Native forest metacommunity structures in Uruguay shaped by novel land‐use types in their surroundings

Abstract

We explore the effect of land‐use change from extensively used grasslands to intensified silvi‐ and agricultural monocultures on metacommunity structure of native forests in Uruguay. We integrated methods from metacommunity studies, remote sensing, and landscape ecology to explore how woody species distribution was influenced by land‐use change from local to regional scale. We recorded richness and composition of adult and juvenile woody species from 32 native forests, created land‐use maps from satellite image to calculate spatial metrics at landscape, class, and patch levels. We also analyzed the influence of land use pattern, climate, topography, and geographic distance between sites (d) on metacommunity, and created maps to visualize species richness and (dis)similarity between communities across the country. Woody species communities were distributed in a discrete pattern across Uruguay. Precipitation and temperature seasonality shaped species distribution pattern. Species richness and community dissimilarity increased from West to East. Latitude did not influence these patterns. Number of patches, landscape complexity, and interspersion and juxtaposition indexes determine woody species distribution at landscape level. Increasing areas covered by crops and timber plantation reduced species richness and increased community dissimilarity. The spatial metrics of native forest fragments at patch level did not influence metacommunity structure, species richness, and community dissimilarity. In conclusion, Uruguayan native forests display a high range of dissimilarity. Pressure of neighborhood land uses was the predominant factor for species assemblages. Conserving landscape structures that assure connectivity within and among native forest patches is crucial. On sites with rare target species, the creation of alliances between governmental institution and landowner complemented by incentives for biodiversity conservation provides opportunities to advance in species protection focused on those less tolerant to land‐use change.

Quo vadis Patria Gaucha? Uruguayan pathways of land use change

“…Our data demonstrate that agroindustrial intensification in rural Uruguay occurs mainly at the expense of natural grasslands (Figures 5D-F, J-L). Intensification consists of extension of agro-industrial crops and timber plantations (Ramírez and Säumel, 2022a), increasing stocking rates, the implementation of artificial or improved pastures to foster grassland productivity and an increasing use of annual forage crops (Figure 4B). This process is expected to result in significant discharges of agrochemical pollutants into local freshwaters (Ramirez and Säumel, 2023) as well as in the gradual disappearance of natural grasslands (Modernel et al, 2016).…”

A step to disentangle diversity patterns in Uruguayan grasslands: Climatic seasonality, novel land‐uses, and landscape context drive diversity of ground flora

“…In the transition from the forest edge to the open grassland, numerous factors (e.g., elevation, soil, tree density, flooding frequency, or climate) determine the grassland community structure (Bernardi et al, 2016). In contrast to crops, native forests and timber plantations function as barriers within the landscape and disrupt important ecosystem processes such as seed dispersal and pollination, for example, by wind in an originally almost forestless landscape (Ramírez & Säumel, 2022b; Ramos et al, 2020), while the park forests as a transition zone between native riparian forests and open grasslands can support zoochory (Manning et al, 2006; Pozo & Säumel, 2022).…”

“…We used Landsat 5 when Landsat 8 had a cloud cover percentage over 10%. For this, images were first atmospherically and geographically corrected using the land surface method (Moran et al, 1992) and dark object saturation (Chavez Jr, 1996) in Matlab (The Mathworks Inc., Natick, MA; for details see Ramírez & Säumel, 2022b). The resulting raster images have a spatial resolution of 30 m, and reveal different land covers, including timber plantations, native forest, grassland, and cropland (see detail in Ramírez & Säumel, 2022b).…”

Landscape, agrobiodiversity, and local knowledge in the protected area “Quebrada de los Cuervos y Sierras del Yerbal,” Uruguay

“…Some of these species also emerge in cultivated spaces, being tolerated and protected. Most of these species are trees, predominantly exhibiting zoochory syndromes (Ramírez and Säumel, 2022). On the other hand, the herbaceous plants, mainly from the Asteraceae family, exhibit anemochory syndromes, while only a few species show autochory syndromes.…”