Synergistic optimization of mechanical strength and vegetative growth in ecological slope restoration materials through mix ratio design

Ecological slope restoration is crucial for environmental balance, disaster mitigation, and sustainable development. This study evaluates a novel vegetation-growing material with high strength, plant growth performance, and cost efficiency. The key innovation lies in the introduction of a composite ecological regulator (CER), which synergistically balances mechanical strength and ecological functionality by addressing the limitations of conventional materials (e.g., high cement content, pH imbalance). Using orthogonal and secondary optimization tests, we systematically resolved the conflicting effects of cement, CER, microsilica powder, rice husk, and farmyard manure on vegetative characteristics (germination rate, plant height) and physicochemical properties (compressive strength, pH, porosity). Results demonstrate that cement enhances bond strength but increases pH and reduces porosity, with an optimal dosage of 4%. CER improves nutrients and microbial activity but inhibits growth when excessive, with an optimal dosage of 7.5% of cement. Microsilica powder lowers pH and enhances strength, but exceeding 50% of cement reduces porosity. Rice husk improves pore distribution, while 6% organic matter optimizes water retention, germination rate, and plant height, increasing them by 130% and 163%, respectively. The optimal mix ratio was determined as soil:cement:CER:microsilica powder:rice husk:farmyard manure = 100:4:0.3:2:6:2. Research results provide new ideas for material-vegetation synergistic slope protection and ecological restoration.