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)

 

Bruno Latour, el tejedor de redes

Elsa Gabriela Rodríguez y Diego Griffon

La mañana del 9 de octubre, nos sorprendió con la triste noticia de la muerte de Bruno Latour (Beaune, 1947 - París, 2022).  El intelectual francés más importante de inicios del siglo 21, deja un inmenso legado que abarca aportes fundamentales en filosofía, sociología y antropología. Con su excéntrica manera de estudiar y repensar el mundo, cuestionó implacablemente los dualismos propios del pensamiento moderno, instándonos a disolver las fronteras artificiales que la modernidad impone entre naturaleza y sociedad. 

Los no-humanos también actúan

 

Bruno Latour abandonó las concepciones antagónicas y jerárquicas entre humanos y no-humanos, incorporando de esta manera a las entidades no humanas en la teoría social. Para ello, supo hilar con bases sólidas (lejos de cualquier postura romántica o esencialista) una teoría (llamada del Actor-Red) y una metodología (Cartografía de Controversias) que reconoce y rastrea la capacidad de agencia de las entidades no-humanas.  Con Latour, lo social se convierte en un entramado de relaciones entre humanos-no humanos. Esta mirada irreverente, sentó las bases para un estudio de los fenómenos de una forma radicalmente diferente, particularmente pertinente en los tiempos de crisis que vivimos.

Gaia

 

Latour no se mantuvo ajeno al debate sobre el cambio climático y la crisis ecológica, sus últimas obras estuvieron dedicadas a la reflexión sobre estos temas. En ellas plantea ¿qué significa ser moralmente responsables en el Antropoceno, cuando la Tierra es modelada por nosotros? Para abordar esta pregunta incorporó en su análisis la Teoría de Gaia, reconociendo a Gaia como un entramado de entidades y relaciones, que nos abarca, sin que los humanos estemos plenamente conscientes de esto. Esta peligrosa ignorancia, fruto de las falsas divisiones entre lo social y natural, son en última instancia las responsables de los problemas ambientales actuales. Por lo tanto, la puerta de salida de la crisis se encuentra en hacernos conscientes de esta situación y de las responsabilidades que implica.

Legado

La obra de Latour es numerosa y profunda, a veces difícil de seguir, pero sin lugar a dudas relevante. Incluye múltiples temas y abordajes, siempre innovadores y a veces no valorados en su justa dimensión.  En este sentido, creemos que es realmente necesario que las ciencias biológicas aprovechen las gigantescas oportunidades que el marco teórico de Latour brinda y que las Sus libros nos presentan mundos extraños, aunque familiares, con abordajes innovadores y emocionantes.ciencias sociales le abran definitivamente las puertas principales de sus facultades.  Nada que podamos decir le hace realmente justicia, tal vez la mejor forma de terminar este homenaje sea con la voz del entrañable maestro: 

Anticipating drought-related food security changes  

Krishnamurthy et al., 2022

Food insecurity early warning can provide time to mitigate unfolding crises; however, drought remains a large source of uncertainty. The challenge is to filter unclear or conflicting signals from various climatic and socio-economic variables and link them to food security outcomes. Integrating lag-1 autocorrelation diagnostics into remotely sensed observations from the Soil Moisture Active Passive (SMAP) mission and food prices, we found dramatic improvement in anticipating the timing and intensity of food crises, except in conflict settings. We analysed drought-induced food crises globally in the SMAP record (since 2015; approximately five per year). The change in soil moisture autocorrelation, which we term the Soil Moisture Auto-Regressive Threshold (SMART), signalled an accurate food security transition for all cases studied here (P < 0.05; n = 212), including lead time of up to three to six months for every case. The SMART trigger anticipates the timing of the transition and the magnitude of the food security change among small to large transitions, both into and out of crises (R2 = 0.80–0.83). While we do not evaluate out-of-sample forecast accuracy using our model, our findings suggest a significant advancement in the capabilities of food security early-warning diagnostics and could save lives and resources.

https://www.nature.com/articles/s41893-022-00962-0

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Eremocene: the Age of Loneliness; the "miserable future" into which we are accelerating as a species, characterised by the existential & material isolation that comes from having calamitously extinguished other forms of life on Earth. 

