Abstract: Grassland is one of the most widely distributed vegetation types in the world. A precise definition of the grassland boundary is essential for grassland resources research and management. We assessed the boundary accuracy of grassland in northern China, where was characterized by the most concentrated distribution of grassland in China. Based on the grassland sampling point data obtained from field survey, seven kinds of land use/cover data were examined, including the 30m globalland cover data (GlobeLand30), 1∶1000000 grassland resource map (GLT80s), remote sensing monitoring data of land use status in China (LUCC2010), multi-source integrated Chinese land cover map (MICLCover), GlobCover land cover map (Globcover2009), global land use data (GLC2000), and MODIS land cover data (MCD12Q1). The results showed that GLT80s had the largest area of grassland in northern China and was the most consistent with the other six land use/cover data. GLT80s also had the highest accuracy through sampling point verification, with a value of 88.32%. Globcover2009 had the lowest accuracy, with a value of 29.31%. The accuracy of MCD12Q1 and GLC2000 was 83.74% and 83.45%, respectively. The values of other three land use/cover data ranged from 73.42% to 78.97%. Results of statistical analysis for different provinces showed that MCD12Q1 in Qinghai had the highest accuracy(94.23%), and the accuracy of GLC2000 and GlobeLand30 was also above 90% respectively. However, GLT80s always had the highest accuracy in other provinces, including Xinjiang, Tibet, Inner Mongolia, and Gansu. The main reason for the difference of grassland distribution between GLT80s and other data was that the temperate desert grassland in GLT80s was generally classified as bare ground in other data, which occupied 22.59%-42.87% of the total inconsistent distribution area. Therefore, we suggested that MCD12Q1 should be given preference in Qinghai for assessing the grassland resources and function, while GLT80s should be selected in other provinces, but special attention should be paid to the accuracy of its division in temperate desert grassland.

Key words: wood-decaying fungi, fungal flora, ecological distribution, functional trait