Adaptation to saline environments by halophytes may take the form of salt tolerance (see halotolerance) or salt avoidance. Plants that avoid the effects of high salt even though they live in a saline environment may be referred to as facultative halophytes rather than 'true', or obligatory, halophytes.
For example, a short-lived plant species that completes its reproductive life cycle during periods (such as a rainy season) when the salt concentration is low would be avoiding salt rather than tolerating it. Or a plant species may maintain a 'normal' internal salt concentration by excreting excess salts through its leaves or by concentrating salts in leaves that later die and drop off. (Whether the latter is tolerance or avoidance may depend on one's point of view...)
Related information: biosalinity, halophile.
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