Solar saltworks are facilities where NaCl salt is produced through the natural evaporation of seawater or brine using sunlight and wind. These saltworks typically consist of large, shallow ponds or pans that allow water to evaporate slowly, leaving behind crystallized salt. This method is energy-efficient and environmentally friendly, as it relies on natural solar energy rather than industrial processes. Solar saltworks are commonly found in warm, arid coastal regions where evaporation rates are high.
Saltworks are not just to be considered as a kind of factory for salt production, but also as an ecosystem. Appropriate management ensures that each area develops a specific and interactive flora and fauna, to avoid hydrobiological imbalances that could negatively affect salt production in terms of salt quantity and/or quality.
Phytoplankton in saltworks often form monocultures, influenced by salinity and other conditions, which impact pond color and evaporation rates. High algae density boosts evaporation by absorbing more sunlight. In coastal areas with highly oligotrophic intake waters, additional fertilization of evaporation ponds is necessary to promote adequate algal blooms.
Artemia, the main zooplankton in saltworks, plays a crucial role in maintaining balance. It controls algae populations through grazing, preventing overgrowth that could hinder salt quality. Excess algae, especially in high salinity, can delay gypsum precipitation and reduce salt purity.
When brine shrimp die, their decomposing bodies provide a nutrient-rich substrate for halophilic microorganisms. These microbes produce red pigments that give the water its characteristic coloration, which enhances heat absorption and boosts evaporation. Additionally, their activity reduces water viscosity, promoting the formation of larger salt crystals and improving overall salt quality.
Effective Artemia management is often essential for maintaining optimal salt production conditions. This includes controlling excessive algal blooms by inoculating ponds with nauplii hatched from commercially available cysts or by transplanting Artemia biomass within the farm or from nearby saltworks.
It is understandable that the primary commercial focus of solar salt farmers is the production of high-quality salt, with Artemia often regarded as a secondary byproduct. Moreover, the conditions within salt farms are typically not optimized for Artemia cultivation. However, adjacent areas could be developed specifically for efficient Artemia biomass and/or cyst production. By managing brine inputs into these Artemia ponds and directing brine outputs back into the main evaporation system, valuable opportunities for integrated business models and enhanced profitability could emerge.