Extensive Livestock Grazing Research Articles

Recent changes in the plant composition of wetlands in the Jura Mountains

AbstractAimTo assess vegetation changes in montane fens and wet meadows and their causes over 38 years.LocationWetlands, Jura Mountains (Switzerland and France).MethodsPlots were inventoried in 1974 and re‐located in 2012 (quasi‐permanent plots) on the basis of sketches to assess changes in plant communities. The 110 plots belonged to five phytosociological alliances, two in oligotrophic fens (Caricion davallianae, Caricion fuscae) and three in wet meadows (Calthion, Molinion, Filipendulion). Changes between surveys were assessed with NMDS, and changes in species richness, Simpson diversity, species cover and frequency and the causes of these changes were evaluated by comparing ecological indicator values.ResultsChanges in species composition varied between alliances, with a general trend towards more nutrient‐rich flora with less light at ground level. Species diversity declined, with a marked decreasing trend for the typical species of each alliance. These species were partly replaced by species belonging to nitrophilous and mesophilous grasslands. However, no trend towards drier conditions was detected in these wetlands. The largest changes, with an important colonization by nitrophilous species, occurred in the Swiss sites, where grazing was banned 25 years ago. As a result of floral shifts, many plots previously belonging to fens or wet mesotrophic meadows shifted to an alliance of the wet meadows, generally Filipendulion. Moreover, communities showed a slight trend towards more thermophilous flora.ConclusionsThe investigated wetlands in the Jura Mountains have suffered mainly from eutrophication due to land‐use abandonment and N deposition, with a loss of typical species. Areas with constant land use (grazing or mowing) showed less marked changes in species composition. The most important action to conserve these wetlands is to maintain or reintroduce the traditional practices of extensive mowing and livestock grazing in the wetlands, especially in areas where they were abandoned 25 years ago. This previous land‐use change was intended to improve fen conservation, but it was obviously the wrong measure for conservation purposes.

Effects of grazing abandonment on soil multifunctionality: The role of plant functional traits

Abstract Extensive livestock grazing is a global land use activity that has numerous social, cultural, and environmental benefits. Many marginal zones grazed for centuries are now suffering from abandonment, which has been found to be interrelated with species and functional diversity loss, and has potential consequences for the provision of ecosystem services such as soil fertility and soil carbon storage. We sampled soil and plant species abundance in a total of 64 plots (5 × 5 m), in wet and dry habitats under different grazing regimes (from moderate grazing to grazing abandonment for at least 30 years) in Central Spain. We tested the influence of grazing intensity and water availability on different variables related to soil fertility and also on soil carbon storage. In addition, Community weighted mean and Rao quadratic entropy were calculated for two effect traits (specific leaf area and plant height), in order to assess the ultimate effects of these functional attributes on multifunctionality (i.e., the provision of several simultaneous ecosystem functions). We found that grazing abandonment generally produces a reduction in soil organic matter, total nitrogen, available potassium and phosphorus, aggregate stability and soil carbon storage. In addition, grazing abandonment had a negative effect on soil texture with loss of fine particles (clay and silt) and water holding capacity, but only in dry habitats and in longer-term abandoned situation. In general, soil multifunctionality was higher in wet than dry habitats, decreased with grazing abandonment in both habitats. Soil multifunctionality was indirectly mediated by the functional structure of size and leaf traits of the local plant communities, but our results suggested that macroscale grazing effects, i.e. translocation of nutrients by grazers among habitats via dung and urine deposition, might be important mechanisms that influence soil multifunctionality at the local level. Agri-environmental policies should be aware of the risk of widespread grazing abandonment and take advantage of the benefits of low-intensity grazing regimes for ecosystem services such as soil fertility and stability, and soil carbon storage.

