Andean grassland stability across spatial scales increases with camelid grazing intensity despite biotic homogenization
Data files
Feb 03, 2025 version files 17.79 KB
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Data4Dryad.xlsx
14.85 KB
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README.md
2.94 KB
Abstract
Intensive land use and changing environmental conditions are reshaping the biodiversity, functioning and stability of local Andean grassland communities. It remains unclear whether these effects propagate to larger spatial scales that are most relevant for policy and conservation. Using a multiscale framework, we quantified the influence of grazing intensity and environmental factors on the diversity and temporal stability of productivity in Andean grassland plant communities at both the local (within communities) and larger (among neighboring communities) spatial scales. We found that higher grazing intensity and soil total nitrogen were related to greater stability at both the local (alpha stability) and larger (gamma stability) scales. Higher gamma stability at higher grazing intensity resulted from enhanced spatial asynchrony of productivity among communities despite biotic homogenization. That is, while higher grazing intensity reduced compositional differences among communities (beta diversity) which in turn decreased spatial asynchrony, this indirect effect was not strong enough to counteract the direct positive influence of grazing on spatial asynchrony and gamma stability. Additionally, local diversity (alpha diversity) decreased with increasing soil acidification but did not influence alpha or gamma stability.
Synthesis: Our results emphasize the necessity of considering the complex influences of grazing intensity on diversity and stability at different spatial scales for the effective management of Andean grasslands.
README: Andean grassland stability across spatial scales increases with camelid grazing intensity despite biotic homogenization
https://doi.org/10.5061/dryad.3tx95x6s6
Description of the data and file structure
The dataset allows to investigate the relationship between community stability and biodiversity, exploring the scale-dependent impact of grazing on stability across a natural gradient of biodiversity, grazing intensity and abiotic factors within the tropical grasslands of the National Park Apolobamba in northwestern Bolivia.
Files and variables
File: MC_df.csv
Description:
Variables
- Site: Name of the seven selected study sites within the borders of the natural park Apolobamba.
- MC: Meta-community. We surveyed 105 plots across the seven study sites. Per site there are five meta-communities, each consisting of three replicated plots of 25-m2, within an area of 300 x 300 m.
- GI: Grazing intensity along a natural gradient. Grazing intensity (GI) was estimated by dung pile measurements along a transect of 100 m x 20 m within each meta-community, resulting in a total of 35 grazing intensity transects with 5 measurements per study site (Fig. S2). We assumed that the three plots within a meta- community have the same grazing intensity. Dung piles are accumulated over many years, thus providing an estimate of long-term grazing pressure. We defined the GI index as animal density (animal unit/ hectare): GI_index=n/a*t*d where n is the dung pile weight (in kg), a is the sampling area (in hectares), t is number of days the animals forage at each study site throughout the year, and d is the defecation rate per animal (0.446 kg/ day) (Pfeffer et al. 2018).
- TAP: Mean total annual precipitation in mm for the same period of ecosystem stability measurements (2015–2020)
- beta: Bray–Curtis dissimilarity among the three aggregated plots in the meta community, unitless
- Alt: Altitude asl in m
- MAT: Mean annual temperature in degree Celsius for the same period of ecosystem stability measurements (2015–2020)
- TN: Total soil nitrogen in kg. N/ha
- invsimp: Mean inverse Simpson per meta community, unitless
- eve: Mean evenness per meta community, unitless
- richness: Mean species richness per meta community (number of species per m2).
- Latitude: Latitude in degrees
- Longitude: Longitude in degrees
Code/software
Excel
Access information
Data was derived from the following sources:
- For MAT we collected data from the MODIS- MOD11A1 V6 product (Wan et al., 2015) in 1 km resolution. TAP was gathered in a high spatial resolution data from the Climate Hazards group Infrared Precipitation with Stations (CHIRPS) dataset (Funk et al., 2015) in 5 km resolution. The CHIRPS dataset provides infrared Cold Cloud Duration (CCD) satellite observations calibrated with in-situ station gauge data (Funk et al., 2015).