desertification
Enable an agent to recognise desertification, assess evidence of dryland degradation and identify context-appropriate prevention, restoration and adaptation options.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
recalled by Codex without web access - no source was read
Researched by: Codex
Purpose and description
Enable an agent to recognise desertification, assess evidence of dryland degradation and identify context-appropriate prevention, restoration and adaptation options.
Desertification is land degradation in arid, semi-arid and dry sub-humid areas resulting from climatic variations, human activities and their interactions, involving loss of biological or economic productivity or ecological complexity.
It can be Assess whether a reported case meets a declared desertification definition and identify missing evidence.; Compare degradation assessments while exposing differences in baselines, indicators and spatial resolution.; Trace plausible climatic and land-management drivers and prioritise investigations that distinguish them.; Identify locations and land functions requiring prevention, restoration or adaptation.; Evaluate intervention options against ecological suitability, water constraints, land rights and livelihood effects.; Monitor recovery and revise an assessment when field observations contradict remote indicators..
Distinguishing features
A candidate instance must satisfy an explicitly adopted dryland definition; degradation alone does not establish desertification.
Low vegetation cover or low productivity alone is insufficient: evidence must distinguish degradation from a naturally sparse or low-productivity ecosystem.
A drought-associated decline requires assessment of recovery and lasting functional loss before it is treated as evidence of desertification.
Desertification does not require advancing sand dunes or conversion into a visually recognisable desert.
An ACT classification does not establish deliberate human action; climatic and human contributions require separate assessment.
Scope
+ Definitions of desertification and criteria for identifying eligible dryland areas.
+ Changes in soil, vegetation, water functioning and biological or economic productivity.
+ Interactions among climatic variability, land use and management pressures.
+ Spatial extent, severity, persistence, vulnerability and reversibility of degradation.
+ Effects on dryland livelihoods and evaluation of prevention, restoration and adaptation.
- Land degradation outside the adopted dryland boundary, owned by a broader land-degradation model.
- Desert ecosystems and their natural dynamics where degradation is not demonstrated.
- Drought as a climatic event independent of persistent land degradation.
- Climate change and aridification as broader climatic processes.
- Individual agricultural practices, water infrastructure and land-tenure systems except for their role in desertification.
Characteristics
- Definition and assessment convention
- Named authority, definition version, included functions and decision rules. Determines what qualifies and makes disagreements between assessments interpretable.
- Dryland eligibility
- Aridity class; precipitation-to-potential-evapotranspiration ratio, dimensionless; reference period and adopted thresholds. Separates desertification from degradation outside the selected dryland boundary.
- Affected extent
- Hectares or square kilometres, percentage of assessment area, mapping resolution and observation date. Locates the process and exposes scale-dependent differences in reported extent.
- Productivity trajectory
- Trend in a specified productivity indicator, its native units, assessment period and climate-adjustment method. Supports detection while distinguishing climatic fluctuations and management inputs from lasting functional change.
- Soil and water functional condition
- Improving, stable, declining or uncertain for separately assessed erosion, salinity, soil carbon, infiltration and water retention. Prevents a vegetation-only assessment from overlooking degradation mechanisms.
- Driver contribution
- Links to climatic and human pressures, with mechanism, timing, supporting evidence and attribution confidence. Connects observed degradation to plausible causes without equating correlation with responsibility.
- Recovery condition
- Recovering, persistently degraded, potentially reversible, suspected threshold crossing or unresolved. Guides intervention expectations and separates observed recovery from assumptions about reversibility.
- Livelihood dependence and exposure
- Affected groups linked to grazing, cropping, water access or other land functions, with seasonal dependence and access rights. Shows who experiences losses and who may bear the costs of intervention.
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.desertification
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 18 findings · 28 questions.
Definition and dryland boundary Establishes the sense of desertification and the geographic and functional conditions required for an instance.
Assessments cannot be compared when they silently use different definitions of drylands or degradation.
Definition and authority
Records the adopted definition and meaningful alternatives.
Adopted desertification concept
Capture whose definition applies, what constitutes degradation and where alternative frameworks would classify the same case differently.
- Which authority and version define desertification for this assessment, and which land functions does that definition include? definition
- Would another relevant scientific, policy or local interpretation include or exclude this case, and why? boundary
Dryland eligibility
Determines whether the assessed land falls inside the adopted climatic boundary.
