Effects of gypsum, peat moss, and date-palm biochar on arid soil quality and seedling performance of Acacia tortilis in Fujairah

Lower soil quality is one of the biggest challenges that limit farming systems under arid regions. However, little is known about the use of organic components and their synergistic effects to restore arid soil quality. Here, we evaluated the impacts of peat moss, biochar, and gypsum on the seed germination, seedlings growth and nodulation of Acacia tortilis considering their separated and combined effects under natural conditions. Acacia tortilis seed germination, seedlings growth and nodulation were exposed to the following treatments: (a) gypsum alone, (b) gypsum + peat moss, (c) gypsum + biochar, (d) gypsum + peat moss + biochar with three levels of gypsum applications including 0, 5 and 10%, and one rate of date palm biochar (2%). Based on the findings, photosynthetic photon flux density (PPFD) values (1255.69 µmol m − 2 s − 1 ) and temperatures (40.04 °C) were greater in the noontime, while relative humidity values (29.68%) were lower. Soil treated with peat moss alone had a higher pH (7.43), while electrical conductivity (EC; 2.36 mS cm − 1 ), and water holding capacity (WHC; 64.33%) were greater in soils treated with all three agricultural components. The amounts of potassium, magnesium, manganese, iron, lead, chromium, cobalt, and copper were less in the soil treated with the three agricultural materials. Germination percentage (95.55%), seed vigor index (9.67), shoot length (12.33 cm), leaves number/plant (10.66), shoot dry weight (0.1 g), root dry weight (0.03 g), chlorophyll a (0.76 mg g − 1 ), chlorophyll b (0.24 mg g − 1 ), total carotenoids (0.16 mg g − 1 ), ash (5.71%), nodules number/plant (7), and nodule length (6.66 mm) were higher in the soil treated with the three mixtures whereas, root length was highest (16.66 cm) in the mixture of gypsum and biochar. The results of this study suggest that emphasizing these agricultural materials while farming could potentially and positively optimize arid soil quality and then help in water and nutrients retention.