► The Agri-Environmental Footprint Index can evaluate environmental effects of AES. ► Most case studies showed better environmental performance from scheme farms. ► A participatory approach can ...provide local customisation of the evaluation. ► Consultation provides understanding of the relative importance of scheme objectives.
The Agri-Environment Footprint Index (AFI) has been developed as a generic methodology to assess changes in the overall environmental impacts from agriculture at the farm level and to assist in the evaluation of European agri-environmental schemes (AES). The methodology is based on multi-criteria analysis (MCA) and involves stakeholder participation to provide a locally customised evaluation based on weighted environmental indicators. The methodology was subjected to a feasibility assessment in a series of case studies across the EU. The AFI approach was able to measure significant differences in environmental status between farms that participated in an AES and non-participants. Wider environmental concerns, beyond the scheme objectives, were also considered in some case studies and the benefits for identification of unintentional (and often beneficial) impacts of AESs are presented. The participatory approach to AES evaluation proved efficient in different environments and administrative contexts. The approach proved to be appropriate for environmental evaluation of complex agri-environment systems and can complement any evaluation conducted under the Common Monitoring and Evaluation Framework. The applicability of the AFI in routine monitoring of AES impacts and in providing feedback to improve policy design is discussed.
Aspects of the ecology of the Lepidoptera associated with Calluna vulgaris on managed northern heaths were studied between 1991-1993 at five study areas in Durham, Northumberland and southern ...Scotland. The study areas were northern heaths that were managed by rotational burning and each comprised a mosaic of even-aged Calluna stands. Lepidoptera were studied in the larval stage of development. A range of even-aged Calluna stands, with different ages and vegetation structures were selected as sample sites and the larval assemblages in the different stands were monitored by sweepnet sampling. A total of 29 species of macrolepidoptera and 3 species of microlepidoptera larvae were recorded. Species lists were similar at the five study areas, but the relative abundance of individual species varied between sites. The degree of similarity between communities was not related to the distance between study areas. The densities of many macrolepidoptera species were closely correlated with Calluna height. Intercorrelation between vegetation architecture variables meant that other factors e.g. green shoot density or flower density could also have been responsible. Lepidoptera diversity varied with Calluna height, due to changes in the dominance of common species and the presence of additional rare species at certain heights. However patterns in diversity were not consistent between study areas. The concentrations of total leaf nitrogen, total phenolics and water were significantly higher in current year's Calluna leaves than in the shoots formed in previous years. In same-aged leaves, there was no relationship between plant age and the concentrations of leaf nitrogen or phenolics. The water content of same-aged leaves was negatively correlated with stand age at some sites and at certain sampling times. Larvae offered different choices of ericaceous plants exhibited significant preferences for different plant species and also for the current year's Calluna leaves rather than previous years' growth. Mechanisms that could be responsible for the observed distribution patterns of larvae in different heights of Calluna are discussed. The maintenance of a mosaic of different-aged Calluna stands on northern heath represents the best conservation strategy for Lepidoptera by maintaining species diversity at a site.
This paper explores the potential of rule-based habitat models to predict the occurrence of some common species in arable conditions. Models were developed for 10 arable plant species, 7 Hemiptera ...species, 8 carabid species and for 5 bird species whose ecology was sufficiently known. Rule sets linking species occurrence to environmental variables were produced using available literature and expert knowledge about ecological requirements of the selected species. Environmental variables described the nature and condition of habitats at various scales, ranging from vegetation quadrat to the landscape in a 1 km radius of species sampling sites. The performance of the 34 models developed was assessed in two areas of England. Results show the rule-based habitat models developed for arable plants and birds were not very successful with Cohen's k values often < 0.4 for plants and very close to 0 for all bird species. Conversely, rule-based models performed surprisingly well for carabids and Hemiptera with k values on average > 0.4. This suggests that ecological knowledge on these invertebrate species is more complete than we expected. The effect of species prevalence on model performance and the potential application of knowledge-based habitat models in the context of biodiversity assessment are discussed.
The potential of habitat-based models was explored to predict the occurrence of carabid beetles in arable conditions. It was hypothesised that: (i) the habitats surrounding a location were good ...predictors of the occurrence of the most common carabid species; (ii) the current knowledge on habitat associations for some individual species was sufficient to develop accurate predictive models. The performance of knowledge-based models was assessed for eight well-studied carabid species. Rule sets were produced using an extensive database describing the nature and condition of the habitats recorded within a 50
m radius of the sampling sites. The performance was compared to a more classical approach based on logistic regression (LR) models, using the same original information summarised into 19 variables by correspondence analysis (CA). The performance of the rule-based (RB) models was higher than expected by chance for species occurring in less than 70% of the sites (
k>0.4) and was relatively consistent across the three areas of England where they were tested. Models developed for widespread species had a high prediction success (PS) but no discriminatory ability (low
k value). LR and RB approaches gave comparable results for species of average prevalence (30–70%) while for species occurring in less than 30% of the sampled sites, the RB approach performed significantly better than the LR one. It is suggested that knowledge-based approaches could be used more widely to predict the distribution of invertebrate species. The effect of species prevalence and the potential application of knowledge-based habitat-models in the context of biodiversity assessment are discussed.
In recent years, a spate of dangerous invasive alien species (IAS) have become established in the Caribbean, and many others threaten the region. Some established species continue to spread, causing ...economic and environmental damage. This paper reviews the status and significance of IAS in the Caribbean. Factors contributing to the upsurge of new problems and pathways are discussed from a perspective of prevention. Steps recently taken to prevent or mitigate the impact of these species are also discussed. On the basis of these experiences, suggestions are made for the future direction of efforts to prevent or manage such invasive species within the Caribbean context.
