Spatial Modelling of Small Mammal Distributions in Relation to Parasite Transmission and Long-Term Landscape Change in Western China

摘要

This research investigates the spatial distributions of Ochotona, an intermediate host vector for the parasitic tapeworm Echinococcus multilocularis which causes a significant burden of human disease in western China. Ochotona distributions are modelled in relation to landscape characteristics derived from Landsat TM and ETM+ imagery. Statistical models identify the landscape variables influencing Ochotona spatial distributions, describe the nature of these relationships, and predict probable Ochotona distributions over large areas. Assessment of landscape change over a twenty-four year period, and its impact on Ochotona communities was also modelled. Results indicate that Ochotona distributions are significantly related to the distribution of the degraded grassland habitat. Results also showed that large-scale landscape degradation has occurred at the study site between 1977 and 2001, increasing the area of degraded grassland, and the probability of Ochotona presence. Probability maps of Ochotona distributions are produced, with potentially significant applications in the development of future disease control programmes.