Potential suitable area and natural driving force of Artemisia desertorum shrub in Ulanbuh Desert of northwestern China

  Objective  By studying the changes of geographical distribution of typical desert species and their driving factors, we can provide scientific basis for the restoration of desert vegetation.

  Method  In this paper, Artemisia desertorum, the dominant plant in Ulanbuh Desert of northwestern China, was taken as the research object. The geographical distribution data of A. desertorum were collected and sorted out through field investigation and remote sensing image recognition. Combined with 29 environmental variables, the optimal species distribution model was obtained, and the optimal model was adopted. Based on the Noresm1-M climate model, the potential distribution of A. desertorum in different periods under two emission scenarios was predicted, and the threshold range of major environmental factors for its suitable distribution was analyzed, and the impact of future climate change on the potential geographical distribution of A. desertorum shrub was predicted, and it was divided into suitable distribution areas.

  Result  The maximum entropy (MaxEnt) model was the best one to simulate the geographical distribution of A. desertorum shrub. The annual average temperature was the determining factor of the geographical distribution of A. desertorum shrub. The suitable range of annual average temperature was 7.4−9.0 ℃, and the threshold was 8.4 ℃. The main natural driving factors were slope and average temperature in the wettest season, and temperature was more important than rainfall. In the 2050s, under RCP2.6 emission mode, the centroid of A. desertorum shrub will migrate 4.55 km to the southwest, and with the increase of CO₂ emission intensity, it will migrate 1.21 km northward. By the 2070s, the centroid of A. desertorum shrub will migrate 2.60 km to northeast under the RCP2.6 emission mode. With the increase of CO₂ emission intensity, it will turn to migrate 0.83 km northward. With the passage of time and the warming of climate, the suitable habitat of A. desertorum was continuously fragmented and the suitable habitat area was gradually reduced, and more suitable habitat was degraded to low or unsuitable habitat.

  Conclusion  With the shrink of A. desertorum’s most suitable area, the impact of climate change in Ulanbuh Desert on the distribution area of A. desertorum shrub should be closely observed, and the corresponding ecological restoration research should be carried out. At present, the high and moderate suitable areas should be actively planted with A. desertorum, and the unsuitable areas should actively develop other local vegetation under the premise of economic and technological feasibility, or improve their suitability by improving the sandy geology. Under the trend of future climate warming, ecological monitoring should be strengthened, and measures should be taken to actively respond to the changes in the distribution area, so as to improve the regional vegetation coverage and form a virtuous cycle, and finally achieve the goal of restoring desert vegetation, improving the stability of the ecosystem and giving full play to its ecological functions.