Want to know where (most) trees grow? Ask TreeGOER

A woman holds an acacia tree seedling at a plantation in Yangambi, DRC. Photo by Axel Fassio/CIFOR-ICRAF

A new open-access database that documents the observed environmental ranges for most known tree species is tipped to be a key development in climate change adaptation and restoration planning.

The Center for International Forestry Research and World Agroforestry (CIFOR-ICRAF) has just released the Tree Globally Observed Environmental Ranges database (TreeGOER), which documents the ranges of 51 environmental variables for the observed occurrences of 48,129 tree species. The database, which was published in open repository Zenodo and described in a new article in Global Change Biology, allows users to explore the impact of climate change on tree species and better target tree planting to support restoration and climate change adaptation.

“TreeGOER will support climate change adaptation and is a useful tool for studying tree biogeography,” said Roeland Kindt, a senior ecologist at CIFOR-ICRAF, who created the database and wrote the accompanying article. “For instance, it shows that climate change is particularly likely to tend to reduce tree species richness in South America, meaning interventions there to support tree diversity may be particularly important.”

Change in predicted number of suitable tree species using TreeGOER environmental data comparing a historical baseline with the predicted future climate for the 2050s to generate a ‘Future Species Proportion’ map. The shown analysis, for 2,000 locations, focuses only on areas where the average monthly temperature was above 10^OC year-round and also excludes arid and hyper-arid regions. Future climate data were for shared socio-economic pathway 3-7.0 (a higher emissions scenario). Animation by Roeland Kindt/CIFOR-ICRAF.

Change in predicted number of suitable tree species (scaled as log₁₀(suitable species+1)) using TreeGOER environmental data comparing a historical baseline with the predicted future climate for the 2050s by climate moisture index, for 2,000 locations (as in previous animation) aggregated into longitude zones (“West”, “Central” and “East”) globally. The thick blue lines represent smoothed regression curves. Thin blue lines show the direction of movement between baseline and future climates and do not represent modelled richness at intermediate time intervals. The animation shows especially the predicted loss of species richness in the 2050s compared to the baseline in moist Equatorial latitudes in the “West” zone, which includes the Amazon region. Animation by Roeland Kindt/CIFOR-ICRAF

TreeGOER is expected to become a crucial resource for land managers and researchers in understanding how climate change could affect where tree species grow and thrive in the future. Using the database, they can make plans that support climate change adaptation, such as by planting climate-adapted tree species mixtures, and by encouraging local adaptation and facilitated migration of natural tree stands that will support healthy future forests and agroforestry systems.

The database complements another recently-created CIFOR-ICRAF resource called the GlobalUsefulNativeTrees database (GlobUNT), which documents the uses of 14,014 tree species for ten different use groups to support synergies between biodiversity recovery and local livelihoods in landscape restoration. “Taken together, TreeGOER and GlobUNT will support land managers in directing climate change adaption and restoration interventions toward the planting of native tree species, which is an aim of many restoration programmes,” said Kindt.

“TreeGOER and GlobUNT complement a wider suite of resources developed by CIFOR-ICRAF that assist selection of ‘the right tree for the right place and the right purpose’, which is available from the Global Tree Knowledge Platform”, said Ian Dawson, another senior scientist at CIFOR-ICRAF, who with Roeland Kindt and other colleagues has been involved in the platform’s development.

Subcontinental native tree species richness for ten tree uses as documented by the GlobUNT database. The ten use categories are: Animal Food, Environmental Uses, Fuel, Gene Sources, Human Food, Invertebrate Food, Materials, Medicines, Poisons and Social Uses. The maps show that relative species richness varies across use groups for particular locations, which may be an important factor in determining which tree species to plant to support livelihoods that will in turn support tree establishment and restoration success for native tree species. Animation by Roeland Kindt/CIFOR-ICRAF

Acknowledgements

TreeGOER was developed through funding provided by the Darwin Initiative, Norway’s International Climate and Forest Initiative, and the Green Climate Fund.