Technical efficiency and the impact of grassland use right leasing on livestock grazing on the Qinghai-Tibetan Plateau

This paper reviews changes in grassland property rights and measures the efficiency of livestock grazing on China’s Qinghai-Tibetan Plateau, where there is an extensive nomadic grazing system. A cross sectional data set from a field survey of 197 livestock grazing households is used to develop a stochastic translog distance function and technical inefficiency model; variables for livestock intensity and property rights are incorporated. The overall average technical efficiency of the extensive livestock grazing is estimated to be 0.62, lower than the value of 0.67 found for households who rent-in grassland. The results indicate that renting-in grassland improves the technical efficiency of livestock grazing significantly. Both household size and livestock intensity have an effect on technical efficiency, especially the dummy variable of whether the summer pasture is near the winter pasture. This may indicate that grassland fragmentation would be not ideal for extensive livestock production on the Qinghai-Tibetan Plateau.

Can dung beetles (Scarabaeinae) indicate the status of Amazonia’s ecosystems? Insights integrating anthropogenic disturbance with seasonal patterns

Temporal and spatial variation in dung beetles abundances is a pattern observed in many tropical forests. The present study evaluated the seasonal patterns of dung beetles in a range of increasingly disturbed ecosystems of the state of Pará, northern Brazil, to identify valuable disturbance indicators. The areas included native forest, agriculture, pasture for extensive livestock grazing and secondary forests. Fieldwork was carried out encompassing the complete range of environmental conditions encountered during the year. In total, 13,649 individuals were captured within 23 genera and 99 species but with pronounced differences among ecosystems and seasons. The obtained results seem to demonstrate that dung beetles can be used to help identify ecosystems under very complex and variable environmental conditions. The ecological drift observed also demonstrates the possibility of using dung beetles as ecological indicators of disturbance in Amazonia.

Long-term agricultural land-cover change and potential for cropland expansion in the former Virgin Lands area of Kazakhstan

During the Soviet Virgin Lands Campaign, approximately 23 million hectares (Mha) of Eurasian steppe grassland were converted into cropland in Northern Kazakhstan from 1954 to 1963. As a result Kazakhstan became an important breadbasket of the former Soviet Union. However, the collapse of the Soviet Union in 1991 triggered widespread agricultural abandonment, and much cropland reverted to grasslands. Our goal in this study was to reconstruct and analyze agricultural land-cover change since the eve of the Virgin Lands Campaign, from 1953 to 2010 in Kostanay Province, a region that is representative of Northern Kazakhstan. Further, we assessed the potential of currently idle cropland for re-cultivation. We reconstructed the cropland extent before and after the Virgin Lands Campaign using archival maps, and we mapped the agricultural land cover in the late Soviet and post-Soviet period using multi-seasonal Landsat TM/ETM+ images from circa 1990, 2000 and 2010. Cropland extent peaked at approximately 3.1 Mha in our study area in 1990, 38% of which had been converted from grasslands from 1954 to 1961. After the collapse of the Soviet Union, 45% of the Soviet cropland was abandoned and had reverted to grassland by 2000. After 2000, cropland contraction and re-cultivation were balanced. Using spatial logistic regressions we found that cropland expansion during the Virgin Lands Campaign was significantly associated with favorable agro-environmental conditions. In contrast, cropland expansion after the Campaign until 1990, as well as cropland contraction after 1990, occurred mainly in areas that were less favorable for agriculture. Cropland re-cultivation after 2000 was occurring on lands with relatively favorable agro-environmental conditions in comparison to remaining idle croplands, albeit with much lower agro-environmental endowment compared to stable croplands from 1990 to 2010. In sum, we found that cropland production potentials of the currently uncultivated areas are much lower than commonly believed, and further cropland expansion is only possible at the expense of marginal lands. Our results suggest if increasing production is a goal, improving crop yields in currently cultivated lands should be a focus, whereas extensive livestock grazing as well as the conservation of non-provisioning ecosystem services and biodiversity should be priority on more marginal lands.

