The success story of irrigation against salinity in Violada, NE Spain

Abstract

In the early 20th century, when extensive areas of land were transformed from rainfed to irrigated agriculture, there was a severe lack of scientific and technical literature available on the effects of applying water to saline soils. This was the case of the Violada Irrigation District located in a semiarid region of NE Spain whose transformation started in the 1940s. We discuss the use of agronomical expertise and the limited knowledge of soils available prior to the transformation, the favorable and unfavorable scenarios encountered during the transformation, and the final success of irrigation despite the initial soil salinization and water logging. We attribute the technical success to the fact that gypsum is common in the soils and geological materials, and to the continued drainage efforts. Failures in the irrigation of saline lands are a frequent subject of discussion in the scientific literature; contrariwise, we present the history of a successfully irrigated district after 70 years.

A Legacy of Quantitative and Qualitative Data for the Irrigated Violada Area and Conterminous Lands in Aragon, Spain

“…Several studies were conducted involving the ecology of Violada, such as those mentioned by [9]. More recent studies have been devoted to the soil and water salinity of Violada, as is the case in [10][11][12][13][14][15]. A comparison of these studies against the data contained in the IRYDA report [1] can highlight the decadal effects of irrigation, as was done for another irrigation area [16].…”

The vanishing legacy of soil salinity data from irrigated districts: A case study from Spain and a call for action

“…These results might be improved or modified if a fully readable copy of the 1975 IRYDA report can be found. Another example, based on heritage documents from 1978, records and analyzes the success in desalinating an irrigated area of around 5000 ha (Herrero and Castañeda, 2018) The lack of data on the temporal changes in soil salinity in the irrigated districts makes possible the present frequent misuse of the term salinization, with some irrigated districts labeled in the media or in environmental reports as "salinized". This misused label is commonly unwarranted or, at best, founded upon speculations on indirect symptoms, and without providing either evidence or measurements of the salt content at two different times.…”

Water Balance and Nitrate and Salt Exports from a Saline–Sodic Irrigation District in Castelflorite (Huesca, NE Spain)

“…Newly modernized irrigation communities offer a suitable scenario to evaluate the impact of aforementioned transformation on the use of water and to assess its effects on the quantity and quality of water. An example of a long-term monitoring of one of those irrigation communities, that of La Violada, has been reported in [20][21][22][23][24][25][26][27].…”

“…However, there are cases of failure in the sustainability of irrigation in some cultivated areas, and a common reason for such failures is soil salinity or/and sodicity, either natural or induced by irrigation transformation [27]. Although salinity problems have been reported in the case of La Violada and other areas of RAAID, a very serious case of saline-sodic soils occurs in the San Pedro de Castelflorite Irrigation Community, chosen for the study presented herein.…”