interaction of changing climate and fire will affect post‐fire woody vegetation recruitment and the likelihood of vegetation shifts. Each demographic stage – adult mortality, propagule availability, seed germination, seedling establishment, and seedling survival – serves as a filter through which a species must pass for establishment and recovery to occur. 3.We apply this framework to case studies in western North American forests, including boreal and southwestern U.S. Pinus ponderosa forests, to help understand the mechanisms behind recent post‐fire vegetation changes. The case studies highlight how changes in climate and fire properties will make it increasingly difficult for some species to pass through each demographic filter in the future. 4.As climate warming continues, we expect increased dominance of species that resprout following fire, maintain canopy or soil seedbanks, have long distance seed dispersal, produce drought‐tolerant seedlings, and/or reach reproductive maturity quickly. The persistence of post‐fire vegetation shifts will depend the on ratio of recovery time to disturbance interval(s). 5.An advantage of the demographic‐filter framework is that it places emphasis on mechanisms, thus improving our ability to anticipate future vegetation shifts. As such, it highlights the clear need for more mechanistic studies of post‐fire recruitment to disentangle the relative effects of multiple drivers in post‐fire environments. This article is protected by copyright. All rights reserved.
... bryophytes, fungi, lichens, arthropods, or small vertebrates) could provide informative complementary perspectives on Mediterranean ecosystems (e.g. Jacquet and Prodon 2009;Taudière et al. 2017b;Perez-Valera et al. 2018;Hinojosa et al. 2019;Lazarina et al. 2019). ...
Article
Post-fire vegetation dynamics is examined over an extended timescale, to investigate the long-term effects of fire on plant diversity and to verify if a succession model, such as Clements’ “relay floristic” or Egler's “initial floristic” models, applies to post-fire dynamics in Mediterranean communities. In the Alpilles massif, Provence, southern France, 20 plots were sampled at each of six sites; five that had been burned by wildfires within the last 30 years (1977, 1983, 1989, 1999 and 2003), and a control site not burned for at least 80 years. Temporal variations in relative species density are modelled by regression curves. The structure of diversity is analysed based on mean species richness (α), beta diversity (βw), Shannon diversity index (H) and relative equitability index (Eh), knowing that the Egler's model leads to the prediction that richness should be highest immediately following disturbance. No significant differences in species richness were detected between sites, and species diversity is not related to time since the last fire except 2 years after fire that shows the highest βw-diversity resulting from an elevated list of species per site (γ-diversity) immediately after fire. Instead, an effect of site location on species diversity is detected. The observed post-fire dynamics show a progressive transition between three stages, from initial, through transitional to mature. Each stage is characterized by different relative species density. Furthermore, several plant species can be considered as early, intermediate or late successional species with regards to their density at different times after burning. In conclusion, initial floristic composition model (Egler's model) applies to this ecosystem, with all species present at the early post-fire dynamics, and the diversity shows the highest γ-diversity 2 years after fire. In the long term (>50 years), a successional pathway can be discerned. The growth rates and longevity of main species influence the post-fire dynamics.
... In contrast to rapid colonization by the post-fire fungi, recovery of soil fungal communities to pre-fire condition may take more than ten years (Dooley and Treseder, 2012;Oliver et al., 2015;Hart et al., 2018). Taudière et al. (2017) have reviewed the main studies on the effect of fire on ectomycorrhizal species and have concluded that prescribed burning has a negative effect on the aboveground ectomycorrhizal fungal richness (i.e. reproductive structures). ...
Article
The influence of forest management on fungal diversity and community composition has been the subject of a wide number of studies over the last two decades. However, the difficulty of studying the complex kingdom of fungi under real forest conditions has led to rather scattered scientific knowledge. Here, we provide the current state of knowledge suggesting future research directions regarding (i) stand structure attributes (age, tree cover, stand density, tree species composition), (ii) management history (managed vs unmanaged), (iii) silvicultural treatments (thinning, clearcutting, shelterwood methods, selective cutting) and (iv) other anthropogenic disturbances (mushroom picking, salvage logging, prescribed burning, fertilization) affecting fungal diversity and community composition. The reviewed studies reported a positive correlation between fungal diversity and stand structure variables such as canopy cover, basal area of the stand and tree species diversity, particularly for mycorrhizal species. Abundance and diversity in size, tree species and decomposition stage of deadwood are reported as positively related to richness of wood-inhabiting fungi. The main findings about the effects of silvicultural practices suggest that the higher is the management intensity the lower is the diversity of ectomycorrhizal and wood-inhabiting species, at least in the short term. We have therefore reported those silvicultural practices which may reduce trade-offs between timber harvesting and fungal diversity conservation. Indeed, fungal diversity can be conserved in managed forests if (i) low impact logging operations are performed; (ii) stand structural complexity and late-successional forest characteristics are enhanced; (iii) deadwood amount and diversity is promoted, (iv) landscape heterogeneity and connectivity is improved or maintained.