Pervasive early 21st‐century vegetation changes across Danish semi‐natural ecosystems: more losers than winners and a shift towards competitive, tall‐growing species

Summary Semi‐natural open habitats in north‐western Europe are highly prioritized for conservation, and optimization of management planning is essential for continued protection of their diversity. We evaluate whether current management practices, which consist mainly of summer grazing by livestock, are sufficient to maintain plant species composition in a stable state across semi‐natural areas in Denmark, or if shifts in functional composition are taking place. Further, we investigate important drivers of any ongoing changes through trait differences between winner and loser species. Using a data set of 6513 annually inventoried (2004–2010) vegetation plots from 202 semi‐natural NATURA 2000 protected areas, we assessed changes in cover of all plant species and, using boosted regression trees, whether winners and losers differ in regard to autecological characteristics and traits. There were consistent changes in cover for 123 out of 603 species across the 6‐year study period, with more species losing than winning (78 vs. 45). Winner and loser species were strongly differentiated by competition‐related traits, but traits related to soil nutrients and soil moisture also had some importance. Generally, our results indicate a trend towards taller and more competitive species. Synthesis and applications. Despite conservation actions in order to maintain a so‐called favourable conservation status, vegetation in NATURA 2000 protected areas is still undergoing compositional changes. Overall, autecological characteristics and trait differences between winners and losers match expectations given the contemporary anthropogenic pressures, especially reduced livestock grazing. Atmospheric nitrogen deposition and increased soil moisture due to reduced drainage might also be involved in observed changes. Current management (i.e. summer grazing by livestock) is insufficient to preserve the diversity of less‐competitive, low‐statured and stress‐tolerant herbaceous species, potentially leading to species losses. Such patterns can thus be expected across semi‐natural ecosystems in north‐western Europe and other places where traditional land use (i.e. previous widespread extensive livestock grazing) have been replaced with various degrees of conservation management. A greater focus on returning large grazing herbivores to conservation areas is recommended for the protection of plant species diversity and to counteract ongoing changes.

Plantaciones forestales vs. regeneración natural in situ : El caso de los pinos y la rehabilitación en el Parque Nacional Cofre de Perote

El conocimiento de la estructura y dinámica de la vegetación como estimadores del desempeño de las plantaciones forestales y de la regeneración natural en la rehabilitación es escaso, y tampoco se conoce el efecto de la ganadería extensiva sobre ambas. El objetivo de este estudio fue comparar el número de individuos por hectárea y la tasa anual de crecimiento entre las comunidades de pinos ( Pinus patula , P. montezumae y P. teocote ) procedentes de las plantaciones forestales y de la regeneración natural en sitios con dos diferentes condiciones (con y sin exclusión de ganado). Se encontraron diferencias significativas (P < 0.0001) en la tasa anual de crecimiento de la altura, en el diámetro basal del tallo y en el diámetro promedio de cobertura entre las plantaciones vs . la regeneración natural y entre las dos condiciones de exclusión de ganado. El número de individuos establecidos por hectárea fue significativamente mayor en la regeneración natural con exclusión de ganado (1,380 ± 120 y 1,130 ± 130) que en aquella sin exclusión (430 ± 250), y en las plantaciones forestales con o sin exclusión de ganado (995 ± 90 y 455 ± 125, respectivamente; P < 0.0001). Se concluye que la regeneración natural de pinos es una opción adecuada para la rehabilitación ecológica en terrenos degradados, especialmente si están protegidos del ganado, en comparación con las plantaciones forestales.

Diversity and floristic patterns of mediterranean grasslands: the relative influence of environmental and land management factors

Managed grasslands are normally ecosystems with high species diversity. They are associated with traditional extensive livestock grazing. Land-use changes, in particular gradual abandonment or grazing intensification, lead to major changes in floristic patterns of these grasslands, some included in priority habitats of the EU Habitats Directive. In order to analyse these patterns of change, Mediterranean grasslands of eastern areas of mainland Portugal were studied aiming to: (1) establish ecological gradients underlying their floristic patterns; (2) examine the relative importance of both environmental and land-use factors on their floristic composition; (3) assess how floristic composition and species richness are affected by land-use factors. Vegetation sampling was carried out from 2008 to 2009 following phytosociological procedures. Canonical Correspondence Analysis was applied. Variation partitioning was used to assess the relative influence of land-use variables. Richness, legumes cover, endemic species and bryophytes cover were compared in four land-management regimes: unmanaged; extensive grazing by sheep; extensive grazing by cattle and sheep; frequent soil tillage. Significant differences were found in floristic and diversity patterns, revealing the importance of grazing as a management tool for maintaining or improving floristic diversity. From our findings slight extensive grazing can contribute to both maintenance of species diversity and to the increase in legumes cover and thus to palatability and economic value of studied grasslands. Interactions between herbivores and grasslands, considering also their influences on soil properties, have an important role in the equilibrium states which promote biodiversity and conservation of the services of these ecosystems.

