Weight and nutrient content of understorey vegetation in biomass subplots in May-June 2012 in the exploratory region in Italy

Usage Rights

This data is Free within projects.

FunDiv-intern

Dataset Abstract

Most of the plant diversity in European forests is found in the understorey, and despite its relatively low biomass compared to the forest overstorey, its functional importance is high (nectar source for pollinators, habitat for small mammals, affects tree regeneration, invasion resistance, decomposition and nutrient cycling (Gilliam 2007). Relationships between overstorey and understorey diversity and composition is tackled. For each of the plots per focal region, the core plot is divided in nine quadrants.For each of the plots per focal region, the core plot is divided in nine quadrants. In three quadrants (upper right, central, lower left), a vegetation subplot of 5 m x 5 m (as close as possible to the central quadrant; subplot in the central quadrant located in the upper half) is marked for identification and estimation of cover of understorey vascular plant species. Location of subplots exclude major heterogeneities at any scale of sampling (tree trunks, tracks and paths, streams and ponds, peaty pools, boulders and cliffs…). Thus, terricolous plants growing on mineral and organic soil of the undisturbed forest floor are represented. Within this subplot, understorey vegetation is identified (species, cover) and afterwards clipped in a zone of 0.5 m x 0.5 m (biomass subplot), where understorey vegetation is relatively abundant and where vegetation composition is representative for the whole subplot. Then, biomass is divided into 'woody' (woody juveniles, woody plants) and 'non-woody' (young seedlings, 'green' herbs). The biomass samples are dried for 24 to 48h at 70°C . Then they are weighed and analysed for P, C, N (Forest & Nature Lab, Ghent University).

Dataset Design

For each of the plots per focal region, the core plot is divided in nine quadrants. In three quadrants (upper right, central, lower left), a subplot of 5 m x 5 m (as close as possible to the central quadrant; subplot in the central quadrant located in the upper half) is marked for identification and estimation of cover of understorey vascular plant species (species, cover, maximum height, development stage). Within this subplot, understorey vegetation is identified (species, cover) and afterwards clipped in a zone of 0.5 m x 0.5 m, where understorey vegetation is relatively abundant and where vegetation composition is representative for the whole subplot. Then, biomass is divided into 'woody' (woody juveniles, woody plants) and 'non-woody' (young seedlings, 'green' herbs). Preparation of biomass samples for chemical analyses: dried at 70°C, grinded using a sieve of 1mm Before analyses of P-content, grinded biomass samples are 'destroyed' with HNO3/HClO4, diluted with demineralised water and filtered according to the method of Varian Instruments at work, AA-24 (McKenzie T., 1982. Automated multielement analysis of plant material by flame atomic absorption spectroscopy. Varian Instruments at work, AA-24). Analysis for P-content: destruction of biomass sample with the above mentioned method, then reaction of the destroyed biomass sample with metholsulphite, ammoniumheptamolybdate and sodiumacetate solution. Finally, measurement of the total P-content with a spectrophotometer type Varian Cary 50 at 700nm (Chemical analysis of plants and soils. Cottenie, Verloo,... Laboratory of analytical and agrochemistry, RUG). Analyses for C,N: analysis is done using an Elementar analyzer, type Vario Macro Cube in configuration CNS, with Argon as carrier gas. Catalytic combustion of the sample (1.5g) is carried out at a permanent temperature of up to 1200°C. This is followed by reduction of the combustion gasses on hot copper in the refuction tube. The formed gasses N2, CO2, H2O, SO2 are separated via purge and trep chromatography and afterwards detected on a thermal conductivity detector (TCD). A connected PC computes the element concentration from the detector signal, and the sample weight on the basis of stored calibration curves.

Spatial Extent

Italy

Temporal Extent

Spring 2012

Taxonomic Extent

understorey vegetation: woody and non-woody vascular species (herbs, seedlings) < 1.3m

Measurement Circumstances

Heavy rain on several days

Data columns available in the raw data part of this dataset

plot number
unique number ascribed to each plot
Data group: Exploratory plot id
Values
ITA03
ITA04
ITA02
ITA01
ITA05
subplot number
indicates which subplot within the plot is considered
Data group: Sub plot id
Values
10b
11b
11a
10a
10c
diversity
Number of target tree species present in subplot
Data group: Species richness
Keywords: diversity
Values
3
5
1
2
4
target Castanea sativa
Absence/presence of Castanea sativa in overstorey as target tree species
Data group: Presence data
Values
0
1
target Ostrya carpinifolia
Absence/presence of Ostrya carpinifolia in overstorey as target tree species
Data group: Presence data
Values
1
0
target Quercus cerris
Absence/presence of Quercus cerris in overstorey as target tree species
Data group: Presence data
Values
0
1
target Quercus illex
Absence/presence of Quercus illex in overstorey as target tree species
Data group: Presence data
Values
0
1
target Quercus petraea
Absence/presence of Quercus petraea in overstorey as target tree species
Data group: Presence data
Values
1
0
Weight non-woody
Weight of non-woody biomass present in biomass sample
Data group: Biomass
Keywords: process, understorey productivity
Values
0.008
0.014
0.01
0.013
0
P non-woody
P content of non-woody biomass present in biomass sample
Data group: Biomass nutrient concentration
Keywords: process, P
Values
1058.0858310626702
1047.019340159272
1004.7435897435898
1048.5077343039127
1087.664155005382
C non-woody
C content of non-woody biomass present in biomass sample
Data group: Biomass nutrient concentration
Keywords: process, C
Values
34.667
36.491
36.281
33.424
35.3
N non-woody
N content of non-woody biomass present in biomass sample
Data group: Biomass nutrient concentration
Keywords: process, N
Values
0.939
1.239
0.98
1.33
1.287
Weight woody
Weight of woody biomass present in biomass sample
Data group: Biomass
Keywords: process, understorey productivity
Values
0.02
0.036
0.015
0.019
0
P woody
P content of woody biomass present in biomass sample
Data group: Biomass nutrient concentration
Keywords: process, P
Values
125.0200267022697
1166.8391719745225
132.31900452488688
1019.1187739463601
1012.40317775571
C woody
C content of woody biomass present in biomass sample
Data group: Biomass nutrient concentration
Keywords: process, C
Values
43.579
43.306
43.915
44.208
43.559
N woody
N content of woody biomass present in biomass sample
Data group: Biomass nutrient concentration
Keywords: process, N
Values
0.547
0.488
0.386
0.508
0.414
Remarks
Remarks about plot/subplot
Data group: Helper
Values
chestnut canopy damaged by parasite attacks --> gap
disturbance by ungulates
disturbance by animals (wild boar) on the understorey
chestnut attacked by parasites, small canopy gap
chestnut crowns damaged (open canopy)