Figure 1.
Tick life stages and their relations to host types.
Solid boxes indicate populations stated in the CA model. Solid arrows indicate the development of tick populations. Dashed lines show attachment relations. Two phases, questing and feeding, were stated for each post egg life stage. Host preferences of questing ticks differ between life stages. In the model, it was assumed that larvae feed on small-sized animals, adults feed on large-sized animals, and nymphs feed on both.
Table 1.
Parameters used in the model.
Figure 2.
Land cover map of the study areas of Misonne et al.
[38]. Light green: grassland; dark green: woodland; white: no or sparse vegetation. Study sites are tagged with coordinates (military grid reference system) and pointed to the corresponding site maps and site names. The size of cell is 1 ha. Highlighted zones in site maps refer to the sample blocks.
Figure 3.
Examples of landscapes fragmented in different scenarios.
Green cells refer to woodland areas. White cells refer to non-vegetated areas in situation I and grassland areas in situation II. The dimension of each landscape is 50×50 cells and the size of cell is 1 ha.
Figure 4.
Bar chart indicates the value of sensitivity index (S) on Lyme disease risk indices examined for each parameter. Black, red and blue bars refer to S values on density of nymphs (DON), nymphal infection prevalence (NIP), and density of infectious nymphs (DIN) respectively.
Figure 5.
The effects of woodland coverage on densities of nymphs.
Figure shows boxplots of densities of nymphs (DON) in woodland categorised by woodland percentages in situation I and II. The lower and upper boundaries of box refer to the 1st and 3rd quartiles of DON in each category. Crosses indicate the median value of DON. The whiskers refer to maximum and minimum DON values in each category. Red lines are two linear functions of woodland percentage categories on the median value of DON in situation I: (a) DON = −49 * woodland percentage categories +65973, R2 = 0.92; and in situation II: DON = −65 * woodland percentage categories +66009, R2 = 0.70.
Figure 6.
Density of infectious nymphs under different landscape fragmentation scenarios.
Figure shows the simulated density of infectious nymphs (DIN) in woodland for landscapes with different woodland percentages and block sizes in the two situations.
Figure 7.
The effects of woodland aggregation index on densities of infectious nymphs.
Red lines indicate two linear functions of aggregation index (AI) on the simulated densities of infectious nymphs (DIN) in woodland of: (i) DIN = −170 * AI +34745 in situation I, R2 = 0.96; and (ii) DIN = 124 * AI+3031, R2 = 0.95 in situation II.