Title: Measuring biodiversity
1Measuring biodiversity
- Dr RJ (Bob) Scholes
- Chair, Global Terrestrial Observing System
- CSIR Environmentek
- PO Box 395, Pretoria 0001, South Africa
- bscholes_at_csir.co.za
2This paper will cover
- Theory of biodiversity observations
- Existing approaches and systems
- Approaches that may satisfy the goals
3Biodiversity 3 aspects x 3 levels
Structural
Landscape patterns
Physiognomy/habitat structure
(Noss 1994)
Population structure
Genetic structure
Genetic process
Genes
Demographic process
Compositional
Interspecific interactions
Species, populations
Functional
Landscape processes/ disturbances/
Communities/ecosystems
Landscape type
4At any level, diversity has at least two
components
- How many different types of things are present
- Elephant, rhino and lion is less diverse than
- Elephant, rhino, lion, leopard and buffalo
- How evenly they are represented
- 1000 elephants and 1 lion is less diverse than
- 500 elephants and 500 lions
5Academic ways of measuring biodiversity
- Species level
- Richness Total number of species in an area (?
diversity) - Species turnover along a gradient (? diversity)
- Ecosystem level
- Number of different habitats or ecosystems (?
diversity) - Genetic level
- Genetic homology
- Cladistic distance
6Policy ways of measuring biodiversity
- Extinction based (IUCN)
- Threatened species (Red Data Books)
- Area based (Millennium goals)
- Area under protection
- Area of a key habitat (eg Forest cover)
- Richness based
- Indicator groups or species eg CI Rapid
Biodiversity Assessment - Complementarity based
- Various conservation optimisation tools, eg CPLAN
- Various spatial representations
- Hotspots, last wild places
7Royal Society Report2003
- no sound basis exists for assessing
performance against these targets. - The fate of organisms not yet recognised by
science cannot be measured - Lack of baselines
- Biodiversity measures must be related to the
objectives of measurement
8Attributes of a good indicator
- Does it measure what it says it does?
- Sensitive, but not oversensitive
- Scale appropriate in time and space
- Well-understood model
- Reliable data available
- Monitoring systems in place
- Understandable by policymakers
- (NRC 2000)
9Natural Capital IndexRIVM/UNEP-WCMC/GEO-3
NCI ecosystem quality x ecosystem quantity
10Example NCI for The Netherlands
11 SA?MA Biodiversity Intactness Index
- Based on impacts on populations, rather than
extinctions - Considers a range of impacts
- Protected, sustainably used, unsust used,
partially transformed, transformed - Scale independent
- Applicable now, but amenable to incremental
improvement
Southern Africa Millennium Ecosystem Assessment
12SA?MA Algorithm
B biodiversity intactness index Cijk
populations of i under use k/ popn when
protected Ajk Area of land use k in ecosystem
j Rij Richness of taxon i in ecosystem j i
taxon, from 1 to t j ecosystem, from 1 to m k
land use type, from 1 to n
Needs Land cover, richness, impact matrix
13Worked exampleSouth Africa, biome resolution
14WWF Ecoregion database
867 biodiversity-based regions of the world Based
on best available information Species lists for
birds, mammals, reptiles, plants,amphibia
15Global land cover products
- Many are now available
- DISCover, FAO-FRA, GLC 2000, Modis
- Global coverage, resolution lt 1 km
- 20 m products available for key areas
- Methods and results convergence
- GOFC/GOLD (a GTOS panel)
- Mid 1990s baselines feasible, year 2000 baseline
in hand - Reliable expectation of year 2010 repeat
16What GTOS can offerGlobal Terrestrial Observing
System
- Biodiversity is one of the five mandated topics
covered by GTOS - Land, freshwater, cryosphere
- Close collaboration with GOOS on coasts
- GOOS covers open ocean
- TEMS database
- biodiversity module
- Biodiversity network methods harmonised
- GOFC/GOLD
- Land cover dynamics, especially forests
17TEMS Terrestrial Ecosystem Monitoring Sites
Who, what, where
- Web directory of 1,600 sites and 55 networks in
110 countries that carry out long-term
terrestrial ecosystem monitoring of 110 variables
http//www.fao.org/gtos/tems
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19TEMS Biodiversity module
Variables specific to biodiversity
- Colonization of habitat by invasive species
- Habitat conversion
- Habitat fragmentation
- Indicator species
- Pollinator species
- Species Richness
- Threatened Species
- Many of the other 115 variables in TEMS are also
directly linked to Biodiversity.
20The CBD and WSSD goalsCBD CoP VII/26, WSSD
Implementation Plan
- ..significantly reduce the rate of loss of
biodiversity by 2010 - This is a double differential problem
- Change in a rate
- Requires at least 3 snapshots in time to solve
21Global strategy for plant conservationCBD CoP
VI/9 April 2002
- Accessible list of plant species
- Assess status of all species
- Understand conservation needs for threatened
species - 10 of each ecological region, 50 of species
conserved in situ - 90 threatened species cons ex situ
- 30 of production lands managed consistent with
conservation goals
22UN Millennium Goals
- reverse the loss of environmental resources
- Proposed indicators
- Proportion of land area covered by forest
- Proportion of land area protected for
biodiversity conservation - These indicators are measurable, but not
necessarily sensitive to the goal
23Pragmatic issues
- For the purpose of evaluating progress towards
the goals, biodiversity measurements - Dont have to be perfect, just agreed
- Need to be based on activity rather than
stock measurements (cf UNFCCC) - Satellite-based land cover measurements, coupled
with sparse in-situ information in an explicit
way (a model) could do the job for terrestrial
systems
24A proposal
- Agree to develop an approach based on
- Land cover/use in 1995, 2000, 2005 and 2100
GOFC/GOLD WCMC - Richness within ecosystem units WWF Taxonomy
initiatives NGOs nations - An impact matrix (land use x taxa, per biome)
derived from site data, models and expert
judgement Diversitas GTOS - For test by 2005, and retrospective application
by 2010