关键词: 根系, 觅食反应, 土壤养分, 空间异质性

Abstract: Taking the Jingyue Development District of Changchun as a case, an integrated ecological risk index was built based on the landscape structure and the feature of land-use/land-cover obtained from SPOT 5 remote sensing image. Semivariogram analysis and block Kriging interpolation were conducted to get the distribution map of ecological risk. The results showed that the spatial distribution of ecological risk had a significant regional variation, and the ological risk was higher in middle area than in peripheral area. The analysis by verlaying with DEM data suggested that the ecological risk index was negatively orrelated with elevation, and the higher ecological risk covered nearly 96% of all higher ecological risk region when the altitude was lower than 300 m. Higher ecological risk was mainly distributed in the west of Jingyue Development District between Changshuang Highway and Changyi Highway, the key construction region with low elevation and vigorous economy. Ecological protection should be urgently adopted in this area.

Key words: Fine root, Foraging behavior, Soil nutrients, Spatial heterogeneity