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2 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Sylvia S. Mader Immagini e concetti della biologia

3 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 A12 - Living organisms and their environment

4 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Climate is designed by factors Climate is the average yearly temperature and precipitation of a region calculated over a long period. The Earth’s axis tilt is responsible for the alternation of seasons.

5 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Climate is designed by factors Earth’s rotation and revolution affect the global wind circulation and the global temperatures.

6 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Topography influences the climate The physical characteristics of a region influence the climate and the distribution of ecosystems. Elevation affects climate (temperature) as the latitude does.

7 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Topography influences the climate When mountains deviate the wind path, they affect precipitations. Wind circulation between sea and landmasses as monsoons influences the regional climate.

8 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Oceanic currents Winds, together with Earth’s rotation, cause a steady flow of water and redistribute global heat. Northern Hemisphere: currents move clockwise. Southern Hemisphere: currents move counterclockwise.

9 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Oceanic currents Gulf Stream transport warm tropical waters to the eastern coasts of North America and to the western coasts of Europe. Humboldt Current brings cold water northwards along Chilean Coast of South America. Here cold nutrient-rich water, rises in an upwelling process.

10 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 El Niño - Southern Oscillation El Niño is a phenomenon of alteration of normal water patterns off the Chilean Coasts. During El Niño - Southern Oscillation, the Humboldt Current is not cold and upwelling does not occur anymore.

11 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Biomes Terrestrial ecosystems are characterized by particular climates, mainly affected by the latitude.

12 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Major terrestrial ecosystems TUNDRA - Around North Pole Very cold (-12 °C to 6 °C) Little precipitation Permanent ice (permafrost) year-round within a meter of surface

13 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Major terrestrial ecosystems TAIGA (Coniferous Forest) - Below Arctic Circle Temperatures below freezing for half the year Moderate precipitation Long nights in winter and long days in summer

14 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Major terrestrial ecosystems TEMPERATE DECIDUOUS FOREST - Canada, Northern USA, Europe, Russia Hot summers and cold winters Ample precipitation

15 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Major terrestrial ecosystems GRASSLANDS - Russia, Mongolia, USA, South America Hot Summers and cold winters Moderate precipitation Good soil for agriculture

16 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Major terrestrial ecosystems SAVANNA - Africa, Australia, South America Warm temperatures (20-25 °C) Hot Summers Moderate precipitation Good soil for grazing

17 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Major terrestrial ecosystems DESERTS - Northern and Southern Hemisphere at 30° latitude Very Hot day (35-40 °C) and cold nights (7 °C) Low precipitation

18 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Major terrestrial ecosystems TROPICAL RAINFOREST - Equatorial regions of Asia, West Africa and South America Warm (25 °C) Heavy precipitation

19 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Aquatic ecosystems Fresh waters always end into seas and are divided by the flow velocity and slope into: 1.Streams 2.Rivers 3.Lakes 4.Deltas or estuaries

20 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Aquatic ecosystems Lakes are classified as oligotrophic, if they are nutrient-poor with low productivity, and eutrophic, if they are nutrient-rich with high productivity.

21 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Coastal ecosystems Estuaries Areas characterized by high fluctuations in salinity and high concentrations of nutrients.

22 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Coastal ecosystems Intertidal zones (or seashore) Area between tide marks. Organisms in the intertidal zone are adapted to an extremely changeable environment.

23 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Coastal ecosystems Marine waters are classified, considering the bathymetry and sunlight, into euphotic and pelagic.

24 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Coastal ecosystems Euphotic zone: exposed to sufficient sunlight for photosynthesis to occur. Is the portion of the ocean where most of the organisms both autotrophs (phytoplankton) and heterotrophs (zooplankton) live. The marine ecosystems with the highest biodiversity (as coral reefs) are located in the euphotic zone

25 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 Pelagic ecosystems Pelagic zone (open ocean) Not close to the bottom or near to the shore.