Biological stoichiometry: a theoretical framework connecting ecosystem ecology, evolution, and biochemistry for application in astrobiology

2003 ◽  
Vol 2 (3) ◽  
pp. 185-193 ◽  
Author(s):  
James J. Elser

Astrobiology is an extremely wide-ranging field and thus is in special need of conceptual and theoretical frameworks that can integrate its various arenas of study. In this paper I review recent work associated with a conceptual framework known as ‘ecological stoichiometry’ and even more recent extensions in the development of ‘biological stoichiometry’. Ecological stoichiometry is the study of the balance of energy and multiple chemical elements in ecological interactions and has developed rapidly in the study of nutrient cycling and energy flow in aquatic food webs. It identifies the elemental composition of interacting biota as central in understanding the nature of their interactions and dynamics, including key feedbacks via nutrient recycling. Biological stoichiometry extends this mode of thinking to all types of biological systems. It especially seeks to better understand, at the biochemical and genetic levels, the factors influencing the elemental composition of living things and the evolutionary forces that drive and constrain that elemental composition. By connecting key concepts of ecosystem ecology, evolutionary biology and biochemistry, stoichiometric theory integrates biological information into a more coherent whole that holds considerable promise for application in astrobiology. Several examples of potential astrobiological applications of stoichiometric analysis are offered, including ones related to pre-biotic evolution, the Cambrian explosion, biosignatures and biological feedbacks on planetary carbon cycling.

2021 ◽  
pp. 51-56
Author(s):  
Yu. B. Sazonov ◽  
D. Yu. Ozherelkov ◽  
R. Sh. Latypov ◽  
E. E. Gorshkov

Possibility of determination of the fragments and articles made of different grades of steel aluminium and copper alloys and their affiliation to the common melt was examined via the methods of photoelectric spectral analysis based on composition of micro-impurities. Chemical elements with micro-impurities were revealed; they allow to determine affiliation of metal fragments to one melt. Ultimately possible deviations of micro-impurities within one melt were obtained. The technique allowing to establish affiliation of fragments to the common melt based on their elementary composition of micro-impurities with minimal amount of measurements was suggested based on the obtained results. The minimal geometric size of a sample available for analysis was determined; it allows to classify the examined fragments to one melt based on the results of investigation of expanded elementary composition of micro-impurities. Practical opportunities of this technique were displayed on the example of the alloys with different chemical composition.


Author(s):  
Vladimir L. Gavrikov ◽  
◽  
Alexey I. Fertikov ◽  
Evgenii A. Vaganov ◽  

Distribution of chemical elements in tree rings bears important information on various biogeochemical processes. In order to achieve a reliable interpretation of the information, it is necessary to know the degree of variation in the content of chemical elements both at the level of the entire species and at the level of individual trees. The research aims to determine which chemical elements have a stable distribution in the trunks of a number of conifers: Siberian spruce (Picea obovata Ledeb.), Scots pine (Pinus sylvestris L.), Siberian larch (Larix sibirica Ledeb.), and Siberian pine (Pinus sibirica Du Tour). The data for the analysis were obtained on the basis of the long-term experiment in forest growing. The experimental site was laid out in 1971–1972 in the vicinity of Krasnoyarsk by the staff of the Sukachev Institute of Forest of the Siberian Branch of the Russian Academy of Sciences. Before planting the seedlings, the soil ground was mechanically levelled, and thus, sufficiently equal growth conditions were created for all plantings. Cores with a diameter of 12 mm were sampled from three normally developing trees of each species and analyzed using modern X-ray fluorescence methods. Content relative values of elements (counts) were obtained with the Itrax Multiscanner (COX Analytical Systems). The content of elements in the tree rings was characterized by the concentration and reserve of elements. Concentration was calculated as the number of counts per 1 mm2 of the ring area; reserve was calculated as the number of counts over the entire ring area. Each of these variables was defined by the parameters of linear slope in the calendar year series and the standard deviation. The cluster analysis was performed in the 4-dimensional space of the obtained parameters. This allowed determining whether the series of element distributions from different trees and species are grouped. Three elements (Ca, Co, and P) show high stability of distribution parameters in tree rings with no regard to tree species. A number of other elements (Mn, Pb, Cl, Cr, Ni, Sr, and W) are stably grouped depending on the species. The results of the research enable to focus on the study of the elements stably distributed in the conifer trunks. For citation: Gavrikov V.L., Fertikov A.I., Sharafutdinov R.A., Vaganov E.A. Variability in Elemental Composition of Conifer Tree Rings. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 24–37. DOI: 10.37482/0536-1036-2021-6-24-37


