Abstract
Biological soil crusts (BSCs, or biocrusts) have important positive ecological functions such as erosion control and soil fertility improvement, and they may also have negative effects on soil moisture in some cases. Simultaneous discussions of the two-sided impacts of BSCs are key to the rational use of this resource. This study focused on the contribution of BSCs while combining with specific types of vegetation to erosion reduction and their effects on soil moisture, and it addressed the feasibility of removal or raking disturbance. Twelve plots measuring 4 m × 2 m and six treatments (two plots for each) were established on a 15° slope in a small watershed in the Loess Plateau using BSCs, bare land (as a control, BL), Stipa bungeana Trin. (STBU), Caragana korshinskii Kom. (CAKO), STBU planted with BSCs (STBU+BSCs) and CAKO planted with BSCs (CAKO+BSCs). The runoff, soil loss and soil moisture to a depth of 3 m were measured throughout the rainy season (from June to September) of 2010. The results showed that BSCs significantly reduced runoff by 37.3% and soil loss by 81.0% and increased infiltration by 12.4% in comparison with BL. However, when combined with STBU or CAKO, BSCs only made negligible contributions to erosion control (a runoff reduction of 7.4% and 5.7% and a soil loss reduction of 0.7% and 0.3%). Generally, the soil moisture of the vegetation plots was lower in the upper layer than that of the BL plots, although when accompanied with a higher amount of infiltration, this soil moisture consumption phenomenon was much clearer when combining vegetation with BSCs. Because of the trivial contributions from BSCs to erosion control and the remaining exacerbated consumption of soil water, moderate disturbance by BSCs should be considered in plots with adequate vegetation cover to improve soil moisture levels without a significant erosion increase, which was implied to be necessary and feasible.
Highlights
Biological soil crusts (BSCs, or biocrusts) are complex communities containing bacteria, fungi, lichens, and moss cemented with soil particles
Time domain reflectometry (TDR, IMKO Company, Germany) with intelligent microelements was used to monitor the variation in the soil moisture at depths of 0 to 300 cm in the middle of each plot (Fig 2) in June and September of 2010, and one probe pipe was installed before BSC transplant or vegetation planting in the middle of each plot
The runoff decreased in the following order: Caragana korshinskii Kom. (CAKO)+BSCs > CAKO > Stipa bungeana Trin. (STBU)+BSCs > STBU > BSCs > BL
Summary
Biological soil crusts (BSCs, or biocrusts) are complex communities containing bacteria, fungi, lichens, and moss cemented with soil particles. These layers represent the typical ground cover in arid and semi-arid regions and have important ecological functions [1,2,3]. Under different conditions, researchers have reported positive, negative, and neutral relations between BSCs and rainfall infiltration, water evaporation, and vegetation succession [10]. Comprehensive investigations on the effects of BSCs on hydrology, soil erosion, and rainfall redistribution are highly valuable for both theoretical and practical purposes, with the aim of understanding a specific condition or region. Understanding the positive significance and negative effects of BSCs is the key to balancing between protection and disturbance and to realizing the efficient utilization of these resources
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
