Rohan Fisher

Patterns of landscape fire and predicted vegetation response in the North Kimberley region of Western Australia

The paper reports on the development of a decadal fire history, 1990–1999, derived from Landsat imagery, and associated assessment of landscape-scale patterns, in a remote, sparsely human-populated region of the high rainfall zone of monsoonal north-western Australia. The assembled fire history confirms observations, derived from coarser-scale imagery, that substantial areas of the North Kimberley are burnt each year. The annual mean extent of burning was 31% (albeit involving marked inter-annual variability), with most burning occurring in the latter part of the dry season under relatively severe fire weather conditions. Extent of burning was found to be associated with intensity of landuse; most burning occurred on pastoral lands, particularly in association with more fertile basalt soils. Based on previous modelling studies, predicted effects of contemporary fire regimes include increased development of woody regeneration size-classes, especially on non-basalt substrates. In contrast, on sandstone-derived substrata, fire interval data indicate that longer-lived obligate-seeder shrub species are likely to be suppressed and ultimately displaced by contemporary fire regimes. Such observations are supported by recent evidence of regional collapse of the long-lived obligate seeder tree species, Callitris intratropica. Collectively, assembled data point to the need to undertake a thorough appraisal of the status of regional biota in this remote, ostensibly ecologically intact region.

Free and simple GIS as appropriate for health mapping in a low resource setting: a case study in eastern Indonesia

BackgroundDespite the demonstrated utility of GIS for health applications, there are perceived problems in low resource settings: GIS software can be expensive and complex; input data are often of low quality. This study aimed to test the appropriateness of new, inexpensive and simple GIS tools in poorly resourced areas of a developing country. GIS applications were trialled in pilot studies based on mapping of health resources and health indicators at the clinic and district level in the predominantly rural province of Nusa Tenggara Timur in eastern Indonesia. The pilot applications were (i) rapid field collection of health infrastructure data using a GPS enabled PDA, (ii) mapping health indicator data using open source GIS software, and (iii) service availability mapping using a free modelling tool.ResultsThrough contextualised training, district and clinic staff acquired skills in spatial analysis and visualisation and, six months after the pilot studies, they were using these skills for advocacy in the planning process, to inform the allocation of some health resources, and to evaluate some public health initiatives.ConclusionsWe demonstrated that GIS can be a useful and inexpensive tool for the decentralisation of health data analysis to low resource settings through the use of free and simple software, locally relevant training materials and by providing data collection tools to ensure data reliability.

Remote sensing of fire regimes in semi-arid Nusa Tenggara Timur, eastern Indonesia: current patterns, future prospects

Substantial areas of eastern Indonesia are semi-arid (with a pronounced dry season extending from April to November) with extensive areas of uncultivated vegetation dominated by savanna grasslands and woodlands. These are highly fire-prone, despite high population densities reliant on intensive subsistence agriculture and an official national fire policy that prohibits all burning. To date, no regional studies have been undertaken that reliably assess the seasonal extent and patterning of prescribed burning and wildfire. Focusing on two case studies in east Sumba (7000 km2) and central Flores (3000 km2) in the eastern Indonesian province of Nusa Tenggara Timur, the present paper addresses: (1) the efficacy of applying standard remote sensing and geographic information system tools as developed for monitoring fire patterns in savanna landscapes of adjacent northern Australia, for (2) describing the seasonal patterning of burning at village and broader regional scales in 2003 and 2004. Despite recurring cloudiness, which significantly affected daily fire detection of ‘hotspots’ from Advanced Very High Resolution Radiometer and Moderate Resolution Imaging Spectroradiometer sensors, fire mapping from Landsat imagery was undertaken successfully to reveal: (1) fires burnt an annual average of 29% of eastern Sumba (comprising mostly grassland savanna), and 11% of central Flores (with large forested areas); (2) most fire extent occurred in savanna grassland areas, and significantly also in cultivated lands and small remnant patches of forest; (3) most fire activity occurred under harsh, late dry season conditions; and (4) while the great majority of individual fires were less than 5 ha, some late dry season fires were hundreds of hectares in extent. The potential routine application of different image sensors for fire mapping and hotspot detection is considered in discussion.

