How are the distribution patterns and conservation planning of woody species diversity in Xinjiang?

Patterns of plant species diversity have long been of interest to ecologists. Due to loss of biodiversity caused by human activities, the topic of plant species diversity has become more and more important. Biodiversity loss has a negative effect on ecosystem function. Therefore, quantitative data on distribution patterns of plant species diversity is necessary for conservation planning and sustainable utilization especially in arid and semi-arid regions.

Prof. ZHANG Mingli and ZHANG Hongxiang selected the Xinjiang as the study area to investigate the patterns of woody species diversity and their relationships with environmental factors. A total of 133 woody forest species and 220 woody xerophytic species were sampled in this study. The current and last glacial maximum (LGM) distributions of these species were modeled by using the method of species distribution modeling (SDM).

Values of species diversity were divided into four levels for both woody forest species and woody xerophytic species. Three diversity hotspots for forest species were identified, including the Central Tianshan Mountains around the Ili Valley, the Western Dzungarian Mountains, and the western portion of the Altai Mountains. There was a significant correlation between the forest species diversity and precipitation. According to the LGM distribution model, only a total of 53 forest species showed LGM distributions in Xinjiang. For forest species, there were three refugial regions in Xinjiang, i.e. the Central Tianshan Mountains around the Ili Valley, the Western Dzungarian Mountains, and the western part of Altai Mountains.

The Dzungarian Basin, the Ili Valley, and the western and northern margins of the Tarim Basin along the Tianshan Mountains possessed the higher species diversity of xerophytes. Xerophytes species diversity was significantly correlated with the precipitation and temperature. According to the LGM distribution model, a total of 92 xerophytes species showed LGM distributions in Xinjiang and the areas with higher numbers of plant species were mainly distributed in the Dzungarian Basin, the Ili Valley, and the Pamirs.

This study also showed that most areas of Xinjiang with high levels of species richness did not need prior protection, but Barluk Mountains and Tarbagatai Mountains, the Pamir Plateau, and the Southern part of Yiwu County in eastern Xinjiang should be protected urgently. This research was published in Biological Conservation in September 2014.