The influence of Caragana korshinskii shrub on soil and hydrological properties in a revegetation-stabilized desert ecosystem |
| |
| Authors: | Yan-Xia Pan Xin-Ping Wang Xin-Rong Li Ya-Feng Zhang Rui Hu Hao Zhang |
| |
| Institution: | 1. Shapotou Desert Research and Experiment Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, Chinapanyanxia@gmail.com;3. Shapotou Desert Research and Experiment Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, China |
| |
| Abstract: | AbstractShrub-induced spatial heterogeneity of soil and hydrological properties are common in arid and semi-arid ecosystems. To examine the influence of shrubs on spatial patterns of soil physical, chemical and hydrological properties, the typical sand-fixation species, Caragana korshinskii, was studied in the Shapotou area of the Tengger Desert, China. Miniature cylinder infiltrometers were used to quantify the spatial variations of infiltration rate in the soils, and were installed at 20-cm intervals around the shrubs. Meanwhile, soil samples were collected at 0–5 cm depth every 10 cm to analyse their physical and chemical properties and soil moisture content. The results indicate that the various measured parameters showed a gradational change from sub-canopy to open space. The establishment of shrubs formed obvious “fertile islands” where more soil nutrients collected. The total nitrogen (TN), soil organic matter (SOM), electrical conductivity (EC) and surface soil moisture content decreased gradually from around shrub stems to the interspace. The sand content around shrub stems was significantly higher (p < 0.05), and decreased gradually from the centre towards the outside microsites. The silt and clay contents showed opposite variability characteristics. The variation of soil bulk density was less within 140 cm distance from the stem, and no abrupt change was found at the shrub’s drip line. No significant tendency was found for the soil pH values. The steady infiltration rates declined with increasing stem distance and then tended to be stable, and no abrupt change occurred at the position of the overhead canopy margin. The increase of infiltration rate was rapid nearer to the stem; the variability trend can be fitted by a log-log (power function) model. This study indicated the gradational change in soil and hydrological properties, which was not consistent with the binary division of shrubs into “canopy” and “interspace” zones. Editor Z.W. Kundzewicz |
| |
| Keywords: | shrubs physical properties chemical properties hydrological properties infiltration rate |
|
|
