{ "model": { "rank": 6017, "code": "thing-q82551", "model_id": "vr.tr.nitrogen-cycle", "name": "nitrogen cycle", "purpose": "Let an agent explain the nitrogen cycle, relay processes, organisms, human impacts and management from ecology, soil science and environmental sources with assessments attributed, and distinguish the nitrogen cycle from the carbon and phosphorus cycles, nitrogen narcosis and the aquarium nitrogen cycle as a practical subset.", "family": "Thing Registry", "category": "Activities and processes", "status": "research-draft", "kind": "thing", "plane": "ACT", "domain": "ACT.PRC", "industry": "", "version": "", "url": "/models/thing/q82551/", "tier": 2, "score": 63, "payload": { "layer": "wikidata", "aliases": [], "aliasCount": 0, "merged": 0, "knownIn": 63, "facets": null, "markers": [], "lexicalClass": "", "senseRank": null, "alsoRegisteredAs": "vr.tr.nitrogen-cycle", "source": { "dataset": "wikidata", "item": "Q82551", "url": "https://www.wikidata.org/wiki/Q82551", "license": "CC0 1.0" } }, "research": { "vercy": "1.0-draft", "publication": { "status": "research-draft", "adjudicationStatus": "unreviewed", "publishableCanonical": false, "generatedAt": "2026-09-14T00:25:09Z", "providers": [ "Claude" ], "breadth": "written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify", "pass": 2, "wave": 4, "engine": "claude" }, "metaModel": { "id": "THING-Q82551", "registryId": "vr.tr.nitrogen-cycle", "name": "nitrogen cycle", "version": "0.2.0-wave.4", "entryKind": "thing", "family": "Thing Registry", "domain": [ "ACT.PRC" ], "status": "research-draft" }, "canonicalUrl": "https://ver.cy/models/thing/q82551/", "model": { "registry_id": "vr.tr.nitrogen-cycle", "name": "nitrogen cycle", "purpose": "Let an agent explain the nitrogen cycle, relay processes, organisms, human impacts and management from ecology, soil science and environmental sources with assessments attributed, and distinguish the nitrogen cycle from the carbon and phosphorus cycles, nitrogen narcosis and the aquarium nitrogen cycle as a practical subset.", "definition": "The biogeochemical cycle by which nitrogen moves between the atmosphere, soils, water and living organisms, through nitrogen fixation by bacteria and lightning converting atmospheric N2 into ammonia, nitrification by microbes oxidising ammonia to nitrite and nitrate, assimilation into proteins and nucleic acids, ammonification during decomposition, and denitrification and anammox returning nitrogen gas to the air; since the Haber-Bosch process was industrialised in 1913, human production of reactive nitrogen for fertiliser has roughly doubled nitrogen inputs to land, causing water pollution, eutrophication and nitrous oxide emissions, a planetary boundary concern, with assessments attributed.", "what_it_is_for": "Understanding nitrogen movement in ecosystems.", "affordances": [ "explain processes and organisms", "relay human impacts", "describe management approaches", "distinguish related cycles" ], "distinguishing_features": [ "Microbial transformations", "Fixation bottleneck", "Human amplification", "Pollution consequences" ], "appearance": "Not a physical object; illustrated as flows between air, soil, water and life.", "visual_identification": [ "Movement of nitrogen through Earth systems", "Nitrogen cycle, N cycle", "The carbon cycle moves carbon; the phosphorus cycle has no major gas phase; nitrogen narcosis is a diving effect; aquarium cycling is a practical application" ], "physical_properties": [ { "quantity": "atmosphere nitrogen", "typical_range": "about 78", "unit": "percent", "note": "by volume" }, { "quantity": "Haber-Bosch industrialised", "typical_range": "1913", "unit": "year", "note": "BASF Oppau" }, { "quantity": "anammox discovered", "typical_range": "1990s", "unit": "note", "note": "" } ], "families_and_kinds": [ "nitrogen fixation", "nitrification", "denitrification", "ammonification", "anammox" ], "related_models": [ { "relation": "is a kind of", "target": "biogeochemical cycle", "why": "in registry terms" }, { "relation": "includes", "target": "nitrogen fixation", "why": "" }, { "relation": "is altered by", "target": "Haber process", "why": "" }, { "relation": "is contrasted with", "target": "carbon cycle", "why": "" } ], "identifiers": [], "standards_and_regulation": [ "EU Nitrates Directive", "Water quality standards for nitrate", "Fertiliser regulations" ], "failure_modes_and_hazards": [ "Nitrate pollution of drinking water", "Eutrophication and dead zones", "Partisan framing of farming