Contribution to the Contribution to the development of a LADA development of a LADA

indicator toolboxindicator toolboxby F.R. Berdingby F.R. Berding

Steering Committee Meeting and Technical Steering Committee Meeting and Technical Workshop of the LADA project Workshop of the LADA project

28 November – 1 December 2006 28 November – 1 December 2006 FAO, Rome, ItalyFAO, Rome, Italy

SummarySummary• Background• Framework for developing indicators • Definitions • Indicator toolbox

– Levels– Stratification/mapping– Categories– Aggregation– Selection of indicators

• Conclusions

DefinitionsDefinitions

• Land: all attributes of the biosphere immediately above

or below the earth surface • Drylands: areas having a ratio of P/PET between 0.05

and 0.65 • Land degradation: reduced capacity of the land to

perform ecosystem functions and services that support society and development

• Indicator: statistics or measures that relate to a condition, change of quality, or change in state of something valued

Indicator toolboxIndicator toolbox

• Minimum set of ‘universal’ indicators• Can be measured at local and global scale• Allow for extrapolation at these different

scales. • Are relatively easy to measure or obtain• Are related to several conditions of the

land in such a way that the set of indicators, even if not exhaustive, can describe the system in a cost effective way

LevelsLevels

• LADA is about assessing land degradation at a global scale and a pilot country scale.

• In order to assess and to monitor land degradation indicators are needed:- to follow historical trends (mainly at the global level)

- to establish a baseline for indicators at local level.• These indicators need to be linked in a causal scheme

(for which LADA has adopted the DPSIR). • This paper is mainly about indicators to serve at the

local level but which can be extrapolated to the national level.

Stratification/mappingStratification/mapping

• Cost-effectiveness can be achieved by extrapolating results to nearby areas where no such detailed investigation can be undertaken because of the high costs involved.

• Stratification in this respect is useful because by superimposing different attributes of land, map units can be obtained that can be considered relevant and homogeneous, e.g. agro-ecological zones and cells, and capture the main factors that may influence land degradation.

CategoriesCategories

• The definition of land implies that land degradation assessment has to consider processes and/or issues that affect climate, soil, terrain, water and vegetation resources.

• Biodiversity loss is considered an ‘Impact’ of land degradation processes (loss of habitat, fragmentation …)

Aggregation (1)Aggregation (1)

Example of climate change, described by the World Resources Institute (WRI, 1995):

• Greenhouse gas emissions are seen as the pressure while concentrations in the atmosphere reflect the state of the atmosphere.

• The main greenhouse gases released by human activities are carbon dioxide, methane, nitrous oxide and haloalkenes (e.g. chlorofluorocarbons).

Aggregation (2)Aggregation (2)

• Without aggregation there would be one indicator for each of these gases.

• Decision makers need more compact information.

• The (sub)indicators for each of the GHGs are aggregated to form one indicator for climate change

Aggregation (3)Aggregation (3)• Concentrations of carbon dioxide, methane, nitrous

oxide and haloalkenes are measured.• Two factors are combined in the Global Warming

Potential (GWP) of each gas: how long do they remain in the atmosphere and how well do they absorb the heat radiated by the earth?

• The GWP is used as a weighting factor for emissions of that gas.

• The weighted summation of the GHGs, expressed as CO2 equivalents, forms the indicator for climate change.

Selection of indicators (1)Selection of indicators (1)• Climate resources

Pressure indicators:- Natural calamities indicator which informs about the frequency of extreme climatic events.- Land cover/land use change indicator which informs about changes due to extreme events.

State indicators: all three proposed state indicators revolve around water

- Aridity index- Rainfall variability- Soil moisture.