The impact of changing rainfall variability on resource-dependent wealth dynamics

Climate change is widely expected to lead to changing rainfall variability and thus to changing frequency of drought. In places where drought is a major driver of agroecosystem dynamics, as in the extensive livestock grazing systems that dominate Africa's sprawling arid and semi-arid lands, changing rainfall variability can fundamentally alter human wealth dynamics. We use subjective livestock herd growth expectations data elicited from Boran pastoralists in southern Ethiopia to generate estimates of herd dynamics conditional on rainfall state. The climate state-conditional estimates permit simulation of herd dynamics under different rainfall patterns. The multiple herd size equilibria observed in multiple pastoralist household data sets from the region appear sensitive to climate regimes. Reduced rainfall variability that significantly reduces drought frequency would eliminate, in expectation, the poverty trap equilibrium that presently exists only for households with herd sizes beneath a threshold level. Conversely, if the drought frequency more than doubles relative to recent patterns, then the whole system becomes a poverty trap, in expectation.

Land-use and land-cover effects on regional biodiversity distribution in a subtropical dry forest: a hierarchical integrative multi-taxa study

Latin American subtropical dry ecosystems have experienced significant human impact for more than a century, mainly in the form of extensive livestock grazing, forest products extraction, and agriculture expansion. We assessed the regional-scale effect of land use and land cover (LULC) on patterns of richness distribution of trees, birds, amphibians, and mammals in the Northern Argentine Dry Chaco (NADC) over c. 19 million hectares. Using species distribution models in a hierarchical framework, we modeled the distributions of 138 species. First, we trained the models for the entire Argentinean Chaco with climatic and topographic variables. Second, we modeled the same species for the NADC including the biophysical variables identified as relevant in the first step plus four LULC-related variables: woody biomass, distance to crops, density of livestock-based rural settlements (puestos), and vegetation cover. Third, we constructed species richness maps by adding the models of individual species and considering two situations, with and without LULC variables. Four, richness maps were used for assessing differences when LULC variables are added and for determining the main drivers of current patterns of species richness. We found a marked decrease in species richness of the four groups as a consequence of inclusion of LULC variables in distribution models. The main factors associated with current richness distribution patterns (both negatively) were woody biomass and density of livestock puestos. Species richness in present-day Semiarid Chaco landscapes is strongly affected by LULC patterns, even in areas not transformed to agriculture. Regional-scale biodiversity planning should consider open habitats such as grasslands and savannas in addition to woodlands.

Decline of traditional landscape in a protected area of the southwestern Alps: The fate of enclosed pasture patches in the land mosaic shift

Traditional landscape elements such as pasture patches enclosed in a forest matrix are progressively disappearing throughout the European Alps. We assessed the land mosaic shift of a protected area located in the western Italian Alps. In particular, the dynamics of pasture patches were studied at both landscape and stand level. Land-cover mapping through object-oriented analysis of historical aerial photographs was used to assess land-cover changes between 1954 and 2000. Spatial statistics were used to quantify landscape patterns, and field samplings within pasture patches were used to explore tree regeneration structure and composition. Our results showed a significant increase in the number of pasture patches caused by their fragmentation following forest expansion. The total surface area of pasture patches decreased by 43% and their core area decreased by 94%. The encroachment of trees on less accessible areas of the pasture patches caused a reduction of patch shape at landscape scale. The gap filling process started 40-50 years ago and began with an early invasion of light demanding species like sycamore maple (Acer pseudoplatanus L.) and common ash (Fraxinus excelsior L.), followed by European beech (Fagus sylvatica L.) and secondarily silver fir (Abies alba Mill.). Traditional land-use and population decline in the Pesio Valley led to a reduction in ecotone areas. A transition to a more homogeneous landscape is expected in the next decades. Given the cultural and productive nature of these mountain meadow-pasture communities, extensive livestock grazing systems could be used to manage their future conservation.

