الفهرس 
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Abstract
The main problem facing Egypt recently is the shortage of available water resources. Therefore, farmers resort to using wastewater for irrigation. So, the current study aimed to assess the effects of wastewater irrigation on soil properties, agricultural crops (Archis hypogea and Pisum sativum) and edible weeds (Sonchus oleraceous L., Beta vulgaris L. and Cichorium endivia L.) productivity. In addition to study the effect of wastewater on the nutritional value of plants and human health.
Shibin Al Kanater sector is chosen for this study. There are two irrigation sources in the study area, El-sharkawia canal and Belbais drain. The physicochemical characteristics of drainage water, canal water, drainage water-irrigated soils and canal-irrigated soils were estimated. The vegetative and yield traits of crops and edible weeds were determined including their photosynthetic pigments, organic and inorganic nutrients content, and heavy metals content. The main results are summarized as following:
1. According to WQI, results indicated that the water quality of El-sharkawia canal is good for irrigation usage, while Belbais drain classified as unsuitable for irrigation.
2. Soil irrigated with drainage water recorded pH value 6.95, and 7.01in soil irrigated with canal water. In addition, the EC of soil irrigated with drainage water (297.33 μs cm-1) was higher than that of soil irrigated with canal water (283.0 μs cm-1). All anions (Co3-2, HCO3-, Cl- and SO4-2) and cations (Ca++, Mg++ and K+) recorded a higher concentration in soils irrigated with drainage water
3. Soil Irrigated with drainage water resulted in accumulated high significant concentrations of Fe, Zn, Cu and Cd (157.7, 30.2, 6.1 and 3.8 mg kg-1, respectively), also, the soil irrigated with canal water had concentrations of Cu and Cd (3.5 and 2.8 mg kg-1, respectively) exceeded than their permissible concentrations.
4. Drainage water irrigation had negative effect on productivity of peanut and pea plants. It decreased shoot, pods and seed productivity of peanut with reduction % 42.9, 50.0 and 52.5%, respectively and reduced shoot productivity, pods yield and seed productivity of pea with reduction % 20.1, 37.3 and 48.9%, respectively.
5. Biomass productivity of Sonchus oleraceous, Beta vulgaris and Cichorium endivia increased as a result of drainage water irrigation with increasing percentage 27.9, 19.6 and19.1%, respectively.
6. Irrigation with drainage water decreased chlorophyll a and b in peanut and pea plants. While, carotenoids were increased in peanut leaves but decreased in pea leaves. On the other side, irrigation with drainage water significantly increased the photosynthetic pigments of edible weeds.
7. In peanut seeds, irrigation with drainage water decreased the content of N, P and K, but increased the content of Ca and Mg, compared to irrigation with canal water. In pea seeds, drainage water significantly decreased Ca and Mg content. Nitrogen, phosphorus and potassium contents had significant increase in pea seeds irrigated with drainage water than that irrigated with canal water.
8. In shoots of C. endivia plants that were irrigated with drainage water; Ca, Mg, N and K content increased but P content decreased. The contents of Ca, Mg and P were decreased in shoots of S. oleraceus plants irrigated with drainage water but the content of N and K increased. In B. vulgaris shoots, high contents of Ca and Mg were recorded in plants irrigated with canal water. On the other hand, NPK content increased in shoots of plants irrigated with drainage water.
9. Drainage water irrigation resulted in decreasing carbohydrate content, crude protein and crude fats content, and an increase in total soluble sugar content in peanut plants. However, in pea plants irrigated with drainage water; carbohydrate content and total soluble sugar decreased but crude protein increased. On the other side, irrigation with drainage water increased carbohydrate content, crude protein and total soluble sugar in the edible weeds.
10. Irrigation with drainage water had negative effect on nutritive value of studied crops. Irrigation with drainage water compared to canal water decreased the DCP by 62.4% in peanut seeds but increased in pea seeds from 27.8 to 31.0%. While the TDN increased in peanut seeds from 71.9 to 81.7% and decreased in pea seeds from 41.5 to 39.2%. In addition, irrigation with drainage water decreased gross energy of peanut and pea seeds. On the other hand, the studied weeds irrigated with drainage water showed increasing in the digestible crude protein and gross energy.
11. Arachis hypogea and P. sativum plants had high tendency to accumulate high contents of Fe, Cu, Mn, Zn and Cd in their roots under irrigation with canal and drainage water. Also, peanut plants irrigated with drainage water were found to store Zn, Mn, Cu, Pb, and Cd in their seeds, and pea seeds could store Zn, Mn, Cu and Cd.
12. Beta vulgaris, S. oleraceus and C. endivia plants irrigated with drainage water could accumulate Fe, Zn, Mn and Cu in their roots. In addition, B. vulgaris plants irrigated with drainage water could translocate Mn from roots to shoots with TF more than the unit. Cichorium endivia plants irrigated with canal and drainage water recorded TF more than the unit for Zn, Mn, Co, Pb and Cd. on the other hand, S. oleraceus plants irrigated with canal and drainage water recorded TF more than the unit for Cu, Pb and Cd.
13. Peanut seeds irrigated with drainage water recorded HRI more than the unit for Mn, Pb and Cd, but in pea seeds irrigated with drainage water, Mn and Cd had HRI more than the unit for adults and children.
14. Cichorium endivia, S. oleraceus and B. vulgaris plants irrigated with canal water indicated HRI less than the unit for adults and children for all heavy metals. On the other side, Cu, Pb and Cd showed HRI more than the unit in C. endivia plants irrigated with drainage water for adult and children. Cadmium and copper for adults and Mn, Cu and Cd for children were recorded HRI more than the unit for S. oleraceus plants irrigated with drainage water. In B. vulgaris plants, Cu and Cd showed high health risk index for adult and Mn, Cu, Pb and Cd for children in plants irrigated with drainage water.
15. Peanut and pea plants irrigated with Belbais drain in the study area had risk on the human’s health consuming these seeds.
16. High concentration of heavy metals in the studied edible weeds has serious impact on humans and animals when consumed them. On the other hand, they may be has important role in phytoremediation by phytoextraction and bioaccumulation of heavy metals.
17. Irrigation with drainage water is not suitable for irrigation of crops and it had negatively effects on the general economy in terms of wasting time, effort and money, as well as human health.