Ecosystem services assessments determine regional sustainable development and are critical to human well-being. This study took the Loess Plateau as the research area

based on the CASA

InVEST and RUSLE model

combined with the data of land use types

normalized vegetation index

meteorology and so on

analyzed the spatial and temporal distribution characteristics of the three key ecosystem services (NPP

soil conservation

and water conservation) in 2000

2005

2010 and 2015; and identified the hot spots of three ecosystem services

analyzed the trade-offs between different ecosystem services on the Loess Plateau and different climatic regions (arid

semi-arid

plateau and semi-humid climate zone) based on the correlation coefficient method. The results showed: (1) From 2000 to 2015

land use types in the Loess Plateau region changed drastically

among which forest land (2.8%) and construction land (43.1%) increased significantly

and cultivated land (-2.7%) decreased significantly. (2) From 2000 to 2015

all the average unit area of net primary productivity (NPP)

water conservation and soil conservation showed an increasing trend

increased by 14.1%

5.3% and 101.3% respectively. (3) The areas occupied by the four types of hotspots in the Loess Plateau (non-hotspots

first-type hotspots

second-type hotspots

and third-type hotspots) had not changed significantly

but the distribution had the obvious zonal distribution

that was non-hotspots

first-class hotspots

second-class hotspots

and third-class hot spots respectively from northwest to southeast. (4) Across the Loess Plateau

there was a synergistic relationship between soil conservation and NPP

soil conservation and water conservation. And there was a trade-off between NPP and water conservation. However

soil conservation and water conservation was trade-off in semi-arid and semi-humid regions

and the relationship between NPP and water conservation also was trade-off in arid and semi-arid regions. In order to promote the sustainable management of regional ecosystems

the relationships between ecosystem services should be considered in the land planning process

and trade-offs should be minimized and synergies should be maximized.