Aridity classification
Record the aridity calculation, reference period and treatment of locations near or moving across a dryland boundary.
- Which precipitation and potential-evapotranspiration data, reference period and thresholds establish dryland eligibility? measurement
- How are hyper-arid areas, irrigated land and locations crossing the selected climatic boundary treated? boundary
Degradation evidence and trajectory Tests whether dryland functions have declined and how confidently that decline can be distinguished from variability.
Sparse vegetation, drought and indicator noise can otherwise be mistaken for desertification.
Baseline and persistence
Establishes an ecologically appropriate comparison and the duration of observed change.
Change relative to reference
Document the reference condition and evidence separating degradation from seasonal variation, drought response or a naturally sparse ecosystem.
- What historical period or comparable reference site establishes expected condition for this soil, vegetation and land-use setting? measurement
- Does functional loss persist after favourable rainfall returns, and what observation period supports that judgement? measurement
Converging indicators
Combines vegetation, soil and water evidence without assuming that one proxy represents all land functions.
Indicator agreement and ground checks
Record agreement, contradictions and independent checks among productivity trends, vegetation composition and soil-water measurements.
- Which observed changes in productivity, vegetation composition, erosion, salinity or infiltration support the degradation assessment? measurement
- Which field observations validate the mapped trends, and where could greening conceal declining soil or water function? provenance
Drivers and degradation mechanisms Connects pressures to the processes that reduce dryland function.
Effective responses depend on distinguishing the mechanism of damage from a list of coincident pressures.
Climate and management interactions
Assesses climatic exposure alongside grazing, cultivation, vegetation removal and water management.
Supported driver attribution
Represent candidate drivers as evidence-backed causal hypotheses with explicit alternatives and uncertainty.
- How did rainfall, heat and drought timing interact with grazing pressure, cultivation, vegetation removal or irrigation before the observed decline? provenance
- What comparison or causal analysis distinguishes management effects from climatic variability and their interaction? measurement
Soil-water-vegetation feedbacks
Identifies mechanisms that propagate damage or constrain recovery.
Mechanisms and recovery barriers
Capture locally supported pathways such as erosion, crusting, salinisation or vegetation loss, together with evidence for feedbacks.
- Which measured process links the identified pressure to reduced soil, water or vegetation function at this site? measurement
- What evidence shows that degradation sustains itself after the initiating pressure is removed, rather than merely recovering slowly? boundary
Extent, exposure and consequences Locates degradation and traces its ecological and livelihood effects across connected places.
A single severity score can hide fragmented hotspots, downstream effects and unequal losses.
Spatial pattern and connectivity
Records affected patches, their confidence limits and connections through wind, runoff or land use.
Mapped footprint and spillovers
Separate directly observed degradation from inferred spread and effects beyond the degraded area.
- What area is demonstrably degraded at the stated resolution, and how sensitive is that estimate to classification thresholds? measurement
- Which dust, sediment, runoff or displaced land-use effects connect degraded patches to other locations? boundary
Land functions and livelihoods
Assesses changes in ecological function and consequences for groups using the land.
Distributed functional losses
Record whose forage, harvest, water access or other benefits have changed and the evidence connecting those changes to degradation.
- Which land functions have declined, by how much and during which seasons? measurement
- Which groups experience those losses, and what evidence separates degradation effects from changes in markets, access rights or conflict? provenance
Response and recovery Links intervention choices to degradation mechanisms and verifies their ecological and social outcomes.
An intervention can improve one visible indicator while worsening water stress or restricting essential land access.
Intervention fit and feasibility
Assesses prevention, restoration and adaptation against local ecological conditions and decision rights.
Mechanism-matched response
Evaluate candidate responses using the diagnosed process, expected water demand, land rights and livelihood constraints.
- Which response addresses the demonstrated mechanism, and what local evidence supports its feasibility under expected rainfall and water availability? action
- Who can authorise and maintain the response, and how would it affect grazing mobility, customary access or downstream water users? action
Recovery verification and adjustment
Defines success and tests whether observed improvements are durable and attributable to intervention.
Durable functional recovery
Track soil, water, vegetation and livelihood outcomes against explicit expectations and climate variability.
