Assessment of the Effect of Applying Sustainable Irrigation Systems on the Growth of Three Selected Rangelands’ Plants in Semi-Arid Areas of Saudi Arabia

Rangelands of arid and semi-arid regions are facing severe issues due to climate change, desertification, and overgrazing, which are subsequently leading towards the degradation of native shrubs. Several approaches have been practiced so far in the restoration of rangeland; however, optimization of irrigation practice is considered to be a promising strategy to restore native shrubs’ growth, by improving water distribution and plants’ physiological growth. In this study, a field experiment was conducted across three semi-arid sites, including Al-Tamiryyat (Al-Jouf), Al-Sahwa (Al-Madina), and Al-Fuhaihil (Thadiq), to assess the impact of drip and sprinkler irrigation on the growth dynamics of region-specific native shrubs. Plant growth parameters like plant height, stem diameter, and crown size ratio were measured monthly over 12 months (June 2024–June 2025). Analysis of Variance (ANOVA) revealed that drip irrigation significantly enhanced growth performance compared to sprinkler and control treatments across all sites. Plant height increased up to 142% in Haloxylon persicum, while the stem diameter of Vachellia gerrardii expanded by nearly 198% under drip irrigation. Crown size ratio exhibited site- and species-dependent temporal patterns, with drip irrigation consistently supporting greater canopy expansion. Meanwhile, the interactions between irrigation type, species, and time were significant at most sites, indicating temporal and contextual variability in growth dynamics. Overall, these findings demonstrate that drip irrigation has substantial potential for the rangeland restoration in water-limited environments. However, future studies should assess the long-term impact of irrigation practices for a better understanding of soil–plant–water interactions to ensure the restoration of rangelands in arid regions.