The Importance of Regional, System-Wide and Local Spatial Scales in Structuring Temperate Estuarine Fish Communities

An extensive literature base worldwide demonstrates how spatial differences in estuarine fish assemblages are related to those in the environment at (bio)regional, estuary-wide or local (within-estuary) scales. Few studies, however, have examined all three scales, and those including more than one have often focused at the level of individual environmental variables rather than scales as a whole. This study has identified those spatial scales of environmental differences, across regional, estuary-wide and local levels, that are most important in structuring ichthyofaunal composition throughout south-western Australian estuaries. It is the first to adopt this approach for temperate microtidal waters. To achieve this, we have employed a novel approach to the BIOENV routine in PRIMER v6 and a modified global BEST test in an alpha version of PRIMER v7. A combination of all three scales best matched the pattern of ichthyofaunal differences across the study area (rho = 0.59; P = 0.001), with estuary-wide and regional scales accounting for about twice the variability of local scales. A shade plot analysis showed these broader-scale ichthyofaunal differences were driven by a greater diversity of marine and estuarine species in the permanently-open west coast estuaries and higher numbers of several small estuarine species in the periodically-open south coast estuaries. When interaction effects were explored, strong but contrasting influences of local environmental scales were revealed within each region and estuary type. A quantitative decision tree for predicting the fish fauna at any nearshore estuarine site in south-western Australia has also been produced. The estuarine management implications of the above findings are highlighted.

A triage approach to improve the relevance of marine ecosystem services assessments

Ecosystem services assessments are increasingly being used to inform marine policy and planning. These assessments involve significant time, effort, and expertise. It is important at the outset to determine which of many ecosystem services should be quantified and which measures of ecological output, economic impact, or value should be assessed. Furthermore, the literature shows that in practice such assessments are unevenly applied and rarely used effectively in decision-making processes. We develop a structured decision-making approach, called a triage, to assess what types of ecosystem services should be assessed to improve the uptake and usefulness of such information in marine planning. Two case studies, in France and the United Kingdom, provide examples of the application of the triage approach.

Can diagnostic triage by general practitioners or rheumatology nurses improve the positive predictive value of referrals to early arthritis clinics?

Objectives: To determine whether diagnostic triage by general practitioners (GPs) or rheumatology nurses (RNs) can improve the positive predictive value of referrals to early arthritis clinics (EACs).

Methods: Four GPs and two RNs were trained in the assessment of early in?ammatory arthritis (IA) by four visits to an EAC supervised by hospital rheumatologists. Patients referred to one of three EACs were recruited for study and assessed independently by a GP, an RN and one of six rheumatologists. Each assessor was asked to record their clinical ?ndings and whether they considered the patient to have IA. Each was then asked to judge the appropriateness of the referral according to predetermined guidelines. The rheumatologists had been shown previously to have a satisfactory level of agreement in the assessment of IA.

Results: Ninety-six patients were approached and all consented to take part in the study. In 49 cases (51%), the rheumatologist judged that the patient had IA and that the referral was appropriate. The assessments of GPs and RNs were compared with those of the rheumatologists. Levels of agreement were measured using the kappa value, where 1.0 represents total unanimity. The kappa value was
0.77 for the GPs when compared with the rheumatologists and 0.79 for the RNs. Signi?cant stiffness in the morning or after rest and objective joint swelling were the most important clinical features enabling the GPs and RNs to discriminate between IA and non-IA conditions.

Conclusion: Diagnostic triage by GPs or RNs improved the positive predictive value of referrals to an EAC with a degree of accuracy approaching that of a group of experienced rheumatologists.

Organisational controls, typologies and time scales of paraglacial gravel-dominated coastal systems

The fundamental controls on the initiation and development of gravel-dominated deposits (beaches and barriers) on paraglacial coasts are particle size and shape, sediment supply, storm wave activity (primarily runup), relative sea-level (RSL) change, and terrestrial basement structure (primarily as it affects accommodation space). This paper examines the stochastic basis for barrier organisation as shown by variation in gravel barrier architecture. We recognise punctuated self-organisation of barrier development that is disrupted by short phases of barrier instability. The latter results from positive feedback causing barrier breakdown when sediment supply is exhausted. We examine published typologies for gravel barriers and advocate a consolidated perspective using rate of RSL change and sediment supply. We also consider the temporal variation in controls on barrier development. These are examined in terms of a simple behavioural model (BARCH) for prograding gravel barrier architecture and its sensitivity to such controls. The nature of macroscale (102–103 years) gravel barrier development, including inherited characteristics that influence barrier genesis, as well as forcing from changing RSL, sediment supply, headland control and barrier inertia, is examined in the context of long-surviving barriers along the southern England coastline.