Vegetative porous concrete (VPC) could effectively reduce the adverse impacts of engineering construction on the environment and adapt to the demands of sustainable development. In this article, shale ceramsite was selected as coarse aggregate and Cynodon dactylon was chosen as an experimental plant. Based on the conditions of two target porosities and four water–cement ratios, the mixture proportions of VPC were designed. Modified soil was made, in which fly ash, compound fertiliser, FeSO4 and vinyl acetate emulsion were mixed in yellow-brown loam. Planting substrate slurry made of modified soil, humus, vermiculite powder according to the proportion of 2:2:1 and the right amount of water. Given two planting structures, planting tests were conducted on the VPC. Results showed under the conditions of target porosity and grain composition, bulk densities of 12 groups of VPC varied between 600 and 800 kg/m³, compressive strengths of 28 days old were 5 MPa above and pH values varied from 11 to 12 in the porous concrete internal voids. Plant height exceeded 10 cm and plant covered more than 95% at the age of 60 days in both two planting structures. The results are great significance for using VPC to enhance slope landscape and prevent soil erosion, shallow landslides and other geological disasters.

Many measures have been applied to quarry slopes for ecological restoration; however, the performance of these measures has not been clearly evaluated. Thus, research evaluating the effects of the ecological restoration of quarry slopes in Caidian District was carried out to quantify the performance of different ecological restoration methods, to evaluate the effect of ecological restoration projects and to learn the applicability of different restoration technologies in Caidian District. The research can provide a reference for scientific decision-making in the follow-up management of ecological environments in Caidian District. First, the ecological restoration process of quarries in Caidian District was described in detail by visiting the relevant design and construction units. Through observational analysis from the aspects of applicable slope gradient, slope flatness requirements, project cost, the vegetation coverage conditions, the species diversity conditions and construction difficulty, the advantages and disadvantages, as well as the applicability of different ecological restoration technologies were preliminarily clarified. Then, the comprehensive evaluation index system of the ecological restoration effects was established by using the fuzzy AHP method. The ecological restoration effects of each sample plot were evaluated quantitatively based on the data of the evaluation indexes obtained by the field investigation and sampling analysis. Finally, according to the evaluation results, the existing problems in the follow-up management of the ecological restoration of quarry slopes in Caidian District were analyzed, and corresponding countermeasures and suggestions were proposed. The results showed that the quantitative evaluation results obtained by the comprehensive evaluation system of ecological restoration were consistent with the observational analysis results, and the validity of the evaluation system was proven.

Background: To quantitatively evaluate the contribution of plant roots to soil shear strength, the generalized equivalent confining pressure (GECP), which is the difference in confining pressure between the reinforced and un-reinforced soil specimens at the same shear strength, was proposed and considered in terms of the function of plant roots in soil reinforcement. Methods: In this paper, silt loam soil was selected as the test soil, and the roots of Indigofera amblyantha were chosen as the reinforcing material. Different drainage conditions (consolidation drained (CD), consolidation undrained (CU), and unconsolidated undrained (UU)) were used to analyse the influences of different root distribution patterns (horizontal root (HR), vertical root (VR), and complex root (CR)) and root contents (0.25%, 0.50%, and 0.75%) on the shear strength of soil-root composites. Results: The cohesion (c) values of the soil-root composites varied under different drainage conditions and root contents, while the internal friction angle (φ ) values remain basically stable under different drainage conditions. Under the same root content and drainage conditions, the shear strength indexes ranked in order of lower to higher were HR, VR and CR. The GECP of the soil-root composites with a 0.75% root content was 1.5–2.0 times that with a 0.50% root content and more than 5 times that with a 0.25% root content under the CD and CU conditions. The GECP in reinforced soil followed the sequence of CD > CU > UU. The GECP of the plant roots increased as confining pressure increased under CD and CU conditions while showed a complex change to the confining pressure under the UU condition. Conclusion: It was concluded that the evaluation of plant root reinforcing soil based on GECP can be used to measure effectively the influences of roots on soil under different drainage conditions and root distribution patterns.

After ecological restoration of high and steep slopes in the project disturbed area, soil properties, soil microorganisms, litter types and root types change with the succession of vegetation cover communities. However, the effects of different vegetation successional stages on soil respiration dynamics remain unclear. To elucidate trends and drivers of soil respiration in the context of vegetation succession, we used spatio-temporal alternative applied research. Vegetated concrete-restored slopes (VC) with predominantly herbaceous (GS), shrub (SS), and arborvitae (AS) vegetation were selected, and naturally restored slopes (NS) were used as control. SRS1000 T soil carbon flux measurement system was used to monitor soil respiration rate. The results showed that soil respiration (R_S) and fractions of all four treatments showed a single-peak curve, with peaks concentrated in July and August. During the succession of vegetation from herbaceous to arborvitae on VC slopes, R_S showed a decreasing trend, and GS was significantly higher than AS by 45%; Compared to NS, R_S was 29.81% and 21.56% higher in GS and SS successional stages, respectively, and 27.51% lower in AS stage. R_S was significantly and positively correlated with nitrate nitrogen (NO₃^–-N) and microbial biomass nitrogen (MBN), both of which are important factors in regulating R_S under vegetation succession. A bivariate model of soil temperature and water content explains the variability of Rs better. Overall, RS was higher than NS in the transition stage and lower than NS in the equilibrium stage of the vegetation community on VC slopes, and the R_S decreases gradually with the vegetation succession of artificial ecological restoration slopes.