regulation" ], "in_scope": [], "out_of_scope": [], "characteristics": [] }, "sources": [], "structure": { "bundles": [ { "id": "understand", "name": "Understand", "description": "What the nitrogen cycle is.", "rationale": "Science.", "layers": [ { "id": "definition", "name": "Definition", "description": "Definition.", "findings": [ { "id": "definition-finding", "name": "Definition", "description": "Definition.", "questions": [ { "text": "What is the nitrogen cycle, and how does it differ from the carbon and phosphorus cycles, nitrogen narcosis and aquarium cycling?", "kind": "definition" }, { "text": "Is the question about ecology, farming, pollution or aquariums?", "kind": "boundary" } ] } ] }, { "id": "processes", "name": "Processes", "description": "Processes.", "findings": [ { "id": "processes-finding", "name": "Processes", "description": "Processes.", "questions": [ { "text": "What are fixation, nitrification, assimilation, ammonification, denitrification and anammox?", "kind": "definition" }, { "text": "Which entry fits the specific process?", "kind": "action" } ] } ] } ] }, { "id": "biology", "name": "Biology", "description": "Microbes.", "rationale": "Science.", "layers": [ { "id": "fixation", "name": "Fixation", "description": "Nitrogen fixation.", "findings": [ { "id": "fixation-finding", "name": "Fixation", "description": "Fixation.", "questions": [ { "text": "How do Rhizobium and other bacteria fix nitrogen with nitrogenase?", "kind": "provenance" }, { "text": "Which references are standard?", "kind": "provenance" } ] } ] }, { "id": "nitrifiers", "name": "Nitrifiers", "description": "Nitrifying microbes.", "findings": [ { "id": "nitrifiers-finding", "name": "Nitrifiers", "description": "Nitrifiers.", "questions": [ { "text": "Which microbes carry out nitrification and denitrification?", "kind": "provenance" }, { "text": "Which sources are cited?", "kind": "provenance" } ] } ] } ] }, { "id": "human", "name": "Human impact", "description": "Human impact.", "rationale": "Attribution.", "layers": [ { "id": "haber", "name": "Haber-Bosch", "description": "Haber-Bosch.", "findings": [ { "id": "haber-finding", "name": "Haber-Bosch", "description": "Haber-Bosch.", "questions": [ { "text": "How did the Haber-Bosch process transform food production and the nitrogen cycle?", "kind": "provenance" }, { "text": "Which entry fits Haber process?", "kind": "action" } ] } ] }, { "id": "pollution", "name": "Pollution", "description": "Nitrogen pollution.", "findings": [ { "id": "pollution-finding", "name": "Pollution", "description": "Pollution.", "questions": [ { "text": "What do assessments say about nitrogen pollution and planetary boundaries, and what policies are debated, with positions attributed?", "kind": "provenance" }, { "text": "Is the presentation neutral and attributed?", "kind": "boundary" } ] } ] } ] }, { "id": "context", "name": "Context", "description": "Applications.", "rationale": "Context.", "layers": [ { "id": "aquarium", "name": "Aquarium", "description": "Aquarium cycling.", "findings": [ { "id": "aquarium-finding", "name": "Aquarium", "description": "Aquarium.", "questions": [ { "text": "How do aquarists establish the nitrogen cycle to protect fish?", "kind": "provenance" }, { "text": "Which entry fits fishless cycling?", "kind": "action" } ] } ] }, { "id": "farming", "name": "Farming", "description": "Nutrient management.", "findings": [ { "id": "farming-finding", "name": "Farming", "description": "Farming.", "questions": [ { "text": "How do cover crops and precision fertilising reduce losses?", "kind": "provenance" }, { "text": "Which entry fits nutrient management?", "kind": "action" } ] } ] } ] } ] }, "openQuestions": [ "Should each process be a separate entry?", "How should planetary boundary assessments be linked?", "How should nitrogen policy debates be presented?" ], "statistics": { "bundles": 4, "layers": 8, "findings": 8, "questions": 16 } }, "draft": { "generator": "vr.draft.v3", "status": "draft-generated", "researched": false, "archetype": "abstract concept", "method": "Written from the archetype playbook - what this kind of thing needs beyond identity and provenance - and from the structure that recurred across 6,333 models already researched by two engines. Applied to this entry by rule. No source was read for this thing and no claim here is researched. This entry carries no facets of its own, so they were inferred from its domain - a guess about a whole domain applied to one thing.", "facetsInferred": true, "nextPass": "A researcher replaces this draft with a sourced specification. Treat every sentence