02177nas a2200241 4500008004100000245014500041210006900186300001200255490000800267520142800275100001701703700001601720700001301736700001901749700001901768700001701787700001401804700001301818700001401831700001801845700001701863856005501880 2018 eng d00aPlant functional group influences arbuscular mycorrhizal fungal abundance and hyphal contribution to soil CO2 efflux in temperate grasslands0 aPlant functional group influences arbuscular mycorrhizal fungal  a157-1700 v4323 a

Background and aims: Arbuscular mycorrhizal (AM) fungi are abundant in grassland ecosystem. We assessed AM hyphal contributions to soil CO2 efflux across plant functional groups to better quantify AM fungal influences on soil carbon dynamics.


Methods: We conducted a field experiment using in-growth mesocosms to partition soil CO2 efflux from roots, AM hyphae, and free-living soil microbes associated with C3 grasses, C4 grasses, forbs, and diverse plant communities from May to August in 2017.


Results: AM hyphae contributed <10% to total soil respiration in forb communities and diverse plant communities but accounted for as much as 32% in C3 grasses. Plant functional groups differed in hyphal production efficiencies (the ratio of AM hyphal length to aboveground biomass), with the lowest in C3 grasses (0.47?±?0.15 m g-1) and the greatest in forbs (3.27?±?0.55 m g-1). Mowing reduced hyphal production efficiency of C4 grasses and forbs but did not affect total soil respiration. AM hyphal and microbial respiration peaked at the middle of the growing season, however there was no significant seasonal variation in root respiration.


Conclusion: AM hyphal respiration is an important pathway of carbon flux from plants to atmosphere. Shifts in plant community composition can influence soil carbon processes by regulating hyphal production and respiration.

1 aGui, Weiyang1 aRen, Haiyan1 aLiu, Nan1 aZhang, Yingjun1 aCobb, Adam, B.1 aWilson, G.T.1 aSun, Xiao1 aHu, Jian1 aXiao, Yan1 aZhang, Fengge1 aYang, Gaowen uhttp://link.springer.com/10.1007/s11104-018-3789-0