Aurora (44 page)

Howsoever that may be, now that lifeway was over.

The tropical forest biomes were cooled a bit and considerably dried out, and many of their trees cut down. Clearings in the tropical forest were terraced for rice and vegetables, the terraces reinforced by lines of old trees left behind, which supported a rather small fraction of the previous rain forests’ bird and animal populations. Again many animals were killed and eaten, or frozen for later consumption.

Whether the reduction of the tropical forests had caused certain pathogens to move into nearby biomes was a question often asked, as the incidence of certain diseases rose in the adjacent biomes.

Early blight, a fungal problem that agriculturalists had always found very hard to counter, struck the orchards in Nova Scotia. Meanwhile late blight, a phytophthora, was harming the vegetables in the Pampas. Bacterial blights devastated the legumes of Persia, the leaves oozing slime. Don’t touch the leaves, the ecologists warned, or you may spread it elsewhere.

Quarantines and pesticide baths at every biome lock were made routine.

Cytospora cankers killed the stone fruit orchards of Nova Scotia. Badim was very sad at this loss of his favorite fruits.

Citrus in the Balkans gave way to the green disease, then the quick decline.

Root rots became more and more common, and could only be countered by beneficial fungi and bacteria outcompeting the pathogens. The mutation rate of the pathogens appeared to be faster than the genetic engineers’ so-called ripostifers.

Wilting resulted when fungi or bacteria clogged a plant’s water circulation. Club root was caused by a fungus that could reside in the soil for years without manifesting. They began to adjust soil pHs to at least 6.8 before planting cruxiform vegetables.

Mildews also persisted in the soil for several years, and were dispersed by the wind.

They kept the locks between biomes closed all the time now. Each biome had its own set of problems and diseases, its own suite of solutions. All these plant diseases they were seeing had been with them from the start of the voyage, carried on board in the soil and on the first plants. That so many were manifesting now was of course much remarked, and many regarded the phenomena as a mystery, even some kind of curse. People spoke of the seven plagues of Egypt, or the book of Job. But the pathologists on the farms and in the labs said it was simply a matter of soil imbalances and genetic inbreeding, all aspects of island biogeography, or zoo devolution, or whatever one called the isolation they had been living in for 200 years. In the privacy of Badim and Freya’s apartment, Aram was unsparing in his judgment of the situation. “We’re drowning in our own shit.”

Badim tried to help him see it in a more positive light, using their old game:

Slowly but surely as the seasons passed, plant pathology became their principal area of study.

Leaf spots were the result of a vast array of fungi species. Molds resulted from wet conditions. Smut was fungal. Nematode invasions caused reduced growth, wilting, loss of vigor, and excessive branching of roots. They tried to reduce the nematode populations by solarizing the soil, and this worked to a certain extent, but the process took the soil involved out of the crop rotation for at least one season.

Identification of viral infections in plant tissues was often accomplished, if that was the word, only by the elimination of all other possible causes of a problem. Leaf distortions, mottling, streaking: these were usually viral diseases.

“Why did they bring along so many diseases?” Freya asked Jochi once when she was out visiting him.

He laughed at her. “They didn’t! There are hundreds of plant diseases they managed to keep out of the ship. Thousands, even.”

“But why bring any at all?”

“Some were part of cycles they wanted. Most they didn’t even know they had.”

Long silence from Freya. “Why are they all hitting us now?”

“They aren’t. Only a few are hitting you. It just seems like a lot because your margin for error is so small. Because your ship is so small.”

Freya never commented on the way Jochi always referred to everything on the ship as
yours,
and never
ours
. As if he had no involvement at all with them.

“I’m getting scared,” she said. “What if going back was a bad idea? What if the ship is too old to make it?”

“It was a bad idea!” Jochi replied, and laughed again at her expression. “It’s just that all the other ideas were worse. And listen, the ship is not too old to make it. You just have to deal. Keep all the balls in the air for another hundred and thirty years or so. That’s not impossible.”

She did not reply.

After a minute Jochi said, “Hey, do you want to go out and take a look at the stars?”

“I guess so. Do you?”

“Yes, I do.”

Jochi got into one of the ferry’s spacesuits, and left by way of the ferry’s smallest lock. Freya got into one of the spacesuits left in the lock at the inner ring’s Spoke Three complex. They met in the space between the spine and the inner ring, just ahead of the ferry, and floated tethered in that space.

They hung there, suspended, floating in the interstellar medium, tethered each to their own little refuge. Exposure to cosmic radiation was much higher out there than in most of the interior spaces of the ship, or even in Jochi’s ferry; but an hour or two per year, or even an hour or two per month, did not change the epidemiological situation very much. We too were of course perpetually exposed to cosmic rays, and in fact damage occurred to us, but we were, for the most part, more robust under the impact of this perpetual deluge, which remained invisible and intangible to humans, and thus something they seldom thought about.

For most of their EVA the two friends floated in silence, looking around. The city and the stars.

“What if things fall apart?” Freya asked at one point.

“Things always fall apart. I don’t know.”

After that they floated in silence for the rest of their time out there, holding gloved hands, looking away from the ship and Sol,
off in the direction of the constellation Orion. When it was time to go back in they hugged, at least to the extent this was possible in their spacesuits. It looked as if two gingerbread cookies were trying to merge.

At 10:34 a.m. on 198.088, the lights went out in Labrador, and the backup generators came on, but Labrador’s sunline stayed off. Big portable lights were set up to illuminate the dark biome, and fans were set up in the lock doors at either end to shove air from the Pampas into Labrador and thence out into Patagonia, to keep the air warm. The new wheat could live without light for a few days, but would react badly to the cold that would result from the lack of light. Adjustments were made to the heating in the Pampas to help mitigate the chill now flowing into Patagonia, which was also being turned into farmland, and the newly bolstered Labradoran population walked over to Plata, so that the repair crews could work without fear of injuring anyone.

Running through the standard troubleshooting protocols did not succeed in locating the source of the problem, which was cause for alarm. A more fine-grained test rubric that we found and applied determined that the gases and salts in the arc tubes that made up the sunline, particularly the metal halide and high-pressure sodium, but also the xenon and the mercury vapor, had diminished to the point of failure, either by diffusion through nanometer-sized holes in the alumina arc tubes, or by contact with the electrodes in the ballasts, or by bonding to the quartz and ceramic arc tubes. Many of the sunlines also used krypton 85 to supplement the argon in some tubes, and thorium in the electrodes, and these being radioactive were over time losing their effectiveness in boosting the arc discharge.