Intervention (Hidden)
We will implement a randomized field experiment to test if farmers have higher acceptance of specific circular economy practices, namely conversion of biowaste from tomato production into biochar, when the conversion is framed as an individual vs. collective issue.
We will implement a public goods game combined with two video treatments about circular economy solutions. The 1st treatment presents circular economy (biochar) as collectively beneficial. The 2nd treatment presents circular economy (biochar) as individually beneficial.
The control group watches a video that provides information about what biochar is, without framing or mentioning benefits. The video for the control group has the following content:
Biochar is a type of processed plant matter that is very rich in carbon. Lightweight, black and porous, it looks and feels very much like charcoal. But where charcoal is used for cooking and heat, biochar is used in soils to help grow crops. Biochar efficiently stores carbon from plant material instead of releasing it into the atmosphere. This makes it far cleaner than other forms of charcoal. It can be produced using any organic material from agriculture or forestry wastes such as wood chips or dead plants. Organic waste after tomato harvests such as leaves, stems and branches can also be used to produce biochar. Biochar is produced by burning these materials in an oxygen-deprived fire, in a process called pyrolysis. Production technologies range from commercial biochar production kilns to small-scale kilns operated on farms including drum kilns, retort kilns, brick kilns and and others. Biochar is often mixed with compost or other materials to improve soil properties by introducing beneficial nutrients. Biochar can also reduce soil degradation and groundwater pollution, which lowers costs, and increases food security and profitability for farmers.
Circular economy video treatments
1. Individual message treatment
The video starts with a broad biochar definition as in the control group and in addition contains the following facts about tomato production, biowaste and biochar:
An average farm produces around 3 tons of tomatoes per acre.
This leaves behind 1 ton of waste from stems, branches and leaves.
This waste can be converted to 400 kg of biochar.
The estimated value of this amount of biochar from tomato plant residue is 20,000 KSh.
This amount of biochar can be used to improve soil properties on 0.3 acres of land.
Key message
By repurposing on-farm waste, you can turn your farm into a green growth engine.
You reduce environmental damage.
You slow down global warming.
You produce more healthy foods.
You create more economic value.
2. Collective message treatment
The video starts with a broad biochar definition as in the control group and in addition contains the following facts about tomato production, biowaste and biochar:
Total tomato production in Kenya is 545,000 tons.
This leaves behind 180,000 tons of waste from stems, branches and leaves.
This waste can be converted to 72,000 tons of biochar.
The estimated value of this amount of biochar from tomato plant residue is 3.6 billion KSh.
This amount of biochar can be used to improve soil properties on 25,000 hectares of land.
Key message
By repurposing on-farm waste, we can turn our farms into green growth engines.
We reduce environmental damage.
We slow down global warming.
We produce more healthy foods.
We create more economic value.