The Use of Goats Grazing to Restore Pastures Invaded by Shrubs and Avoid Desertification: A Preliminary Case Study in the Spanish Cantabrian Mountains

AbstractSpanish mountains have been affected by the expansion of shrubs and forests since the mid‐20th century. This secondary succession in vegetation has some positive effects, but also drawbacks, such as an increase in fire risk, loss of diversity in land use, a reduction in landscape and cultural value, less water available in river channels and reservoirs, constraints on livestock farming, a reduced number of local species and loss of biodiversity. This paper analyses the potential for grazing domestic goats to help control the spread of several species of shrubs such as the common broom (Cytisus scoparius), red raspberry (Rubus idaeus) and roses (Rosasp.) that are commonly found in degraded pastures in the Cantabrian Mountains of northern Spain. Using experimental plots, the effects of two levels of stocking density (4·5 and 9 goats ha−1y−1) are compared with other land management systems used in the region: burning, mechanical clearing and trimming. The combined use of goats with support from burning, clearing and trimming controls the spread of shrubs. The most efficient treatment was found with nine goats ha−1y−1. Goat grazing also changes the distribution of shrubs, transforming a dense and continuous coverage into separate clumps and thereby enabling livestock to graze more easily. Maintaining a mixed structure of shrubs and pastures is the best treatment due to the low population density of the Cantabrian Mountains, as this enhances the biodiversity, controls fire risk and enriches the landscape; it also allows extensive livestock grazing as a main economic resource. Copyright © 2013 John Wiley & Sons, Ltd.

A geospatial model for the optimization grazing management in semi-arid rangeland of Iran

Extensive livestock grazing even in unsuitable land has increasingly grown in most parts of semi-arid rangeland. Therefore, it is of paramount importance to identify suitable land for livestock grazing for optimum utilization while causing minimum impact to the environment. This paper adapted the schematic model based on the concepts presented by the Food and Agriculture Organization of suitability analysis for optimal grazing management in semi-arid rangeland in Iran. Factors affecting extensive grazing were determined and incorporated into the model. Semi-arid rangeland with variable such as climate and other agents were examined for common types of animal grazing and the advantages and limitations were elicited. Many ecosystem components affect land suitability for livestock grazing but due to time and funding restrictions, the most important and feasible elements were investigated. Within the model parameters, three submodels including water accessibility source, forage production, and erosion sensitivity were considered. Suitable areas at four levels of suitability were determined using geographic information systems. This suitability modeling approach was adopted due to its simplicity and the minimal time required for transforming and analyzing datasets. The most important reducing factors in model suitability were found to be: (a) land use and vegetation cover (in relation to soil erosion sensitivity), (b) the amount of the available forage in comparison with the total production, and (c) the existence of less palatability plants among the pasture plant species (forage production suitability). The results of the study would be beneficial to rangeland managers in devising measures more wisely to cope with the limitations and enhance the health and productivity of the rangelands.

Land-use influence on Mediterranean perennial swards of "Poa bulbosa": a case study in the International Tagus Region

Pastureland abandonment or intensification of livestock activity change the floristic patterns of Mediterranean perennial swards which are very important to the conservation of some bird species. The objectives of this study are: 1) to recognise floristic patterns in Mediterranean perennial swards of Poa bulbosa; 2) to identify the communities that configure the European priority habitat 6220* (Pseudo-steppe with grasses and annuals of the Thero-Brachypodietea); 3) to assess the effects of land-use management on the floristic composition of these communities. Field research was conducted in central eastern and south eastern main land Portugal.Vegetation sampling was carried out in 2009-2010 on 9 sward sites, following the phytosociological concepts. Classification and ordination of relevés were obtained by Two Way Indicator Species Analysis (TWINSPAN), Canonical Correspondence Analysis (CCA) and Detrended Canonical Correspondence Analysis (DCCA). Monte Carlo Permutation Tests were performed to analyse differences in floristic patterns. Livestock load, stoniness and land-use history of the last 10 years were selected as the key variables that best explain the ordination model. The absence of extensive livestock grazing results in a reduction of Trifolium subterraneum-dominated areas and in a density/ cover reduction of Poa bulbosa-dominated areas. High livestock loads change the floristic patterns of Mediterranean short swards by favouring species of the Stellarietea mediae class. The control of woody vegetation through grazing or cutting is a key conservation measure.

