Activating landscape ecology: a governance framework for design-in-science

Context

In response to predominantly local and private approaches to landscape change, landscape ecologists should critically assess the multiscalar influences on landscape design.

Objectives

This study develops a governance framework for Nassauer and Opdam’s “Design-in-Science” model. Its objective is to create an approach for examining hierarchical constraints on landscape design in order to investigate linkages among urban greening initiatives, patterns of landscape change, and the broader societal values driving those changes. It aims to provide an integrative and actionable approach for landscape sustainability science.

Methods

This framework is examined through an ethnographic study of public policy processes surrounding the urban tree initiatives in Boston, MA; Philadelphia, PA; and Baltimore, MD.

Results

These initiatives demonstrate the impact of political and economic decentralization on urban landscape patterns. Their collaborative governance approach incorporates diverse resources to implement programming at a fine-scale. The predominant tree giveaway program fragments the urban and regional forest.

Conclusion

Spatial and temporal fragmentation undermines the long-term security of urban greening programs, and it suggests reconsideration of the role of state regimes in driving broad scale spatial planning.

     

Developing a complementary framework for urban ecology

Cities are characterized by dynamic interactions between socio-economic and biophysical forces. Currently more than half of the global population reside in cities which influence the global biogeochemical cycles and climate change, substantially exacerbating pressures on urban pollution, water quality and food security, as well as operating costs for infrastructure development. Goods and services such as aesthetic values, water purification, nutrient recycling, and biological diversity, that urban ecosystems generate for the society, are critical to sustain. Urban planners are increasingly facing the considerable challenges of management issues for urban ecosystems. Poor understanding of the complementary roles of urban ecology in urban infrastructure, and the functioning of ecosystems and ecological resilience of a complex human-dominated landscape has impeded effective urban planning over time, resulting in social disharmony. Here a complementary framework for urban ecology is proposed, in which ecosystems interact with land use, architecture and urban design – “E-LAUD” – affecting ecosystem and human health, and building on the concept that land uses in urban green areas, road-strips, wetlands, ‘habitat islands’ and urban architecture could synergistically benefit when clustered together in different combinations of urban landscapes. It is proposed that incorporation of the E-LAUD framework in urban planning forms the context of a new interdisciplinary research programme on ecological resilience for urban ecosystems and helps promote ecosystem services.     

Landscape ecology as a foundation for sustainable conservation

Landscape ecology and conservation share a common focus on places, but they differ in their perspectives about what is important about those places, and the integration of landscape ecology into conservation is far from complete. I consider four ways in which landscape ecology can contribute to conservation. First, protected areas that are established for conservation are not stand-alone isolates. They exist in the context of broader landscape mosaics, which may encourage or discourage movements of individuals into and out of an area. Second, the landscape surroundings of a preserve may contain threats to the biodiversity within the preserve, many of them consequences of human activities. In combination, these relationships with the surroundings may make the “effective area” of a preserve different from that shown on a map. Third, the scale of an administrative area or of management action may not coincide with the scales of populations, disturbances, or ecological processes, creating challenges to both landscape ecology and conservation. Finally, landscapes encompass people and their activities; sustainability of conservation requires consideration of the tradeoffs between human uses and the biodiversity values of a landscape. I illustrate these four themes with a case study of the management of prairie dogs (Cynomys ludovicianus) in the Great Plains of North America, where the tensions between conservation and human land uses are particularly high. Ecologists and conservationists consider prairie dogs as keystone species in these grassland ecosystems and primary targets for conservation, but many private landowners regard them as varmints that consume valuable livestock forage and degrade rangeland condition. Effective conservation of functioning grasslands must include prairie dogs, and this in turn requires that the issues be addressed in terms of the biological, social, and cultural features of entire landscapes. Important as they are, areas protected for conservation cannot by themselves stem the tide of global biodiversity loss. The perspective must be broadened to include the landscapes where people live and work, recognizing the dynamic nature of landscapes and the factors driving land-use change. Landscape ecologists must work together to overcome the cultural differences between their disciplines, and between academic science and conservation practice and management. It can, and must, be done.     

