水保所知识产出(1956---)知识库

The vegetation growth of the Loess Plateau is often restricted by water, which seri-
ously threatens the water sustainability of regional ecosystem. In order to clarify the
relationship between supply and demand of vegetation water use after Grain for
Green Project, this study selected Malian River Basin as the research area and calcu-
lated the vegetation water use and water demand using the eco-hydrological model.
The results showed that the annual water demand of the basin was 570 mm, while
the average annual water supply was only 294 mm, accounting only for 52.0% of the
demand. From 2000 to 2018, the temporal and spatial matching degree of water sup-
ply and demand in the Malian River Basin were 0.63 and 0.65, respectively. On the
whole, the water resources in Malian River Basin can basically support the growth of
vegetation, but in some areas are not sustainable. Water resources in the southern
region can only barely maintain the normal growth of vegetation under the current
conditions, so it is not recommended to carry out new plantation in this area. The
evaluation of matching degree in the northern from January to April is poor, so it is
necessary to appropriately reduce the planting area of economic crops and replace it
with planting herbaceous plants with small water consumption in Spring. Compared
with the current conditions, under the future climate scenarios of ssp126 and
ssp585, the Malian River Basin will show a trend of warming and humidification. The
temporal matching degree of water supply and demand also significantly improved to
0.83 and 0.92, indicating that even if the planting structure did not change signifi-
cantly, water supply would gradually meet the needs of vegetation. The study results
can provide the basis for formulating more scientific and reasonable vegetation resto-
ration policies.