Eremoceno: la Era de la Soledad; el "futuro miserable" hacia el que estamos acelerando como especie, caracterizado por el aislamiento existencial y material que proviene de haber extinguido calamitosamente otras formas de vida en la Tierra.

 

E.O. Wilson

Complex agricultural landscapes host more biodiversity than simple ones: A global meta-analysis 

Estrada-Carmona et al., 2022

Significance

Agricultural land, the world’s largest human-managed ecosystem, forms the matrix that connects remnant and fragmented patches of natural vegetation where nondomesticated biodiversity struggles to survive. Increasing the resources that this matrix can offer to biodiversity is critical to halting biodiversity loss. Our comprehensive meta-analysis demonstrates the positive and significant effect on biodiversity of increasing landscape complexity in agricultural lands. We found more biodiversity in complex landscapes, potentially contributing to agriculture production, ecosystem resilience, and human well-being. Current biodiversity conservation strategies tend to focus on natural ecosystems, often ignoring opportunities to boost biodiversity in agricultural landscapes. Our findings provide a strong scientific evidence base for managing agriculture at the landscape level for biodiversity synergistically conservation and sustainable production.

Abstract

Managing agricultural landscapes to support biodiversity conservation requires profound structural changes worldwide. Often, discussions are centered on management at the field level. However, a wide and growing body of evidence calls for zooming out and targeting agricultural policies, research, and interventions at the landscape level to halt and reverse the decline in biodiversity, increase biodiversity-mediated ecosystem services in agricultural landscapes, and improve the resilience and adaptability of these ecosystems. We conducted the most comprehensive assessment to date on landscape complexity effects on nondomesticated terrestrial biodiversity through a meta-analysis of 1,134 effect sizes from 157 peer-reviewed articles. Increasing landscape complexity through changes in composition, configuration, or heterogeneity significatively and positively affects biodiversity. More complex landscapes host more biodiversity (richness, abundance, and evenness) with potential benefits to sustainable agricultural production and conservation, and effects are likely underestimated. The few articles that assessed the combined contribution of linear (e.g., hedgerows) and areal (e.g., woodlots) elements resulted in a near-doubling of the effect sizes (i.e., biodiversity level) compared to the dominant number of studies measuring these elements separately. Similarly, positive effects on biodiversity are stronger in articles monitoring biodiversity for at least 2 y compared to the dominant 1-y monitoring efforts. Besides, positive and stronger effects exist when monitoring occurs in nonoverlapping landscapes, highlighting the need for long-term and robustly designed monitoring efforts. Living in harmony with nature will require shifting paradigms toward valuing and promoting multifunctional agriculture at the farm and landscape levels with a research agenda that untangles complex agricultural landscapes’ contributions to people and nature under current and future conditions.

https://bit.ly/3LjOlbL

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Global Warming 

John Harte

 

Global Warming John Harte, PhD from Central Colorado Humanists on Vimeo.

All of the rivers and waterways in South America, with coastlines, coloured according to the major hydrological basins they are part of and scaled by their size.

Via: PythonMaps

Community structure determines the predictability of population collapse 

Baruah et al., 2022.

1. Early warning signals (EWS) are phenomenological tools that have been proposed as predictors of the collapse of biological systems. Although a growing body of work has shown the utility of EWS based on either statistics derived from abundance data or shifts in phenotypic traits such as body size, so far this work has largely focused on single species populations.
2. However, to predict reliably the future state of ecological systems, which inherently could consist of multiple species, understanding how reliable such signals are in a community context is critical.
3. Here, reconciling quantitative trait evolution and Lotka–Volterra equations, which allow us to track both abundance and mean traits, we simulate the collapse of populations embedded in mutualistic and multi-trophic predator–prey communities. Using these simulations and warning signals derived from both population- and community-level data, we showed the utility of abundance-based EWS, as well as metrics derived from stability-landscape theory (e.g. width and depth of the basin of attraction), were fundamentally linked. Thus, the depth and width of such stability-landscape curves could be used to identify which species should exhibit the strongest EWS of collapse.
4. The probability a species displays both trait and abundance-based EWS was dependent on its position in a community, with some species able to act as indicator species. In addition, our results also demonstrated that in general trait-based EWS were less reliable in comparison with abundance-based EWS in forecasting species collapses in our simulated communities. Furthermore, community-level abundance-based EWS were fairly reliable in comparison with their species-level counterparts in forecasting species-level collapses.
5. Our study suggests a holistic framework that combines abundance-based EWS and metrics derived from stability-landscape theory that may help in forecasting species loss in a community context.

https://bit.ly/3BjTBZM

From the Critical Zone to the Anthropocene 

Bruno Latour

Como los Lobos Cambian los Rios

George Monbiot

Animal pollination increases stability of crop yield across spatial scales 

Bishop et al., 2022.