below as a proposal to argue with.", "purpose": "Give an agent a durable, checkable way to recognise a nitrogen cycle, record what state it is in, and decide what may be done with it.", "whatItIs": "Let an agent explain the nitrogen cycle, relay processes, organisms, human impacts and management from ecology, soil science and environmental sources with assessments attributed, and distinguish the nitrogen cycle from the carbon and phosphorus cycles, nitrogen narcosis and the aquarium nitrogen cycle as a practical subset.", "characteristics": { "substance": "activity", "origin": "conceptual", "agency": "inert" }, "whatYouCanDoWithIt": [ "observed and measured" ], "distinguishingFeatures": [ "Described in 63 Wikipedia languages, which is a measure of how widely the thing is known, not of how important it is." ], "openQuestionsForResearch": [ "Which of the bundles below does a real task actually need, and which are ceremony?", "What does this thing have that the facets do not capture at all?", "Which neighbouring kind is most often confused with a nitrogen cycle, and on what evidence are they told apart?" ], "whatItIsMadeOf": "something that happens over time", "physicalCharacter": [ "Does nothing on its own; everything it does, something else did to it.", "These come from the domain this entry sits in rather than from the entry itself, so treat them as a first guess about the whole domain applied to one thing." ], "whatCanBeDoneWithIt": [ "observe it, measure it, record its state" ], "howItIsRecognised": [ "Nothing to see. What is recognised is an instance of it, and which instances count is exactly what is argued about." ], "relatedModels": [], "standing": "Described in 63 Wikipedia languages, which measures how widely it is written about rather than how important or how common it is.", "structure": { "bundles": [ { "id": "identity-and-classification", "name": "Identity, naming and classification", "description": "How an agent tells one nitrogen cycle from another, and a nitrogen cycle from things that resemble it.", "rationale": "Recognition comes before every other claim. Without stable identity nothing else in the model can be trusted to be about the same thing twice.", "layers": [ { "id": "naming-and-identifiers", "name": "Names and identifiers", "description": "The names this thing goes by and the identifiers that survive translation and time.", "findings": [ { "id": "preferred-name-and-aliases", "name": "Preferred name, aliases and local names", "description": "Which name to use, which names mean the same thing, and which merely sound similar.", "questions": [ { "id": "preferred-name-and-aliases-q01", "text": "What identifies and describes the name of a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "preferred-name-and-aliases-q02", "text": "Who or what asserted this about the name of a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "preferred-name-and-aliases-q03", "text": "What may an agent decide or do once the name of a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] }, { "id": "stable-identifiers", "name": "Stable identifiers and external keys", "description": "Identifiers that keep pointing at this kind of thing across systems and languages.", "questions": [ { "id": "stable-identifiers-q01", "text": "What identifies and describes an identifier for a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "stable-identifiers-q02", "text": "Who or what asserted this about an identifier for a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "stable-identifiers-q03", "text": "What may an agent decide or do once an identifier for a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "classification-and-granularity", "name": "Classification and granularity", "description": "Where a nitrogen cycle sits among kinds, and how finely a task needs to cut it.", "findings": [ { "id": "kind-and-parents", "name": "Kind, parents and neighbouring kinds", "description": "The classes this thing belongs to and the ones it is next to.", "questions": [ { "id": "kind-and-parents-q01", "text": "What identifies and describes the kind of a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "kind-and-parents-q02", "text": "Who or what asserted this about the kind of a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "kind-and-parents-q03", "text": "What may an agent decide or do once the kind of a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] }, { "id": "distinguishing-features", "name": "Distinguishing features", "description": "What separates a nitrogen cycle from the things most