Winter grazing, not fencing or unicast, promotes stability of microbial
community and function in the Qilian Mountains of Qinghai-Xizang Plateau
Abstract
Microorganisms play a key role in maintaining the stability of
vegetation-soil-microbial systems and terrestrial geochemical processes
in alpine meadows. To investigate the effects of different management
practices on the structure and function of microbial communities, the
present study used metagenomic sequencing to investigate the structure
and function of soil microbial communities in the southern Qilian
Mountains of the Qinghai-Xizang Plateau in response to the management
practices of fenestration (FE), winter grazing (WG), transition zone
between natural and artificial grasslands (TZ), and artificial unicast
oats (AU). The management measures significantly changed vegetation
diversity and soil physicochemical properties. The prokaryotic community
structure was considerably similar in FE and WG, as well as in TZ and
AU. Near-natural (FE) and artificial establishment (AU) disturbances
changed the fungal community structure. Enzymes related to carbon
metabolism did not respond significantly to the management measures,
whereas those related to nitrogen metabolism did not respond
significantly in TZ and AU. The relative abundance of enzymes involved
in nitrogen metabolism was higher under TZ and AU than under FE and WG.
We concluded that grassland management measures altered the structure of
aboveground graminoid and leguminous vegetation communities and
belowground biomass allocation, resulting in changes in K uptake,
causing significant changes in the structure of fungal communities and
nitrogen-metabolizing enzymes; moderate disturbance (WG) was beneficial
for maintaining the stability of microbial communities in alpine
grasslands.