Biogeochemical CyclesBiogeochemical Cyclesandand
Energy FlowEnergy Flow
Two Secrets of Survival: Energy Flow Two Secrets of Survival: Energy Flow and Matter Recycleand Matter Recycle
An ecosystem An ecosystem survives by a survives by a combination of combination of energy flow and energy flow and matter recycling.matter recycling.
Figure 3-14Figure 3-14
Fig. 3-14, p. 61
Abiotic chemicals(carbon dioxide,
oxygen, nitrogen, minerals)
Heat
Heat
Heat
Heat
Heat Solarenergy
Consumers(herbivores, carnivores)
Producers(plants)
Decomposers(bacteria, fungi)
The Water CycleThe Water Cycle
Figure 3-26Figure 3-26
Fig. 3-26, p. 72
PrecipitationPrecipitation
Transpiration
Condensation
Evaporation
Ocean storage
Transpiration from plants
Precipitation to land
Groundwater movement (slow)
Evaporation from land Evaporation
from ocean Precipitation to ocean
Infiltration and Percolation
Rain clouds
RunoffSurface runoff
(rapid)
Surface runoff (rapid)
The Carbon Cycle:The Carbon Cycle:Part of Nature’s ThermostatPart of Nature’s Thermostat
Effects of Human Activities Effects of Human Activities on Carbon Cycleon Carbon Cycle
We alter the We alter the carbon cycle by carbon cycle by adding excess COadding excess CO22 to the atmosphere to the atmosphere through:through: Burning fossil fuels.Burning fossil fuels. Clearing vegetation Clearing vegetation
faster than it is faster than it is replaced.replaced.
Figure 3-28Figure 3-28
Fig. 3-28, p. 74
CO
2 em
issi
on
s fr
om
fo
ssil
fu
els
(bil
lio
n m
etri
c to
ns
of
carb
on
eq
uiv
alen
t)
Year
Lowprojection
Highprojection
The Nitrogen Cycle: The Nitrogen Cycle: Bacteria in ActionBacteria in Action
Figure 3-29Figure 3-29
Fig. 3-29, p. 75
Gaseous nitrogen (N2)in atmosphere
Ammonia, ammonium in soil Nitrogen-rich wastes,remains in soil
Nitrate in soil
Loss byleaching
Loss byleaching
Nitrite in soil
Nitrification
Nitrification
Ammonification
Uptake by autotrophsUptake by autotrophsExcretion, death,
decomposition
Loss bydenitrification
Food webs on land
Fertilizers
Nitrogen fixation
The Phosphorous CycleThe Phosphorous Cycle
Figure 3-31Figure 3-31
Fig. 3-31, p. 77
Dissolvedin Ocean
Water
Marine Sediments Rocks
uplifting overgeologic time
settling out weatheringsedimentation
LandFoodWebs
Dissolvedin Soil Water,Lakes, Rivers
death,decomposition
uptake byautotrophs
agriculture
leaching, runoff
uptake byautotrophs
excretion
death,decomposition
mining Fertilizer
weathering
Guano
MarineFoodWebs
Food ChainFood Chain
Food WebFood Web
Ecological PyramidsEcological Pyramids
Ecological PyramidsEcological Pyramids
Ecological PyramidsEcological Pyramids