The contribution of landscape features, climate and topography in shaping taxonomical and functional diversity of avian communities in a heterogeneous Alpine region

Landscape scale effects of primary productivity on forest bird species occurrence and abundance in Argentina

Context

Approaches estimating landscape effects on biodiversity frequently focus on a single extent, finding one 'optimal' extent, or use narrow extents. However, species perceive the environment in different ways, select habitat hierarchically, and respond to multiple selection pressures at extents that best predict each pressure.

Objective

We aimed to assess multi-scale relationships between primary productivity and species occurrences and abundances.

Methods

We used a multi-scale approach, called 'scalograms', to assess landscape level effects of primary productivity, in the form of Dynamic Habitat Indices (DHIs) on the occurrences and abundances of 100 Argentinian forest bird species. We used average DHI values within multiple extents (3 × 3 to 101 × 101 pixels; 30 m resolution), and 11 'scalogram' metrics as environmental inputs in occurrence and abundance models.

Results

Average cumulative DHI values in extents 81 × 81 to 101 × 101 pixels (5.9 - 9.2 km2) and maximum cumulative DHI across extents were in the top three predictors of species occurrences (included in models for 41% and 18% of species, respectively). Average cumulative DHI values in various extents contributed ~ 1.6 times more predictive power to occurrence models than expected. For species abundances, average DHI values and scalogram measures were in the top three predictors for < 2% of species and contributed less model predictive power than expected, regardless of DHI type (cumulative, minimum, variation).

Conclusions

Argentinian forest bird occurrences, but not abundances, respond to high levels of primary productivity at multiple, broad extents rather than a single 'optimal' extent. Factors other than primary productivity appear to be more important for predicting abundance.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10980-025-02081-5.

Spatiotemporal patterns and drivers of orchard meadow loss in South Tyrol, Italy

Orchard meadows, a specific agroforestry system characterised by scattered high-stem fruit trees, are a traditional element of several cultural landscapes in Central Europe and provide important ecosystem services. Since the middle of the 20th century, orchard meadows have drastically declined across Europe. Spatial information on the drivers and patterns of such a decline in several regions in Central Europe is lacking. In this study, we aimed to provide the first detailed insights into the development of orchard meadows in South Tyrol. We assessed the current distribution of orchard meadows in South Tyrol (Northern Italy) and analysed the patterns and drivers of their decline over the last 75 years. Aerial images of the orchard meadows in South Tyrol from the 1950s up to the 2020s were examined, and changes in their distribution were statistically analysed. The results revealed that the historical orchard meadow area in South Tyrol has decreased by more than 6,000 ha (-95%) over the past 75 years, showing one of the largest reductions in Central Europe. Orchard meadow loss was highest at lower elevations (-5,155 ha), shallow slopes (-4,313 ha), and expositions towards the south (-5,035 ha). Orchard meadows have declined due to agricultural intensification towards the establishment of modern fruit orchards (56%) and intensively managed grasslands (8%), urbanisation (23%), and reforestation (6%), and other types of land use/land cover (6.5%). Only 0.5% of the traditional orchard meadows have been preserved. The results suggest that orchard meadows are at a high risk of disappearing from the South Tyrolean landscape, resulting in the loss of genetic diversity of many local or indigenous fruit varieties (especially apples and pears). Immediate action is needed to safeguard the current orchard meadow population and appropriate management measures are needed to highlight the multiple values of orchard meadows and provide a valuable alternative to intensive arable farming.