The Great Salt Lake Is Experiencing Hyper Salinity, Posing a Serious Threat to the Ecosystems and Economies [Study]

The Great Salt Lake is becoming saltier as it runs out of fresh water.

According to Wayne Wurtsbaugh of the Quinney College of Natural Resources Watershed Sciences, the lake is losing sources of freshwater input due to agriculture, urban sprawl, and drought, and the drawdown is causing salt concentrations to soar beyond the tolerance of brine shrimp and brine flies.

The Great Salt Lake on the path to hyper-salinity

(Photo : Ruston Jones/Unsplash)

The ecological and economic repercussions of this transition are complicated and unprecedented, and researchers are keeping a careful eye on another pressured saline lake, Lake Urmia in Iran, for indications on what to anticipate next, as per ScienceDaily.

According to a recent study by Wurtsbaugh and Somayeh Sima of Tarbiat Modares University in Tehran, this "sister lake" presents apparent, and worrisome, parallels to the demise of the Great Salt Lake.

Both lakes' histories have followed similar paths but at differing rates.

As less freshwater flows into these lakes from connecting rivers and streams, natural salts become increasingly concentrated in the water.

Native brine flies and brine shrimp can withstand salt, but when saline levels reach severe amounts - sometimes approaching saturation - even animals and plants accustomed to saltwater conditions struggle.

This implies that millions of migrating birds that rely on these food sources will suffer, starve, or flee.

Expanding urban populations in northern Utah have claimed more freshwater for crops, lawns, and faucets throughout the decades, progressively increasing stress on the ecology.

A 20-year drought is now pushing salt levels further higher, according to Wurtbaugh.

A causeway separates the Great Salt Lake into two sections.

With no freshwater supplies, the lake's northern arm (Gunnison Bay) has become the saltiest, with levels approaching saturation.

A salt transfer into the north arm has allowed the south arm (Gilbert Bay) to maintain salinity levels that allow brine shrimp and brine flies to survive.

However, salinities in the south are increasingly reaching levels that are stressful for even the most resilient species.

The Great Salt Lake and Lake Urmia in Iran were previously strikingly comparable in terms of size, depth, salinity, and location.

High rates of urban expansion drove demand for irrigated agriculture and human needs, placing the environment under great stress.

Gilbert Bay in the north arm of Great Salt Lake has reached an incredible 330 grams per liter (27% salt), and brine shrimp are practically gone, ending the $70 million brine shrimp industry's harvest there, according to Wurtsbaugh.

Shrimp harvesting in the south arm is now endangered by rising salinities.

Brine shrimp prefer salt levels between 75 and 160 grams per liter.

Brine fly larvae can withstand higher salt concentrations, but even this robust species feels the pressure when conditions are so extreme.

Brine fly larvae shrink at greater salt levels, indicating ecological stress, according to Wurtsbaugh.

The combined extinction of these two creatures might have disastrous ecological effects on migrating bird numbers and the lake's economy.

Managers may still control the flow of salt from the north to the south arms of the lake by constructing an underwater berm at a gap in the causeway.

This flow is utilized to regulate the competing requirements of the lake's mineral extraction enterprises and the brine shrimp harvesting sector.

However, if water development and climate change cause significant losses in water levels, even that choice will become restricted, according to Wurtsbaugh.

Also Read: Great Salt Lake Is 'In Peril' as Its Level Drops to Its Lowest Point Ever for the Second Consecutive Year

Recognizing Salinity

Changes in land use, seasonal fluctuations in our weather, and long-term climatic changes may all have an impact on surface water, groundwater, the flows that connect them, and the levels of salt they contain, as per The Government of Western Australia.

The amounts of salts in water or soils are referred to as "salinity."

Salinity is categorized into three types based on its cause: primary salinity (also known as natural salinity), secondary salinity (also known as dryland salinity), and tertiary salinity (also called irrigation salinity).

Small quantities of dissolved salts in natural waterways are essential for aquatic plant and animal life; increasing levels of salinity change how the water may be utilized, but even the most hypersaline water can be used for some purposes.

Natural processes, such as the deposit of salt from rainfall over many thousands of years or the weathering of rocks, generate primary salinity.

When rain falls on a landscape, some evaporates off the soil, plant surfaces, and water bodies, while others soak into the soil and groundwater and move into streams, rivers, lakes, or oceans.

Small quantities of salt carried by rain can accumulate in soils (particularly clayey soils) and flow into groundwater over time.

Secondary salinity occurs when groundwater levels increase, bringing salt from the "primary" salinity processes to the surface.

This is produced by the removal of perennial (long-lived) vegetation in arid environments, i.e. locations where salt accumulates in the soil profile and groundwater over time.

When vegetation is removed, like in the Western Australian Wheatbelt, the quantity of water lost from the landscape through plants is substantially decreased.

Rather, more water enters the groundwater, raising groundwater levels.