Author(s):  
Olga Belykh ◽  
Elena Chuparina

The article is dedicated to the issues of sustainable development of territories with cumulative environmental damage on the basis of improving environmental analysis techniques of forest ecosystems health in Baikal region. The authors discuss the processes related to degradation of dark coniferous forests due to the emissions of pulp and paper industry. The factors affecting the development and producing capacity of forest stand are pointed out, namely highly acidic soil and heavy metals pollution. The data obtained by X-ray fluorescence analysis of needles are presented. They prove the presence of 20 chemical elements in the forest forming species of Pinaceae: Abies sibirica, Pinus sylvestris, Pinus sibirica, Picea obovata. The elemental composition of needles after the enterprise was closed is not over the exposure limit for conditionally toxic elements. The territory where the research was carried out is suitable for agriculture, tourism and recreational activities. The obtained data were used to implement new techniques of inspecting forest vegetation health.


2022 ◽  
Vol 1048 ◽  
pp. 423-428
Author(s):  
Heber Nehemias Chui-Betancur ◽  
Dwight R. Acosta ◽  
German Belizario-Quispe ◽  
Roberto Alfaro-Alejo

Geophagists are generally defined by culture, social status and gender, and this paper is to identify the chemical elements of the geophagic material called Machu Rumi. The sample was extracted from the center of the geophagic material. Two micrographs were observed, the 1c micrograph contains: O (8.63%), Al (14.85%), SiO2 (33.07%), Fe (5.93%), K (5.36%), Mg (1.37 %) and Ca (0.81%), these elements are characteristics of the clay minerals, the 1d micrograph, contains: oxygen 62.14%, Silicon 37.80% and Aluminum 0.06%, these elements are present in the clay minerals soils. The results of elemental composition and micromorphology reveals the presence of phyllosilicates, SiO2, Fe, K, Mg, Ca, and Al so the consumption of Machu Rumi would contribute to the benefic geophagy.


2019 ◽  
Vol 374 (1774) ◽  
pp. 20180370 ◽  
Author(s):  
Salva Duran-Nebreda ◽  
George W. Bassel

Information processing and storage underpins many biological processes of vital importance to organism survival. Like animals, plants also acquire, store and process environmental information relevant to their fitness, and this is particularly evident in their decision-making. The control of plant organ growth and timing of their developmental transitions are carefully orchestrated by the collective action of many connected computing agents, the cells, in what could be addressed as distributed computation. Here, we discuss some examples of biological information processing in plants, with special interest in the connection to formal computational models drawn from theoretical frameworks. Research into biological processes with a computational perspective may yield new insights and provide a general framework for information processing across different substrates.This article is part of the theme issue ‘Liquid brains, solid brains: How distributed cognitive architectures process information’.


2019 ◽  
Vol 374 (1774) ◽  
pp. 20180369 ◽  
Author(s):  
Santosh Manicka ◽  
Michael Levin

Brains exhibit plasticity, multi-scale integration of information, computation and memory, having evolved by specialization of non-neural cells that already possessed many of the same molecular components and functions. The emerging field of basal cognition provides many examples of decision-making throughout a wide range of non-neural systems. How can biological information processing across scales of size and complexity be quantitatively characterized and exploited in biomedical settings? We use pattern regulation as a context in which to introduce the Cognitive Lens—a strategy using well-established concepts from cognitive and computer science to complement mechanistic investigation in biology. To facilitate the assimilation and application of these approaches across biology, we review tools from various quantitative disciplines, including dynamical systems, information theory and least-action principles. We propose that these tools can be extended beyond neural settings to predict and control systems-level outcomes, and to understand biological patterning as a form of primitive cognition. We hypothesize that a cognitive-level information-processing view of the functions of living systems can complement reductive perspectives, improving efficient top-down control of organism-level outcomes. Exploration of the deep parallels across diverse quantitative paradigms will drive integrative advances in evolutionary biology, regenerative medicine, synthetic bioengineering, cognitive neuroscience and artificial intelligence. This article is part of the theme issue ‘Liquid brains, solid brains: How distributed cognitive architectures process information’.


