Papers by Anton Van Rompaey
Over the past decade, several scholars have argued that livelihood diversification in terms of of... more Over the past decade, several scholars have argued that livelihood diversification in terms of off-farm activities is key for rural households to escape from poverty in Sub-Saharan Africa (SSA). Although the continuous growth of tourism in many SSA countries has created an additional off-farm income activity, empirical evidence is lacking to substantiate the poverty alleviating impact of tourism employment as being consistent and universal at the household level. Using the case of Kibale National Park in western Uganda, the aims of this paper are (1) to analyze the actual income composition of different types of rural livelihood strategies by means of cluster analysis, and (2) to compare the financial impact of tourism employment with alternative off-farm income activities. Results show a large differentiation in income compositions of households around Kibale National Park. In general, households engaged in off-farm income activities have higher levels of overall household welfare. Tourism employment generates low incomes compared to alternative off-farm activities, but still enables households to strengthen livelihood strategies by investments in on-farm or alternative off-farm activities.
This article reports major land use changes in India's worst badland incised area. India, being a... more This article reports major land use changes in India's worst badland incised area. India, being an agriculture dependent economy, suffers a great economic loss to badlands. Strategically, it is important to know the state-of-the-art status on the dynamics of badlands. Furthermore, it is equally important to assess the processes and factors which contribute most towards it. This study, therefore, assesses the dynamics of badlands that have occurred from 1971 to 2010 using CORONA and GeoEye-1 satellite images. The study design includes 24 study plots of 1 km 2 each, covering all the dimensions of the study area. Change detection analysis which was also verified on ground revealed that the areas covered by badlands are reducing at a greater rate than badland encroachment. Badlands were reduced by 20 % in the last ca. 40 years. Factors influencing the reduction of badlands cover were studied using a logistic regression model. Five factors found to significantly influencing the reduction in badlands area are (1) distance to Chambal River, (2) distance to river channels, (3) distance to settlement, (4) slope and (5) Contributing Area. The fitted model was validated using receiver operating characteristic (ROC) curve. This study failed to find a model with good discriminative power for badland encroachment. The statistical evidence in the light of field studies indicated that badlands in populated areas are increasingly transformed into cropland.
Numerous cities in developing regions worldwide are expanding at a tremendous rate. This requires... more Numerous cities in developing regions worldwide are expanding at a tremendous rate. This requires adequate strategies to address the needs of these growing cities with diverse populations. Nonetheless, the development of urban policies is often hampered by the lack of reliable data or insight in the socio-spatial dynamics of this urban expansion. This paper therefore presents ASSURE, a spatially and temporally explicit model that can simulate urban growth and intra-urban social segregation, taking into account alternative policy strategies and expected social dynamics. The model has a flexible structure that allows incorporating specific city conditions that influence residential decision-making and adapting the simulation to the data available. This, in combination with the transparent model structure, makes ASSURE a potentially valuable decision support tool for urban planning. The potential is demonstrated with an example where the urban growth of and social segregation in Kampala (Uganda) is simulated based on (semi-)quantitative and qualitative data for ca. 800 households collected through interviews. The results of the simulations show that depending on the scenario, the spatial segregation and accessibility problems will evolve highly differently.
Conversion of tropical forests remains high on the international agenda, but the effectiveness of... more Conversion of tropical forests remains high on the international agenda, but the effectiveness of the proposed framework to reduce emissions from deforestation and degradation (REDD+) has been questioned. We hypothesized that an effective implementation of REDD+ would require understanding of the functioning of the local social-ecological system and modulation of actions to the actors' characteristics and motivations in the affected areas. But cross-scale studies of deforestation drivers are seldom performed, given the difficulties to obtain consistent datasets, particularly for the local scale. We addressed this issue for the agricultural expansion in the Central Basin of the Democratic Republic of Congo, a REDD+ priority country. We detected considerable variation in deforestation rate within scale levels, with highest variation at village and household level, which had gone unnoticed so far. Population density and market access are the main sources of inter-village variation, although cultural factors affect magnitude by an order of 2. Individual household contributions to deforestation are strongly unevenly distributed, with longer established households and better market integrated households deforesting more than others. Our results reveal that due to the current lack of cross-scale studies, policy makers are lacking context specific relevant information at local scale needed to design efficient, effective and equitable policies. They also challenge the dominant discourse that agricultural expansion in the Basin is driven by poor subsistence farmers, and make us add actor-oriented interventions and land use zoning as two crucial requirements for REDD+ intensification policies to become effective.
