Effect Of Using Reclaimed Water Via Furrow And Subsurface Drip Systems Under Alternate Partial Root-Zone Irrigation Mechanism On Crops Growth And Soil Properties

Water,as the most important resource for life,has been a central issue on the international agenda for several decades.Yet,the world’s clean freshwater supply is steadily decreasing due to climate change and extensive agricultural water demand for irrigated lands.The growing population in conjunction with water scarcity forces us to search for alternative sources of irrigation water as well as integrate it with irrigation strategies for agricultural expansion in order to meet the objectives of sustainable development.Therefore,water resources should be used with greater efficiency,and the use of non-traditional water resources,such as reclaimed wastewater（RW）,should be increased.Reusing RW could be an alternative option to increase water resources.Thus,many countries have decided to turn wastewater into an irriga-tion resource to help meet urban demand and address water shortages.However,because of the nature of that water,there are potential problems associated with its use in irrigation.This study was carried out in China over three years（2017,2018,and 2019）to illuminate the importance of using RW in irrigation as an alternative freshwater source.As well as to study the effects of two types of water quality（reclaimed wastewater（RW）and clean water（CW））,two types of irrigation methods（full irrigation（FI）and alternate partial root-zone irrigation（APRI））,and two types of irrigation techniques（furrow irrigation（FUI）and subsurface drip irrigation（SDI））on the fresh fruit yield（FY）,irrigation water use efficiency（IWUE）,nitrogen use efficiency（NUE）,and the main quality parameters of tomatoes.In addition,this work eval-uated the effects of these experimental factors on soil properties in regard to nitrate nitrogen（NO₃--N）content,Soil water content（SWC）,electrical conductivity（EC）,p H,and organic matter（OM）of Soil.The tomato fruit quality parameters studied were vitamin C（VC）,total acidity（TA）,protein content（PC）,and total soluble sugar content（TSS）.The APRI treatments obtained 70%of the FI irrigation water vol-ume.The experiment used a completely random block design and was undertaken over three growing spring seasons in China.The irrigation treatments in this study were:（1）SDI with APRI;（2）SDI with FI;（3）FUI with APRI;and（4）FUI with FI.These treatments were done under RW and CW.Thus,the experiment consisted of eight treatments.In this study the CROPWAT model was used to explore its ability to evaluate irrigation scheduling and performance during the tomato-growing stages.The main results obtained were as follows:-The highest value of FY was obtained under RW throughout the three years.The analysis of vari-ances in the three years of the experimental period showed a significant effect（p<0.05）of irrigation water quality,irrigation methods,and irrigation techniques on the yield throughout the three years.In addition,there was a significant effect（p>0.05）of the interaction between the experimental factors on the yield throughout the first and second years.The highest values of IWUE were obtained under APRI compared with FI throughout the three years,whether under RW or CW.In contrast,the highest values of yield and NUE were obtained under FI throughout the three years.The yield,IWUE,and NUE values under RW were higher than those under CW.-Regarding the tomato quality,the results reveal that many measurements under RW had the highest values compared with CW,except in PC.The vast majority of values measured for PC under CW were slightly greater than those under RW.Moreover,the results reveal that tomato quality in many measure-ments under APRI treatments increases compares with FUI.The statistical analysis generally shows that the fruit quality parameters were not significantly（p>0.05）affected by the interaction between the irri-gation treatments.-The average soil NO₃--N content in the depth of 0-50 cm was significantly influenced（P<0.05）by irrigation water quality and irrigation techniques throughout the first and third years.However,in the three years,there was no significant influence（P>0.05）for the irrigation methods and the interaction of the experimental factors on the content of NO₃--N in all depths.-Analysis of variances showed that there was no significant effect（P>0.05）for the experimental factors and the interaction between them on the soil EC,PH,and OM over the three years.Although there were no significant differences between the treatments,throughout the three years,the EC values under the RW treatments were higher than the EC values under the corresponding treatments that were irrigated with CW.-The SWC data revealed that SWC under SDI was higher than that under FUI.the SWC for FUI-APRI treatment under RW and CW was lower than that of the other treatments under the three years.In contrast,the SWC under SDI-FI was the highest among all the treatments throughout the three years.-Irrigation schedules Evaluation using the model of CROPWAT showed that different irrigation water levels need to integrate irrigation application methods.Under various management conditions and water supply methods,the CROPWAT model can be used effectively to develop irrigation schedules.In conclusion,we can conclude that the application of RW can result in saving CW,improving to-mato quality,and increasing productivity without any negative effect on the investigated soil properties and that when used in conjunction with APRI,it can result in increasing IWUE.The APRI（70%ETc）under SDI,along with RW under the greenhouse,leads to preserving fresh water,as well as reducing the irrigation water amounts.It also serves as a safety option by reducing the physical contact between the wastewater,crops,and humans.Environment control is another contribution of this work,as against open fields application of reclaimed wastewater.