Plant Cultivation: A Strong and Sustainable Response to CO2 Emissions

Abstract

According to the quantities of plant and animal products placed on the world market in 2022, agriculture and forestry captured 20.1 ± 1.5 billion tonnes (Gt or Pg) of CO2, with a weighted mean duration of the corresponding storage of 10.9 ± 3.3 years. These figures are supplemented here by the unharvested above-ground and below-ground parts of plants that are left in place and increase the soil organic carbon pool. This brings the capture by cultivated whole plants to 41.0 ± 0.6 GtCO2, and the storage duration weighted mean to 26.3 ± 2.0 years in 2022. This was the largest global contribution to the reduction of atmospheric CO2 by amplitude and duration, which bio-remediated the global anthropogenic emissions totally, cancelling their influence on climate. The enrichment of the atmosphere with CO2 comes probably from the ocean, which could be a source and not a sink. Complementary approaches, freed from doctrinal preconceptions, should make it possible to clarify further the compensations of CO2 emissions by plants and their environmental consequences.

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Muller-Feuga, A. (2024) Plant Cultivation: A Strong and Sustainable Response to CO2 Emissions. Journal of Geoscience and Environment Protection, 12, 68-88. doi: 10.4236/gep.2024.1210005.

1. Introduction

Accepting the postulate that carbon dioxide emissions have a negative influence on the Earth’s climate, most governments have taken binding measures to reduce them, especially those resulting from the combustion of fossil fuels. To this end, they have notably established and promoted carbon capture, utilization and storage (CCS or CUSC) systems, mainly by geological burial.

In what follows, we examine the contribution of world agriculture and forestry. To do this, we distinguish between stocks and fluxes, with only the latter, which is the variation of the former, giving rise to carbon exchanges in the form of CO2. Table 1 lists the main global carbon stocks and fluxes as reported in the literature.

Table 1. Main global carbon stocks (GtC or PgC) and fluxes (GtCO2) averaged over the period 2010-2022 and references. The + sign of the flux indicates an increase and sign a decrease of the stock.

Stock

Carbon stocks GtC

Carbon fluxesGtCO2/y

References Stock - Flux

Limestone rocks

140.000.000

+3.2 × 10−5

(Sorokhtin et al., 2007) - (Vinos, 2022)

Inorganic ocean

39.000

+10.3

(Friedlingstein et al., 2023) - ibid.

Soils and permafrost

3.100

0.0

(Canadell et al., 2021) - ibid.

Hydrocarbons

905

−40.0

(Canadell et al., 2021) - ibid.

Atmosphere

885

+18.7

(Canadell et al., 2021) - ibid.

Organic ocean

703

0.0

(Friedlingstein et al., 2023) - ibid.

Continental vegetation

450

+12.5

(Canadell et al., 2021) - ibid.

Geological CCS

0.07

+0.7

(Global CCS Institute. 2023)- ibid.

Total

140.045.000

+2.2

Limestone rocks are the main carbon reservoirs on the planet. Their formation and that of hydrocarbons were to the detriment of the atmosphere, which went from 7.000 to 420 ppmv in 600 million years (Godwin, 2022). This depletion is worrying because photosynthesis no longer works at low concentrations (Dippers et al., 1995). This is why Muller-Feuga (2024) recommended preferring CCS by plants to geological CCS, which is irreversible. In this article, the statement was made of the underestimation of carbon capture and storage by plants by most of the articles cited by the Intergovernmental Panel of Climate Change (IPCC). Table 1 illustrates this since continental vegetation is only credited with 12.5 ± 3.3 GtCO2/year biofixed from atmosphere, when previous author estimated it at 21 GtCO2/year based on marketed products only.

One of the arguments put forward to justify this underestimation is the rapid return of carbon to the atmosphere due to a short duration of carbon storage of agricultural products. Considering this time the contribution of the non-commercial parts of the cultivated plants left on site, the approach of their capture amount and their storage duration was attempted in what follows. Only 2022 is being considered as the disruptions caused by the COVID-19 pandemic are being resolved.

