## 5 Conclusions  
In this study, we used tower-based SIF, satellite-derived SIF and eddy covariance GPP data from two continuous growing seasons to investigate the difference between the responses of GPP and SIF to the environmental variables, including radiation, air temperature, and EF, based on the binning method. The conclusions are as follows:  
1. GPP and SIF had similar light response trends, which both increased with increasing radiation, while the rates of increases in GPP and SIF exhibited divergence related to air temperature and water availability. When Ta and EF values were lower, SIF increased faster than GPP. With the increase in Ta and EF, the difference between the increase rates of GPP and SIF gradually reduced.
2. The GPP-SIF relationship was decoupled when the environment was not suitable for vegetation growth, and the correlation between GPP and SIF was gradually improved with increasing Ta and EF.
3. The slope of the GPP-SIF relationship was mainly affected by Ta and EF, which increased with increasing EF and Ta.  
**Supplementary Materials:** The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app14020771/s1](https://www.mdpi.com/article/10.3390/app14020771/s1)]([https://www.mdpi.com/article/10.3390/app14020771/s1](https://www.mdpi.com/article/10.3390/app14020771/s1)), Figure S1: The comparison of the half-hourly responses of GPP and SIF to PAR under different EF bins.; Figure S2: The responses of daily SIF (a) and GPP (b) to the PAR under different EF bins.; Figure S3: The comparison of half-hourly responses of GPP and SIF to PAR under different Ta bins.; Figure S4: The responses of daily SIF (a) and GPP (b) to the PAR under different Ta bins.  
**Author Contributions:** Conceptualization, J.B. and R.S.; methodology, J.B., H.Z. and R.S.; software, J.B. and H.Z.; validation, J.B., H.Z. and R.S.; formal analysis, J.B. and H.Z.; investigation, J.B. and H.Z.; resources, J.B.; data curation, X.L. and L.L.; writing--original draft preparation, J.B.; writing--review and editing, J.B., R.S., X.L. and L.L.; visualization, J.B.; supervision, R.S.; project administration, R.S.; funding acquisition, R.S. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded by the National Natural Science Foundation of China, grant number: 42271330.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** Dataset available on request from the authors.  
**Acknowledgments:** We thank [PERSON] et al. for sharing eddy covariance data at DM site (data accessed on 22 May 2022) ([[https://data.tpdc.ac.cn/en/](https://data.tpdc.ac.cn/en/)]([https://data.tpdc.ac.cn/en/](https://data.tpdc.ac.cn/en/))). We also thank the hard work of [PERSON] et al. for producing the TROPOMI SIF and sharing this dataset ([[https://s5p-troposif.noveltis.fr/data-access/](https://s5p-troposif.noveltis.fr/data-access/)]([https://s5p-troposif.noveltis.fr/data-access/](https://s5p-troposif.noveltis.fr/data-access/))). This study also used the eddy covariance data acquired by the AmeriFlux, we sincerely thank all AmeriFlux communities of the eddy covariance data ([[https://ameriflux.lbl.gov/](https://ameriflux.lbl.gov/)]([https://ameriflux.lbl.gov/](https://ameriflux.lbl.gov/))).  
**Conflicts of Interest:** The authors declare no conflict of interest.