Lluís

1. Understanding ecosystem responses to disturbance is important for effective management of biodiversity. Observed relationships between time since disturbance and diversity have taken a variety of forms, only some of which are explicitly predicted in models of vegetation succession. This makes generalization and predictions for specific communities difficult.
2. Negative relationships have been the predominant diversity response to time since fire in fire-prone Mediterranean-climate ecosystems; however, few studies have analysed responses in infrequently burnt ecosystems such as Mediterranean-climate woodlands dominated by fire-sensitive trees. We used a space-for-time approach and multiple stand-ageing techniques (Landsat imagery, growth ring counts and growth ring–size relationships) to characterize diversity and compositional changes with time since fire (3–370+ years) in fire-sensitive Eucalyptus salubris woodlands in south-western Australia.
3. Species density and Pielou's evenness showed an overall ‘U’-shaped response to time since fire, although variability between plots was considerable. Plant functional type and species composition differed with time since fire, with greater richness and cover of ground layer, and ‘long dispersal potential’ functional types with increasing time since fire. Conversely, there was an early or intermediate peak in taller and ‘short dispersal potential’ functional types.
4. We propose that the unusual ‘U’-shaped diversity–time since fire relationship is driven by competitively dominant tree and shrub layers having maximum cover at intermediate times since fire. Subdominant functional types were able to exploit lower levels of competition in the immediate post-fire period and after density-dependent thinning of the trees and shrubs.
5. Synthesis and applications. Recurrent fire is not required to maintain diversity in these fire-sensitive woodlands as diversity reached a maximum in mature vegetation. Fire intervals of <c. 200 years are likely to have adverse consequences on diversity, which is of conservation concern given apparently high recent rates of occurrence of fire. Changes in diversity were not apparent when times since fire were truncated to those available from remote sensing, illustrating that space-for-time studies defined solely by remote sensing may obscure equivalent ‘U’-shaped diversity–time since fire relationships.

1. The primary aim of many agri-environment schemes (AES) is to enhance biodiversity; however, the results of AES designed for this purpose have, to date, been largely underwhelming. One reason for this may be because AES tend to be administered at the farm scale.
2. We argue that collaborative AES (cAES) – single environmental management agreements for multiple farm units – can benefit biodiversity. We then discuss how a shift to this type of scheme may impact upon ecosystem services (ES).
3. Evidence gathered from studies carried out across European farmland demonstrated that more than a third (18 of 52; 35%) of the bird, mammal, reptile, amphibian and bumblebee species important in English farmland operate at scales larger than the typical English farm (146 ha) in the breeding season. While this study relates ranging behaviour specifically to England and the English AES system, the estimates of ranging behaviour presented in this study could also be used (with caution) to compare with farm sizes elsewhere in Europe, making the results of wider geographical relevance.
4. Data were obtained from face-to-face interviews with 32 farmers with differing AES backgrounds [current participants at either low or high level (entry-level Stewardship or higher-level Stewardship/countryside Stewardship scheme), or current non-participants]. Eighty-one per cent of interviewees were found to be willing, in principle, to participate in a collaborative AES (cAES) programme. However, they viewed less extensive options (e.g. management of existing hedgerows) more favourably than extensive or cooperatively demanding land management options (e.g. large-scale habitat creation). Data from an online consultation of a further 122 farmers supported the principal finding, with 75% of respondents willing, in theory, to participate in collaborative schemes.
5. Synthesis and applications. Well-designed landscape-scale schemes are likely to be more beneficial than farm-scale schemes for a small but significant number of key farmland species and ES, such as bats, mammals and some important pollinators, while unlikely to harm species operating at smaller scales. These schemes can be expected to attract widespread participation from landowners. Thus, policymakers may be heartened that collaborative AES are a potential multifaceted solution to environmental management on farmland.

