THE INDICATIVE SIGNIFICANCE OF SPORES OF COPROPHILOUS FUNGI IN PALAEOECOLOGICAL RESEARCH

Spores of fungi growing on feces have been highlighted as an important potential proxy to reconstruct large herbivore densities in past landscapes.In more recent studies of sediments,changes in the abundance of spores of these fungi have been used as a proxy to define megafaunal population presence,decline,and extinction.Podospora-,Sordaria-and Sporormiella-type are the most reliable indicators of large herbivore population densities.Records of Sporormiellaspores are directly linked to the extinction of megaherbivores,for example,a few recent studies have used Sporormiellaas a proxy to test hypotheses and to draw conclusions regarding the causes of the end-Pleistocene megafaunal extinction in North America.In addition to the information based on coprophilous fungal taxa,some other fungal spore types,are valuable paleo-environmental indicators,the ascospores of Neurosporaindicate local fires.The chlamydospores of Glomus grow below the soil surface and therefore the presence of chlamydospores in lake deposits indicates soil erosion in the lake catchment.Some other fungal taxa show a host-parasite relationship,like Amphisphaerelladispersellathat is linked to the occurrence of Populus.Type 18 and type-18 bindicate humidity and Type 200-type,Type 12-type and Type 306-type droughts.Sudden maxima appeared in the presence of ascospores of the tree-parasite Kretzschmariadeustain lake deposits indicate the erosion of forest soils during rainstorms,and so on.Further research is needed,however,to improve identifications for other less common types to ensure that they become robust and reliable indicators.Some fungal spore types which are good indicators for local environmental conditions have been illustrated and interpreted.In China palynological studies including the analysis of fungal spores have not yet been carried out so far.In this paper,a brief introduction to research methods and principles is given,and recent advances of records of fossil dung fungal spores are given,as these fungi are valuable new indicators for domestic paleoenvironments and therefore the analysis of fungi,in combination with pollen analysis,should be applied in future palaeoecological studies.