sábado, 30 de noviembre de 2019

A global synthesis reveals biodiversity-mediated benefits for crop production       

Dainese et al., 2019


Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield–related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.



Distribution of analyzed studies and effects of richness on ecosystem services provisioning.(A) Map showing the size (number of crop fields sampled) and location of the 89 studies (further details of studies are given in table S1). (B) Global effect of pollinator richness on pollination (n = 821 fields of 52 studies). (C) Global effect of natural enemy richness on pest control (n = 654 fields of 37 studies). The thick line in each plot represents the median of the posterior distribution of the model. Light gray lines represent 1000 random draws from the posterior. The lines are included to depict uncertainty of the modeled relationship.

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jueves, 28 de noviembre de 2019

Los campos de trigo no me recuerdan nada y eso me pone triste.

El principito, Antoine de Saint-Exupéry.

miércoles, 27 de noviembre de 2019



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Written in the Trees: The Roots of Arborglyphs 

"Since earliest times, trees – symbolically anchored in the earth and stretched towards the cosmos – have been inherently connected with human identity.”

Words and symbols carved onto a living tree are sometimes described as ‘arborglyphs’ (derived from arbor ‘tree’; glyphein ‘to carve’), but some people think of it vandalism or ‘tree graffiti’. Whatever the name, tree writing is driven by multifarious social and cultural factors; love, solitude, rivalry, identity, artistry, boredom, or downright bragging.

Arborglyphs are present across many cultures. In Australia the Gamilaroi and Wiradjuri peoples carved ceremonial trees to connect with ancestors. The Scorpion Tree of the Chumash people is thought to be an astrological tool whilst the Moriori people on Chatham Islands carved symbols of the natural world and faces of their ancestors into kopi trees.

As agriculture developed over time carved trees become landscape noticeboards, trail-markers or shelter. For global romantics, the gesture of carving a lover’s initials into a tree appeared as far back as Ovid’s Heroides:

‘The beech trees guard my name, cut there by you;
and I read ‘Oenone’, written there by your knife.

And as the trunk grows, my name grows the same;
grow, and rise straight, in honour of my name!’



https://bit.ly/2yXWCxm
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lunes, 25 de noviembre de 2019

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Utsutsunaki tsumami gokoro no kocho kana

Nothing actual,
the feeling of holding in my fingers
a butterfly.
 

Yosa Buson
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Stick insect eggs
James Robertson 
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sábado, 23 de noviembre de 2019

Mapping the dynamics of research networks in ecology and evolution using co-citation analysis (1975–2015)  
Reale et al., 2019.


In this paper we used a co-citation network analysis to quantify and illustrate the dynamic patterns of research in ecology and evolution over 40 years (1975–2014). We addressed questions about the historical patterns of development of these two fields. Have ecology and evolution always formed a coherent body of literature? What ideas have motivated research activity in subfields, and how long have these ideas attracted the attention of the scientific community? Contrary to what we expected, we did not observe any trend towards a stronger integration of ecology and evolution into one big cluster that would suggest the existence of a single community. Three main bodies of literature have stayed relatively stable over time: population/community ecology, evolutionary ecology, and population/quantitative genetics. Other fields disappeared, emerged or mutated over time. Besides, research organization has shifted from a taxon-oriented structure to a concept-oriented one over the years, with researchers working on the same topics but on different taxa showing more interactions.


https://ecoevorxiv.org/dpef4/
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viernes, 22 de noviembre de 2019

Measuring What Matters: Actionable Information for Conservation Biocontrol in Multifunctional Landscapes 
Chaplin-Kramer et al., 2019


Despite decades of study, conservation biocontrol via manipulation of landscape elements has not become a mainstream strategy for pest control. Meanwhile, conservation groups and governments rarely consider the impacts of land management on pest control, and growers can even fear that conservation biocontrol strategies may exacerbate pest problems. By finding leverage points among these actors, there may be opportunities to align them to promote more widespread adoption of conservation biological control at the landscape-scale. But are ecologists measuring the right things and presenting the right evidence to enable such alignment? We articulate key concerns of growers, conservation groups, and governments with regards to implementing conservation biological control at the landscape scale and argue that if ecologists want to gain more traction, we need to reconsider what we measure, for what goals, and for which audiences. A wider set of landscape objectives that ecologists should consider in our measurements include risk management for growers and co-benefits of multifunctional landscapes for public actors. Ecologists need to shift our paradigm toward longer-term, dynamic measurements, and build cross-disciplinary understanding with socioeconomic and behavioral sciences, to enable better integration of the objectives of these diverse actors that will be necessary for landscape management for conservation biocontrol to achieve its full potential.


