On some agarics occurring in carr forests

Remarks on ecology of several small agarics growing in carr forests of Querco-Ulmetum minoris and Astrantio-Fraxinetum type are presented and discussed. They all occupy special microhabitat (bare ground), belong to certain functional group (saprotrophs) and seem to be connected with carr forest habitat. The base rich or neutral soil humus, generally not favoured by fungi, together with extreme moisture and fast decomposition of litter causes that some humicolous macrofungi in carr forests form mostly small and short-living fruit bodies of hygrophyte character. They represent several genera: Conocybe, Coprinus, Cystolepiota, Entoloma, Flammulaster, Lepiota, Melanophyllum and Pholiotina of the order Agaricales. New localities are given, ecological amplitude is analised and preliminary mycosynusial consideration is presented.

The nature of substratum and moisture conditions play the most important role in the development and the distribution of fungi.carr forests with their luxuriant vegetation, high humidity and rich soils are habitats distinguished by diversified and specific mycobiota, heterogenous in biological respect, comprising various saprotrophic and biotrophic fungi (Bujakiewicz 1989(Bujakiewicz , 1992)).
The goal of this paper is to turn the attention on the occurrence of several saprotrophic terrestrial agarics confined to naked humose soil observed in several studied phytocoenoses of the carr forests.Those fungi inhabit and exploit special microhabitat (rich humose soil) and express specific and variable composition of assemblages consisting emphemeral fructifications.They tend to occur simultaneously and repeatedly in similar habitat in many localities, manifesting some degree of dependence on carr forest habitat.
Macrofungocoenosis is regarded as intrinsic part of the plant community (Arnolds 1988(Arnolds , 1992)).It comprises various groupings of fungi as regards to substratum, called mycosynusia.From three types of dependence of synusiae distinguished by Barkman (1973): ecological, topographical and syntaxonomic one, the latter is accepted in this paper.

MATErIALs And METhods
The material for analysis was gathered from 10 localities (Fig. 1) and 15 observation plots taken from unpublished master theses (mscr.)and from authors unpublished data (Tab.1).Master theses used in this publication were done within the period of 30 years, so degree of recognition of taxa, nomenclature and methods of study are very diversified.
only 14 terrestrial saprotrophic species of macrofungi out of 90 taxa representing that niche-substrat group were selected and subjected to a comparative analysis in respect of relationship to carr forest habitat.They fulfill several significant requirements: occur in carr forests, form fructifications directly on naked humose ground, and their habitat preferences are confirmed in various ecological elaborations and monographs.The statement that species considered are saprotrophic and humicolous is based on the authors own observations and on literature accounts (e.g., Knudsen, Vesterholt 2008;horak 2005) however it is obvious that in the field study a sharp line between soil and litter fungi is hard to detect and often not recognized.
data originate from observations performed in phytocoenoses of the Querco-Ulmetum minoris and the Astrantio-Fraxinetum associations occurring in the Pojezierze Wielkopolsko-Kujawskie lakeland and in the Pojezierze Lubuskie lakeland.(Fig. 1).The soil in the carr forests was treated to be a homogenous substratum.Analyses of soil profile were not performed.
The observations are based on the occurrence of fruit-bodies.In Table 1 the temporal frequency is given and the abundance of fruit bodies acc. to nespiak (1959) and Jahn et al. (1967).
The nomenclature of the considered macrofungi is according to Knudsen and Vesterholt (2008) and hausknecht (2009) and the geographical divisions of the area -after Kondracki (2001).numerals of localities are given in bold types.rEsULTs on the basis of gathered materials, short description of localities and ecological and chorological characteristic of selected macrofungi are given.Fungal species names are maintained original as in given theses but names of species selected to analysis are kept modern (Tab.1).In the lists of species within the localities (1-10) current names or synonyms of fungi considered in the present paper are given in bold types.
Table 1 occurrence of selected agaric species in phytocoenoses of some carr forests in Wielkopolska region and Ziemia Lubuska ii Lepiota tomentella
Macrofungi chosen for the discussion are rather rare however widespread.They grow in temperate deciduous forests especially in azonal carr forest of various types mostly in autumn and include members of the following families of the order Agaricales: Agaricaceae Macrofungi considered have perennial mycelium which penetrates the surface level of soil profile to the depth of several cm.Their fruit bodies grow directly on bare, black humose ground, sometimes on conspicuously separated small lumps of earth or on caprolites.They were often observed growing close to rhizomes of Anemone spp.and bulbils of Ficaria verna.only few of them are rarely and accidentally noted on dead plant remains.All are lignin decomposers.
