# Biomass Refined: 99% of Organic Carbon in Soils
## 1 Introduction  
Although this report focuses on Nature's biomass stocks and losses, the issue of increasing biomass energy to replace fossil fuels is also briefly discussed in context of other limitless energy sources, such as terrestrial heat pumps, geothermal energy, and restoration of compressed-air power from falling water in trompe systems or directly from the deeper subterranean. It seems a misguided policy or plan to redirect valuable crop residues or other organic resources from composts that need to be returned to soils, especially if this is under an argument to address the climate issues related to CO\({}_{2}\) increases. With realization that most emissions are from topsoil loss, priority should be the return of carbon directly back to soils in a circular economy, using appropriate organic farm practices. Some data presented herein are well established, others are newly unearthed, but, as always, it is proper and seemly to start revisions at the beginning--from \"the ground up\". Life on Earth is carbon-based, seemingly emerging in geothermal hot-springs on Land, as in [PERSON]'s prescient _\"warm little pond\"_ theory of origin, possibly with Montmorillonite clay catalysis, evidenced by fossil soils claimed to be dated to nearly 4 billion years and living entities on land for \(>\)3.5 billion years [1; 2; 3; 4; 5; 6]. Evolving organisms faced extreme challenges of radiation and resource scarcity that gradually resolved when land plants emerged, spurring the Neoproterozoic Oxygenation Event (NOE) that released sufficient oxygen, O\({}_{2}\), for ozone, O\({}_{3}\), to form, blocking the Sun's harmful UV-B radiation whilst fueling bountiful nutrient turnover in biomass (Figure 1). Atmospheric oxygen (O\({}_{2}\)) increase is stoichiometrically interlinked to carbon dioxide (CO\({}_{2}\)) removal in classic photosynthesis \(\leftrightarrow\) respiration equations, shown simplified here:  
\[\text{CO}_{2}+\text{H}_{2}\text{O}\leftarrow\rightarrow\text{CH}_{2}\text{O}+ \text{O}_{2}\]  
From the left the formula is carbohydrate photosynthesis; in reverse from the right is equal but opposite respiration/decomposition/incination consuming biomass (Figure 2). (Ma) ago, Phanerozoic carbon was mainly sequestered on land; initially in living biomass, accumulating in primal soil organic matter (SOM, e.g., humus or [PERSON]'s _\"vegetable mould\"_), or sometimes fixed in anoxic sediments as peat, coal, oil, and other fossil fuels or non-fuel fossils, with a concurrent and constant recycling on land of vital biomass, then as now. How much carbon was fixed? Increasingly, our understanding is of substantial SOM sequestration, given the much higher early carbon dioxide levels around 550 Ma (Figure 3). As well as primordial Chloroplasts and Mitochondria as endosymbionts, early symbioses--as formed over 400 Ma between fungi and cyanobacteria/algae in the lichens of land's Biocrust--were partnerships between fungi and plants with mycorrhizal fungi emerging as early as 500 Ma [9]. This attests to biotic inter-reliance between taxonomic groups for synergy and survival. Moreover, fungi fruiting above-ground are considered soil-based, as indeed now are most land plants. Related to fungi, particularly arbuscular mycorrhizal (AM) fungi, known previously as vesicular-arbuscular mycorrhiza (i.e., VAM), these are reported to consume up to 50% of the photosynthes from host plants. Such below-ground factors are often overlooked in biomass budgets and productivity models partly through oversight of soil basics and in part because the extent of ancient soil fungal syntheses are relatively recent discoveries. Refs. [10,11] show an estimated 10-50% of the carbon captured by photosynthesis is transferred under-ground to the AM fungi, with earliest fossil symbioses from 250 to 400 million years ago (e.g., [12]). Part of these nutrients are converted into glomalin, discovered only in the 1990s [13], as a fungal hyphae/spore-derived glycoprotein that is tightly bound to soil particles, earning it the epithet of a _\"super glue\"_.