1. Mature urban trees improve air quality, reduce storm water run-off and sequester carbon. Municipal agencies establish forests of native juvenile trees to enhance these and other ecosystem services to cities. Little data exist, however, regarding whether these trees will form mature, native forests.
2. We review urban forestry research that deals specifically with the growth, survival and recruitment of new native urban forests and use these data to identify knowledge gaps and propose research needed to create and maintain native urban forests.
3. Experimental urban forestry studies are few and most are of durations ≤5 years, shorter than the 10–25 year time frame required to understand forest stand dynamics. Studies capturing initial dynamics of urban afforestation (≤5 years) identify invasive species as the primary threat to native tree establishment. Data exploring longer-term dynamics are needed to evaluate whether early-stage afforestation dynamics can be used to infer the composition and function of mature urban forests.
4. Synthesis and applications. Urban afforestation approaches – from natural colonization to large-scale plantings – represent a trade-off in cost vs. efficacy for establishing native forests. A major cost-saving strategy would be to determine whether exotics and natives can co-exist and provide the intended ecosystem services.

1. Understanding the environmental factors that structure biodiversity and food webs among communities is central to assess and mitigate the impact of landscape changes.
2. Wildflower strips are ecological compensation areas established in farmland to increase pollination services and biological control of crop pests and to conserve insect diversity. They are arranged in networks in order to favour high species richness and abundance of the fauna.
3. We describe results from experimental wildflower strips in a fragmented agricultural landscape, comparing the importance of landscape, of spatial arrangement and of vegetation on the diversity and abundance of trap-nesting bees, wasps and their enemies, and the structure of their food webs.
4. The proportion of forest cover close to the wildflower strips and the landscape heterogeneity stood out as the most influential landscape elements, resulting in a more complex trap-nest community with higher abundance and richness of hosts, and with more links between species in the food webs and a higher diversity of interactions. We disentangled the underlying mechanisms for variation in these quantitative food web metrics.
5. We conclude that in order to increase the diversity and abundance of pollinators and biological control agents and to favour a potentially stable community of cavity-nesting hymenoptera in wildflower strips, more investment is needed in the conservation and establishment of forest habitats within agro-ecosystems, as a reservoir of beneficial insect populations.

This paper focuses on the diversity and abundance of trap-nesting bees, wasps and their enemies, and compares the importance of landscape composition, spatial arrangement, and vegetation on the complexity and the structure of their food webs. For the first time, the authors disentangle the underlying mechanisms for variation in quantitative food-web metrics such as vulnerability, generality and compartmentalization. 

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Conservation efforts for threatened or endangered species are challenging because the multi-scale factors that relate to their decline or inhibit their recovery are often unknown. To further exacerbate matters, the perceptions associated with the mechanisms of species decline are often viewed myopically rather than across the entire species range. We used over 80 years of fish presence data collected from the Great Plains and associated ecoregions of the United States, to investigate the relative influence of changing environmental factors on the historic and current truncated distributions of the Arkansas River shiner Notropis girardi. Arkansas River shiner represent a threatened reproductive ecotype considered especially well adapted to the harsh environmental extremes of the Great Plains. Historic (n = 163 records) and current (n = 47 records) species distribution models were constructed using a vector-based approach in MaxEnt by splitting the available data at a time when Arkansas River shiner dramatically declined. Discharge and stream order were significant predictors in both models; however, the shape of the relationship between the predictors and species presence varied between time periods. Drift distance (river fragment length available for ichthyoplankton downstream drift before meeting a barrier) was a more important predictor in the current model and indicated river segments 375–780 km had the highest probability of species presence. Performance for the historic and current models was high (area under the curve; AUC > 0.95); however, forecasting and backcasting to alternative time periods suggested less predictive power. Our results identify fragments that could be considered refuges for endemic plains fish species and we highlight significant environmental factors (e.g., discharge) that could be manipulated to aid recovery.

Crop model-specific biases are a key uncertainty affecting our understanding of climate change impacts to agriculture. There is increasing research focus on intermodel variation, but comparisons between mechanistic (MMs) and empirical models (EMs) are rare despite both being used widely in this field. We combined MMs and EMs to project future (2055) changes in the potential distribution (suitability) and productivity of maize and spring wheat in South Africa under 18 downscaled climate scenarios (9 models run under 2 emissions scenarios). EMs projected larger yield losses or smaller gains than MMs. The EMs’ median-projected maize and wheat yield changes were −3.6% and 6.2%, respectively, compared to 6.5% and 15.2% for the MM. The EM projected a 10% reduction in the potential maize growing area, where the MM projected a 9% gain. Both models showed increases in the potential spring wheat production region (EM = 48%, MM = 20%), but these results were more equivocal because both models (particularly the EM) substantially overestimated the extent of current suitability. The substantial water-use efficiency gains simulated by the MMs under elevated CO₂ accounted for much of the EM−MM difference, but EMs may have more accurately represented crop temperature sensitivities. Our results align with earlier studies showing that EMs may show larger climate change losses than MMs. Crop forecasting efforts should expand to include EM−MM comparisons to provide a fuller picture of crop–climate response uncertainties.

