@article {KNZ001981, title = {Phosphorus and mowing improve native alfalfa establishment, facilitating restoration of grassland productivity and diversity}, journal = {Land Degradation \& Development}, volume = {30}, year = {2019}, pages = {647 - 657}, keywords = {LTER-KNZ}, doi = {10.1002/ldr.v30.610.1002/ldr.3251}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/ldr.3251}, author = {Zhou, Jiqiong and G.T. Wilson and Cobb, Adam B. and Yang, Gaowen and Zhang, Yingjun} } @article {KNZ001903, title = {Long-term effects of grazing and topography on extra-radical hyphae of arbuscular mycorrhizal fungi in semi-arid grasslands}, journal = {Mycorrhiza}, volume = {28}, year = {2018}, pages = {117 - 127}, abstract = {

Grazing and topography have drastic effects on plant communities and soil properties. These effects are thought to influence arbuscular mycorrhizal (AM) fungi. However, the simultaneous impacts of grazing pressure (sheep\ ha-1) and topography on plant and soil factors and their relationship to the production of extra-radical AM hyphae are not well understood. Our 10-year study assessed relationships between grazing, plant species richness, aboveground plant productivity, soil nutrients, edaphic properties, and AM hyphal length density (HLD) in different topographic areas (flat or sloped). We found HLD linearly declined with increasing grazing pressure (1.5-9.0 sheep\ ha-1) in sloped areas, but HLD was greatest at moderate grazing pressure (4.5 sheep\ ha-1) in flat areas. Structural equation modeling indicates grazing reduces HLD by altering soil nutrient dynamics in sloped areas, but non-linearly influences HLD through plant community and edaphic changes in flat areas. Our findings highlight how topography influences key plant and soil factors, thus regulating the effects of grazing pressure on extra-radical hyphal production of AM fungi in grasslands. Understanding how grazing and topography influence AM fungi in semi-arid grasslands is vital, as globally, severe human population pressure and increasing demand for food aggravate the grazing intensity in grasslands.

}, keywords = {LTER-KNZ}, doi = {10.1007/s00572-017-0812-x}, url = {http://link.springer.com/10.1007/s00572-017-0812-x}, author = {Ren, Haiyan and Gui, Weiyang and Yongfei Bai and Stein, Claudia and Rodrigues, Jorge L. M. and G.T. Wilson and Cobb, Adam B. and Zhang, Yingjun and Yang, Gaowen} } @article {KNZ001900, title = {Plant functional group influences arbuscular mycorrhizal fungal abundance and hyphal contribution to soil CO2 efflux in temperate grasslands}, journal = {Plant and Soil}, volume = {432}, year = {2018}, pages = {157-170}, abstract = {

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.

}, keywords = {LTER-KNZ}, doi = {10.1007/s11104-018-3789-0}, url = {http://link.springer.com/10.1007/s11104-018-3789-0}, author = {Gui, Weiyang and Ren, Haiyan and Liu, Nan and Zhang, Yingjun and Cobb, Adam B. and G.T. Wilson and Sun, Xiao and Hu, Jian and Xiao, Yan and Zhang, Fengge and Yang, Gaowen} } @article {KNZ001904, title = {Trichoderma biofertilizer links to altered soil chemistry, altered microbial communities, and improved grassland biomass}, journal = {Frontiers in Microbiology}, volume = {9}, year = {2018}, pages = {848}, abstract = {

In grasslands, forage and livestock production results in soil nutrient deficits as grasslands typically receive no nutrient inputs, leading to a loss of grassland biomass. The application of mature compost has been shown to effectively increase grassland nutrient availability. However, research on fertilization regime influence and potential microbial ecological regulation mechanisms are rarely conducted in grassland soil. We conducted a two-year experiment in meadow steppe grasslands, focusing on above- and belowground consequences of organic or Trichoderma biofertilizer applications and potential soil microbial ecological mechanisms underlying soil chemistry and microbial community responses. Grassland biomass significantly (p = 0.019) increased following amendment with 9,000 kg ha\−1 of Trichoderma biofertilizer (composted cattle manure + inoculum) compared with other assessed organic or biofertilizer rates, except for BOF3000 (fertilized with 3,000 kg ha\−1 biofertilizer). This rate of Trichoderma biofertilizer treatment increased soil antifungal compounds that may suppress pathogenic fungi, potentially partially responsible for improved grassland biomass. Nonmetric multidimensional scaling (NMDS) revealed soil chemistry and fungal communities were all separated by different fertilization regime. Trichoderma biofertilizer (9,000 kg ha\−1) increased relative abundances of Archaeorhizomyces and Trichoderma while decreasing Ophiosphaerella. Trichoderma can improve grassland biomass, while Ophiosphaerella has the opposite effect as it may secrete metabolites causing grass necrosis. Correlations between soil properties and microbial genera showed plant-available phosphorus may influence grassland biomass by increasing Archaeorhizomyces and Trichoderma while reducing Ophiosphaerella. According to our structural equation modeling (SEM), Trichoderma abundance was the primary contributor to aboveground grassland biomass. Our results suggest Trichoderma biofertilizer could be an important tool for management of soils and ultimately grassland plant biomass.

}, keywords = {LTER-KNZ}, doi = {10.3389/fmicb.2018.00848}, url = {http://journal.frontiersin.org/article/10.3389/fmicb.2018.00848/full}, author = {Zhang, Fengge and Huo, Yunqian and Cobb, Adam B. and Luo, Gongwen and Zhou, Jiqiong and Yang, Gaowen and G.T. Wilson and Zhang, Yingjun} }