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Valentin Guye

@valentinguye.bsky.social
173 followers 230 following 19 posts

I do research on sustainable use & trade of land resources. INRAE researcher at the Center for Environmental Economics of Montpellier, France. Also in trase.earth More at valentinguye.github.io

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Reposted by Valentin Guye
Trase @trase.earth · 24/03/2026
🚨New Trase factsheets for all 27 EU member states now available 🚨 Trase has published its latest assessment of the EU's links to global deforestation through its imports of over 150 agricultural commodities. Read the Insight on EU Deforestation Exposure here -> trase.earth/insights/eu-...
Graph showing the EU27 is most exposed to deforestation via imports of cocoa from Cote d'Ivoire, Brazilian soy and beef, and Indonesian palm oil
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Valentin Guye @valentinguye.bsky.social · 21/01/2026
P.s. In the paper, we further unpack how price signals influence deforestation and provide original statistics on palm oil mills. Check it out and do not hesitate to get in touch!
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Valentin Guye @valentinguye.bsky.social · 21/01/2026
We are thankful to everyone who advised us on this research, and especially to the reviewers and editors at AJAE for their thoughtful engagement with our work.
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Valentin Guye @valentinguye.bsky.social · 21/01/2026
This warns that market forces may eclipse existing conservation policies. But they also mean that a uniform refundable tax can curb unregulated deforestation—we estimate CO₂-related revenue in the hundreds of millions of dollars—and that compensating smallholders would further boost effectiveness.
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Valentin Guye @valentinguye.bsky.social · 21/01/2026
For smallholders, however, the positive elasticity is driven by the influence of the mills they depend on. Controlling for mills’ influence, smallholders actually deforest less as they receive higher prices.
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Valentin Guye @valentinguye.bsky.social · 21/01/2026
We find that deforestation responds to crude palm oil price signals upstream in the Indonesian supply chain—notably, deforestation for smallholder and for illegal industrial plantations.
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Valentin Guye @valentinguye.bsky.social · 21/01/2026
To identify the causal price elasticity of deforestation, we construct the first map of mill-gate prices and exploit its granularity. This lets us isolate exogenous price shifts stemming from mills’ idiosyncratic deal schedules and pricing rules imposed by their buyers.
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Valentin Guye @valentinguye.bsky.social · 21/01/2026
To answer this, we draw on manufacturing census data on palm oil mills and remote-sensing data over Sumatra and Kalimantan—the main palm oil regions—from 1998 to 2014.
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Valentin Guye @valentinguye.bsky.social · 21/01/2026
But do price signals actually reach the upstream end of the supply chain and incentivize these unregulated plantations?
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Valentin Guye @valentinguye.bsky.social · 21/01/2026
🔔 New study: palm oil prices & unregulated deforestation 🔔 doi.org/10.1002/ajae... 🪚🔥🌴 Tropical forest loss for oil palm has slowed in Indonesia. Yet, because conservation schemes barely address smallholder and illegal industrial expansion, rising market forces may revive deforestation.
doi.org
Price incentives and unregulated deforestation: Evidence from Indonesian palm oil mills
Global demand shifts and supply chain interventions have the potential to reduce palm oil's environmental footprint, especially in otherwise unregulated plantations. This ultimately depends on defore...
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Valentin Guye @valentinguye.bsky.social · 03/09/2025
In addition to all who helped me with this work, I am thankful to the 2 reviewers and the editor at Environmental and Resource Economics, journal of @eaere.bsky.social
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Valentin Guye @valentinguye.bsky.social · 03/09/2025
Do not hesitate to reach out, especially if you need the accepted version of the manuscript.
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Valentin Guye @valentinguye.bsky.social · 03/09/2025
To apply these tests, I detect crop-specific expansion responses across the tropics to pre-determined – therefore exogenous – increments in maize demand in the US.
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Valentin Guye @valentinguye.bsky.social · 03/09/2025
I first map the theoretical ILUC mechanisms to a variety of crops. 🌾 Within this framework, observing specific crops provides empirical tests of specific mechanisms.
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Valentin Guye @valentinguye.bsky.social · 03/09/2025
– Reduced-form paper on indirect land use change and biofuels –  Biofuels can cut fossil use—but if feedstock demand drives tropical deforestation, climate gains vanish.  In this new paper, I test the theoretical mechanisms behind this. 🔗 link.springer.com/article/10.1...
link.springer.com
Indirect Land use Change Mechanisms: Tests from Biofuel Mandates and Pantropical Agriculture - Environmental and Resource Economics
Agricultural supply and demand shocks can indirectly cause environmental damages as they propagate across space, time and commodity markets according to mechanisms that have been extensively theorized...
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Reposted by Valentin Guye
Bon Pote @bonpote.com · 26/06/2025
Depuis quelques jours, la Méditerranée est en surchauffe, avec une canicule marine et des écarts de +5°C. L'équivalent d'incendies sous-marin, avec une faune qui "faune et flore qui meurent comme si elles étaient brûlées" : bonpote.com/canicules-ma...
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Valentin Guye @valentinguye.bsky.social · 08/11/2024
Using Trase's supply chain model for Côte d'Ivoire cocoa, I found that #traceability differs across departments of origin, trading companies and countries of destination, and I reflected on the implications at each level regarding the EU deforestation regulation. bit.ly/4cy8zKN
bit.ly
Smallholder cocoa farmers need support as EUDR compliance nears - Insights - Trase
Trase research shows huge variations in the traceability of cocoa from Côte d’Ivoire and the likelihood of whether supplies will comply with the EU deforestation regulation. Support for smallholder fa...
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Valentin Guye @valentinguye.bsky.social · 13/05/2024
Last week, Trase released modelled data on the subnational Ivorian cocoa supply chain and embedded deforestation, from department to importing country, by trader, annually (2019-22). All useful links here: trase.earth/insights/cot... + to new open data on cooperatives: doi.org/10.14428/DVN...
trase.earth
Côte d'Ivoire cocoa exports and deforestation - Insights - Trase
Trase maps the international trade in cocoa from Côte d’Ivoire revealing which trading companies and consumer markets are most exposed to deforestation.
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Valentin Guye @valentinguye.bsky.social · 13/12/2023
Furthermore, the disclosed supply chains are concentrated in space, leaving vast areas where virtually all companies deny to hold themselves accountable, including in districts with lots of cocoa adjacent to remaining forest.
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Valentin Guye @valentinguye.bsky.social · 13/12/2023
The companies disclosing their supply chains as part of their efforts to build accountability for sustainable sourcing handle 80% of cocoa exports from Ghana. Yet, the content of these disclosures allow to recover the district of production for only 9% of exports.
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Valentin Guye @valentinguye.bsky.social · 13/12/2023
🍫As part of the research we - the Land Systems for Sustainability Lab - do in the Trase partnership, I collect supply chain disclosures made by cocoa traders. In Ghana, we find that these disclosures are of poor quality, raising doubts about sustainable sourcing claims.
insights.trase.earth
Cocoa traders fall short on supplier disclosure in Ghana
Companies exporting cocoa from Ghana are failing to publicly demonstrate that their supplies are not grown on deforested land, according to research by Trase, raising questions over their sustainabili...
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