1. Resilience-based approaches are increasingly being called upon to inform ecosystem management, particularly in arid and semi-arid regions. This requires management frameworks that can assess ecosystem dynamics, both within and between alternative states, at relevant time scales.
2. We analysed long-term vegetation records from two representative sites in the North American sagebrush-steppe ecosystem, spanning nine decades, to determine if empirical patterns were consistent with resilience theory, and to determine if cheatgrass Bromus tectorum invasion led to thresholds as currently envisioned by expert-based state-and-transition models (STM). These data span the entire history of cheatgrass invasion at these sites and provide a unique opportunity to assess the impacts of biotic invasion on ecosystem resilience.
3. We used univariate and multivariate statistical tools to identify unique plant communities and document the magnitude, frequency and directionality of community transitions through time. Community transitions were characterized by 37–47% dissimilarity in species composition, they were not evenly distributed through time, their frequency was not correlated with precipitation, and they could not be readily attributed to fire or grazing. Instead, at both sites, the majority of community transitions occurred within an 8–10 year period of increasing cheatgrass density, became infrequent after cheatgrass density peaked, and thereafter transition frequency declined.
4. Greater cheatgrass density, replacement of native species and indication of asymmetry in community transitions suggest that thresholds may have been exceeded in response to cheatgrass invasion at one site (more arid), but not at the other site (less arid). Asymmetry in the direction of community transitions also identified communities that were ‘at-risk’ of cheatgrass invasion, as well as potential restoration pathways for recovery of pre-invasion states.
5. Synthesis and applications. These results illustrate the complexities associated with threshold identification, and indicate that criteria describing the frequency, magnitude, directionality and temporal scale of community transitions may provide greater insight into resilience theory and its application for ecosystem management. These criteria are likely to vary across biogeographic regions that are susceptible to cheatgrass invasion, and necessitate more in-depth assessments of thresholds and alternative states, than currently available.

Species richness and abundance are biodiversity metrics widely used to describe and estimate changes in biodiversity. Studies of marine species richness and abundance typically focus on one, or just a few, taxa. Consequently, it is currently not possible to understand the performance of predictors of species richness and abundance across marine taxa. Using a taxonomically comprehensive dataset of twelve major taxa of flora and fauna from eight phyla sampled from the inter-reef seabed region of the Great Barrier Reef, Australia, we used boosted regression trees to test the performance of fourteen environmental and spatial predictors of species richness and abundance. Sediment composition predicted richness best for all taxa: gravel contributed up to 39% relative influence for one group and all taxa had low richness in muddy habitats. Sea surface temperature, seabed current shear stress, depth and latitude were also influential predictors for species richness for eight groups. Sediment was frequently an influential predictor for abundance also, while distance to domain (reef/coast) and longitude were relatively influential for six taxa. Within-site richness was correlated between nearly all pairs of taxa, as was within-site abundance, however ρ values were low. Overall, model performance was high, explaining up to 62% deviance of species richness, and 38% of abundance. Typically, deviance explained was greater for richness than abundance and may indicate that some drivers of species richness operate independently of any effects on species richness mediated by their effect on abundance. Deviance explained differed most between richness and abundance for bryozoans (23.3% difference) and soft corals (15.2% difference). While sediments were consistently the best predictors across all taxa, the inconsistent influence of all other predictors across taxonomic groups, as well as the low correlation of richness and abundance across taxonomic groups, cautions against predicting regional patterns of species richness and abundance from few taxa.

