Spatial pattern of soil moisture at the cropland-grassland boundary in agro-pastoral transitional zone of North China
Wang, H.-M.; Wang, K.; Mi, J.; Xie, Y.-Z.
Ying Yong Sheng Tai Xue Bao 21(3): 604-612
2010
ISSN/ISBN: 1001-9332 PMID: 20560314 Document Number: 640740
By the methods of classic statistics and geostatistics, this paper analyzed the spatial heterogeneity of soil moisture at 0-50 cm depth in different sampling grain sizes (1 m x 1 m and 2 m x 2 m) at the cropland-grassland boundary in agro-pastoral transitional zone of North China. In study area, the soil moisture at 0-10 cm, 10-20 cm, 20-30 cm, 30-40 cm, and 40-50 cm depths of cropland, grassland, and cropland-grassland boundary presented moderate variance, and the coefficient of variation (CV) of grassland was higher than that of cropland. The CV increased with soil depth, and a significant linear regression relation (P < 0.05) was observed between them in sampling grain size 1 m x 1 m. In sampling grain size 1 m x 1 m, the spatial heterogeneity of soil moisture at different depths was obviously higher at cropland-grassland boundary than in cropland and grassland, which had a moderate to strong spatial dependency, and the range (A0) was 7.65-30.99 m; whereas in sampling grain size 2 m x 2 m, the spatial distribution of soil moisture at cropland-grassland boundary had both the moderate to strong spatial dependency and the pure nugget effect, and the A0 was 4.16-18.86 m, suggesting that there existed ecological edge effect of soil moisture at cropland-grassland boundary.