Humus data of the exploratory region in Italy (March 2012)

Usage Rights

This data is Free within projects.

Dataset Abstract

The humus form is the expression of the equilibrium between litter production, litter decomposition and humification in a forest ecosystem, resulting from the biological action of bacteria, fungi, and soil fauna. The observed humus form reflects a certain combination of ecological factors as climate, soil, tree species composition and management. In a site with constant climate and soil the effect of tree species composition on humus form becomes determining. The effect of tree species mixtures is less well understood and so far mainly studied in microcosm experiments. The idea is to quantify the mass of the ectorganic horizon and to describe the humus form. These features can be further related to variables as microbial activity, litter decomposition and earthworm biomass and diversity. All (30 x 30) m² plots are divided in nine (10 x 10) m² subplots. In every plot, an ectorganic sample (25 x 25 cm) and humus form classification is done in the middle subplot. The ectorganic sample is taken and humus form classification is done nearby (± 1m) the earthworm sampling location. Ectorganic samples are taken to the lab to get air-dried.

Dataset Design

For every plot of the focal region, plots (30 x 30) m2 are divided in nine (10 x 10) m2 subplots. In every plot, an ectorganic sample and humus form classification is done in the middle subplot. In principle, within every middle subplot, the sample is taken nearby the earthworm sampling location, but samples are not taken close to tree stems. On an estimated 30 by 30 cm square ground vegetation is removed in order that an ectorganic sample (25 x 25 cm) can be taken. Only the ectorganic forest floor material (OL, OF and OH, but not OLn and the mineral soil) is sampled in a bag. Later samples are transported to the lab where they can be air-dried in an oven to constant weight (75°C). Half a meter away from this sampling an observation trench (50 cm long and 20 cm deep) is dug in order to make the humus form description following the European Humus Form Reference Base (Zanella et al. 2011). Four places along the trench are observed in order to make a sound humus form identification. At least one photo of the humus profile per plot is made. The ectorganic sample is taken and humus form classification is done nearby (± 1m) the earthworm sampling location.

Spatial Extent

Italy

Temporal Extent

Spring 2012

Taxonomic Extent

Forest ectorganic horizon

Measurement Circumstances

Please use the Italian humus data cautiously. Identification of the Italian humus forms was not always that easy because of:
- disturbance of the top soil by wild boar in a lot of plots
- the human influence in the monocultures Castanea sativa in the recent past

Data columns available in the raw data part of this dataset

PlotID
Unique plot id
Data group: Exploratory plot id
Values
ITA05
ITA04
ITA03
ITA01
ITA02
Humus form
Humus form name, described according to the European humus forms reference base of Zanella et al. (2011)
Data group: Humus form
Keywords: process, decomposition
Values
Mesomull
Dysmoder
Eumoder
Hemimoder
Eumesoamphi