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Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

How can we tell if the ecosystem services upon which we rely are at risk of being lost, potentially permanently? Ecosystem services underpin human well-being, but we lack a consistent approach for categorizing the extent to which they are threatened. We present an assessment framework for assessing the degree to which the adequate and sustainable provision of a given ecosystem service is threatened. Our framework combines information on the states and trends of both ecosystem service supply and demand, with reference to two critical thresholds: demand exceeding supply and ecosystem service ‘extinction’. This framework can provide a basis for global, national, and regional assessments of threat to ecosystem services, and accompany existing assessments of threat to species and ecosystems. [ABSTRACT FROM AUTHOR]

Context: Native vegetation extent is often a proxy for habitat area in studies of human-modified landscapes. However, the loss and retention of native vegetation is rarely random among landscapes. Instead, the extent of native vegetation in landscapes may be correlated with abiotic factors, thereby obscuring or distorting relationships between ecological phenomena and area. Objectives: We asked: (1) how has the potential for non-random vegetation loss to confound area effects been addressed in the landscape ecology literature? (2) Are consistent patterns of non-random vegetation loss and retention evident from modified regions of two countries? Methods: We reviewed 118 papers that related area to an ecological response, to determine whether potential biases associated with non-random vegetation loss and retention were considered. We then analysed ~18,000 100 km landscape units in Australia and South Africa to identify how different abiotic factors correlate with the extent of native vegetation retained in those landscapes. Results: Only 21% of the studies we reviewed explicitly or implicitly considered spatial biases in vegetation clearing. Yet, across modified regions of Australia and South Africa, landscape-scale native vegetation extent was consistently and often strongly related to abiotic factors, particularly soil properties and topographic variability. Conclusion: Patterns of vegetation clearing and retention commonly reflect underlying abiotic heterogeneity. These biases, which are infrequently highlighted in studies focussing on area effects, have implications for how we assess the importance of vegetation extent for species and assemblages. Failure to account for correlates of vegetation extent risks erroneous area-based conservation prescriptions in human-modified environments. [ABSTRACT FROM AUTHOR]

Biodiversity conservation policies incorporating a no net loss ( NNL) principle are being implemented in many countries. However, there are linguistic and conceptual inconsistencies in the use of terms underlying these NNL policies., We identify inconsistencies that emerge in the usage of eight key terms and phrases associated with NNL policies: biodiversity, frames of reference (i.e. baselines, counterfactuals), no net loss, mitigation hierarchy, biodiversity offset, in-kind/out-of-kind, direct/indirect and multipliers., For each term, we make recommendations to support conceptual convergence, reduce ambiguity and improve clarity in communication and policy documentation. However, we also warn of the challenges in achieving convergence, especially given the linguistic inconsistencies in several of these key concepts among countries in which NNL policies are employed., Policy implications. The recommendations made in this article, on improving clarity and supporting convergence on key no net loss ( NNL) concepts, should help eliminate ambiguity in policy documentation. This is crucial if policymakers are to design robust policies that are (i) transparent, (ii) translatable into practice in a consistent manner and (iii) sufficiently understood and supported by stakeholders to be effective in practice. [ABSTRACT FROM AUTHOR]

Vegetation vertical structure is important for biodiversity and ecosystem service provision. In cities, however, while variation in the spatial extent and distribution of vegetation has been widely investigated, vertical vegetation structure and its potential drivers have not. Understanding how vegetation vertical structure varies across cities and identifying the potential drivers of this variation will improve the management of urban vegetation for biodiversity and ecosystem services., We used light detection and ranging (Li DAR) data to quantify the vertical structure of vegetation across Brisbane, Australia, at 1-km2 and 1-ha spatial scales and investigated how this structure varied in response to biophysical, socioeconomic, urban form and landscape structure variables., Using model selection techniques, we found that landscape structure variables related to tree cover (tree cover extent and spatial configuration) best explained the vegetation vertical structure at both spatial scales. Biophysical and urban form variables were also important, but only in combination with landscape structure., Mean vegetation vertical complexity, foliage projective cover and canopy height at a site all decreased as the treed proportion of the surrounding urban landscape decreased. In general, these vertical structure variables also increased where patches of vegetation were clustered together spatially., Synthesis and applications. Using light detection and ranging (Li DAR) data and model selection techniques, we show that the extent and vertical structure of urban vegetation are not independent and that reduced extent and increased fragmentation of urban vegetation are associated with simplification of its vertical structure. If common, this relationship means that managing urban vegetation for biodiversity and ecosystem services should not focus solely on the amount of tree cover or green space present across cities, but also on identifying where interventions to improve vegetation vertical complexity are required. Our study provides important insights into where these locations may be in cities. [ABSTRACT FROM AUTHOR]

