Niche study on ticks in the Tarim Basin.

Objective To grasp the niche breadth and overlap of ticks in the Tarim Basin,to research the effect of ticks in the area on tick-borne natural focal diseases from the view of tick ecology.Methods On the basis of cluster analysis of tick community in the area,the niche breadth index formula of hannon-Wiener and niche overlap formula of Pianka(1973)were taken to calculate the niche breadth and niche overlap index of ticks.Results The niche breadth of Hyalomma asiaticum asiaticum and Hyalomma asiaticum kozlovi was the biggest as 0.525 7 and 0.468,respectively,the next were Rhipicephalus turanicus(0.379)and Dermacentor niveus(0.299)with the least of Rhipicephalus sanguineus(0).The biggest niche overlap was among Rhipicephalus turanicus,Dermacentor niveus and Rhipicephalus sanguineus over 0.9,the next was 0.347 9 between two species of Hyalomma.The niche overlap values were 0.238 7 between Hyalomma asiaticum asiaticum and Dermacentor niveus,0.161 7 between Hyalomma asiaticum kozlovi and Rhipicephalus turanicus.The niche overlap value was less than 0.1 among Hyalomma asiaticum asiaticum and two species of Rhipicephalus.Conclusions Hyalomma asiaticum asiaticum and Hyalomma asiaticum kozlovi are very important for ticks in the Tarim Basin,with the separation of habitat distribution.