In this paper, with a focus on Japan and Thailand, we outline a relational environmental and economic history of East Asian economic integration (EAEI) and its implication for the commons in both places. We draw attention in particular to global commodity chains as relational processes not only of trade and investment, but also geopolitics and aid, to argue that these transborder processes have connected together commons in distant localities resulting in their simultaneous enclosure, dispossession and (re-)commoning with implications for community vulnerabilities in positive and negative ways. To demonstrate this argument we analyse three periods of EAEI: the late nineteenth century until World War II, when Japan and Thailand both began to modernise and new trade and geopolitical relations emerged in the context of colonialism; the post-World War II recovery until the Plaza Accord in 1986, during which time Japan rapidly industrialised, as did Thailand to a lesser extent and regionalism was largely defined by US hegemony; and the post-Plaza Accord period, when Japan deindustrialised its labour intensive manufacture and heavy industry and Thailand rapidly industrialised and EAEI became defined by new and intensified global commodity chains.

The present study conducted a field survey of water quality along the Chao Phraya River during the past three years. The main objective was to better understand the spatial–temporal variations in water quality in relation to season and channel morphology. It assessed the water quality in terms of chemical parameters, bacteria, and phytoplankton. The results revealed a duality of seasonal effect for nutrients. The rainy season degraded the water quality by increasing the nutrient concentration in the waterway in the beginning, but cleaned it up by dilution in the end. However, this duality did not apply to Escherichia coli (E. coli), for which the highest level occurred during the second half of the rainy season and a sag curve variation pattern was displayed along the mainstream. Another duality found by this study is that there was no statistically significant difference in water quality in terms of chemical parameters between a river bend and the straight channel shortcutting the bend, but significant differences in the level of E. coli and the phytoplankton community structure were observed between the two. Of particular note, the present study revealed a coexistence of a saproxenous species (algae found in clean water) with a harmful species in the bend river reach.