Diseases caused by Sclerotinia spp., generally known as 'white mold', can affect hundreds of plant species including many important crops. The pathogens are favored by cool, moist conditions, but show surprisingly broad ecological distributions. 1 Several other Sclerotinia species cause diseases other than white mold.
Oxygen dissolves into water from two sources: the atmosphere and from plants in the water. The primary source of oxygen for a pond is from microscopic algae (phytoplankton) or submerged plants.In the presence of sunlight, these produce oxygen through photosynthesis and release this oxygen into the pond water.xygen dissolves in water at very low concentrations. Our atmosphere is 20% oxygen or 200,000 ppm but seldom will a pond have more than 10 ppm oxygen dissolved in itsâ water. Dissolved oxygen concentrations below 3 ppm stress most warmwater species of fish and concentrations below 2 ppm will kill some species.
Scientists agree that thereâs oxygen from ocean plants in every breath we take. Most of this oxygen comes from tiny ocean plants â called phytoplankton â that live near the waterâs surface and drift with the currents.Like all plants, they photosynthesize â that is, they use sunlight and carbon dioxide to make food. A byproduct of photosynthesis is oxygen.Scientists believe that phytoplankton contribute between 50 to 85 percent of the oxygen in Earthâs atmosphere. They arenât sure because itâs a tough thing to calculate. In the lab, scientists can determine how much oxygen is produced by a single phytoplankton cell.cientists agree that thereâs oxygen from ocean plants in every breath we take. Most of this oxygen comes from tiny ocean plants â called phytoplankton â that live near the waterâs surface and drift with the currents.