scholarly journals Natural selection on a carbon cycling trait drives ecosystem engineering by Sphagnum (peat moss)

2021 ◽  
Vol 288 (1957) ◽  
pp. 20210609
Author(s):  
Bryan T. Piatkowski ◽  
Joseph B. Yavitt ◽  
Merritt R. Turetsky ◽  
A. Jonathan Shaw
Keyword(s):  
Natural Selection ◽  
Carbon Cycling ◽  
Niche Differentiation ◽  
Interspecific Variation ◽  
Ecosystem Engineering ◽  
Peat Moss ◽  
Sphagnum Peat Moss ◽  
Extant Species

Sphagnum peat mosses have an extraordinary impact on the global carbon cycle as they control long-term carbon sequestration in boreal peatland ecosystems. Sphagnum species engineer peatlands, which harbour roughly a quarter of all terrestrial carbon, through peat accumulation by constructing their own niche that allows them to outcompete other plants. Interspecific variation in peat production, largely resulting from differences in tissue decomposability, is hypothesized to drive niche differentiation along microhabitat gradients thereby alleviating competitive pressure. However, little empirical evidence exists for the role of selection in the creation and maintenance of such gradients. In order to document how niche construction and differentiation evolved in Sphagnum , we quantified decomposability for 54 species under natural conditions and used phylogenetic comparative methods to model the evolution of this carbon cycling trait. We show that decomposability tracks the phylogenetic diversification of peat mosses, that natural selection favours different levels of decomposability corresponding to optimum niche and that divergence in this trait occurred early in the evolution of the genus prior to the divergence of most extant species. Our results demonstrate the evolution of ecosystem engineering via natural selection on an extended phenotype, of a fundamental ecosystem process, and one of the Earth's largest soil carbon pools.

scholarly journals Adding fossil occupancy trajectories to the assessment of modern extinction risk

2016 ◽  
Vol 12 (10) ◽  
pp. 20150813 ◽  
Author(s):  
Wolfgang Kiessling ◽  
Ádám T. Kocsis
Keyword(s):  
Fossil Record ◽  
Extinction Risk ◽  
Strong Predictor ◽  
Marine Species ◽  
Species Traits ◽  
Latent Extinction ◽  
Extant Species ◽  
Temporal Trajectory

Besides helping to identify species traits that are commonly linked to extinction risk, the fossil record may also be directly relevant for assessing the extinction risk of extant species. Standing geographical distribution or occupancy is a strong predictor of both recent and past extinction risk, but the role of changes in occupancy is less widely assessed. Here we demonstrate, based on the Cenozoic fossil record of marine species, that both occupancy and its temporal trajectory are significant determinants of risk. Based on extinct species we develop a model on the additive and interacting effects of occupancy and its temporal changes on extinction risk. We use this model to predict extinction risk of extant species. The predictions suggest a moderate risk for marine species on average. However, some species seem to be on a long-term decline and potentially at a latent extinction risk, which is not considered in current risk assessments.

scholarly journals The signature of competition in ecomorphological traits across the avian radiation

2020 ◽  
Vol 287 (1938) ◽  
pp. 20201585
Author(s):  
A. M. Chira ◽  
C. R. Cooney ◽  
J. A. Bright ◽  
E. J. R. Capp ◽  
E. C. Hughes ◽  
...  
Keyword(s):  
Species Interactions ◽  
Biological Diversity ◽  
Phenotypic Evolution ◽  
Shared Resources ◽  
Deep Time ◽  
Extant Species ◽  
Phenotypic Diversification ◽  
Best Fit

Competition for shared resources represents a fundamental driver of biological diversity. However, the tempo and mode of phenotypic evolution in deep-time has been predominantly investigated using trait evolutionary models which assume that lineages evolve independently from each other. Consequently, the role of species interactions in driving macroevolutionary dynamics remains poorly understood. Here, we quantify the prevalence for signatures of competition between related species in the evolution of ecomorphological traits across the bird radiation. We find that mechanistic trait models accounting for the effect of species interactions on phenotypic divergence provide the best fit for the data on at least one trait axis in 27 out of 59 clades ranging between 21 and 195 species. Where it occurs, the signature of competition generally coincides with positive species diversity-dependence, driven by the accumulation of lineages with similar ecologies, and we find scarce evidence for trait-dependent or negative diversity-dependent phenotypic evolution. Overall, our results suggest that the footprint of interspecific competition is often eroded in long-term patterns of phenotypic diversification, and that other selection pressures may predominantly shape ecomorphological diversity among extant species at macroevolutionary scales.