Mostly due to delicate nature and small size of fruit bodies those species are not easily discernible and frequently overlooked.
It is clearly visible that selected macrofungi occur sparingly, rarely and scarcely and represent low degrees of frequency (Bujakiewicz 1989) (Tab.1).The taxa are often not noticed during the visits because of short duration of sporocarps even if annual, temporal and spatial frequency of observations is high.small and ephemeral fruit bodies of Coprinus cortinatus lasts only few hours, those of Pholiotina maireione or two days and those of Melanophyllum haematospermum -several days.They all are confined to black humus (especially Lepiota echinella, L. tomentella, Melanophyllum haematospermum and Pholiotina mairei) some are confined to nitrogen in soil [(e.g., Entoloma pleopodium (noordeloos 1992) and Conocybe arrheni (Ludwig 2007)] and others prefer calciphilous soil, e.g., Cystolepiota bucknalli, C. seminuda and Melanophyllum haematospermum (herink 1989;Ludwig 2001).The last species is encountered even in greenhouses (Ludwig 2001).
data on the occurrence of some species on litter or even woody detritus, e.g., Entoloma strigosissimum, Flammulaster granulosus and Melanophyllum haematospermum (Ludwig 2001(Ludwig , 2007) may be connected with a specific habitat conditions in carr forests.Flooding usually covers plant remains (logs, branches, twigs etc.) with a thick deposits of silt and mud and smooth over substratum details.In that conditions it is often difficult or impossible to determine nutrient base.
Terrestrial character of this species and connection with base rich soils is stressed by Watling (1982Watling ( ), horak (2005) ) and Knudsen, Vesterholt (2008).Ludwig (2007) noted this rare species both on naked soil and on small woody debris.
Cystolepiota bucknallii is rare in Poland and up to now recorded in three localities only, i.e. in beech forest in calcareous mountains (Gumińska 1972) and in Querco-Ulmetum minoris (Bujakiewicz 2001).
This holarctic species is rather common in Western Europe, rare in central Europe and is considered to be titly bound with calcareous soils (Kreisel 1987;Ludwig 2001).According to darimont (1975) it is characteristic species of the fungal community ("sociomycie") Lepiotetum bucknallii wich occurs in phytocoenoses of the Acereto-Fraxinetum (Gradmann) Tüx.association in east belgium montane forests.
This species is considered to be rare (Kreisel 1987), growing on rich and moist soils (horak 2005;Knudsen, Vesterholt 2008) in most cases in deciduous forests, occasionally on calcium rich soil (Kreisel 1987).
Lepiota tomentella occurs in diverse alluvial and riparian forests, especially in Fraxino-Alnetum, in forests of the rhine valley and is strongly threatened (Krieglsteiner 2003).It is also endangered (E) in Poland (Wojewoda, Ławrynowicz 2006).
This species was formerly treated as rare but recently has expanded its distribution.It is connected with rich, fertile soils mainly of carr forests but grows also on compost piles and in ruderal places sometimes even in greenhouses (Ludwig 2001;horak 2005;Knudsen, Vesterholt 2008).According to Kreisel (1987) it is probably nitrophilous and often synantropic.Its fruit bodies were found also on woody detritus (Ludwig 2001) or even on decaying wood (Kreisel 1987(Kreisel ). rimóczi (1994) ) stresses its occurrence in aspen-poplar woodlands where soil reaction is 8.1.
Pholiotina arrhenii seems to be rare in Poland.It was noted up to now in three localities, namely: in the Querco-Ulmetum association (Bujakiewicz 2001), in mixed Pino-Quercetum association (Wojewoda 1974) and in the botanical garden (Lisiewska, Mikołajczak 1998).It was recently recorded in manorial parks and oak woodlands (Kujawa 2008).
This taxon was only recently recognized in Poland and seems to be widespread but not common.It has only three localities up to now, namely in riverine forests with Alnus incana (Bujakiewicz 1993) and in the Querco-Ulmetum minoris association (nita, Bujakiewicz 2005Bujakiewicz , 2007)).
horak (2005) recognized Entoloma dysthaloides as associated with carr forests, noordeloos (1992) and Ludwig (2007) recorded it in wet places in deciduous forests often under Alnus and Fraxinus.
