Terrestrial isopod community as indicator of succession in a peat bog

Terrestrial isopods were studied in the Dubravica peat bog and surrounding forest in the northwestern Croatia. Sampling was conducted using pitfall traps over a two year period. Studied peat bog has a history of drastically decrease in area during the last five decades mainly due to the process of natural succession and changes in the water level. A total of 389 isopod individuals belonging to 8 species were captured. Species richness did not significantly differ between bog, edge and surrounding forest. High species richness at the bog is most likely the result of progressive vegetation succession, small size of the bog and interspecific relationships, such as predation. With spreading of Molinia grass on the peat bog, upper layers of Sphagnum mosses become less humid and probably more suitable for forest species that slowly colonise bog area. The highest diversity was found at the edge mainly due to the edge effect and seasonal immigration, but also possibly due to high abundance and predator pressure of the Myrmica ants and lycosid spiders at the bog site. The most abundant species were Trachelipus rathkii and Protracheoniscus politus, in the bog area and in the forest, respectively. Bog specific species were not recorded and the majority of the species collected belong to the group of tyrphoneutral species. However, Hyloniscus adonis could be considered as a tyrphoxenous species regarding its habitat preferences. Most of collected isopod species are widespread eurytopic species that usually inhabit various habitats and therefore indicate negative successive changes or degradation processes in the peat bog.     

Depression screening as a quality indicator

Objective Although practice guidelines for depression screening are evidence based, with their development relying on reviews of controlled studies, their adaptation and use as quality indicators have not been subject to rigorous study. This paper will therefore review the evidence supporting this practice.Methods A rational evaluation was carried out on both controlled studies and other sources of evidence related to the technical, clinical and policy assumptions underlying the use of depression screening guidelines as quality indicators.Results 1) Technical assumptions: depression screening could be used as a quality indicator. Current information technology does not allow accurate determination of who would benefit from being screened, whether they actually were screened, or the optimal percentage that should be screened. 2) Clinical assumptions: depression screening would improve outcomes. The evidence suggests that although depression screening might increase the diagnosis of depression, depressed patients so recognised tend to be less ill, less in need of treatment, or less likely to benefit from treatment, while screening, in the absence of other interventions, does not improve outcomes. 3) Policy assumptions: depression screening should be a focus of quality improvement. However, relative to other preventative measures, depression screening is a low priority. It does not meet usual cost-effectiveness criteria. There are more robust interventions for depression (i.e. collaborative care) that could be a focus of quality improvement efforts.Conclusion Although routine depression screening may be an acceptable practice guideline, its use as a quality measure is not supported.     

White Fringed Orchid as indicator of Sphagnum bog integrity

Ecosystem integrity often needs to be evaluated rapidly; indicator species may be used to do so. In this study we aim to evaluate whether White Fringed Orchid is an indicator of ombrotrophic peatland (Sphagnum bog) integrity in northeastern North America. The study was carried out in 113 sampling plots located in 60 bogs of southern Quebec, Canada. Vegetation (species cover and strata) and abiotic variables were collected within the plots and disturbance variables were determined using aerial photographs and satellite imagery. The level of integrity on each plot was assessed by calculating a Floristic Quality Assessment Index (FQAI) and an Anthropogenic Activity Index (AAI). Data were analyzed with ANOVAs, multivariate techniques and logistic multiple regression. Results indicated that the presence and abundance of White Fringed Orchid were positively linked to the FQAI and negatively to the perimeter/area ratio variable, suggesting that this species is most abundant and frequent at sites that are less disturbed and influenced by human activities. ANOVA showed that the AAI was lower in plots with high orchid abundance than in those without, suggesting that the orchid grows in more pristine sites. Our study showed that White Fringed Orchid abundance and presence may be used to rapidly and accurately evaluate Sphagnum bog integrity.     

