All About Algae

What are algae?
Algae are simple, aquatic, plant-like organisms that do not have true roots, stems and leaves. Many are single-celled so can only be seen using a microscope, while others grow in filaments or mats that are quite conspicuous. Algae have chlorophyll and can make their own food through the process of photosynthesis.

Why are algae important?
Algae produce oxygen as a waste product of photosynthesis.

Cyanobacteria are amongst the most ancient forms of life and they have been contributing oxygen to the world’s atmosphere for the last three billion years.

Cyanobacteria are able to fix nitrogen from the atmosphere. All organisms require large amounts of nitrogen for their metabolism and cyanobacteria play an important role in making atmospheric nitrogen available in nutrient cycles.

Algae help to ‘purify’ water by absorbing nutrients and heavy metals from streams and rivers.

Algae are the basis of most aquatic food webs. They are food for many small aquatic invertebrates, and in turn, these small creatures are food for larger animals such as fish.

Algae also provide important habitats for invertebrates and fish. Without organisms that can capture energy from the sun by photosynthesis, none of the higher organisms would exist.

Algae can be valuable indicators of environmental quality. Many are sensitive to changes in pH, in nutrient levels or in temperature. Monitoring species abundance and composition can be useful to identify changes in water quality caused by changes in surrounding land use.
(From the New Zealand Dept. of Conservation page on algae.)

Algae Identification Field Guide - from Canada

Cyanobacteria (Blue-Green Algae)

These materials and web sites will inform you about cyanobacteria.

Cyanobacteria (Toxic Algae) Fact sheet. A consice overview of toxic algae in the Eel River basin.

Frequently Asked Questions and Resources for Harmful Algal Blooms and Cyanobacterial Toxins. US Environmental Protection Agency Region 9.

California Public Health Cyanobacteria Website  Information and links to other sites that will be helpful to the public and to local, regional, and state public health and environmental health officials

Cyanosite A Website for research on Cyanobacteria. Lots of information about all species of cyanobacteria. Supported by Biological Sciences at Purdue University and by Wichita State University

Cyanobacteria: Life History and Ecology.  From U.C. Berkeley

Images and Videos of Cyanobacteria At the Cyanosite website.

Photo Credit:  Paula Furey