Factors that cause the formation of Red Tides / Algal blooms Red tide is initiated by a combination of : - Natural factors (e.g. Algal blooms sometimes are natural phenomena, but their frequency, duration and intensity are increased by nutrient pollution. To simulate the occurrence of bacterial and algal blooms in the Dead Sea, we filled 5.6 m 3 outdoor ponds with mixtures of Dead Sea water and Mediterranean water, at different seasons, and studied the effect of salinity and of addition of glycerol, glucose and different concentrations of phosphate on the rate and extent of bacterial and algal growth. What Causes Algae in Lakes and Ponds? Sometimes, however, their roles are much more sinister. These types of algae blooms are referred to as Harmful Algal Blooms or HABs, and their occurrence is on the rise in Minnesota lakes, streams and wetlands. Algal blooms may occur in freshwater as well as marine environments. In other cases, HABs may be linked to 'overfeeding.' This recent increase in the occurrence of HABs has been attributed to increasing anthropogenic activities and their interaction with factors known to contribute to the growth of cyanobacterial blooms. Such physical factors may also be key to the geographical inconsistency in the influence of anthropogenic nutrient enrichment on HABs, as rates of lateral exchange, mixing, or dispersion within and between water bodies differ (Gowen et al., 2012). Algae is a growing concern plaguing many lake and pond owners — in fact, algae outbreaks increased by 18 percent between 2018 and 2019 alone. Algae are always present in natural bodies of water like oceans, lakes, and rivers, but only a few types can produce toxins. Intensified land-use, sewage discharge, and climate change have likely favored disproportionate development of harmful algae in freshwaters. In this guide, we’ll discuss the causes of algae in ponds and lakes, as well as the hazards associated with algal blooms. Even when visible signs of a bloom are absent, however, algal toxins may … light intensity, temperature, salinity, nutrients, trace elements, water flow and motility of algal cells) - Anthropogenic factors (e.g. The excessive algal growth, or algal bloom, becomes visible to the naked eye and can be green, blue-green, red, or brown, depending on the type of algae. An algal bloom or marine bloom or water bloom is a rapid increase in the population of algae in an aquatic system. While we know of many factors that may contribute to HABs, how these factors come together to create a 'bloom' of algae is not well understood. Summary. Hydrodynamics may act in a range of ways. Studies indicate that many algal species flourish when wind and water currents are favorable. A small percentage of algal species produce toxins that can kill fish, mammals, and birds, and may cause human illness. discharge of organic or nutrient-enriched matters) that encourage the rapid and massive growth of algae. 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