Grazing practices affect phyllosphere and rhizosphere bacterial communities of Kobresia humilis by altering their network stability.
Sci Total Environ
; 900: 165814, 2023 Nov 20.
Article
em En
| MEDLINE
| ID: mdl-37517723
ABSTRACT
The primary utilization strategy for meadow grasslands on the Qinghai-Tibet Plateau (QTP) is livestock grazing. This practice is considered as one of the major drivers of plant-associated bacterial community construction and changes in soil properties. The species of Kobresia humilis is considered as the most dominant one in grasslands. However, how different grazing practices affect the phyllosphere and rhizosphere bacterial communities of K. humilis is unknown. To address this issue, the effects of the grazing enclosure (GE), single-species grazing (YG and SG, representing yak only and sheep only, respectively), and different ratios of grazing (ratio of yak to sheep is 12, 14, and 16, represented by MG12, MG14, and MG16, respectively) on the dominant plant of K. humilis, it's phyllosphere and rhizosphere bacteria, and soil properties were investigated using artificially controlled grazing and grazing enclosure. Our data showed that grazing enclosure enhanced vegetation coverage, and rhizosphere bacterial richness and diversity, while reduced plant number and bacterial network stability of K. humilis. The NO3--N, K+, and Cl- concentrations were lower under grazing compared to GE. SG reduced the concentration of NH4+-N, TN, K+, and Na+ compared to YG. Moderate grazing intensity had a lower relative abundance of the r-strategists (Bacteroidota and Gammaproteobacteria) with higher bacterial network stability. Yak and sheep grazing showed reversed impacts on the bacterial network stability between the phyllosphere and rhizosphere of K. humilis. Proteobacteria and Actinobacteriota were identified in the molecular ecological network analysis as keystone taxa in the phyllosphere and rhizosphere networks, respectively, under all treatments. This study explained why sheep grazing has more adverse effects on grazing-tolerant grass species, K. humilis, than yak grazing, and will contribute to a better understanding of the impacts of different grazing practices and grazing enclosure on alpine grassland ecosystems on the QTP.
Palavras-chave
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Ecossistema
/
Carex (Planta)
Limite:
Animals
País/Região como assunto:
Asia
Idioma:
En
Revista:
Sci Total Environ
Ano de publicação:
2023
Tipo de documento:
Article