Pramote Prasartkul

Land use change: complexity and comparisons

Research on the determinants of land use change and its relationship to vulnerability (broadly defined), biotic diversity and ecosystem services (e.g. Gullison et al. 2007), health (e.g. Patz et al. 2004) and climate change (e.g. van der Werf et al. 2004) has accelerated. Evidence of this increased interest is demonstrated by several examples. Funding agencies in the US (National Institutes of Health, National Science Foundation, National Aeronautics and Space Administration and National Oceanic and Atmospheric Administration) and around the world have increased their support of land use science. In addition to research papers in disciplinary journals, there have been numerous edited volumes and special issues of journals recently (e.g. Gutman et al. 2004; Environment & Planning B 2005; Environment & Planning A 2006; Lambin and Geist 2006; Kok, Verburg and Veldkamp 2007). And in 2006, the Journal of Land Use Science was launched. Land use science is now at a crucial juncture in its maturation process. Much has been learned, but the array of factors influencing land use change, the diversity of sites chosen for case studies, and the variety of modeling approaches used by the various case study teams have all combined to make two of the hallmarks of science, generalization and validation, difficult within land use science. This introduction and the four papers in this themed issue grew out of two workshops which were part of a US National Institutes of Health (NIH) ‘Roadmap’ project. The general idea behind the NIH Roadmap initiative was to stimulate scientific advances by bringing together diverse disciplines to tackle a common, multi-disciplinary scientific problem. The specific idea behind our Roadmap project was to bring together seven multi-disciplinary case study teams, working in areas that could be broadly classified as inland frontiers, incorporating social, spatial and biophysical sciences, having temporal depth on both the social and biophysical sides, and having had long-term funding. Early in our Roadmap project, the crucial importance of modeling, particularly agent-based modeling, for the next phase of land-use science became apparent and additional modelers not affiliated with any of the seven case studies were brought into the project. Since agent-based simulations attempt to explicitly capture human behavior and interaction, they were of special interest. At the risk of oversimplification, it is worth briefly reviewing selected key insights in land use science in the past two decades to set the stage for the papers in this themed issue. One of the earliest realizations, and perhaps most fundamental, was accepting the crucial role that humans play in transforming the landscape, and concomitantly the distinction drawn between land cover (which can be seen remotely) and land use (which, in most circumstances, requires in situ observation; e.g. Turner, Meyer and Skole 1994). The complexity of factors influencing land use change became apparent and led to a variety of ‘box and arrow’ diagrams as conceptual frameworks, frequently put together by committees rarely agreeing with one another on all details, but agreeing among themselves that there were many components (social and biophysical) whose role needed to be measured and understood. A series of case studies emerged, recognizing the wide array of variables that needed to be incorporated, and typically doing so by assembling a multidisciplinary team (Liverman, Moran, Rindfuss and Stern 1998; Entwisle and Stern 2005). The disciplinary make-up of the team strongly influenced what was measured and how it was measured (see Rindfuss, Walsh, Turner, Fox and Mishra 2004; Overmars and Verburg 2005), with limited, if any, coordination across case studies (see Moran and Ostrom 2005 for an exception). In large part, the focus on case studies reflected the infancy of theory in land use science. Teams combined their own theoretical knowledge of social, spatial and ecological change with an inductive approach to understanding land use change – starting from a kitchen sink of variables and an in-depth knowledge of the site to generate theory on the interrelationships between variables and the importance of contextual effects. This lack of coordination in methods, documentation and theory made it very difficult to conduct meta-analyses of the driving factors of land use change across all the case studies to identify common patterns and processes (Geist and Lambin 2002; Keys and McConnell 2005). Recognizing that important causative factors were affecting the entire site of a case study (such as a new road which opens an entire area) and that experimentation was not feasible, computational, statistical and spatially explicit modeling emerged as powerful tools to understand the forces of land use change at a host of space–time scales (Veldkamp and Lambin 2001; Parker, Manson, Janssen, Hoffmann, and Deadman 2003; Verburg, Schot, Dijst and Veldkamp 2004). Increasingly, in recognition of the crucial role of humans in land use change, modeling approaches that represent those actors as agents have emerged as an important, and perhaps the dominant, modeling approach at local levels (Matthews, Gilbert, Roach, Polhil and Gotts 2007). In this introductory paper we briefly discuss some of the major themes that emerged in the workshops that brought together scientists from anthropology, botany, demography, developmental studies, ecology, economics, environmental science, geography, history, hydrology, meteorology, remote sensing, geographic information science, resource management, and sociology. A central theme was the need to measure and model behavior and interactions among actors, as well as between actors and the environment. Many early agent-based models focused on representing individuals and households (e.g. Deadman 1999), but the importance of other types of actors (e.g. governmental units at various levels, businesses, and NGOs) was a persistent theme. ‘Complexity’ was a term that peppered the conversation, and it was used with multiple meanings. But the dominant topic to emerge was comparison and generalization: with multiple case studies and agent-based models blooming, how do we compare across them and move towards generalization? We return to the generalization issue at the end of this introductory paper after a brief discussion of the other themes.