The present rapid urban growth of cities from developing countries causes negative externalities ... more The present rapid urban growth of cities from developing countries causes negative externalities such as lagging infrastructure development. In combination with rapidly rising motorized vehicle use this leads to severe traffic congestion affecting the mobility of the urban residents. Therefore many urban governments are planning to improve their transport and mobility situations with mass rapid transit systems of which a bus rapid transit (BRT) is a rather easy system to implement at reasonable costs. However, due to high urban inequalities the effects of urban traffic and potential improvements of the urban transport system for the diverse group of urban residents can differ significantly. In our case study Kampala (Uganda) four main groups were identified through cluster analysis of socioeconomic and residential data gathered through interviews: extreme poor, poor, middle income and rich. Each group experiences a different mobility with the extreme poor being the most vulnerable group. The planned BRT system aims to decrease the average travel time but risks to exclude the lowest income class since not enough attention is paid to the affordability of the system to all residents. Therefore we argue for a policy that works from bottom up and pays attention to the internal diversity of the population.
Quantification of forest cover is essential as a tool to stimulate forest management and conserva... more Quantification of forest cover is essential as a tool to stimulate forest management and conservation. Image compositing techniques that sample the most suited pixel from multi-temporal image acquisitions, provide an important tool for forest cover detection as they provide alternatives for missing data due to cloud cover and data discontinuities. At present, however, it is not clear to which extent forest cover detection based on compositing can be improved if the source imagery is firstly corrected for topographic distortions on a pixel-basis. In this study, the results of a pixel compositing algorithm with and without preprocessing topographic correction are compared for a study area covering 9 Landsat footprints in the Romanian Carpathians based on two different classifiers: Maximum Likelihood (ML) and Support Vector Machine (SVM). Results show that classifier selection has a stronger impact on the classification accuracy than topographic correction. Finally, application of the optimal method (SVM classifier with topographic correction) on the Romanian Carpathian Ecoregion between 1985, 1995 and 2010 shows a steady greening due to more afforestation than deforestation.
A valuable aid to assessing and managing flood risk lies in a reliable database of historical flo... more A valuable aid to assessing and managing flood risk lies in a reliable database of historical floods. In this study, a newspaper-based flood database for Shanghai (NFDS) for the period 1949–2009 was developed through a systematic scanning of newspapers. After calibration and validation of the database, Mann-Kendall tests and correlation analysis were applied to detect possible changes in flood frequencies. The analysis was carried out for three different flood types: overbank flood, agricultural waterlogging, and urban waterlogging. The compiled NFDS registered 146 floods and 92% of them occurred in the flood-prone season from June to September. The statistical analyses showed that both the annual flood and the floods in June–August increased significantly. Urban waterlogging showed a very strong increasing trend, probably because of insufficient capacity of urban drainage system and impacts of rapid urbanization. By contrast, the decrease in overbank flooding and the slight increase in agricultural waterlogging were likely because of the construction of river levees and seawalls and the upgrade of agricultural drainage systems, respectively. This OPEN ACCESS Water 2015, 7 1809 study demonstrated the usefulness of local newspapers in building a historical flood database and in assessing flood characterization.
Population growth worldwide leads to an increasing pressure on the land. Recent studies reported ... more Population growth worldwide leads to an increasing pressure on the land. Recent studies reported that many areas covered by badlands are decreasing because parts of badlands are being levelled and converted into arable land. It is important to monitor these changes for environmental planning. This paper proposes a remote-sensing based detection method which allows mapping of badland dynamics based on seasonal vegetation changes in the lower Chambal valley, India. Supervised classification was applied on three Landsat (Thematic Mapper) images, from 3 different seasons; January (winter), April (summer) and October (post-monsoon). Different band selection methods were applied to get the best classification. Validation was done by ground referencing and a GeoEye-1 satellite image. The image from January performed best with overall accuracy of 87% and 0.69 of kappa. This method opens the possibilities of using semi-automatic classification for the Chambal badlands which is so far mapped with manual interpretations only.
