How increased atmospheric carbon dioxide and ‘The Law of the Minimum’ are contributing to environmental obesity

Abstract

Justus von Liebig observed that one could greatly increase agricultural yields by adding relatively small quantities of nitrogen (N), phosphorus (P) and potassium (K) to soils. This finding led to the most recent agricultural revolution. But because most plants and microbes can be non-homeostatic with respect to their biomass elemental composition, adding nutrients can lead to disproportional increases in some macro-elements in organisms, while micronutrient content decreases. Increased CO2 in the atmosphere is an important driver of climate change, but it is also an important driver of changing biomass content and ecosystem stoichiometry. Increased CO2 has contributed to excess carbon in biomass and ecosystems, a state which could be contributing to changes in metabolism which I liken to metabolic diseases and ‘environmental obesity’. Here I defined environmental obesity as excess C accumulation relative to other elements in the environment. A warming climate is certainly motivation enough for humans to do whatever is necessary to decrease use of fossil fuels. However, increased carbon has detrimental health outcomes through effects on our food in natural and agricultural systems and suggests that CO2 is not ‘just an environmental problem’, but also a human health problem.

Editorial: Freshwater sustainability and aquatic ecology in a fast-changing world

“…A few papers focused on ecological and biogeochemical processes on large scales. Cotner (2019) proposed that increased carbon dioxide in Ecuador-the world's country with the largest number of species per unit area. A regional-scale viewpoint was presented by Biesboer (2019) regarding the wild rice Zizania palustris L. in Minnesota (Northern U.S.A).…”

Human Impacts on Aquatic Ecosystems From the Lens of Ecological Stoichiometry

“…Climate models have systematically shown temperature increase as a major climatic response in the Brazilian territory and biomes (Marengo et al 2010(Marengo et al , 2020 with great consequences to hydrology (Brito et al 2018) and biogeochemical cycling in inland waters (Roland et al 2012). For instance, temperature increase may change organisms' growth rates and affect their chemical composition (i.e., stoichiometric imbalance) and, consequently, can affect ecosystem functions as primary production or decomposition (Cotner 2019). Climate change is affecting ecosystem stoichiometry and ecological processes in several ways.…”

“…Recently, it has been shown that increased N, P, and CO 2 availability may 'dilute' micronutrients in crops with important implications for human health (Medek et al 2017;Myers et al 2014). Increasing CO 2 , as well as N and P (from cultural eutrophication, another global environmental issue discussed below) concentrations, may have a similar effect in aquatic ecosystems (Cotner 2019), a phenomenon referred to as 'environmental obesity'; i.e., higher proportions of C fixed by primary producers (i.e., higher C:nutrient ratios) due to the higher atmospheric CO 2 concentrations with consequences to nutrient recycling and energy flow through the aquatic food web (Van Der Walls et al 2010;Cotner 2019). Moreover, increasing temperatures can directly affect aquatic metabolism (Brown et al 2004) by altering growth rates.…”

Ecological stoichiometry in planktonic communities of inland waters: anthropic influences and spatial gradients

“…Whereas aquatic ecosystems with an excess of N and P typically respond with excess growth, due to the central role of these elements in growth, excesses of trace elements typically result in toxicity. Lately, anthropogenic activities have been increasing the concentration of several of trace elements in surface waters, bringing up consequences for ecosystem services (KAYAMURA; ESPOSITO, 2010;RAI;SINGH, 2020;COTNER, 2019).…”

“…Factors that can determine differences in stoichiometry between marine and continental environments and that also vary with latitude, can determine changes in the stoichiometry of aquatic microorganisms. Water temperature, sunlight, availability of nutrients such as N and P, composition of organic matter and predation by other microorganisms are the most commonly reported regulatory factors of bacterial activity (COTNER;BIDDANDA, 2002;COTNER, 2007;BERGGREN et al, 2010). For example, the higher the temperature and the availability of nutrients, the higher the metabolic rates of bacterioplankton, i.e., bacterial growth and respiration rates (e.g.…”