•Coppice harbours important biodiversity and has high cultural value.•Active coppice was quantified across Germany with remote sensing and literature.•Coppice declined by 99% between 1927 and 2020, ...less than 12,000 ha remain.•A single hotspot of 2000 ha is still managed as intact socio-ecological system.•The future of coppice depends on energy polices, firewood is an important product.
Coppicing is an ancient form of forest and woodland management. Coppice harbours important biodiversity and has a high cultural value, but has been transformed into high forest, neglected and abandoned over vast areas of Central Europe during the past century. Hotspots of remaining, active coppice systems are often under the radar of national and international forest and conservation authorities, because they are managed as socio-ecological systems by close-knit village communities. A better spatial overview of active and neglected coppice, and a quantification of trends in coppice management are important to allocate restoration and conservation priorities and identify potential areas for future coppice restoration.
I quantified trends in coppice area across Germany, a country with a historically large proportion of coppice, over the past century. I studied temporal and spatial patterns in management and transformation in a remaining hotspot of coppice without standards (‘simple coppice’) harnessing the Landsat archive and very high resolution, publicly available satellite images. I supplemented the remote sensing analysis by a review of published and unpublished, grey literature.
Across Germany, the area of active coppice with standards declined by 98.7% between 1927 and 2020, from ca. 400,000 ha to ca. 5,000 ha. The area of simple coppice declined from an estimated 680,000 ha to ca. 6,400 ha in the same period, i.e. by 99.1%. The area of overage (>35 years uncut) and abandoned coppice is difficult to define and quantify, but it likely exceeds 100,000 ha across Germany. Active coppice, dominated by oak (Quercus spp.) and birch (Betula spp.), is now found only in three regions. However, only in the federal state of Hesse, intact coppice landscapes have survived, comprising an area of ca. 2,000 ha. Here, traditional coppice management with relatively short rotation cycles and large coupes is maintained, with a stable area cut annually since 1986 and no coppice transformation to high forest since the 1970s. There was statistical evidence that the heating oil price influences the area that was cut annually, suggesting some potential for coppice restoration in the coming years, given rising energy prices.
As a conclusion, intact coppice systems have virtually disappeared in Germany, and with them their unique biodiversity and cultural heritage. There is an urgent need to safeguard the remaining socio-ecological systems, to develop incentives to maintain current active coppice and to develop integrative approaches to restore abandoned coppice, as a small-scale alternative to commercial forestry and close-to-nature silviculture.
The Palaearctic steppes range from the Mediterranean basin towards China, forming one of the largest continuous terrestrial biomes. The literature on steppe ecology and conservation is vast but ...scattered and often not available in English. We provide a review of some key topics based on a new definition of steppes, which includes also Mediterranean steppes and alpine rangelands of the Asian Highlands. Revisiting the terrestrial ecoregions of the world, we estimate that the Palaearctic steppe biome extends over ca. 10.5 million km
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. Major chorological regions differ in their macroclimatic niche with a clear distinction between Middle Asia with its winter precipitation and the Central Asian summer-rain regions of the Mongolian plateau and of Tibet. Steppe soils store large amounts of carbon, yet the sequestration potential is debated and depends on land use. Major physiognomic-ecological steppe types include forest-, typical-, desert-, and alpine-steppe, which vary in the importance of grasses, mainly C3 species. The steppes host a specialised fauna, and Middle Asia, Tibet, and especially Mongolia, have large herds of migrating ungulates. The share of pristine and protected sites is low in the steppe regions, with conversion into croplands being the most important land use impact in Europe, Middle Asia, and the Mediterranean, while grazing has a severe impact in some parts of Mongolia and Tibet. There are major gaps in our knowledge on: (1) the effects of climate change on the crucial seasonal patterns; (2) the role of steppe soils in the global carbon budget; and (3) the ecology and distribution of most animal groups except vertebrates.
Aim Long-term monitoring of biodiversity is necessary to identify population declines and to develop conservation management. Because long-term monitoring is labour-intensive, resources to implement ...robust monitoring programmes are lacking in many countries. The increasing availability of citizen science data in online public databases can potentially fill gaps in structured monitoring programmes, but only if trends estimated from unstructured citizen science data match those estimated from structured monitoring programmes. We therefore aimed to assess the correlation between trends estimated from structured and unstructured data. Location Denmark. Methods We compared population trends for 103 bird species estimated over 28 years from a structured monitoring programme and from unstructured citizen science data to assess whether trends estimated from the two data sources were correlated. Results Trends estimated from the two data sources were generally positively correlated, but less than half the population declines identified from the structured monitoring data were recovered from the unstructured citizen science data. The mismatch persisted when we reduced the structured monitoring data from count data to occurrence data to mimic the information content of unstructured citizen science data and when we filtered the unstructured data to reduce the number of incomplete lists reported. Mismatching trends were especially prevalent for the most common species. Worryingly, more than half the species showing significant declines in the structured monitoring showed significant positive trends in the citizen science data. Main conclusions We caution that unstructured citizen science databases cannot replace structured monitoring data because the former are less sensitive to population changes. Thus, unstructured data may not fulfil one of the most critical functions of structured monitoring programmes, namely to act as an early warning system that detects population declines.
