A review of landscape ecology tools to assess habitat loss and ecological connectivity in Luxembourg

Oral Presentation Abstract: The Luxembourgish population is anticipated to reach one million people in the next fifty years. The future territorial strategy of Luxembourg is wanting to consider the potential impacts that new infrastructure and urban development can have on the loss of habitats and ecological connectivity. To evaluate the consequences of land use changes, priority interventions to avoid or mitigate impacts specific to habitat fragmentation due to new developments must be identified. In this sense, a better understanding of potential habitat loss and landscape fragmentation requires a specific assessment that measures land cover changes and their consequences on ecological connectivity. This understanding can also add another dimension to integrated sustainability assessments. This paper reviews and selects state-of-the-art practices and current tools to measure habitat loss, landscape fragmentation, and changes in ecological connectivity that could guide spatial planners and decision makers in Luxembourg to evaluate the spatial impact of demographic growth. A literature review permitted the identification and selection of existing landscape and connectivity metrics to assess habitat loss and fragmentation as well as structural ecological connectivity, which could be calculated using spreadsheet tables or freely available software such as Fragstats and Conefor. Tools and software to measure ecological connectivity in a spatially explicit manner were also identified and selected. For landscape metrics, the final selection was based on two criteria: simplicity, and history of previous applications. For the selection of tools, accessibility was added to the previous criteria. Finally, the selected landscape metrics and one connectivity tool were applied at the country-scale to assess their adequacy within the Luxembourgish context and compare their performance. Several class and landscape level metrics based on distance and graph-theory are identified out of the literature review. From those, percent of land cover (PLC), patch density (PD), average weighted mean patch size (AWMPS), contagion (CON), effective mesh size (EMS), integral index of connectivity (IIC), and probability of connectivity (PC) are among the most simple and effective to understand specific habitat loss and landscape fragmentation. Graph-based (e.g. Condatis, LandScape Corridors) and stochasticity movement modelling tools (e.g. Rangeshifter) are also identified, from which LandScape Corridors was tested. The application to Luxembourg shows the value of EMS, IIC, and PC as stand-alone metrics for assessing fragmentation and connectivity, meanwhile PLC, PD, and AWMPS together could be useful to inform habitat loss and fragmentation processes. LandScape Corridors was tested due to their easiness to use and its visual outputs are considered adequate to inform planning strategies. The selected metrics and tools can inform spatial planners and experts in Luxembourg on habitat loss and fragmentation as well as ecological connectivity. These can facilitate the consideration of impacts related to habitat loss and fragmentation in integrated sustainability studies.