Epsilon Archive for Student Projects

Abstract

Tea (Camellia sinensis) cultivation has long been a major livelihood in Thai Nguyen, Vietnam. The region’s growing interest in certified organic production offers new opportunities for farmers, yet limited data exist on its environmental and physiological impacts, particularly regarding heavy metal accumulation. This study aimed to compare the social dimensions and crop management of
organic and conventional tea systems and assess their implications for soil quality and tea safety. A mixed methods approach combined farmer interviews with analyses of soil and leaf chemical properties.

Farmers generally viewed organic practices positively, citing benefits for health and the environment, although many later emphasized that integrating mineral fertilizers with organic ones resulted in better yields and higher quality. Chemically, all farm plots exhibited severe soil
acidification and Zn levels exceeding the Vietnamese permissible limits. Organic systems, however, tended to have soils with lower Zn and Cu concentrations and higher organic carbon content than the conventional farms. Tea metabolites on the therhand (caffeine, catechins,and polyphenols) did not differ significantly between systems and the estimated heavy metal intakes from all teas indicated no potential health risk to consumers. Heavy metal stress affected tea
quality, with Cu accumulation in leaves reducing caffeine content. Overall, organic farming demonstrated potential to improve soil quality and reduce heavy metal risk to the environment, though its effectiveness remains highly dependent on local soil conditions.