# A Digital Framework to Predict the Sunshine Requirements of Landscape Plants
## 3 Results and Discussion
### Accuracy Analysis of the Forecasting Framework  
In order to verify the accuracy of the digital forecasting framework, the LI-6400 XT Portable Photosynthetic System was used for the field measurement of photosynthetic rate (Pn)-PAR response curves, and to obtain the values of LCP and LSP based on the different photosynthetic intensity settings of the red/blue LED light source, from 0 to 2000 umol/m\({}^{2}\)-s. Our results show that the healthy level is higher than LCP, which are both much lower than LSP. However, the sub-healthy level is the survival line for landscape plants, which is more valuable for adaptive plant selection in practice. In addition, we cannot obtain the LCP and LSP data of _Zoysia matrella_ ([PERSON] through the LI-6400 XT, due to the fact that the leaves are too small to be measured by the needle chamber (2 \(\times\) 6 cm). Our research indicates that the sub-healthy and healthy levels of _Zoysia matrella_ ([PERSON] [PERSON] are higher (Figure 6). Therefore, this plant belongs to the sun-loving plant species, although some cultivars of zoysia grass have reported differences within a certain range of shading [78; 79].  
The sub-healthy level is higher than the healthy level for _Aspidistra elatior_ [PERSON], which is able to tolerate extreme shading, even in a 6 umol/m\({}^{2}\)-s PPF environment. Many studies have confirmed that the biomass of this species can be increased by reducing solar radiation [75; 76; 77], so it belongs to the shade-loving plant species. It is noteworthy that LCP is higher than the sub-healthy level for _Cercis chinensis_ [PERSON] in Figure 6. The results reported by other scholars suggest that the LCP of this species is 31.98 umol/m\({}^{2}\)-s [46]. From this, we can see that both the accuracy and stability of the LI-6400 XT are greatly affected by the environment and the operator. Detailed comparison data are listed in Table 5. In addition, we found that the growth of _Euonymous japonicus_ var. alba-mariata T. [PERSON] was poorer than that of _Euonymous japonicus_ (original species) at a PPF of 65 umol/m\({}^{2}\)-s, and its sub-healthy and healthy levels are also higher than the original species, so we conclude that the lower chlorophyll content of the variegated leaf variety results in a decrease in its photosynthetic capacity [80; 81]. Overall, our forecasting framework is relatively robust and can be used as an effective tool for the assessment of the solar radiation response of landscape plants.  
Because of the ecological factors that affect plant health are diverse and can play a synergistic role. In this study, in order to verify the stability and reliability of our results, a comparison of the research is shown in Table 5, between our research and the results  
Figure 6: Numerical comparison between LCP-LSP and the sub-healthy and healthy levels, as measured by LI-6400 XT and forecast by our digital framework, respectively.  
of others. The distribution of these experimental sites is located in the cities of Wuhan, Changsha, Nanjing and Chongqing, respectively. They have similar geographic latitudes and are used to eliminate interference from climatic and soil factors. The results show that the healthy level is much higher than the value of LCP, the sub-healthy level is also almost higher than the LCP, except _Nandina domestica_ [PERSON] and _Mahonia fortunei_ ([PERSON].) [PERSON]. In our research, it is found that the solar radiation of the planting site should meet the healthy level of landscape plants, so that its ecological functions and artistic effects can be better exerted. In practice, the value of healthy level can be converted into the percentage of total solar radiation, combined with GIS spatial analysis and the landscape plant database, techniques to achieve the goal of \"right tree, right place\" in future research. In contrast, the LCP and LSP data lack the practical values in the digital process of plant species selection and configuration for landscape architects.