# Evaluation of Agricultural Soil-Improving Zeolite for Improving Irrigation Water Quality
## 3 Results and Discussion
### Irrigation Water Characterization  
The comprehension of water quality empowers farmers and project managers to make judicious decisions concerning the volume and frequency of irrigation. Furthermore, it enables the implementation of apt management practices aimed at mitigating adverse impacts. The average pH of the irrigation water before treatment was approximately 8.35. The chemical characterization of the initial samples is shown in Table 4, where the obtained values are compared with the maximum limits for irrigation water defined by the FAO [11], as well as the restrictions on water use for irrigation [11; 49]. Among all identified elements, only sodium and boron presented higher usage restrictions due to their high concentrations. Thus, in this case, only boron and sodium were evaluated, as the other elements were within permissible limits for agricultural water use. It is crucial to emphasize that, in the present study, water characteristics and the criteria for suitability and adequacy for use as irrigation water are based on the FAO document \"Water Quality for Agriculture\" That report not only presents water-quality guidelines for irrigation, supported by specialized scientific-technical reports, but also establishes, defines, and indicates potential restrictions for its use. The approach in the document underscores a problem-solving perspective and highlights the importance of comprehending the long-term effects of low-quality water in agriculture. The text also \begin{table}
\begin{tabular}{l c c c c c c c c c c} \hline \hline  & & & & & & & & & & \\ \hline SiO\({}_{2}\) & Al\({}_{2}\)O\({}_{3}\) & CaO & Na\({}_{2}\)O & Fe\({}_{2}\)O\({}_{3}\) & FeO & K\({}_{2}\)O & TiO\({}_{2}\) & MgO & P\({}_{2}\)O\({}_{5}\) & pH \\ \hline
63.00 & 11.57 & 5.78 & 2.39 & 1.82 & 0.81 & 1.49 & 0.45 & 0.92 & 0.09 & \\ (3.00) & (1.20) & (0.62) & (0.26) & (0.81) & (0.02) & (0.40) & (0.01) & (0.53) & (0.01) & \\ \hline \multicolumn{8}{c}{**Physical Characteristics**} \\ \hline Surface area & & & & m\({}^{2}\)/g & & 40 & & & & \\ \hline Bulk density & & & g/L & & 0.98 & & & & \\ \hline Cation-exchange capacity & & & mg/g & & 1.8 & & & & \\ \hline Particle size & & & mm & & 1.0–2.5 & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Average chemical composition (%) and physical characteristics of the natural zeolite used. Mean values with standard deviation in parentheses. provides laboratory tools for assessing water quality and underscores that the guidelines are management tools, requiring adaptability based on local conditions. In most cultivated plant species [13], toxicity symptoms typically manifest as chloride As mentioned earlier, boron is an essential micronutrient for plant development [14,50]. However, the threshold between the concentration required for proper plant development (0.3-0.5 ppm) is very close to the levels that exhibit toxicity, ranging from 0.6 ppm to 1.0 ppm manifestations in leaves, phenotypically similar to leaf burns, with an initial appearance at the margins and subsequent expansion toward the basal portion [13,51]. On the other hand, sodium, which is the main element in water and/or soil salinity, has significant negative impacts on plant development, primarily due to the increase in soil osmotic pressure, which directly interferes with plant nutrition by reducing the plant's ability to adsorb water, altering the homeostasis of root cell ions [52,53]. [PERSON] et al. [54] categorized the damage caused by excessive salt presence as identical to that caused by water stress-induced \"wilting\". Moreover, various studies indicated a direct relationship between salinity and photosynthesis, as it limits CO2 diffusion and reduces photosynthetic pigment content [55,56]. More specifically, in the case of citrus, as early as 1993, [PERSON] [57] highlighted how soil salinity significantly limits citrus production. The author indicated a reduction of about 13% in production for every 1.0 dS/m increase in the electrical conductivity of the saturated soil extract from 1.4 dS/m.