## 3 Results  
### Results on pH and EC Determinations  
The pH of soil is called a \"master variable\" due to its role in many chemical and biochemical processes. It indicates the degree of acidity or alkalinity. Between pH and biological, chemical, and physical properties of soil, there is a bidirectional relationship, which controls biological processes, and it is controlled by the leaching of cations such as Ca, Mg, K, and Na. The pH of soil depends on the ratio between H\({}^{+}\) and OH\({}^{-}\). H\({}^{+}\) ions in soil can be a result of the dissolution of CO\({}_{2}\) in soil's moisture, humic residues, nitrification of NH\({}_{4}\), and N uptake by plants. It can be said that soil pH has implications on nutrient availability for crops and other biochemical processes, whereas some biogeochemical processes can influence the pH evolution. Thus, crop productivity may be related to the pH value of the soil. Generally, the optimum pH interval for agricultural crops is between 5.5 and 7.5 [43].  
In this work, the pH and EC of the cultivation substrates were determined before and after plant cultivation. It was found that in the growth and development of _Salicornia europaea_ L., there were no significant differences among the cultivation variants. Also, there were no significant differences between the pH values before and after cultivation of _Salicornia europaea_ L. (Figure 1).  
After cultivation in the greenhouse experiment, the analysis of the samples showed that S1 had a pH of 7.65 \(\pm\) 0.003 (mean \(\pm\) standard error (SE)), S2 had one of 8.52 \(\pm\) 0.06, S3 had one of 7.31 \(\pm\) 0.005, and R had one of 5.29 \(\pm\) 0.10. According to the United States Department of Agricultural National Resources Conservation Service, all soils were defined as slightly alkaline (>7.4), neutral (\(\geq\)7.3), and very alkaline (>8.5), except for the reference soil (R), which was very acidic.  
In general, agricultural crops are found on soils in the range of slightly acid-slightly alkaline. Within this interval, it is found that the bioavailability of nutrients is optimal and also influenced by several factors including the pH value [44].  
The obtained EC values are presented in Figure 2. It can be observed that the cultivation of _Salicornia europeaea_ L. may influence the EC of the soil; for each tested substrate, the differences between the before and after cultivation values are significantly different. This may be due to the ability of the plant's mechanism to tolerate salt and heavy metal toxicity, having, among other characteristics, a phytoextraction role. In the same way, _Salicornia bigelovii_[45], _Salicornia brachiata_, and _Salicornia iranica_ have the same characteristics.  
The presented results can be easily correlated with the variation of the Na content of the plant obtained on the cultivation substrates, as described below. Therefore, the mechanisms by which plants extract salt from saline soils and the consequences of this process on the soil-plant system are diverse. For instance, it was described that the main mechanisms for the role of plants in remedying salted soils are (1) the reduction of pH, which increases the solubility of CaCO\({}_{3}\) and, therefore, makes Ca\({}^{2+}\) available for the exchange of cations with Na\({}^{+}\), and (2) the absorption by plants of dissolved salts and/or Na in particular [46].  
Figure 1: The impact of _Salicornia europeaea_ L. cultivation on the pH variation. Values followed by the same letter(s) do not differ significantly at \(p\) = 0.05.