Intensively managed viticulture dominates vast landscapes in the Mediterranean, but considerable vineyard abandonment has been observed over the past two decades. The effect of vineyard abandonment ...on biodiversity is poorly understood, making it difficult to assess the restoration potential of this common land-use change.
We assessed biodiversity responses to vineyard abandonment in Vaucluse, Southern France, using birds as indicator group. We compared bird abundance and diversity in a sample of 64 vineyards, pairing 16 currently managed vineyards with 16 recently abandoned and 16 managed with 16 longer abandoned vineyards. We used mixed models and multivariate techniques to establish relationships between bird diversity and structural attributes of the habitats, and we derived management-specific population densities in a distance sampling approach.
Long-abandoned vineyards hosted three times more species and showed a 3.6 times higher total bird abundance than managed viticulture. More recently abandoned vineyards had intermediate species numbers and abundance. Species richness patterns were not modulated by landscape composition and configuration, but higher abundances were found in landscapes with intermediate size of land-cover patches (i.e. field size). In managed vineyards, bird abundances were extremely low, with the exception of Woodlark Lullula arborea, which reached its highest abundance in managed vineyards. The bird community on abandoned vineyards shifted towards forest and woodland shrub species, likely driven by secondary succession, namely shrub encroachment and tree establishment.
The strongly positive effects of land abandonment might be due to the fact that only single vineyards (not entire landscapes) were abandoned, thereby increasing habitat heterogeneity at the landscape scale. The future state of the old abandoned vineyards is difficult to predict. As of yet, the abandoned vineyards support a comparably diverse community of breeding birds that reach high abundances in comparison to managed vineyards, within an otherwise impoverished agricultural landscape.
A large proportion of European biodiversity today depends on habitat provided by low-intensity farming practices, yet this resource is declining as European agriculture intensifies. Within the ...European Union, particularly the central and eastern new member states have retained relatively large areas of species-rich farmland, but despite increased investment in nature conservation here in recent years, farmland biodiversity trends appear to be worsening. Although the high biodiversity value of Central and Eastern European farmland has long been reported, the amount of research in the international literature focused on farmland biodiversity in this region remains comparatively tiny, and measures within the EU Common Agricultural Policy are relatively poorly adapted to support it. In this opinion study, we argue that, 10 years after the accession of the first eastern EU new member states, the continued under-representation of the low-intensity farmland in Central and Eastern Europe in the international literature and EU policy is impeding the development of sound, evidence-based conservation interventions. The biodiversity benefits for Europe of existing low-intensity farmland, particularly in the central and eastern states, should be harnessed before they are lost. Instead of waiting for species-rich farmland to further decline, targeted research and monitoring to create locally appropriate conservation strategies for these habitats is needed now.
Persecution and overexploitation by humans are major causes of species extinctions. Rare species, often confined to small geographic ranges, are usually at highest risk, whereas extinctions of ...superabundant species with very large ranges are rare. The Yellow‐breasted Bunting (Emberiza aureola) used to be one of the most abundant songbirds of the Palearctic, with a very large breeding range stretching from Scandinavia to the Russian Far East. Anecdotal information about rapid population declines across the range caused concern about unsustainable trapping along the species’ migration routes. We conducted a literature review and used long‐term monitoring data from across the species’ range to model population trend and geographical patterns of extinction. The population declined by 84.3–94.7% between 1980 and 2013, and the species’ range contracted by 5000 km. Quantitative evidence from police raids suggested rampant illegal trapping of the species along its East Asian flyway in China. A population model simulating an initial harvest level of 2% of the population, and an annual increase of 0.2% during the monitoring period produced a population trajectory that matched the observed decline. We suggest that trapping strongly contributed to the decline because the consumption of Yellow‐breasted Bunting and other songbirds has increased as a result of economic growth and prosperity in East Asia. The magnitude and speed of the decline is unprecedented among birds with a comparable range size, with the exception of the Passenger Pigeon (Ectopistes migratorius), which went extinct in 1914 due to industrial‐scale hunting. Our results demonstrate the urgent need for an improved monitoring of common and widespread species’ populations, and consumption levels throughout East Asia.
The transition from a command to a market economy resulted in widespread cropland abandonment across the former Soviet Union during the 1990s. Spatial patterns and determinants of abandonment are ...comparatively well understood for European Russia, but have not yet been assessed for the vast grain belt of Western Siberia, situated in the Eurasian forest steppe. This is unfortunate, as land-use change in Western Siberia is of global significance: Fertile black earth soils and vast mires store large amounts of organic carbon, and both undisturbed and traditional cultural landscapes harbor threatened biodiversity. We compared Landsat images from ca. 1990 (before the break-up of the Soviet Union) and ca. 2015 (current situation) with a supervised classification to estimate the extent and spatial distribution of abandoned cropland. We used logistic regression models to reveal important determinants of cropland abandonment. Ca. 135,000 ha classified as cropland around 1990 were classified as grassland around 2015. This suggests that ca. 20% of all cropland remain abandoned ca. 25 years after the end of the Soviet Union. Abandonment occurred mostly at poorly drained sites. The likelihood of cropland abandonment increased with decreasing soil quality, and increasing distance to medium-sized settlements, roads and railroads. We conclude that soil suitability, access to transport infrastructure and availability of workforce are key determinants of cropland abandonment in Western Siberia.
