Operation

About

Moving carbons stocks between Pools is defined as an Operation.

Operations are meant to reflect,

1. Ongoing natural processes, such as growth, specific events, natural/human induced
2. Plant material to products & debris pools, wildfire moves plant material to debris and atmosphere pools

Terms Introduced In This Section

The below terms are introduced in this section (Operations),

1. Flux (Fluxes)
2. Flux Values
3. Flux Table
4. Growth Flux

Flux

In an Operation, the amount of stock moved during an operation is referred to as an flux - allowing Operations to make it feasible for FLINT to track changes in carbon stock through time, including Fluxes into and out of pools.

Operations & FLINT

FLINT uses operations to update values for Simulation Units, and to record Flux Values into a Flux Table.

For example, an operation reflecting plant growth can be applied to above-ground biomass pools to estimate the Growth Flux.

Transferring carbon stock from one pool to another, ensuring the system is balanced, such that the sum of the fluxes is equal to the sum of the stock changes.

FLINT will report if the system is not balanced, taking actions (flagging, tracking). Depending on which pools the flux relates, it is classified differently in the flux table, and the resulting carbon stock tables.

The resulting information can then be used to calculate different characteristics of the Simulation Unit. As an example, summing all stock change in the above-ground, below-ground biomass and net litter turnover, the Net Primary Production (NPP) can be calculated.

Module

About

A self-contained set of operations, determining the state, or change in, variables across a specified period of time for a single Simulation Unit in direct response to event notifications from the FLINT core system (Unit Controller).

Terms Introduced In This Section

The below terms are introduced in this section (Module),

1. Unit Controller

Module Operation

Each module contains state variables, details to update states. These state variables can be climate data, or information about disturbances to simulate.

Each module performs calculations, returns information about the updates to apply to each of the state variables and Carbon pools.

Module-specific metadata about units and time-step size is required, and is stored in the Unit Controller along with the carbon pools, fluxes, operations, source pool.

Types of Modules

There are two types,

1. Internal
2. External

It is so to encourage high flexibility, with new modules being 'plugged in' as they are developed.

Internal Modules

They tend to be generic utility modules, for example, for producing output tables

External Modules

They are regionally or nationally specific.

Standard Modules

FLINT provides 6 standard modules for simulating changes in forest and crop systems, including changes in soil carbon. They run at a monthly step interval, and include,

1. "Empirical Forest Growth" Module (EFGM)
2. "Hybrid Forest Growth" Module (HFGM)
3. "WOFOST Crop Growth" Module (WCGM)
4. "Turnover" Module (TM)
5. "Decomposition" Module (DM)
6. "RothC Soil Carbon" Module (RSCM)

Modules For Disturbance Events

Disturbance Events occur intermittently, and affect carbon stocks. They include,

1. Natural Events
2. Anthropogenic Events

Some examples include fire, harvesting, ploughing, fertilizer application. While disturbance events are modules within FLINT, they are referred to separately as they are not run on every simulation as are the aforementioned modules.

This information can be used to attribute the disturbance event to Simulation Units using a pre-determined criteria (e.g. randomly, weighted, or based on a unit characteristic).

Carbon Pool Events are those that directly affect one or more carbon pool, while non-carbon pool events indirectly affect one or more non-carbon pool.

Carbon Pool Events

• Fire
• Harvest
• Herbicide
• Plough
• Debris Mulching
• Grazing
• Organic Matter Additions
• Planting

Non-Carbon Events

• Irrigation
• Fertilizer Application
• Compaction

References

Read more about Operations and Modules on Moja Global's Wiki!