Holdridge Life Zones Classification in New Caledonia Habitats

Description

This dataset aims to represent, in geographic space, the distribution of life zones as first defined by Holdridge in 1947 and updated in 1967. Life zones are delineated through three parameters:

Mean Annual Biotemperature (°C): This axis represents the average annual temperature, considering only temperatures above 0°C, as it influences biological activity. It determines the thermal regime of the environment.

Annual Precipitation (mm): This axis measures the total annual precipitation, indicating moisture availability. It is crucial for determining the hydric regime and supporting different types of vegetation and ecosystems.

Potential Evapotranspiration Ratio (PET): This axis is the ratio of potential evapotranspiration to annual precipitation. It reflects the balance between water demand and supply, indicating aridity or humidity levels and influencing vegetation types and ecosystem dynamics.

We used a combination of WorldClim datasets (Biotemperature and potential evapotranspiration) and Météo-France Aurelhy datasets (Annual Precipitation) specifically designed for New Caledonia to produce the raster with a 1 km² resolution.

Content

This dataset was produced, analyzed, and verified using a combination of open-source software, including QGIS, PostgreSQL, PostGIS, Python, R and the GDAL library, all running on Linux.

amap_raster_holdridge_nc.tif is a GeoTIFF, utilizing the WGS84 international coordinate system, and consists of a single band with three major classes coded as

Dry life zone (rast = 1)

Moist life zone (rast = 2)

Rain life zone (rast = 3)

holdridge_3classes_NC.png is an image illustrating the valid domain of life zones in New Caledonia and the classification used in the dataset.

Limitations

Strictly, the classification leads to five distinct classes (very dry, dry, moist, wet, and rain), but as the two extreme classes cover less than 0.5% of New Caledonia, we merged very dry and dry into the "dry" class, as well as wet and rain into the "rain" class as illustrated in the Figure holdridge_3classes_NC.png.