often confused with it.", "questions": [ { "id": "distinguishing-features-q01", "text": "What identifies and describes what distinguishes a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "distinguishing-features-q02", "text": "Who or what asserted this about what distinguishes a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "distinguishing-features-q03", "text": "What may an agent decide or do once what distinguishes a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "state-and-lifecycle", "name": "State and lifecycle", "description": "The states a nitrogen cycle passes through and the events that move it between them.", "rationale": "Most decisions about a thing depend on what state it is in now, which is a claim with a time on it, not a property.", "layers": [ { "id": "lifecycle-stages", "name": "Lifecycle stages", "description": "From coming into existence to ceasing to be one of these.", "findings": [ { "id": "stages-and-transitions", "name": "Stages and transitions", "description": "The stages worth naming and what moves a nitrogen cycle between them.", "questions": [ { "id": "stages-and-transitions-q01", "text": "What identifies and describes the lifecycle of a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "stages-and-transitions-q02", "text": "Who or what asserted this about the lifecycle of a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "stages-and-transitions-q03", "text": "What may an agent decide or do once the lifecycle of a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "observations-and-status", "name": "Observations and current status", "description": "What is observed about a nitrogen cycle, how often and by whom.", "findings": [ { "id": "observation-record", "name": "Observation record", "description": "How an observation of a nitrogen cycle is recorded so that it can be superseded rather than overwritten.", "questions": [ { "id": "observation-record-q01", "text": "What identifies and describes an observation of a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "observation-record-q02", "text": "Who or what asserted this about an observation of a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "observation-record-q03", "text": "What may an agent decide or do once an observation of a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "process-and-outcome", "name": "Process, inputs and outcome", "description": "How a nitrogen cycle proceeds, what it needs and what it leaves behind.", "rationale": "An activity is known by its steps and its results, and both have to be recordable while it is still running.", "layers": [ { "id": "steps-and-sequence", "name": "Steps and sequence", "description": "The steps of a nitrogen cycle, their order and what may run in parallel.", "findings": [ { "id": "steps-and-preconditions", "name": "Steps, preconditions and completion", "description": "What has to be true before each step of a nitrogen cycle and what marks it done.", "questions": [ { "id": "steps-and-preconditions-q01", "text": "What identifies and describes a step of a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "steps-and-preconditions-q02", "text": "Who or what asserted this about a step of a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "steps-and-preconditions-q03", "text": "What may an agent decide or do once a step of a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "inputs-and-results", "name": "Inputs, resources and results", "description": "What a nitrogen cycle consumes and what it produces.", "findings": [ { "id": "inputs-and-outputs", "name": "Inputs, outputs and side effects", "description": "The resources a nitrogen cycle takes and the results it leaves, wanted or not.", "questions": [ { "id": "inputs-and-outputs-q01", "text": "What identifies and describes the inputs and results of a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "inputs-and-outputs-q02", "text": "Who or what asserted this about the inputs and results of a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "inputs-and-outputs-q03", "text": "What may an agent decide or do once the inputs and results of a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "definitions-in-contest", "name": "Definitions and who holds them", "description": "What nitrogen cycle is taken to mean, and by whom.", "rationale": "When a field disagrees about a concept, the disagreement is the content. A model that picks one definition silently destroys the information.", "layers": [ { "id": "competing-definitions", "name": "Competing definitions", "description": "The