The benefits of animal pollination to crop yield are well known. In contrast, the effects of animal pollination on the spatial or temporal stability (the opposite of variability) of crop yield remain poorly understood. We use meta-analysis to combine variability information from 215 experimental comparisons between animal-pollinated and wind- or self-pollinated control plants in apple, oilseed rape and faba bean. Animal pollination increased yield stability (by an average of 32% per unit of yield) at between-flower, -plant, -plot and -field scales. Evidence suggests this occurs because yield benefits of animal pollination become progressively constrained closer to the maximum potential yield in a given context, causing clustering. The increase in yield stability with animal pollination is greatest when yield benefits of animal pollination are greatest, indicating that managing crop pollination to increase yield also increases yield stability. These additional pollination benefits have not yet been included in economic assessments but provide further justification for policies to protect pollinators.

https://bit.ly/3cFdtMx

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LOS ÁRBOLES

por Eugenio Montejo

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Hablan poco los árboles, se sabe.

Pasan la vida entera meditando

y moviendo sus ramas.

Basta mirarlos en otoño

cuando se juntan en los parques:

sólo conversan los más viejos,

los que reparten las nubes y los pájaros,

pero su voz se pierde entre las hojas

y muy poco nos llega, casi nada.

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Es difícil llenar un breve libro

con pensamientos de árboles.

Todo en ellos es vago, fragmentario.

Hoy, por ejemplo, al escuchar el grito

de un tordo negro, ya en camino a casa,

grito final de quien no aguarda otro verano,

comprendí que en su voz hablaba un árbol,

uno de tantos,

pero no sé qué hacer con ese grito,

no sé cómo anotarlo.

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Price Wars 

Rupert Russell 

In memoriam

James Lovelock 

(1919-2022)

https://en.wikipedia.org/wiki/James_Lovelock

 

Aprendizaje automático para ciencias ecológicas y gestión de ecosistemas 

Thomas G. Dietterich 

Agricultural management and pesticide use reduce the functioning of beneficial plant symbionts  

Edlinger et al., 2022

Phosphorus (P) acquisition is key for plant growth. Arbuscular mycorrhizal fungi (AMF) help plants acquire P from soil. Understanding which factors drive AMF-supported nutrient uptake is essential to develop more sustainable agroecosystems. Here we collected soils from 150 cereal fields and 60 non-cropped grassland sites across a 3,000 km trans-European gradient. In a greenhouse experiment, we tested the ability of AMF in these soils to forage for the radioisotope 33P from a hyphal compartment. AMF communities in grassland soils were much more efficient in acquiring 33P and transferred 64% more 33P to plants compared with AMF in cropland soils. Fungicide application best explained hyphal 33P transfer in cropland soils. The use of fungicides and subsequent decline in AMF richness in croplands reduced 33P uptake by 43%. Our results suggest that land-use intensity and fungicide use are major deterrents to the functioning and natural nutrient uptake capacity of AMF in agroecosystems.

@vandeHeijdenLab: 

Unseen and hidden effects of pesticides: pesticide suppress natural soil fertilizers.  Our new study  demonstrates that pesticides suppress the natural nutrient uptake capacity of beneficial mycorrhizal fungi with 42%.

This result is important because 70% of all land plants and many crops form a beneficial symbiosis with mycorrhizal fungi. The fungi supply nutrients to the plant in return for sugars and fatty acids. They do this through highly sophisticated arbuscules in plant cells.

This study confirms our previous study showing that the abundance of beneficial mycorrhizal fungi is strongly and negatively linked to the number of pesticides in arable soils. 

Pesticide effects worked in two ways: the diversity and richness of mycorrhizal fungi was 50% lower in plots where fungicides had been applied and fungicides reduced the natural nutrient uptake capacity. 

We already found out that synthetic pesticides are widespread in soil and we found up to 16 different pesticides after 20 years of organic management – and we only analysed 46 pesticides far less as the number being applied.