High abundance of planctomycetes in anoxic layers of a Sphagnum peat bog

The depth distribution of planctomycete abundance has been examined in six different sites of the Sphagnum peat bog Bakchar, Tomsk oblast, Russia. In situ hybridization of peat with the fluorescently labeled oligonucleotide probes PLA46 and PLA886, reported to be group-specific for representatives of the phylum Planctomycetes, revealed two distinct population maxima of these bacteria in all of the profiles examined. The first population maximum was detected in the uppermost, oxic layer of the bog profile, while the second maximum was located at a depth of 30 cm below the water table level. The population sizes of planctomycetes in the uppermost layer and at a depth of 30 cm were of the same order of magnitude and comprised 0.5–1.5 × 10⁷ and 0.4?0.7 × 10⁷ cells per g^?1 of wet peat, respectively. Only 25–30% of the total number of planctomycete cells in the anoxic layer could be detected if the probe PLA886, whose target specificity is restricted to taxonomically characterized aerobic planctomycetes of the genera Gemmata, Planctomyces, Pirellula, and Isosphaera, was used alone. Other planctomycete cells in this layer were detected only with the probe PLA46, which possesses a much wider scope. This suggests the affiliation of these organisms with a yet undescribed phylogenetic subgroup within the Planctomycetes.     

Bayesian Belief Networks as a tool for evidence-based conservation management

Effective conservation management is dependent on accessing and integrating different forms of evidence regarding the potential impacts of management interventions. Here, we explore the application of Bayesian Belief Networks (BBN), which are graphical models that incorporate probabilistic relationships among variables of interest, to evidence-based conservation management. We consider four case studies, namely: (i) impacts of deer grazing on saltmarsh vegetation; (ii) impacts of burning on upland bog vegetation; (iii) control of the invasive exotic plant Rhododendron ponticum; and (iv) management of lowland heathland by burning. Each of these themes is currently a significant conservation issue in the UK, and yet the potential outcomes of management interventions are poorly understood. Through these examples, we demonstrate that BBNs can be used to integrate and explore evidence from a variety of sources, including expert opinion and quantitative results from research investigations. Incorporation of such information in BBNs enables different sources of evidence to be compared, the potential impacts of management interventions to be explored and management trade-offs to be identified. BBNs also offer a highly visual tool for communicating the uncertainty associated with potential management outcomes to conservation practitioners, and they can also be readily updated as new evidence becomes available. Based on these features, we suggest that BBNs have outstanding potential for supporting evidence-based approaches to conservation management.     

DNA barcoding as a tool for coral reef conservation

DNA Barcoding (DBC) is a method for taxonomic identification of animals that is based entirely on the 5′ portion of the mitochondrial gene, cytochrome oxidase subunit I (COI-5). It can be especially useful for identification of larval forms or incomplete specimens lacking diagnostic morphological characters. DBC can also facilitate the discovery of species and in defining “molecular taxonomic units” in problematic groups. However, DBC is not a panacea for coral reef taxonomy. In two of the most ecologically important groups on coral reefs, the Anthozoa and Porifera, COI-5 sequences have diverged too little to be diagnostic for all species. Other problems for DBC include paraphyly in mitochondrial gene trees and lack of differentiation between hybrids and their maternal ancestors. DBC also depends on the availability of databases of COI-5 sequences, which are still in early stages of development. A global effort to barcode all fish species has demonstrated the importance of large-scale coordination and is yielding promising results. Whether or not COI-5 by itself is sufficient for species assignments has become a contentious question; it is generally advantageous to use sequences from multiple loci.     

The efficiency of indicator groups for the conservation of amphibians in the Brazilian Atlantic Forest

