The landscape architect’s unique strength and contribution to the com-prehensive planning process is a general knowledge of the natural sci-ences. Especially applicable are geology, hydrology, biology, botany, and ecology. These are in addition to such sciences as chemistry, physics, electronics, the humanities, and graphic communication. All are essen-tial to sound landscape design.
Geology
To understand the topographical base for any building project it is essential to know the structure and soil type of the earth’s surface layers.
The geologist learns early on that the tops of hills and ridges are gener-ally underlaid with the denser subsoil or rock—which make for solid footing. They make excavation more difficult and expensive, however.
This suggests the design of buildings without basements or lower levels.
Such costly excavated space is replaced where feasible with on-grade building units around courts, which also serve to block hilltop winds and hold the warming winter sun.
Sloping topography suggests terraced structures, open to the outward view and with low retaining walls. Except in regions of drought, lower ground and especially valley bottoms below vegetated uplands can be expected to have deeper, moister, richer soils for crops and gardens. Here basements or deeper foundations may be required to reach bearing, but the digging is easy.
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Volcano.
C. R. Tho nber, USGS, Hawaiian Volcano Observatory
Portion of geologic map, Ventura, California.
T. W. Dibblee, Geological Foundation
The level site, as on the plain, suggests an expanded building plan form, with wings to catch and check the breeze and courts to protect from the wind and drift. The study of geology also makes one extremely conscious of the deep-lying and shifting tectonic plates, the fault lines, volcanic cores, and the potential hazards of tornados and flooding. On a more modest scale it teaches of the various soil types and their qualities such as erosion resistance, fertility, and structural bearing. In land use planning, these are to be avoided for major transportation/transitways or settlements where lives are endangered. They are better reserved for welcome open space—left natural or with limited use, as for game lands or recreation. In storm-prone areas, early detection and monitoring techniques provide for early evacuation, saving thousands of lives and untold destruction.
All organisms turn energy and food into living matter while producing waste materials of various kinds. This waste matter becomes food for legions of saprophytes, literally “decay eaters.” These decomposers, which outnumber species of all other kinds, include beetles, fungi, nematodes, and bacteria. Through their complementary metabolic pathways, they return both essential nutrients and trace minerals to active circulation.
Sim Van der Ryn Stuart Cowan
The Human Habitat 11
The water cycle.
John M. Evans, USGS Colorado Water Science Center
Hydrology
Hydrology relates to land and resource planning in the form of water management. Those with an understanding of topography have learned to develop land use patterns in which extensive drainage inlets and deep sewer mains are not needed. Instead, surface drainage is conducted by swales to retention ponds or natural streams. Wastewater also flows by gravity in shallow laterals to outfall mains which follow the slope of the land. Water management has become increasingly important in regional planning since potable water shortage has become common. Irrigation and the transmission to urban centers have drained once-abundant rivers and watersheds. Population growth along both coasts has drawn down well fields to the point where saltwater intrusion is serious. This problem can no longer be overlooked. Nor can the large sweeps of lawn irrigated with freshwater be allowed. Irrigation of lawns and croplands will soon be treated by wastewater. With dual potable and treated waste-water systems, our freshwaste-water reserves can be replenished.
Biology
With biology being the study of all forms of life and their interaction, one would believe it to be central in all planning considerations. It is not. Usually, more attention is paid to appearances than to people. It is the biology-conscious designer or team member who tests each proposal against the experience of the users—who brings the project to life.
Botany
A first-year botanist has learned the value of vegetation. In the immense cloud of carbon dioxide or exhaust fumes that surround planet Earth it is only by the transpiration of vegetation that the essential oxygen of the fresh air we breathe is produced. Moreover, it is the earth’s vegetation that catches, transpires, and transmits to the aquifers the water on which all life depends. If that weren’t enough, it is from the worldwide store of vegeta-tion that we gather an astounding variety of foods, fibers, and timber. This knowledge should make conservationists of us all. It may in time. Mean-while, in most unmindful construction a first thought is to clear the land.
In comprehensive land planning the botanist will be quick to point out the areas of natural cover that should be preserved. Costly clearing and
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Botanical specimen.
Belt Collins
ground cover replacement will thus be precluded. In the landscape plan-ning process a botany doctorate is not needed, except in special cases. It is enough to know the local plants, their characteristics, and the condi-tions of growth under which they thrive. When existing plants are left undisturbed they need little care. Exotic ornamentals, needing more attention, are to be used sparingly.
Ecology
Ecology is a relatively new science concerned with the relationship of liv-ing thliv-ings and their environment. It has much to tell us in the plannliv-ing of favorable growth and land use patterns and the elimination of urban sprawl.
Other
A generalized knowledge of the natural sciences is the mark of a well-schooled landscape architect. No other profession is trained in this vital aspect of comprehensive land use planning.