Entoloma strigosissimum is considered to be rare in Europe and seems to have a wider ecological amplitude.It has also wider nutrient base tolerance growing sometimes on decaying wood (noordeloos 1992;Krieglsteiner 2003;Ludwig 2007;Knudsen, Vesterholt 2008). horak (2005) defines is as terrestrial and lignicolous growing in carr forest and dry meadows.
dIscUssIon And concLUsIons Mycocoenological studies, performed on permanent plots laid out in phytocoenoses of the strictly determined plant associations are the best method of studying the behaviour of fungi.The abundance of the fungi is determined by counting the fruit bodies.observation plots visited through at least 3 years and performed two or three times per month in the growing season ensure to include the majority of components of mycocoenosis.during such intensive studies also specific fungal sporocarp nature, including short duration, periodicity and fluctuation in fruiting can be controlled to a certain degree.
Macrofungi have a great ecological, syntaxonomical and indicator value in all biocenoses.due to narrow ecological susceptibility they are sensitive indicators of habitat conditions and can be differential species at least locally, of various phytocoenological syntaxa.
The development of fungus fruit bodies depends on ecological conditions of phytocoenosis as a whole.Fruit bodies are not randomly distributed but always according to some kind of interdependence (states 1981).
From the three main trophic (functional) groups, saprotrophic fungi are the most numerous.In carr forests lignicolous and litter saprothrophs predominate.humicolous saprobionts are less numerous whereas perform unique species composition.
humus may be considered an end product in the decomposition of lignin either from wood or herb layer.It is the amorphous dark brown or black organic material in the soil, distinct from partially decomposed plant and animal detritus.humus is slowly decomposed by soil organisms, mostly fungi.Fungal habitat preferences are based on enzyme system adaptable to use by the fungus of specific fraction of the substratum such as cellulose, lignin, chitin and other compounds.Various species of fungi break down cellulose and hemicellulose but few only, comprising the considered taxa, are involved in lignin decomposition.Lignin is almost exclusively broken down by basidiomycete fungi, mostly macrofungi.
The base rich or neutral habitat of carr forests attracts the very specific and selected group of terrestrial fungi.decomposition of litter in carr forests is very fast and the majority of this year litter being decayed in one year (dziadowiec 1987).
Inspite of lush vegetation many phytocoenoses of carr forests especially of the Astrantio-Fraxinetum and Querco-Ulmetum minoris associations are distinguished by clearly visible surfaces of naked humose ground, free of herb layer.These places are often occupied by humicolous macrofungi.sporocarps of those macrofungi are variable in appearance and periodicity.That is why they are not present in all stands considered and during all years of visits (Tab.1).Usually only few species in mycocoenological observation plots is found to form fructifications each year within a period of three or more years.They are underrepresented in some phytocoenoses or even absent.It may be caused not only by short duration and periodicity of sporocarps.In some stands it is due to qualitative fluctuations when sporocarps of a species are completely absent during several years of study.Qualitative fluctuations are mostly caused by weather conditions but also ecological factors, like litter decomposition to humus form etc.
Ecological behavior and requirements of the 14 selected species of humicolous macrofungi incline to treat them as species more linked to habitat of certain phytocoenological syntaxa then litter saprotrophs and any other functional groups.They seem to form distinguishable element of a terminal stage of decomposition of lignin compounds in the humus.They form synusia-like grouping of humicolous saprotrophs, which may be provisionally called Pholiotina mairei -Entoloma pleopodium prov.grouping.components of this fungal assemblage appear repeatedly or occur changeable in different localities (Tab.1).
This humicolous synusium or some of its representatives seems to be differential for almost all types of the carr forests of the alliance Alnion incanae (previous Alno-Padion or Alno-Ulmion) inspite of the diverse trophic and moisture conditions.The uniformity of the microhabitat enables the uniformity of the fungal assemblage.
It is reasonable to recall here darimont's (1975) autonomous sociomycie of Lepiotetum bucknallii, described in phytocoenoses of the Acereto-Fraxinetum association in montane forests in East Belgium.synusial similarities with an assemblage of saprotrophic humicolous macrofungi occurring in carr forests, remind this sociomycie.This community however is nitrophilous and hygrophilous and belongs