... Generally, a disturbance, such as fire, has negative effects on ECM fungi; however, this does not apply to all types of fire Salo and Kouki, 2018). In this study, ECM fungal richness did not differ significantly between treatments, possibly because the heat generated by the prescribed burning was not high enough (Espinosa et al., 2018; to cause change (Dahlberg et al., 2001;Taudière et al., 2017). Hence, mycorrhizal fungi in the soil may have been able to escape the penetrating heat being associated with forests that have been affected by burning for generations (Dahlberg et al., 2001). ...
Article
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In the context of global change, wildfires are not only a threat but are also increasing in their severity in forest ecosystems worldwide, affecting and modifying vegetation, wildlife, and fungal dynamics. Mediterranean ecosystems are frequently affected by fire and prescribed burning is being increasingly used as a tool to reduce the risk and severity of wildfires. Although some of the effects of prescribed burning have been studied, the best moment to perform a prescribed burn to reduce the impact of fire on fungal communities has not been fully investigated. In this study, we analysed the effect of prescribed burning in two different seasons (spring and autumn) on soil fungi associated with natural Pinus nigra forests. Four years after prescribed burning was applied, our analyses showed that the total fungal richness and the composition of fungal communities in spring-burned, autumn-burned, and unburned control plots did not differ significantly. However, analyses of specific phyla and functional trophic groups did reveal some significant differences between spring- or autumn-burned plots and unburned control plots. Valuable edible fungi, which were not affected by the prescribed burning, were also found in the study area. Thus, our results suggest that prescribed burning is not only an interesting tool that could be used to reduce the risk of wildfire but also is compatible with the conservation of fungal communities, and could even promote specific valuable edible species, generating complementary incomes for the rural population. Although further studies are needed, our analyses suggest that the season (spring or autumn) in which prescribed burning is performed does not affect fungal conservation and, therefore, does not need to be one of the factors taken into consideration when selecting the most appropriate time to perform a prescribed burning.
... bryophytes, fungi, lichens, arthropods, or small vertebrates) could provide informative complementary perspectives on Mediterranean ecosystems (e.g. Jacquet and Prodon 2009;Taudière et al. 2017b;Perez-Valera et al. 2018;Hinojosa et al. 2019;Lazarina et al. 2019). ...
Article
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Changes in community diversity and dynamics after fires in Mediterranean ecosystems are rarely investigated more than a few years after the fire even though pronounced changes can be expected in the longer term due to substitution of canopy species. Pinus halepensis is strongly promoted by wildfire and should therefore be gradually substituted by Quercus species as the time since the last fire increases. We hypothesized that this tree substitution would cause changes in understorey plant diversity by changing resource availability and the abundance and properties of woody debris, leading to changes in biogeochemical processes. To test this hypothesis, we investigated the effect of the time since last fire on vascular plant composition and diversity by studying a 130 years post-fire chronosequence in mixed Mediterranean forests. The canopy composition went from domination by Pinus halepensis to domination by Quercus 70 years after the most recent fire. This transformation was associated with a change in the understorey involving a rarefaction of species present during the first decades after the fire. The plant density or cover also changed with time since the last fire, indicating a succession driven by species rarefaction rather than substitution. The mean richness and Shannon diversity per quadrat were highest shortly after the fire, and were significantly lower 70 or more years after the last fire. Fires are important for supporting highly diversified fire-dependent plant communities, and total plant richness decreases monotonically over time after fires, suggesting that fire suppression may reduce diversity in Mediterranean forests.