A large study across Germany even demonstrated that all air samples analysed contained pesticides. Up to 36 different pesticide compounds were detected in the air, including pesticides not approved for use anymore.

In Switzerland pesticides are also found in drinking water, especially in areas with intensive agricultural production. Many people are concerned about potential health effects.

These findings are not surprising. Large amounts of pesticides are used worldwide and in some countries, over 20 kg per hectare and year are applied. With a 50% increase in pesticides use since the 90ies.

Pesticide use varies strongly among crops. For some crops (fruit-trees, vinyards) >25 kg of pesticides are applied per hectare and year, which is a lot. For others (grassland) hardly any pesticide are applied.

Farmers apply pesticides because they often work very well against pests and diseases. It is logical that farmers apply pesticides because they help to secure yield and food security. However, many crops can be grown without pesticides.

For many crops there are cultivars that are (largely) resistant to disease and with appropriate farming practices (e.g. crop rotation, mixed cropping) and weed control measures it is possible to drastically reduce pesticide use without yield or income loss.

Also organic farmers apply pesticides, but only those that are not synthetic and produced in nature. Still, some of these organically certified pesticides are harmful. However, negative effects are usually (not always) much lower compared to synthetic pesticides.

Interestingly >150 different synthetic pesticides have been banned in Switzerland between 2005 & 2020 (source BLW).

Society is more and more critical about the use of pesticides and this is reflecting in increased consumption of organic and pesticide free produced products (a growth of >50% in 5 years). In Switzerland 17% of agricultural land is under organic management (source Biosuisse).

I assume that (big) companies selling synthetic #pesticides are getting nervous because their business model is under pressure when more and more farmers move to organic or pesticide free production.

It is logical that companies sell synthetic pesticides because there is still a big market and a large demand. What is very questionable is that several companies sell and produce pesticides that have been banned in many countries (e.g. CH, EU) because they are very harmful.

As long as such companies do sell banned pesticides, simply to make profit, there are no arguments to trust such companies, even if they focus more on sustainability, soil health or biodiversity.

This tweet thread is written by Marcel van der Heijden (Professor for Agroecology) and these comments reflect my personal opinion, not necessarily those of Agroscope, University of Zurich or Utrecht University.

https://www.nature.com/articles/s41559-022-01799-8

 Chaos in ecology is more common than you think

We find evidence for chaos in over 30% of time series in an ecological database using updated, flexible, and rigorously tested algorithms. Lack of evidence for chaos in prior meta-analyses is likely the result of methodological and data limitations, rather than inherent stability.

Systems that are 'chaotic' are sensitive to small changes in initial conditions, and are predictable in the short term, but not in the long term. The weather is an example of a chaotic system - it is completely governed by the rules of physics, but difficult to predict accurately beyond several days. This is in contrast to 'stable' dynamics, which are predictable over long periods, or 'random' fluctuations, which are not predictable over any time horizon. Populations in nature fluctuate a great deal, and knowing whether these fluctuations are regular, chaotic, or random has major implications for how well (and how far into the future) we can predict population sizes, and how they will respond to management interventions.  

Chaos was first introduced to ecology in the 1970s, and there was great interest in whether the seemingly erratic population fluctuations we see in nature could be explained by relatively simple (single species) chaotic population models. However, by the late 1990s, it had become increasingly clear that this wasn’t the case. Chaos detection studies based on these simple models found little evidence for chaos in field data, and the idea that chaos is rare in ecology became increasingly widespread. 

Source: https://go.nature.com/3bwHoGe

Research paper:

Chaos is not rare in natural ecosystems  

Chaotic dynamics are thought to be rare in natural populations but this may be due to methodological and data limitations, rather than the inherent stability of ecosystems. Following extensive simulation testing, we applied multiple chaos detection methods to a global database of 172 population time series and found evidence for chaos in >30%. In contrast, fitting traditional one-dimensional models identified <10% as chaotic. Chaos was most prevalent among plankton and insects and least among birds and mammals. Lyapunov exponents declined with generation time and scaled as the −1/6 power of body mass among chaotic populations. These results demonstrate that chaos is not rare in natural populations, indicating that there may be intrinsic limits to ecological forecasting and cautioning against the use of steady-state approaches to conservation and management.

