This thesis consists of three self-contained chapters on issues related to spillover effects of behavioral and policy interventions aimed at reducing negative incentives provided by consumption and production subsidies, and discusses the implications for environmental policy design. The first two chapters investigate spillover effects of a behavioral intervention aimed at incentivizing residential water savings in Colombia.

We use rich survey data to investigate the economic impact of a climate-friendly rice farming method known as the system of rice intensification (SRI) on the welfare of rain-dependent smallholder farmers in Africa. SRI reduces water consumption by half, which makes it a promising farming system in the adaptation to climate change in moisture-constrained areas, and it does not require flooding of rice fields, resulting in reduced methane emissions.

Maize is a strategic commodity for improving food security and alleviating poverty in Tanzania, but its productivity remains low. The importance of improved maize varieties (IMVs) in increasing productivity is documented in existing literature. Previous adoption studies in Tanzania did not examine the factors that influence the speed/timing of adoption. This study examines the determinants of the speed of adoption of IMVs using a duration model and recently collected plot- and household-level data in rural Tanzania.