Design Optimization of Biocrust-Plant Spatial Configuration for Dry Ecosystem Restoration Using Water Redistribution and Erosion Models

Abstract

Land degradation is one of the main threats to dryland sustainability in the next decades, hence restoration of the degraded land from drylands is an urgent need to maintain ecosystem functionality and their ability to provide ecosystem services. To achieve this goal, restoration practices should pursue the recovery of the main ground components, arranged in an optimal spatial configuration, to mimic undisturbed natural conditions. Drylands function as complex ecohydrologically coupled systems in which interplant source areas, frequently covered by biocrusts, act as sources of runoff and nutrients to adjacent vegetation, which act as sinks for these resources. Thus, one way to increase dryland restoration success is through an optimal spatial configuration of biocrusts and plants that maximizes an efficient use of the limited resources within the system. In this study, we selected a degraded slope from a limestone quarry located in Almería province (SE Spain) and modeled how active restoration of the biocrust through soil inoculation with cyanobacteria and its combination with different spatial configurations of vegetation affected runoff redistribution and erosion. For that, we applied the spatially distributed Limburg Soil Erosion Model (LISEM) which was able to predict the erosion measured on the slope during the study period with low error (RMSE = 17.8%). Modeling results showed that the introduction of vegetation on the degraded slope reduced runoff between 2 and 24% and erosion between 4 and 17% for the scenario with plants compared to the one without restoration management. Of all the vegetation spatial configurations tested, the one that provided better results was the scenario in which plants were located in the areas of higher water accumulation (higher topographic wetness index). Moreover, we found that active biocrust restoration by cyanobacteria inoculation significantly reduced erosion by 70–90%, especially during the first stages of plant development, while maintaining water supply to vegetation. These findings highlight the potential of water redistribution and erosion simulation models to identify the most optimal spatial configuration of ground covers that maximizes water and nutrient supply to vegetation, while minimizes water, sediment, and nutrient losses by erosion, thus serving as an efficient tool to plan restoration actions in drylands.

Biological soil crusts decrease infiltration but increase erosion resistance in a human-disturbed tropical dry forest

“…Currently large parts of dry forests are threatened by desertification caused by unsustainable anthropogenic land exploitation ( Miles et al, 2006 ; Vieira et al, 2015 ). However, biocrusts have been proven to be useful tools for nature-based dryland restoration and to combat land degradation and desertification ( Dadzie et al, 2022 ; Maggioli et al, 2022 ). Their influence could become even more important, since dry forests will face dramatic changes and climate extremes, particularly an increase in drought stress for vascular plants ( Torres et al, 2017 ).…”

Most suitable plant communities for the slope reclamation of the Zhengzhou-Xinxiang section of the Beijing-Hong Kong-Macao expressway

“…Cao et al [ 10 ] designed a runoff field on a highway slope with the optimum plant community combination identified through experimental data. Scholars have also suggested that plant communities should be configured to include trees, shrubs, and grasses that are drought- and cold-resistant and thus show high environmental adaptability [ 11 ]. Research has also revealed that combining legumes with perennial herbs benefits slope reclamation [ 12 ].…”

Compost promotes biocrust and plant growth in greenhouse cocultures for dryland restoration

“…So far, restoration strategies using plants and biocrusts have mostly developed as independent basic and applied research areas. However, integration of these restoration disciplines, by practices including plant and biocrust co‐introduction, maybe a more efficient means for initializing ecosystem structural and functional restoration (Maggioli et al 2022). In addition, the value of plant/biocrust interactions has recently been identified as an essential topic worthy of further study to improve ecosystem restoration, given the positive effects of one on the other (Antoninka et al 2021; Bowker et al 2022).…”