Landscape ecology as a theoretical basis for nature conservation

Conservation of representative biotopes, single species populations or biodiversity usually embraces two or more biotopes, and is often affected by surrounding croplands. The conclusions from landscape ecological studies can, therefore, offer important contributions to conservation, especially at early levels of landscape change or habitat fragmentation. Indicator and keystone species are useful for monitoring and managing fragmented biotopes, respectively. Communities as well as single species are affected by the juxtaposition of successional and climax biotopes, which influence climatic equability, seasonality, productivity and dispersal. Low levels of fragmentation may result in ill-functioning communities, and greater fragmentation may result in species losses and ultimately in the loss of whole communities. Fragmented habitats retain species with high reproductive and dispersal rates and generalized habitat selection. New combinations of interacting species will lead to trivialization of earlier habitat-specific interactions. Validation of these concepts was made with data from a Swedish research program on fragmented biotopes in production landscapes. General reserve selection and methods of management for preserving climax communities, single specialized species and high biodiversity are suggested.     

Spatial resilience: integrating landscape ecology,resilience, and sustainability

Landscape ecology has a high potential to contribute to sustainability in the interactions of people and nature. Landscape ecologists have already made considerable progress towards a more general understanding of the relevance of spatial variation for ecosystems. Incorporating the complexities of societies and economies into landscape ecology analyses will, however, require a broader framework for thinking about spatial elements of complexity. An exciting recent development is to explicitly try to integrate landscape ecology and ideas about resilience in social–ecological systems through the concept of spatial resilience. Spatial resilience focuses on the importance of location, connectivity, and context for resilience, based on the idea that spatial variation in patterns and processes at different scales both impacts and is impacted by local system resilience. I first introduce and define the concepts of resilience and spatial resilience and then discuss some of their potential contributions to the further interdisciplinary integration of landscape ecology, complexity theory, and sustainability science. Complexity theorists have argued that many complex phenomena, such as symmetry-breaking and selection, share common underlying mechanisms regardless of system type (physical, social, ecological, or economic). Similarities in the consequences of social exclusion and habitat fragmentation provide an informative example. There are many strong parallels between pattern–process interactions in social and ecological systems, respectively, and a number of general spatial principles and mechanisms are emerging that have relevance across many different kinds of system. Landscape ecologists, with their background in spatially explicit pattern–process analysis, are well placed to contribute to this emerging research agenda.     

Landscape pattern in topographically complex landscapes: issues and techniques for analysis

Ecological research provides ample evidence that topography can exert a significant influence on the processes shaping broad-scale landscape vegetation patterns. Studies that ignore this influence run the risk of misinterpreting observations and making inappropriate recommendations to the management community. Unfortunately, the standard methods for landscape pattern analysis are not designed to include topography as a pattern-shaping factor. In this paper, we present a set of techniques designed to incorporate the topographic mosaic into analyses of landscape pattern and dynamics. This toolbox includes adjustments to classic landscape indices that account for non-uniform landscape topography, indices that capture associations and directionality in vegetation pattern due to topographic structure, and the application of statistical models to describe relationships between topographic characteristics and vegetation pattern. To illustrate these methods, we draw on examples from our own analysis of landscape pattern dynamics in logged and unlogged forest landscapes in southwestern British Columbia. These examples also serve to illustrate the importance of considering topography in both research and management applications.This revised version was published online in May 2005 with corrections to the Cover Date.     

Emerging trajectories for spatial pattern analysis in landscape ecology

Landscape Ecology - Landscape ecology is an interdisciplinary field, drawing on theories and methods from across the physical, natural, and social sciences. Spatial pattern analysis was built on...     

Landscape services as a bridge between landscape ecology and sustainable development

Landscape ecology is in a position to become the scientific basis for sustainable landscape development. When spatial planning policy is decentralised, local actors need to collaborate to decide on the changes that have to be made in the landscape to better accommodate their perceptions of value. This paper addresses two prerequisites that landscape ecological science has to meet for it to be effective in producing appropriate knowledge for such bottom-up landscape-development processes—it must include a valuation component, and it must be suitable for use in collaborative decision-making on a local scale. We argue that landscape ecological research needs to focus more on these issues and propose the concept of landscape services as a unifying common ground where scientists from various disciplines are encouraged to cooperate in producing a common knowledge base that can be integrated into multifunctional, actor-led landscape development. We elaborate this concept into a knowledge framework, the structure–function–value chain, and expand the current pattern–process paradigm in landscape ecology with value in this way. Subsequently, we analyse how the framework could be applied and facilitate interdisciplinary research that is applicable in transdisciplinary landscape-development processes.     

