Innovation
Species traits, environment and spatial data
The key to understanding changes in biodiversity is in understanding
the processes that affect distribution and abundance of species.
Today, for plant species the distribution pattern and changes
therein are mostly available, in e.g. national inventories,
permanent plots, vegetation maps. The result is a species-site
matrix revealing the number of species in a site (the biodiversity)
and the distribution of species across sites (rarity). Understanding
this dynamic pattern of biodiversity and rarity requires two other
sets of information: (i) the corresponding environmental data for
the site vector and (ii) the persistence and dispersal traits for
the species vector that are relevant for the spatial dynamics in the
environmental pattern. That information is represented by a
site-environmental factors matrix and a species-trait matrix that
serve as explanatory variables (Fig. 1). The species-trait matrix
contains the life-history of a species (the sum of its traits) and
the distribution of a trait over the flora of a region. Given the
trade-off structure of life-history traits, the species - trait
matrix will reveal species - trait clusters also known as functional
types. Explaining biodiversity in terms of such functional types
– in this case persistence, regeneration and dispersability
– is the underlying principle on which we base our database
initiative. |
Figure 1 (click to enlarge). Three collated matrices are needed to
explain and assess biodiversity and rarity.The species - site matrix
and the site - environmental factors matrix are to be assembled from
field data, while the LEDA Traitbase will allow researchers and
stakeholders to build the species - trait matrix for their field
data set.
LEDA’s potential to address biodiversity changes at a
European scale
Agriculture and urbanisation as well as abandonment and segregation
of land uses have drastically altered and are still altering the
European landscape. This has led to an accelerated loss of wildlife
habitat and to the increasing isolation of habitat remnants in
Europe and throughout the world. One common feature of recent land
use changes is that they affect large areas and large species pools
at a time. Also, theories on the dynamics of spatially structured
populations and empirical evidence tell us that changes in local
biodiversity can only be understood if the larger regional species
pools and their spatio - temporal dynamics are considered. By
covering over 3000 species, the LEDA Traitbase provides a tool for
the analysis of changes in local biodiversity based on the
availability of species in larger areas and the life history
features that define their spatio-temporal dynamics.
Innovation through a transnational initiative to build a
database on plant species traits
Currently, we are aware of hundreds to thousands of published papers
with information on aspects of the life history of selected plant
species in Europe. Generalising from all the single bits of
information is an urgent task for future scientific development.
Based on the compilation of their relevant life history features,
species need to be put in a comparative context in order to extract
general principles about functional plant-environment relations.
At present there is a large number of biological and ecological
floras and databases in Europe covering various aspects of plant
life history. However, only a few are relatively comprehensive and
include more than 200 species.
In general, currently accessible databases and biological floras are
restricted to certain regions of Europe, and cover only a limited
number of species or traits. They use different software systems and
most of them offer poor retrieval functions. This called for a
transnational initiative towards a complete species-trait matrix
that is easily accessible and retrievable on the web.
Innovation in the choice of the LEDA traits as predictors for
the plant species response to the environment
A major thrust of the LEDA Traitbase is directed towards
persistence, regeneration and dispersability. Persistence and
regeneration of the individual plant translates into local
population inertia while dispersal translates into regional
immigration. The following table provides an overview on the traits
that are covered by the LEDA Traitbase with their functional
ecology:
Persistence:
- Plant height - Competitive ability.
-
- Leaf size, leaf distribution along the stem,
branching, shoot growth form - Competitive ability.
-
- Specific Leaf Area (leaf area per unit leaf
mass) - Growth rate, competitive ability.
-
- Tissue density - Growth rate, leaf life
span.
-
- Clonal extension and clonal growth form - Competitive
ability, persistence, clonal integration, storage.
-
- Type of vegetative regeneration - Response
to disturbance.
Regeneration:
- Plant life span, age of first flowering - Response
to disturbance, establishment, invasiveness
-
- Seed number per inflorescence / shoot
(quality & time) - Response to disturbance, establishment,
dispersal.
-
- Seed weight, size and shape - Dispersal,
establishment, seed bank longevity.
-
- Seed bank longevity - Generative
regeneration, response to disturbance, restoration.
Dispersability:
- Morphology of dispersal unit - Wind
dispersal, ecto- and endozoochorous dispersal
-
- Terminal velocity-Wind-dispersal.
-
- Attachment capacity of the dispersal unit,
digestion survival - Ecto- and endozoochorous dispersal.
-
- Buoyancy - Dispersal in running water.
|
| |
 Top of page |
