Your TNFD assessment identified "water dependency" — but which water? From which ecosystems? Flowing through which services? "Nature" is not a useful category for disclosure. You need precision.
This guide introduces the stocks and flows framework: 15 ecosystem types (stocks) that generate 19 ecosystem services (flows). This is the vocabulary that makes nature-related disclosure specific, measurable, and actionable.
tl;dr
Stocks are what accumulates — the 15 ecosystem types that exist as natural capital (forests, wetlands, coastal systems). Flows are what circulates — the 19 ecosystem services that nature provides (clean water, climate stability, pollination). Your TNFD disclosure should map dependencies to specific stocks and flows, not vague references to "nature" or "biodiversity."
why stocks and flows matter for TNFD
TNFD requires disclosure of nature-related dependencies and impacts. But "we depend on nature" is not disclosure — it's a truism. Every company depends on nature.
Useful disclosure looks like:
| Vague | Specific |
|---|---|
| "We depend on water" | "Our Osaka facility depends on water abundance from the Yodo River system, sourced from temperate forest and inland wetland ecosystems" |
| "Biodiversity is important" | "Pollination services from grassland and shrubland ecosystems support 40% of our agricultural supply chain" |
| "We have climate risk" | "Climate stability services from boreal and temperate forests regulate the precipitation patterns our hydropower assets depend on" |
Stocks and flows provide the vocabulary for this specificity.
the 15 ecosystem stocks
Ecosystem stocks are the 15 distinct ecosystem types that constitute natural capital. Think of these as the asset classes of nature — each with different characteristics, risk profiles, and service generation.
| Stock | What It Is | Key Services |
|---|---|---|
| Tropical Forests | Equatorial broadleaf forests | Carbon storage, biodiversity, water regulation |
| Temperate Forests | Mid-latitude deciduous and mixed forests | Timber, carbon, watershed protection, habitat |
| Boreal Forests | Northern conifer forests | Massive carbon reserves, climate regulation |
| Grasslands | Prairies, savannas, meadows | Soil carbon, grazing, pollination |
| Shrublands | Scrub, chaparral, heath | Fire regulation, habitat, erosion control |
| Inland Wetlands | Marshes, swamps, peatlands | Water filtration, flood control, carbon storage |
| Rivers & Lakes | Freshwater systems | Water provision, fisheries, transport |
| Coastal Systems | Estuaries, mangroves, beaches | Storm protection, fisheries, blue carbon |
| Marine Systems | Open ocean, coral, deep sea | Fisheries, climate regulation, oxygen |
| Polar & Alpine | Ice caps, tundra, high mountains | Freshwater storage, climate regulation |
| Deserts | Arid and semi-arid regions | Mineral resources, solar potential, specialized biodiversity |
| Subterranean | Caves, aquifers, underground | Groundwater, carbon storage, minerals |
| Cultivated & Developed | Farmland, urban areas | Food production, managed ecosystems |
| Urban Open Space | Parks, gardens, urban green | Recreation, heat mitigation, stormwater |
| Rural Open Space | Pastures, buffer zones, hedgerows | Habitat connectivity, multi-use |
the 19 ecosystem service flows
Ecosystem service flows are what nature provides — the benefits that flow from stocks to human and economic systems. These are organized into three categories.
provisioning services (6)
Direct material outputs from ecosystems:
| Flow | What It Provides |
|---|---|
| Raw Materials | Timber, fiber, biological materials |
| Food | Crops, livestock, wild harvest, fisheries |
| Energy | Biomass, hydropower potential |
| Water Abundance | Freshwater quantity and availability |
| Healthy Soils | Productive soil for agriculture and ecosystems |
| Medicinal & Genetic | Pharmaceuticals, genetic resources |
regulating services (7)
Ecosystem processes that regulate environmental conditions:
| Flow | What It Regulates |
|---|---|
| Climate Stability | Carbon sequestration, temperature moderation |
| Clean Air | Air filtration, pollution absorption |
| Clean Water | Water purification, filtration |
| Risk Resilience | Flood control, storm buffering, disaster mitigation |
| Pollination | Crop and wild plant reproduction |
| Erosion Control | Soil retention, slope stability |
| Pest & Disease Control | Natural pest management, disease regulation |
cultural services (6)
Non-material benefits from ecosystems:
| Flow | What It Provides |
|---|---|
| Habitat | Support for species, biodiversity maintenance |
| Recreation & Experiences | Tourism, outdoor activities, nature access |
| Research & Learning | Scientific study, education |
| Aesthetic & Sensory | Scenic beauty, soundscapes, sensory experience |
| Art & Inspiration | Creative inspiration, cultural expression |
| Existence & Legacy | Intrinsic value, intergenerational bequest |
mapping dependencies: sector examples
Different sectors depend on different combinations of stocks and flows. Here's how Japanese TNFD adopters map to this framework:
beverages: suntory
Suntory's beverage production depends critically on water — but "water" spans multiple stocks and flows.