► Changes in agriculture after the break-up of the Soviet Union were largely beneficial for bird populations of the Eurasian steppes. ► Future reclamation of abandoned arable land and changing ...grazing patterns are predicted to lead to new habitat loss. ► Possible conservation solutions might include improvements to the protected area system in Kazakhstan and land-sparing approaches.
The socioeconomic impacts of the break-up of the Soviet Union after 1991 have resulted in massive changes in agriculture on the Eurasian (Pontian) steppe, most of which is now confined to Kazakhstan. Recent trends in agriculture are well documented but their impacts on the characteristic bird community of this vast region, which contains over 10% of the world’s remaining grasslands, are poorly understood. We modelled bird population density in a representative region in central Kazakhstan along a land-use gradient ranging from pristine steppe to arable fields and heavily grazed pastures. Long-abandoned arable fields and ungrazed pristine steppe were the most important habitats for most species, and post-1991 abandonment of arable agriculture suggests that many species have enjoyed a period of significant population growth. Livestock concentration effects, leading to high grazing pressure in small areas, are also likely to have benefitted several species of high conservation concern. However, analysis of land-use statistics and socioeconomic surveys among land managers suggest that recent and predicted future trends in agriculture in the steppe zone, particularly the reclamation of abandoned cereal fields and reduced grazing pressure, may cause populations of most species, including a number of biome-restricted species, to decline in the near future. We discuss possible conservation solutions, including improvements in the protected area system and land-sparing options.
Passive acoustic monitoring (PAM) has gained increasing popularity to study behaviour, habitat preferences, distribution and community assembly of birds and other animals. Automated species ...classification algorithms like ‘BirdNET’ are capable of detecting and classifying avian vocalizations within extensive audio data, covering entire species assemblages. PAM reveals substantial potential for biodiversity monitoring that informs evidence‐based conservation. Nevertheless, fully realizing this potential remains challenging, especially due to the issue of false‐positive species detections. Here, we introduce an optimized thresholding framework, which incorporates contextual information extracted from the time‐series of automated species detections (i.e. covariates on quality and quantity of species' detections measured at varying time intervals) to improve the differentiation of true and false positives. We verified a sample of BirdNET detections per species and modelled species‐specific thresholds using conditional inference trees. These thresholds were designed to minimize false‐positive detections while maximizing the preservation of true positives in the dataset. We tested this framework for a large dataset of BirdNET detections (5760 h of audio data, 60 sites) recorded over an entire breeding season. Our results revealed considerable interspecific variability of precision (percentage of true positives) within raw BirdNET data. Our optimized thresholding approach achieved high precision (≥0.9) for 70% of the 61 detected species, while species‐specific thresholds solely relying on the BirdNET confidence scores achieved high precision for only 31% of the species. Conservative universal thresholds (not species‐specific) reached high precision for 48% of the species. Our thresholding approach outperformed previous thresholding approaches and enhanced interspecific comparability for bird community analyses. By incorporating contextual information from the time‐series of species detections, the differentiation of true and false positives was substantially improved. Our approach may enhance a straightforward application of PAM in biodiversity research, landscape planning and evidence‐based conservation.
Passive acoustic monitoring is a valuable tool for studying birds, but it faces challenges with false positive species detections. We present an optimized thresholding approach that uses contextual information from time‐series of species detections to improve the true positive rates of automated species detections. Our approach achieved high true positive rates for 70% of 61 considered species, outperforming previous approaches. This framework may facilitate the application of passive acoustic monitoring in biodiversity research and conservation by a wide audience.
Much of our knowledge about land use and ecosystem services in interrelated social-ecological systems is derived from place-based research. While local and regional case studies provide valuable ...insights, it is often unclear how relevant this research is beyond the study areas. Drawing generalized conclusions about practical solutions to land management from local observations and formulating hypotheses applicable to other places in the world requires that we identify patterns of land systems that are similar to those represented by the case study. Here, we utilize the previously developed concept of land system archetypes to investigate potential transferability of research from twelve regional projects implemented in a large joint research framework that focus on issues of sustainable land management across four continents. For each project, we characterize its project archetype, i.e. the unique land system based on a synthesis of more than 30 datasets of land-use intensity, environmental conditions and socioeconomic indicators. We estimate the transferability potential of project research by calculating the statistical similarity of locations across the world to the project archetype, assuming higher transferability potentials in locations with similar land system characteristics. Results show that areas with high transferability potentials are typically clustered around project sites but for some case studies can be found in regions that are geographically distant, especially when values of considered variables are close to the global mean or where the project archetype is driven by large-scale environmental or socioeconomic conditions. Using specific examples from the local case studies, we highlight the merit of our approach and discuss the differences between local realities and information captured in global datasets. The proposed method provides a blueprint for large research programs to assess potential transferability of place-based studies to other geographical areas and to indicate possible gaps in research efforts.
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