Biodiversity Data Journal :
Data Paper (Biosciences)
|
Corresponding author: Valeria Guzmán-Jacob (valerova@hotmail.com)
Academic editor: Emmanuele Farris
Received: 22 Jul 2021 | Accepted: 11 Sep 2021 | Published: 07 Oct 2021
© 2021 Valeria Guzmán-Jacob, Patrick Weigelt, Dylan Craven, Gerhard Zotz, Thorsten Krömer, Holger Kreft
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Guzmán-Jacob V, Weigelt P, Craven D, Zotz G, Krömer T, Kreft H (2021) Biovera-Epi: A new database on species diversity, community composition and leaf functional traits of vascular epiphytes along gradients of elevation and forest-use intensity in Mexico. Biodiversity Data Journal 9: e71974. https://doi.org/10.3897/BDJ.9.e71974
|
|
This data paper describes a new, comprehensive database (BIOVERA-Epi) on species distributions and leaf functional traits of vascular epiphytes, a poorly studied plant group, along gradients of elevation and forest-use intensity in the central part of Veracruz State, Mexico. The distribution data include frequencies of 271 vascular epiphyte species belonging to 92 genera and 23 families across 120 20 m × 20 m forest plots at eight study sites along an elevational gradient from sea level to 3500 m a.s.l. In addition, BIOVERA-Epi provides information on 1595 measurements of nine morphological and chemical leaf traits from 474 individuals and 102 species. For morphological leaf traits, we provide data on each sampled leaf. For chemical leaf traits, we provide data at the species level per site and land-use type. We also provide complementary information for each of the sampled plots and host trees. BIOVERA-Epi contributes to an emerging body of synthetic epiphytes studies combining functional traits and community composition.
BIOVERA-Epi includes data on species frequency and leaf traits from 120 forest plots distributed along an elevational gradient, including six different forest types and three levels of forest-use intensity. It will expand the breadth of studies on epiphyte diversity, conservation and functional plant ecology in the Neotropics and will contribute to future synthetic studies on the ecology and diversity of tropical epiphyte assemblages.
elevational gradient, vascular epiphytes, functional traits, forest-use intensity, carbon isotope ratio, nitrogen isotope ratio.
Elevational gradients provide a wide range of opportunities for studying the effects of different ecological and evolutionary factors on biodiversity patterns. Steep elevational gradients in temperature, precipitation and other climatic variables usually play a fundamental role in shaping plant diversity (
Functional traits are measurable characteristics of individual plants impacting their growth, reproduction and survival (
Mexico is a country with high floristic diversity and endemism. Almost 50% of its 23,114 native species of vascular plants are endemic. However, Mexico has lost approximately half of its forest cover in the past 50 years (
Design of a 20 × 20 m plot for sampling vascular epiphytes. The four subplots are indicated by dashed blue lines. The central tree shows the five Johansson zones indicated with red lines, base of the trunk (JZ 1), lower trunk (JZ 2a), upper trunk (JZ 2b), inner canopy (JZ 3), mid-canopy (JZ 4) and outer canopy (JZ 5). We used the adapted version of the system, where the trunk is divided into two separate zones (
Total species number per elevation and forest-use intensity. Number of species of vascular epiphytes recorded at the different levels of forest-use intensity (FUI: OG; old-growth forest, DF; degraded forest and SF; secondary forest) at each of the study sites (0 m, 500 m, 1000 m, 1500 m, 2000 m, 2500 m, 3000 m and 3500 m). At each elevational site, five plots were sampled per FUI. Red points indicate the total number of species per study site.
Even when epiphytes represent about 9% of all vascular plant species (
BIOVERA-Epi includes plot data from an elevational gradient located in the central part of the State of Veracruz, Mexico. Specifically, it contains two distinct, but related datasets: the first dataset includes distribution and plot level frequency information (frequency.subplot) for 271 vascular epiphyte species, sampled in 120 20 m × 20 m plots along the elevational gradient, ranging from 0 to 3500 m a.s.l. The second dataset includes measurements of nine morphological and chemical leaf traits for 102 species, 474 individuals and a total of 1595 leaves, which were sampled in 45 plots at three sites along the same elevational gradient. The leaf traits studied were: leaf area, leaf density, specific leaf area (SLA), leaf dry matter content (LDMC), leaf nitrogen content, leaf phosphorus content, leaf carbon content, nitrogen isotope ratio (d15N) and carbon isotope ratio (d13C). For each plot, we also provide geographical coordinates, forest-use intensity (old-growth, degraded, secondary) and elevation. For the surveyed host trees, we report diameter at breast height (DBH), total height (H) and species identity (see Data collection).
