Biome-scale ecosystem dynamics modelling using LPJ-GUESS
The project aimed to analyze ecosystem responses to IPCC scenarios, using the LPJ-GUESS model.
The Atlantic Rainforest in SSP2-4.5 and SSP5-8.5 IPCC (2021) scenarios were analyzed, from 2000 to 2100. The table shows the changing in parameters according to each scenario.
How the biome might be affected by future changes
By changing the parameters, both scenarios showed an increase in Leaf Area Index (LAI), as well as Gross Primary Production (GPP), and Net Primary Production (NPP). i.e. the plants will uptake more carbon from the atmosphere (NEE C flux), leading to an increase in LAI and, consequently, in the biomass.
In the SSP2-4.5 scenario analyzed, the Plant Functional Types (PFTs) showed a change over the years.
The temperate broadleaved evergreen tree (TeBE) will reduce while tropical types such as TrBE (tropical broadleaved evergreen tree), and TrIBE (tropical broadleaved evergreen shade-intolerant tree) will show up.
The environmental factors responsible for most of the change
In the SSP5-8.5 scenario, CO₂ and temperature are the main factors responsible for Atlantic Rainforest biome changes.
The increase in CO₂ and temperature cause changes in PFTs, leading to a boost in LAI and NPP.
Glossary
LPJ-GUESS
It is a Dynamic Global Vegetation Model (DGVM) developed at Lund University, Sweden.
GPP
Gross primary production, the annually-accrued photosynthesis of an ecosystem.
NPP
Net primary production, the balance between GPP and annually-accrued autotrophic (plant) respiration. It corresponds to the amount of carbon available to plants each year for allocation to new biomass.
NEE
Net ecosystem exchange [of carbon]. In LPJ-Guess represents the balance between NPP, annually-accrued heterotrophic respiration, and carbon emissions due to wildfire disturbance.
LAI
Leaf area index, projective leaf (or needle) area divided by the area of ground covered.
PFTs
A set of functional and structural characteristics pertaining to some subset of the vegetation simulated at a particular location. A single PFT may represent from one up to a large number of species with relatively similar growth form, phenology, physiology, allometry, bioclimatic affinity, and life history.
TeBE
The plant functional type temperate broadleaved evergreen tree.
TrBE
The plant functional type tropical broadleaved evergreen tree.
TrIBE
The plant functional type tropical broadleaved evergreen shade-intolerant tree.
TrBR
The plant functional type tropical broadleaved raingreen tree.
C3G
The plant functional type cool (C3) grass.
C4G
The plant functional type warm (C4) grass.
The information above was taken from LPJ-Guess User's Guide.
