Dynamics of landscape pattern and connectivity of wetlands in western Jilin Province, China

The Interconnected River System Network plan as an important target for river health and enhancing water resource utilization was put forward in the new period in China. This study aimed at analyzing and interpreting changes in landscape pattern and connectivity of wetlands in 1950s, 1980s and 2012 in western Jilin Province using FRAGSTATS and conefor software. The results showed that the appropriate grain size of wetlands landscape pattern analysis was 900 m, and the total area, connectance index, aggregation index, patch cohesion index (COHESION) all showed a sharp decrease from 1950s to 2012, while the patch density increased largely. The appropriate distance thresholds of the wetland landscape connectivity were 4000 m for sub-region I and 7000 m for sub-region II, III, IV. The landscape connectivity also decreased significantly from 1950s to 2012, which was especially obvious in sub-region I from 1950s to 1980s and sub-region II from 1980s to 2012. The area and number of important patches for landscape connectivity (dPC > 1) declined significantly from 1950s to 2012. And the restoration of the important patches (dPC > 1) was critical for the wetlands landscape connectivity improvement. The correlation results between landscape pattern metrics and connectivity indexes indicated that PC had a significant positive relationship with COHESION, and dPC had a strong significant positive relationship with AREA, PERIM, while a negative correlation with PAR.