Spatial Distribution of Salinity and Sodicity in Arid Climate Following Long Term Brackish Water Drip Irrigated Olive Orchard
| Autor: | John Rohit Katuri, Gilboa Arye, Pavel Trifonov |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
0106 biological sciences
Irrigation olives trees Geography Planning and Development Drip irrigation Aquatic Science 01 natural sciences Biochemistry salinity sodicity Sodium adsorption ratio sub surface drip irrigation (SDI) Water Science and Technology Brackish water Desert climate 04 agricultural and veterinary sciences Arid Olive trees Salinity Agronomy 040103 agronomy & agriculture arid region 0401 agriculture forestry and fisheries Environmental science brackish water 010606 plant biology & botany |
| Zdroj: | Water Volume 11 Issue 12 |
| ISSN: | 2073-4441 |
| DOI: | 10.3390/w11122556 |
| Popis: | The availability of brackish groundwater in the Negev Desert, Israel has motivated the cultivation of various salinity tolerant crops, such as olives trees. The long term suitability of surface drip irrigation (DI) or subsurface drip irrigation (SDI) in arid regions is questionable, due to salinity concerns, in particular, when brackish irrigation water is employed. Nevertheless, DI and SDI have been adopted as the main irrigation methods in olive orchards, located in the Negev Desert. Reports on continued reduction in olive yields and, essentially, olive orchard uprooting are the motivation for this study. Specifically, the main objective is to quantify the spatial distribution of salinity and sodicity in the active root-zone of olive orchards, irrigated with brackish water (electrical conductivity EC = 4.4 dS m&minus 1) for two decades using DI and subsequently SDI. Sum 246 soil samples, representing 2 m2 area and depths of 60 cm, in line and perpendicular to the drip line, were analyzed for salinity and sodicity quantities. A relatively small leaching-zone was observed below the emitters depth (20 cm), with EC values similar to the irrigation water. However, high to extreme EC values were observed between nearby emitters, above and below the dripline. Specifically, in line with the dripline, EC values ranged from 10 to 40 dS m-1 and perpendicular to it, from 40 to 120 dS m&minus 1. The spatial distribution of sodicity quantities, namely, the sodium adsorption ratio (SAR, (meq L&minus 1)0.5) and exchangeable sodium percentage (ESP) resembled the one obtained for the EC. In line with the dripline, from 15 to 30 (meq L&minus 1) 0.5 and up to 27 %, in perpendicular to the drip line from 30 to 60 (meq L&minus l)0.5 and up to 33 %. This study demonstrates the importance of long terms sustainable irrigation regime in arid regions in particular under DI or SDI. Reclamation of these soils with gypsum, for example, is essential. Any alternative practices, such as replacing olive trees and the further introduction of even high salinity tolerant plants (e.g. jojoba) in this region will intensify the salt buildup without leaving any option for soil reclamation in the future. |
| Databáze: | OpenAIRE |
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