Temperate and boreal forests are forecast to change in composition and shift spatially in response to climate change. Local-scale expansions and contractions are most likely observable near species range limits, and as trees are long-lived, initial shifts are likely to be detected in the understory regeneration layers. We examined understory relative abundance patterns of naturally regenerated temperate and boreal tree species in two size classes, seedlings and saplings, and across two spatial scales, local stand-scale ecotones (tens of meters) and the regional temperate–boreal transition zone (˜250 km) in central North America, to explore indications of climate-mediated shifts in regeneration performance. We also tested for the presence of strong environmental gradients across local ecotones that might inhibit species expansion. Results showed that tree regeneration patterns across ecotones varied by species and size class, and varied across the regional summer temperature gradient. Temperate tree species regeneration has established across local ecotones into boreal forest patches and this process was facilitated by warmer temperatures. Conversely, boreal conifer regeneration exhibited negative responses to the regional temperature gradient and only displayed high abundance at the boreal end of local ecotones at cool northern sites. The filtering effects of temperature also increased with individual size for both boreal and temperate understory stems. Observed regeneration patterns and the minor environmental gradients measured across local ecotones failed to support the idea that there were strong barriers to potential temperate tree expansion into boreal forest patches. Detectable responses, consistently in the directions predicted for both temperate and boreal species, indicate that summer temperature is likely an important driver of natural tree regeneration in forests across the temperate–boreal transition zone. Regeneration patterns point toward temperate expansion and reduced but continued boreal presence in the near-future, resulting in local and regional expansions of mixed temperate-boreal forests.

Synthesis of ecological and evolutionary concepts and tools has led to improved understanding of how diversification, dispersal, community assembly, long-term coexistence and extinction shape patterns of biological diversity. Phylogeography, with its focus on Quaternary interactions within and between populations, can help elucidate the processes acting between the evolutionary time-scales on which species arise and the ecological time-scales on which members of an assemblage interact with each other and their environment. Still, it has yet to be widely incorporated in that synthesis. Here, we highlight three areas where integration of phylogeography with ecological and evolutionary approaches can provide new insights into key questions. First, phylogeography can help clarify the roles of isolation, niche conservatism and environmental stability in generating patterns of alpha- and beta-diversity. Second, phylogeography can help isolate the effects of Quaternary dispersal limitation from other factors driving community assembly and spatial turnover. Third, phylogeography can help identify key processes leading to and resulting from extinction events, including the population dynamics of species range reduction and its effects on the strength and temporal flexibility of networks of species interactions. We conclude with an outlook on the data-gathering protocols necessary for this collaborative, interdisciplinary research agenda.

1. Woodfuel extraction from established woods and forests is promoted in Western Europe as a renewable energy source. Woodfuel management is mainly carried out by silvicultural thinning or short-rotation harvesting, including coppicing. Potential negative effects include reduction in habitat quality for saproxylic species. However, in some regions, habitats may be improved for species that have declined as a result of increased shading. Resources required by most of these species are more likely to be delivered by short-rotation management than thinning.
2. Relatively little is documented on the effects of thinning intensity on ecological resources and biodiversity within European forests. Trade-offs between canopy cover, deer browsing pressure and understorey complexity are likely to occur. Therefore, interactions between thinning treatments and deer browsing potentially affect biodiversity, in the context of both woodfuel and timber production.
3. Synthesis and applications. Woodfuel management is unlikely to deliver benefits for most shade-intolerant species unless it creates substantial areas of young-growth with low deer impacts. However, more research is needed on thinning as a potential conservation tool. Changing climate and tree diseases are creating an uncertain future for forest management. It is timely for ecologists to work with forest managers to identify how integrated forestry and deer management can deliver positive and balanced biodiversity outcomes.

1. Rapid environmental change is placing increasing pressure on the survival of many species globally. Ecological refuges can mitigate the impacts of change by facilitating the survival or persistence of organisms in the face of disturbance events that would otherwise lead to their mortality, displacement or extinction. Refuges may have a critical influence on the successional trajectory and resilience of ecosystems, yet their function remains poorly understood.
2. We review and describe the role of refuges in faunal conservation in the context of fire, a globally important disturbance process.
3. Refuges have three main functions in relation to fire: they enhance immediate survival during a fire event, facilitate the persistence of individuals and populations after fire and assist in the re-establishment of populations in the longer term. Refuges may be of natural or anthropogenic origin, and in each case, their creation can arise from deterministic or stochastic processes. The specific attributes of refuges that determine their value are poorly known, but include within-patch attributes relating to vegetation composition and structure; patch-scale attributes associated with their size and shape; and the landscape context and spatial arrangement of the refuge in relation to fire patterns and land uses.
4. Synthesis and applications. Refuges are potentially of great importance in buffering the effects of wildfire on fauna. There is an urgent need for empirical data from a range of ecosystems to better understand what constitutes a refuge for different taxa, the spatial and temporal dynamics of species' use of refuges and the attributes that most influence their value to fauna. Complementary research is also required to evaluate threats to naturally occurring refuges and the potential for management actions to protect, create and enhance refuges. Knowledge of the spatial arrangement of refuges that enhance the persistence of fire-sensitive species will aid in making decisions concerning land and fire management in conservation reserves and large natural areas. Global change in the magnitude and extent of fire regimes means that refuges are likely to be increasingly important for the conservation of biodiversity in fire-prone environments.

