Studies On Macrofungi Diversity In Alpine Forests Regions Of Tibet

Biodiversity is the foundation of human survival and the important material guarantee of human society development, however, fungal species resource is "understudied"in China. The fungal resources in alpine forests regions of Tibet has been poorly studied because of high attitude and poor road access. On-the-spot surveys combined with investigations at fixed spots was taken. The aim of this study was to survey macrofungal species systematically and resources in alpine forests regions of Tibet, discuss the relationship between macrofungi occourance and forest vegetation as well as other environmental conditions in alpine forests regions of Tibet. This will lay the foundation for the conservation and utilization of macrofungi.In species diversity, more than1100specimens were collected in Tibet and239species were identified. According to classification and identification,239species belong to118genera,44families,16orders,4classes,2phylum. Among them:222species from11orders,34families,106genera belong to Basidiomycota;17species from3classes,5orders,10families12genera belong to Ascomycota. It included3new species,1new species to be determined,2new records for China and22new records for Tibet. Gastroboletus thibetanus, Agrocybe biformata and Clitocybula abietis were three new species. G. thibetanus was collected under Abies georgei var. smithii in Mt. Sejila and is characterized by pale green-yellow to coral red basidiomata, a percurrent columella and relatively large basidiospores. A. bifomata, was collected in Cyclobalanopsis glauca forest and is characterized by light brown pileus, absence of a membranous annulus,2-spored basidia, spores with one or two germ pores, absence of pleurocystidia and the woody habitat. C. abietis was collected on the rotten wood of A. georgei var. smithii. It is characterized by gray black pileus, pilocystidia restricted in central pileus, present caulocystidia, absent pleurocystidia and cheilocystidia. Panaeolina macrospora was the new species to be determined. Stereopsis humphreyi and Astreatus koreanus were two new records for China. The morphology and distribution of each species was described and the relationship of related species was discussed. Twenty new records for Tibet include Panaeolus acuminatus; Pseudohydnum gelatinosum; Macrolepiota excoriate; Sarcosphaera coronaria; Cystoderma granulose; Asterophora lycoperdoides; Neolentinus lepideus; Cudonia japonica; Callistosporium luteo-olivaceum; Cortinarius cinnamomeus; Hygrophoropsis aurantiac; Boletus pseudocalopus; Otidea leporine; Panaeolus semiovatus; Agrocybe elatella; Lentinus suavissimus; Cudonia circinans; Amanita fritillaria; Psathyrella candolleana; Polyporus badius; Xerula strigosa; Mitrula paludosa. The diversity catalogue of all species was arranged according to Index fungorm. All specimens are deposited in the Herbarium of Mycology of Jilin Agricultural University (HMJAU).The fungi flora was very abundant in alpine forests regions of Tibet. Agaricaceae, Russulaceae, Boletaceae, Polyporaceae, Cortinariaceae, Strophariaceae and Tricholomataceae, with118species,49.37%of the mount of macrofungi in the Tibet, belonged to the families which were not less than10species and these families were widespread in the world and North Temperature Zone. Six genera including Cortinarius, Lactarius, Amanita, Boletus, Suillus and Inocybe belonged to the dominant genera. Cosmopolitan species and North Temperature Zone species (87.12%) were main distribution species. Eurasian species, China-Japan species and Temperate-Subtropical or tropical species (11.60%) also had many species in this district.The nutritional mode and substrate preference of macrofungi in alpine forests regions of Tibet were also investigated in this study. They were divided into saprophytic, parasitic and mycorrhizal fungi based on their nutritional mode. Only one species, Asterophora lycoperdoides, was found to be parasitic. The ratio of saprophytic fungi was39.38%and mycorrhizal fungi was up to60.18%. According to substrate preference, they were divided to four types, soil-dwelling, wood-decay, litter-decay and fungi-parastic, holding63.00%,34.80%,1.76%and0.44%, respectively.The relationships among macrofungi diversity, forest vegetation type and many factors relating to macrofungi occourance were studied in nine sampling plots of three sites by two-year investigation. It demonstrated that the species richness index and diversity index calculated by software R in the sampling plots of Abies georgei var. smithii. was greater than those of mixed forest dominated by Cyclobalanopsis glauca and Larix gmelinii, and the latter was greater than those of C. glauca. CCA, canonical correspondence analysis, was used by software Canoco4.5to analyse the relationship among sampling plots, environmental factors and macrofungi species occurance. It was concluded that the environmental consistency existed in the sampling plots of the same forest type; the occourance of macrofungi species was drived by different environmental factors; there was some contribution of both plant type and the environmental factors on the occourance.It also illustrated that the species and quantities of macrofungi were greatly related to rainfall and no correlation was found between macrofungi occourence and temperature in its growing seasons.On the bases of present species endanger and protection levels, the evaluation methods of endangering grade of macrofungi in alpine region of Tibet were studied and discussed. Many spore prints, cultures and DNA meterials were acquired from field work and the conservation of macrofungi in alpine region of Tibet was briefly discussed.In the further study, it needs data sets of larger, spatial and temporal scales to conclude the occurance of fruiting bodies affected by biotic and abiotic factors, including plants, animal, soil, climate and other site factors.