Collaborative landscape research in Reunion Island: Using spatial modelling and simulation to support territorial foresight and urban planning

This paper reflects on collaborative landscape research conducted in Reunion Island, an outermost region of the European Union. On this 2,500 km² tropical island also considered a major international biodiversity hotspot, land-use planners must address important challenges, especially growing population densities and urban sprawl that cause important pressure on agricultural land and natural ecosystems. While progress has been made towards land-use zoning and planning at the island scale, entrenched interests and a lack of communication between the agricultural, urban and environmental sectors continue to hinder the design and implementation of integrated land-use plans at the local level. This paper presents an approach to territorial foresight where urban development scenarios and spatial models were co-constructed with a collective of institutional actors in order to facilitate dialogue on future urbanization patterns and impacts on landscapes. It describes how spatially explicit models and simulations of urban development, first used as demonstrators, have raised individual interests and expectations and facilitated the structuring of a collaborative research network. Models and scenarios were then questioned, redesigned collectively and used as boundary objects to facilitate a shift away from statistical and sectorial readings towards more territorialized and integrated perspectives. Analysing inputs, reactions and feedback from the actors involved in the research, this paper discusses the role and potential value of landscape modelling and simulation in mediating debates among planning stakeholders and creating social learning situations.     

Comparison of input data with different spatial resolution in landscape pattern analysis – A case study from northern Latvia

A suitable spatial scale needs to be selected in geographical and landscape ecological research, and this requires great consideration as different scales have profound effect on derived landscape spatial patterns. Numerous studies have investigated the effects of different scales on landscape metrics using simulated patterns, but few have been conducted to compare different data sources with variable scale for regional- and landscape-scale assessments. Possibly this has occurred because researchers have been prone to use the best available source, a well-known standard, and easiest to use. This study was conducted to assess the impact of input data resolution on values of landscape pattern metrics in four landscapes at scales 1:10 000, 1:50 000 and 1:100 000. The aim was to determine the applicability of three data sources for thematic models in landscape pattern analyses in the Eastern Baltic region. We found that the utility of CORINE Land Cover data for comprehensive structural assessment in mosaic-type landscapes was very limited, as the level of cartographic generalization excluded many small and linear landscape structure elements with potentially high importance for landscape functioning, such as habitat continuity. We also found that actual area harvested using clearcuts was considerably higher than shown in CORINE data, due to clearcuts size being much smaller than the minimum mapping unit. In the light of this, we suggest using data with spatial resolution corresponding to a cartographic scale of at least 1:50 000, in cases when spatial patches have size up to 25 ha.     

Land changes in Slovakia: Past processes and future directions

The aim of this study is to bring a unique overview of past, current and plausible future land use development in Slovakia. The study assessed land change processes and their spatial determinants related to the most significant socio-political periods that have shaped the former socialist country over the past 30 years, namely, socialism (1980–1990), postsocialism (1990–2000), EU accession (2000–2006), EU membership (2006–2012). Using boosted regression trees, the impact of different biophysical, socioeconomic, policy and distance-based factors was evaluated on land transitions, categorised as urbanisation, agricultural intensification and extensification, afforestation, deforestation and forest disturbance (natural and management-induced). Results show significant shifts in the landscape management associated with the institutional changes, especially in the postsocialist period.Agricultural intensification, which dominated the socialist period, was in subsequent periods substituted by afforestation and agricultural extensification. High relative annual rates of forest disturbance have dominated land-use change over the past 30 years, while deforestation was a minor land-use change during the late socialist period. Urbanisation has played a significant role and changed considerably through the studied periods: high urbanisation rates under socialism, a massive decline in the postsocialism and EU accession periods and increasingly high urbanisation rates during the EU membership period.Taking into account national and international (EU related) demands, we assessed land use development for 2040 within five different future land use scenarios. These scenarios were characterised as either extensions of current development trends, or as developments along axes that target globalisation or regionalisation, and more or less intervention. Results show that afforestation is by far the land-change process that will have the greatest impact on future Slovakian landscapes, mostly in rural areas. Among changes in agriculture, all scenarios uniformly suggest that extensification will exceed intensification mostly at the cost of arable land. In addition, urban areas will expand at the expense of arable land, particularly in the accessible city hinterlands.     

