Aboveground Biomass Along an Elevation Gradient in an Evergreen Andean–Amazonian Forest in Ecuador

Abstract

The aim of this research was to assess how aboveground biomass (AGB) changes along an altitudinal gradient in evergreen Andean–Amazonian forests [Evergreen Lower Montane Forest, northeastern Cordillera of the Andes; Evergreen Piedmont Forest (EPF), northeastern Cordillera of the Andes; and Evergreen Lowland Forest (ELF), Napo–Curaray] from 373 to 1,826 m above sea level (m.a.s.l.). All trees measured in nine permanent 0.36-ha plots (60 × 60 m) were ≥ 10-cm (diameter at breast height) in the aforementioned ecosystems. We assessed tree density, basal area, species richness, and AGB. In the tree inventory, we measured 2,132 trees (Lower Montane Forest 687, Piedmont Forest 773, and Lowland Forest 672). AGB (Mg ha–1) increases with decreasing elevations: 310.26 ± 81.59 (SD) for the Evergreen Lower Montane Forest, 347.73 ± 90.38 (SD) for the EPF, and 377.39 ± 42.73 (SD) for the ELF. Otoba glycycarpa and Alchornea latifolia were the species with the highest biomass importance value (BIV) in the Evergreen Lower Montane Forest (1,421–1,826 m.a.s.l.), Spirotheca rosea and Pouteria glomerata in the EPF (892–1,195 m.a.s.l.), and Otoba glycycarpa and Iriartea deltoidea in ELF (373–394 m.a.s.l.). Biomass contribution along the altitudinal gradient in the evergreen Andean–Amazonian forests is concentrated in few species. This has implications in forest management and reforestation programs where the main focus is on carbon sequestration.

Changes in Relationship between Forest Biomass Productivity and Biodiversity of Different Type Subtropical Forests in Southern China

“…Our results demonstrated that there were differences in the ABP, BBP, and TP of woody plants at various altitude gradients, underscoring the important impacts of climate and environmental gradients associated with varying altitudes on forest productivity [64]. Specifically, our results are consistent with previous studies finding that ABP and TP tend to be the highest in low-altitude areas and lowest in high-altitude sites [65]. Warmer temperatures and low altitude probably provide favorable conditions for plants, which leads to increases in aboveground and total productivity [66].…”

Climate and soil stressed elevation patterns of plant species to determine the aboveground biomass distributions in a valley-type Savanna

“…Furthermore, it is imperative to underscore that both altitudinal (as discerned in Section 3.2 of this study) and latitudinal (as documented by Wang ( Wang et al., 2022 )) biomass patterns within the arid valley consistently evince a decremented trend in litter biomass with ascending altitude or latitude. This is significantly different from the pattern of an overall decrease in aboveground biomass of herbaceous swamp vegetation on the Qinghai Tibet Plateau with increasing altitude ( Shen et al., 2021 ), and consistent with the pattern of an Evergreen Andean–Amazonian Forest in Ecuador ( Maza et al., 2022 ). Along the altitudinal gradient, the nadir of litter biomass within the riverine savanna community is concentrated within the elevation range of 1500-1700 meters, emblematic of the upper demarcation of this valley’s savanna vegetation (as expounded upon in Section 3.1 of this study).…”

Similar Turnover Rates Between Pteridophytes and Angiosperms Trees Along the Northern Ecuador Andean Foothills

“…Pteridophytes and trees are distant related plant clades, but the similar turnover patterns suggest that environmental filters may have actuated in the assembly of both communities. Both groups responded in a similar manner to differences in elevation, with their dissimilarity increasing as the distance between plots increases, a pattern that follows the decrease in species richness from mid-to low-elevations in the study area (Riaño & Moulatlet 2022, Maza et al 2022. Indeed, the regional species richness can largely influence turnover patterns along elevational gradients in the Andes (Olivares & Kessler 2020), but dissimilarity changes with increasing distance could also be related to the changes in the environmental conditions (such as local climate and soils) in such heterogenous landscape (Tuomisto et al 2003, Moulatlet et al 2019.…”

“…Unknown species were identified at the genus level. A complete description of tree diversity in the area has been reported by Maza et al (2022).…”