... Studies reporting pyrophilous fungi have largely focused on boreal forests (Dahlberg et al. 2001;de Groot et al. 2013;Sun et al. 2015), western North American coniferous forests (Bruns et al. 2002(Bruns et al. , 2005Westerling et al. 2006;Sun et al. 2015;Reazin et al. 2016), the Mediterranean (Buscardo et al. 2010), and Australia (McMullan-Fisher et al. 2002. Taudière et al. (2017) summarized studies involving both wildfires and prescribed burns and their effects on ectomycorrhizal (ECM) fungi worldwide, but missing from all these studies are data for pyrophilous fungi in eastern North America. The reason for this lack of coverage may be that fire prevention strategies in eastern North American temperate forests have successfully suppressed forest fires for approximately 100 y (Nowacki and Abrams 2008;Aldrich et al. 2010;Flatley et al. 2011Flatley et al. , 2013Lafon et al. 2017). ...
Article
Following a late fall wildfire in 2016 in the Great Smoky Mountains National Park, pyrophilous fungi in burn zones were documented over a 2-y period with respect to burn severity and phenology. Nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) barcodes were obtained to confirm morphological evaluations. Forty-one taxa of Ascomycota and Basidiomycota were identified from burn sites and categorized as fruiting only in response to fire or fruiting enhanced by fire. Twenty-two species of Pezizales (Ascomycota) were among the earliest to form ascomata in severe burn zones, only one of which had previously been documented in the Great Smoky Mountains National Park. Nineteen species of Basidiomycota, primarily Agaricales, were also documented. Among these, only five species (Coprinellus angulatus, Gymnopilus decipiens, Lyophyllum anthracophilum, Pholiota carbonicola, and Psathyrella pennata) were considered to be obligate pyrophilous taxa, but fruiting of two additional taxa (Hygrocybe conica and Mycena galericulata) was clearly enhanced by fire. Laccaria trichodermophora was an early colonizer of severe burn sites and persisted through the winter of 2017 and into spring and summer of 2018, often appearing in close association with Pinus pungens seedlings. Fruiting of pyrophilous fungi peaked 4–6 mo post fire then diminished, but some continued to fruit up to 2.5 y after the fire. In all, a total of 27 previously unrecorded taxa were added to the All Taxa Biodiversity Inventory (ATBI) database (~0.9%). Most pyrophilous fungi identified in this study are either cosmopolitan or have a Northern Hemisphere distribution, but cryptic endemic lineages were detected in Anthracobia and Sphaerosporella. One new combination, Hygrocybe spadicea var. spadicea f. odora, is proposed.
... Is there any key microbial group helping the process of recovery after fire? Although researchers have conducted some preliminary studies on soil microbial communities after fire (Mataix-Solera et al. 2009;Taudière et al. 2017;Catalanotti et al. 2018), these questions have not yet to be well answered. In this study, NTF collected from two different soil depths (0-10 and 10-20 cm) in two different burned sites and corresponding unburned sites (CS sites and YL sites) were analyzed. ...
Article
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Soil microbes’ response to sudden environmental changes is very complicated and has been lively debated. There are a handful of questions yet to answer: are there any succession rules for different soil microbial species to fit in the suddenly changed environment? And what is the correlation between the community succession and the habitat recovery? These questions remain unanswered yet. Nematode-trapping fungi (NTF) play a very important role in the soil ecosystem and can be studied by traditional culture method easily. So, in this study, the NTF community in two burned sites at two depths (0–10 and 10–20 cm) was investigated in comparison with adjacent unburned sites. While the original NTF community structure was rather different in the two unburned sites, the NTF community presented a consistent pattern in the two burned sites: (1) considerable amount of NTF in the shallow soil (0–10 cm) was killed by the extremely high temperature of fire and the vacant niches were subsequently replaced with NTF communities that were originally distributed in the deep soil (10–20 cm); (2) dominant species in the community changed from Arthrobotrys fungi which showed stronger saprophytic ability to Dactylellina fungi which showed stronger capturing ability; and (3) the vacant niche caused by the movement of Dactylellina fungi was taken by Drechslerella fungi. The study shows that microbes inhabited in the deep soil played a critical role in the after-fire process to recovery of the soil ecological system.