2010 ◽  
Vol 365 (1557) ◽  
pp. 3469-3483 ◽  
Author(s):  
Michael Kearney ◽  
Stephen J. Simpson ◽  
David Raubenheimer ◽  
Brian Helmuth

The niche concept is central to ecology but is often depicted descriptively through observing associations between organisms and habitats. Here, we argue for the importance of mechanistically modelling niches based on functional traits of organisms and explore the possibilities for achieving this through the integration of three theoretical frameworks: biophysical ecology (BE), the geometric framework for nutrition (GF) and dynamic energy budget (DEB) models. These three frameworks are fundamentally based on the conservation laws of thermodynamics, describing energy and mass balance at the level of the individual and capturing the prodigious predictive power of the concepts of ‘homeostasis’ and ‘evolutionary fitness’. BE and the GF provide mechanistic multi-dimensional depictions of climatic and nutritional niches, respectively, providing a foundation for linking organismal traits (morphology, physiology, behaviour) with habitat characteristics. In turn, they provide driving inputs and cost functions for mass/energy allocation within the individual as determined by DEB models. We show how integration of the three frameworks permits calculation of activity constraints, vital rates (survival, development, growth, reproduction) and ultimately population growth rates and species distributions. When integrated with contemporary niche theory, functional trait niche models hold great promise for tackling major questions in ecology and evolutionary biology.


2019 ◽  
Vol 11 (2) ◽  
pp. 37
Author(s):  
S. Batbileg ◽  
B. Purevsuren ◽  
M. Battsetseg ◽  
A. Ankhtuya ◽  
D. Batkhishig

Have been determined the technical characteristics and elemental composition of shells. The elemental composition of the shell was determined by a microanalytical method such as 5Е С2000 model CNH-analyzer. The pyrolysis of shells investigated by using a standard quartz retort (tube) at different heating temperatures and determined the yields of pyrolysis products such as hard residue, tar, pyrolytic water, and gas. As a result of these experiments have been determined that 30% hard residue, higher yield 13% of tar, can be obtained at heating temperature 500oC. Thermogravimetric analysis of shells carried out in TG/DTA7200, Hitachi, Japan model equipment. The shells’ ash chemical composition was first time determined by the X-ray diffractions powder, that it consists of significantly higher 40% these chemical elements including manganese, nickel, little zinc, sulfur, aluminum, phosphorus, iron, magnesium, and calcium. The solubility of purified pyrolysis tar of shells in hexane, benzene and dichloromethane were investigated by using silicagel column and the chemical composition of each fraction determined by using of GC/MS chromatography system. The FTIR spectra of shell and pyrolysis tar determined by using of a Nicolet 20-PC spectrometer. The porosity structure of activated pyrolysis hard residue determined by the SEM analysis.


2014 ◽  
Vol 11 (19) ◽  
pp. 5581-5594 ◽  
Author(s):  
K. Desboeufs ◽  
N. Leblond ◽  
T. Wagener ◽  
E. Bon Nguyen ◽  
C. Guieu

Abstract. We report here the elemental composition of sinking particles in sediment traps and in the water column following four artificial dust seeding experiments (each representing a flux of 10 g m−2). Dry or wet dust deposition were simulated during two large mesocosms field campaigns that took place in the coastal water of Corsica (NW Mediterranean Sea) representative of oligotrophic conditions. The dust additions were carried out with fresh or artificially aged dust (i.e., enriched in nitrate and sulfate by mimicking cloud processing) for various biogeochemical conditions, enabling us to test the effect of these parameters on the chemical composition and settling of dust after deposition. The rates and mechanisms of total mass, particulate organic carbon (POC) and chemical elements (Al, Ba, Ca, Co, Cu, Fe, K, Li, Mg, Mn, Mo, N, Nd, P, S, Sr and Ti) transfer from the mesocosm surface to the sediment traps installed at the base of the mesocosms after dust deposition show that (1) 15% of the initial dust mass was dissolved in the water column in the first 24 h after seeding. Except for Ca, S and N, the elemental composition of dust particles was constant during their settling, showing the relevance of using interelemental ratios, such as Ti/Al as proxy of lithogenic fluxes. (2) Whatever the type of seeding (using fresh dust to simulate dry deposition or artificially aged dust to simulate wet deposition), the particulate phase both in the water column and in the sediment traps was dominated by dust particles. (3) Due to the high Ba content in dust, Ba/Al cannot be used as productivity proxy in the case of high dust input in the sediment traps. Instead, our data suggests that the ratio Co/Al could be a good productivity proxy in this case. (4) After 7 days, between 30 and 68% of added dust was still in suspension in the mesocosms. This difference in the dust settling was directly associated with a difference in POC export, since POC fluxes were highly correlated to dust lithogenic fluxes signifying a ballast effect of dust. The highest fraction of remaining dust in suspension in the mesocosm at the end of the experiment was found inversely correlated to Chl a increase. This suggests that the fertilizing effect of dust on autotrophs organisms, the ballast effect, and POC fluxes are strongly correlated. (5) Our data emphasize a typical mass ratio Lithogenic/POC fluxes around 30 which could be used as reference to estimate the POC export triggered by wet dust deposition event.


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