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T. Höbinger et al. 2010. Impact of changing cultivation systems on the landscape structure of La Gamba
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Impact of changing cultivation systems on the landscape structure of
La Gamba, southern Costa Rica
Tamara Höbinger 1* , Stefan Schindler 1 & Anton Weissenhofer 2,3
1 Department of Conservation Biology, Vegetation & Landscape Ecology, Faculty of
Life Sciences, University of Vienna, Rennweg 14, A-1030 Vienna, Austria
2 Department of Structural and Functional Botany, Faculty of Life Sciences, University
of Vienna, Rennweg 14, A-1030 Vienna, Austria
3 Tropical Station La Gamba, Postal 178, Golfito/Puntarenas, Costa Rica
Abstract
Human activities often cause changes and homogenization in landscape structure. To investigate
the human impact on a tropical agricultural landscape we mapped land cover and small-scale
linear landscape elements in La Gamba (Costa Rica) and compared eight sections by different
landscape metrics. Rural sections clearly differed from forests, especially pasture-dominated
sections including many linear landscape elements and few big plantations. The largest and
most compact patches belonged to primary and secondary forests. Conversely, cultivated
landscapes were diverse comprising many small patches. Contrasting the results of other
studies, most rural sections obtained higher fractal dimensions than forests, probably due to a
higher density of linear landscape elements. Natural landscape elements such as live fences and
riparian vegetation which are supporting wildlife movement between forests are declining. Their
protection is of major importance, particularly as the globally increasing cultivation of oil palms
is significantly altering the countryside of La Gamba and many other tropical land mosaics.
Keywords: Costa Rica, Habitat fragmentation, La Gamba, Landscape metrics, Land use
1. Introduction
Nowadays biodiversity is highly threatened by human activities in all tropical regions of the
world (Kappelle et al. 2003). The loss and fragmentation of tropical forests and rapid changes in
land use have great influence on the population dynamics of various native plant and animal
species (e.g. Morera et al. 2005; Harvey et al. 2008b). By improving the ecological connectivity
between forest patches and natural landscape elements in agricultural areas the problem of
habitat fragmentation can be alleviated (Morera et al. 2005). Therefore, the presence of natural
landscape elements, such as live fences, forest patches and gallery forests is of great importance
for wildlife using cultivated areas (Harvey et al. 2005, 2008a; Seaman and Schulze 2009).
The village “La Gamba” is situated at the edge of the Piedras Blancas National Park (southwest
Costa Rica) and its agricultural area belongs to a zone that is important for wildlife exchange
between forest areas. Since the founding of the village in the 1940s its economy has undergone
several changes. Cattle breeding and rice production have always been important and large areas
were deforested to gain farmland. From 1954 to 1961 bananas were the most common cash crop
in La Gamba. During the great depression in the 1980s many plantations were abandoned, rice
fields and pastures remained as the most common forms of land use (Klingler 2007). Nowadays
* Corresponding author. Tel.: 0043-660-2568808
Email address: t.hoebinger@gmail.com
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.