Offsetting is a policy instrument intended to provide flexibility for development. We developed a simple calculator to predict when no net loss is feasible using biodiversity offsetting. Assuming offset ratios ≤10:1 are indicative of operational feasibility and employing a discount rate of 3%, we predicted that no net loss is feasible where biodiversity can be restored within 55 years, which restricts the impacts on biodiversity that can be offset using restoration. Alternatively, no net loss is feasible by avoiding loss to biodiversity that is declining under the counterfactual at an annual rate ≥6%. However, this is considerably higher than typical background rates of biodiversity loss so restricts where avoided-loss offsets are feasible. No net loss is theoretically feasible in the broadest range of circumstances if biodiversity gains are provided in advance of development. However, these gains are procured by restoration or avoided loss, so constraints presented by these approaches also apply. We concluded that no net loss is feasible in a limited range of development scenarios unless offset ratios greater than 10:1 are more widely tolerated. [ABSTRACT FROM AUTHOR]

The rising popularity of biodiversity offsetting as a tool for balancing biodiversity losses from development with equivalent gains elsewhere has sparked debate on many fronts. The fundamental questions are the following: Is offsetting good, bad, or at least better than the status quo for biodiversity conservation outcomes, and what do we need to know to decide? We present a concise synthesis of the most contentious issues related to biodiversity offsetting, categorized as ethical, social, technical, or governance challenges. In each case, we discuss avenues for reducing disagreement over these issues and identify those that are likely to remain unresolved. We argue that there are many risks associated with the unscrutinized expansion of offset policy. Nevertheless, governments are increasingly adopting offset policies, so working rapidly to clarify and-- where possible--to resolve these issues is essential. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Context: An increasing number of studies have investigated the impact of environmental heterogeneity on faunal assemblages when measured at multiple spatial scales. Few studies, however, have considered how the effects of heterogeneity on fauna vary with the spatial scale at which the response variable is characterised. Objectives: We investigated the relationship between landscape properties in a region characterised by diverse fire mosaics, and the structure and composition of avian assemblages measured at both the site- (1 ha) and landscape-scale (100 ha). Methods: We surveyed birds and calculated spatial landscape properties in sub-tropical woodlands of central Queensland, Australia. Results: Environmental heterogeneity, as measured by topographic complexity, was consistently important for bird species richness and composition. However, the explanatory power of topographic complexity varied depending on the spatial scale and the component of diversity under investigation. We found different correlates of richness within particular foraging guilds depending on the scale at which richness was measured. Extent of long-unburnt habitat (>10 years since fire) was the most important variable for the landscape-scale richness of frugivores, insectivores and canopy feeders, whereas environmental heterogeneity in the surrounding landscape was more important for site-scale richness of these foraging guilds. Conclusions: The response of species richness to landscape characteristics varies among scales, and among components of diversity. Thus, depending on the scale at which a biodiversity conservation goal is conceptualised-maximising richness at a site, or across a landscape-different landscape management approaches may be preferred. [ABSTRACT FROM AUTHOR]

Ecological restoration of modified and degraded landscapes is an important challenge for the 21st century, with potential for major gains in the recovery of biodiversity. However, there is a general lack of agreement between plant- and animal-based approaches to restoration, both in theory and practice. Here, we review these approaches, identify limitations from failing to effectively integrate their different perspectives, and suggest ways to improve outcomes for biodiversity recovery in agricultural landscapes. We highlight the need to strengthen collaboration between plant and animal ecologists, to overcome disciplinary and cultural differences, and to achieve a more unified approach to restoration ecology. Explicit consideration of key ecosystem functions, the need to plan at multiple spatial and temporal scales, and the importance of plant-animal interactions can provide a bridge between plant- and animal-based methods. A systematic approach to restoration planning is critical to achieving effective biodiversity outcomes while meeting long-term social and economic needs. [ABSTRACT FROM AUTHOR]

Interactions between environmental factors can dramatically influence the relationships between a species and its environment. However, multiple types of interaction are possible, and as such, some may be overlooked. We used a Bayesian network to model the response of a riparian tree species, Eucalyptus camaldulensis Dehnh., to the interactive influences of hydrological factors. We used a novel conceptual framework, which included not only synergistic and antagonistic interactions but also qualitative interactions (i.e. the effect of an environmental factor that switches from positive to negative or vice versa depending on the value of another factor). Synergistic, antagonistic and qualitative interactions were all detected in the response of E. camaldulensis to hydrological factor interactions. The predicted influence of environmental factors varied dramatically when interactions were considered. In some instances, the likelihood of a certain outcome differed by greater than 80% when interactions were considered. For example, the negative impact of grazing on E. camaldulensis was far greater in areas of deep groundwater relative to areas of shallow groundwater. Interactions also led to qualitatively different predictions (i.e. a qualitative interaction occurred). For example, frequent wetland inundation had a positive influence on tree vigour in wetlands minimally impacted by weirs, but a negative influence in wetlands close to weirs. Considering interactions may therefore substantially change understanding of ecohydrological relationships. Thinking of interactions between factors as potentially qualitative, and not only as synergistic and antagonistic, is likely to be important in situations where multiple management interventions are proposed. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]