Is biomass of filamentous green algae Cladophora spp. (Chlorophyta, Ulvophyceae) an unlimited cheap and valuable resource for medicine and pharmacology? A review

Filamentous green algae Cladophora spp. are cosmopolitans inhabiting waters with different salinity, from freshwater to hypersaline. Eutrophication of marine and inland waters results in the huge development of filamentous green algae, which reach high biomass and occupy large areas in different water bodies. This leads to the strong negative effect on the species richness of communities, significantly reduces the aesthetic value of coastal waters, hampers the recreational use of beaches and the coastline, and complicates industrial water intake and coastal fishing. Harvesting and the use of Cladophora biomass can be an effective tool to remediate eutrophic waters. Cladophora spp. are also among the most promising subjects to use in the development of integrated multi-trophic aquaculture; there is a big potential to use it. Aquaculture is one of the potential uses. To plan the use of a resource, business needs to know the availability and quantity of the resource, the price of the resource, as well as for what benefit and how it can be used. This review summarizes and analyses existing data to answer these questions. Cladophora biomass can be used for food for humans, livestock, cultivated fish and shrimps, as fertilizers, in the energy sector (biogas and biodiesel), and different industries. The use of Cladophora in medicine and pharmacology is one of the most profitable promising ways to utilize the biomass. This review shows that Cladophora biomass is an unlimited, low cost and valuable resource for medicine and pharmacology

Daily Rhythms and Oxygen Balance in the Hypersaline Lake Moynaki (Crimea)

Field observations of the diurnal behavior of several parameters (oxygen concentration, chlorophyll fluorescence, photosynthetically active radiation (PAR), wind speed, temperature, suspended matter concentration, and zooplankton abundance) were conducted at three sites in the marine hypersaline lake Moynaki (Crimea). The diurnal course of PAR followed a bell-shaped form, with the maximum at 14:00 on the 15th and 16th of September 2021. The oxygen concentration varied over a wide range from 3.2 to 9.3 mg L−1, demonstrating a clear diurnal rhythm. From sunrise until about 17:30, it increased. Both the maximum and minimum values were marked on the site where there were Ruppia thickets. The daily rhythm of Chlorophyll a concentration was clearly expressed during the observation period, varying from 2.49 to 18.65 µg L−1. A gradual increase in the concentration of chlorophyll a began after 10:00 and lasted until about 2:30–3:00 of the next day. The daily production of oxygen during photosynthesis averaged 27.3 mgO L−1 day−1, and the highest values were noted at the windward site of 37.9 mgO L−1 day−1, and the lowest at the leeward site of 19 mgO L−1 day−1. The total respiration of the community per day was, on average, 15.9 mgO L−1 day−1. It averaged 63% of the primary production created. The contribution of animals to the total oxygen consumption of the community was small, averaging 5%

Salinity-Dependent Species Richness of Bacillariophyta in Hypersaline Environments

Hypersaline habitats are among the most polyextreme habitats on Earth, but they contain a rather large diatom species diversity. A review of the diatom species’ richness was made on three scales: 1. a separate lake in Crimea; 2. all hypersaline waters in Crimea; and 3. the world totality as a whole. In total, 51 species were found in Lake Chersonesskoye during sampling from 2004 to 2018. In ten Crimean hypersaline lakes, 91 species were noted in total. All diatom species found in the studied hypersaline water bodies of the world belong to 458 species, which is 2.7% of the total number of known species of Bacillariophyta. In all three scales, the similarity of the species’ composition between water bodies as well as studied periods was not found. Most of all the identified species were found only in one of the studied water bodies, and only 59 species (13% of the total list) were found in more than three water bodies. An analysis showed that no more than 40% of the species that exist in hypersaline waters have been identified on a global scale. The diatom shell nanostructure from hypersaline waters has specific peculiarities that may be valuable for some technological applications. The knowledge of diatoms in hypersaline waters not only has pure scientific importance but also covers some needs of bio- and nanotechnologies

Cladophora (Chlorophyta) как «инженер-эколог» в гиперсолёном озере Херсонесском: распределение диатомовых водорослей в структурированном пространстве растительных матов

Род Cladophora — один из крупнейших родов зелёных водорослей, представители которого встречаются во всех водоёмах мира. Кладофора организует среду обитания для разных групп организмов, в том числе для эпифитных одноклеточных водорослей. Цель работы — изучить вертикальное распределение диатомей в структурированном пространстве матов Cladophora и в донных отложениях гиперсолёного озера в Крыму. В вертикальном строении мата кладофоры различали плавучий и донный маты, каждый из которых имел характерную структуру. Всего в ходе данного исследования зарегистрированы 20 видов диатомовых водорослей из 12 родов. Общая численность диатомей и их биомасса на Cladophora (в расчёте на единицу сухой биомассы) и в донных отложениях (в расчёте на единицу сухой массы) варьировали в широком диапазоне. На кладофоре численность изменялась от 1,85 × 106 до 69,52 × 106 кл.·г−1, а биомасса — от 7,77 до 157,43 мг·г−1. В донных осадках численность варьировала от 6,05 × 106 до 16,87 × 106 кл.·г−1, биомасса — от 7,76 до 36,39 мг·г−1. Доля биомассы диатомовых водорослей в сырой массе всего мата Cladophora в среднем составила 1,06 %