Fragmented landscapes : Assessment and communication of landscape connectivity in human-dominated landscapes

• This licentiate thesis summarizes the first half of my PhD on the theme of management of fragmented landscapes. The thesis applies – and reflects on the use of – network analysis of connectivity in relation to landscape planning. Relevant theory on knowledge management and spatial ecology is summarized and discussed in connection with two papers.Paper I centers on municipal ecologists and environmental planners in the Stockholm region. They state that connectivity is rarely considered enough in planning and that assessment tools are lacking. Paper I studies the benefits and difficulties of using network analysis to manage connectivity in land-use planning. Among the main difficulties was the choice of model species and access to input data. The main strengths were the graphical and quantitative results, the potential for social learning, identification of critical sites and to relate local planning and ecology to the regional landscape.Paper II applies network methodology to quantify habitat availability of fragmented lichen-type forests in protected areas in northern Sweden. It studies a dynamic landscape that is continuously rearranged by forestry, with consequences that depend on species’ abilities to compete for resources in protected habitats, and to disperse through unprotected mature forest stands. We discuss the results with reference to the planning of forestry and protected areas, and to the resilience of species to patchy disturbance regimes.To end I propose a continuation of research, including a methodological development of network analysis; a sociological study of the acceptance of ecological advice in urban planning; and an integration of social and ecological network analysis to compare patterns of cross-municipal collaboration with landscape connectivity.

• This paper studies the current use and the potential benefits and difficulties of using network analysis to manage landscape connectivity in land-use planning and environmental assessments. The results are based on interviews with 13 municipal ecologists and environmental planners in Stockholm, Sweden, who had previously been involved in a joint project between practitioners and researchers to develop a GIS-tool for network-based connectivity analysis. According to the respondents, connectivity is rarely considered enough in municipal planning and none of the practitioners used systematic methods to assess landscape connectivity. In the few reported cases of connectivity consideration, focus was on citizens' recreational appreciation of contiguous vegetation. The practitioners anticipate that overall and patch-level connectivity will help them communicate the meaning and implications of connectivity to other actors, and better assess the importance of certain habitats affected by development plans. The main difficulties of implementing network-based connectivity analyses reported by the respondents related to the choice of model species and lack of model input in terms of landscape data, habitat requirements and dispersal distances. The main strengths were graphical, quantitative and credible results, the ability to compare planning alternatives and to find critical sites in a more objective manner, and to relate the local planning and ecology to the regional landscape. Many respondents stressed the role of connectivity assessments in the endeavor to overcome current mismatches of ecological and administrative scales.

• This article presents a connectivity analysis of boreal lichen forests in northern Sweden, which is a habitat type that hosts many red listed species. We evaluate connectivity of habitat in nature reserves using a network approach, and examine how areas subject to less strict or informal protection schemes supplement the reserve network. Our results show that the current spatial arrangement of protected areas favors certain species, determined by their specific habitat specialization and dispersal capacity. We then quantify the significance of mature forests in the surrounding unprotected landscape. Results show that unprotected mature forests provide large amounts of temporary habitat for species that can colonize and disperse further before logging occurs. Our analysis also indicates that unprotected areas increase the spatial resilience of sensitive species that mostly occur in protected natural forests, by providing connectivity to other protected areas in the event of disturbance in a reserve. The results are discussed with reference to the spatial planning of harvest and strategies of area protection.

Ämnesord

SAMHÄLLSVETENSKAP  -- Annan samhällsvetenskap -- Tvärvetenskapliga studier inom samhällsvetenskap (hsv//swe)

SOCIAL SCIENCES  -- Other Social Sciences -- Social Sciences Interdisciplinary (hsv//eng)

NATURVETENSKAP  -- Biologi -- Ekologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Ecology (hsv//eng)

Nyckelord

Fragmentation

Connectivity

Network

Spatial

Landscape

Dispersal

Planning

Social-Ecological

Scale

IIC

STS

naturresurshushållning

Natural Resources Management

Publikations- och innehållstyp

vet (ämneskategori)

lic (ämneskategori)