Potential impact of land-use change on habitat quality in the distribution range of crocodile lizards in China.

The over-exploitation of land resources poses a serious threat to biodiversity on a global scale. Changes in land-use and human exploitation have had a major impact on wild populations and their habitat in China. We assessed how habitat quality has changed over time (1995-2020). Specifically, we analyzed how the habitat quality of crocodile lizard has changed over time based on multi-temporal land-use data (1995, 2000, 2010, 2015 and 2020) using a land-use transfer matrix and habitat quality model. The results showed that the main landscape types in the study area were arable land (21.21% of the area) and woodland (69.59% of the area) during the period. Construction land (land used for development) had decreased by 991 km, a decrease rate of 59.84% from 1995 to 2000, and increased to 2349 km, an increase rate of 71.69% from 2000 to 2020. The proportion of grasslands and areas with water were negligible and overall, did not vary significantly in size over the study period. The main feature of land use change in the study area was the loss of grasslands and woodlands through development. The habitat quality model indicated that habitat quality was highest and degradation was lowest in Dayao mountain, Guxiu town, Qichong village and Beituo town. Habitat quality improved in Daguishan and Luokeng areas. Habitat quality was good in Daping mountain and Linzhouding, but they were highly fragmented with patches of low-quality habitat of varying sizes. Habitats were severely degraded in the Dateng Gorge area. The rate of habitat degradation has slowed over time in the study area, but gradually increased in degradation intensity, and low-quality habitats were widely distributed and overlapped with the crocodile lizards distribution area. We recommend that protected areas for the crocodile lizard be more closely monitored and managed to halt further decline in habitat quality.