Azolla videos   Azolla Plant Azolla growing in a pond creaates a pleasing green carpet....azolla fern Azolla This is how the azzola pond was prepared...Azolla Biofertilizer Azoola Cultivation Adding value to the residue from biogas plants Vivekananda Kendra - Natural Resources Development Project (VK- NARDEP) has sold and installed 2,000 biogas plants in southern Tamil Nadu, India, to provide clean biogas for household cooking and fertiliser from the biogas residue. The southern part of Tamil Nadu is hot and humid. Most people work in agriculture and grow rice, sugar cane, mangoes, coconuts and a range of vegetables. The biogas plants sold by VK- NARDEP use cattle manure to produce biogas which saves fuelwood, allows cleaner cooking and gives a healthier environment, with reduced air pollution and fly-borne diseases. VK- NARDEP has also recognised the significant potential of the output residue from biogas plants. This is normally used directly as a fertiliser and weed suppressor which gives significant benefits in a rural agricultural environment. The value of the residue can be increased by using it to grow Azolla, a nitrogen-fixing fern used as animal fodder or green manure. Alternatively, the residue can be made into an improved fertiliser using vermin-composting techniques. The financial savings from avoiding the purchase of wood and chemical fertiliser allow the cost of a biogas plant to be paid back within two to three years.