The adequate selection of indicator groups of biodiversity is an important aspect of the systematic conservation planning. However, these assessments differ in the spatial scales, in the methods used and in the groups considered to accomplish this task, which generally produces contradictory results. The quantification of the spatial congruence between species richness and complementarity among different taxonomic groups is a fundamental step to identify potential indicator groups. Using a constructive approach, the main purposes of this study were to evaluate the performance and efficiency of eight potential indicator groups representing amphibian diversity in the Brazilian Atlantic Forest. Data on the geographic range of amphibian species that occur in the Brazilian Atlantic Forest were overlapped to the full geographic extent of the biome, which was divided into a regular equal‐area grid. Optimization routines based on the concept of complementarily were applied to verify the performance of each indicator group selected in relation to the representativeness of the amphibians in the Brazilian Atlantic Forest as a whole, which were solved by the algorithm “simulated annealing,” through the use of the software MARXAN. Some indicator groups were substantially more effective than others in regard to the representation of the taxonomic groups assessed, which was confirmed by the high significance of the data (F = 312.76; P < 0.01). Leiuperidae was considered as the best indicator group among the families analyzed, as it showed a good performance, representing 71% of amphibian species in the Brazilian Atlantic Forest (i.e., 290 species), which may be associated with the diffuse geographic distribution of their species. In this sense, this study promotes understanding of how the diversity standards of amphibians can be informative for systematic conservation planning on a regional scale.     

Assessing the mechanisms behind successful surrogates for biodiversity in conservation planning

Limited by the availability of data, conservation planners must use surrogates for biodiversity when selecting conservation areas. Although several methods have been proposed for selecting surrogates, no clear set of species attributes have been described that allow for the efficient a priori selection of surrogate groups. We used a database of 1449 species in two regions of the United States to (1) examine the consistency in the performance of simple taxonomic-based surrogates of biodiversity and (2) test five hypotheses proposed to explain surrogate performance. First, we compared the ability of sites selected to protect members of seven surrogate groups to protect non-surrogate species in the north-western United States and in the Middle-Atlantic region of the eastern United States. Then, in a separate analysis, we tested whether surrogate performance could be explained by (1) taxonomic diversity; (2) nested species distributions; (3) hotspots of biodiversity; (4) species range sizes; (5) environmental diversity. Our first analysis revealed little consistency in the performance of surrogates in the two different study regions. For example, butterflies provided protection for 76% of all other species in the north-western United States but only 56% of all other species in the eastern United States. Our second analysis revealed only weak associations between species characteristics and surrogate performance. Furthermore, these associations proved inadequate for selecting successful surrogates across study regions. Overall, our results suggest that in lieu of searching for optimal surrogate groups, research efforts will be better spent by developing alternative methods for assessing conservation value in areas where data on species distributions are limited.     

The use of indicator taxa as representatives of communities in bioassessment

1. Sampling and processing of benthic macroinvertebrate samples is time consuming and expensive. Although a number of cost‐cutting options exist, a frequently asked question is how representative a subset of data is of the whole community, in particular in areas where habitat diversity is high (like Dutch surface water habitats). 2. Weighted averaging was used to reassign 650 samples to a typology of 40 community types, testing the representativeness of different subsets of data: (i) four different types of data (presence/absence, raw, ²log‐ and ln‐transformed abundance), (ii) three subsets of ‘indicator’ taxa (taxa with indicator weights 4–12, 7–12, and 10–12) and (iii) single taxonomic groups (n = 14) by determining the classification error. 3. ²log‐ and ln‐transformed abundances resulted in the lowest classification error, whilst the use of qualitative data resulted in a reduction of 10% of the samples assigned to their original community type compared to the use of ln‐transformed abundance data. 4. Samples from community types with a high number of unique indicator taxa had the lowest classification error, and classification error increased as similarity among community types increased. Using a subset of indicator taxa resulted in a maximum increase of the classification error of 15% when only taxa with an indicator weight 10–12 were included (error = 49.1%). 5. Use of single taxonomic groups resulted in high classification error, the lowest classification error was found using Trichoptera (68%), and was related to the frequency of the taxonomic group among samples and the indicator weights of the taxa. 6. Our findings that the use of qualitative data, subsets of indicator taxa or single taxonomic groups resulted in high classification error implies low taxonomic redundancy, and supports the use of all taxa in characterising a macroinvertebrate community, in particular in areas where habitat diversity is high.     