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jueves, 21 de noviembre de 2019

Venezuela 
Arbuckle Bros. Coffee Company, 1889. 3 x 5. Chromolithograph by Donaldson Brothers.

miércoles, 20 de noviembre de 2019

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Las mariposas tienen una gracia encantadora pero también son las criaturas más efímeras que existen. Nacidas quién sabe dónde, buscan dulcemente algunas pocas cosas y luego desaparecen silenciosamente en alguna parte. 

Haruki Murakami
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domingo, 17 de noviembre de 2019

The geographic scaling of biotic interactions 
Miguel B. Araújo Alejandro Rozenfeld


A central tenet of ecology and biogeography is that the broad outlines of species ranges are determined by climate, whereas the effects of biotic interactions are manifested at local scales. While the first proposition is supported by ample evidence, the second is still a matter of controversy. To address this question, we develop a mathematical model that predicts the spatial overlap, i.e. co‐occurrence, between pairs of species subject to all possible types of interactions. We then identify the scale of resolution in which predicted range overlaps are lost. We found that co‐occurrence arising from positive interactions, such as mutualism (+/+) and commensalism (+/0), are manifested across scales. Negative interactions, such as competition (−/−) and amensalism (−/0), generate checkerboard patterns of co‐occurrence that are discernible at finer resolutions but that are lost and increasing scales of resolution. Scale dependence in consumer–resource interactions (+/−) depends on the strength of positive dependencies between species. If the net positive effect is greater than the net negative effect, then interactions scale up similarly to positive interactions. Our results challenge the widely held view that climate alone is sufficient to characterize species distributions at broad scales, but also demonstrate that the spatial signature of competition is unlikely to be discernible beyond local and regional scales.


Expected co‐occurrence across biotic‐interaction space. Colours on the top graph indicate the intensity of the predicted co‐occurrence between species A (y axis) and B (x axis), where increasing gradients of red indicate increased co‐occurrence and increasing gradients of blue indicate decreased co‐occurrence. The light gray line indicates the portion of biotic‐interaction space where co‐occurrence between two species is no different than expected with the null model. The numbers on the y and x axes represent interactions (I) of varying signal (+, −, 0) and strength (≥ 0 ≤ 1). The lower scatter diagrams provide examples of simulated distributions of species A (black) and B (gray), with their respective co‐occurrence (red), for interactions of varying sign and strength. Both species have prevalence ρ= 0.3.

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The Isle of Fisherwoman 

https://bit.ly/2XJ16Hj
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sábado, 16 de noviembre de 2019

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The man has made the Earth a hell for animals

Arthur Schopenhauer
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jueves, 14 de noviembre de 2019

Sauromatum guttatum parenchyma cell, coloured transmission electron micrograph.   Note the cell wall, nucleus with nucleolus, amyloplast with starch grains and mitochondria.

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Effectiveness of agri‐environmental management on pollinators is moderated more by ecological contrast than by landscape structure or land‐use intensity 
Marja et al., 2019.


Agri‐environment management (AEM) started in the 1980s in Europe to mitigate biodiversity decline, but the effectiveness of AEM has been questioned. We hypothesize that this is caused by a lack of a large enough ecological contrast between AEM and non‐treated control sites. The effectiveness of AEM may be moderated by landscape structure and land‐use intensity. Here, we examined the influence of local ecological contrast, landscape structure and regional land‐use intensity on AEM effectiveness in a meta‐analysis of 62 European pollinator studies. We found that ecological contrast was most important in determining the effectiveness of AEM, but landscape structure and regional land‐use intensity played also a role. In conclusion, the most successful way to enhance AEM effectiveness for pollinators is to implement measures that result in a large ecological improvement at a local scale, which exhibit a strong contrast to conventional practices in simple landscapes of intensive land‐use regions.


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https://onlinelibrary.wiley.com/doi/pdf/10.1111/ele.13339
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The beauty of a flower comes from its roots

Ralph Waldo Emerson
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jueves, 7 de noviembre de 2019

A global synthesis reveals biodiversity-mediated benefits for crop production      
Dainese et al., 2019.


Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield–related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.


Distribution of analyzed studies and effects of richness on ecosystem services provisioning. (A) Map showing the size (number of crop fields sampled) and location of the 89 studies (further details of studies are given in table S1). (B) Global effect of pollinator richness on pollination (n = 821 fields of 52 studies). (C) Global effect of natural enemy richness on pest control (n = 654 fields of 37 studies). The thick line in each plot represents the median of the posterior distribution of the model. Light gray lines represent 1000 random draws from the posterior. The lines are included to depict uncertainty of the modeled relationship.

https://advances.sciencemag.org/content/5/10/eaax0121/tab-pdf
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Santa Cruz, Bolivia 
Deforestation for the expansion of mechanized agriculture and cattle ranching (17°23'15.7"S, 60°33'43.6"W)
Via: Anne-Marie Clark

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There's a whisper on the night-wind, there's a star agleam to guide us, 
And the Wild is calling, calling . . . let us go. 

Robert William Service
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