John Stepp conducts conservation research on the persistence, change and variation of traditional ecological knowledge (wild food plants and medicinal plants). He also explores patterns and causes of biocultural diversity.
Industry Expertise (2)
Floriculture and Horticulture
Areas of Expertise (6)
Indigenous Peoples Issues
Latin American Studies
Impact of mental models on constructed wetland maintenance in semi-arid IndiaWater Practice and Technology
Constructed wetlands (CWs) are a low-cost technology relying on natural processes to treat wastewater and provide a decentralized wastewater treatment option in communities with limited infrastructure. Little is known about their long-term maintenance or monitoring, or the experience of communities who adopt and maintain CWs. This research uses mental models to compare the perspectives of scientists and community members regarding CW maintenance. Forty-three semi-structured interviews with farmers, maintainers, local politicians, CW neighbors, extension agents, and scientists in four villages in south India were conducted.
Reshaping the future of ethnobiology research after the COVID-19 pandemicNature Plants
The public health crisis triggered by SARS-CoV-2, the cause of the COVID-19 disease, is teaching us that the world is no longer operating under the assumption of ‘business as usual’. According to the online global tracker managed by Johns Hopkins University1, as of the end of May 2020, there are more than 5.8 million confirmed cases of COVID-19 across 188 countries and regions, a number that is still increasing.
Changes in Tea Plant Secondary Metabolite Profiles as a Function of Leafhopper Density and DamageFrontiers in Plant Science
Insect herbivores have dramatic effects on the chemical composition of plants. Many of these induced metabolites contribute to the quality (e.g., flavor, human health benefits) of specialty crops such as the tea plant (Camellia sinensis). Induced chemical changes are often studied by comparing plants damaged and undamaged by herbivores. However, when herbivory is quantitative, the relationship between herbivore pressure and induction can be linearly or non-linearly density dependent or density independent, and induction may only occur after some threshold of herbivory. The shape of this relationship can vary among metabolites within plants.
Plant-Climate Interaction Effects: Changes in the Relative Distribution and Concentration of the Volatile Tea Leaf Metabolome in 2014–2016Frontiers in Plant Science
Climatic conditions affect the chemical composition of edible crops, which can impact flavor, nutrition and overall consumer preferences. To understand these effects, we sampled tea (Camellia sinensis (L.) Kuntze) grown in different environmental conditions. Using a target/nontarget data analysis approach, we detected 564 metabolites from tea grown at two elevations in spring and summer over 3 years in two major tea-producing areas of China. Principal component analysis and partial least squares-discriminant analysis show seasonal, elevational, and yearly differences in tea from Yunnan and Fujian provinces.
Environmental Factors Variably Impact Tea Secondary Metabolites in the Context of Climate ChangeFrontiers in Plant Science
Climate change is impacting food and beverage crops around the world with implications for environmental and human well-being. While numerous studies have examined climate change effects on crop yields, relatively few studies have examined effects on crop quality (concentrations of nutrients, minerals, and secondary metabolites). This review article employs a culturally relevant beverage crop, tea (Camelia sinensis), as a lens to examine environmental effects linked to climate change on the directionality of crop quality.