To date, limited attention has been paid to the role of impervious surface (IS) location in influ... more To date, limited attention has been paid to the role of impervious surface (IS) location in influencing flood processes. However, this topic is of tremendous significance for developing guidelines for urban planning and flood management. This study uses the Hydrologic Engineering Center's Hydrologic Modeling System (HEC-HMS) to investigate the impact of land-use change on flood processes and proposes a new index to quantify the impact of IS location on basin peak discharge. The results indicate that rapid urban expansion in the Longhua Basin, China, has increased peak discharge and flood volume by 140 and 162 % over the past 30 years, respectively. The new index, named the Impervious Surface Impact Index, describes the spatially varying effects of IS increase in individual sub-basins on a basin's peak discharge. For the Longhua Basin, the index varies from 0.43 in downstream sub-basins to 5.91 in upstream sub-basins. An increase in upstream IS increases peak discharge nearly 14 times more than the same increase in downstream IS. Accordingly, the location of newly created IS can influence flood processes significantly. These findings can help to find suitable locations for urban development while mitigating the impact of land development on flood risks.
Since the late 1970s, the Pearl River Delta (PRD) in China has undergone a rapid transition from ... more Since the late 1970s, the Pearl River Delta (PRD) in China has undergone a rapid transition from an agricultural landscape to a metropolitan area. The rapid urbanization has not only increased the area of impervious surfaces in the central plain; it has displaced farmland to the hilly peripheral areas. The objectives of this study are to: (1) analyze how these changes in land use in the PRD have influenced flood incidence over the past 20 years and (2) explore possible changes in flood incidence in the coming two decades. An integrated simulation of the land-use changes and the hydrological processes is employed to investigate the impact of urbanization on the volume of direct runoff. Historical flood records are used for validation. The simulation results indicate that land-use change in the PRD has markedly increased direct runoff over the past two decades. Changes in direct runoff generation and in land use are significantly correlated with historical floods at the county level. These results suggest that the increase in floods stems from the dual effect of urbanization on land use through the expansion of impervious surfaces and the displacement of farmlands to the hilly outskirts. The simulations suggest that the dual effect would continue in a future of business as usual. Stopping farmland replacement would likely reduce the increase in direct runoff generation, and this reduction would be augmented if changes in farmland replacement were combined with compact city development.
An effective removal of atmospheric and topographic effects on remote-sensing imagery is an essen... more An effective removal of atmospheric and topographic effects on remote-sensing imagery is an essential preprocessing step for mapping land cover accurately in mountain areas. Various techniques that remove these effects have been proposed and consist of specific combinations of an atmospheric and a topographic correction (TC) method. However, it is possible to generate a wide range of new combined correction methods by applying alternative combinations of atmospheric and TC methods. At present, a systematic overview of the statistical performance and data input requirement of preprocessing techniques is missing. In order to assess the individual and combined impacts of atmospheric and TC methods, 15 permutations of two atmospheric and/or four TC methods were evaluated statistically and compared to the uncorrected imagery. Furthermore, results of the integrated ATCOR3 method were included. This evaluation was performed in a study area in the Romanian Carpathian mountains. Results showed that the combination of a transmittance-based atmospheric correction (AC), which corrects the effects of Rayleigh scattering and water-vapour absorption, and a pixel-based C or Minnaert TC, which account for diffuse sky irradiance, reduced the image distortions most efficiently. Overall results indicated that TC had a larger impact than AC and there was a trade-off between the statistical performance of preprocessing techniques and their data requirement. However, the normalized difference vegetation index analysis indicated that atmospheric methods resulted in a larger impact on the spectral information in bands 3 and 4.
In the ongoing debate on the connection between tourism and poverty alleviation, tourism is often... more In the ongoing debate on the connection between tourism and poverty alleviation, tourism is often presented as a tool for poverty alleviation and the improvement of socio-economic conditions of rural communities in developing countries. Findings of prior research suggest that nature-based tourism has a positive impact; however, existing models tend to understate the spatial differentiation of impacts in different contexts. Little is known about the spatial range and scale of the benefits from tourism development at a certain location. Previous studies have shown that employment in accommodation facilities is responsible for the largest share of pro-poor impact in Ugandan tourism. This paper focuses on the spatial dimension of the impact of employment in the tourism accommodation sector on the local livelihoods, with nature-based tourism around Kibale National Park (KNP) in western Uganda as a case study. Semi-structured interviews with employees were undertaken to delineate the geographical sphere of influence (SoI) of tourism employment in the accommodation sector. Results show that tourism accommodations recruit from a small geographical sphere of influence (5-10 km) in rural settings, while in urbanized settings the sphere of influence is larger (30-40 km). Understanding spatial differences of the distribution of tourism benefits in developing countries can lead to better informed policies on poverty alleviation. Policies to promote tourism as a poverty alleviation strategy have shown some successes, but there is a danger that the spatial scale of the impact is smaller than anticipated. Furthermore, for more than 80% of households, tourism is the principal source of income. In addition, tourism employment can provide initial capital for supplementary activities, which gain in importance to the extent that their profits surpass the income from tourism employment. Tourism employment does not represent a final perspective but a stage for gathering resources and skills.
