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Primary Productivity. Jason Broshear Katherine Echement Zach Moning Leo Sack. Photosynthesis. Photosynthesis. Respiration. Carbon Cycle. Greenhouse Effect. Primary Productivity. Phytoplankton. Phytoplankton. Single-celled plants Photosynthesis
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Primary Productivity Jason Broshear Katherine Echement Zach Moning Leo Sack
Phytoplankton • Single-celled plants • Photosynthesis • Lots of them – about half of plant biomass on the planet
Phytoplankton Distribution • Where is the most phytoplankton productivity?
Arctic and Southern Oceans • In high latitudes, most nutrients rarely used up • Limiting factor: dissolved iron • “Fertilize” these regions with iron, more productivity • Solution to global climate change??
Problems with Iron Fertilization • Zooplankton grazing also a limiting factor • Much added iron “lost” – affects on other ecosystems? • Limited effect on CO2 – most recycled in water, not sinking • Not economically feasible solution
Boreal Forest: Background • The northern boreal ecoregion accounts for about one third of this planet's total forest area. • Is considered one of the largest carbon sinks. • Most dominant tree species are conifers which are well-adapted to the harsh climate, and thin, acidic soils. • There are innumerable water bodies: bogs, fens, marshes, shallow lakes, rivers and wetlands, mixed in among the forest and holding a vast amount of water. • Fire is a crucial disturbance factor in the boreal ecoregion because it facilitates the destruction of old, diseased trees along with the pests that are associated with those trees. • Some trees such as aspen and jackpine actually require fires to stimulate their reproductive cycles. Furthermore, the nutrient-rich ash left behind helps fuel plant growth.
Grasslands: Background • Tropical grasslands (Savannas) and temperate • Savannas have wet and dry seasons - heavy rain and seasonal fires • Grasses are dominant, trees and large shrubs mostly absent • Large and small mammals, reptiles, birds, etc.
