## 4 Discussion  
### Possible Reasons for T\({}_{\text{min}}\) in Determining Plant Growth over the TP  
The TP is a sensitive and early-warning area of global warming. Numerous studies have shown that climate warming has resulted in the overall growth in vegetation on the TP as well as the earlier start of the growing season for the vegetation during the \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{2}{c}{\(q\)**Statistic**} & \multicolumn{2}{c}{**Unfrozen Ground**} & \multicolumn{2}{c}{**Seasonal Frozen Ground**} & \multicolumn{1}{c}{**Permafrost**} \\ \hline \multirow{2}{*}{T\({}_{\text{min}}\)} & NDVI & 0.48 ** & 0.56 ** & 0.53 ** \\  & GPP & 0.21 * & 0.44 ** & 0.36 ** \\ \hline \multirow{2}{*}{T\({}_{\text{max}}\)} & NDVI & 0.34 ** & 0.49 ** & 0.40 ** \\  & GPP & 0.16 & 0.35 ** & 0.34 ** \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Temperature determinants affect the spatial patterns of NDVI and GPP in different frozen regions, determined by the \(q\) value. The \(q\) value less than 0.05 represents significance (95% confidence is denoted by *, 99% confidence is denoted by **). Figure 8: The frequency distributions of the corresponding contributions of which the values were indicated by the map legend on (**a**) NDVI and (**b**) GPP based on the Standardized Multivariate Linear Regression (SMLR) method. past decades [38; 39], and have also unequivocally shown that temperature is the primary driving force of vegetation growth on the TP [40]. The results of this study demonstrate a significant growth trend in NDVI over the past 40 years, as well as a significant rising trend in both \(T_{\text{min}}\) and \(T_{\text{max}}\) during the growing season. These trends have resulted in a significant decrease in \(T_{\text{D}}\), which is well in line with the findings of previous studies [41]. The reduction in the diurnal temperature range is caused by the fact that temperature varies more rapidly at night than during the day. Previous studies have revealed that the growth rate of \(T_{\text{min}}\) is significantly faster than that of \(T_{\text{max}}\)[42]. Moreover, since photosynthesis in most plants primarily occurs during the day while respiration continues throughout the day and night, this asymmetrical warming will inevitably impact the carbon uptake and consumption of vegetation [43]. A comparison of the findings with those of other studies confirms that \(T_{\text{min}}\) has a stronger effect on plant growth than \(T_{\text{max}}\)[17]. There could be several reasons for this, including the fact that higher \(T_{\text{min}}\) may help to reduce frost damage, as suggested by [PERSON] et al. [44] To be more specific, during the growing season, \(T_{\text{min}}\) is typically below 0 \({}^{\circ}C\), except in unfrozen regions on the TP (Figures 3a and 5), which may limit the growth processes of the plants [45]. To reduce the risk of freezing damage, plants may slow or postpone their growth [46]. Faster growing nighttime temperatures enable plants to consume more carbohydrates at night, which stimulates an increase in photosynthesis over the next few days [16; 47]. Therefore, rising nighttime temperatures could potentially alleviate these limitations and reduce the risk of freezing injury, which may promote vegetation and leaf development during the growing season. Additionally, the absorption of soil water is heavily dependent on the thawing of the soil during early spring on the TP. The vegetation of the TP is mainly dominated by alpine meadows and alpine grasslands. The growth of this vegetation during spring is limited by low water utilization efficiency [48]. Minimum soil temperature controls the amount of spring soil water available [49; 50; 51]. Moreover, nighttime warming stimulates carbon sequestration, enhancing the community's resistance to drought and potentially promoting ecosystem sustainability [52]. However, \(T_{\text{min}}\) also has inhibitory effects on vegetation growth around 13% of the TP, mainly located in the northern and southern edges.