Chapter 52 Biomes and Ecology 4/20/2018AP Biology Minzenmayer

Organismal ecology Population ecology Community ecology Ecosystem Fig. 52-2 Organismal ecology Population ecology Community ecology Ecosystem ecology Landscape ecology Global ecology

Ecology Scientific study of interactions between organisms and environment Involves Biotic factors Include all living parts of ecosystem including behavior Predator/prey; parasite/host etc… Abiotic factors Nonliving, chemical and physical components of ecosystem Temperature, water, salinity, sunlight and soil AP Biology Minzenmayer

Does Feeding by Sea Urchins Limit Seaweed Distribution? Hypothesis? 100 Both limpets and urchins removed 80 Sea urchin Only urchins removed 60 Seaweed cover (%) Limpet If sea urchins are a limiting biotic factor, then more seaweed should invade an area from which sea urchins have been removed. 40 Experiment: If sea urchins are a limiting biotic factor, then more seaweed should invade an area from which sea urchins have been removed. Results: removing both limpets and urchins or removing only urchins increased seaweed cover dramatically Almost no seaweed grew in areas where both urchins and limpets were present or where only limpets were removed Conclusions Removing both limpets and urchins resulted in the greatest increase in seaweed cover, indicating that both species have some influence on seaweed distribution. But since removing only urchins greatly increased seaweed growth while removing only limpets had litte effect, concluded that sea urchins have a much greater effec t than limpets in limiting seaweed distribution Only limpets removed 20 Control (both urchins and limpets present) August 1982 February 1983 August 1983 February 1984

Fig. 52-9

Fig. 52-5 Kangaroos/km2 0–0.1 0.1–1 1–5 5–10 10–20 > 20 Limits of distribution Interactions between organisms and environment limit distribution of species AP Biology Minzenmayer

Factors Limiting Geographic Distribution Why is species X absent from an area? Yes Area inaccessible or insufficient time Does dispersal limit its distribution? No Yes Does behavior limit its distribution? Habitat selection Factors Limiting Geographic Distribution No Do biotic factors (other species) limit its distribution? Yes Predation, parasitism, competition, disease No Chemical factors Water, oxygen, salinity, pH, soil nutrients, etc. Do abiotic factors limit its distribution? Temperature, light, soil structure, fire, moisture, etc. Physical factors

Climate Prevailing weather conditions in an area Includes Temperature* Sunlight Wind Precipitation* Macroclimate patterns Global, regional or local Microclimate patterns Small scale variations Under log AP Biology Minzenmayer

Latitudinal Variation in Sunlight Intensity 90ºN (North Pole) 60ºN Low angle of incoming sunlight 30ºN 23.5ºN (Tropic of Cancer) Sun directly overhead at equinoxes 0º (equator) 23.5ºS (Tropic of Capricorn) 30ºS Kcurved shape of earth causes latitudinal variation in intensity of sunlight Becaue sunlight strikes tropics more directly, more heat and light per unit of surface area are delivered there At higher latitudes, sunlight strikes earth at an oblique angle and light is more diffuse on earth’s surface Low angle of incoming sunlight 60ºS 90ºS (South Pole) Atmosphere AP Biology Minzenmayer

Seasonal Variation in Sunlight Intensity March equinox 0º (equator) June solstice 30ºS June solstice—northern hemisphere tilts toward sun and has longest day and shortest night Sourthern hemisphere tilts away from sun and has shortest day and longest night March equinox Equator faces sun directly; neither pole tilts toward sun; all regions on earth experience 12 hours day and 12 hours night December solstice Northern hemisphere tilts away from sun and has shortest day and longest hight Southern hemisphere tilts toward sun and has longest day and shortest night September equinox Equator faces sun directly ; neierht pole tilts toward sun; all regions on earth have 12/12 December solstice Constant tilt of 23.5º Seasonal Variation in Sunlight Intensity September equinox AP Biology Minzenmayer

Global Air Circulation and Precipitation Patterns Descending dry air absorbs moisture Descending dry air absorbs moisture 30ºN 0º (equator) Ascending moist air releases moisture 30ºS 60ºS 23.5º 0º 30º 23.5º 30º Arid zone Tropics Arid zone

Great Ocean Conveyor Belt Labrador current Gulf stream Equator water Warm Cold water

bodies of water on climate Air cools at high elevation. 2 Cooler air sinks over water. 3 Warm air over land rises. 1 Cool air over water moves inland, replacing rising warm air over land. 4 Moderating effects of bodies of water on climate

Mountains Affect Rainfall Leeward side of mountain Wind direction range Ocean

Localized effects leeward windward desert 4/20/2018AP Biology Minzenmayer 2005-2006

Aquatic Biomes 4/20/2018AP Biology Minzenmayer 2005-2006

Aquatic Biomes Make up largest part of biosphere Water covers around 75% of Earth’s surface All with vertical stratification—forms unique ecological areas Photic Light for photoshythesis Aphotic Little to no light penetration Benthic Bottom areas; detritus rich Thermoclines Narrow layers of fast temperature change Separate warm upper layer and cold deeper layers AP Biology Minzenmayer