Correlates of unintended pregnancy among currently pregnant married women in Nepal.

BackgroundWomen living in every country, irrespective of its development status, have been facing the problem of unintended pregnancy. Unintended pregnancy is an important public health issue in both developing and developed countries because of its negative association with the social and health outcomes for both mothers and children. This study aims to determine the prevalence and the factors influencing unintended pregnancy among currently pregnant married women in Nepal.MethodsThis paper reports on data drawn from Nepal Demographic and Health Survey (NDHS) which is a nationally representative survey. The analysis is restricted to currently pregnant married women at the time of survey. Association between unintended pregnancy and the explanatory variables was assessed in bivariate analysis using Chi-square tests. Logistic regression was used to assess the net effect of several independent variables on unintended pregnancy.ResultsMore than two-fifth of the currently pregnant women (41%) reported that their current pregnancy was unintended. The results indicate that age of women, age at first marriage, ideal number of children, religion, exposure to radio and knowledge of family planning methods were key predictors of unintended pregnancy. Experience of unintended pregnancy augments with womens age (odds ratio, 1.11). Similarly, increase in the womens age at first marriage reduces the likelihood of unintended pregnancy (odds ratio, 0.93). Those who were exposed to the radio were less likely (odds ratio, 0.63) to have unintended pregnancy compared to those who were not. Furthermore, those women who had higher level of knowledge about family planning methods were less likely to experience unintended pregnancy (odds ratio, 0.60) compared to those having lower level of knowledge.ConclusionOne of the important factors contributing to high level of maternal and infant mortality is unintended pregnancy. Programs should aim to reduce unintended pregnancy by focusing on all these identified factors so that infant and maternal mortality and morbidity as well as the need for abortion are decreased and the overall well-being of the family is maintained and enhanced.

Continuous and Discrete: Where They Have Met in Nang Rong, Thailand

A major challenge facing the scientific community is to link people to the land so that social behavior can be studied meaningfully in relation to changes in land use and land cover types, landscape conditions, and associated ecosystem processes. One aspect of the challenge is that the linking must take place at appropriate spatial and temporal scales. Another aspect of the challenge is that social data are typically discrete, referring to point locations, whereas data on land cover and land use are typically continuous. In this paper, we examine the linking of people to the land through data transformations that move from the discrete to the continuous and from the continuous to the discrete, with particular reference to our research in Nang Rong, Thailand. We describe approaches used at the village level, which involve setting village territories, use of population distributions models, and integrating social survey data to describe land activities with satellite-based land cover classifications to describe land composition and spatial organization. These approaches are assessed relative to their underlying assumptions, their advantages and disadvantages, and their limitations. We also discuss our experience measuring links at a more micro level, between households and the plots they use. Although our discussion is with reference to a specific setting and site, many of the general points apply to other complex rural environments in which villages consist of clusters of dwelling units surrounded by agricultural lands, and in which households may farm multiple, non-contiguous parcels.

