Grazing exclusion has been widely used to restore the degraded alpine grasslands on the Qinghai-Tibetan Plateau (QTP). However, the dynamics of soil organic carbon (SOC) and soil total nitrogen (STN) pools after grazing exclusion and their controlling factors are currently less understood in this region. Here, a meta-analysis was conducted to quantitatively assess the changes in SOC and STN stocks in topsoil (0–30 cm) following grazing exclusion in three major grassland types (alpine meadow, alpine steppe, and alpine desert steppe) on the QTP and to explore the potential factors controlling the effects of grazing exclusion on SOC and STN stocks. The results showed that overall, grazing exclusion significantly increased SOC stock by 16.5% and STN stock by 11.2%. Significant increases in both SOC and STN stocks were observed after grazing exclusion of alpine meadow. In contrast, grazing exclusion did not improve SOC and STN stocks in the other two grassland types. The difference in mean annual precipitation among grassland types was a likely reason for the different dynamics of SOC and STN stocks after grazing exclusion. The effect sizes of both SOC and STN stocks were positively related to the duration of grazing exclusion, and a positive relationship was detected between the effect size of SOC stock and that of STN stock, demonstrating that the dynamics of SOC and STN were closely coupled during the period of grazing exclusion. However, grazing exclusion had no impact on soil C:N ratio for all grassland types, indicating that soil C:N ratio was generally stable after grazing exclusion. Therefore, it is suggested that the increase in STN can support continuous SOC accumulation following grazing exclusion. In conclusion, the findings suggest that the effects of grazing exclusion on SOC and STN stocks differ among grassland types on the QTP, and grazing exclusion of alpine meadows may provide substantial opportunities for improving SOC and STN stocks in this region.

(1) Background: This study aimed to evaluate the effects of organic fertilizer dose on soil nutrients, wolfberry fruit nutrient compositions, and fruit yields. (2) Methods: We conducted a two-year field trial in two typical fields with different fertility levels in the Qaidam area. Six treatments were applied to each field, including CK, M2 M4, M6, M8, and M10 (representing 0, 2, 4, 6, 8, and 10 kg organic fertilizer/plant, respectively) in the high-fertility field and CK, M3, M6, M9, M12, and M15 (representing 0, 3, 6, 9, 12, and 15 kg organic fertilizer/plant, respectively) in the low-fertility field. An ANOVA was used to determine the significant difference between treatments, and the LSD method was used for multiple comparisons of analysis of variance. (3) Results: In the high-fertility field, the application of organic fertilizer significantly affected the total nitrogen (N) content, mineral N storage, and soil organic matter content. The application of too much organic fertilizer significantly increased the soil’s EC value. In the low-fertility field, the effect of organic fertilizer application on soil nutrient enhancement differed significantly among soil layers but significantly increased the contents of total phenols, flavonoids, and amino acids in wolfberry fruit, and there was a significant trend of increasing wolfberry yield with increasing organic fertilizer application. (4) Conclusions: In the Qaidam area of the Tibetan Plateau, it is recommended to apply 2–4 kg commercial organic fertilizer/plant in the high-fertility wolfberry orchards while 9–12 kg in the low-fertility wolfberry orchards is recommended.