A Natural History of the Future

Why are biodiversity—ecosystem functioning relationships so elusive? Trophic interactions may amplify ecosystem function variability 

Wu et al., 2022.

1. The relationship between biodiversity and ecosystem functions (BEFs) has attracted great interest. Studies on BEF have so far focused on the average trend of ecosystem function as species diversity increases. A tantalizing but rarely addressed question is why large variations in ecosystem functions are often observed across systems with similar species diversity, likely obscuring observed BEFs.
2. Here we use a multi-trophic food web model in combination with empirical data to examine the relationships between species richness and the variation in ecosystem functions (VEFs) including biomass, metabolism, decomposition, and primary and secondary production. We then probe the mechanisms underlying these relationships, focusing on the role of trophic interactions.
3. While our results reinforce the previously documented positive BEF relationships, we found that ecosystem functions exhibit significant variation within each level of species richness and the magnitude of this variation displays a hump-shaped relationship with species richness. Our analyses demonstrate that VEFs is reduced when consumer diversity increases through elevated nonlinearity in trophic interactions, and/or when the diversity of basal species such as producers and decomposers decreases. This explanation is supported by a 34-year empirical food web time series from the Gulf of Riga ecosystem.
4. Our work suggests that biodiversity loss may not only result in ecosystem function decline, but also reduce the predictability of functions by generating greater function variability among ecosystems. It thus helps to reconcile the debate on the generality of positive BEF relationships and to disentangle the drivers of ecosystem stability. The role of trophic interactions and the variation in their strengths mediated by functional responses in shaping ecosystem function variation warrants further investigations and better incorporation into biodiversity—ecosystem functioning research.

https://bit.ly/3BQ6WJq

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Living systems are cognitive systems, and living as a process is a process of cognition. This statement is valid for all organisms, with or without a nervous system.

Humberto Maturana and Francisco Varela

(Santiago theory of cognition)

 

“I don’t like either the word or the thing. People ought to saunter in the mountains - not hike! Do you know the origin of that word ‘saunter?’ It’s a beautiful word. Away back in the Middle Ages people used to go on pilgrimages to the Holy Land, and when people in the villages through which they passed asked where they were going, they would reply, ‘A la sainte terre,’ ‘To the Holy Land.’ And so they became known as sainte-terre-ers or saunterers. Now these mountains are our Holy Land, and we ought to saunter through them reverently, not ‘hike’ through them.”

John Muir

 

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Foto: Dr. Eugenijus Kavaliauskas

http://www.dantis.net/x3/

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The environmental footprint of global food production  

Halpern et al., 2022

Feeding humanity puts enormous environmental pressure on our planet. These pressures are unequally distributed, yet we have piecemeal knowledge of how they accumulate across marine, freshwater and terrestrial systems. Here we present global geospatial analyses detailing greenhouse gas emissions, freshwater use, habitat disturbance and nutrient pollution generated by 99% of total reported production of aquatic and terrestrial foods in 2017. We further rescale and combine these four pressures to map the estimated cumulative pressure, or ‘footprint’, of food production. On land, we find five countries contribute nearly half of food’s cumulative footprint. Aquatic systems produce only 1.1% of food but 9.9% of the global footprint. Which pressures drive these footprints vary substantially by food and country. Importantly, the cumulative pressure per unit of food production (efficiency) varies spatially for each food type such that rankings of foods by efficiency differ sharply among countries. These disparities provide the foundation for efforts to steer consumption towards lower-impact foods and ultimately the system-wide restructuring essential for sustainably feeding humanity.

https://www.nature.com/articles/s41893-022-00965-x

Global food insecurity and famine from reduced crop, marine fishery and livestock production due to climate disruption from nuclear war soot injection  

Xia et al. 2022

Atmospheric soot loadings from nuclear weapon detonation would cause disruptions to the Earth’s climate, limiting terrestrial and aquatic food production. Here, we use climate, crop and fishery models to estimate the impacts arising from six scenarios of stratospheric soot injection, predicting the total food calories available in each nation post-war after stored food is consumed. In quantifying impacts away from target areas, we demonstrate that soot injections larger than 5 Tg would lead to mass food shortages, and livestock and aquatic food production would be unable to compensate for reduced crop output, in almost all countries. Adaptation measures such as food waste reduction would have limited impact on increasing available calories. We estimate more than 2 billion people could die from nuclear war between India and Pakistan, and more than 5 billion could die from a war between the United States and Russia—underlining the importance of global cooperation in preventing nuclear war.

https://www.nature.com/articles/s43016-022-00573-0

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Manipulación del microbioma como estrategia de adaptación al cambio climático en la agricultura sustentable   

Free energy principle 

 Karl Friston

Charles Jones 

(1866-1959)