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The Biosphere Xxx… False-color composite image of global photoautotroph abundance from Wikimedia Commons Terrestrial Biomes Large-scale biological communities sharing similar plant growth forms - convergent adaptations to similar physical environments Cain, Bowman & Hacker (2014), Fig. 3A Terrestrial Biomes Xxx… Cain, Bowman & Hacker (2014), Fig. 3.5 Terrestrial Zoogeographic Regions Published as “an update of Wallace’s zoogeographic regions” Map from Holt et al. (2013) Science Biomes & Biogeographic Realms World Wildlife Fund team identified 14 terrestrial biomes Map from Olson et al. (2001) Bioscience Ecoregions … and 867 distinct ecoregions Map from Olson et al. (2001) Bioscience Tropical Rainforests Walter & Lieth (1967) Climate Diagram (Scales 1 C to 2 mm precip.) Cain, Bowman & Hacker (2014), Fig. 3A Tropical Rainforests Dominant plants = broad-leaved evergreen trees Also epiphytes, lianas, palms, and generally sparse understory More-or-less continuous growing season Contain ~50% of Earth’s species in ~11% of terrestrial veg. cover Cain, Bowman & Hacker (2014), Fig. 3A Tropical Rainforests E.g., scatter-hoarding of seeds by rodents Photo of agouti and Astrocaryum palm fruits by Christian Ziegler; Figure from Jansen et al. (2012) PNAS Tropical Seasonal Forests & Savannas Yellow region = Insufficient precip. for plant growth Cain, Bowman & Hacker (2014), Fig. 3B Tropical Seasonal Forests & Savannas Tropical dry forests Thorn woodlands Tropical savannas Resource availability, fire & large herbivores help determine the balance between grasses vs. woody species Pronounced wet / dry seasons Cain, Bowman & Hacker (2014), Fig. 3B Tropical Seasonal Forests & Savannas E.g., protection of plants against herbivores by ants Photo of Pseudomyrmex on Vachellia (formerly Acacia) – Wikimedia Commons; Table – Janzen (1966) Evolution Hot Deserts Sparse populations of plants & animals Succulent plants are common Sustained periods of high temp. & low water avail. Cain, Bowman & Hacker (2014), Fig. 3C Hot Deserts E.g., large-male advantage in lek-mating tarantula hawks Photo of Tarantula Hawk and Tarantula – http://blogs.sandiegozoo.org/tag/tarantula-hawk; Figure from Alcock (1981) Behavioral Ecology & Sociobiology Temperate Grasslands Blue region = Temp. below freezing Cain, Bowman & Hacker (2014), Fig. 3D Temperate Grasslands Dominant plants = grasses Warm, moist summers & cold, dry winters Some have sufficient rainfall to support woody veg., but fire & grazers maintain grasslands Soils rich in organic matter Cain, Bowman & Hacker (2014), Fig. 3D Temperate Grasslands Large ungulate & marsupial (in Australia) grazers are common Photos of pronghorn antelope and red kangaroo from Wikimedia Commons Temperate Shrublands & Woodlands Winter rainy season (e.g., Mediterranean-type climates) Fire is a common feature Sclerophyllous leaves are common Cain, Bowman & Hacker (2014), Fig. 3E Temperate Shrublands & Woodlands Resprouting is common Photo from http://www.eco.science.ru.nl/plantecology/Estrela/pig_fireecology.html Temperate Deciduous Forests Deciduous leaves owing to freezing temperatures Sufficient rainfall & soil fertility to support tree growth Cain, Bowman & Hacker (2014), Fig. 3F Temperate Deciduous Forests Insect populations sometimes outbreak Photo of tent caterpillars from http://www.twincities.com/outdoors/ci_25948887/minnesota-tent-caterpillaroutbreak-concerns-eased-by-dnr Temperate Evergreen Forests From warm coastal zones to cool maritime climates Generally on nutrient-poor soils Northern Hemisphere – needleleaved conifers Southern Hemisphere - needleleaved & broad-leaved Cain, Bowman & Hacker (2014), Fig. 3G Temperate Evergreen Forests Photo of British Columbian rainforest from Wikimedia Commons; K. Harms photo of Florida pine savanna Boreal Forests / Taiga Coniferous species Extreme weather Permafrost common Cain, Bowman & Hacker (2014), Fig. 3H Boreal Forests Immense carbon pools Photo of Canadian taiga from Wikimedia Commons Tundra Beyond treeline Dominated by sedges, grasses, forbs & prostrate shrubs Primarily in the Arctic Extreme weather Permafrost common Cain, Bowman & Hacker (2014), Fig. 3I Tundra Prey are relatively predictably seasonally abundant during a short growing season Photo from http://www.reddit.com/r/itookapicture/comments/1nh6eo/itap_of_a_few_mosquitoes_in_alaska/ Ecotones Transition zones between biomes or ecosystems Photo of lakeside ecotone from Wikimedia Commons Where the Land Meets the Sea Estuary – junction of a river & ocean Mangrove – shallow estuaries & mudflats with salt-tolerant evergreen woody species Salt Marsh – found on sediments carried to shorelines by rivers Photos of Amazon estuary, a mangrove & a salt marsh from Wikimedia Commons Where the Land Meets the Sea Beaches / Sandy Shores – unstable substrate limits opportunities for plants, so limited opportunities for animals Rocky Intertidal – stable substrate alternates between terrestrial & marine Etc. Photos of a Galapagos sandy / boulder beach & a rocky intertidal shoreline from Wikimedia Commons Marine Biomes Coral Reef – warm, shallow water Kelp bed – large brown algae in clear, shallow, temperate oceans Photos of coral reef, kelp bed & seagrass bed from Wikimedia Commons Seagrass bed – flowering plants on subtidal mud or fine sand Marine Biomes Deep sea – extreme pressure & temperature; no light, so limited, patchy energy supply Etc. Photo of 1700 m deep gray whale fall from Wikimedia Commons; photo of octopus that broods eggs for 4 yr at ~1700 m deep from http://www.newsweek.com/octopus-broods-eggs-record-412-years-then-dies-scientists-report-262157 Anthropogenic Influence on Planet Earth We live in a very different world from the one we inherited from our Pleistocene forebears Photo (1929) of New York City (previously Temperate Deciduous Forest) from Wikimedia Commons Anthropogenic Influence on Planet Earth “Perhaps it’s my natural pessimism, but it seems that an awfully large part of travel these days is to see things while you still can.” Quote from Bryson (2001, pg. 279) In a Sunburned Country; photo of polar bear from Wikimedia Commons