1. Because many large mammal species have wide geographical ranges, spatially distant populations may be confronted with different sets of environmental conditions. Investigating how home range (HR) size varies across environmental gradients should yield a better understanding of the factors affecting large mammal ecology.
2. We evaluated how HR size of a large herbivore, the roe deer (Capreolus capreolus), varies in relation to seasonality, latitude (climate), weather, plant productivity and landscape features across its geographical range in Western Europe. As roe deer are income breeders, expected to adjust HR size continuously to temporal variation in food resources and energetic requirements, our baseline prediction was for HR size to decrease with proxies of resource availability.
3. We used GPS locations of roe deer collected from seven study sites (EURODEER collaborative project) to estimate fixed-kernel HR size at weekly and monthly temporal scales. We performed an unusually comprehensive analysis of variation in HR size among and within populations over time across the geographical range of a single species using generalized additive mixed models and linear mixed models, respectively.
4. Among populations, HR size decreased with increasing values for proxies of forage abundance, but increased with increases in seasonality, stochastic variation of temperature, latitude and snow cover. Within populations, roe deer HR size varied over time in relation to seasonality and proxies of forage abundance in a consistent way across the seven populations. Thus, our findings were broadly consistent across the distributional range of this species, demonstrating a strong and ubiquitous link between the amplitude and timing of environmental seasonality and HR size at the continental scale.
5. Overall, the variability in average HR size of roe deer across Europe reflects the interaction among local weather, climate and seasonality, providing valuable insight into the limiting factors affecting this large herbivore under contrasting conditions. The complexity of the relationships suggests that predicting ranging behaviour of large herbivores in relation to current and future climate change will require detailed knowledge not only about predicted increases in temperature, but also how this interacts with factors such as day length and climate predictability.

This paper presents the first pan-European study of the biogeography of home range size in a large herbivore based on GPS locations in seven study sites across Europe. The findings are broadly consistent across the distributional range of this species, demonstrating a strong and ubiquitous link between the amplitude and timing of environmental seasonality and home range size at the continental scale.

1. The timing of bird migration has shifted in response to climate change. However, few studies have linked the potential consequences of any phenological shift on individual fitness and even fewer have disentangled the role of plasticity and microevolution in the observed shifts.
2. The arrival date and breeding success of white storks (Ciconia ciconia) have been recorded since the 1880s in Slovakia. We used data for two periods (1895–1913 and 1977–2007), which were considered, respectively, as populations before and after the start of climate warming. About 4000 male and 2500 female arrival dates along with 3000 breeding attempts were studied.
3. Mean arrival dates did not differ between the two periods. During 1977–2007, males tended towards a slight delay for most fractions of arrival distribution. Protandry was reduced by 30% (1·44 days).
4. In both sexes, the early percentiles of the arrival distribution arrived later those years with warmer temperatures at the African wintering grounds, while late percentiles advanced their arrival when temperatures were higher in the European areas flown over during migration.
5. Mean breeding success of the Slovakian population has not changed since 1977. However, fecundity selection for arrival date reduced over the years: at the end of 1970s and 1980s, early breeders had more success than late breeders, but this seasonal trend disappeared towards the end of the study period. An early arrival and territory acquisition may have become less of an advantage due to the enhancement of feeding opportunities during the breeding season in recent decades.
6. A century ago, stork arrival varied spatially, with earlier arrivals at low altitudes, southern slopes and warmer and drier regions. This spatial variation mostly vanished, and at present, we found little correlations with topographical and climatic gradients.
7. We showed that long-term temporal changes in the timing of biological events may be complex because each fraction of a population and sex may show different temporal trends in their arrival dates. In addition, the effect of biotic and abiotic factors may change consistently in space and time, and thereby phenotypes' value depends on the circumstances that are expressed due to its variable fitness consequences.