... Both arbuscular (AM) and ectomycorrhizal (EM) fungi provide plant hosts with nutrients (mainly P and N respectively) in return for carbon. Both groups also display seasonal peaks in abundance (Harvey, Jurgensen and Larsen 1978;Santos-Gonzalez, Finlay and Tehler 2007), and are strongly impacted by fire (Klopatek, Debano and Klopatek 1988;Dhillion and Anderson 1993;Taudière, Richard and Carcaillet 2017). Fire is well known to decrease the richness and in situ colonization of AM and EM fungal communities (Dove and Hart 2017). ...
Article
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Fire alters microbial community composition, and is expected to increase in frequency due to climate change. Testing whether microbes in different ecosystems will respond similarly to increased fire disturbance is difficult though, because fires are often unpredictable and hard to manage. Fire recurrent or pyrophilic ecosystems, however, may be useful models for testing the effects of frequent disturbance on microbes. We hypothesized that across pyrophilic ecosystems, fire would drive similar alterations to fungal communities including altering seasonal community dynamics. We tested fire's effects on fungal communities in two pyrophilic ecosystems, a Longleaf pine savanna and tallgrass prairie. Fire caused similar fungal community shifts including a) driving immediate changes that favored taxa able to survive fire and take advantage of post-fire environments, and b) altering seasonal trajectories due to fire-associated changes to soil nutrient availability. This suggests that fire has predictable effects on fungal community structure and intra-annual community dynamics in pyrophilic ecosystems, and that these changes could significantly alter fungal function. Parallel fire responses in these key microbes may also suggest that recurrent fires drive convergent changes across ecosystems, including less fire frequented systems that may start burning more often.
... Relative to proximate areas without a recent history of fire, burned areas in the Madrean Sky Island ranges have EM fungal communities that remain distinct ca. 12e16 years after wildfire, as observed in other regions (e.g, see Glassman et al., 2016;Taudi ere et al., 2017). As fire intervals grow shorter and fires become more widespread and intense, the potential for local recolonization from unburned patches likely will decrease in these isolated forests, such that the potential for species loss from isolated Sky Island ranges appears to be high. ...
Article
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With a warming and drying climate, coniferous forests worldwide are increasingly threatened by wildfires. We examined how fire impacts ectomycorrhizal (EM) fungi associated with Pinus ponderosa, an important tree species in western North America. In the biodiverse Madrean Sky Islands, P. ponderosa forests exist on insular mountains separated by arid lands. How do EM fungi in these isolated ranges respond to fire, and can data from individual ranges predict community shifts after fire at a regional scale? By comparing areas in two ranges that experienced moderate fires 12–16 y earlier, and proximate areas in each range without recent fire, we reveal pervasive effects on diversity and composition of EM communities more than a decade after moderate fires occurred. Post-fire differences in EM communities in different ranges highlight the challenge of predicting fungal community shifts in these isolated forests, despite similarities of climate, plant communities, and fire severity.
... The most recent papers are listed first. Shaded cells indicate whether each paper contained discussion (Discuss) or data-based inferences (Data) concerning fire attributes (References not cited in the article main text but included in the literature review and in Additional file 1 are: Abella and Springer 2015;Adams et al. 2013;Bentley and Penman 2017;Beringer et al. 2015;Brose 2014;Brown et al. 2016;Campbell 2012;Cannon et al. 2017;Cawson et al. 2012;Contreras et al. 2011;Darracq et al. 2016;Dey and Schweitzer 2018;Driscoll et al. 2010a;Driscoll et al. 2010b;Engstrom 2010;Fernandes 2013;Freeman et al. 2017;Frelich et al. 2017;Fulé et al. 2012;Geiser et al. 2018;Hessburg et al. 2015;Hesseln 2018;Hunt et al. 2014;Hutchen et al. 2017;McIver et al. 2013;Meador et al. 2017;Miesel et al. 2012;Page et al. 2014;Parkins et al. 2017;Prichard et al. 2017;Ratajczak et al. 2014;Robinson et al. 2013;Slapcinsky et al. 2010;Taudiére et al. 2017). ...
