Detection of long-term landscape changes and trajectories in a Pannonian sand region: comparing land-cover and habitat-based approaches at two spatial scales

Abstract

A key driver of biodiversity loss is human landscape transformation. Change detection and trajectory analysis are frequently applied methods for studying landscape change. We studied to what degree habitatspecific change detection and trajectory analysis provide different information on landscape change compared to the analysis with land-cover statistics. Our research was carried out at two spatial scales (regional, 1800 km 2 , 360 random points; local, 23 km 2 , polygon-based maps) in the Kiskunság, Hungary. Spatio-temporal databases were prepared using historical maps, aerial photos and satellite images from 1783, 1883, 1954, and 2009. Local expert knowledge of landscape history and recent vegetation was used during the historical reconstructions.We found large differences at both scales between land-cover based and habitat-specific analyses. Habitatspecific change detection revealed that grassland loss was not continuous in the different habitats, as land-cover based analysis implied. Ploughing affected open sand grasslands and sand steppes differently in different periods. It was only apparent from the habitat-specific analyses that from the grasslands only mesotrophic and Molinia meadows were relatively constant, up until the 1950s. The gradual increase in forest area revealed by land-cover CHD analyses was split into natural and anthropogenic processes by habitat-specific analyses. Habitat specific trajectory analysis also revealed ecologically important historical differences between habitats. Afforestation affected especially the open sand grasslands, whereas wetland habitats were relatively stable. The most important trajectory was the one in which closed sand steppes were ploughed during the 19 th century, and remained arable fields until present. Fifty percent of the regional trajectories of 18 th century open sand grasslands terminated in tree plantations at present, though 82% of the current open sand grasslands of the local site can be regarded as ancient.We concluded that dividing land-cover categories into finer habitat categories offered an opportunity for a more precise historical analysis of key habitats, and could reveal important ecological processes that cannot be reconstructed with land-cover based analyses. It also highlighted habitat-specific processes making natural and social drivers better interpretable. Information on the diversity of habitat-histories may serve as a basis for spatially more explicit conservation management.

Changes in forest cover in Sudety Mountains during the last 250 years: patterns, drivers, and landscape-scale implications for nature conservation

“…The size of the squares was adjusted to the acreage and shape of the study area, and to the size used for landscape scale-studies in Central Europe [63,64]. For 25 squares placed within the study area (Fig.…”

Use of long‐term data to evaluate loss and endangerment status of Natura 2000 habitats and effects of protected areas

“…These trends were due to a change from cattle to sheep grazing in the case of juniper‐poplar forest steppe thickets on sand during the 19th century (Biró et al. ); the abandonment of agriculture in flood ways in the case of soft‐wood alluvial forests (De Keersmaeker et al. ); and the decrease of livestock density on pastures in the case of reed beds.…”

“…Wet alluvial meadows were converted only after the countrywide program of river regulation, and Pannonic salt habitats were converted after WWII. Molinia meadows were drained even later because they occurred in smaller, closed depressions that were harder to drain (Biró et al 2013). Considering the high uncertainty of estimation, we categorized this habitat as having a delayed trend.…”

Assessing the potential supply of landscape services to support ecological restoration of degraded landscapes: A case study in the Austrian-Hungarian trans-boundary region of Lake Neusiedl

“…When addressing the issue on landscape's potential, it is very much driven by the reference scale which needs to be set. One way would be to look at former time points and compare land use systems and related land consumption (Biró et al, 2013;Frondoni et al, 2011;Prinz et al, 2010). This implies that former land use was oriented at the potential of the landscapes (Biró et al, 2013;Frondoni et al, 2011).…”

“…One way would be to look at former time points and compare land use systems and related land consumption (Biró et al, 2013;Frondoni et al, 2011;Prinz et al, 2010). This implies that former land use was oriented at the potential of the landscapes (Biró et al, 2013;Frondoni et al, 2011). As natural systems, whose components are the result of natural selection, are supposed to be ecologically sustainable (Ewel, 1999), we choose another way by excluding land use at all and try to derive the potential of the landscape regardless of any human activity.…”