Research

Working Papers

Fenced In: Biodiversity Loss, Land Degradation, and Livestock Production in Southern Africa (Job Market Paper)

Biodiversity provides essential ecosystem services to human welfare, yet the topic is understudied in economic literature. This paper estimates the cost of herbivore biodiversity declines in Southern Africa via the mechanism of bush encroachment, a form of land degradation in which trees and shrubs expand into grasslands used to range cattle. Since wild herbivores control encroachment, biodiversity loss potentially decreases cattle production by reducing available rangeland. We exploit the placement of livestock fencing across Namibia and Botswana as a natural experiment in local biodiversity changes. Using these fences to instrument for encroachment induced by biodiversity loss, we estimate causal impacts on cattle density across the region and find that a one square kilometer increase in shrub cover decreases cattle density by around 13 individuals. These estimates suggest there were around 2.5 million fewer cattle in 2020 compared to 2002, equal to more than 60 million USD in lost trade revenue in 2020 alone. Finally, we use a machine learning algorithm to predict species distributions based on observational data and combine this with expert range maps to examine the role of biodiversity as a driving mechanism.

Urban Tree Loss and Unequal Adaptation to the Emerald Ash Borer (Draft available upon request)

In this paper, I leverage the semi-exogenous shock of the Emerald Ash Borer (EAB), an invasive ash tree killing beetle, to examine whether social inequality increased or decreased the severity of beetle’s impact on urban forests in the city of Chicago. I start by examining the effect of the beetle on ash tree removal and overall tree cover using both difference-in-difference and event study specifications. I find that despite having more trees susceptible to infection, neighborhoods with more ash trees do not have more ash trees removed following the initial appearance of EAB. Using a network SIR model to simulate the natural spread of the beetle, this paper reveals discrepancies between expected and realized tree removals and potentially indicates shadow adaptation—if fewer ash trees are removed than expected, this could suggest that areas were able to adequately protect their trees against the EAB shock. I find that such areas with plausibly higher adaptation tend to be areas with more white households, higher incomes, and higher educational attainment, suggesting that EAB seems to have been less harmful to more privileged areas with the resources to adapt. Overall, this paper underscores the importance of adaptive behavior in the impact of exogenous ecological shocks, arguing for increased use of ecological models to properly understand counterfactuals in econometric analysis.

Other Works in Progress

Substitutability between Biodiversity and Climate Change (with Seung Min Kim)

Physical and Mental Health Benefits from Urban Parks (with Abigail Dow and Graeme Peterson)