China is rapidly urbanizing and will inevitably face trade-offs between promoting economic growth... more China is rapidly urbanizing and will inevitably face trade-offs between promoting economic growth through further urbanization and protecting fertile farmland against accelerated urban expansion. This paper presents how this dilemma is being addressed in one of the most rapidly urbanizing regions in China, the Pearl River Delta (PRD), by means of assessing urban growth and farmland dynamic, as well as their complex relationships. Land use maps derived from Landsat imagery for 1990, 2000 and 2010 show a process of accelerated urban sprawl whereby built-up lands have more than quadrupled and scattered centers have merged into megacities. Nonetheless, the land use efficiency is considerably low and is declining relative to Hong Kong and Macau with respect to urban population density. On the other hand, the spreading of urban areas on farmlands causes new farmland reclamation and accelerated deforestation in the hilly surroundings. In addition, the displaced farmlands do not ensure food production because of both reclaiming farmlands on infertile lands and diversifying farming activities from grain production to market-oriented ones. The accelerated urbanization and farmland displacement are driven by profit-oriented development strategy and ineffective land use planning. Our findings demonstrate how spatial analysis can help to investigate the integrated effects of land policies on landscape.
This paper examines whether eastern Tigray is still in a phase of land degradation or if a trend ... more This paper examines whether eastern Tigray is still in a phase of land degradation or if a trend of landscape greening has started. Hitherto, the land cover in five representative Tigray villages was mapped for three different periods: 1965, 1994, and 2007. These maps were based on the interpretation of aerial photographs and high-resolution satellite imagery in combination with field validation. The results show a strong decrease of the forest and bush land in favor of arable land and rangeland from 1965 to 1994. This trend is, however, slowed down and even reversed from 1994 onwards whereby some of the arable land and rangeland are abandoned allowing shrubs and bushes to regenerate. Household interviews and census data showed that the rural population number is still increasing. However, the productivity of the farming activities did not show a significant increase. The observed abandonment of marginal farm and rangeland is, therefore, made possible only through food aid and the import of food from other regions. Furthermore, policymakers stimulate land abandonment and landscape greening by establishing exclosures.
China is rapidly urbanizing and will inevitably face trade-offs between promoting economic growth... more China is rapidly urbanizing and will inevitably face trade-offs between promoting economic growth through further urbanization and protecting fertile farmland against accelerated urban expansion. This paper presents how this dilemma is being addressed in one of the most rapidly urbanizing regions in China, the Pearl River Delta (PRD), by means of assessing urban growth and farmland dynamic, as well as their complex relationships. Land use maps derived from Landsat imagery for 1990, 2000 and 2010 show a process of accelerated urban sprawl whereby built-up lands have more than quadrupled and scattered centers have merged into megacities. Nonetheless, the land use efficiency is considerably low and is declining relative to Hong Kong and Macau with respect to urban population density. On the other hand, the spreading of urban areas on farmlands causes new farmland reclamation and accelerated deforestation in the hilly surroundings. In addition, the displaced farmlands do not ensure food production because of both reclaiming farmlands on infertile lands and diversifying farming activities from grain production to market-oriented ones. The accelerated urbanization and farmland displacement are driven by profit-oriented development strategy and ineffective land use planning. Our findings demonstrate how spatial analysis can help to investigate the integrated effects of land policies on landscape.