Rogers et al., 2022. https://www.nature.com/articles/s41559-022-01787-y

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Holobiont Evolution: Population Theory for the Hologenome 

Joan Roughgarden

 

The multiplexity of ecological communities

Sonia Kéfi 

¿Conoces el Conuco?

Principles of Biological Design -  Order, Disorder, Complexity

Ricard Solé

 Can we create the "perfect" farm? 

Sustainable agricultural practices contribute significantly to One Health 

Yan et al., 2022.

The One Health concept proposes that the health of humans, animals, and the environment are interconnected. Agricultural production is a critical component of One Health as food links the environment to human health. Food not only provides nutrients to humans but also represents an important pathway for human exposure to environmental microbes as well as potentially harmful agrochemicals. In addition, inappropriate agronomic practices can cause damage to the environment which can have unintended adverse impacts on human health. Therefore, improving agricultural production systems and protecting environmental health should not be viewed as isolated goals as they are strongly interlinked. Here, we used the nexus of soil, plant, and human microbiomes to discuss sustainable agricultural production from the One Health perspective. We highlighted three interconnected challenges faced by current agronomic practices: the transmissions of pathogens in soil-human microbial loops, the dissemination of antibiotic resistance genes in agroecosystems, and the impacts of chemical pesticides on humans and environmental health. Finally, we propose the potential of utilising microbiomes for better sustainable agronomic practices to contribute to key goals of the One Health concept.

https://onlinelibrary.wiley.com/doi/full/10.1002/sae2.12019

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A keystone gene underlies the persistence of an experimental food web

Barbour et al., 2022. 

In the past few decades, the identification of keystone species, that is, those with essential roles in structuring a community or ecosystem, has increased across systems. Barbour et al. extended this concept to genes, showing that a single allele of a particular plant defense gene facilitates species coexistence across a small experimental trophic system. Specifically, plants with this allele grew faster, supporting larger populations of two species of herbivores and their predators. This finding suggests that genotype variation can play a role in the structure and function of organismal systems. 

Genes encode information that determines an organism’s fitness. Yet we know little about whether genes of one species influence the persistence of interacting species in an ecological community. Here, we experimentally tested the effect of three plant defense genes on the persistence of an insect food web and found that a single allele at a single gene promoted coexistence by increasing plant growth rate, which in turn increased the intrinsic growth rates of species across multiple trophic levels. Our discovery of a “keystone gene” illustrates the need to bridge between biological scales, from genes to ecosystems, to understand community persistence.

https://www.science.org/doi/epdf/10.1126/science.abf2232

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Landscape complexity and functional groups moderate the effect of diversified farming on biodiversity: A global meta-analysis  

Sánchez et al., 2022.

Homogenisation and intensification of agricultural ecosystems are among the most important threats to biodiversity, linked to declines in pollinators, soil biota and ecosystem functioning. Diversification has been proposed as a way to restore ecosystem functioning in agricultural landscapes. To manage agricultural land for multiple ecosystem functions, evidence is needed of the effect of diversification on functionally distinct taxa. We contribute to closing this knowledge gap through a global meta-analysis of 161 peer-reviewed articles addressing the abundance and richness of six distinct functional groups: autotrophs, decomposers, natural enemies, pests, pollinators, and other. We found diversified farming systems increased overall species richness by 26% on average, relative to simplified farming systems. However, the effect of diversified farming on the overall mean abundance was weak. Our study shows diversified farming systems enhanced the abundance and richness of beneficial species while reducing the abundance of pests (e.g., weeds, herbivores), thus providing benefits for both agricultural production and biodiversity. The positive effect of diversified farming systems on the overall mean species richness was stronger in farms in more simplified landscapes, i.e., those that are further from natural and semi-natural habitats or have a lower proportion of seminatural vegetation in a 1 km radius. Pollinator’s abundance and richness were highest in diversified farming plots located far away from natural and semi-natural habitats. In contrast, proximity to these natural and semi-natural habitats (<250 m) increased the positive effect of diversified farming systems on natural enemies’ abundance, while reducing the number of pests. Our results add to the body of evidence calling for the repurposing of policies, regulations, and international agendas to promote, support and incentivize the adoption of diversified farming practices for supporting biodiversity. Spatial planning of diversification schemes should consider the landscape context of farms to ensure the greatest benefit of intervention.