main readings and the traditions behind them.", "findings": [ { "id": "definition-map", "name": "Definitions and their holders", "description": "Each definition with the school or body that holds it.", "questions": [ { "id": "definition-map-q01", "text": "Which definitions of nitrogen cycle are in use, and which tradition or body holds each?", "kind": "definition" }, { "id": "definition-map-q02", "text": "What turns on the difference between them in practice?", "kind": "boundary" } ] } ] }, { "id": "operationalisation", "name": "Operationalisation", "description": "How it is measured or applied when it has to be.", "findings": [ { "id": "operational-record", "name": "Measures and proxies", "description": "Instruments and indicators used to stand in for it.", "questions": [ { "id": "operational-record-q01", "text": "How is nitrogen cycle operationalised or measured in practice, and by what instrument?", "kind": "measurement" }, { "id": "operational-record-q02", "text": "What does that operationalisation leave out, and when does that matter?", "kind": "boundary" } ] } ] } ] }, { "id": "instances-and-use", "name": "Instances, use and consequence", "description": "What counts as an instance of nitrogen cycle and what follows from calling something that.", "rationale": "Applying a concept is an act with consequences, so a model must say what the label licenses and what it does not.", "layers": [ { "id": "instances", "name": "What counts as an instance", "description": "Clear cases, borderline cases and non-cases.", "findings": [ { "id": "instance-tests", "name": "Tests for an instance", "description": "What would settle whether something falls under it.", "questions": [ { "id": "instance-tests-q01", "text": "What would settle whether something is an instance of nitrogen cycle?", "kind": "boundary" }, { "id": "instance-tests-q02", "text": "Which borderline cases are argued about, and on what grounds?", "kind": "definition" } ] } ] }, { "id": "consequence", "name": "Consequence of application", "description": "Rights, duties or decisions that follow from the label.", "findings": [ { "id": "consequence-record", "name": "What the label licenses", "description": "What an agent may do once something is classified this way.", "questions": [ { "id": "consequence-record-q01", "text": "What follows practically once something is treated as nitrogen cycle?", "kind": "action" }, { "id": "consequence-record-q02", "text": "What must an agent not infer from the label alone?", "kind": "action" } ] } ] } ] }, { "id": "provenance-and-evidence", "name": "Provenance, evidence and time", "description": "Where every claim about a nitrogen cycle came from and when it held.", "rationale": "A claim without a source and a time cannot be superseded, only overwritten, and an agent that overwrites loses the ability to explain itself.", "layers": [ { "id": "source-and-authority", "name": "Source and authority", "description": "Who said it, on what evidence, and how strongly.", "findings": [ { "id": "claim-provenance", "name": "Claim provenance and confidence", "description": "The authority behind each claim about a nitrogen cycle and how confident it is.", "questions": [ { "id": "claim-provenance-q01", "text": "What identifies and describes a claim about a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "claim-provenance-q02", "text": "Who or what asserted this about a claim about a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "claim-provenance-q03", "text": "What may an agent decide or do once a claim about a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "time-and-versions", "name": "Time, versions and supersession", "description": "When a claim was true, when it was learnt, and what replaced it.", "findings": [ { "id": "validity-and-supersession", "name": "Validity period and supersession", "description": "How an old claim about a nitrogen cycle is retired without being erased.", "questions": [ { "id": "validity-and-supersession-q01", "text": "What identifies and describes the validity of a claim about a nitrogen cycle, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "validity-and-supersession-q02", "text": "Who or what asserted this about the validity of a claim about a nitrogen cycle, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "validity-and-supersession-q03", "text": "What may an agent decide or do once the validity of a claim about a nitrogen cycle is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] } ] }, "statistics": { "bundles": 6, "layers": 12, "findings": 14, "questions": 38 } } } }