Despite the fact that urban farming is widespread in many African cities there is not yet a clear... more Despite the fact that urban farming is widespread in many African cities there is not yet a clearly defined view on how to deal with these activities in urban planning and management. On the basis of field interviews in the rapidly expanding metropolitan area of Kampala (Uganda) three different urban farming types were identified: subsistence farming, garden farming and commercial farming. These three urban farming types have their own spatial organisation logic and each interact in a specific way with urban expansion. In this paper the possible outcome of three alternative urban management strategies for Kampala (urban sprawl, urban infilling and a combination of both) were translated into spatially explicit land use scenarios for the years 2020 and 2030. This allowed to evaluate the spatial impact of each scenario on the future viability of the different urban farming practices. Urban sprawl fragments large open spaces thereby reducing the space for subsistence farming with 80% by 2030. Urban infilling, on the other hand, decreases the opportunities for small to medium scale garden and commercial farming by a possible reduction of 62% of the available farming land by 2030. The results of the analysis are useful for urban planners as they give insight in the potential future effects of proposed planning strategies on urban farming.
Mapping of vegetation in mountain areas based on remote sensing is obstructed by atmospheric and ... more Mapping of vegetation in mountain areas based on remote sensing is obstructed by atmospheric and topo-graphic distortions. A variety of atmospheric and topographic correction methods has been proposed to minimize atmospheric and topographic effects and should in principle lead to a better land cover classification. Only a limited number of atmospheric and topographic combinations has been tested and the effect on class accuracy and on different illumination conditions is not yet researched extensively. The purpose of this study was to evaluate the effect of coupled correction methods on land cover classification accuracy. Therefore, all combinations of three atmospheric (no atmospheric correction, dark object subtraction and correction based on transmittance functions) and five topographic corrections (no topo-graphic correction, band ratioing, cosine correction, pixel-based Minnaert and pixel-based C-correction) were applied on two acquisitions (2009 and 2010) of a Landsat image in the Romanian Carpathian mountains. The accuracies of the fifteen resulting land cover maps were evaluated statistically based on two validation sets: a random validation set and a validation subset containing pixels present in the difference area between the uncorrected classification and one of the fourteen corrected classifications. New insights into the differences in classification accuracy were obtained. First, results showed that all corrected images resulted in higher overall classification accuracies than the uncorrected images. The highest accuracy for the full validation set was achieved after combination of an atmospheric correction based on transmittance functions and a pixel-based Minnaert topographic correction. Secondly, class accuracies of especially the coniferous and mixed forest classes were enhanced after correction. There was only a minor improvement for the other land cover classes (broadleaved forest, bare soil, grass and water). This was explained by the position of different land cover types in the landscape. Finally, coupled correction methods showed most efficient on weakly illuminated slopes. After correction, accuracies in the low illumination zone (coš ≤ 0.65) were improved more than in the moderate and high illumination zones. Considering all results, best overall classification results were achieved after combination of the transmittance function correction with pixel-based Minnaert or pixel-based C-topographic correction. Furthermore, results of this bi-temporal study indicated that the topographic component had a higher influence on classification accuracy than the atmospheric component and that it is worthwhile to invest in both atmospheric and topographic corrections in a multi-temporal study.
Landscape researchers have devoted relatively little attention to ordinary or everyday landscapes... more Landscape researchers have devoted relatively little attention to ordinary or everyday landscapes. This paper investigates differences in opinion about the attractiveness of these landscapes between groups of people according to their linguistic area and other socio-demographic characteristics. A survey of 1,542 Dutch and French speakers in Belgium using photo-questionnaires depicted the different types of Belgian rural landscape. Significant differences were observed regarding landscapes containing the same features, allowing to posit, to test, and to validate certain hypotheses. Dutch speakers found chessboard agrarian landscapes more attractive. Less educated participants felt more positive towards anthropogenic landscapes. Women were more attracted by farmed fields. Qualitative data added depth to the analysis, permitting to explore different ways in which people related to the landscape pictures. For a theoretical interpretation, we draw on Gibson's affordances theory and we revisit Larrère & Larrère's ways of looking at landscape theory.
Policy has long been considered as one of the major driving forces for land use change and agricu... more Policy has long been considered as one of the major driving forces for land use change and agricultural development. However, a designated and in-depth study on its interaction with land use change and agricultural development is still very limited. The authors, therefore, attempted to address this issue by using five villages representing three agro-ecologies (highland, midland and lowland) for the period between 1965 and 2007. The study indicated that land policies of the imperial and communist regimes contributed largely to the increase of arable land while a decrease in vegetated land. This is, however, reversed in the EPRDF regime. Land productivity/crop harvest (t/ha) and herd size per household have declined. Agricultural policies played active roles in the change of water area and indirectly contributed to the change of construction land.
Uploads
Papers by Anton Van Rompaey