Stimulateurs et défibrillateurs cardiaques et interférences électromagnétiques au travail

Extensive livestock grazing is a global land use activity that has numerous social, cultural, and environmental benefits. Many marginal zones grazed for centuries are now suffering from abandonment, which has been found to be interrelated with species and functional diversity loss, and has potential consequences for the provision of ecosystem services such as soil fertility and soil carbon storage. We sampled soil and plant species abundance in a total of 64 plots (5 × 5 m), in wet and dry habitats under different grazing regimes (from moderate grazing to grazing abandonment for at least 30 years) in Central Spain. We tested the influence of grazing intensity and water availability on different variables related to soil fertility and also on soil carbon storage. In addition, Community weighted mean and Rao quadratic entropy were calculated for two effect traits (specific leaf area and plant height), in order to assess the ultimate effects of these functional attributes on multifunctionality (i.e., the provision of several simultaneous ecosystem functions). We found that grazing abandonment generally produces a reduction in soil organic matter, total nitrogen, available potassium and phosphorus, aggregate stability and soil carbon storage. In addition, grazing abandonment had a negative effect on soil texture with loss of fine particles (clay and silt) and water holding capacity, but only in dry habitats and in longer-term abandoned situation. In general, soil multifunctionality was higher in wet than dry habitats, decreased with grazing abandonment in both habitats. Soil multifunctionality was indirectly mediated by the functional structure of size and leaf traits of the local plant communities, but our results suggested that macroscale grazing effects, i.e. translocation of nutrients by grazers among habitats via dung and urine deposition, might be important mechanisms that influence soil multifunctionality at the local level. Agri-environmental policies should be aware of the risk of widespread grazing abandonment and take advantage of the benefits of low-intensity grazing regimes for ecosystem services such as soil fertility and stability, and soil carbon storage.

Conservation and grazing in Australia’s north-east: the bridled nailtail wallaby

Australia’s vast continent is dominated by semi-arid and arid landscapes that have been modified to support the development of an extensive livestock grazing industry. Historically, this development has come at great environmental cost, with wide-scale landscape degradation and loss of biodiversity, including small macropods. With the growing appreciation of environmental values and ecological services provided by grazing landscapes, the engagement of pastoral landholders is now central to contemporary conservation efforts. In this paper we explore the spluttering recovery of Australia’s critically endangered bridled nailtail wallaby Onychogalea fraenata, once presumed extinct but now subject to a limited rehabilitation program in Queensland. We explore the ‘fit’ between management units and the scale of conservation challenges for the bridled nailtail wallaby, and then use this to frame the role of the private grazing industry in the governance of conservation actions. A centralised state conservation program has largely failed to stop the decline of the species, which remains critically endangered. We argue that non-state (privately) managed grazing properties working within a multi-level governance system that includes the state have a greater chance of conservation success because their actions can more appropriately match the scale of the problem at the implementation level. If the species recovers, the balance of management focus will need to shift towards broader scale actions such that localised disconnected sub-populations can successfully interbreed. By analysing the institutional failures that surround the bridled nailtail wallaby, we provide recommendations on how public institutions or policies can successfully catalyse private sector action at regional scales. These include avoiding economic incentives that may crowd out local stewardship, avoiding overly-authoritative state control (i.e. mono-centricity), and developing a multilevel governance structure that can strategically adapt its focus to the scale of various and shifting targets.

