Effects of changing salinity on the ecology of the marine environment

Smyth, Katie; Elliott, Mike

Abstract

Changing salinity is a master factor in the distribution of both marine and estuarine species and is limiting to freshwater organisms; hence salinity is fundamental in modifying aquatic ecosystem assemblage structure and functioning. The effects of changing salinity on the ecology of different habitats is driven ultimately by the underlying physiology and tolerances of organisms and their ability to cope with salinity fluctuations on both long and short time scales. Estuarine species are often euryhaline, adapted to tolerate fluctuating salinity, whereas many marine species are stenohaline and limited by their narrow range of physiological tolerance. For estuarine species, lowered salinities may be a subsidy, i.e. benefiting the organisms by reducing competition, whereas for non-tolerant species they are a stressor. Salinities at the margins or outside the tolerance range of particular species will prevent their occurrence, change their behaviour, or limit reproduction and germination, reducing their fitness for survival in that environment. Salinity can act synergistically or antagonistically with other environmental stressors, producing a dynamic and changing environment. Anthropogenic activities and effluents can modify local salinity regimes and their effects depend on the assimilative capacity of both the area and the species. This chapter discusses such effects of changing salinity at the species, community, and ecosystem levels of biological organization. It also explores salinity change as an environmental perturbation in terms of various saline ecosystems worldwide, from ice melt/formation in polar regions through to man-made salt pans and desalination plants.

Citation

Smyth, K., & Elliott, M. (2016). Effects of changing salinity on the ecology of the marine environment. In M. Solan, & N. Whiteley (Eds.), Stressors in the Marine Environment: Physiological and ecological responses; societal implications (161-174). Oxford: Oxford University Press. https://doi.org/10.1093/acprof%3Aoso/9780198718826.003.0009

• Publication Date: 2016
• Deposit Date: May 28, 2019
• Pages: 161-174
• Book Title: Stressors in the Marine Environment: Physiological and ecological responses; societal implications
• Chapter Number: 9
• ISBN: 9780198718826
• DOI: https://doi.org/10.1093/acprof%3Aoso/9780198718826.003.0009
• Keywords: Salinity; Physiological tolerance; Species; Community; Ecosystem; Competition; Euryhaline; Stenohaline
• Public URL: https://hull-repository.worktribe.com/output/1856347
• Publisher URL: https://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198718826.001.0001/acprof-9780198718826-chapter-9