<P> The Intergovernmental Panel on Climate Change concluded that "a sustainable forest management strategy aimed at maintaining or increasing forest carbon stocks, while producing an annual sustained yield of timber fibre or energy from the forest, will generate the largest sustained mitigation benefit". Sustainable management practices keep forests growing at a higher rate over a potentially longer period of time, thus providing net sequestration benefits in addition to those of unmanaged forests . </P> <P> Life expectancy of forests varies throughout the world, influenced by tree species, site conditions and natural disturbance patterns . In some forests carbon may be stored for centuries, while in other forests carbon is released with frequent stand replacing fires . Forests that are harvested prior to stand replacing events allow for the retention of carbon in manufactured forest products such as lumber . However, only a portion of the carbon removed from logged forests ends up as durable goods and buildings . The remainder ends up as sawmill by - products such as pulp, paper and pallets, which often end with incineration (resulting in carbon release into the atmosphere) at the end of their lifecycle . For instance, of the 1,692 MegaTonnes of carbon harvested from forests in Oregon and Washington (U.S) from 1900 to 1992, only 23% is in long - term storage in forest products . </P> <P> One way to increase the carbon sequestration efficiency of the oceans is to add micrometre - sized iron particles in the form of either hematite (iron oxide) or melanterite (iron sulfate) to certain regions of the ocean . This has the effect of stimulating growth of plankton . Iron is an important nutrient for phytoplankton, usually made available via upwelling along the continental shelves, inflows from rivers and streams, as well as deposition of dust suspended in the atmosphere . Natural sources of ocean iron have been declining in recent decades, contributing to an overall decline in ocean productivity (NASA, 2003). Yet in the presence of iron nutrients plankton populations quickly grow, or' bloom', expanding the base of biomass productivity throughout the region and removing significant quantities of CO from the atmosphere via photosynthesis . A test in 2002 in the Southern Ocean around Antarctica suggests that between 10,000 and 100,000 carbon atoms are sunk for each iron atom added to the water . More recent work in Germany (2005) suggests that any biomass carbon in the oceans, whether exported to depth or recycled in the euphotic zone, represents long - term storage of carbon . This means that application of iron nutrients in select parts of the oceans, at appropriate scales, could have the combined effect of restoring ocean productivity while at the same time mitigating the effects of human caused emissions of carbon dioxide to the atmosphere . </P> <P> Because the effect of periodic small scale phytoplankton blooms on ocean ecosystems is unclear, more studies would be helpful . Phytoplankton have a complex effect on cloud formation via the release of substances such as dimethyl sulfide (DMS) that are converted to sulfate aerosols in the atmosphere, providing cloud condensation nuclei, or CCN . But the effect of small scale plankton blooms on overall DMS production is unknown . </P>

Why is biomass a temporary sink for co2