Colombia's bioregions as a source of useful plants

Abstract

The aim of our study was to assess the importance of different Colombian bioregions in terms of the supply of useful plant species and the quality of the available distribution data. We assembled a dataset of georeferenced collection localities of all vascular plants of Colombia available from global and local online databases. We then assembled a list of species, subspecies and varieties of Colombia's useful plants and retrieved all point locality information associated with these taxa. We overlaid both datasets with a map of Colombia's bioregions to retrieve all species and useful species distribution records in each bioregion. To assess the reliability of our estimates of species numbers, we identified information gaps, in geographic and environmental space, by estimating their completeness and coverage. Our results confirmed that Colombia's third largest bioregion, the Andean moist forest followed by the Amazon, Pacific, Llanos and Caribbean moist forests contained the largest numbers of useful plant species. Medicinal use was the most common useful attribute across all bioregions, followed by Materials, Environmental uses, and Human Food. In all bioregions, except for the Andean páramo, the proportion of well-surveyed 10×10 km grid cells (with ≥ 25 observation records of useful plants) was below 50% of the total number of surveyed cells. Poor survey coverage was observed in the three dry bioregions: Caribbean deserts and xeric shrublands, and Llanos and Caribbean dry forests. This suggests that additional primary data is needed. We document knowledge gaps that will hinder the incorporation of useful plants into Colombia's stated plans for a bioeconomy and their sustainable management. In particular, future research should focus on the generation of additional primary data on the distribution of useful plants in the Amazon and Llanos (Orinoquia) regions where both survey completeness and coverage appeared to be less adequate compared with other regions.

Fig 1. Number of records of all vascular plants and useful species in bioregions.

(A) Bioregion map of Colombia. (B) Number of records of all vascular plants (log-transformed) vs the mean vascular species richness (average of the number of all vascular plant species found in each grid cell of 10 x 10 km) for each bioregion. (C) Number of records of useful plants (log-transformed) vs mean useful species richness (average number of useful species found in each grid cell of 10 x 10km. In (B) and (C), points at the top right of the plot represent bioregions with greater numbers of records, but also with higher numbers of species after accounting for area, because mean species richness (species/cells ratio) represents the average number of species per unit area (in this case, 10×10 km grid cell).

Fig 2

Mean species richness in the study area and in the surveyed areas: all vascular plants (A) and useful plants (B). Mean species richness in the study area was estimated as the number of species recorded in each 10 x 10 km grid cell within the geographic extent of Colombia; surveyed area richness was estimated within all 10 x 10 km grid cells with at least 1 record, and well surveyed area richness was estimated within all 10 x 10 km grid cells with ≥ 25 records. See Fig 1 for bioregion names and S2.5 and S2.6 Tables in S2 File, for richness values.

Fig 3. Records of useful plants per category of use.

(A) Number of records of useful plants (log-transformed) vs the ratio of number of useful species per cell (species/cells ratio) for each category of use. (B) Number of records of useful plants (log-transformed) per category of use (axis x) and ecosystem (y axis). Dendrograms show clusters based on the number of records.

Fig 4

Survey completeness for all vascular (A) and useful (B) plants by bioregion. Percentage of 10×10 km well surveyed grid cells, defined as those with ≥ 25 observations, is calculated by bioregion.