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Linus Blomqvist @linusblomqvist.com · Apr 28

Looks like specific practices, rather than the organic/conventional dichotomy, determine outcomes for soil health (measured in terms of soil biota).

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Linus Blomqvist @linusblomqvist.com · Apr 28

New paper on the impacts of management and organic/conventional ag on soils: www.science.org/doi/full/10....

www.science.org

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Linus Blomqvist @linusblomqvist.com · Apr 22

Yield improvements reduced global crop water footprint
www.researchsquare.com/article/rs-6...

Yield improvements reduced global crop water footprint (1972–2018), but further action needed for water sustainability

Temporal variation in the water footprint (WF) of crop production has been less studied compared to spatial variation. This study assessed global spatiotemporal trends in the WF of crop production fro...

www.researchsquare.com

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Linus Blomqvist @linusblomqvist.com · Apr 22

... which is that if you forego a harvested crop to grow green manure, you're lowering average yields in a way that increases the land footprint of farming. To offset this, you would have to grow crops elsewhere, and that might lead to N emissions.

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Linus Blomqvist @linusblomqvist.com · Apr 22

New paper finds that adding legume and non-legume green manure improved nitrogen uptake and use efficiency in a cropping system: www.sciencedirect.com/science/arti...

There is one caveat, however... 1/n

The fate of nitrogen derived from green manure and its influence on crop N agronomic performance

Substituting synthetic nitrogen (N) with green manure (GM) is a sustainable agricultural practice. However, the role of GM nitrogen (GMN) in crop prod…

www.sciencedirect.com

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Linus Blomqvist @linusblomqvist.com · Apr 22

I myself am using GYGA (paired with FAO data) to try to understand if recent signs of yield stagnation in cropping systems around the world are due to yields hitting a ceiling, or to inadequate management. Stay tuned!

Linus Blomqvist @linusblomqvist.com · Apr 22

GYGA now covers a substantial share of crop production for important staple crops like wheat, rice, soy, and corn.

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Linus Blomqvist @linusblomqvist.com · Apr 22

This problem is getting smaller and smaller, however, as the Global Yield Gap Atlas (www.yieldgap.org) adds to its database of potential yields and yield gaps.

www.yieldgap.org

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Linus Blomqvist @linusblomqvist.com · Apr 22

Why don't we just use bottom-up methods? The reason is that their main strength--validation with local data--is also their main weakness: it is hard to scale up.

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Linus Blomqvist @linusblomqvist.com · Apr 22

Earlier papers, such as this one by van Ittersum et al (www.sciencedirect.com/science/arti...), have also shown that results from top-down models can substantially over- or under-estimate potential yields at local to regional levels.

Yield gap analysis with local to global relevance—A review

Yields of crops must increase substantially over the coming decades to keep pace with global food demand driven by population and income growth. Ultim…

www.sciencedirect.com

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Linus Blomqvist @linusblomqvist.com · Apr 22

This latest study, titled "Statistical approaches are inadequate for accurate estimation of yield potential and gaps at regional level," shows that top-down methods are unreliable assessed against better-validated bottom-up methods.

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Linus Blomqvist @linusblomqvist.com · Apr 22

If, on the other hand, these top-down methods can't distinguish between rainfed and irrigated cropping systems, they might, wrongly, infer that rainfed systems could reach the yields of irrigated systems. This leads to an overestimation of potential yields.

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Linus Blomqvist @linusblomqvist.com · Apr 22

There are many problems with top-down methods, however. For example, even the best farmers in a region can be well below the real yield potential given soils, climate, and the best available agricultural technology. This would lead to underestimating potential yields.

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Linus Blomqvist @linusblomqvist.com · Apr 22

The advantage of top-down methods is that they are easy to scale: in the simplest case, with some climate data and yield statistics from FAO, you can create a map of potential yields across the world.

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Linus Blomqvist @linusblomqvist.com · Apr 22

Top-down methods typically take potential yields to be some percentile of current, actual yields within each climate zone. Bottom-up methods use field data combined with crop growth models and weather data to estimate potential yields.

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Linus Blomqvist @linusblomqvist.com · Apr 22

Knowing the potential yields of crops is important, because it tells us something about how far we can get in meeting food demand without technological breakthroughs. There are two ways of estimating potential yields: top-down and bottom-up.

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Linus Blomqvist @linusblomqvist.com · Apr 22

I can't read this full paper because my university, quite rightly, is not willing to pay the extortionate fees charged by Nature Publishing Group, but the takeaways are clear from the abstract. 1/n

www.nature.com/articles/s43...

Statistical approaches are inadequate for accurate estimation of yield potential and gaps at regional level - Nature Food

Yield potential estimates from statistical models and process-based crop models are compared across diverse climates and soil conditions. The findings reveal limitations of statistical methods, unders...

www.nature.com

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Linus Blomqvist @linusblomqvist.com · Apr 8

Total production goes down, but the marginal land yields so little in relation to inputs that it doesn't generate a net profit. Also shows the advantage of precision ag technologies that can pinpoint yields with very high spatial resolution.

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Linus Blomqvist @linusblomqvist.com · Apr 8

I'm generally skeptical of win-wins for agriculture and biodiversity, but this one seems legit: planting perennial crops on marginal land leads to more birds without reduced profit.

Increased avian bioacoustic diversity without lost profit after planting perennial vegetation in marginal cropland

Expansion of arable cropland and intensification of agriculture has driven substantial losses of habitat, biodiversity, and ecosystem services. Balanc…

www.sciencedirect.com

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Linus Blomqvist @linusblomqvist.com · Apr 1

Here's the Cafaro paper: overpopulation-project.com/wp-content/u...

overpopulation-project.com

Linus Blomqvist @linusblomqvist.com · Apr 1

My take here (with @jennbernstein.bsky.social): linusblomqvist.substack.com/p/beyond-the...

Beyond the Population-Consumption Dichotomy

The following two statements are simultaneously true: a large human population is detrimental to non-human life, and the concept of overpopulation is both scientifically and ethically problematic.

linusblomqvist.substack.com

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Linus Blomqvist @linusblomqvist.com · Apr 1

It's 2025 and there are still people out there trying to define a maximum sustainable human population - in this case 2 billion people.

Cafaro (2025) "A New Definition of Global Overpopulation, Explained and Applied"

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Linus Blomqvist @linusblomqvist.com · Jan 14

"mitigating both plastic pollution and carbon emissions from the plastic sector could lead to a 22% increase in cropland expansion, a 35% increase in the area of cropland undergoing intensification and a 20% increase in deforestation relative to the baseline scenario." www.nature.com/articles/s41...

The potential land-use impacts of bio-based plastics and plastic alternatives - Nature Sustainability

Bio-based plastics have gained attention as a potentially sustainable way to reduce fossil fuel-based plastic demand and store carbon. However, large-scale adoption of bio-based alternatives could hav...

www.nature.com

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Linus Blomqvist @linusblomqvist.com · Dec 17

It's true, it was just never a big share. I'm not sure I'll publish the paper - issues like small sample size that could prevent publication in a good journal. So its findings should be taken as suggestive. There is anecdotal evidence (quotes, newspaper articles) that substitutes played a big role.

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Linus Blomqvist @linusblomqvist.com · Dec 17

Worth noting that the countries that didn't have state-run or heavily state-subsidized whaling all basically stopped whaling long before any international regulations came into place.

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