## 5 Conclusions
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* [PERSON] et al. (2019) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; et al. Relationship between gross primary production and canopy colour indices from digital camera images in a rubber (Hevea brasiliensis) plantation, Southwest China. _Forest. Ecol. Manag._**2019**, _437_, 222-231. [CrossRef]
* [PERSON] et al. (2002) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] User's Guide GPP and NPP (MOD17A2/A3) Products NASA MODIS Land Algorithm, Version 2.0. 2002. Available online: [[http://www.ntsg.umt.edu/modis/MOD17](http://www.ntsg.umt.edu/modis/MOD17) UsersGuide.pdf]([http://www.ntsg.umt.edu/modis/MOD17](http://www.ntsg.umt.edu/modis/MOD17) UsersGuide.pdf) (accessed on 24 December 2008). * [PERSON] et al. (2019) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Seasonal and interannual variations in carbon fluxes in East Asia semi-arid grasslands. _Sci. Total Environ._**2019**, _668_, 1128-1138. [CrossRef] [PubMed]
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