Landscape ecology: Population genetics at the metapopulation level

Distribution of genetic diversity in a landscape depends on both within and among population processes. Selective pressures within populations have traditionally been studied by population genetics, which usually assumes that populations are at equilibrium. However, when selection pressures within and among populations are different, landscape processes are required to define an equilibrium (landscape being defined as the habitat of a set of populations called a metapopulation, and populations will differ depending on their situation in the landscape, i.e. their age and the state of neighboring populations). We examine reproduction systems and life history traits, for which variation depends on landscape processes. Predictions of their states in a metapopulation are drawn from theoretical models, and confronted to observations collected in natural populations.     

Landscape ecology of uncultivated lowlands in Central Spain

The relationship between groundwater and landscape in representative areas of the Spanish plateaux is discussed, with special attention given to the Douro River basin. The study focusses on the transference of water and matter that is conditioned by groundwater flow systems, and also on water bodies, wet meadows, marshes, saline soils under their influence.These factors are of great importance in semiarid areas. Using photointerpretation, interviews, vegetation plots, water samples from wells and springs and soil samples, and the results of data processing (principal component analysis, shared information) we find that hydrological processes are the main controlling factor in the ecological function and variation of uncultivated lowlands. These processes include the alternation of recharge and discharge areas, the geochemical evolution of groundwater and the independent flows of the regional system.The landscapes in recharge and discharge areas are compared, as well as the influence of the evolutionary stage of the groundwater in the latter areas (glycophyte or halophyte vegetation). After observing the ecological importance of these aquifer discharges systems, the causes of their accelerated transformation are analyzed.     

Impacts of road corridors on urban landscape pattern: a gradient analysis with changing grain size in Shanghai, China

Urbanization is one of the most important driving forces for land use and land cover change. Quantifying urban landscape pattern and its change is fundamental for monitoring and assessing ecological and socioeconomic consequences of urbanization. As the largest city in the country, Shanghai is now the fastest growing city in China. Using land use data set of 2002 and combining gradient analysis with landscape metrics, we analyzed landscape pattern of Shanghai with increasing grain size to study the impacts of road corridors on urban landscape pattern. Landscape metrics were computed along a 51×9 km² transect cutting across Shanghai with a moving window. The results showed that the urban landscape pattern of Shanghai was greatly changed when road corridors were merged with urban patches and the variation of patch density would alter when grain size changed. As a linear land use type, road corridors exhibited a different spatial signature comparing with other land use types and distinctive behavior with increasing grain size. Merging road and urban patches resulted in a sharp reduction in patch density, mainly caused by segmentation of roads corridors. The results suggested that grain size around 7.5 m might be optimal for urban landscape analysis. Landscape patch density is significantly correlated with road percent coverage and the most important effect of road corridors in urban landscape is increased habitat fragmentation.     

The importance of integrating landscape ecology in habitat models: isolation-driven occurrence of north island robins in a fragmented landscape

Although the role of habitat fragmentation in species declines is well recognised, the effect of habitat quality on species distributions is often studied using presence–absence models that ignore metapopulation dynamics. We compared three approaches to model the presence–absence of North Island robins in 400 sites among 74 fragments of native forest in a 15,000-ha agricultural landscape in New Zealand. The first approach only considered local habitat characteristics, the second approach only considered metapopulation factors (patch size and isolation), and the third approach combined these two types of factors. The distribution of North Island robins was best predicted by patch isolation, as their probability of occurrence was negatively correlated with isolation from neighbouring patches and from the closest major forests, which probably acted as a source of immigrants. The inclusion of habitat factors gave only a slight increase in predictive power and indicated that robins were more likely to occur in areas with tall canopy, tall understory and low density of young trees. We modelled the effect of isolation using an index of functional patch connectivity based on dispersal behaviour of radio-tracked juveniles, and this functional index greatly improved the models in comparison to classical indices relying on Euclidean distances. This study highlights the need to incorporate functional indices of isolation in presence–absence models in fragmented landscapes, as species occurrence can otherwise be a misleading predictor of habitat quality and lead to wrong interpretations and management recommendations.