Conclusion: The species distribution dataset shows the value of old-growth forest for epiphyte diversity, but also show that degraded and secondary forest, depending on the elevation, may maintain a high species diversity and thus play an important role in conservation planning. Across our 120 study plots, Orchidaceae was the family with more species within the Angiosperms and Polypodiaceae within the Pteridophytes (Fig.
Sampling design
The elevational gradient spanned from sea level to 3500 m on the eastern slopes of Cofre de Perote, a 4282 m extinct volcano located in the central part of Veracruz State, Mexico (Fig.
We investigated three levels of forest-use intensity (FUI) that could be consistently found along the entire gradient (following
Data collection: species distribution
We selected eight study sites, each separated by ca. 500 m in altitude along the elevational gradient, representing the following elevational ranges: 0-45 m, 610-675 m, 980-1050 m, 1470-1700 m, 2020-2200 m, 2470-2600 m, 3070-3160 m and 3480-3545 m. At each study site, we surveyed vascular epiphytes in five non-permanent 20 m × 20 m plots for each of the three FUI levels, respectively, yielding a total of 120 plots (Suppl. material 1). We used a Garmin® GPSMAP 60Cx device (Garmin International, Inc. Kansas, USA) to record geographical coordinates and elevation for all plots. Vascular epiphytes were surveyed between July 2014 and May 2015 following the sampling protocol of
Data collection leaf trait dataset
In a separate sampling campaign from June to September 2016, leaf trait sampling took place at three of our studied elevational sites (0, 500 and 1500 m a.s.l.). In this field campaign, we aimed to resample as many vascular epiphyte species from the first survey as possible. At each elevation, epiphytes were sampled up to a height of 20 m on one or more trees using the single-rope climbing technique. Epiphytes below 6 m were sampled from the ground using a collecting pole. Functional traits were collected for all vascular epiphyte species classified as holoepiphytes (epiphytes in the strict sense, i.e. living their whole life cycle as epiphytes). In this dataset, we excluded nomadic vines because of their contact with the ground (
Leaf trait measurements
We collected between one and three leaves per adult individual from three individuals to obtain, if possible, a maximum of 10 leaves per species. We sampled fully expanded leaves without visible signs of herbivory or disease. Collected leaves were rehydrated in a sealed plastic bag and kept cool in a refrigerator at 7°C for a minimum of 8 hours before taking measurements. Leaf area was measured with a portable laser area meter (CI-202, CID Bio Science Inc. U.S.A.). Leaf thickness was measured with an electronic calliper (precision: 0.05 mm). Leaves were weighed to obtain fresh weight (balance: A and D GR-202; A and D Company, Tokyo, Japan; precision: 0.1 mg), then oven-dried at 70°C for 48 h or until obtaining a constant dry weight and reweighed to obtain dry weight. For each leaf, we determined the following morphological traits following
d13C (‰) = [(13C/12C sample)/ (13C/12C standard)-1] × 1000
d15N (‰) = [(15N/14N sample)/ (15N/14N standard)-1] × 1000
To determine leaf phosphorus, 5 mg of the sample were digested in 200 μl concentrated nitric acid (HNO3) and 30 μl 30% hydrogen peroxide (H2O2) (
Species identification
Vouchers from the first field campaign were collected, if possible, in triplicate for preservation as herbarium specimens. These specimens were identified using relevant literature (
Data were collected at eight different sites distributed across an elevational gradient along the eastern slopes of Cofre de Perote mountain, Veracruz State, Mexico.
19.51 Latitude and -96.15 Longitude Latitude; -96.38 Longitude and 19.59 Latitude Longitude.
1) Epiphytes: The species distribution dataset covers 271 epiphyte species belonging to 92 genera and 23 families. The most species-rich families are Orchidaceae (82 species), Polypodiaceae (50), Bromeliaceae (41), Piperaceae (20), Cactaceae (14) and Araceae (12). A total of 72.2% of the sampled epiphyte individuals could be identified to species level, while another 26.1% were identified to genus level and 1.7% to family level. The trait dataset includes measurements for 1595 leaves from 474 individuals belonging to 102 species in 10 families. In total, most species were orchids (42.7%), followed by ferns (28.1%) and bromeliads (20.4%).
2) Phorophytes: The 120 climbed host trees belong to 32 tree species distributed in 25 genera and 21 families. Tree identification to the species level was possible in 53% of the cases, while another 44% were identified to genus level and 3% to family level.