Exploring a combination of objective and subjective assessment in landscape classification: Side case from Turkey

Landscape is a product of interactions between human and nature that bring multiple characteristics to discrete geographic settings. Landscape character assessment (LCA) is a process of describing, mapping and evaluating distinct characters in the landscape. The aim of this study is to integrate objective and subjective assessment in landscape classification in the case of Side district in Antalya, Turkey. The methodology of the study is based on a holistic approach to combine map-based biophysical information and on-site visual landscape characteristics into the LCA process. Principal component and cluster analysis were used to understand relationships and spatial patterns between 29 landscape character areas and types which were previously defined by previous work. The main source of data was landscape characters, and 35 character attributes was processed as variables. Cluster analysis showed that landscape character areas and types in Side were gathered into two main cluster groups and five sub clusters. The majority of landscape character areas tended to constitute separate subclusters, while character types appeared to form large groups of clusters in which recognisable land-use patterns were the main activity. According to the cluster dendrogram, it was possible to interpret spatial linkages between the clusters of character areas and types and to delineate geographic classification of the main landscapes in Side. Scaling relations for LCA in a pattern-process-product framework provided an explicit understanding of the data layers in landscape classification and where the clustering can function. Biophysical characteristics comprised the pattern of the landscape, while visual characteristics demonstrated the condition of the landscape as a product. The process depends upon transformation between the objective and the subjective as a link between pattern and product. Further steps would be to conduct semistructured surveys to assess local perceptions and preferences about landscape characters for landscape quality objectives.     

Landscape persistence and stakeholder perspectives: The case of Romania's Carpathians

The traditional use of land for food, fuel and wood created cultural landscapes, which are threatened across Europe. The factors which contributed to their endangerment need to be identified to achieve effective preservation of such landscapes. The aim of our study was to identify landscapes with historical persistence in a GIS-based comparative analysis of historical and contemporary maps and the most prominent causes of the past landscape changes, based on stakeholders' perspective. We considered a case study in Romania's Carpathians. Three major land cover types were extracted from maps dating from 1912, 1980 and 2009: built-up, pastures and forests. The historical persistence of all land cover types was poor (<20%) and profound changes were quantitatively confirmed. Large, compact patches of unchanged forests were located in the neighbourhood of a national park. The persistent pastures were situated close to human settlements, and their preservation can be related to local traditional agro-silvo-pastoral management. Although the built-up area has increased over time, the corresponding surfaces are small and consist of scattered patches located around historical monuments. Semi-structured interviews were conducted to investigate stakeholders' perspective. Using cluster analysis five prominent causes of past landscape changes are identified: 'increasing tourism', 'land tenure and social changes', 'land-use intensification', 'post-communist transition', and 'foreign investments'. We join the results of the GIS analysis with those from stakeholders' perspective to gain more insights into the landscape changes. This research offers important information that could be used for the further planning of these valuable cultural landscapes in order to avoid potential conflicts and degradation.     

Measuring and monitoring linear woody features in agricultural landscapes through earth observation data as an indicator of habitat availability

The loss of natural habitats and the loss of biological diversity is a global problem affecting all ecosystems including agricultural landscapes. Indicators of biodiversity can provide standardized measures that make it easier to compare and communicate changes to an ecosystem. In agricultural landscapes the amount and variety of available habitat is directly correlated with biodiversity levels. Linear woody features (LWF), including hedgerows, windbreaks, shelterbelts as well as woody shrubs along fields, roads and watercourses, play a vital role in supporting biodiversity as well as serving a wide variety of other purposes in the ecosystem. Earth observation can be used to quantify and monitor LWF across the landscape. While individual features can be manually mapped, this research focused on the development of methods using line intersect sampling (LIS) for estimating LWF as an indicator of habitat availability in agricultural landscapes. The methods are accurate, efficient, repeatable and provide robust results. Methods were tested over 9.5 Mha of agricultural landscape in the Canadian Mixedwood Plains ecozone. Approximately 97,000 km of LWF were estimated across this landscape with results useable both at a regional reporting scale, as well as mapped across space for use in wildlife habitat modelling or other landscape management research. The LIS approach developed here could be employed at a variety of scales in particular for large regions and could be adapted for use as a national scale indicator of habitat availability in heavily disturbed agricultural landscape.     

Cosmogenic isotope (Cl) surface exposure dating of the Norber erratics, Yorkshire Dales: Further constraints on the timing of the LGM deglaciation in Britain

Cosmogenic isotope (³⁶Cl) surface exposure dating of four of the erratic boulders at Norber in the Yorkshire Dales National Park, northwest England, yielded mean ages of ∼22.2 ± 2.0 ka BP and ∼18.0 ± 1.6 ka BP for their emplacement. These two mean values derive from different ³⁶Cl production rates used for exposure age calculation. The ages are uncorrected for temporal variations in production rates and may underestimate the true ages by 5-7%. The former age, although implying early deglaciation for this area of the British ice sheet, is not incompatible with minimum deglaciation ages from other contexts and locations in northwest England. However, the latter age is more consistent with the same minimum deglaciation ages and geochronological evidence for ice-free conditions in parts of the northern sector of the Irish Sea. Within uncertainties, the younger of the mean ages from Norber may indicate that boulder emplacement was associated with North Atlantic Heinrich event 1. The limited spatial (downvalley) extent of the Norber boulders implies that at the time of their deposition the ice margin was coincident with the distal margin of the erratic train. Loss of ice cover at Norber was followed by persistent stadial conditions until the abrupt opening of the Lateglacial Interstadial when large carnivorous mammals colonised the area. The ³⁶Cl ages are between ∼3.0 ka and ∼13.0 ka older than previous estimates based on rates of limestone dissolution derived from the heights of pedestals beneath the erratics.     

The conversion of natural riparian forests into agricultural land affects ecological processes in Atlantic forest streams

Agricultural practices affect the integrity of riparian areas of small streams. In this study we tested the hypothesis that the increase of agricultural activities influences negatively the functional conditions of the low order streams in the Atlantic forest of southern Brazil. Litter bags with leaves of Nectandra megapotamica (Spreng.) Mez were located in eight streams with different amounts of woody vegetation and agriculture land uses in their riparian zones. After 7, 15 and 30 days, the litter bags were removed for identification of associated invertebrates and determination of decomposition rate. Decomposition rates were negatively influenced by agriculture in the riparian zone while primary production was positively influenced. On the other hand, the decomposition mediated by microorganisms did not vary along the degradation gradient. The abundance of collectors increased in streams adjacent to agricultural land while the abundance of shredders was decreased. Our results showed that algae biomass and leaf decomposition were sensitive to the replacement of native vegetation by agricultural use. However, the trophic structure of invertebrates was moderately sensitive to agricultural land use.     

Post-glacial rock weathering processes on a roche moutonn@e in the Riksgränsen area (68°N), northern Norway

Weathering processes responsible for landscape denudation in Arctic environments are poorly understood. Traditionally, gelifraction has been widely invoked as the dominant weathering process, but empirical support for this is frequently lacking. In Norwegian Lapland, post-glacial weathering has been recently attributed to predominantly biophysical processes, based on field measurements of landscape lowering undertaken by André (1995). The study reported here examined bedrock samples from one of André's sites for mineralogical and chemical transformations since post-glacial exposure. Backscatter scanning electron microscopy reveals extensive mineral grain dissolution and accompanying development of rock porosity. Wavelength dispersive spectroscopy shows these mineral alterations to be the result of the loss of major chemical constituents including Ca, Mg, K, Si, and Al. Chemical weathering is clearly a component of post-glacial landscape denudation in Norwegian Lapland, in addition to the important role of biophysical processes identified by André (1995). Cosmogenic dating of the sampled bedrock surface confirms that much of this weathering has occurred in the last 10,000 years.     

Spatio-temporal pattern analysis of land use/cover change trajectories in Xihe watershed

Human-induced land use/cover change has been considered to be one of the most important parts of global environmental changes. In loess hilly and gully regions, to prevent soil loss and achieve better ecological environments, soil conservation measures have been taken during the past decades. The main objective of this study is to quantify the spatio-temporal variability of land use/cover change spatial patterns and make preliminary estimation of the role of human activity in the environmental change in Xihe watershed, Gansu Province, China. To achieve this objective, the methodology was developed in two different aspects, that is, (1) analysis of change patterns by binary image of change trajectories overlaid with different natural geographic factors, in which Relative Change Intensity (RCI) metric was established and used to make comparisons, and (2) analysis based on pattern metrics of main trajectories in the study area. Multi-source and multi-temporal Remote Sensing (RS) images (including Landsat ETM+ (30 June 2001), SPOT imagery (21 November 2003 and 5 May 2008) and CBERS02 CCD (5 June 2006)) were used due to the constraints of the availability of remotely sensed data. First, they were used to extract land use/cover types of each time node by object-oriented classification method. Classification results were then utilized in the trajectory analysis of land use/cover changes through the given four time nodes. Trajectories at every pixel were acquired to trace the history of land use/cover change for every location in the study area. Landscape metrics of trajectories were then analyzed to detect the change characteristics in time and space through the given time series. Analysis showed that most land use/cover changes were caused by human activities, most of which, under the direction of local government, had mainly led to virtuous change on the ecological environments. While, on the contrary, about one quarter of human-induced changes were vicious ones. Analysis through overlaying binary image of change trajectories with natural factors can efficiently show the spatio-temporal distribution characteristics of land use/cover change patterns. It is found that in the study area RCI of land use/cover changes is related to the distance to the river line. And there is a certain correlation between RCI and slope grades. However, no obvious correlation exists between RCI and aspect grades.