Spatial heterogeneity and farmland birds: different perspectives in Western and Eastern Europe

One of the most dramatic declines of biodiversity in Europe has been the collapse of farmland bird populations (Donald et al. 2006). The loss of habitat heterogeneity is suggested as being an important driver behind this loss, and operates at a range of spatial scales from specialization of land-use on farms and across farmed landscapes to the disappearance of hedgerows and fallows and the homogenization of crop sward structure (Benton et al. 2003). Most of our knowledge of agricultural practices and farmland bird ecology, however, is from a few countries only, with 76% of papers in the Web of Science originating from the UK, France, Netherlands, Spain, Germany and Sweden, and less than 10% from Central and Eastern European countries (Donald et al. 2002, Kleijn & Baldi 2005, paper numbers are from a search on the Web of Science from 1975 to 28 August 2010 for ‘(‘agricultur*’ OR farmland) AND (‘species richness’ OR biodivers*) AND bird*’). Common features of most of these Western countries are the severe long-term decline of farmland bird populations and high levels of agricultural intensification (use of agrochemicals, mechanization, etc.). Most Central and Eastern European countries (CEECs) experience different biogeographical and climatic conditions, and have different economic and agricultural conditions with recent entry to the EU and the application of the Common Agricultural Policy, and a change from a socialist to market-regulated economy in the 1990s. Therefore, most of the knowledge on farmland bird ecology only partially covers the variation in farming systems, bird population status, biogeographical conditions and socioeconomic background across Europe. Inevitably, any generalization based on this biased knowledge may be misleading (Kleijn & Baldi 2005, Whittingham et al. 2007). We highlight a potential problem if research evidence were to be generalized across different parts of Europe to guide conservation strategies, for example by applying knowledge of farmland bird ecology in Western Europe to the CEECs. We focus on farmland heterogeneity as an example because this is delivered by a wide range of management options in agri-environment schemes (AES) designed to reverse biodiversity losses. These include the creation and maintenance of hedgerows, beetle banks or field margins. Many studies have indicated a positive correlation between species richness or abundance of farmland birds and landscape heterogeneity (Benton et al. 2003), but these results were based mostly on Western European evidence, and a critical evaluation of the impact of farmland heterogeneity across European farmland systems is still missing. Indeed, there is an increasing interest in the topic recently due to several still open questions, of which geographical restriction is only one (Batary et al. 2011, Fahrig et al. 2011, Pickett & Siriwardena in press). Heterogeneity of farmland has changed during the history of agriculture (e.g. Sutherland 2004). These changes include land conversions and shifts in landscape-level patterns. Therefore, heterogeneity should only be promoted if there is evidence that biodiversity loss stems from loss of previous heterogeneity. Many Western European grasslands, for example, were heavily homogenized in the 20th century, as stone walls and hedges were removed to create large, economically more profitable fields (Robinson & Sutherland 2002). However, in some cases the original landscapes may have been more homogeneous than the modern systems that have replaced them. In such cases, increasing heterogeneity may result in further habitat fragmentation, with harmful consequences to the original biodiversity (Fahrig 2003). Examples are large-scale semi-natural grassland systems in CEECs, such as the puszta grasslands in Hungary. These semi-natural grasslands cover more than 1 million hectares in Hungary and are the result of centuries of extensive livestock grazing. The baseline system is a vast open landscape with grasslands scattered with small wetlands, a few trees, woodlots and farms (Baldi et al. 2005). Accordingly, recent conservation management actions in these grassland landscapes aim to decrease heterogeneity, with the removal of structures such as lines of bushes in the pastures of Kiskunsag National Park (http://www.knp.hu), or hundreds of kilometres of drainage channels in the Hortobagy National Park (http://www.hnp.hu). There is therefore evidence of a beneficial role of homogeneous farmland landscapes from different areas of Europe. These include the nega*Corresponding author. Email: andrasbaldi@gmail.com

Diet of the Eurasian Black Vulture, Aegypius monachus Linnaeus, 1766, in Turkey and implications for its conservation

We analysed 120 pellets of the Eurasian Black Vulture, Aegypius monachus Linnaeus, 1766, collected in Turkey during the breeding season in order to assess diet preference and implications for conservation. In addition, we were able to analyse the stomach content of a dead individual. The most abundant prey item was sheep, which was found in 76.6% of all pellets, followed by Wild Boar (44.1%) and chicken (22.5%). This shows that livestock plays an outstanding role in the diet of the Eurasian Black Vulture, and underlines its dependence on extensive livestock farming and grazing. Dumping livestock carcasses around the vultures’ breeding sites should therefore be permitted. In order to minimise the risk of poisoning, it should be forbidden to dispose of contaminated or poisoned carcasses in natural areas.

