Figure 1. Notice the tear-drop shape of the 'tree islands,' and their orientation parallel to the direction of water flow.
        In the 1940's and 1950's, southern Florida was still very much uninhabited.  With the realization of the air conditioner, European Americans began to move to Florida in droves.  Rapidly, the lower east coast turned from a barrier ridge of sub-tropical forest and estuaries into a sprawling urban landcape.
        In order to accomodate the quicky growing population in southern Florida, provide them with freshwater, provide flood protection, and dry up that nasty old swamp, the
US Army Corps of Engineers dug hundreds of miles of canals and levees.  This successfully accomplished all three goals, and bifurcated and imperiled the Everglades in the process.  Luckily there are people such as the famous Marj. D. who's input changed the public perspective of the Everglades.  Don't get me wrong, the Everglades are not a nice place to live, or even to work.  It's hot, wet, squishy, smelly, and is full of sawgrass, which can deliver very nasty cuts.  There's not much to eat and there's little protection from the sun, or the mosquitos.  But it's still a pretty neat place to visit, and a beautiful thing to behold and  comprehend.
        Another blow to the natural Everglades ecology was that of the establishment of a massive agricultural zone in the northern-most Everglades, direclty south of Lake Okeechobee.  Not only does this agricultural zone consume everglades water, but it uses soluble chemical fertilizers which wash into the historically oligotrophic wetlands.  The excess phosphorous from the Everglades flows through out the wetland, changing ecological dynamics greatly, and allowing for invasive exotic plant species to take over the historical sawgrass ridges.
        I worked as a very very small part of the multibillion dollar ecological restoration project that continues to this day.
        Historically fresh water from Lake Okeechobee overspilled its banks and drained into the Everglades.  Being very very flat, the water flowed very very slowly southwards toward the sea and Florida Bay.  This water, which was essentially rain water, was oligotrophic--that is, very low in nutrients--especially phosphorous.  One of the most unique things about the Everglades is it's directional topography (Fig. 1).  The water, flowing at ~1 cm/sec, carried away accumulating detritus, thereby carving troughs, or sloughs (pronounced "slews") in the landscape.  Where there was already vegetation, or slower flow for any reason, detritus accumulated, allowing vegetation to grow.  Slowly, the landscape accumulated a stripped north south pattern of vegetated ridges and submerged sloughs.  This amazing pattern, likely took about 5,000 years to establish what we know as the original Everglades.

        Today, however, they are much different (Fig. 2).
Everglades Landscape Structure
             A
               |
           North
<---West     East---->
           South
               |
              V
Florida Bay----------->
Lake Okeechobee----------->
Agriculture
(US Sugar Industry)
Miami
Canal------->
Canal------->
Canal--->
Levee
    |
   V
Figure 2. View from space of the modern Remnant Everglades and various features.
Everglades National Park
Big Cypress Reserve
U.S. Army Corps of Engineers
Still not very ecologically savvy.
South Florida Water Management District
Mixing politics and science for 50 years.