2. Material and Method

The stoichiometry of the polymerization-mineralization reaction of carbon by photosynthesis and respiration predicts that the production of one ton of dry plant biomass (dm), consisting mainly of hexoses, requires 0.40 tons of carbon (C/dm = 0.40) from 1.47 tons of CO2 (CO2/dm = 1.47) captured in the atmosphere. The C/dm ratio was 0.25 for animal products, 0.50 for wood, 0.52 for ethanol, and 0.96 for sunflower oil. To calculate the amount of CO2 mobilized by a biomass, it is necessary to remove the water that enters for 0% to 94% of the fresh weight, then apply the C/dm factor to the anhydrous weight to obtain the incorporated carbon, or the CO2/dm factor to obtain the CO2 captured in the atmosphere.

The emerged lands are cultivated to cover the needs of humanity and its livestock in food plants (cereals, vegetables, fruits, etc.), textiles (cotton, flax, hemp, etc.), pleasure plants (tobacco, grapes, flowers, etc.), heating and construction. Here, we considered the productions of agriculture and forestry that are fully and precisely reported by FAO statistics at the global level. These plant products capture and store atmospheric carbon modulated by solar energy. The carbon is stored there during the few months to a few centuries that separate the harvest from the mineralization by digestion or combustion, marking the return of carbon to the atmosphere in the form of CO2.

The carbon storage period in agricultural and forestry products is divided between the period of capture by photosynthesis (CP) and the period of restitution by mineralization (RM). During the former period (CP), which separates the beginning of plant growth, by sowing, planting, or previous harvest (n − 1) and the harvest (n), the carbon pool is gradually formed by photosynthetic capture of CO2 from atmosphere. This period lasts between a few months for annual plants and a few decades for trees. As the growth of fruits and vegetables generally presents an S shape (e.g. Tijero et al., 2021), the quantity of carbon captured over time was assumed to be distributed according to an increasing normal distribution law.

The latter period (RM) separates the harvest from mineralization by respiration or combustion with restitution of carbon to the atmosphere under the form of CO2. During this period, organic matter is stored on shelves, in bulk, or in the soil. This period lasts between a few days for perishable fruits and vegetables and a few centuries for lumber and soils. The quantity of carbon released is assumed to be distributed over time according to a decreasing normal distribution law.

Intermediate storage in a hopper, silo or refrigerated room, during which the product is processed and packaged, sometimes precedes marketing. This intermediate storage is as short as possible to increase the economic profitability and will not be considered. The quantities of carbon mobilized in the increase of animal populations are also approached in what follows as well as their storage duration.

Since the normal distribution laws are centered, the mean and median carbon storage durations (CSD) are equal to the sum of half the maximum growth period (CP/2) and half the maximum restitution period (RM/2) according to formula (1).

CSD = (CP + RM)/2 (1)

The equations of the cumulative normal distribution of carbon stock with time S(t) are:

S( t )= Sn/2 ( 1±erf( ( tn+d/2 )/ σ/ 2 ) ) (2)

where

  • t is the time in years,

  • n is the harvest year,

  • Sn is the carbon stock in harvest year n,

  • erf is the error function of the centered normal distribution,

  • d is the duration of the considered period (mean),

  • σ is the camber of the curve (standard deviation).

If t ≤ n, then d is the capture period CP and the erf function is added. If t > n, then d is the restitution period RM and the erf function is subtracted. Figure 1 illustrates the variations of the S(t) functions in a typical case according to Equations (2).

Figure 1. Theoretical variation of carbon stock expressed in % during capture by photosynthesis (CP) and restitution by mineralization (RM), and carbon storage duration (CSD).