The influence of fine-scale habitat heterogeneity on invertebrate assemblage structure in upland semi-natural grassland

The Scottish uplands consist of a variety of semi-natural habitats of high nature value that are typically managed by extensive livestock grazing. However, as a result of the decoupling of financial subsidies from production in the recent Common Agricultural Policy reform, sheep numbers in the uplands have significantly declined and there is concern that the conservation value of these habitats is at risk. A large-scale experiment that manipulated sheep grazing management provided an excellent opportunity to examine the influence of fine-scale habitat characteristics on invertebrate assemblages. A Geographical Information System was used to extract habitat data at four spatial scales ranging from 0.25 m to 5.0 m in ellipses around pitfall transects. Multivariate analyses were applied to determine the most appropriate spatial scale and the primary habitat characteristics influencing three categories of invertebrates (i.e., mobile arthropods, immobile invertebrates and carabid beetles). Sites that were grazed year-round, and thus more intensively, were associated with smaller mobile arthropods (e.g., money spiders), tipulid larvae and earthworms, while sites that were grazed during summer months only were associated with larger mobile arthropods (e.g., wolf spiders and Carabus beetles) and sawfly and lepidopteran larvae. Grazing regime and the area of fine and broad-leaved grasses were found to influence all three groups of invertebrates at a range of spatial scales, thus indicating the importance of these variables in predicting assemblage structure. The optimum spatial scale at which to collect associated habitat information was from within 0.25 m for immobile invertebrates, and from within 3 m for mobile arthropods and carabids. This supports the hypothesis that immobile invertebrates react to their surrounding habitat at a finer spatial scale than mobile invertebrates and draws into question the effectiveness of collecting habitat information from directly adjacent to the pitfall traps when studying mobile arthropods.

N and P dynamics in the litter layer and soil of Mexican semi-arid forests, state of Morelos

In central Mexico, it is common for farmers to retain useful trees in abandoned lands after maize cultivation, creating a park-like landscape of scattered trees for extensive livestock grazing, among other land uses (mature forests, secondary forests, and livestock grazing in secondary forests). Among these trees Acacia cochliancantha and Ipomoea arborescens are the most common species associated with this land use in the region. The objective of this study was to assess the effects of both tree species on soil N and P recycling. To this end, we measured N and P concentrations in leaves of both species; and the seasonal N and P (total and dissolved) content in the litter, and total N and P, inorganic N, and bicarbonate-extractable-P concentrations, and the N transformations in the soil, in samples collected under crown of Acacia and Ipomoea and in open areas. Trees of different species varied in their capacity to cycle N. The leaves of Acacia were richer in N than those of Ipomoea (29.7 and 25.0 mg N g −1, respectively), and nutrient resorption was higher in leguminous trees than in Ipomoea (by 20% in the case of N, and 35% in the case of P). Acacia trees had higher effects on soils than Ipomoea trees, like consistent increases of N concentrations (by 30% in the case of total N, and by ∼50% in the case of inorganic N) and transformations (N mineralization and nitrification in rainy season increases by a factor of 20 and 36, respectively). On the other hand, Ipomoea produced senescent leaves and accumulated forest litter with less P concentration (0.8 and 0.7 mg P g −1, respectively) in relation to Acacia (senescent leaves: 1.3 mg P g −1; litter: 1.1 mg P g −1), reflecting the lower availability of the nutrient in the soil. The total litter N and P pools decreased in the rainy season under crown of both species, as the dissolved P pool did. The total soil N and P concentrations did not change with sampling season. However, potential N transformations and bicarbonate P under both species were higher in dry season than in rainy season samples. Comparison with other land uses in the region suggests that the Acacia– Ipomoea system cycles low quantity of nutrients, but there are no notable differences in the availability of P in the soils. These results demonstrate that scattered trees improve the N and P cycling following the discontinuation of agricultural practices, and the effects will vary depending on the tree species.