scholarly journals ROLE OF PERLITE IN FLUORIDE TOXICITY OF FLORAL CROPS

HortScience ◽  
1994 ◽  
Vol 29 (7) ◽  
pp. 728e-728
Author(s):  
Tammy L. Everett ◽  
Paul V. Nelson
Keyword(s):  
Sodium Phosphate ◽  
Peat Moss ◽  
Fluoride Toxicity ◽  
The North ◽  
Sodium Phosphate Buffer ◽  
Sphagnum Peat Moss ◽  
Chlorophytum Comosum ◽  
Asiatic Hybrids ◽  
Substrate Ph

Five common sources of perlite used in the North American horticultural industry were tested for their release of fluoride during five successive teachings with pH 5.2 sodium phosphate buffer (1 cc perlite/ml buffer). Soluble fluoride in the first leachate ranged from 0.05 to 0.8 mg/l and in the fifth leachate from 0.01 to 0.18 mg/l. Lilium Asiatic hybrids `Pixie Grange' and `Sunray', Chlorophytum comosum (Thumb.) Jacques `Variegatum', and Gibasis pellucida (Martens & Gal.) D. Hunt `Bridal Veil' were. grown in sphagnum peat moss plus perlite substrates ranging up to 50% perlite and at substrate pH levels from 4.6 to 7.0. No fluoride toxicity occurred in these crops in any treatments. The precaution against the use of perlite in substrates used for growing fluoride sensitive crops needs to be reconsidered.

Abusive head trauma (AHT) outcome at long-term follow-up and the role of elective neurosurgical approach: A report of 22 cases

2013 ◽  
Author(s):  
Francesca Menegazzo ◽  
Melissa Rosa Rizzotto ◽  
Martina Bua ◽  
Luisa Pinello ◽  
Elisabetta Tono ◽  
...  
Keyword(s):  
Head Trauma ◽  
Abusive Head Trauma ◽  
Long Term Follow Up

The Second Start of Transformation in Ukraine?

2014 ◽  
pp. 30-52 ◽  
Author(s):  
L. Grigoryev ◽  
E. Buryak ◽  
A. Golyashev
Keyword(s):  
Economic Growth ◽  
Armed Conflict ◽  
Political Crisis ◽  
Investment Climate ◽  
Institutional Reforms ◽  
Personal Consumption ◽  
Governance Quality ◽  
Political Turmoil

The Ukrainian socio-economic crisis has been developing for years and resulted in the open socio-political turmoil and armed conflict. The Ukrainian population didn’t meet objectives of the post-Soviet transformation, and people were disillusioned for years, losing trust in the state and the Future. The role of workers’ remittances in the Ukrainian economy is underestimated, since the personal consumption and stability depend strongly on them. Social inequality, oligarchic control of key national assets contributed to instability as well as regional disparity, aggravated by identity differences. Economic growth is slow due to a long-term underinvestment, and prospects of improvement are dependent on some difficult institutional reforms, macro stability, open external markets and the elites’ consensus. Recovering after socio-economic and political crisis will need not merely time, but also governance quality improvement, institutions reform, the investment climate revival - that can be attributed as the second transformation in Ukraine.

Thoughts on the Long-Term Strategy, Science and Democracy

2006 ◽  
pp. 4-19 ◽  
Author(s):  
L. Abalkin
Keyword(s):  
Strategy Development ◽  
Russian Science ◽  
Global Trends ◽  
The World ◽  
World Development ◽  
Crucial Condition

The article covers unified issues of the long-term strategy development, the role of science as well as democracy development in present-day Russia. The problems of budget proficit, the Stabilization Fund issues, implementation of the adopted national projects, an increasing role of regions in strengthening the integrity and prosperity of the country are analyzed. The author reveals that the protection of businessmen and citizens from the all-embracing power of bureaucrats is the crucial condition of democratization of the society. Global trends of the world development and expert functions of the Russian science are presented as well.

Development of Social and Economic Forecasting and Ideas of A. Anchishkin

2013 ◽  
pp. 143-155
Author(s):  
A. Klepach ◽  
G. Kuranov
Keyword(s):  
Economic Planning ◽  
Special Role ◽  
Economic Management ◽  
Economic Forecasting ◽  
Russian Economy ◽  
World Economic ◽  
Long Term Forecasting ◽  
Working Out

The role of the prominent Soviet economist, academician A. Anchishkin (1933—1987), whose 80th birth anniversary we celebrate this year, in the development of ideas and formation of economic forecasting in the country at the time when the directive planning acted as a leading tool of economic management is explored in the article. Besides, Anchishkin’s special role is noted in developing a comprehensive program of scientific and technical progress, an information basis for working out long-term forecasts of the country’s development, moreover, his contribution to the creation of long-term forecasting methodology and improvement of the statistical basis for economic analysis and economic planning. The authors show that social and economic forecasting in the period after 1991, which has undertaken a number of functions of economic planning, has largely relied on further development of Anchishkin’s ideas, at the same time responding to new challenges for the Russian economy development during its entry into the world economic system.

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