To calculate the quantities of CO2 stored and the duration of storage, some assumptions were made regarding water contents, protein contents, the ratio C/dm, durations of CP and RM periods, based on the most relevant data from the literature. The anhydrous weights of each biomass are determined by applying a water content to the fresh weight provided by the statistics. The CP and RM durations are assigned to each biomass, then the mean weighted by anhydrous weights are calculated for each group of biomasses. The dispersion of the results is expressed by their standard deviation. Five groups of biomasses are distinguished in a first time, then three in a second time. In each group of biomasses, our approach distinguishes the commercial products, the aerial parts and the underground parts whose sum constitutes the whole plants.

3. Results

3.1. Agricultural Plant Products

We used FAO statistics under the heading “Production”, then “Crops and animal products” which specify the quantities of plant products marketed by world agriculture in 2022. To determine the carbon capture of these plant products, the anhydrous weights (dm) are obtained by multiplying the fresh weight by 1 minus the water content (dm = fresh weight * (1 - wc)). These water contents (wc) are between less than 10% for seeds and dried fruits and more than 90% for fresh fruits and vegetables.

The consumption of food products ranges from purchase on the market to the use-by date which is generally well-informed and considers storage by refrigeration and freezing which significantly extends it. For most plants, CP is in the order of a year, while RM varies with the water content of the products between a few months and a few decades. Some seeds retain their germination power for several centuries. Appendix 1 shows the global production of the 160 agricultural commodities listed by FAO. The mean CSD weighted by anhydrous products of world agricultural crops in 2022 is 9.1 ± 0.3 years, according to formula (1).

3.2. Fodder

The quantities of meat, milks and eggs consumable by humans expressed in tonnes are described in the FAO statistics “Production - Quantity” and “Primary Livestock”. These products are mainly intended to supplement human food with quality proteins and a set of micronutrients and mineral salts. They result from the conversion by animals, mainly ruminants and monogastrics, of plants from meadows, foliage and crops.

According to Mottet et al. (2017), global livestock consumed 6 Gt/year of anhydrous fodder. The feed conversion rate, given the weight of anhydrous fodder per weight of animal protein, would be 80 for all species combined, according to these authors. A portion of fodder is included in the previous section of agricultural plant products. Still according to Mottet et al. (2017), 14% of the tonnage consumed by global livestock is consumable by humans, A reduction of the same amount is applied to anhydrous fodder so as not to count twice this part consumable by humans.

Appendix 2 shows the 48 global livestock products listed by the FAO. The protein levels used vary between 3.2% for milk and 32% for meat products. Anhydrous fodder is calculated by applying the conversion rate of Mottet et al. (2017). Anhydrous fodder of non-food or protein-free products such as fats, skins, waxes, honey are calculated by applying the conversion rate (dry weight of fodder/fresh weight of livestock product) obtained with protein products, i.e. 4.2.

Fodder is produced and stored for 0.8 to 3 years to await maturity and pass unproductive periods. The RM period of livestock products lasts between 40 days (eggs) and 100 years (beeswax). The mean CSD weighted by the anhydrous weights of fodder from global livestock farms is 1.2 ± 0.1 years, in accordance with formula (1), in 2022.

3.3. Forestry

Statistics on the quantities of wood produced in the world are available in the “Forests” section of “Data” from FAO. These “Production - Quantity” of firewood, saw logs. pulpwood and industrial wood are expressed in cubic meters to be converted into anhydrous tonnes by applying a density varying between 0.49 and 0.70 depending on the nature of the wood.

Appendix 3 shows the 8 global forestry productions in 2022 and the durations of the CP and RM periods. Only the felling of standing trees was considered, excluding products made using the wood from these felling’s to avoid counting them twice. The plant growth period (CP) is between 25 and 50 years. The restitution by mineralization period (RM) varies between 2 years for firewood and 3 centuries for construction timber. The mean CSD weighted by anhydrous products of global forestry calculated according to formula (1) is 31.0 ± 2.7 years in 2022.

3.4. Other Captures

Appendix 4 shows global aquaculture and fisheries products as provided for 2021 by FAO FishStatJ data. Their mean weighted CSD calculated according to formula (1) was 1.6 ± 1.0 years. These productions are an order of 10 lower than the previous ones.

