The increasing relevance and importance of the subject of landscape ecology to bio geography are introduced. Research into landscape and plant community boundaries, never theless, remains comparatively neglected. In particular, the nature of those boundaries in terms of the patterns of floristic change and related ecosystem properties constitutes a potentially signifi cant new area of research for biogeographers. The term 'ecotone' has traditionally been used to describe boundaries between plant communities and ecosystems at a range of scales. Various definitions are presented and the often confusing terminology surrounding the word 'ecotone' is reviewed. Boundary types range from sharp, clearly defined boundaries (ecotones) between more highly modified plant communities and anthropogenically created land-use types at one extreme, to more gradual and diffuse boundaries (ecoclines) between natural and semi-natural plant communities at the other. It is proposed that the term 'transitional area' is used to describe all types of vegetation boundary when working at the local/community scale. There is little literature of direct significance to the subject of transitional areas. The concept can only be meaningfully discussed in the context of recent developments in the conceptualization of the plant community and these are summarized. The importance of mosaics within plant communities is described and the need to understand and recognize mosaics when studying transitional areas between plant communities is emphasized. The range of research methods available to describe and analyse variations in patterns of floristics and associated environmental variables across transitional areas is then critically reviewed. The potential relevance of remote sensing and geographical information systems, net work analysis and fractals is demonstrated. Ideas on possible adaptations of sampling strategies for the description of floristics and environmental/biotic factors to cater for boundary/transitional area situations are presented and the concept of a rectangular sampling area as an alternative to the more normal linear transect is introduced. The traditional approach to the description of vegetation change across boundaries using transects and similarity coefficients has now been superseded by new developments, notably moving-window analysis, the Mantel test, pattern analysis, semi-variograms, spectral analysis and analysis for spatial autocorrelation, and the scope of these methods is summarized. Finally, the dynamics of plant communities and their boundaries are considered and the implications of research into transitional areas for vegetation management and biological conserv ation are assessed. The importance of this whole subject as a possible new focus for biogeography and spatial ecology is then reiterated.

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Surface sample pollen assemblages and vegetation data collected from two East Anglian fen carr sites with adjacent dry woodland belts are analysed to estimate the relevant source area of pollen (RSAP) and the relative pollen productivity (RPP) values for the major canopy trees. The 'relevant source area of pollen' is found to be on the order of 50-150 m, comparable with but slightly greater than estimates for forest hollow contexts in dry woodlands. Estimates of pollen productivity relative to Quercus are then compared with published values from south Sweden. Betula and Corylus values are similar, but some values estimated for taxa characteristic of wetter habitats, and therefore competitively advantaged in the fen carr A system (Alnus, Salix and Fraxinus), are substantially higher at one or both sites. The results suggest that HOLOCENE palaeoecological records from fen carr systems should be interpreted as reflecting predominantly local RESEARCH vegetation signals once the tree canopy is established.

The effects of streets on biodiversity is an important aspect of urban ecology, but it has been neglected worldwide. Several vegetation attributes (e.g. street tree density and diversity) have important effects on biodiversity and ecological processes. In this study, we evaluated the influences of urban vegetation—represented by characteristics of street trees (canopy size, proportion of native tree species and tree species richness)—and characteristics of the landscape (distance to parks and vegetation quantity), and human impacts (human population size and exposure to noise) on taxonomic data and functional diversity indices of the bird community inhabiting streets. The study area was the southern region of Belo Horizonte (Minas Gerais, Brazil), a largely urbanized city in the understudied Neotropical region. Bird data were collected on 60 point count locations distributed across the streets of the landscape. We used a series of competing GLM models (using Akaike's information criterion for small sample sizes) to assess the relative contribution of the different sets of variables to explain the observed patterns. Seventy-three bird species were observed exploiting the streets: native species were the most abundant and frequent throughout this landscape. The bird community's functional richness and Rao's Quadratic Entropy presented values lower than 0.5. Therefore, this landscape was favoring few functional traits. Exposure to noise was the most limiting factor for this bird community. However, the average size of arboreal patches and, especially the characteristics of street trees, were able to reduce the negative effects of noise on the bird community. These results show the importance of adequately planning the urban afforestation process: increasing tree species richness, preserving large trees and planting more native trees species in the streets are management practices that will increase bird species richness, abundance and community functional aspects and consequently improve human wellbeing and quality of life.

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Green activism and guerrilla gardening lie at the more informal end of the urban food growing movement, but little is known about the extent of this practice or the future of such unplanned activities. Accordingly, this paper firstly explores a range of informal Urban Agriculture practices, illuminating the practice within Europe, North America, Africa and other continents. The paper then proceeds to focus explicitly on Salford, UK, where guerrilla gardening is being encouraged by the local authority. Using ethnographic and interview data, we focus on the actors involved, their relationship with authority and the wider impact of their activities; exploring their motives, aspirations, values and beliefs. The results reveal the ability of the informal movement to regenerate 'forgotten' space and bring communities together, and the 'darker' side of the activity, with actors sometimes restricting access to colonised land. Ultimately, the paper reveals how this movement is expanding and that more research is required to better understand the actions of those who pursue a more informal approach to urban gardening and those who seek to regulate land use activity.

The rise of Urban Agriculture projects across the UK has led to a surge of interest in their efficacy and resulting social impacts. Real Food Wythenshawe is a Lottery-funded urban food project in the UK that aims to teach the population of Wythenshawe to grow their own food and to cook from scratch. The area, popularly referred to as 'Europe's largest council estate', suffers from high levels of deprivation and has been described as a 'food desert' due to a perceived lack of access to fresh fruit and vegetables (Small World Consulting, 2013). In order to encourage Wythenshawe residents to grow their own food and to increase access to fresh fruit and vegetables, Real Food Wythenshawe aims to transform unused areas of land into growing spaces, such as allotments and community gardens. This paper focuses on research conducted at a community garden in Wythenshawe, established by Real Food Wythenshawe as an example of a 'meanwhile' or temporary growing site for people affected by cancer. The research investigated the impact of the growing activities on community garden participants through a series of observations and interviews. The findings suggest that the benefits of the space were multiple and diverse, ranging from increased growing knowledge to therapeutic effects, while there has been minimal effect on participants' dietary behavior. The organization of the community garden also raises questions over some of the practicalities of temporary urban growing sites and highlights the tensions that can arise between small community growing groups and larger institutions with control over land use. These findings add to a growing body of research that considers the value of growing in the city and reflects on the role of community gardening in deprived urban areas of the UK.

Terrestrial laser scanners (TLS) have the potential to revolutionise measurement of the three-dimensional structure of vegetation canopies for applications in ecology, hydrology and climate change. This potential has been the subject of recent research that has attempted to measure forest biophysical variables from TLS data, and make comparisons with two-dimensional data from hemispherical photography. This research presents a systematic comparison between forest canopy gap fraction estimates derived from TLS measurements and hemispherical photography. The TLS datasets used in the research were obtained between April 2008 and March 2009 at Delamere Forest, Cheshire, UK. The analysis of canopy gap fraction estimates derived from TLS data highlighted the repeatability and consistency of the measurements in comparison with those from coincident hemispherical photographs. The comparison also showed that estimates computed considering only the number of hits and misses registered in the TLS datasets were consistently lower than those estimated from hemispherical photographs. To examine this difference, the potential information available in the intensity values recorded by TLS was investigated and a new method developed to estimate canopy gap fraction proposed. The new approach produced gap fractions closer to those estimated from hemispherical photography, but the research also highlighted the limitations of single return TLS data for this application.