Monthly Archives: February 2019

Life and the five biological laws. Lessons for global change models and sustainability

In a new study in the journal Ecological complexity authors establish the five laws that rule life, arguing that biology adapts to what is available, recycles material and extracts energy from the environment while evolving to develop structures and functions optimized for their environment. Figure: Pixabay

Life on Earth is the result of evolutionary processes acting on a continuous accumulation of structural and functional information by combination and innovation in the use of matter and endo- (inside the organism) and exosomatic (outside the organism) energy and on discontinuous processes of death and destruction that recycle the materials that form structure, information and energy compounds, such as proteins, DNA and ATP, respectively.

In a new study in the journal Ecological complexity authors define five life laws for these vital processes. These processes cannot exceed natural limits of size and rates because they are constrained by space, matter and energy; biology builds on what is possible within these physicochemical limits

“Learning from the way nature deals with the accumulation of information, the limits of size and the rates at which life can acquire and expend energy and resources for maintenance, growth and competition will help us to model and manage our environmental future and sustainability”, explains Prof. Dennis Baldocchi from University of California, Berkeley.

According to this study, the five most prominent laws pertinent to life and ecology are:

  1. The law of mass conservation (introduced by Lomonosov and Lavoisier)
  2. The first law of thermodynamics: energy cannot be created or destroyed in an isolated system
  3. The second law of thermodynamics, the entropy of any isolated system always increases
  4. Information content is a power of the size of the material store with an exponent larger than one
  5. Basic mechanisms such as natural selection, self-organization and random processes drive evolution, generating the huge complexity of organisms and ecosystems.

“Life has adapted to these ecological laws and physical limits for billions of years, and if we humans want to develop a sustainable world, we would do well to not forget them in our use of space, matter and energy. In the end, we are only another biological species among millions on Earth and are living in a very short period of Earth’s history. We should listen and learn lessons from nature that has had several billion years to evolve and get it as right as possible”, says Prof. Josep Peñuelas from CREAF-CSIC.

Reference: Peñuelas, J., Baldocchi, D. 2019. Life and the five biological laws. Lessons for global change models and sustainability. Ecological Complexity

The bioelements, the elementome and the “biogeochemical niche”

Biogeochemical niches_Elementome_2019
Possible responses of species biogeochemical niches to long-term changes in the abiotic and biotic environmental conditions (possible evolutionary changes in the elementome of species). Authors hypothesize that each species has an optimal function related with its niche traits and thus an optimal content of the distinct bioelements. Figure: Peñuelas, J. et al. Ecology 2019.


Every living creature on Earth is made of atoms of the various bioelements (elements used by living organisms) that are harnessed in the construction of molecules, tissues, organisms and communities, as we know them. The most common bioelements are: hydrogen (H) 59%, oxygen (O) 24%, carbon (C) 11%, nitrogen (N) 4%, phosphorus (P) 1% and sulfur (S) 0.1-1% (percentages of total number of atoms in organisms), but there are other bioelements, normally present in low concentrations such as potassium (K), magnesium (Mg), iron (Fe), calcium (Ca), molybdenum (Mo), manganese (Mn) and zinc (Zn). Organisms need these bioelements in specific quantities and proportions to survive and grow.

Distinct species have different functions and life strategies, and have therefore developed distinct structures and adopted a certain combination of metabolic and physiological processes. Each species is thus also expected to have different requirements for each bioelement andbe characterized by an specific bio-elemental composition.

In a new study published in the journal Ecology authors propose that a “biogeochemical niche” can be associated with the classical ecological niche of each species. Authors show from field data examples that a biogeochemical niche is characterized by a particular elementome defined as the content of all (or at least most) bioelements. “The differences in elementome among species are a function of taxonomy and phylogenetic distance, sympatry (the bioelemental compositions should differ more among coexisting than among non-coexisting species to avoid competitive pressure), and homeostasis with a continuum between high homeostasis/low plasticity and low homeostasis/high plasticity”, explains Prof. Josep Penuelas from CREAF-CSIC Barcelona.

