Livelihood and Dietary Transitions in Subsistence Populations of Northern Laos: Insights From Carbon and Nitrogen Stable Isotope Analysis
Ziyang Li, Mihoko Kibe, Yuki Mizuno, Masafumi Saitoh, Kohei Yamazaki, Hiroaki Masuoka, Satoko Kosaka, Kazumi Natsuhara, Kazuhiro Hirayama, Nouhak Inthavong, Sengchanh Kounnavong, Minoru Yoneda, Shinsuke Tomita, Masahiro UmezakiABSTRACT
Objectives
Rural populations in northern Laos have experienced dramatic socioeconomic transformation driven by national policies and regional economic integration, substantially influencing their self‐sufficient livelihoods. To investigate how these changes have manifested in local subsistence contexts, we compared hair carbon and nitrogen isotope values between two populations representing swidden‐ and paddy‐farming systems, and assessed how isotopic variations reflect the differences in subsistence practices and degrees of livelihood transformation. By analyzing commonly consumed foodstuffs, we provide the first isotopic dataset of foods from northern Laos and baselines for interpreting human tissue isotope values.
Methods
Scalp hair and food samples and sociodemographic data were collected from the study villages. In total, 175 hair and 69 food samples were analyzed. Multiple linear regression analyses were used to examine associations with subsistence/economic and dietary variables. Rice–hair isotopic offsets were calculated to qualitatively assess dietary patterns.
Results
Hair δ 15 N was higher in the paddy‐farming village than in the swidden‐farming village. In the swidden‐farming village, individuals who shifted to paddy cultivation showed higher δ 15 N and lower δ 13 C values than those who primarily practiced swidden cultivation. In the paddy‐farming village, individuals with greater market involvement exhibited higher hair δ 13 C values. The rice–hair offsets suggested elevated market food consumption among paddy field cultivators.
Discussion
The differences in hair isotope values between (sub)populations can be attributed to isotopic variations in rice, the staple food, and to the differences in market participation. Market integration can lead to an increase in hair δ 13 C, but the overall isotopic outcome is highly context dependent.