Under-registration of deaths in Thailand in 2005-2006: results of cross-matching data from two sources

OBJECTIVE To estimate the magnitude of under-registration of deaths, by age and sex, in Thailand. METHODS THE DATA IN THIS STUDY WERE DERIVED FROM TWO SOURCES: the Thai Survey of Population Changes (SPC) 2005-2006, a consecutive multi-round household survey conducted over a 12-month period, and Thailands vital registration records. SPC death entries for people of all ages were matched to 2005-2006 death records from vital registration. The principles of a dual records system were applied to estimate the magnitude of under-registration of deaths, classified by age and sex, using the Chandrasekaran-Deming formula. FINDINGS Overall under-registration of deaths during 2005-2006 was 9.00% (95% confidence interval, CI: 8.95-9.05) for males and 8.36% (95% CI: 8.31-8.41) for females. For both males and females, under-registration decreased as age increased. Under-registration was greatest among people of either sex aged 1-4 years, whereas it was < 10% among people 60 years of age and older, both males and females. CONCLUSION These findings provided correction factors that can be used for adjusting mortality data from the registration system.

Obesity and mortality among older Thais: a four year follow up study

BackgroundTo assess the association of body mass index with mortality in a population-based setting of older people in Thailand.MethodsBaseline data from the National Health Examination Survey III (NHES III) conducted in 2004 was linked to death records from vital registration for 2004-2007. Complete information regarding body mass index (BMI) (n = 15997) and mortality data were separately analysed by sex. The Cox Proportional Hazard Model was used to test the association between BMI and all-cause mortality controlling for demographic, socioeconomic, and health risk factors.ResultsDuring a mean follow-up time of 3.8 years (60545.8 person-years), a total of 1575 older persons, (936 men and 639 women) had died. A U-shaped and reverse J-shaped of association between BMI and all-cause mortality were observed in men and women, respectively. However there was no significant increased risk in the higher BMI categories. Compared to those with BMI 18.5-22.9 kg/m2, the adjusted hazard ratios (HR) of all-cause mortality for those with BMI <18.5, 23.0-24.9, 25.0-27.4, 27.5-29.9, 30.0-34.9, and ≥35.0 were 1.34 (95% CI, 1.14-1.58), 0.79 (95% CI, 0.65-0.97), 0.81 (95% CI, 0.65-1.00), 0.67 (95% CI, 0.48-0.94), 0.60 (95% CI, 0.35-1.03), and 1.87 (95% CI, 0.77-4.56), respectively, for men, and were 1.29 (95% CI,1.04-1.60), 0.70 (95% CI, 0.55-0.90), 0.79 (95% CI, 0.62-1.01), 0.57 (95% CI, 0.41-0.81), 0.58 (95% CI, 0.39-0.87), and 0.78 (95% CI, 0.38-1.59), respectively, for women.ConclusionsThe results of this study support the obesity paradox phenomenon in older Thai people, especially in women. Improvement in quality of mortality data and further investigation to confirm such association are needed in this population.

Measuring housing quality in the absence of a monetized real estate market

Measuring housing quality or value or both has been a weak component of demographic and development research in less developed countries that lack an active real estate (housing) market. We describe a new method based on a standardized subjective rating process. It is designed to be used in settings that do not have an active, monetized housing market. The method is applied in an ongoing longitudinal study in north-east Thailand and could be straightforwardly used in many other settings. We develop a conceptual model of the process whereby households come to reside in high-quality or low-quality housing units. We use this theoretical model in conjunction with longitudinal data to show that the new method of measuring housing quality behaves as theoretically expected, thus providing evidence of face validity.

Changes in Active Life Expectancy Among Older Thais: Results From the 1997 and 2004 National Health Examination Surveys

This study aims to determine the disability prevalence and changes in active life expectancy of the Thai older people between 1997 and 2004. Data on disability of older people aged ≥60 years were obtained from the National Health Examination Surveys. Disability refers to one or more restrictions on the activities of daily living. The Sullivan method was used to calculate active life expectancy. A total of 4048 older people in 1997 and 19 372 older people in 2004 were included in the analysis. Active life expectancy at age 60 of men was 16.5 years in 1997 and 17.6 years in 2004, whereas that of women was 17.9 and 19.9 years, respectively. Women spent a greater proportion of the remaining life with disability. The proportion of active life for both genders also increased during the 7-year period suggesting an evidence of the compression of morbidity in Thai older people.