Determination of priority areas for amphibian conservation in Guerrero (Mexico), through systematic conservation planning tools

Guerrero is one of the most diverse states of Mexico, containing a large number of endemic and endangered amphibian species. However, it is one of the less protected and studied states of the country. Here, we determined the potential distribution of all amphibian species in a risk category present in Guerrero and defined priority areas for amphibian conservation in the state. We modelled the potential distribution of 32 species using the maximum entropy modelling algorithm. These models were used to define priority areas through systematic conservation planning tools. The most important variables explaining species’ potential distribution were measures of climate variability, particularly temperature seasonality. The priority areas for amphibian conservation identified covered a total area of 12,212.72 km² and contained an important proportion (almost a third) of the cloud mountain forests of the state. The most important planning units for meeting species targets and the most important planning units in terms of biodiversity overlapped in approximately the same planning units, located in the biogeographic regions of the Sierra Madre del Sur and the Pacific Coast. Finally, from the total priority areas identified, only 0.31% (38.17 km²) is currently protected within the existing natural protected areas in Guerrero. Thus, we consider that it is essential to protect additional natural areas in the state. Areas Voluntarily Destined for Conservation (ADVC) may be a good option; however, action must be taken to ensure the legitimacy of the processes by the local people and to avoid privileging only certain members of the community.     

Towards a theoretical basis for ecosystem conservation

Humans have altered the environment so severely that extinction events are now occurring at rates unprecedented in modern history. In order to slow this trend, conservation actions must be taken to protect biodiversity, beyond just saving flagship species. Some governmental and conservation organizations have responded by committing to ecosystem conservation but, as yet, there is no coherent strategy for how this can be carried out. This report introduces many of the theoretical aspects that will need to be considered for the development of a coherent ecosystem conservation policy. The approach includes analyzing a hierarchy of interaction-based local coexistence mechanisms within a regional and historical context. This approach points toward the need for prioritizing sensitive habitats using local interaction models; considering the effects of historical exploitation mechanisms, which are now often missing; and evaluating regional diversity influences further to identify circumstances where system-wide habitat improvements deserve more emphasis.     

Patterns of early succession on bare peat in a Swiss mire after a bog burst

Questions: How does plant diversity (species richness, species abundance and rate of change) evolve in early succession on bare peat? Does succession converge towards one equilibrium stage or end up in several stages? Is there a regular pattern in succession velocity? Location: A mire in the calcareous Jura Mountains of northwest Switzerland. Method: Twenty‐one 1‐m² permanent plots on bare peat were used to monitor temporal stages over a 21‐year period (1988 to 2008) in a Swiss mire where a slide occurred in 1987. Species diversity and life forms were analysed based on Shannon's equitability index and cover. We used classification and metric ordination techniques to investigate patterns of successional rates and trends. The high temporal resolution of the survey allowed the pattern of succession velocity to be analysed. Results: Species richness increased continuously over the 21 years of succession. The highest cover throughout the study period was the life form sedge. Time trajectories of the 21 plots revealed three alternative pathways towards intermediate equilibrium stages in the first years, still not converging in the later stages. Changes in succession velocity reached a first maximum about 6 years after the slide had occurred and a second maximum 12 years later.     

Sustainability indicator systems within urban governance: Usability analysis of sustainability indicator systems as boundary objects

While sustainability indicator systems (SIs) have proven to be valuable rational tools for improving the availability of information related to the relationship of cities and communities to natural limits, the indicators movement has achieved limited instrumental uptake in policy. This paper begins from a recognition that instrumental use of sustainability indicator systems is rare. Greater potential impact exists for SIs designed to be much more attentive to their conceptual and political values within their particular social and political context. In other words, greater attention to what has been called the governance of indicator systems, or the ways in which SIs fit as policy tools within a multilevel and multiactor governance context, is key to increasing their utility. This is particularly true given the need for decisive policy change, or even the introduction of a new development path, which is asserted within the sustainability agenda.Understanding the real and potential utility of indicator systems within multiactor governance processes, in which their roles are primarily rhetorical, conceptual and political, is facilitated by thinking about indicator systems as boundary objects, tools which open up dialogue, information sharing, learning and consensus-building across different policy boundaries: between experts and nonexperts, formal government and different nongovernment actors, higher-order governments and lower-order governments. This paper offers a comparative analysis of three sustainability indicator systems in the North American context – Vancouver's Vital Signs (Vancouver Foundation), Seattle's Happiness Initiative, and LEED-ND (US Green Building Council) – all of which have shown some success in operationalizing a new policy boundary as a means of making conceptual and political contributions to governance practices. The specific boundaries operationalized, the different approach taken by each project, and the usability demonstrated by each project at that boundary in terms of salience, legitimacy and credibility, are assessed comparatively. In general, the trajectory in design and use of ecological and sustainability indicators demonstrates an increase in appetite, aptitude and numbers of channels for use in processes of governance; however, these factors vary with the local social–political opportunity structure. This analysis presents the advances made as well as the tradeoffs evident in these cases across the gamut of different forms of usability of nongovernmental indicator systems designed for use as boundary objects, and suggests a path forward for indicator work which aims to change policy, from a governance perspective.     