Tropical forest monitoring, combining satellite and social data, to inform management and livelihood implications: Case studies from Indonesian West Timor

Abstract Deforestation in the worlds tropics is an urgent international issue. One response has been the development of satellite based monitoring initiatives largely focused on the carbon rich forests of western Indonesia. In contrast this study focuses on one eastern Indonesian district, Kabupaten Kupang, which has some of the largest and least studied tracts of remaining forest in West Timor. A combination of remote sensing, GIS and social science methods were used to describe the state of forests in Kabupaten Kupang, how and why they are changing. Using satellite imagery, case studies and on-ground interviews, this study explores the proposition that transdisciplinary local social, cultural and biophysical knowledge is important for effectively using remotely sensed data as a tool to inform local management policies. When compared to some other parts of Indonesia, the rate and extent of deforestation in West Timor was found to be relatively small and a satellite based assessment alone could conclude that it is not a critical issue. However this study showed that when on-ground social data are coupled with (such) satellite-based data a more complex picture emerges, related to key livelihood issues. The causes of forest cover change were found to be multivariate and location specific, requiring management approaches tailored to local social issues. This study suggests that integrative research can maximise the utility of satellite data for understanding causation and thus informing management strategies. In addition, the satellite based assessment found that at the time of the study less than 4% of forested land was within national parks and nature reserves and less than a third of the protected catchment forest zone was forested. These data suggest considerable scope for upland re-forestation activities or the redrawing of protected forest boundaries.

Creating a Sediment Budget in a Data Poor Context: An Example from Eastern Indonesia

Abstract Sediment budgets are useful in informing catchment management, however the resources and data required to create a sediment budget may be prohibitive, particularly in developing countries. This paper presents a multidisciplinary approach to an investigation of sediment sources and the creation of a first‐order sediment budget for a catchment in eastern ndonesia: a data‐poor region in the wet‐dry tropics with high sediment production rates and a population largely dependent on subsistence agriculture. The approach integrates results from geospatial analysis and key informant interviews and radionuclide tracers. Free software and imagery were used to demonstrate that geospatial analysis can be achieved without high costs. Surface soil erosion rates were mapped using the Revised Universal Soil Loss Equation, and subsoil sediment sources were digitised from high‐resolution imagery. Key informant interviews identified additional gully erosion, not detected through spatial analysis. Radionuclide tracers 137s, 210b(ex) and 239u were used to determine the relative contributions of surface soil to sediment. The main sediment sources in the Kambaniru catchment were surface soils (31%), channel change (22%), gully erosion (8%), and landslides (1%), with an estimated annual sediment load of 1 440 000 t yr−1 at the weir. This sediment budget showed subsoils were a major source of sediment, which contradicts assumptions that underpin Indonesian catchment management policies. The geospatial, interview and field methods were effective in identifying, mapping and quantifying subsoil sediment sources, and can readily be applied in areas where data are scarce and technical skills are low. Radionuclide tracers provide essential information but are expensive.

Post-project evaluation of the sustainability of development project outcomes: a case study in eastern Indonesia

The extent to which project outcomes are sustained years after development projects have ended is not routinely investigated. This study assessed the long-term impacts of a fire management project in eastern Indonesia seven years after the funding ended. Post-project evaluation increased understanding of the factors determining sustainability of project outcomes and links to development impacts. The continuation of community fire management and agroforestry groups was linked to demonstration of benefits to farmers and multi-level engagement. Activities had ceased where ownership was disputed. Some long-term impacts were outside the original aims of the fire project, including district government agencies applying fire mapping skills to other development issues.

Interactive, open source, travel time scenario modelling: tools to facilitate participation in health service access analysis

BackgroundModelling travel time to services has become a common public health tool for planning service provision but the usefulness of these analyses is constrained by the availability of accurate input data and limitations inherent in the assumptions and parameterisation. This is particularly an issue in the developing world where access to basic data is limited and travel is often complex and multi-modal. Improving the accuracy and relevance in this context requires greater accessibility to, and flexibility in, travel time modelling tools to facilitate the incorporation of local knowledge and the rapid exploration of multiple travel scenarios. The aim of this work was to develop simple open source, adaptable, interactive travel time modelling tools to allow greater access to and participation in service access analysis.ResultsDescribed are three interconnected applications designed to reduce some of the barriers to the more wide-spread use of GIS analysis of service access and allow for complex spatial and temporal variations in service availability. These applications are an open source GIS tool-kit and two geo-simulation models. The development of these tools was guided by health service issues from a developing world context but they present a general approach to enabling greater access to and flexibility in health access modelling. The tools demonstrate a method that substantially simplifies the process for conducting travel time assessments and demonstrate a dynamic, interactive approach in an open source GIS format. In addition this paper provides examples from empirical experience where these tools have informed better policy and planning.ConclusionTravel and health service access is complex and cannot be reduced to a few static modeled outputs. The approaches described in this paper use a unique set of tools to explore this complexity, promote discussion and build understanding with the goal of producing better planning outcomes. The accessible, flexible, interactive and responsive nature of the applications described has the potential to allow complex environmental social and political considerations to be incorporated and visualised. Through supporting evidence-based planning the innovative modelling practices described have the potential to help local health and emergency response planning in the developing world.