Mean effect size of farming systems (diversified vs. simplified) on abundance from the interaction between functional groups and: A) the percentage of landscape covered by natural and semi-natural habitats; B) land cover Shannon's diversity index; C) categorical variables for the nearest Euclidean distance to natural or semi-natural habitat. Lines and dots = mean effect sizes in LRR. Error bars = [ ± 95% CI]. *Mean effect size significantly different from zero

$\mathrm{}\mathrm{}$.

https://doi.org/10.1016/j.agee.2022.107933

Machine Learning and Deep Learning -- A review for Ecologists  

Maximilian Pichler, Florian Hartig, 2022.

The popularity of Machine learning (ML), Deep learning (DL), and Artificial intelligence (AI) has sharply risen in recent years. Despite their spike in popularity, the inner workings of ML and DL algorithms are perceived as opaque, and their relationship to classical data analysis tools remains debated. It is often assumed that ML and DL excel primarily at making predictions. Recently, however, they have been increasingly used for classical analytical tasks traditionally covered by statistical models. Moreover, recent reviews on ML have focused exclusively on DL, missing out on synthesizing the wealth of ML algorithms with different advantages and general principles. Here, we provide a comprehensive overview of ML and DL, starting with their historical developments, their algorithm families, their differences from traditional statistical tools, and universal ML principles. We then discuss why and when ML and DL excel at prediction tasks, and where they could offer alternatives to traditional statistical methods for inference, highlighting current and emerging applications for ecological problems. Finally, we summarize emerging trends, particularly scientific and causal ML, explainable AI, and responsible AI that may significantly impact ecological data analysis in the future.

https://arxiv.org/abs/2204.05023

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Permanence via invasion graphs: Incorporating community assembly into Modern Coexistence Theory  

Josef Hofbauer, Sebastian J. Schreiber, 2022.

To understand the mechanisms underlying species coexistence, ecologists often study invasion growth rates of theoretical and data-driven models. These growth rates correspond to average per-capita growth rates of one species with respect to an ergodic measure supporting other species. In the ecological literature, coexistence often is equated with the invasion growth rates being positive. Intuitively, positive invasion growth rates ensure that species recover from being rare. To provide a mathematically rigorous framework for this approach, we prove theorems that answer two questions: (i) When do the signs of the invasion growth rates determine coexistence? (ii) When signs are sufficient, which invasion growth rates need to be positive? We focus on deterministic models and equate coexistence with permanence, i.e., a global attractor bounded away from extinction. For models satisfying certain technical assumptions, we introduce invasion graphs where vertices correspond to proper subsets of species (communities) supporting an ergodic measure and directed edges correspond to potential transitions between communities due to invasions by missing species. These directed edges are determined by the signs of invasion growth rates. When the invasion graph is acyclic (i.e. there is no sequence of invasions starting and ending at the same community), we show that permanence is determined by the signs of the invasion growth rates. In this case, permanence is characterized by the invasibility of all -i communities, i.e., communities without species i where all other missing species having negative invasion growth rates. We show that dissipative Lotka-Volterra models satisfy our technical assumptions and computing their invasion graphs reduces to solving systems of linear equations. We provide additional applications of the results and discuss open problems.

https://arxiv.org/abs/2204.03773

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 El girasol, 1907, Gustav Klimt

Language of fungi derived from their electrical spiking activity 

Andrew Adamatzky, 2022.

Fungi exhibit oscillations of extracellular electrical potential recorded via differential electrodes inserted into a substrate colonized by mycelium or directly into sporocarps. We analysed electrical activity of ghost fungi (Omphalotus nidiformis), Enoki fungi (Flammulina velutipes), split gill fungi (Schizophyllum commune) and caterpillar fungi (Cordyceps militaris). The spiking characteristics are species specific: a spike duration varies from 1 to 21 h and an amplitude from 0.03 to 2.1 mV. We found that spikes are often clustered into trains. Assuming that spikes of electrical activity are used by fungi to communicate and process information in mycelium networks, we group spikes into words and provide a linguistic and information complexity analysis of the fungal spiking activity. We demonstrate that distributions of fungal word lengths match that of human languages. We also construct algorithmic and Liz-Zempel complexity hierarchies of fungal sentences and show that species S. commune generate the most complex sentences.

https://royalsocietypublishing.org/doi/10.1098/rsos.211926

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