Robin Hide

The sustainability of Papua New Guinea agricultural systems: the conceptual background

Abstract Papua New Guinea offers an opportunity to study the Intensification and sustainability of village agriculture under the pressures of demographic change and social and economic development. This paper describes research investigating the process of agricultural intensification. Theories of intensification suggest the process is associated with increasing population, or with increased production for social purposes, or both. Intensification brings about changes that must be overcome by innovation. Innovation may demand temporary or permanent increases in labour, and changes in the social relations of production, but intensification without innovation is likely to lead to land degradation. A tension exists between the environment, social organization, production and the adoption of innovative techniques, which may determine whether intensification is sustainable. The research is presently identifying, mapping and systematically describing agricultural systems. Preliminary results suggest intensification is positively associated with altitude, sweet potato (lpomoea batatas) cultivation, and with a number of innovative agronomic techniques.

Regional patterns of birthweights in Papua New Guinea in relation to diet, environment and socio-economic factors

Regional differences in mean birthweight in rural Papua New Guinea (PNG) and the importance of differences in family diet and maternal education and socio-economic status on such patterns were explored using birthweight data collected by the 1982/83 PNG National Nutrition Survey. A total of 6137 birthweight measurements from 85 PNG districts were available, representing 22% of all children included in the survey. The nature of possible selection biases are assessed and their implications discussed. Hierarchical Bayesian spatial models based on conditional autoregressive (CAR) priors were used to model spatial patterns in birthweights and their relation to different sets of covariates. Birthweights were found to exhibit striking geographical differences. Children from the central PNG highlands and from affluent lowland areas had the highest birthweights, while they were lowest in the (largely lowland) Sepik, Western, Madang and Milne Bay Provinces and in remote highland fringe areas. Maternal education, socio-economic status and diet were all important predictors, but only differences in family diet were correlated with the observed spatial patterns. The results of the present study highlight the importance of nutrition and socio-economic status in explaining differences in birthweights in PNG. Besides improving maternal health, interventions for improving birthweights in PNG should therefore aim at strengthening the economic base of rural populations and promote the cultivation and consumption of high quality foods.