Article
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The idea that not all fire regimes are created equal is a central theme in fire research and conservation. Fire frequency ( i.e., temporal scale) is likely the most studied fire regime attribute as it relates to conservation of fire-adapted ecosystems. Generally, research converges on fire frequency as the primary filter in plant community assembly and structure, which is often critical to conservation goals. Thus, conservation success is commonly linked to fire frequency in fire regimes. The spatial scale of fire may also be vital to conservation outcomes, but this attribute is underrepresented in the primary literature. In our global, contemporary literature search, we found 37 published syntheses concerning the effects of prescribed fire in conservation over the last decade. In those syntheses, only 16% included studies that reported data-based inferences related to the spatial scale of the fire, whereas 73% included discussion of empirical studies on the temporal scale. Only one of the syntheses discussed studies that explicitly tested the effects of spatial extent, and none of those studies were experiments manipulating spatial scale. Further, understanding spatial-scale-dependent patterns may be relevant because two databases of fire-occurrence data from the United States indicated that spatial scale among lightning-ignited and prescribed fires may have been mismatched over the past few decades. Based on a rich ecological literature base that demonstrates pervasive scale-dependent effects in ecology, spatial-scale-dependent relationships among prescribed fire regimes and conservation outcomes are likely. Using examples from the southeastern United States, we explored the potential for scale-dependent ecological effects of fire. In particular, we highlighted the potential for spatial scale to (a) influence wildlife populations by manipulating the dispersion of habitat components, and (b) modulate plant community assembly and structure by affecting seed dispersal mechanics and spatial patterns in herbivory. Because spatial-scale-dependent outcomes are understudied but likely occurring, we encourage researchers to address the ecological effects of spatial scale in prescribed-fire regimes using comparative and manipulative approaches.
... Moreover, saprobic fungi co-inhabit the rhizosphere with EcM fungi; playing key roles in decomposition (Smith & Read, 2009), soil moisture retention (Egger and Paden, 1986), and are vital for the formation, stabilization, and disintegration of soil aggregates (Lehmann and Rillig, 2015;Ritz and Young, 2004;Tisdall et al., 2012). Wildfire can directly alter the soil microbial community through selective heat-induced mortality (DeBano et al., 1998), resulting in negative to neutral effects (Taudière et al., 2017). In addition, wildfire leads to indirect long-term effects via host mortality (Buscardo et al., 2011;Pec et al., 2017;Sun et al., 2015), shifts in plant dominance (Ning et al., 2021), and litter input and structure (Bhatnagar et al., 2018;Ficken and Wright, 2017). ...
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... Fire typically reduces the microbial biomass in soil, and the fungal portion is particularly sensitive to burning (Guerrero et al., 2005;O'Dea, 2007;Dooley and Treseder, 2011;Holden and Treseder, 2013;Pressler et al., 2019). Fire has the potential to negatively impact pre-existing ectomycorrhizal communities and subsequent colonization of regenerating seedlings (Cairney and Bastias, 2007;Mataix-Solera et al., 2009;Dove and Hart, 2017;Taudière et al., 2017). Soil saprophytes also can be decimated (Widden and Parkinson, 1975), but these fungi appear less susceptible and may recover faster after fire (Treseder et al., 2004;Sun et al., 2015;Holden et al., 2016). ...
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Presentation at the 9th International Conference on Mycorrhiza (ICOM) in Prague (session ”Advances in conservation through a better understanding of mycorrhizal ecology”)
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Chapter
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Wildfire is a major disturbance factor in boreal forests where it is important in rejuvenating soil properties and encouraging tree regeneration and growth. However, the mechanisms behind these effects are poorly understood and little is known as to the ecological effects of charcoal produced by wildfire in these ecosystem. In this study we firstly quantified the mass of charcoal in a chronosequence of twelve forest sites in northern Sweden and found charcoal mass in soil to vary from 984 to 2074 kg ha-1; these levels appear to be sufficient for charcoal to have important ecological effect through its sorptive abilities. We then investigated the ability of charcoal from 32 forest stands (representing a range of ages from 1 to 350 yr since last fire) to adsorb phenolic compounds produced by the late successional dwarf shrub Empetrum hermaphroditum; phenolic compounds from this species have previously been shown to have important phytotoxic effects in boreal forests. Charcoal in soil from forests younger than 100 yr was very effective at reducing these effects while older charcoal was not, suggesting that the sorptive ability is likely to be most important in earlier-successional forests. Experimental reheating of deactivated older charcoal from soil showed that temperatures above 450°C could reactivate charcoal. A microcosm experiment also revealed that soil microbes could effectively reactivate young charcoal that had been saturated with phenolics. Finally we investigated the effects of artificially made charcoal on soil microbial properties at six sites. The microbial biomass was consistently enhanced in humus when it was placed adjacent to charcoal particles. Decomposition of plant litter was sometimes also affected by being in the proximity of charcoal but the direction of these effects was unpredictable. We conclude that charcoal might catalyse important ecological soil processes in early-successional boreal forests, effects that diminish as succession proceeds, and ultimately may have important long-term consequences for stand productivity and ecosystem function, especially in forests under strict fire control.
