Objective Ecological security pattern can provide important basis for optimizing various elements of ecological system and improving regional ecological security.

Method In this paper, four important ecosystem service functions, i.e., carbon sequestration, habitat quality, soil conservation, and water conservation were calculated using the InVEST model in the Xiaoluanhe River Basin of Weichang County, Hebei Province of northern China. And a comprehensive evaluation of ecosystem service functions in the region was carried out. The minimum cumulative resistance (MCR) model was used to construct ecological corridors in this area.

Result Within the region, 14 ecological sources were identified, and 34 ecological corridors were constructed, of which 19 were of high importance. Comprehensive ecological service function and the spatial distribution pattern of ecological source in the south, middle and north parts of the Xiaoluanhe River Basin in Weichang County were significantly different. The forest area in the southern mountainous area was large, the comprehensive ecosystem service function was high, and the ecological corridor network was dense. The human disturbance in the central agricultural and pastoral areas was serious, which had hindered the ecological processes between the south and north. In the northern area near the Saihanba Forest Farm, four important ecosystem service functions were relatively high, and there were some large ecological sources, and the importance of ecological corridors was high. The overall ecological connectivity of the Xiaoluan River Basin was not high. Apart from the river itself, the only ecological corridor connecting the south and north was located on the eastern edge of the basin, which plays an important role in the regional security pattern.

Conclusion The ecosystem service function and ecological security pattern of the southern, central and northern areas of the Xiaoluanhe River Basin in Weichang County differ greatly, and the security pattern constructed can provide theoretical reference for formulating appropriate ecological conservation and restoration strategies in each part of the region.