| Biodiversity is the core element of tourism ecosystem. The rapid development oftourism inevitably brings about negative effects on the ecological environment,intensifying the contradiction between environmental protection and utilization. There is aconsiderable wealth of information regarding the species diversity of both plants andanimals that occur above ground. However, little attention has been paid to the largeamounts of microorganisms under the ground, which are important components of tourismecosystem and play vital roles in nutrient cycling and energy flux.Arbuscular mycorrhizae (AM) are ubiquitous symbioses between plant roots and AMfungi in terrestrial ecosystems. Arbuscular mycorrhizal fungi are important soil microbialresources that help to integrate plants with soil. When there is a change in this dynamic, tosome extent it reflects the impact that disturbance caused by tourists has on the ecosystem,and thus indirectly helps us to understand the state of health of the ecosystem. In this study,the work will focus on the “plant-AM fungi-soil” circle of the tourism ecosystem, usingmycorrhizal and tourism ecological principles and research methods. A study will be madeof the response of AM fungal community structure, the “plant-fungi” symbiont, AMmycelium network, and glomalin-related soil protein as a result of disturbance by tourists.The study will explain the ecological function of AM fungi in the tourism ecosystem andthe ecological value of AM fungi as an environmental indicator organism. It will alsoprovide valuable reference materials for the sustainable development of tourism.The diversity of AM fungi in the soil of Huangshan were investigated. Twenty-fivespecies of arbuscular mycorrhizal fungi were identified from42rhizosphere soil samples.Acaulospora, Glomus and Funneliformis were dominant at the study site. AM fungi sporedensity ranged from45to3250per100g soil (average839), and the species richness ofarbuscular mycorrhizal fungi ranged from1-9(average4.2) per soil sample.Shannon-Wiener index and Simpson’s index were calculated to evaluate the arbuscularmycorrhizal fungal diversity. The diversity of AM fungal community in the subtropicalforest of Huangshan may be the result of mutual selection between AM fungi and theecological environment.Root and rhizosphere soil samples of preserved plant Huangshan Magnolia(Magnolia cylindrica) were studied to determine the root colonization and the diversity of spore populations of AM fungi. The results showed that AM fungal colonization structuresincluding hyphae, hyphal coils and vesicles were present in all root samples. Paris-typearbuscular mycorrhizae were identified in the roots according to the morphologicalstructure. Seventeen species of AM fungi were isolated and identified from therhizosphere soil samples.Tourism disturbance influenced the AM fungi colonization rate, the amount of soilmycelium, spore density and GRSP content. The influence was greatest within5m awayfrom the tour trail. In some area, the influence could extend to10m and even farther. Indifferent habitats, the disturbance on AM fungi community varied in degree and scope. Itwas greater in Wenquan, Yungu Si and Guangmin Ding. The reason may be related tovegetation type, soil factors, disturbance intensity, disturbance history and so on. Differentdegrees of tourism construction will significantly affect AM fungi community. Thedisturbance was greatest in Yungu Si, Ciguang Ge followed by and Diaoqiao An was theleast. The GRSP content of Diaoqiao An was24.41mg/g soil,5-19times that of othersites.Road construction had obvious disturbance on AM fungal diversity. The Shannondiversity index, evenness and Simpson diversity index fell to1.74,0.57and0.83respectively after road construction. The decline mainly reflected in the number of spores,reducing by83%, while the species composition of AM fungal communities did notchange significantly. Although there is a slight decrease in species richness, but somedominant species did not change before and after the disturbance, which still play a keyrole in the AM fungal community composition.Tourism had posed negative influence on the Huangshan ecosystem. The resultrevealed that the AM fungi community showed strong adaptation (resilience) to thedisturbance. Different AM fungal species has different ability to adapt to differentenvironmental disturbances. More attention should be paid to the advantages of AMfungal populations with a high degree of tolerance in the disturbance environment, forthey may be of great significance in repairing and reconstruction of the ecosystem. |
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