Fractal Analysis of Root Architecture Responses of Saussurea Salsa to Different Habitats in Sugan Lake Wetland on the Northern Margin of Qinghai-Tibet Plateau

Abstract

Aims The fractal structure is an important root architecture characteristic, which can reflect the plasticity mechanism and carbon consumption characteristics of root architecture in heterogeneous habitats. However, there are few studies on the root architecture of inland salt marsh plants from the perspective of fractal geometry. Methods This study according to the difference of the habitat conditions, setting plot I (the near water area, distance from the lakeshore, 50–200 m), plot II (the middle water area, distance from the lakeshore, 300–500 m), plot III (the distance water area, distance from the lakeshore, 600–800 m) 3 test sample. The Saussurea salsa as the research object, the root geometric morphology traits and the root fractal structure of Saussurea salsa in the Sugan Lake wetland was studied in response to heterogeneous habitats. Results The results showed that there was a highly significant negative correlation (p < 0.01) between FD and FA of Saussurea salsa at plot I and plot III, meanwhile, there appeared a less significant negative correlation (p < 0.05) between FD and FA at plot II. Conclusions With the habitat changed from plot I to plot III, the Saussurea salsa tended to form an “intensive” root architecture with high fractal dimension (FD) and low fractal abundance (FA) in plot I. “Diffusive” root architecture with low FD and high FA tended to form in plot III. The root of Saussurea salsa had less branch and more inclined to increasing the soil volume of root expansion in the far water area.