## 3 Results
### ET Simulation Results Based on the PT-JPL Model  
Figure 7 shows the trend slope and significance test results for the actual ET, Et, Es, and Ei in the HLS from 2000 to 2018 based on the PT-JPL model simulation under the actual vegetation restoration scenario. It can be seen that ET, Es, and Ei showed different degrees of an increasing trend (Figure 6a-d) in 2000-2018, except for the decreasing trend in Et in the HLS. Among them, ET showed an increasing trend in the northern and central regions of the HLS (72.4%), while the southern and northeastern regions (27.2%) showed a decreasing trend (Figure 7e). Regarding Et, 80.4% showed a decreasing trend, and a few areas in the central region showed an increasing trend (Figure 7f). Ei exhibited a rising trend in the northern region of the HLS and a notably declining trend in the southern region, while the central region experienced a significant upward trend in most areas (Figure 7g). Meanwhile, Es showed a marked increase across the majority of the HLS (83.4%), representing the most substantial growth among the various ET types (Figure 7h).  
Under the scenario of vegetation remaining unchanged (Figure 8), different components of ET showed significant spatial heterogeneity. From 2000 to 2018, ET, Et, Es, and Ei in the HLS showed a similar trend; that is, the northern and southern parts of the study area decreased, and the central part increased. Specifically, ET showed an increasing trend in the northern and central regions of the HLS (62.0%), while the southern and northeastern regions (37.7%) showed a decreasing trend (Figure 8e). From 2000 to 2018, the trend of increase or decrease of Et in the HLS was very significant. The area with a significant increase (59.0%) was distributed in the middle, while the north and south showed a significant decrease (37.5%). The variation trend in intercepted evaporation (Ei) in different regions is more complex. The south mainly shows a decrease (34.8%), the middle shows a significant increase and a slight increase (64.8%), and the northern region shows a slight decrease. The increase or decrease in soil evaporation (Es) in most areas of the HLS was not significant. Only the central part showed a significant increase (13.6%), the southern region showed a slight decrease, and the rest showed a slight increase (59.2%).  
Figure 6: The interannual variation trends in NDVI and LAI in the HLS from 2000 to 2018. (**a**,**b**) The temporal and spatial variation trend in NDVI and LAI from 2000 to 2018. (**c**,**d**) The significance of the changes in NDVI and LAI from 2000 to 2018. (**e**,**f**) The average annual sequence values of NDVI and LAI from 2000 to 2018.  
Figure 8: Slope of ET (**a**), Et (**b**), Ei (**c**), and Es (**d**) and the significance test of the slope of ET (**e**), Et (**f**), Ei (**g**), and Es (**h**) in the HLS from 2000 to 2018 under the condition of constant vegetation control simulated by PT-JPL.  
Figure 7: Slope of ET (**a**), Et (**b**), Ei (**c**), and Es (**d**) and the significance test of the slope of ET (**e**), Et (**f**), Ei (**g**), and Es (**h**) in the HLS from 2000 to 2018 under the vegetation change scenario simulated by PT-JPL.