Function and functioning mechanisms of mycorrhizal fungi under global changes

Abstract

Global changes with regards to climate, environment, economy and society may cause serious problems and in the meantime also challenges for terrestrial ecosystems. Example global changes include greenhouse effects, ozone depletion, acid deposition, drought and waterlogging frequency, higher and lower temperature duration, soil acidity and degradation, soil polluted with heavy metals, sharp decline of forest area and species diversity etc. It is well documented that biogeography environments and climates play key roles in species distribution, while global changes affect the distribution and utilization of species resources. As the most intimate partner to plants, mycorrhizal fungi are also seriously influenced. Mycorrhizal fungi which colonize plant roots and form symbiosis with host plants, occupy irreplaceable niche. Mycorrhizal associations specifically arbuscular mycorrhiza (AM) , ectomycorrhiza (ECM) , ectoendomycorrhiza (EEM) , ericoid mycorrhizas (ERM) , and / or orchid mycorrhizas (OM) , interact with other organisms living both in soil and on the ground, incorporate nutrient transforming, absorption, circulation and utilization. They play vital roles in maintaining atmospheric compositions, adjusting terrestrial ecosystems, increasing biodiversities, stabilizing sustainable productivities as well as sustainable development of human society. Thus, exploration of the function and functioning mechanisms of mycorrhizal fungi under global changes is a complete new subject, especially, the study on biological mechanisms to global changes is of realistic value and profound scientific significance. This paper introduces the impact of global changes on mycorrhizal fungi, particularly the influence of greenhouse effects, CO 2 level increasing, ozone depletion, acid with nitrogen and sulfur deposition, drought and waterlogging, exotic plant invasion, and human activities on mycorrhizal fungus development and functions. We summarized the possible functions of mycorrhizal fungi under global changes through direct and indirect pathways, such as rehabilitating and stabilizing the damaged, degraded and fragile ecosystems, deceasing CO 2 http: / / www.ecologica.cn concentration in the atmosphere, increasing carbon sink, enhancing substance conversion, circulation and utilization, resisting to plant pathogens and pest insects, conferring biological stresses, and playing some roles in exotic plant invasion and succession. The authors also reviewed the functioning mechanisms of mycorrhizal fungi under global changes. It was suggested that mycorrhizal fungi may synergistically function with the other organisms, strengthening their own and host plant physiological and ecological characteristics, enlarging hyphae net, and secreting and inducing beneficial substances. Therefore the position, role, function and mechanisms of mycorrhizal fungi under global changes, especially the evolution characters of mycorrhizal fungi and mycorrhizas, the role and functions of mycorrhizal fungi under global changes and possible mechanisms of r...

Research on the Model of influencing factors of strain decomposition rate based on Analytic hierarchy process

“…Fungal activity model is used to analyze the effect of a single strain on the decomposition rate. Comprehensive considering external factor such as temperature, we build a fungal activity model to describe the behaviour of decomposition under the common influence of humidity and temperature [3]. After calculating some parameters, we can obtain the relationship between decomposition rate and growth rate of one certain fungus.…”