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The primary focus of many in-stream restoration projects is to enhance habitat diversity for salmonid fishes, yet the lack of properly designed monitoring studies, particularly ones with pre-restoration data, limits any attempts to assess whether restoration has succeeded in improving salmonid habitat. Even less is known about the impacts of fisheries-related restoration on other, non-target biota. We examined how restoration aiming at the enhancement of juvenile brown trout (Salmo trutta L.) affects benthic macroinvertebrates, using two separate data sets: (1) a before-after-control-impact (BACI) design with three years before and three after restoration in differently restored and control reaches of six streams; and (2) a space-time substitution design including channelized, restored, and near-natural streams with an almost 20-year perspective on the recovery of invertebrate communities. In the BACI design, total macroinvertebrate density differed significantly from before to after restoration. Following restoration, densities decreased in all treatments, but less so in the controls than in restored sections. Taxonomic richness also decreased from before to after restoration, but this happened similarly in all treatments. In the long-term comparative study, macroinvertebrate species richness showed no difference between the channel types. Community composition differed significantly between the restored and natural streams, but not between restored and channelized streams. Overall, the in-stream restoration measures used increased stream habitat diversity but did not enhance benthic biodiversity. While many macroinvertebrates may be dispersal limited, our study sites should not have been too distant to reach within almost two decades. A key explanation for the weak responses by macroinvertebrate communities may have been historical. When Fennoscandian streams were channelized for log floating, the loss of habitat heterogeneity was only partial. Therefore, habitat may not have been limiting the macroinvertebrate communities to begin with. Stream restoration to support trout fisheries has strong public acceptance in Finland and will likely continue to increase in the near future. Therefore, more effort should be placed on assessing restoration success from a biodiversity perspective using multiple organism groups in both stream and riparian ecosystems.  相似文献   
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Planning for adaptation to climate change is often regarded to be a local imperative and considered to be more effective if grounded on a solid evidence base and recognisant of relevant climate projections. Research has already documented some of the challenges of making climate information usable in decision-making but has not yet sufficiently reflected on the role of the wider institutional and regulatory context. This article examines the impact of the external institutional context on the use and usability of climate projections in local government through an analysis of 44 planning and climate change (adaptation) documents and 54 semi-structured interviews with planners in England and Germany conducted between July 2013 and May 2014. We show that there is little demand for climate projections in local adaptation planning in either country due to existing policy, legal and regulatory frameworks. Local government in England has not only experienced a decline in use of climate projections, but also the waning of the climate change adaptation agenda more widely, amidst changes in the planning and regulatory framework and severe budget cuts. In Germany, spatial planning makes substantial use of past and present climate data, but the strictly regulated nature of planning prevents the use of climate projections, due to their inherent uncertainties. Findings from the two countries highlight that if we are to better understand the usability of climate projections, we need to be more aware of the institutional context within which planning decisions are made. Otherwise we run the risk of continuing to provide tools and information that are of limited use within their intended context.  相似文献   
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Anaerobic digestion of autoclaved (160 °C, 6.2 bar) and untreated source segregated food waste (FW) was compared over 473 days in semi-continuously fed mesophilic reactors with trace elements supplementation, at organic loading rates (OLRs) of 2, 3, 4 and 6 kg volatile solids (VS)/m3 d. Methane yields at all OLR were 5–10% higher for untreated FW (maximum 0.483 ± 0.013 m3 CH4/kg VS at 3 kg VS/m3 d) than autoclaved FW (maximum 0.439 ± 0.020 m3 CH4/kg VS at 4 kg VS/m3 d). The residual methane potential of both digestates at all OLRs was less than 0.110 m3 CH4/kg VS, indicating efficient methanation in all cases. Use of acclimated inoculum allowed very rapid increases in OLR. Reactors fed on autoclaved FW showed lower ammonium and hydrogen sulphide concentrations, probably due to reduced protein hydrolysis as a result of formation of Maillard compounds. In the current study this reduced biodegradability appears to outweigh any benefit due to thermal hydrolysis of ligno-cellulosic components.  相似文献   
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Systematic understanding of adaptation measures utilised by households in developing countries is needed to identify the constraints they face, and the external interventions or adaptation planning needed to overcome them. Understanding of autonomous household adaptation patterns remains underdeveloped. In particular, little is known regarding whether households are implementing incremental or transformational adaptation measures as well as the implications of this for adaptation planning. We demonstrate the suitability of the risk hazard approach for understanding autonomous household adaptation patterns and discuss the implications for planned adaptation. To achieve this, we use an in-depth village case study from an area of Bangladesh particularly vulnerable to climate change, using qualitative semi-structured household interviews as primary material. We find that the risk hazard approach is ideal for exploring autonomous adaptations because of its capacity for understanding how households respond to livelihood risk, and what resources are required for it to be most effective. However, the risk hazard approach overlooks equity and fairness considerations need to be integrated due to the insufficient emphasis on these concerns.

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Sustainable development as the leading global development paradigm and sustainability as a cornerstone of modern industrial development have guided this development work on social metrics in the process industry. This study addresses the development of social metrics in the process industry and for metal production, in particular, at the plant level. The developed social indicators are one part of the overall sustainability index that aims to present a balanced and holistic view of plant-level sustainability performance, encompassing information on all different dimensions. This development work was preceded by the benchmarking and review of existing global reporting frameworks, initiatives and the literature. Current indicators of industrial sustainability mainly satisfy the needs of corporate-level management and capital investors. Therefore, plant-level indicators are critically needed to support and fill potential gaps in corporate-level assessments and management with a special emphasis on plant-level sustainability. The purpose of our development work for social indicators was to operationalise the concept of sustainability and associated performance measurement at the plant level. The development of social indicators was carried out through workshops with industry partners. As a joint effort, eight core social indicators and their associated sub-indicators were developed. We also report the results of our benchmarking and review of existing frameworks, initiatives and the literature. The social part of the overall sustainability index provides the information on both in-plant sustainability performance and the direct and indirect impacts of plant-level operations on the surrounding society including various stakeholders, interest groups and citizens.  相似文献   
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Owing to the lack of information about the distribution patterns of many taxonomic groups, biodiversity conservation strategies commonly rely on a surrogate taxa approach for identifying areas of maximum conservation potential. Macroinvertebrates or fish are the most likely candidates for such a role in many freshwater systems. The usefulness of the surrogate taxa depends largely on community concordance, i.e., the degree of similarity in community patterns among taxonomic groups across a set of sites. We examined the effect of the spatial scale of a. study on the strength of community concordance among macroinvertebrates, bryophytes, and fish by comparing the concordance between ordinations of these groups in 101 boreal stream sites. We specifically asked if communities spanning several drainages are more concordant than those originating from a single drainage system. Our results indicate that community concordance is affected by spatial extent, being variable and generally weak at the scale of individual drainages, but strong across multiple drainage systems and ecoregions. We attribute this finding to different taxonomic groups responding to similar environmental factors and sharing a similar latitudinal gradient of community structure when viewed across large spatial scales. We also identified a "gradient of concordance," with sites contributing disproportionately to community concordance being in relatively large streams with high microhabitat variability. Overall, our results suggest that the degree of community concordance among freshwater organism groups depends critically on the spatial extent of the study, and surrogate groups at the scale of single river systems should be used with caution.  相似文献   
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