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M.B. Horta & E. Keizer 2010. Assessment of human and physical factors influencing distribution of vegetation degradation
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Assessment of human and physical factors influencing
spatial distribution of vegetation degradation -
Environmental Protection Area Cachoeira das Andorinhas, Brazil
Marise Barreiros Horta 1* & Edwin Keizer 2
1 Companhia Botânica, Brazil
2
Instituto Nacional de Pesquisas da Amazônia (INPA), Brazil
Abstract
This study examined human and physical factors influencing the spatial distribution of
vegetation degradation in a protection area. A map data set was used for the human and physical
factors investigation. Those factors comprised: roads network, rural settlements/village/city,
tourist sites, mining sites, agricultural areas, drainage, slope and geology. The vegetation
degradation diagnosis was made with utilization of five ecological indicators: cover of invasive
species, understory, canopy, bare soil and dead shrub percentage. Regression and correlation
analyses were used to investigate the relationship between vegetation degradation and factors.
The factor slope presented significantly negatively correlated to vegetation degradation in forest
areas. Distance to tourist sites showed significant negative correlation in the savannah and rocky
shrublands. Those factors can enhance humans and livestock accessibility to natural vegetation
areas, which may increase intensity of damaging activities. The information can contribute to
conservation strategies improvements in the protection area.
Keywords: vegetation degradation, change, spatially explicit factors, ecological indicators,
conservation
1. Introduction
Vegetation degradation, unlike deforestation, is not a very obvious phenomenon. The changes
are revealed gradually, sometimes not in terms of decrease of area, but represented by
qualitative losses, for example, through the reduction of species diversity, increase of invasive
species, decrease of the shrub layer, reduction of woody species and biomass decline (Hargyono
1993).
The investigations of spatially explicit factors (such as slope, roads) influencing vegetation
degradation processes rely on the fact that those factors can represent an expression to some
underlying structural driving forces, such as demographic and political forces (Mather 1990).
Most of the investigation of factors influencing vegetation degradation in the spatial context has
been directed at arid landscapes associated with land degradation, desertification and soil
erosion processes (Guerrero-Campo and Montserrat-Marti 2000, Kembron 2001). The situation
has generated studies that combine vegetation degradation with other processes, such as, soil
erosion. In general, however, they lack considerations of the quality and quantity of vegetation
(Eswaran 2001).
* Corresponding author. Tel.: 55 31 33445037; 55 31 88835937
Email address: marisehorta@companhiabotanica.com.br
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.