A Landscape Ecology Approach to Assessing Development Impacts in the Tropics: A Geothermal Energy Example in Hawaii

Abstract

Geographic information systems (GIS) are increasingly being used in environmental impact assessments (EIA) because GIS is useful for analysing spatial impacts of various development scenarios. Spatially representing these impacts provides another tool for landscape ecology in environmental and geographical investigations by facilitating analysis of the effects of landscape pattern on ecological processes and examining change over time. Landscape ecological principles are applied in this study to a hypothetical geothermal development project on the Island of Hawaii. Some common landscape pattern metrics were used to analyse dispersed versus condensed development scenarios and their effect on landscape pattern. Indices of fragmentation and patch shape did not appreciably change with additional development. The amount of forest to open edge, however, greatly increased with the dispersed development scenario. In addition, landscape metrics showed that a human disturbance had a greater simplifying effect on patch shape and also increased fragmentation than a natural disturbance. The use of these landscape pattern metrics can advance the methodology of applying GIS to EIA.

Geothermal Energy as an Indigenous Alternative Energy Source in BC

“…This study showed that the ecological effect of condensed versus dispersed development was important in Hawaii because of problems posed by the invasion of exotic species. The loss of a native plant canopy can result in a greater number of introduced birds at the expense of the native ones (Griffith et al 2002). Despite British Columbia's more diverse array of ecosystems, which support a greater variety of plant and animal species, similar ecological effects could be experienced here.…”

“…Although geologists may characterize geothermal energy developments as having relatively small footprints, a typical site consists of exploratory wells for numerous temperature gradients to measure subsurface temperature, deep slim-hole wells, several full-diameter wells, areas for the drill rig, a holding pond for water to quench potential well blowouts, a service yard for storage of equipment, and access roads (Griffith et al 2002;Meager Creek Development Corporation 2004). Pipelines and vessels are required to transport steam from the well-heads to the power plant, and transmission lines are needed to transmit the produced power from the power plant to substations (Meager Creek Development Corporation 2004).…”

“…Environmental impact assessment is essential to identify and mitigate impacts of development on vegetation, wildlife, and their habitats (Environmental Assessment Office 2005). Important landscape parameters, such as edge and patch sizes, should also be included in the assessment because land clearing for roads, transmission lines, and development can create openings for exotic-species invasions into adjacent vegetation (Griffith et al 2002). Controlling edge effect also is critical in British Columbia, where many of the sites identified for geothermal resources are in the natural state, and are within the traditional territories of First Nations people (Fairbank & Faulkner 1992).…”

Analyses of urban landscape dynamics using multi-temporal satellite images: A comparison of two petroleum-oriented cities

“…[P i ln(P i )] P i : percentage of class; n: number of landscape classes It measures the landscape diversity (O'Neill et al, 1988;Viedma and Melia, 1999) Contagion index CONT = 1 + m i=1 n j=1 P ij ln(P ij )/2 ln(n) P ij = P i P j/i , P j/i = m ij /m i P ij : probability that a patch of ith class adjacent to jth class; m: patch number of ith class; n: number of landscape classes; P i : randomly chosen probability; P j/i: conditional probability A large CONT reflects the clumping of large contiguous patches while a small CONT value reflects a landscape that is dissected into small patches (O'Neill et al, 1988;Turner, 1990;Li and Reynolds, 1993;Griffith et al, 2002) Mean Although grassland was the dominant class in both Houston and Daqing, it experienced a rapid decrease in its mean patch area in these two cites. In Houston, it decreased from 0.12 km 2 /each to 0.01 km 2 /each in 1990 and 2000.…”

Dynamic Analysis of Urban Landscape Patterns of Vegetation Coverage Based on Multi-temporal Landsat Dataset

“…Conversely, remote sensing has facilitated extraordinary advances in analyzing urban vegetation coverage changes by its real-time and wide coverage features, which has become a significant measurement for monitoring the urban ecological environment. In recent years, different ecological problems have appeared in urban regions, and some landscape ecology approaches to combining remote sensing have been applied to explore the urban landscape pattern and its change process [6][7][8][9]. Tang et al linked spatial pattern and biophysical parameters of urban vegetation by multi-temporal Landsat imagery [10].…”