Household-Parcel Linkages in Nang Rong, Thailand

An understanding of the dynamic connections between human behavior and the biophysical environment requires that people and land be spatially linked, conceptually and operationally. This paper describes the design and execution of a plan for spatially linking at a fine grain level: households and land parcels in Nang Rong, Thailand. The overall goal was to relate household dynamics to land use. There were several challenges that had to be surmounted: the large number of links to be determined given the sample size; a residential pattern with clustered dwelling units located away from the land farmed); a complex pattern of ownership and use; and the absence of a clear one-to-one relationship between households and parcels (a household using several plots; several households using the same plot). The paper reviews decisions about the design of the data collection, including the decision to start with households and then link to plots, to focus on use rather than ownership, to rely on a village headman informant to collect GPS data on the location of dwelling units, to collect information from households about each plot used and its proximate neighbors, to collect locational information about the plots used by each household from a group interview, and to manually match the last two. The paper describes in detail the options available at each point in the design process, and the reasons for choosing as we did; the map products that were prepared, their cost, and mode of use; the interviewing that took place; problems that arose; and the quality of the links, as far as we are able to evaluate at this point.

New developments in the analysis of mortality and causes of death.

This book on new developments in mortality analysis is a product of a joint WHO/UN research program. Part 1 examines mortality transition in terms of the causes and mechanisms of mortality decline in Europe and North America reflecting on the study of development processes in countries now undergoing development. Part 2 deals with the use of mortality data in health planning and the use of mortality and other epidemiologic information in the assessment of preventable deaths. Attention is paid to the development of an index of preventable deaths. Part 3 Methodological Developments examines intersectoral aspects of mortality projections (in terms of health care inputs) the measurement of social inequality and mortality and maternal death and its impact on the female population. Part 4 deals with cause of death analysis: estimation of global mortality patterns by cause of death trends and differentials in Thailand and maternal mortality and differentiation by cause of death. Part 5 discusses nutrition including a Southern Asia-based study of the relationship between nutritional deficiencies and infant and child mortality and a study on advances in child nutrition and health that have taken place despite slow economic development. Part 6 discusses mortality change: achievements and failures in South and East Asia a study on changing health in Japan mortality decline in Mexico and socioeconomic correlates of mortality in Pakistan. The section concludes with articles on trends and differentials in mortality in Malaysia and Thailand and a study of the effects of declining mortality and population aging in rapidly-developing Jamaica.

A workplace intervention program and the increase in HIV knowledge, perceived accessibility and use of condoms among young factory workers in Thailand

Abstract Vulnerability to Human Immunodeficiency Virus (HIV) infection among factory workers is a global problem. This study investigated the effectiveness of an intervention to increase AIDS knowledge, perceived accessibility to condoms and condom use among young factory workers in Thailand. The intervention was a workplace program designed to engage the private sector in HIV prevention. A cross-sectional survey conducted in 2008 to measure program outcomes in factories in Thailand was used in this study. The workplace intervention included the development of policies for management of HIV-positive employees, training sessions for managers and workers, and distribution of educational materials and condoms. A multi-level analysis was used to investigate the effect of HIV/AIDS prevention program components at the workplace on HIV/AIDS knowledge, perceived accessibility to condoms and condom use with regular sexual partners among 699 young factory workers (aged 18–24 years), controlling for their individual socio-demographic characteristics. Interventions related to the management and services component including workplace AIDS policy formulation, condom services programs and behavioral change campaigns were found to be significantly related to increased AIDS knowledge, perceived accessibility to condoms and condom use with regular partners. The effect of the HIV/AIDS training for managers, peer leaders and workers was positive but not statistically significant. With some revision of program components, scaling up of workplace interventions and the engagement of the private sector in HIV prevention should be seriously considered.