2.3 Biomass sampling and analysis
A total of 10 sampling points was randomly selected at the waste dump
and an area of 1 m2 at each point was marked for
vegetation sampling. We used the harvest method to estimate shoot and
root biomass. Soil particles attached to roots were separated by soaking
and washing with a fine jet of water with ultrasonicator. During soil
sampling, rooting depth was measured (i.e., depth of root penetration).
Shoot and root biomass was separated and oven-dried at
65oC for 48 hours to measure the weight of the dry
biomass. Biomass samples were finely grounded and a sieved
(<1mm) to determine the total carbon (C) and nitrogen (N)
using an elemental analyzer (Euro EA 3000 Eurovactor, Italy). Dry mulch
accumulated on the surface layer was collected by using quadrate (size:
30 cm × 30 cm), from the same location where soil and vegetation samples
were collected.