Ecology Biology 3500
                                                                                                                Dr. Adams
Review Sheet Number 1
(Test 1):
        Ecology Study of interactions between organisms and their environment.  Understand
that "environment" includes virtually EVERYTHING that the organism can interact with,
including individuals of their own species, all other organisms, and the physical environment
as well -- the air, water, soil, weather events, fire, temperature extremes, and even cataclysmic
events such as tidal waves, avalanches, volcanic eruptions (with all that comes with it: ash, lava,
and related effluvia), and, yes asteroid impacts.  Needless to say, these interactions are, in turn,
intimately tied into the evolution of the organisms, as all of these interactions are the natural
selective processes that shape the adaptations of the organisms through time.

Chapter 1:  What is Ecology?
    Overview:  can be studied on many levels -- individual, population, community, ecosystem,
and larger regional and even global interactions.

Some quick examples:
    1.  MacArthur -- resource partitioning by forest warblers; we will do a related lab later in the
            semester
    2.  Nadkarni -- plant nutrient resources in the tropical rain forest, including epiphytes and the mats
            they form in the canopy; host trees can tap into the mat with adventitious roots.
    3.  Davis -- plant community changes through time; the soil pollen record in sediment

NATURAL HISTORY and EVOLUTION UNIT

Chapter 2: Life on Land
    Biomes -- major divisions (large scale communities) of the (terrestrial) environment
        Major atmospheric determinants of biome (community) composition: 
            1.  Temperature -- heating by the sun; particularly important are the extremes
            2.  Moisture -- precipitation (and humidity/dew points)
            3.  Atmospheric Circulation (which is an important controller of temp. and precip.)
        To keep in mind:  geographic variation in temperature and precipitation is complex, and
            there is no single one item that controls temp and amount of precip on Earth's surface

        Make sure to read about climate diagrams (pgs. 15-17), and be able to interpret them.
Also understand, however, that a climate diagram represents average climate, and that
individual years can vary a lot, leading to moist years versus drought years (see pgs. 40-41).

    Soils -- complex mixtures of living and non-living material, typically with distinctive layering.
            This, of course, is another major determinant of biome composition
        Horizons:  O, A, B, C (and the underlying bedrock)
            Understand general characteristics of each.
            Horizons may be of differing depths, depending on many factors (precip and leaching,
                current biological activity, disturbance by man [tilling], etc.)

The Natural History of Biomes:  For each of the listed biomes, you should know basic
    characteristics.  These include: amount and timing (wet/dry seasonality) of precipitation,
    temperature driven seasonality (if apparent), location on the face of the planet, characteristics
    of the soils, and typical floral and faunal elements (and what major groups of organisms are
    lacking, such as reptiles/amphibians in subarctic/arctic)

Certain aspects to keep in mind as we go through:
    Epiphytes and epiphytic growth (why do some plants do this, which ecosystems have this
        type of growth and why), wet/dry seasons and occurrence of drought, parallel evolution of
        organisms with similar forms in similar habitats in different places in the world (eg., cacti
        and certain euphorbs in New World versus African deserts, respectively).

    Types of biomes: (this is not an exhaustive list, though all major biomes are listed here)
        The Tropics
            What distinguishes tropical biomes from temperate (or subarctic/arctic) types?
            Rain Forest, Dry Forest, Savanna (not listed are higher elevation biomes, which I
            WILL introduce you to and expect you to know something about)
        The Desert: 
           
Both tropical and temperate deserts (and arctic tundra is, in many respects, a desert)
        Temperate Biomes:
            Mediterranean (woodlands/shrub-, scrublands), Grassland, Forest (includes a
                variety of subsets: deciduous, mixed, and even rain)
        The Subarctic and Arctic:
            Boreal Forest (Taiga), Tundra

        Be aware that, in general, with higher latitude (tropics to the arctic) comes cooler temps.;
similar temperature gradients occur, with shifts in biome composition, with higher altitude.  We
will, for example, talk about alpine taiga and tundra (in essence, alpine islands)

    Islands:  though we typically think of a piece of land surrounded by water, mountaintops, in
essence, are islands "in the sky", and even ponds and lakes are actually islands for the aquatic
organisms that inhabit them.

Chapter 3: Life in Water
    The Hydrologic Cycle -- evaporation-precipitation; would happen without organisms.
        Organisms, in essence, temporarily but continuously insert themselves into the cycle.
        Turnover time:  amount of time for a particular reservoir (body) of water to be renewed.
            Rivers can be as fast as 2 weeks, and even the entire 1.3 billion km3 of water in the
                oceans is turned over in 3100 years.

    Aquatic Life Zones "Biomes" -- again, for each you should know basic characteristics:
        distribution on the planet, typical floral and faunal elements.
    Major influencing factors:  temperature (including extremes), salinity, light, oxygen, nutrient
        availability (Note: moisture/precipitation NOT in the list -- we are, after all, talking about
        aquatic ecosystems!!  Moisture only becomes important when the water is gone or almost
        gone, though the original source of the water is precipitation, and continuously supplies the
        water to the aquatic ecosystems to keep them in balance.)

 


    Types (not an exhaustive list):
        Marine ("Salt Water"):  currents play a major role in influencing temperature distribution
            Oceanic:  divided into several zones   
                Pelagic -- open waters (not including interactions with the ocean floor)
                         includes epipelagic, mesopelagic, bathypelagic, abyssal, hadal
                Benthic -- bottom habitat
                         deep ocean bottom:  thermal vent communities, w/ chemosynthesis in
                                bacteria as the producers for this community
            Neritic (continental shelf): from shore to about 200m deep
            Intertidal (littoral): the shoreline -- the epitome of the extreme ecotone
           
            Kelp & Coral -- in the neritic zone
                Kelp tend to be in temperate coastal waters; coral in tropical coastal water
                    Coral communities rival tropical rain forest in diversity (and productivity)

            The Intertidal: the most extreme ecotone
                low, high, spring, neap tides; forces driving tides -- sun, moon and local geography
                    Ranges from: supratidal fringe to subtidal zone; zonation of species obvious.
                    Height of tides and waves impact structure/diversity
                    Diversity influenced by rock (more diverse) or sand (less) diverse
                    Tide pools can experience significant extremes of temperature and salinity
                Estuaries:  where rivers meet the sea; extreme salinity changes, technically part of
                        the intertidal
                    Temperate salt marshes and tropical mangrove forests

   "Fresh" Water
      Rivers and Streams:
            Length/width, speed/direction of flow; varies depending on availability of ground-
                    water/precipitation/snow melt. 
                Maximum/mininum flow (active vs. wetted channels); flooding.
            Stratification -- riparian area; water column, benthic/hyporheic/phreatic zones
      Lakes:
            Littoral zone; Limnetic zone with epi-/meta-/hypolimnion; benthic zone

    Integrity (health) of aquatic systems:  assessment is done by species richness and using
        indicator species.