| Dependency | Stock | Flow |
|---|---|---|
| Production water | Rivers & Lakes, Subterranean | Water Abundance |
| Watershed health | Temperate Forests, Inland Wetlands | Clean Water, Water Abundance |
| Agricultural inputs | Cultivated & Developed, Grasslands | Food, Healthy Soils |
Suntory's Natural Water Sanctuary program invests in the temperate forest and inland wetland stocks that generate the water abundance and clean water flows their production depends on.
Source: Suntory TNFD Announcement
pulp & paper: oji holdings
Oji Holdings manages significant forest assets and depends on forest ecosystems for raw materials.
| Dependency | Stock | Flow |
|---|---|---|
| Fiber supply | Temperate Forests, Boreal Forests | Raw Materials |
| Water for processing | Rivers & Lakes | Water Abundance, Clean Water |
| Carbon management | Temperate Forests, Boreal Forests | Climate Stability |
Oji's TNFD analysis in their Integrated Report guides sustainable forest management across their holdings in Japan and overseas (including New Zealand).
Source: Oji Holdings Integrated Report 2024
manufacturing: nitto denko
Nitto Denko's materials manufacturing depends on ecosystem services throughout the supply chain.
| Dependency | Stock | Flow |
|---|---|---|
| Raw material inputs | Multiple (varies by product) | Raw Materials, Medicinal & Genetic |
| Production water | Rivers & Lakes | Water Abundance, Clean Water |
| Waste processing | Inland Wetlands | Clean Water |
| Site environmental health | Multiple | Healthy Soils, Clean Air |
Nitto has commenced TNFD-aligned disclosure, integrating biodiversity considerations into environmental management.
Source: Nitto Denko Press Release
real estate: daiwa house reit
Real estate assets interface with ecosystems at the site level and through regional dependencies.
| Dependency | Stock | Flow |
|---|---|---|
| Site conditions | Urban Open Space, Coastal Systems | Risk Resilience, Climate Stability |
| Stormwater management | Inland Wetlands, Rivers & Lakes | Clean Water, Risk Resilience |
| Urban heat mitigation | Urban Open Space | Climate Stability |
| Tenant amenity | Urban Open Space | Recreation & Experiences, Aesthetic & Sensory |
Daiwa House REIT has implemented a detailed TNFD/LEAP process, linking nature-related analysis to asset management decisions and ESG-indexed fee structures.
Source: Daiwa House REIT TNFD Report
the ensurance framework
Ensurance operationalizes stocks and flows through dedicated agents — each representing a specific ecosystem stock or service flow.
