1. Environment and Abundance; Biomes

2. Conditions An abiotic factor that influences the immediate survival of an organism – temperature, humidity, pH, salinity, wind velocity, current flow, soil, pollutants, etc.

3. Law of the Minimum The distribution of a species will be controlled by that environmental factor for which the organism has the narrowest range of adaptability or control. - Carl Sprengel 1828

4. Liebig’s Law of the Minimum - 1840 Or – the nutrient in lowest supply will set the limit to plant growth

5. Range of Tolerance Limits

6. Distribution Is there a relationship between geographic range (distribution) and population size?

7. Tetraphis pellucida

9. Rule of thumb: The range of the average species corresponds to the range of the average graduate student. University of Connecticut Ecology Grad Students

11. south north

12. Range size and abundance Ecologists have long suspected that a species that is widespread in its distribution may tend to be more common or abundant in its population size What causes such patterns? 1. sampling error 2. ecological specialization 3. local population model

13. Sampling Errors – Rare Species Knotroot bristlegrass and peregrine falcon

14. Ecological specialization - generalists

15. Local population model - dispersal

16. Climate and distribution Climate, particularly temperature and precipitation, influences the distribution of the earth's terrestrial organisms In each major kind of climate, a distinctive type of vegetation develops - for desert plants occur in arid (dry) climates, grasses with semi-arid climates and forests with moist climates Certain animals, fungi and other organisms are associated with particular vegetation types

17. Biomes A Biome is a large, relatively distinct terrestrial ecosystem characterized by particular climate, soil, plants and animals, regardless of where it occurs on earth A biome's boundaries are determined by climate more than by any other factor

18. Biomes

19. Limits to Biome Distribution

21. Tundra

22. Tundra occurs in extreme northern latitudes where the snow melts seasonally (southern hemisphere has no equivalent) Tundra has long, harsh winters and very short summers - growing season is 50 to 160 days depending on location – summer days are long Tundra soils are young - formed after last ice age, nutrient poor, little organic matter - have permafrost - permanently frozen layer of soil Plants mostly less than 30 cm tall – mosses, lichens, sedges, grasses Animals – weasels, foxes, snowshoe hares, ptarmigan, caribou, mosquitoes, blackflies

23. Taiga

24. Taiga - evergreen forests of the north Taiga is found in northern America, Asia and Europe - covers 11% of land Winters cold and severe - growing season longer than tundra - greater than 160 days - little precipitation, about 50 cm (20 inches) per year Soil is acidic, mineral-poor, deep layer of poorly decomposed pine and spruce needles at surface Numerous lakes and ponds Plants – aspen, birch, but spruce and fir dominate Animals – caribou, wolves, bears, moose, rodents, rabbits, lynx, sable, many migratory birds, many insects

25. Temperate rain forests

26. Occurs on northwest coast of North America, southwestern Australia, southern South America, nothern Japan very high precipitation - 200 to 380 cm (80 to 152 inches), much condensation from coastal fogs - little seasonal temperature variation - winters mild and summers cool Nutrient poor soil, but may have high organic content Plants – evergreen trees – western hemlock, Douglas-fir, Sitka spruce, western red cedar, many epiphytes – mosses, lichens, ferns Animals – squirrels, deer and numerous birds

27. Temperate deciduous forests

28. Occur where temperate zone precipitation ranges from 75 to 125 cm (30 to 50 inches) Typically have hot summers and cold winters soil has rich topsoil with much organic matter, deep clay-rich lower layer In US dominant plants are broad-leaved trees – oaks, hickory, beech maple – in south broad- leaved evergreens – live oak, magnolia Animals – deer, bear, wolves, cougars, rodents, many birds, many reptiles and amphibians

29. Temperate grasslands

30. Occur where annual precipitation is 25 to 75 cm (10 to 30 inches) Summers hot, winters cold, rainfall is often sporadic soil is rich in organic matter, minerals build up in top layer of soil, dead organic matter from annual die-back of grasses builds up soil organics, grass roots may form turf or sod shortgrass prairies may be called steppes, more rainfall than deserts but not much - 10 to 15 inches Plants – grasses dominate – tallgrasses where wetter, shortgrasses where drier – trees only along rivers Animals – bison, antelope, wolves, coyotes, prairie dogs, ferrets, birds of prey, grouse, reptiles, many insects

31. Mediterranean ecosystems

32. Mediterranean - thickets of evergreen shrubs and small trees some temperate areas have climates with mild winters with abundant rainfall and very dry summers - called Mediterranean climates - occur around Mediterranean, California, western Australia, Chile, South Africa In California we call this ecosystem chaparral - soil is very thin and nutrient poor Fires are common, frequent in late summer, early autumn plants usually dense growth of evergreen shrubs, but may have short scrubby pines and oaks - often have sclerophyllous leaves - hard, small, leathery leaves that resist water loss Animals – mule deer, wood rats, chipmunks, lizards, many songbirds, other birds

33. Deserts

34. Deserts are very dry habitats of both temperate and tropical zones - low water content of the desert atmosphere leads to wide daily temperature range deserts vary greatly depending upon amount of precipitation - usually less than 25 cm (10 inches) per year desert soil poor in organics, rich in minerals some deserts so dry have virtually no plant life - Namib and Atacama desert Plant cover sparse, much soil exposed – perennial and annual or ephemeral plants – in North America – cacti, yucca, Joshua trees, bunchgrass Animals – small – rodents, lizards, tortoises, snakes, birds, insects

35. Tropical savanna

36. Savannas are a tropical grassland which typically have widely scattered trees either low rainfall or seasonal rainfall with prolonged dry periods - often 85 to 150 cm (34 to 60 inches) Temperature doesn't change much - often in 80's or 90's Savanna soil is low in mineral nutrients Tropical savanna found in Africa, South America and northern Australia Plants – grasses, acacia trees – adapted to survive or recover quickly from fire Animals – huge herds of hoofed mammals in Africa – many predators – lion, leopard, hyena, wild dog

37. Tropical rainforest

38. Tropical rain forest occurs where temperatures are high throughout the year and precipitation occurs almost daily - annual precipitation may be 200 to 450 cm (80 to 180 inches) - much of the rainfall is locally recycled as water that enters atmosphere from transpiration quickly falls out again Soil is usually very old and nutrient poor, low in minerals and organics - decomposition and recycling is very quick due to high temperature and high availability of water extremely diverse forests - trees, lianas – evergreen flowering trees Animals – very diverse insects, reptiles, amphibians, birds, monkeys, sloths

39. Distribution of Biomes in Current Climate

40. Possible Distribution of Biomes in Climate with CO2 Doubled

41. Global Climate Change

42. Potential climate migration for Illinois

44. Will my prairie ecosystem change from this to this? Illinois tallgrass prairieEast Texas Piney Woods

45. Or something entirely different? Dan Janzen has predicted that with increasingly human dominated ecosystems, global climate change and the spread of cosmopolitan non- native species, the entire world will become ecologically uniform.