Mapping of Land Suitability Evaluation for Surface and Under Pressure Irrigation by Geostatistic Methods on Upper Terrace of Aras River in ParsAbad-e-Moghan

Zohreh Bandalizadeh | Hossein Torabi Golsefidi

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URL :   http://research.shahed.ac.ir/WSR/WebPages/Report/PaperView.aspx?PaperID=159227
Date :  2021/10/20
Publish in :    هفدهمين کنگره علوم خاک ايران و چهارمين همايش ملي مديريت اب در مزرعه

Link :  https://civilica.com/doc/1312605/
Keywords :Parametric method, Irrigation capacity index, Suitability class for irrigation, kriging, Inverse distance weighting (IDW)

Abstract :

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One of the main priorities of the agriculture is the proper use of water and soil resources. Land suitability evaluation for irrigation was carried out based on the morphological, physical and chemical characteristics of 454 soil profiles on the 12500 hectares of the second development unit of Khoda-afarin. The study area was located on the upper terrace of Aras River in ParsAbad Township. Seven soil characteristics were used for calculation of irrigation capacity index (Ci) for three methods of surface, sprinkler and drip irrigation. The weighted average of the above soil characteristics were calculated up to 100 cm depth of soil profile by parametric method. Geostatical analysis and interpolation of soil properties were carried out by kriging and IDW, then their maps were prepared by ArcGIS10.1. Exponential models were fitted for all of Ci. The variography studies of indices showed that the spatial variability structure was not strong (r=0.65 to 0.75 and C0/C+C0=0.5 to 0.75). Root mean square error (RMSE) for IDW mapping was less than RMSE of Kriging. Mapping of Ci by inverse distance weighting (IDW) method showed that the suitability classes for surface irrigation were 4370 ha S1, 9172 ha S2, 2145 ha S3, 352 ha N1, and 17 ha N2 respectively. The suitability classes for sprinkler irrigation were 2246 ha S1, 7809 ha S2, 1018 ha S3, and 52ha N1 respectively. The suitability classes for drip irrigation were 929 ha S1, 9715 ha S2, 4168 ha S3, and 160 ha N1 respectively. The most important limiting factors for surface and sprinkler irrigation were soil texture, gypsum and slope, but for drip irrigation, they were soil texture, gypsum and calcium carbonate. The slope limitation had much less effect on drip irrigation

https://civilica.com/doc/1312605/