Abstract

PONCE, Víctor M.; ONATE-VALDIVIESO, Fernando  and  COBOS-AGUILAR, Raúl. The right of nature to dispose of its salts. Tecnol. cienc. agua [online]. 2018, vol.9, n.3, pp.1-28.  Epub Nov 24, 2020. ISSN 2007-2422.  https://doi.org/10.24850/j-tyca-2018-03-01.

Ions of sodium and calcium are produced by lithospheric disintegration in quantities far exceeding those that could possibly be assimilated by the terrestrial biosphere. In exorheic drainages, the resulting waste has been (and is being) transported to the ocean by streams and rivers. In endorheic drainages, it has collected in the interior of continents, producing closed salt basins. In general, exorheism is preferable to endorheism because it leads to healthier and more diverse ecosystems. Irrigation converts runoff into evaporation, reducing the amount of water available for salt flushing. At the same time, particularly in arid and semiarid regions where it is most needed, irrigation mobilizes new salts through the additional biodegradation of geologically young soils. At the limit, when all runoff is sequestered and converted to evaporation, there is no water left to carry the salts to the ocean. As the system is gradually driven towards this limit, it becomes unsustainable, not for lack of water to support the vegetation, but for lack of water to flush the salts. In accordance with hydrologic science, we posit that nature had a different plan: on average, two-thirds of the available water for the ecosystem and the remaining one-third for flushing all salts, regional and new. The misguided strategy of retaining all runoff, on the grounds that it constitutes "precious" water, could only lead to the eventual conversion of peripheral continental basins into artificial, salt-infested basins.

Keywords : Salt; salinization; right of nature; salt balance.