- Which functional outcomes, comparison areas and monitoring duration would distinguish intervention success from a favourable rainfall period? measurement
- What evidence of continued degradation, water depletion or displaced pressure would trigger adjustment, cessation or a shift toward adaptation? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- This describes the environmental process; the supplied ACT.ACT domain code does not establish a narrower sense.
- The listed kinds are overlapping degradation mechanisms, not a universally standardized taxonomy.
- Attribution, baseline selection and thresholds remain assessment-dependent; SDG indicator 15.3.1 covers all land degradation and is not specific to desertification.
- Which of these check these first hold for the sense of desertification this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Vegetation degradation
- Wind-erosion-dominated degradation
- Water-erosion-dominated degradation
- Salinization-driven degradation
- Soil physical degradation, including compaction and crusting
- Which of these kinds and varieties hold for the sense of desertification this model covers, and on what evidence? provenance
Standards and regulation
Recalled without web access and unsourced; every item is a lead to verify.
- United Nations Convention to Combat Desertification (UNCCD): international treaty defining desertification and establishing obligations to combat it and mitigate drought effects.
- UNCCD Science-Policy Interface: Scientific Conceptual Framework for Land Degradation Neutrality.
- United Nations Sustainable Development Goal indicator 15.3.1, with UNCCD as custodian: proportion of land that is degraded over total land area.
- Which of these standards and regulation hold for the sense of desertification this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Planning sustainable grazing, cropping and soil conservation in drylands.
- Identifying priorities for land restoration and monitoring restoration outcomes.
- Supporting national UNCCD reporting and land degradation neutrality targets.
- Assessing threats to agricultural livelihoods, ecosystem services and food security.
- Combining satellite observations with field measurements and local knowledge to assess degradation.
- Which of these real-world use hold for the sense of desertification this model covers, and on what evidence? provenance
Typical measurements
Recalled without web access and unsourced; every item is a lead to verify.
- Aridity index: annual precipitation divided by potential evapotranspiration - Approximately 0.05-0.65 delineates the dryland climatic scope used by UNCCD; it does not measure degradation severity. - dimensionless
- Proportion of assessed dryland area classified as degraded - 0-100; results depend on the assessment period, baseline and classification method. - %
- Soil organic carbon stock - No universal range; comparisons require a specified soil depth and consistent sampling. - tonnes of carbon per hectare
- Which of these typical measurements hold for the sense of desertification this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Loss of productive topsoil, vegetation cover and agricultural productivity.
- Reduced infiltration and water retention, potentially increasing runoff and erosion.
- Salinization that limits plant growth and the usability of irrigated land.
- Dust emissions, habitat degradation and biodiversity loss.
- Misdiagnosis when temporary drought effects or rainfall-driven vegetation changes are treated as evidence of persistent land degradation.
- Which of these failure modes and hazards hold for the sense of desertification this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- In the Sahel, rainfall variability interacts with grazing, cultivation and land management; regional greening can coexist with local degradation.
- In irrigated drylands, inadequate drainage and salt accumulation can be major degradation mechanisms.
- In Mediterranean drylands, erosion, vegetation disturbance, fire and water pressures interact in locally variable ways.
- Which of these regional variation hold for the sense of desertification this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Land degradation - Land degradation can occur in any climatic zone; desertification denotes its occurrence within specified dryland zones.
- Drought - Drought is an episode of abnormal water shortage; desertification is degradation of land condition and productivity, which may persist beyond the episode.
- Aridification - Aridification is a shift toward a drier climate; desertification concerns degraded land and can occur without a long-term decrease in rainfall.
- Desert - A desert is an environmental or climatic region that may be naturally functioning; desertification neither requires sand dunes nor means simply the expansion of existing deserts.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of desertification this model covers, and on what evidence? provenance
What the second pass must settle
- Which authoritative definitions and assessment frameworks should anchor this registry entry, and where do their classifications materially diverge?
- Does an existing Vercy world model already cover desertification or own the relevant dryland-degradation concept?
- What persistence criteria and reference conditions are defensible across different dryland ecosystems and observation histories?
- How should conflicting productivity, vegetation, soil and water indicators be combined without concealing functional losses?
- Which degradation thresholds and intervention outcomes have sufficiently strong local evidence to support claims about reversibility?