Coastal defence and the Habitats Directive: predictions of habitat change in England and Wales

Future coastal defence policies and 'natural' processes will have an impact on habitats within Special Areas of Conservation (SAC), Special Protection Areas (SPA) and Ramsar sites. An overview of the potential nature and extent of these changes (losses or gains over the next 50 years) around the coast of England and Wales was carried out to inform policy decisions on the legal and funding aspects of coastal defence options and possible habitat replacement. It is predicted that there could be a net loss of freshwater and brackish habitat of around 4000 hectares, together with a net gain of intertidal (saltmarsh and mudflat/sandflat) habitats of around 770 hectares, with the gains associated with managed retreat ( c .12 500 ha) balancing the expected losses due to coastal squeeze and erosion on the unprotected coast. The likely costs of freshwater and brackish habitat replacement, on a hectare-for-hectare basis, is estimated to be in the order of £50–60 million, including site purchase, set-up and on-going management costs.     

Integrating RapidEye and ancillary data to map alpine habitats in South Tyrol,Italy

In this paper, we present a two-stage method for mapping habitats using Earth observation (EO) data in three Alpine sites in South Tyrol, Italy. The first stage of the method was the classification of land cover types using multi-temporal RapidEye images and support vector machines (SVMs). The second stage involved reclassification of the land cover types to habitat types following a rule-based spatial kernel. The highest accuracies in land cover classification were 95.1% overall accuracy, 0.94 kappa coefficient and 4.9% overall disagreement. These accuracies were obtained when the combination of images with topographic parameters and homogeneity texture was used. The habitat classification accuracies were rather moderate due to the broadly defined rules and possible inaccuracies in the reference map. Overall, our proposed methodology could be implemented to map cost-effectively alpine habitats over large areas and could be easily adapted to map other types of habitats.     

The role of local taboos in the management of marine fisheries resources in Tanzania

Contemporary government rules for fisheries resources management in developing countries have been challenged for their inadequacy. The search for modern management models for coastal and marine resources could be usefully informed by wealth of traditional knowledge that enabled communities to sustainably live with their environment for centuries or millennia. Local taboos, defined as implicit or explicit social rules prohibiting certain actions, have played an important part in many traditional approaches to resource use. A mixed methods approach was used to investigate how local taboos play a role in the management of fisheries resources in some rural and urban coastal communities of Tanzania. Focus group discussions, key informant interviews, participant observations and questionnaire surveys were used to gather primary data. Data were analyzed both qualitatively and quantitatively. The study identified a number of potential local taboos in the management of fisheries resources and their habitats in coastal Tanzania. While these taboos showed some potential for applications in modern management approaches, a majority of fishers indicated non-compliance to most of them, especially in urban areas. A number of reasons are revealed to have attributed to the non-compliance of these taboos. These findings suggest the prospect for judicious integration of traditional practices with modern strategies, to enhance compliance. More studies on traditional knowledge that has a role in fisheries resources management are recommended, as are biophysical assessments in conjunction with traditional practices to reveal their scientific benefits. Successful community-based fisheries resources management in Tanzania will draw on modern and traditional perspectives.     

Mapping the functional dimension of vegetation series in the Mediterranean region using multitemporal MODIS data

ABSTRACT

Monitoring the structural and functional dimensions of natural vegetation is a critical issue to ensure effective management of biodiversity. While coarse-resolution satellite image time-series have been used extensively to monitor vegetation physiognomies, their potential to describe plant species composition remains understudied. The objective of this study is to assess the potential of annual time-series of MODIS images to discriminate combinations of plant communities, called “vegetation series,” and characterize their structural and functional dimensions at the landscape scale. Twelve vegetation series were mapped in a 16 574 ha study area in a Mediterranean context located in Corsica (France). First, the structural dimension of vegetation series was examined using a random forest (RF) model calibrated with a reference field map to (i) measure the importance of each MODIS image in discriminating vegetation series; (ii) quantify the influence of the number of dates on model accuracy; and (iii) map the vegetation series with the optimal subset of MODIS images. Second, the functional dimension of vegetation series was analyzed by ordinating three functional indices through principal component analysis. These indices were the annual sum of normalized difference vegetation index (NDVI), the annual amplitude of NDVI, and the date of maximum NDVI, considered as a proxy for annual primary production, seasonality of carbon fluxes, and vegetation phenology, respectively. Results showed that (i) vegetation series were mapped accurately (median Kappa index 0.70, median overall accuracy 0.76), preferably using images acquired from February to August; (ii) at least 10 MODIS images were required to achieve sufficient accuracy; and (iii) a functional gradient was detected, ranging from high annual net primary production with low seasonality of carbon fluxes and early phenology in Mediterranean vegetation series to low annual net primary production with high seasonality of carbon fluxes and late phenology in alpine vegetation series.     

贵州喀斯特洞穴动物多样性及其生境研究——以黔西县红林地区为例

通过四次对青冈林洞、洗线洞和水响洞的调查,共获37种动物。各种类数量优势分别为有光带的蚁蛉幼虫、蕈蚊,弱光带和黑暗带水域的红点髭蟾蝌蚪以及洞壁的斑灶马。2001年10月和2003年3月,青冈林洞、洗线洞和水响洞分别有动物群落15、13和10种类型,优势群落为斑灶马、红点髭蟾蝌蚪和蚁蛉幼虫。动物的取食、隐蔽、繁殖、栖息等环境在不同时期的变换引起这一区域洞穴动物在种类、数量和空间分布等的变化,人类活动则加大了生境的差异。食物-陷阱法可用于部分动物的相对数量的调查。      

Developing water quality standards for coastal dolphins

The EU Habitats Directive requires Member States to consider the potential impact of sewage discharges on protected wildlife populations, but efforts to reduce these threats are constrained by the lack of appropriate water quality guidelines for wildlife. In Scotland, recommendations for higher discharge standards in areas frequented by bottlenose dolphins have been criticised on the basis of scientific uncertainty. This Viewpoint article outlines the background to this issue, and discusses whether the scientific frameworks used for assessing water quality standards for human bathers can realistically be used to develop water quality standards for coastal dolphins. Importantly, it highlights that widely accepted EU standards for human bathers are based on extremely limited scientific data, and argues that unrealistic demands for empirical data from wildlife populations should not prevent more precautionary measures being introduced to reduce disease risks to these species.