Selection of indicators (2)Selection of indicators (2)

• Soil resources (pressure)Pressure indicators:- Nutrient balance (measure for nutrient depletion/mining)- Land cover/land use change (measure for over-exploitation)- Emission of contaminating substances (measure for the release of polluting substances by various sectors)- Soil sealing (measure for urbanization)

Selection of indicators (3)Selection of indicators (3)

• Soil resources (state)State indicators:- Soil fertility (farmer field assessment/field kit)

- Soil health (aggregated indicator based on the field assessment of 10 soil parameters, see below)

- Soil loss (aggregated indicator based on the field assessment of sheet, rill, gully and wind erosion)

- Soil salinity (field assessment/field kit)

- Soil contamination (POPs and heavy metals)

Selection of indicators (4)Selection of indicators (4)

• Terrain resourcesPressure indicators:- Cultivated sloping land indicator, which indicates the % of land cultivated on slopes with gradient > 10% - Natural calamities indicator, which informs about the frequency of calamities such as volcanic eruptions and earth quakes/tsunamis- Land cover/land use change indicator, which indicates the area affected and the nature of the phenomenon State indicators: see Soil resources

Selection of indicators (5)Selection of indicators (5)

• Water resourcesPressure indicators:- Water consumption indicator (per sector)

- Emission of contaminating substances (measure for the release of polluting substances by various sectors)

State indicators:- Water availability indicator (available freshwater per capita)

- Ground water level indicator (field/remote sensing)

- Water contamination indicator (eutrophication, POPs and heavy metals)

- Water salinity indicator (TDS or EC measurement).

Selection of indicators (6)Selection of indicators (6)

• Vegetation resourcesPressure indicators:- Land cover/land use change indicator (area affected by fires, deforestation, denudation through overgrazing). - Stocking rate indicator (number of tropical livestock units per square km or vice versa).

State indicator- Vegetation activity indicator (to monitor vegetation conditions over the years and detect trends)

Example of a Soil resources state indicatorExample of a Soil resources state indicator• Soil health (1)The following parameters are assessed (small 40 cm deep pit):

- Soil depth (<25, 25-50, 50-100, >100 cm)

- Soil structure (grade)

- Tillage pan/compaction (consistence, porosity)

- Texture (assessment table; sand, loam, clayloam and clay groups)

- Coarse fragments (<15, 15-40, 40-80, >80 %)

- Rooting condition (inside/outside structural elements, number of roots)

- Organic matter (value: from white to black)

- Biological activity (number of earthworms and other biological features)

- Soil surface crusts (physical or biological; thickness, % cover)

- Sodicity (black dispersed organic matter, waterlogging, columnar

structure, tunnel/pipe erosion, corrosion of road furniture)

Example of a Soil resources state indicatorExample of a Soil resources state indicator

• Soil health (2)

Each parameter is given a rating: 0, 1, 2 or 3

A weighting factor is introduced: soil depth and texture for instance are given a weighting factor of 2 which means that in the summary table the original rating is multiplied by 2.

Maximum score is 42, minimum score is 0

Example of a Soil resources state indicatorExample of a Soil resources state indicator

• Soil health (3)• Final field assessment:• Score of >35: very good (No severe or moderate

constraints)• Score of 29 – 35: good (No severe constraints)• Score of 21 – 28: medium• Score of 11 – 20: poor• Score of ≤ 10: very poor

Presentation of indicatorsPresentation of indicators

• The indicators are presented according to a format (table) proposed by the FAO LADA Team and comprising the following subdivision:

• 1. Definition• 2. Position within the DPSIR framework• 3. Target and political pertinence• 4. Methodological description and basic definition • 5. Evaluation of data needs and availability • 6. Institutions that participated in developing the indicator • 7. Practical applications of the indicator • 8. Additional information

Conclusions (1)Conclusions (1)

1. Eight pressure and 13 state indicators are proposed.

2. Some indicators require aggregation, e.g. of soil resources related parameters (or sub-indicators).

3. All indicators can be processed into digital maps.

4. The collection of data for pressure indicators can be done at national level with the help of remote sensing and statistical techniques and is relatively cheap.

Conclusions (2)Conclusions (2)

5. The collection of data for state indicators can either be done with the help of:

5.1 Remote sensing and statistical data (relatively cheap): aridity index, rainfall variability, soil moisture, vegetation activity, water availability) or

5.2 Field surveys/measurements and farmers’ knowledge (relatively expensive): soil fertility, soil health, soil loss, soil salinity, soil contamination, water contamination, groundwater level, water salinity

5.3 In the latter case prior stratification is necessary for extrapolation from local to national level.