Location of the 120 forest plots along the elevational gradient at the eastern slopes of Cofre de Perote mountain, Veracruz, Mexico (Suppl. material
Column label | Column description |
---|---|
Plot_ID | ID of each plot |
Vegetation | Vegetation type |
FUI | Forest-use intensity |
Site | Name of the study site |
Elevation.precise | Metres above sea level |
Latitude | Geographic coordinate |
Longitud | Geographic coordinate |
Tree.name | Scientific name of the central tree |
DBH | Diameter at breast height in centimetres |
Tree.height | Height of the tree in metres |
Distribution data of 271 vascular epiphyte species at each plot along the elevational gradient and three levels of forest-use intensity (n = 5 plots per forest-use intensity within each elevation) (Suppl. material
Column label | Column description |
---|---|
Plot_ID | ID of each plot |
Sp.code | Code for each scientific species name |
Frequency | The sum of incidences in the four nested subplots (maximum frequency per plot = 4) |
JZone1 | Johansson zone 1 |
JZone2a | Johansson zone 2a |
JZone2b | Johansson zone 2b |
JZone3 | Johansson zone 3 |
JZone4 | Johansson zone 4 |
JZone5 | Johansson zone 5 |
Frequency.J.zones | The sum of incidences in the Johansson zones (maximum frequency = 5) |
Single leaf trait measurements (leaf area, leaf density, specific leaf area and leaf dry matter content) per 474 individuals of 102 species and a total of 1595 leaves (Suppl. material
Column label | Column description |
---|---|
Site | Name of the study site |
FUI | Forest-use intensity |
Sp.code | Code for each scientific species name |
Ind.number | Number of the individual |
Leaf.number | Number of the leaf |
LA | Leaf area |
LD | Leaf density |
SLA | Specific leaf area |
LDMC | Leaf dry matter content |
Chemical leaf trait measurements (leaf nitrogen content, leaf phosphorus content, leaf carbon content, nitrogen isotope ratio and carbon isotope ratio) per 102 species (Suppl. material
Column label | Column description |
---|---|
Site | Name of the study site |
FUI | Forest-use intensity |
Sp.code | Code for each scientific species name |
Leaf nitrogen | Leaf nitrogen content |
Leaf carbon | Leaf carbon content |
Leaf.phosphorus | Leaf phosphorus content |
Delta15N | Nitrogen isotope ratio |
Delta13C | Carbon isotope ratio |
Species scientific name and its corresponding family and species code (Suppl. material
Column label | Column description |
---|---|
Species.code | Code for each scientific species name |
Species.name | Scientific name of the species |
Family | Family of the species |
We provide the description of the content and structure of each supplementary material in Table
Data documentation with information that describes the content and structure of each of the previous tables. The source of standardisation for each term used is provided in the Standardized according to column based on the Darwin Core glossary and the Thesaurus of Plant Characteristics (TOP). The name of the standardised term in the Standardized Term column. The term used in the present study in the Term in this study column. A definition is provided in the Definition column (following the Darwin Core, Thesaurus of Plant Characteristics or the given reference) and, if applicable, the unit of measurement in the Unit column.
Standardised according to |
Standardised Term |
Term in this study |
Definition |
Unit |
Darwin Core |
Family |
Family |
The full scientific name of the family in which the taxon is classified. |
|
Darwin Core |
Habitat |
Vegetation |
A category or description of the habitat in which the Event occurred. |
|
Darwin Core |
locationID |
Plot_ID |
An identifier for the set of location information (data associated with dcterms: Location). May be a global unique identifier or an identifier specific to the dataset. |
|
Darwin Core |
Locality |
Site |
The specific description of the place. Less specific geographic information can be provided in other geographic terms (higherGeography, continent, country, stateProvince, county, municipality, waterBody, island, islandGroup). This term may contain information modified from the original to correct perceived errors or standardise the description. |
|
Darwin Core |
organismID |
Sp.code |
An identifier for the Organism instance (as opposed to a particular digital record of the Organism). May be a globally unique identifier or an identifier specific to the dataset. |
|
Darwin Core |
organismQuantityType |
Frequency.subplot Frequency.J.zones |
The type of quantification system used for the quantity of organisms. |
|
Darwin Core |
scientificName |
Species name / Tree name |
