Analysis of Himalayan marmot distribution and plague risk in Qinghai province of China using the "3S" technology.

To provide guidance for plague surveillance and a reliable basis for plague prevention and control, we analyzed the habitat characteristics of Himalayan marmots, developed Himalayan marmot information collection system V3.0 based on global navigation satellite system (GNSS), remote sensing, and geographic information system ("3S") technology, and drew a predictive spatial distribution map of Himalayan marmots in Qinghai Province. Field survey data of 352 marmot plague sites in Qinghai Province were collected in 2014, and the data from 80 sample sites were included. The Himalayan marmot habitat characteristics were analyzed based on "3S" technology using five environment variables (elevation, slope, aspect, vegetation cover, and grass type) and the geographical coordinates. Himalayan marmot information collection system V3.0, which has been approved by the National Copyright Administration of the People's Republic of China (No.00764743), was used to draw a predictive spatial distribution map of Himalayan marmots in Qinghai province. Moreover, from 2015 to 2017, positioning data of the plague-foci and plague-free areas in Qinghai Province were collected using GNSS receptor for field validations to verify the accuracy of the marmot predictive spatial distribution map. Elevation, slope, vegetation cover, and grassland type were identified as important environmental factors that determine the spatial distribution of Himalayan marmots. The suitable range of environmental features was 3400-4600 m elevation, 5°-20° slope, 0.60-1.00 vegetation cover, and alpine meadows. The Himalayan marmot predictive spatial distribution map in Qinghai Province based on "3S" technology and marmot information collection system V3.0 had a spatial resolution of 30 m. Field validation in areas of Qinghai Province revealed a prediction accuracy and mean absolute error of 0.8669 and 0.1331, respectively, which indicated excellent prediction accuracy. This study greatly improved the work efficiency of plague surveillance and effectively reduced the work intensity of researchers. Application of "3S" technology and marmot information collection system V3.0 has improved the data collection efficiency, provided new technical means for plague investigation and research, and provided a reference for development of plague surveillance programs. The research results will play a positive role in promoting the improvement and perfection of plague prevention and control strategies in Qinghai province and even in China.