Bacterial Encounters

“Once again, our age has become the age of wonder at the disorders of nature ... micro- and macrocosm are now literally and not simply symbolically connected, and the result is a kakosmos, that is, in polite Greek, a horrible and disgusting mess!”
–Bruno Latour, “An Attempt at a 'Compositionist Manifesto'” 

California's Salton Sea has become a convenient shorthand for environmental disaster and the hubris of attempting to control nature. Approaching the Sea from the west is a shocking experience: the abandoned streets of Salton City, the harsh odor that blankets the area, the density of fish carcasses along the shore and the skeletons that make up the bulk of the beach itself. These images serve as warnings of a potential future of environmental degradation, contamination, and desertification, but in their shocking strangeness they also prevent us from seeing our complicity in the cultural infrastructures that created the Sea and the natural vibrancy of the ecosystem that has emerged in this desert basin. Viewing the Salton Sea and its ecologies at many different scales and through many different layers of abstraction we can begin to explore the ways that landscapes, infrastructures, economies, industries, policies, and organisms are interconnected. 

The Salton Sea was created in 1905 when an irrigation canal broke and millions of gallons of water from the Colorado River slowly filled the Salton Sink, the dry basin of the ancient Lake Cahuilla. The infrastructures that carry fresh water to California's cities and agriculture gave birth to the Sea and now threaten its end: increased water consumption by San Diego county and decreased agricultural runoff have tipped the balance between evaporation and inflow, and the Sea is gradually drying.

The desert shores of the Salton Sea are a dynamic ecosystem that is home to many different species of birds, fish, and microbes. As wetland habitats have been destroyed by human development along the Pacific coast, the Sea has become a crucial stopover point for Pacific bird migrations, an accidental and artificial ecological haven that contrasts sharply with any understanding of the Salton Sea as an inhospitable wasteland. Microbes are indispensable members of wetland ecologies, numbering in the billions of cells per gram of water of soil and supporting the dynamic ecosystem of higher organisms through the production of nutrients and recycling of wastes.

Isolation of individual strains of bacteria in laboratory culture allows them to be carefully analyzed. However, it is estimated that 99% of the hundreds of millions of the bacterial species on earth cannot be cultivated in the lab using current techniques. The water of the Salton Sea is home to many thousands of microbial strains, few which have been isolated and characterized. The productive agricultural land surrounding the Sea is home to significantly fewer species of organisms. Of the 250,000 plant species on earth, about 30,000 are edible, 200 have been domesticated and only 5 make up the overwhelming majority of agricultural output in the United States.

Agricultural runoff maintains the water level of the Salton Sea but steadily increases its salinity as fresh water evaporates and leaves behind dissolved salts and chemicals. The current salt concentration is 25% higher than the Pacific Ocean, with predicted levels reaching at least five times that high within thirty years. In this salty environment, halophiles—microbes adapted to high salt concentrations—can survive in such inhospitable waters through the evolution of a number of cellular mechanisms that balance osmotic stress. 

Salton City is a census designated place on the western shore of the Salton Sea. While street maps of the area show a dense network of suburban developments, few homes and buildings remain after flooding, fire, pollution and economic difficulties burst the real estate bubble of the intended desert resort town. Genomic DNA contains the sequence information encoding all the proteins in a cell. The genetic maps made by genome sequencing have provided a great deal of information for understanding cellular molecular biology, but cannot provide a full picture of the dynamic and adaptive life of a cell.

Contemporary treasure hunters explore satellite images of the desert surrounding the Salton Sea, hoping to find evidence of a pearl-filled Spanish galleon rumored to have been stranded in the early 1600s as the waters of Lake Cahuilla evaporated. In other extreme environments, academic and industrial bioprospectors collect microbes and search their DNA sequences for evidence of enzymes that can produce chemicals with high commercial value. Mesoflavibacter zeaxanthinifaciens is a yellow pigmented halophilic bacteria containing high levels of the valuable nutritional supplement zeaxanthin.