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The soil seed bank (SSB) is a valuable reservoir of seeds hidden in the soil, playing a crucial role in vegetation establishment under adverse environmental conditions. However, limited knowledge exists regarding the effects of restoration measures on SSB, particularly in arid ecosystems. This study examines the impacts of oil mulching (1 and 3 years after application) and plantations (15-year-old) on the diversity and composition of SSB and aboveground vegetation (AGV) compared to non-restored areas. The results indicate that species richness was low in the studied area (36 species from 16 families), with SSB contributing less than AGV (11 and 34 species, respectively). The highest number of exclusive species was observed in the plantation treatment, while the lowest was recorded in the 1-year mulching treatment. The diversity indices revealed that the highest values occurred in the plantation and 3-year mulching plots. Seed density was significantly greater in the plantation area compared to the other treatments. The analysis of plant composition demonstrated that the plantation treatment was distinct from other treatments, with the 3-year mulching site being the closest to it. These findings suggest a trade-off between the short-term and long-term effects of oil mulching, where initial negative impacts diminish over time, leading to positive ecological outcomes. Ultimately, oil mulching, in combination with afforestation, fosters a favorable microclimate, improving AGV and SSB diversity and composition.

The impact of oil mulch on seed germination and the establishment of seedlings and cuttings has always been a question associated with its use. The aim of this study was to evaluate the efficiency of the polymer Poly-Lattice in seed germination and plant establishment and compare it with oil mulch. For this purpose, the study was conducted in two phases: greenhouse and field experiments.

In the greenhouse experiments, the effect of this polymer compared to oil mulch on the germination and establishment of Haloxylon seeds was examined using a completely randomized design with four treatments (oil mulch, Poly-Lattice solution with water, Poly-Lattice mixed with sand, and control) in three replications. Three weeks after planting, the lowest germination rate was observed in the Poly-Lattice-sand mixture treatment (a slurry with a thickness of 2 to 3 mm), while the highest germination rate belonged to the oil mulch treatment.

Meanwhile, in the field experiment, Poly-Lattice did not show a significant difference from oil mulch in the establishment of planted seedlings and cuttings. However, the average measured traits indicate that the percentage of seedling and cutting establishment was significantly higher in the oil mulch treatment compared to other treatments. This can be attributed to the better stabilization of the area by oil mulch.

This article investigates the impact of oil mulching with petroleum products on water quality. Oil mulch, composed of heavy petroleum byproducts, has the potential to contaminate water resources with heavy metals and hydrocarbons. The study examined oil mulch samples from various regions in Khuzestan Province over short-term, medium-term, and long-term periods, as well as samples from the Abadan refinery under laboratory conditions simulating natural environments with a 24-hour contact time with water. The results revealed that oil mulch does not significantly increase water pollution in terms of heavy metals, and the levels of hydrocarbons detected were below permissible limits. The study concludes that while oil mulch may contribute to minor increases in certain pollutants, it does not pose a significant threat to water quality in terms of heavy metals and hydrocarbons.