Figure 1. Distribution of sampling sites of annual ephemerals in the
desert of northern Xinjiang, China
In the quadrat, we selected 10 plants whose plant height and root collar
diameter are similar to the standard plants, and used big shovel, small
shovel, 30cm steel ruler, brush and other tools to dig all plant roots
in situ with ”trench method”(Shan et al., 2012). That is, a volume of
10cm × 5cm × 40cm trench at a distance of 3-4 cm from the individual
plant was dug with big shovel. Then, the soil around the root was
cleared into the trench with small shovel. When the larger diameter
taproot was exposed, in order to avoid root system damage, we used a
steel ruler to continue to clean the soil around the finer root
branches. After the root system of plant was completely exposed, the
maximum root depth (MRD) of them were measured in situ with a tape
measure and recorded it. After that, carefully placed the plant
individuals in a plastic bag, and then transported them to store in an
ice box back to the laboratory.