Island's composite features

" . . . we have a glimpse of ourselves and of our world islanded in its stream of stars."

Physical | Biological | Social

Island overview: parts of a barrier island are divided into zones.

Island Profile

Zones

Landscape features

Enchanted Isle maps and project.

Lagoon

Beach

Dune

Shrub Thickets

Over wash Fan

Marsh

Mangrove

Maritime Forest

Grass Flats

Oceans

Map

Transect

Zones

Restraints

on land use by percent of acreage needed for natural functions.

No place, even heavily urban areas can --nor should they-- be fully developed. Many urban locations have large areas of barren land, left vacant from poorly designed developments in the past.

Restraints

Restraints persist in any geographical area due to geological (soil), geomorphological (shape), topographical (surface contours), hydrological (moving water) and vegetational conditions (forests, grasslands, deserts) or the combined ecological constraints operating across boundaries.

Even heavily developed islands, such as Manhattan or peninsulas, such as San Francisco possess natural areas (open spaces) characterized by native and introduced vegetation. Central Park, the Brooklyn Botanical Gardens, or the Bronx Botanical Gardens in New York, or Golden Gate Park in San Francisco are examples of refuges for natural features, surface water and native vegetation to flourish beyond the pavement, structures and buildings of any urban setting. Urban spaces can of course be enhanced by natural and cultural additions to the features of any place.

landscape features	acres	percent
surface waters	3,629,440	5,671 miles
marshes	173,984	8.09%
floodplains	339,706	15.8 %
aquifers	181,792	8.3 %
aquifer recharge areas	118,896	6.0 %
prime agricultural land	248,816	11.7%
forests and woodlands	356,688	24 %
	1,419,882	73.89%

The extent of land use categories with respect to the urbanization of Philadelphia from the 1950s to the present.

Adapted from Ian McHarg's Design with Nature.

Physical | Biological | Social

The habitat approach to seashores

Physical

Barrier Islands migrate

Barrier Islands, created by longshore currents, are associated with the ocean margins of estuaries.

beach

Water movement and density of water masses in an estuary affect biological conditions because the mixing of water tends to trap essential nutrients.


<==== Down stream	Estuarine area	Up stream ====>

Biological

Creatures that require the shore to thrive are numerous and often define the character of the habitats to which they are confined, or regions in which they are found.

Beach	Piping Plover

The Fish and Wildlife Service writes that "Piping plovers return to their breeding grounds in late March or early April. Following establishment of nesting territories and courtship rituals, the pair forms a depression in the sand somewhere on the high beach close to the dunes. The nest is sometimes lined with small stones or fragments of shell."

Beach Profile

The zones are separate areas referred to as zonation within the Beach, shoreline areas. These beaches are called habitats by ecologists and naturalists to distinguish one area of the shoreline from another section.

Cape Hatteras, North Carolina.

Physical | Social | Map | Transect | Features

Types of vegetation


Krummholz effect: wind and salt from the ocean shape the tree.	Types of vegetation associations found in Florida

Succession as dunes move

beach

Clements and Cowles, when studying the Indiana dunes around Lake Michigan conceived of the shoreline in terms of a pioneer, or early stage species group establishing itself as the lake water receded and then each association of related plants succeeding the other, one after another.

Sequential stages in the recovery of bare ground.

succession

Forests edge Shrubs edge Grasses edge Forbs–pioneers edge

The tendency over time for diversity to increase if conditions are left relatively undisturbed.
Stages	common plants	#	duration
pioneer species:	railroad vine, ipomea,	1	seasons
Forbs,	dandelions, phlox, artemisia, rocket, a non-woody plant that is not a grass.	2	two-years
Grasses	marram, sea oats, salt grass, spartina	3	more years
Shrubs	coyote bush, ilex, berries, willows, alders, ceonothus	4	a decade
Forests	pines: loblolly, pond, sand, longleaf, limber	5	fifteen - twenty years
Secondary	oak, hickory, maple, birch, aspen,	6	fifty - sixty years
"Old growth"	cypress, cedar, redwoods, taxus,	7	century +