image: Spatial distribution map of (a) temperate savanna and (b–d) landscape photographs of various types of temperate savanna.
Credit: ©Science China Press
Savannas play a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon cycle. Mapping the spatial distribution and extent of existing temperate savannas is crucial for their conservation and utilization, as well as for managing and restoring the natural semi-arid ecosystems in northern China. A team of scientists from the Institute of Ecological Conservation and Restoration at the Chinese Academy of Forestry revealed the distribution and, for the first time, mapped the presence of temperate savannas in the sandy lands of eastern China. Their findings were published in SCIENCE CHINA Earth Sciences.
The high spatial heterogeneity induced by the mixed distribution of savanna trees and grasses has consistently posed challenges for remote sensing mapping of this type. The team proposed a new remote sensing mapping method for separating woody and herbaceous vegetation and estimating fractional cover using Random Forest algorithms by integrating very high-resolution UAV and satellite imagery. Temperate savannas in the sandy lands of eastern China were mapped, and spatial characteristics of geographical distribution, soil, and precipitation were explored in the Horqin and Otindag Sandy Lands of eastern China.
Temperate savannas are primarily found in northern Horqin Sandy Land, central and eastern Otindag Sandy Land, and the transitional zone from the southern slopes of the Greater Khingan Mountains to the plains, covering an area of 3.27 million hectares. The fractional woody vegetation cover ranged from 5% to 45%, whereas fractional herbaceous vegetation cover ranged from 30% to 85%. There are three types of temperate savanna: elm, maple/oak, and shrub savanna. Temperate savannas concentrate in areas with annual precipitation of 330-420 mm, with soil types predominantly being Arenosols, Chemozems, and Kastanozems.
This study provides precise information on the geographical distribution and extent of temperate savannas in the sandy lands of eastern China, supporting the conservation and utilization of temperate savanna ecosystems, as well as the prevention of desertification and ecological restoration in these regions. The research methodology offers new insights for global-scale fine classification mapping and dynamic change analysis of temperate savannas.
See the article:
Li X, Wang F, Duan T, Yang K, Yang B, Wang C, Tian X, Lu Q. 2025. Distribution and mapping of temperate savanna in the sandy lands of eastern China. Science China Earth Sciences, 68(1): 128-141, https://doi.org/10.1007/s11430-024-1449-y
Journal
Science China Earth Sciences