Ecology of myxomycetes of a winter-cold desert in western Kazakhstan

The moist chamber culture technique was used to study the ecology of myxomy cetes from a winter-cold desert of the Mangyschlak Peninsula (western Kazak hstan). A rather species-poor community of 27 myxomycete taxa, two protoste lids and some undifferentiated myxobacteria was found. The rank-abundance p lot is described best by a log series or a geometric model. The species tha t developed formed a successional sequence that correlated well with morpho logical features of the fructifications. Using canonical correspondence ana lysis, environmental parameters recorded within substrate sampling were rel ated to species abundances. Substratum type and pH accounted for most of th e variance in species distribution. Using five environmental parameters and development time as resource states, niche breadths were calculated for th e 18 most common species in the study. Bark-inhabiting species were found t o be more specialized than those inhabiting litter. Members of the first gr oup tend to develop rapidly, have small, usually stalked sporocarps without a peridium and possess protoplasmodia or minute aphanoplasmodia. Members o f the second group tend to have a phaneroplasmodium and develop more slowly into larger, usually sessile fructifications with often well-developed per idia. A plot of niche overlap vs Cole index of association for the most com mon species revealed frequent associations among species with small sporoca rps and proto- or aphanoplasmodia. In contrast, litter-inhabiting species w ith phaneroplasmodia seem to avoid each other. Myxomycetes in the investiga ted winter-cold desert behaved as rather opportunistic k-strategists, quick ly using all temporally and spatially changing microhabitats.