Long-term study of litter decomposition on a Pennine peat bog: which regression?

It is estimated that in the northern hemisphere one-third of the world pool of soil carbon is contained in peat resulting from an incomplete decomposition of plant remains. The time course for the decomposition of the predominant plant litters on a Pennine moorland in northern England is reported for a study extending over 23 years. Spatial variation of the weight remaining of decomposing litters increased with time. This experimental study gave an age for the upper layers of the bog and a curve for long-term decay based on direct observation rather than inferred from profile samples or from short-term observations. It showed that short-term observations can give misleading results in the long term, with a variety of litters with differing early decay rates ultimately making a similar contribution to accumulation. Spatial variation of the weight remaining of the decomposing litters increased with time, so that variation within micro-environments, or within apparantly uniform substrates, may contribute significantly to organic matter accumulation. An asymptotic curve best described the long-term course of decomposition leading to the accumulation of peat. The use of the model for the three litter types, Calluna vulgaris, Eriophorum vaginatum and Rubus chamaemorus, is described and the implication of the results for modelling of organic matter accumulation are then discussed. Received: 20 October 1996 / Accepted: 27 July 1997     

A proteomic approach for studying insect phylogeny: CAPA peptides of ancient insect taxa (Dictyoptera, Blattoptera) as a test case

Background  

Neuropeptide ligands have to fit exactly into their respective receptors and thus the evolution of the coding regions of their genes is constrained and may be strongly conserved. As such, they may be suitable for the reconstruction of phylogenetic relationships within higher taxa. CAPA peptides of major lineages of cockroaches (Blaberidae, Blattellidae, Blattidae, Polyphagidae, Cryptocercidae) and of the termite Mastotermes darwiniensis were chosen to test the above hypothesis. The phylogenetic relationships within various groups of the taxon Dictyoptera (praying mantids, termites and cockroaches) are still highly disputed.     

Multiple gradients in mire vegetation: a comparison of a Swedish and an Italian bog

The major environmental gradients underlying plant species distribution were outlined in two climatically and bio-geographically contrasting mires: a Swedish bog in the boreo-nemoral zone, and an Italian bog in the south-eastern Alps. Data on mire morphology, surface hydrology, floristic composition, peat chemistry and pore-water chemistry were collected along transects from the mire margin (i.e., the outer portion of the mire in contact with the surrounding mineral soil) towards the mire expanse (i.e., the inner portion of the mire). The delimitation and the extent of the minerotrophic mire margin were related to the steepness of the lateral mire slope which, in turns, controls the direction of surface water flow. The mineral soil water limit was mirrored in geochemical variables such as pH, alkalinity, Ca²⁺, Mg²⁺, Al³⁺, Mn²⁺, and SiO₂ concentrations in pore-water, as well as Ca, Al, Fe, N and P contents in surface peat. Depending on regional requirements of plant species, different species were useful as fen limit indicators at the two sites. The main environmental factors affecting distribution of habitat types and plant species in the two mires were the acidity-alkalinity gradient, and the gradient in depth to the water table. The mire margin – mire expanse gradient corresponds to a complex gradient mainly reflected in a differentiation of vegetation structure in relation to the aeration of the peat substrate.