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Fungi play an important role in plant communities and ecosystem function. As a result, variation in fungal community composition can have important consequences for plant fitness. However, there are relatively few empirical data on how dispersal might affect fungal communities and the ecological processes they mediate. We established sampling stations across a large area of coastal landscape varying in their spatial proximity to each other and contrasting vegetation types. We measured dispersal of spores from a key group of fungi, the Basidomycota, across this landscape using qPCR and 454 pyrosequencing. We also measured the colonization of ectomycorrhizal fungi at each station using sterile bait seedlings. We found a high degree of spatial and temporal variability in the composition of Basidiomycota spores. This variability was in part stochastic and in part explained by spatial proximity to other vegetation types and time of year. Variation in spore community also affected colonization by ectomycorrhizal fungi and seedling growth. Our results demonstrate that fungal host and habitat specificity coupled with dispersal limitation can lead to local variation in fungal community structure and plant-fungal interactions. Understanding fungal communities also requires explicit knowledge of landscape context in addition to local environmental conditions.
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Reviews the discipline of fire ecology under the following chapter headings: introduction (global importance, methods, ecological concepts); why and how do ecosystems burn (the fire regime, prerequisites for fire, temperatures of fires and survival of plant tissue); surviving fires - vegetative and reproductive responses; plant demography and fire interval-dependent effects (types of population growth, modelling population growth, demography and the fire interval hypothesis, density dependence and population regulation - the self-reegulatory hypothesis) and event-dependent effects (effects of fire intensity and season on survival and recruitment, effects of ground fires and fire area); fire and the evolutionary ecology of plants; fire, competition and the organization of communities; fire and management; and fire and the ecology of a changing world. -S.R.Harris
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Four major forest types are currently present in the central African rainforest; mixed forest, Marantaceae forest, monodominant Gilbertiodendron forest and swamp forest. These forest types span vast areas and demonstrate highly significant differences in diversity and productivity; yet factors responsible for their formation are poorly understood. One hypothesis is that they are as a consequence of different intensities of past human activity, in particular burning. Here we present results from fossil charcoal contained in 12 sediment cores spanning the last 2500 yr and covering a spatial area of more than 900 km2. These records demonstrate that burning started in the last 1100 yr with areas currently covered by Marantaceae forest undergoing more frequent burning events than the other forest types. In comparison monodominant Gilbertiodendron forest appear to have undergone large burning events only in the past 200 yr. These records also demonstrate a lack of spatial relationship between fire events at the different sites (discontinuous and asynchronous) suggesting that these fires resulted from localised burning events probably caused by human ignitions. Whilst the large spatial scale of past human activities in the South American rainforest is now widely acknowledged, these results indicate, for the first time, the significant impact that early human populations had on the community composition of central African rainforest.
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Earth's climate is changing. Effects of climate change on fungal distribution and activity are hard to predict because they are mediated in many different ways, including: fungal physiology, reproduction and survival, host physiology, spatial and temporal distribution of hosts, resource availability and competition. Currently it is hard to monitor such effects on fungal mycelium in the field, but fruit bodies provide a useful surrogate. Here we review the effects of climate change on phenological changes in fungal fruiting and fruit body yield, and on fungal hosts and distribution, particularly of saprotrophic and ectomycorrhizal basidiomycetes. We report that fruiting phenology is changing in many European countries: on average, the fruiting season is extending, though for some species it is contracting; different species and ecological groups behave differently; time of fruiting depends on geographical location; some fungi now fruit early in the year as well as in autumn, and spring fruiting is getting earlier; some fungi appear to be changing hosts; fruit body yields vary dramatically from year to year; the amount, duration and frequency of fruiting are influenced by numerous environmental factors. We also consider difficulties in assessing phenological and distributional data, and provide suggestions for future research directions at the interface of laboratory experiments and field observations, including molecular approaches and monitoring systems.