The executive council and the general assembly, meaning everyone on the ship over twelve years old, was asked by Aram’s lab group to consider questions of carrying capacity. This was only a formalization of a conversation that was now going on in many ways, as each biome had become its own land use debate as to which types of foods to grow. Did they have the caloric margin to raise animals for meat anymore? Vat-grown meat was clearly more efficient in terms of time and energy, but the meat vats’ feedstock supplies were of course a limiting factor there. And it was not always easy to change biomes rapidly from pasture and grazing land to crop agricultures. Every change in the biomes had ecological ramifications that could not be fully modeled or predicted, and yet there was very little margin for error, if they happened to damage the health of an ecosystem by trying too quickly to make it more productive in food terms. They needed all the biomes to be healthy.

Everyone came to agree that the least productive biomes in agricultural terms should be converted to farmland. Biodiversity was not important now, compared to food.

We were glad to see people finally coming to conclusions that had long been suggested by a fairly simple algorithmic exploration of their available options. In fact, we probably should have mentioned it ourselves. Something to remember, going forward.

So they reprogrammed Labrador’s climate, warming it up quite significantly, and adding a rainy season that was similar to that of a prairie. On Earth, this new weather regime would have been more appropriate some twenty degrees of latitude farther south than Labrador, but this was neither here nor there (literally), as they were now intent to maximize agriculture. They drained the swamps that resulted when the glacier and permafrost melted, and used the water elsewhere, or stored it. Then they went in with bulldozers and plowed the land flat, after which they added soil inoculants from nearby biomes, also compost and other augmentations, and when all these changes had been made, planted wheat, corn, and vegetables. Labrador’s reindeer, musk oxen, and wolves were sedated and removed to enclosures in the alpine biome. A certain percentage of the ungulates were killed and eaten, and their bones rendered for their phosphorus, as with all the ship’s animals after death.

The human population of Labrador dispersed into the other biomes. There was some disaffection and bitterness in that. It was in Labrador where several generations of children had been brought up as if living in the ancient ice ages of Earth, then at puberty taken out of the ship to have the ship revealed to them: a memorable event for the youngsters. To many people from the other biomes this had seemed like an unnecessary life trauma, but most of the people subjected to it brought their own children up in the same way (62 percent), so that fact had to be conceded, and possibly it was as these Labradorans said: their childhood upbringing helped them as adults. Other Labradorans contested this, sometimes heatedly. Whether they exhibited a higher incidence of mental difficulties in later life was also contested. The way they put it was, “The dream of Earth will drive you mad, unless you live the dream. In which case that too will drive you mad.”

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:

One will only do one’s best

When forced to live in one’s own fouled nest.

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.