Ice algae terrestrial ice algae occur in freshwater systems, the species composition differs greatly from that of sea ice algae. These communities are significant in that they often change the color of glaciers and ice sheets, impacting the reflectivity of the ice itself. Microbial life in sea ice is extremely diverse, and includes abundant algae, bacteria and protozoa. Algae in particular dominate the sympagic environment, with estimates of more than 1000 unicellular eukaryotes found to associate with sea ice in the Arctic. Species composition and diversity vary based on location, ice type, and irradiance. In general, pennate diatoms such as "Nitschia frigida"
Mycorrhiza helper bacteria Mycorrhiza helper bacteria Mycorrhiza helper bacteria (MHB) are a group of organisms that form symbiotic associations with both ectomycorrhiza and arbuscular mycorrhiza. MHBs are diverse and belong to different bacterial phyla including both gram-negative and gram-positive bacteria. Some of the most common types are "Pseudomonas" and "Streptomyces". MHBs have specific interactions with fungi, but not with the plants. MHB enhance mycorrhizal function, increase mycorrhizal growth, provide nutrients to the fungus and plant, improve soil conductance, select to aid pathogens, and help promote defense mechanisms. MHBs consist of a diverse group of organisms, often gram-negative and gram-positive bacteria. Most of the