![]() ![]() Studies of human influences are ongoing in many areas, but are in their early stages of investigation. The involvement of human activities in the HAB expansion suggests that policy decisions leading to bloom mitigation are needed at several levels, but sound scientific evidence is needed to justify these actions. Florida red tides are naturally occurring events that are increasing in. Blue-green algae are a naturally occurring type of bacteria that is common in Floridas freshwater environments but can also be found in some marine. However, according to recent studies, this event occurring more frequently. However, the fact that part of the expansion is attributable to improved scientific capabilities should not temper our concern. Red tides tend to bloom and subside rapidly, depending upon changes in wind. Red tide is a natural occurrence that goes way back to the 1800s. At high concentrations, the organisms may discolor the water, sometimes red, light or dark green, brown. In Florida and the Gulf of Mexico, the species that causes most red tides is Karenia brevis, often abbreviated as K. The frequencies of red tides and of hypoxia per 96 months are both expressed as percentages. A red tide, or harmful algal bloom, is a higher-than-normal concentration of a microscopic alga (plantlike organism). The graph above, provided by former Cal Poly undergraduate. The red bar indicates the presence of the phytoplankton dinoflagellate called Akashiwo sanguinea, which is believed to be the culprit for the recent red tide. The global expansion of HAB phenomena is also in part a reflection of improved monitoring and detection capabilities. The red tide and hypoxia are defined as the case to detect Chl- a concentration 50 g L 1, and DO concentration < 2 mg L 1, respectively. The graph shown above shows proportions of phytoplankton species present in samples from Morro Bay from August 2 to August 23. Whatever the mechanisms, coastal regions throughout the world are now subject to an unprecedented diversity and frequency of HAB events. In some places, red tides are a natural occurrence due to a sudden increase in nutrients from coastal upwelling. The causes behind this expansion are debated, with possible explanations ranging from natural mechanisms of species dispersal to a host of human-related phenomena such as pollution and climatic shifts. ![]() Many countries are faced with an array of toxic or harmful species and impacts, as well as disturbing trends of increasing incidence and geographic expansion of blooms, increased impacts to fisheries resources, and higher economic losses. Several decades ago relatively few countries appeared to be affected by HABs, but now most coastal countries are threatened, in many cases over large geographic areas and by more than one harmful or toxic species.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |