Land cover dynamics modelling in Karla basin, Greece
C.A. Chatzipetrou1* and C. Napoléone2
1 University of Thessaly, School of Agricultural Sciences, Department of Agriculture Crop Production and Rural Development, Laboratory of Biometry, Fytokoy Str, 384 46 N.Ionia, MagnisiaVolos, Greece, E-mail: email@example.com
2 INRA Ecodeveloppement UR0767, INRA Domaine Saint-Paul – Site Agroparc 228 route de l’Aérodrome CS40509 F-84914, Avignon cedex 9, France. E-mail: firstname.lastname@example.org
In the context of the significant changes of land cover in Mediterranean peri-urban areas, policies addressing directly the integrated management of landscapes are important. Geographical and socio-economic disparities, public projects, continuous pressure on land resources and intensive arable farming lead to ecosystem perturbation, to agricultural landscape degradation and involve conflicts and challenges for local communities (FAO,2011). Rural development is essential to harmonize agriculture practices with nature protection i.e. maximizing the food production while maintaining the natural richness of the landscapes.
In Greece, a north Mediterranean country, the experiences of the developing rural practices with respect to the environment show some successes but the aspect of the not exploited local community and the lack of vertical and horizontal integration in the administrative structure jeopardize their future (Pediatidi, 2010).
This research aims to model land cover dynamics in the region of Karla basin, a rural and a nature protection area, in the geographic department of Thessaly in central Greece. The final output of the research is expected to be a method to identify where and how the rural development in the region is heading in the next years.
Materials and Methods
View to decide an appropriate management of land use, quantification and prioritization of provided ecosystem services must take into account the effects of land use and human activity at different scales (Marchamalo et al. 2011). Our study objective is to analyze the changes of land use and predict land cover dynamics in Karla basin in the next 20 years, based on physical characteristics of the land as soil and water quality, Natura 2000 data, and socio-economic factors as income, gender, education by questionnaires results. Our hypothesis is “the Karla basin is susceptible to desertification”.
To visualize and mapping capabilities which facilitate the creation of land suitability map we use a GIS-based environment. Additionally, we integrate the Analytical Hierarchy Process (AHP) (Vaidya and Kumar, 2006) and the Weight of Evidence (WoE) (Agterberg, and Bonham-Carter, 1990) multi-criteria methods for combining evaluated data in support the hypothesis. A pair of weights for each variable will be calculated and values will be presented on thematic maps. The output from weights will be used to estimate the probability that new point locations on the assessed area would added on the map built on the presence or absence of each variable. Thus, the values of probability will change with the choice of unit cell area – a transition matrix for subdivision of the area into a grid of cells is used where each cell stores a numeric value representing a variable for that unit of space – when the grid is drawn as a map, cells are assigned colors according to their numeric values (ESRI, n.d.).
The steps for the mapping process are: creation of a digital spatial database, a prediction of sensitivity in desertification based on the area exploration datasets, calculation of weights for each predicted map, interpretation of results in connection to our hypothesis (figure 1).
For GIS data processing and modelling are needed land cover and topographic maps of the study area, drivers of land cover change as distance to roads, distance to water bodies, soil salinity, water quality, socio-economic and legislative data (GDP indicator, population growth rate, EU nature protected area). The maps of the years 1990 and 2012 were selected as the basis to analyze the land cover changes according their accuracy and their similarity in mapping parameters. The land cover types selected for this study were, cultivated land, grassland, water body and build-up area. Quantifying the extend of each land cover type using the Weight of Evidence technique and displaying magnitude of land cover change in land cover maps will simulate the trends of land cover in the study area for the next 20 years.
The final results of the study will demonstrate if Karla basin is undergoing desertification. Our method may be a critical reference to make management decisions, to revert the rural land degradation while preserving the high natural and scenic value of the area.
Figure 1. Research methodology (click to enlarge the figure)
Agterberg, F.P. and Bonham-Carter, G.F., (1990). “Deriving weights of evidence from geoscience contour maps for the prediction of discrete events: Proceedings 22nd APCOM Symposium”, Berlin, Germany, v.2, p. 381-395.
ESRI documentation, Retrieved from the official site of ESRI (n.d.) http://support.esri.com/other-resources/gis-dictionary/term/ESRI%20Grid
FAO, (2011). “The state of the world’s land and water resources for food and agriculture – Managing systems at risk”, Book, ISBN 978-1-84971-326-9.
Marchamalo, M., R. Vignola, F. Gomez-Delgado, B. Gonzalez-Rodrigo (2011). “Quantifying Services and Identifying Watershed Priority Areas for Soil and Water Conservation Programmes”, Book: Ecosystem services from agriculture and agroforestry: measurement and payment / Bruno Rapidel … [et al.]. ISBN 978-1-84971-147-0
Pediatidi, K. (2010). “Actions for the conservation of coastal dunes with JUNIPERUS spp. in Crete and the south Aegean (Greece)”, LIFE07NAT/GR/000296, JUNICOAST, pp. 1-70
Vaidya, O.S. and S. Kumar, (2006). “Analytic hierarchy process: An overview of applications”, European Journal of Operational Research, Vol.169, pp. 1–29