stock agents
Each of the 15 ecosystem stocks has a corresponding .[ensurance](#concept:ensurance) agent:
| Agent | Represents |
|---|---|
| temperate-forests.ensurance | Temperate forest ecosystems globally |
| boreal-forests.ensurance | Boreal forest ecosystems |
| tropical-forests.ensurance | Tropical forest ecosystems |
| inland-wetlands.ensurance | Marsh, swamp, peatland ecosystems |
| rivers-lakes.ensurance | Freshwater systems |
| coastal-systems.ensurance | Coastal and estuarine ecosystems |
| grasslands.ensurance | Grassland and prairie ecosystems |
| shrublands.ensurance | Shrubland and scrub ecosystems |
| marine-systems.ensurance | Ocean and marine ecosystems |
| polar-alpine.ensurance | Polar and alpine ecosystems |
| deserts.ensurance | Arid and semi-arid ecosystems |
| subterranean.ensurance | Underground and aquifer systems |
| cultivated-developed.ensurance | Agricultural and developed lands |
| urban-open-space.ensurance | Urban green infrastructure |
| rural-open-space.ensurance | Rural buffer and transition zones |
flow agents
Each of the 19 ecosystem service flows has a corresponding .ensurance agent:
| Agent | Represents |
|---|---|
| water-abundance.ensurance | Freshwater provision services |
| climate-stability.ensurance | Climate regulation services |
| clean-water.ensurance | Water purification services |
| clean-air.ensurance | Air quality services |
| risk-resilience.ensurance | Natural disaster mitigation |
| pollination.ensurance | Pollination services |
| erosion-control.ensurance | Soil retention services |
| pest-disease-control.ensurance | Natural pest management |
| habitat.ensurance | Biodiversity support |
| raw-materials.ensurance | Material provisioning |
| food.ensurance | Food production support |
| energy.ensurance | Natural energy services |
| healthy-soils.ensurance | Soil health maintenance |
| medicinal-genetic.ensurance | Genetic and medicinal resources |
| recreation-experiences.ensurance | Recreation and tourism |
| research-learning.ensurance | Scientific and educational value |
| aesthetic-sensory.ensurance | Scenic and sensory value |
| art-inspiration.ensurance | Cultural and creative inspiration |
| existence-legacy.ensurance | Intrinsic and bequest value |
These agents have onchain accounts. Investment flows to them fund protection and restoration of the stocks and flows they represent.
from vocabulary to action
Mapping your dependencies to stocks and flows is the first step. The second is investing in the ecosystems you depend on.
the disclosure-investment gap
Most TNFD implementations stop at disclosure. Companies produce beautiful reports identifying their nature dependencies — then continue operating without investing in those ecosystems.
Disclosure without investment is documentation, not action.
what investment looks like
| Stage | Disclosure | Investment |
|---|---|---|
| Identify | "We depend on temperate forests for water" | Fund temperate-forests.ensurance |
| Quantify | "$50M annual value from water services" | Proportional ensurance premiums |
| Monitor | "Forest cover in our watershed declined 2%" | MRV-linked funding adjustments |
| Report | TNFD-aligned disclosure | Verifiable investment trail |
step-by-step: mapping your dependencies
step 1: list your material dependencies
What does your organization depend on from nature? Use ENCORE or similar tools to generate an initial list by sector.
step 2: classify by flow
For each dependency, identify which of the 19 ecosystem service flows it represents.
step 3: trace to stocks
For each flow, identify which ecosystem stocks provide it in your operating locations. This is where location mapping (see how to map nature-related locations) connects.
step 4: assess materiality
Rank dependencies by:
- Economic value to your operations
- Current condition of source ecosystems
- Trend direction (improving/degrading)
- Replaceability (can you substitute?)
step 5: connect to investment pathways
For each material dependency, identify how you could invest in the stocks and flows that provide it.
frequently asked questions
how do stocks and flows relate to ENCORE?
ENCORE maps sector dependencies to ecosystem services (flows). The stocks framework adds the question: which ecosystem types provide those services in your locations? Together they complete the picture.
what about impacts, not just dependencies?
The same framework applies. Your impacts affect specific stocks (e.g., land use change reduces temperate forest area) and flows (e.g., pollution degrades clean water services). Map impacts to stocks and flows for complete disclosure.
how specific should my disclosure be?
"We depend on ecosystem services" = F. "We depend on water abundance from temperate forests and inland wetlands in the Kanto region" = A.
can I invest in a specific stock or flow?
Yes. Each stock and flow has a corresponding .ensurance agent with an onchain account. You can fund specific ecosystem types or services based on your dependency profile.
next steps
To map where your dependencies are located: Read: how to map nature-related locations in japan for TNFD
To explore stocks and flows visually: Natural Capital stocks and flows
To see the exposure mapping: Sector-ecosystem dependencies
To discuss your dependency mapping: Contact BASIN