The biogeochemical niche hypothesis proposed in this paper has the advantage relative to other associated theoretical niche hypotheses that it can be easily characterized by actual quantification of a measurable trait: the elementome of a given organism or a community, being potentially applicable across taxa and habitats. The changes in bioelemental availability can determine genotypic selection and therefore have a feedback on ecosystem function and organization.

“Further studies are warranted to discern the ecological and evolutionary processes involved in the biogeochemical niche of all types of individuals, taxa and ecosystems. The changes of bioelements availability and use at long timescales should determine phenotypic selection and therefore also ecosystem function and organization, and, at the end, the evolution of life and the environment”, says Prof. Jordi Sardans from CREAF-CSIC.


Reference: Peñuelas, J., Fernández-Martínez, M., Ciais, P., Jou, D., Piao, S., Obersteiner, M., Vicca, S., Janssens, I.A., Sardans, J. 2019. The bioelements, the elementome and the “biogeochemical niche”. Ecology 2019.

The Physics and Ecology of Mining Carbon Dioxide from the Atmosphere by Ecosystems

Planting trees_Jan 2019_Pixabay Avets_Jan2019_Pixabay_b
Reforesting and managing ecosystems have been proposed as ways to mitigate global warming and offset anthropogenic carbon emissions. Photo by: Pixabay

Natural solutions have been proposed to stop and reverse the steady rise in CO2 in the atmosphere. Theses natural solutions nclude planting a tree in our back yard or buying carbon credits, that finance the planting of millions of trees and restoring ecosystems

In a new study in the journal Global Change Biology authors provide their perspective on how well plants and ecosystems sequester carbon. Their analyses is based on 1163 site-years of direct eddy covariance measurements of gross and net carbon fluxes from 155 sites across the globe. The ability of individual plants and ecosystems to mine carbon dioxide from the atmosphere, as defined by rates and cumulative amounts, are limited by laws of physics and ecological principles. “Consequently, the rates and amount of net carbon uptake are slow and low compared to the rates and amounts of carbon dioxide we release by fossil fuels combustion. Furthermore, managing ecosystems to sequester carbon can also cause unintended consequences to arise”, said Prof. Dennis Baldocchi from University of California, Berkeley.

In this opinion piece, authors articulate a series of key take-home points:

– First, the potential amount of carbon an ecosystem can assimilate on an annual basis scales with absorbed sunlight, which varies with latitude, leaf area index and available water.

– Second, efforts to improve photosynthesis will come with the cost of more respiration.

– Third, the rates and amount of net carbon uptake are relatively slow and low, compared to the rates and amounts and rates of carbon dioxide we release by fossil fuels combustion.

– Fourth, huge amounts of land area for ecosystems will be needed to be an effective carbon sink to mitigate anthropogenic carbon emissions.

– Fifth, the effectiveness of using this land as a carbon sink will depend on its ability to remain as a permanent carbon sink.

– Sixth, converting land to forests or wetlands may have unintended costs that warm the local climate, such a changing albedo and soil moisture, increasing surface roughness or releasing other greenhouse gases.

Authors point out that they do not argue that planting forests and deep-rooted perennial grasslands or restoring peatlands and wetlands should not be part of the climate mitigation portfolio. Prof. Penuelas from CREAF-CSIC Barcelona argues that “Given the urgency of reducing carbon dioxide in the atmosphere, the relatively low potential of converting solar energy to stored carbon, the vast amount of land needed to be significant carbon sinks and the risk for unintended consequences, we want the reader to consider that political capital and resources may be better aimed towards more effective and immediate solutions, like reducing and eliminating carbon emissions that are associated with fossil fuel combustion”.

Reference: Baldocchi, D., Peñuelas, J. 2019. The Physics and Ecology of Mining Carbon Dioxide from the Atmosphere by Ecosystems. Global Change Biology 2019