The full scientific name, with authorship and date information, if known. When forming part of an Identification, this should be the name in lowest level taxonomic rank that can be determined. This term should not contain identification qualifications, which should instead be supplied in the IdentificationQualifier term. Note: we used a mixture of valid scientific names and informal names for plants not identified to the species level, therefore species names are not strictly Darwin Core-compliant. |
|
Darwin Core |
verbatimElevation |
Elevation |
The original description of the elevation (altitude, usually above sea level) of the Location. |
metres above sea level (m a.s.l.) |
Darwin Core |
DecimalLatitude |
Latitude |
The geographic latitude (in decimal degrees, using the spatial reference system given in geodeticDatum) of the geographic centre of a Location. Positive values are north of the Equator; negative values are south of it. Legal values lie between -90 and 90, inclusive. |
|
Darwin Core |
DecimalLongitude |
Longitude |
The geographic longitude (in decimal degrees, using the spatial reference system given in geodeticDatum) of the geographic centre of a Location. Positive values are east of the Greenwich Meridian; negative values are west of it. Legal values lie between -180 and 180, inclusive. |
|
Functional Diversity thesaurus |
Plant height trait |
Height |
the height (PATO:height) of a whole plant (PO:whole plant) |
m |
Functional Diversity thesaurus |
Leaf density |
Lamina density (LD) |
leaf dry mass per leaf volume |
g/cm3 |
Functional Diversity thesaurus |
Leaf area |
Leaf area (LA) |
the area (PATO:area) of a leaf (PO:leaf) in the one sided projection |
mm2 |
Functional Diversity thesaurus |
Leaf dry matter content |
Leaf dry matter content (LDMC) |
the ratio of the dry mass of a leaf (TOP:leaf dry mass) to its water saturated fresh mass |
g g-1 |
Functional Diversity thesaurus |
Specific leaf area |
Specific Leaf Area (SLA) |
the ratio of the area of a leaf (TOP:leaf area) to its dry mass (TOP:leaf dry mass) |
mm2 mg-1 |
Functional Diversity thesaurus |
Leaf nitrogen content per leaf dry mass |
Leaf nitrogen content |
The ratio of the quantity of nitrogen of a leaf per unit dry mass. |
% |
Functional Diversity thesaurus |
Leaf carbon content per leaf dry mass |
Leaf carbon content |
The ratio of the quantity of carbon of a leaf per unit dry mass. |
% |
Functional Diversity thesaurus |
Leaf phosphorus content per leaf dry mass |
Leaf phosphorus content |
The ratio of the quantity of phosphorus of a leaf per unit dry mass. |
% |
Craine et al. (2009) |
Nitrogen isotope ratio (d15N;‰) |
Nitrogen isotope ratio (d15N;‰) |
The ratio of 15N to14N of a leaf. |
‰ |
Dawson et al. (2002) |
Carbon isotope ratio (d13C;‰) |
Carbon isotope ratio (d13C;‰) |
The ratio of 13C to 12C of a leaf. |
‰ |
This study |
Forest-use intensity. (OG - old-growth forest, DF - degraded forest, SF - secondary forest) |
A level of forest fragmentation, subjected to ongoing disturbance and/or deforestation. |
||
This study |
DBH |
Diameter at breast height |
cm |
We thank A. Smith, A. Espejo-Serna, A. R. López-Ferrari, G. Mathieu, M. Cházaro-Bazáñez and P. Carrillo-Reyes for the taxa determination. We thank J. Veà, A. Bautista, M. Juarez-Fragoso, C. Carvajal, J. Gómez, D. Vergara, N. Velázquez, F. Calixto-Benites, M. Hernández, J. Ramírez and S. Guzmán for their help during fieldwork, N. Guerrero for statistical support, Margarete Watzka for processing leaf samples for isotopes, Norbert Wagner for processing leaf samples for phosphorus, Jürgen Grotheer and Petra Voight for providing access to the laboratory facilities at the Institute of Geography, University of Göttingen and R. Castro for helping with herbarium specimens. The German Academic Exchange Service (DAAD) provided a PhD scholarship (No. 91570360) to V. Guzmán-Jacob.
V.G.J and H.K conceived the main idea with input from D.C; V.G.J collected the data; and P.W revised the data. All authors made substantial contributions to the writing and editing of the manuscript.
Location of the 120 forest plots along the elevational gradient at the eastern slopes of Cofre de Perote mountain, Veracruz, Mexico.
Distribution data of 271 vascular epiphyte species at each plot along the elevational gradient and three levels of forest-use intensity (n = 5 plots per forest-use intensity within each elevation).
Single leaf trait measurements (leaf area, leaf density, specific leaf area and leaf dry matter content) per 474 individuals of 102 species and a total of 1595 leaves.
Chemical leaf trait measurements (leaf nitrogen content, leaf phosphorus content, leaf carbon content, nitrogen isotope ratio and carbon isotope ratio) per 102 species.
Species scientific name and its corresponding family and species code.