2.1- Soil Collection
We collected a total of six soil samples from three environmentally distinct locations: two samples from St Paul Island, Alaska, USA (StP.1: 57.136074, -170.82537; StP.2: 57.10577, -170.10563), and four samples from two sites in California, USA. The California samples include two from Fort Ord Natural Reserve in Marina (FO.1, an open sand dune: 36.68448, -121.77731; FO.2, a chaparral ecosystem: 36.68301, -121.78071), and two from and two from Younger Lagoon in Santa Cruz (YL.1, the basin of a coastal lagoon: 36.950081, -122.066756; YL.2, a grassland coastal terrace: 36.949314, -122.063575).
We designed and implemented field sampling protocols to minimize the risk of cross-contamination between soil samples. At each site, we wore clean gloves and used a clean trowel to collect soil from 2-6” below the surface, which we deposited into sterile 50mL falcon tubes. We sterilized trowels between sites serially with bleach and rinsed with ultraPure water and ethanol. Alaskan samples were kept cool during transfer to California and then frozen. Californian samples were frozen at -20˚C immediately after collection.