5. Conclusion
GE significantly increased the
aboveground biomass and root biomass compared to that observed after
implementing different grazing methods. Meanwhile, the R/S ratio of GE
was higher than that of MG and RG and lower than that of CG. The SOC
content of GE was higher than that associated with grazing methods at
soil depths of 0–40 cm, while being significantly higher at 0–10 and
20–30 cm; however, the TN content was lower than that observed after
implementing the grazing methods, exhibiting a significant decrease when
compared to that obtained with CG and RG. GE significantly increased the
C/N and C/P ratios at each soil depth and N/P ratio in the topsoil
layer. GE significantly increased the ecosystem organic carbon stocks
(EOCs) and decreased the ecosystem total nitrogen stocks (ETNs), with
the EOCs being 22.29% (MG) and 16.31% (RG) higher and the ETNs being
7.76% (RG) higher than those obtained with CG. There was a significant
positive relationship between EOSs and
SOC, C/N, C/P, N/P, and aboveground
biomass, and a negative relationship with TP; the ETNs were positively
correlated with N and P and negatively correlated with C/N, C/P,
aboveground biomass, and root biomass. These results indicate that GE
can provide significant improvements in plant recovery and ecosystem
organic carbon storage, whereas RG is beneficial for promoting both EOCs
and ETNs in karst grasslands.