Wastewater Reuse for Alfalfa Production in the Gaza Strip

Geography, population growth, and politics combine to make the Gaza Strip a worst-case scenario for water resource planners. Potable water sources are shrinking while at the same time, the proportion of potable water used for irrigation is increasing. To assess whether water from wastewater treatment plants could be safely used for irrigation, this study collected 51 treated wastewater, 51 sludge, 44 soil, 30 alfalfa, and 24 oranges and lemon samples and analyzed the samples for major and trace elements. Both Inductively Coupled Plasma - Optical Emission Spectroscopy (ICP/OES) and X-ray fluorescence (XRF) were used for the determination of Ag, Al, As, B, Ba, Br, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, Se, Sr, Zn, Zr, Th, and U in digested and solid samples, respectively. Treated wastewater characteristics showed a very good agreement with the guidelines of many developed countries. Moreover, none of the tested parameters in soil showed concentrations exceeding their corresponding background values. For alfalfa, both ICP/OES and XRF showed Zn concentrations in leaves (36–42 mg/kg, respectively) higher than in root (19–31 mg/kg, respectively). The Cu showed also the same trend as Zn. No significant variation was observed between the concentrations of Cr and Mn in plant parts; concentrations of Co and Pb were two times higher in roots than in leaves and stems. The findings confirm that treated wastewater is safe to use for irrigation in Gaza. Collecting and reclaiming this water can contribute to wise use of each drop of water available.     

Effects of salinity level on the survival,growth, feed utilization,carcass composition,haematological and serum biochemical changes of juvenile Meagre (Argyrosomus regius) (Asso, 1801) grown in ground saltwater

A study was performed to examine the effects of salinity on water quality, fish performance, carcass composition and haemato‐biochemical parameters in juvenile meagre, Argyrosomus regius. Fish (5.0 g) were stocked in fibreglass tanks at four salinity levels: 8‰, 16‰, 24‰ and 32‰, and fed a pelleted diet (47/17 protein/lipid) for 56 days. Results indicated that the growth, feed utilization, carcass composition and haemato‐biochemical parameters of meagre gradually improved with the increase in salinity up to 24‰ and then significantly (p ≤ .05) decreased at 32‰. The survival per cent showed a significant decrease when A. regius exposed to 8‰ salinity. An improvement with 32%, 47% and 34.1% of FCR, protein productive value and energy utilization was detected at 24‰ compared with 8‰ salinity respectively. The highest content of protein and the lowest of lipids were recorded in fish carcass at 24‰ compared with the opposite trend at 8‰ salinity. The 24‰ salinity treatment exhibited the highest value of haemoglobin (4.9 g/dl) and the lowest ratio (0.73) of albumin/globulin. The serum total protein, albumin and globulin were significantly higher at 24‰ and 32‰ salinity than those at 8‰ and 16‰ salinity groups. These findings indicate that 24‰ salinity level might be the best for meagre.     

Occurrence of Pesticides in Groundwater and Topsoil of the Gaza Strip

Agricultural activities in the Gaza Strip have been associated with excessive and uncontrolled use of dozens of pesticides. Accordingly, groundwater and soil are potentially contaminated causing severe threat to the crowded population. The present study describes a 3-year program to monitor types and levels of contamination by 52 pesticides in 94 groundwater wells in Gaza. Two analytical techniques (GC/MS and HPLC/MS) were applied to achieve this objective. Water from 63 wells showed no detectable levels of pesticides or levels that were much lower than the allowable limit (0.5 μg/L) of the German and the European Commission (EC) standards for groundwater. Municipal groundwater wells located in residential areas showed better quality than private wells in agricultural regions. Atrazine, atrazine-desisopropyl, propazine, simazine were detected in 18, 15, 8 and 5 wells with average concentrations of 3.5, 1.2, 1.5 and 2.3 μg/L, respectively. A linear correlation was found between the chloride concentrations in groundwater and atrazine for the same private wells. Generally speaking, shallow aquifers in sandy substances in areas of low annual precipitation in the southern areas of Gaza showed detectable concentrations of pesticides. Pesticides were more abundant in clay soils of the northern area. A linear regression analysis showed a correlation coefficient of r = 0.87 between the strawberry greenhouses and the occurrence of propazine, sebutylazine, terbutylazine, 4,4′-DDT, 4,4′-DDE, and 4,4′-DDD in soil. The averages of propazine, sebutylazine and terbutylazine were 19, 13 and 39 μg/kg, respectively. Two soil samples from greenhouses showed maximum contents of 4,4′-DDE and 4,4′-DDT up to 1150 and 823 μg/kg, respectively. Groundwater needs to be assessed for pesticide contamination on a routine basis to protect the health of Gaza's residents. Where levels of pesticides are found to exceed levels that protect health, alternative water resources need to be found for drinking and possibly other household uses.