This dataset includes measurements of soil respiration in 20 plots (250 x 10 m each) in the Brazilian Amazon. Study plots were distributed across a gradient of forest disturbance, including: undisturbed primary forests , logged primary forests, logged-and-burned primary forests, and secondary forests. Data were collected from October 2014 until May 2018. In December 2015, during the El Niño-mediated drought, eight of our study plots were affected by understory fires.
Publication date: 2019-01-31
This dataset is part of the following
We assessed roots production in 20 study plots (0.25ha) distributed along a gradient of forest disturbance in Eastern Amazonia: undisturbed primary forests (n = 5), logged primary forests (n = 5), logged-and-burned primary forests (n = 5), and secondary forests (n = 5). Forest disturbance classes were based on both an analysis of canopy disturbance in a chronosequence of satellite images (1988 to 2010) and on field assessments of fire scars, charcoal, and logging debris.
In each plot we installed four in-growth soil cores (12 cm Diameter x 40 cm deep) using a plastic mesh (mesh size = 1.5cm). Each in-growth core was placed 50m apart. Cores were set 30cm deep into the soil, with 10cm aboveground. Before each sampling, both the soil temperature were measured inside and outside the in-growth core. In the field, each soil core was placed on a plastic sheet and broken in smaller parts until was homogenically spread. For the first measurement, called root stock, roots were collected in 24 intervals of five minutes each (three minutes break between intervals). The soil was homogenized before every new interval. After the sampling, the soil was placed back in the hole with the in-growth core inside. The sampled roots were taken to the laboratory and washed in a plastic sieve (2 mm mesh size), oven-dried at 60oC for 72 h and weighed. The second measure is taken 3 months after the first one, which gives us the first stock of fine root production. We collect the soil in the same hole and use the same method to collect the roots, but with 12 intervals of five minutes each (three minutes break between intervals). The laboratory procedure was the same. After three months, we take another measure in the same hole, using the same method as the second measure. After one year, the soil core is taken around 30 cm next to the first one, as the soil becomes physically disturbed and compact, which influences root production. For this new in-growth core, we start the sampling again with 24 intervals.