Soil moisture characteristics curve under different plant treatments.

(a is for Medicago; b is for Cynodon dactylon; c is for Lolium perenne; d is for Control treatment).</p

Transient swelling rate of soil under different plant treatments.

Transient swelling rate of soil under different plant treatments.</p

Axial line shrinkage of soil under different plant treatments.

Axial line shrinkage of soil under different plant treatments.</p

Microscopic morphology of soil under different treatments at 200 μm scale.

(a is for Control treatment; b is for Cynodon dactylon; c is for Medicago; d is for Lolium perenne).</p

Root characteristics of different types of herbaceous plants.

Root characteristics of different types of herbaceous plants.</p

The number of root tips, root forks and root crosses of different plants.

The number of root tips, root forks and root crosses of different plants.</p

Research area location map.

(Yaoshi Town, Shangluo City, Shaanxi Province, China).</p

Distribution of root length at different diameter classes for three herbaceous.

Distribution of root length at different diameter classes for three herbaceous.</p

Correlation analysis between root diameter class and soil linear shrinkage and swelling rate under Cynodon dactylon treatment.

P: swelling rate of soil; X1, X2, X3: the line shrinkage of the minimum, maximum and inflection points of suction; G1, G2, G3, G4, G5, G6: respectively denote the root lengths of 0</p

Content of organic matter in soil under different treatments.

Content of organic matter in soil under different treatments.</p