Using a very long-term, large-scale dataset of the migratory phenology of one of the most cherished European birds, the white stork, the authors provide new insights into the plastic and microevolutionary responses of migratory birds to climate change. Phenological changes and their long-term dynamics are shown to be much more complex than previously thought.

1. National and international assessments are increasingly highlighting the unsustainable use of earth's natural resources in the face of population increase, growing material affluence and global change. In all likelihood, the use and degradation of natural resources will continue.
2. In contrast to resource depletion, the concept of natural capital emphasises how the environment is an asset to be managed, to ensure that the benefits which flow from it are sustained for future generations. These benefits are the ecosystem goods and services upon which all people rely for their continued survival and well-being both now and, ideally, in perpetuity.
3. Despite their importance, the evidence-base and quantitative understanding of links between biodiversity, ecosystem function and ecosystem services are insufficient to allow informed use and management. Moreover, the concepts of natural capital and ecosystem services are insufficiently mainstream to influence decisions that currently favour the production of food and fibre rather than less tangible services such as climate regulation, air and water purification, pollination or the contributions of environment to health.
4. There are specific challenges to ecological science in this interdisciplinary endeavour: specifically, to develop frameworks for identifying and monitoring natural capital; to parameterise factors affecting ecosystem services and their resilience to change; to integrate the complexity of ecological systems into ecosystem service valuation; and to characterise the synergies and trade-offs between ecosystem services in different management and policy scenarios.
5. Synthesis and applications. The five papers in this Special Profile exemplify just some of the leading work through which ecologists in the UK are contributing nationally and internationally to these needs, stemming from the UK National Ecosystem Assessment - the first national scale exercise of its type in the world. We expect a major, worldwide increase in work on ecosystem services and natural capital in future as decisions on ecosystem use of management are squeezed increasingly between the needs of exploitation and protection.

1. Quantifying wildlife-habitat relationships through resource selection analysis (RSA) has traditionally relied on landscape variables extracted at medium-to-coarse scales and general-purpose digital maps. However, RSA at fine scales, facilitated by accurate positional data obtained using GPS-tags, requires improved measures of habitat resources. The combination of cutting-edge remote sensing technology, such as very high spatial resolution (VHSR) satellite imagery and object-based image analysis (OBIA), can provide landscape maps that are suitable for the extraction of detailed variables at fine scale.

2. We used Quickbird satellite imagery and OBIA to produce a map using the multispectral bands (MULT), and explored the usefulness of the technique for resource identification by combining the panchromatic (highest spatial resolution) and multispectral (spectral information) bands (PAN:MULT) to produce a second map. Each of the mapping methods was used in a heterogeneous braided-river environment in New Zealand to: (1) classify and delimit ground features using an object-based accuracy assessment approach; (2) detect ground features of different sizes; (3) extract independent landscape variables at fine scale (within buffers between 20 and 30 m) for separate RSA for introduced hedgehogs (Erinaceus europaeus) and feral cats (Felis catus).

3. Per-pixel accuracy assessment produced overall accuracies of 82% (PAN:MULT) and 79% (MULT). The per-object assessment using shrubs as the testing class yielded further information on classification and delimitation of object accuracy, with accuracies of 80% for shrub patches ≥30 m² in MULT and ≥5 m² in PAN:MULT. The inclusion of the panchromatic band noticeably improved the identification and delimitation of cover. However, RSA using each of the maps did not yield differences in the best models for cats or hedgehogs.

4. VHSR imagery and OBIA provide a valuable method to identify smaller ground features and thus to produce more detailed landscape maps to study animal habitat use at fine scale. Improvements in ground feature detection achieved by including the panchromatic band may not justify its cost, as it was shown for the studies on cats and hedgehogs presented here. However, the level of detail offered by the panchromatic layer may be useful for addressing other RSA questions or applications at fine scale, such as remote censusing of colonial species.