Dune

Kynes and his people turned their attention from these great relationships and focused now on micro-ecology. First, the climate: the sand surface often reached temperatures of 344° to 350° (absolute). A foot below ground it might be 55° cooler; a foot above ground, 25° cooler. Leaves or black shade could provide another 18° of cooling. Next, the nutrients: sand of Arrakis is mostly a product of worm digestion; dust (the truly omnipresent problem there) is produced by the constant surface creep, the "saltation" movement of sand. Coarse grains are found on the downwind sides of dunes. The windward side is packed smooth and hard. Old dunes are yellow (oxidized), young dunes are the color of the parent rock—usually gray.

Downwind sides of old dunes provided the first plantation areas. The Fremen aimed first for a cycle of poverty grass with peatlike hair cilia to intertwine, mat and fix the dunes by depriving the wind of its big weapon: movable grains.

Adaptive zones were laid out in the deep south far from Harkonnen watchers. The mutated poverty grasses were planted first along the downwind (slipface) of the chosen dunes that stood across the path of the prevailing westerlies. With the downwind face anchored, the windward face grew higher and higher and the grass was moved to keep pace. Giant sifs (long dunes with sinuous crest) of more than 1,500 meters height were produced this way.

When barrier dunes reached sufficient height, the windward faces were planted with tougher sword grasses. Each structure on a base about six times as thick as its height was anchored—"fixed."

Now, they came in with deeper plantings—ephemerals (chenopods, pigweeds, and amaranth to begin), then scotch broom, low lupine, vine eucalyptus (the type adapted for Caladan's northern reaches), dwarf tamarisk, shore pine—then the true desert growths: candelilla, saguaro, and bis-naga, the barrel cactus. Where it would grow, they introduced camel sage, onion grass, gobi feather grass, wild alfalfa, burrow bush, sand verbena, evening primrose, incense bush, smoke tree, creosote bush.

They turned then to the necessary animal life—burrowing creatures to open the soil and aerate it: kit fox, kangaroo mouse, desert hare, sand terrapin... and the predators to keep them in check: desert hawk, dwarf owl, eagle and desert owl; and insects to fill the niches these couldn't reach: scorpion, centipede, trapdoor spider, the biting wasp and the wormfly... and the desert bat to keep watch on these.

Now came the crucial test: date palms, cotton, melons, coffee, medicinals—more than 200 selected food plant types to test and adapt.

"The thing the ecologically illiterate don't realize about an ecosystem," Kynes said, "is that it's a system. A system! A system maintains a certain fluid stability that can be destroyed by a misstep in just one niche. A system has order, a flowing from point to point. If something dams that flow, order collapses. The untrained might miss that collapse until it was too late. That's why the highest function of ecology is the understanding of consequences."

Had they achieved a system?

Kynes and his people watched and waited. The Fremen now knew what he meant by an open-end prediction to five hundred years.

A report came up from the palmaries:

At the desert edge of the plantings, the sand plankton is being poisoned through interaction with the new forms of life. The reason: protein incompatibility. Poisonous water was forming there which the Arrakis life would not touch. A barren zone surrounded the plantings and even shai-hulud would not invade it.

Kynes went down to the palmaries himself—a twenty-thumper trip (in a palanquin like a wounded man or Reverend Mother because he never became a sandrider). He tested the barren zone (it stank to heaven) and came up with a bonus, a gift from Arrakis.

The addition of sulfur and fixed nitrogen converted the barren zone to a rich plant bed for terraform life. The plantings could be advanced at will!

"Does this change the timing?" the Fremen asked.

Kynes went back to his planetary formulae. Windtrap figures were fairly secure by then. He was generous with his allowances, knowing he couldn't draw neat lines around ecological problems. A certain amount of plant cover had to be set aside to hold dunes in place; a certain amount for foodstuffs (both human and animal); a certain amount to lock moisture in root systems and to feed water out into surrounding parched areas. They'd mapped the roving cold spots on the open bled by this time. These had to be figured into the formulae. Even shai-hulud had a place in the charts. He must never be destroyed, else spice wealth would end. But his inner digestive "factory," with its enormous concentrations of aldehydes and acids, was a giant source of oxygen. A medium worm (about 200 meters long) discharged into the atmosphere as much oxygen as ten square kilometers of green growing photosynthesis surface.