Zonation in Lakes What factors contribute to organism distribution? 4/20/2018AP Biology Minzenmayer 2005-2006

Freshwater Biomes Standing bodies of water--Lentic Lakes and wetlands Types of Lakes Oligotrophic Deep; nutrient poor; oxygen rich; sparse phytoplankton Eutrophic Shallow; higher nutrient content; lower oxygen; high phytoplankton concentration Moving bodies of water--Lotic Streams and rivers Estuaries Areas where freshwater streams or rivers merge with ocean AP Biology Minzenmayer

An oligotrophic lake in Grand Teton National Park, Wyoming A eutrophic lake in the Okavango Delta, Botswana

Seasonal Turnover of Lakes Thermal energy from sun warms surface waters Deeper waters remain cooler Semiannual Turnover Semiannual mixing of water in lakes Brings oxygenated water from surface to bottom Brings nutrient rich water from bottom to surface Winter Spring Summer Autumn 0º 4º 22º 4º 2º 4º 20º 4º 4º 4º 18º 4º 4º 4º 8º 4º 4º 4º 6º 5º 4º 4ºC 4ºC 4ºC 4ºC Thermocline

Okefenokee National Wetland Reserve in Georgia A headwater stream--Great Smoky Mountains An estuary in a low coastal plain of Georgia Mississippi River

Marine Zones 4/20/2018AP Biology Minzenmayer 2005-2006

Marine coral reef benthos intertidal 4/20/2018AP Biology Minzenmayer 2005-2006

Aquatic Biomes Lakes Coral reefs Rivers Oceanic pelagic and Fig. 52-15 Aquatic Biomes Lakes Coral reefs Rivers Oceanic pelagic and benthic zones Estuaries 30ºN Intertidal zones Tropic of Cancer Equator Tropic of Capricorn 30ºS

Terrestrial Biomes Tropical forest Savanna Desert Chaparral 30ºN Fig. 52-19 Terrestrial Biomes Tropical forest Savanna Desert Chaparral 30ºN Tropic of Cancer Temperate grassland Equator Temperate broadleaf forest Tropic of Capricorn Northern coniferous forest 30ºS Tundra High mountains Polar ice

Effects of Climate Desert Temperate grassland Tropical forest 30 broadleaf forest 15 Effects of Climate Annual mean temperature (ºC) Northern coniferous forest Arctic and alpine tundra –15 100 200 300 400 Annual mean precipitation (cm) 4/20/2018AP Biology Minzenmayer

Tropical Rainforest distribution: equatorial precipitation: very wet temperature: always warm characteristics: many plants & animals, thin soil 4/20/2018AP Biology Minzenmayer 2005-2006

Savanna distribution: equatorial precipitation: seasonal, dry season/wet season temperature: always warm characteristics: fire-adapted, drought tolerant plants; herbivores; fertile soil 4/20/2018AP Biology Minzenmayer 2005-2006

Desert distribution: 30°N & S latitude band precipitation: almost temperature: variable daily & seasonally, hot & cold characteristics: sparse vegetation & animals, cacti, succulents, drought tolerant, reptiles, insects, rodents, birds 4/20/2018AP Biology Minzenmayer 2005-2006

Chaparral distribution: coastal mid-latitude precipitation: seasonal, dry summer/rainy winter temperature: hot summer/cool winter characteristics: scrubby vegetation, drought-adapted, fireadapted, herbivores, amphibians, birds, insects 4/20/2018AP Biology Minzenmayer 2005-2006

Temperate Grassland distribution: mid-latitudes, mid-continents precipitation: seasonal, dry season/wet season temperature: cold winters/hot summers characteristics: prairie grasses, fire-adapted, drought tolerant plants; many herbivores; deep, fertile soil 4/20/2018AP Biology Minzenmayer 2005-2006

Temperate Deciduous Forest distribution: mid-latitude, northern hemisphere precipitation: adequate, summer rains, winter snow temperature: moderate warm summer/cool winter characteristics: many mammals, insects, birds, etc.; deciduous trees; fertile soils 4/20/2018AP Biology Minzenmayer 2005-2006

Coniferous Forest (Taiga) distribution: high-latitude, northern hemisphere precipitation: adequate to dry (temperate rain forest on coast) temperature: cool year round characteristics: conifers; diverse mammals, birds, insects, etc. 4/20/2018AP Biology Minzenmayer 2005-2006

Arctic Tundra distribution: arctic, high-latitude, northern hemisphere precipitation: dry temperature: cold year round characteristics: permafrost, lichens & mosses, migrating animals & resident herbivores 4/20/2018AP Biology Minzenmayer 2005-2006

Alpine Tundra distribution: high elevation at all latitudes precipitation: dry temperature: cold year round characteristics: permafrost, lichens, mosses, grasses; migrating animals & resident herbivores 4/20/2018AP Biology Minzenmayer 2005-2006