A portion of the carbon in plant products does not return to the atmosphere. It remains part of the animal biomasses, livestock and humanity that feed on it and contribute to the weight increase described in Appendix 5. The mean weighted CSD is 9.5 ± 0.7 years.

4. Discussion

4.1. Commercial Products

Table 2 summarizes the calculation elements depicted in Appendix 1 to 5. Considering only the commercial products, the main global contributions to atmospheric carbon capture by photosynthesis were agriculture (forages and crops) and forestry in 2022.

Table 2. Dry weights of world commercial products of cultivated plants from agriculture and forestry, fisheries and aquaculture and mobilized by the increase in animal populations (FAO, n.d.), CO2/dm ratios, CO2 captures, and mean durations of carbon storage weighted by dry weights, in 2022.

Carbon capture

Dry weights (dm) Gt/y

CO2/dm

CaptureGtCO2/y

CP/2y

RM/2y

CSDy

Fodder

5.44 ± 0.3

1.47

8.0 ± 0.4

0.8

0.4

1.2 ± 0.1

Crops

5.17 ± 0.1

1.47

7.6 ± 0.2

0.4

8.6

9.1 ± 0.3

Forestry

2.49 ± 0.4

1.83

4.6 ± 0.7

18.8

12.2

31.0 ± 0.3

Aquatic products

0.05 ± 0.02

1.10

0.1 ± 0,03

1.4

0.3

1.6 ± 1.0

Animal populations increase

0.02 ± 0.01

0.93

0.02 ± 0.01

0.0

9.5

9.5 ± 0.7

Total

13.16 ± 0.2

20.1 ± 0.3

4.0

5.9

9.9 ± 0.2

Storage durations (CSD) of commercial products are derived from the analysis of FAO statistics to which CP and RM durations were assigned, ranging from a few days for fresh vegetables to 300 years for construction timber. The mean CSD weighted by anhydrous commercial productions of agriculture and forestry was 9.9 ± 0.2 years in 2022. The minor captures (Appendix 4 and 5) were below the precision of the calculation and not considered further.

4.2. Whole Plants

The figures in Table 2 do not include non-commercial plant biomass such as leaves and stems for the aerial part, and roots and exudates for the buried part. These non-commercial aerial and buried parts most often remain on site and enrich the soil with organic carbon.

Unlike the commercial parts, the above and below-ground parts of crops are not included in statistics, having no commercial value. The former part was subject of evaluation in what follows using the harvest index HI, which is the ratio of biomass of the commercial part harvested to the aerial part of the whole plant. This index is on average 0.42 (Hay, 1995) for the three main crops (maize, wheat, rice) which alone provide half of the world’s agricultural production (see Appendix 1). The 157 other crops listed by the FAO have HIs which vary with the cultivar and the climate-edaphic conditions in such proportions that an average is difficult to determine. This other half of world production would merit an in-depth examination species by species. However, if we assume that the same average HI is applicable to this other half, the total capture of aerial parts of global crops would have been in this case 12.1 ± 0.3 GtCO2/year (Table 3). For the products of forestry, we took an HI of 0.8.

Table 3. Means of CO2 captures, weighted by anhydrous productions of global agricultural and forestry, by non-commercial parts, and whole plants in 2022.

Carbon capture

Above ground parts GtCO2/y

Below ground partsGtCO2/y

Whole plantsGtCO2/y

Crops

11.0 ± 0.6

2.8 ± 1.2

21.3 ± 0.4

Fodders

0.0

5.2 ± 1.7

13.2 ± 1.2

Forestry

1.2 ± 0.4

0.8 ± 0.3

6.6 ± 0.03

Total

12.1 ± 0.3

8.8 ± 0.7

41.0 ± 0.6

The below-ground parts are more difficult to assess as they are invisible and rarely quantified. According to Blume et al. (2015), the root system represents 10% to 20% of the total biomass of a tree, 10% to 50% of the biomass of cultivated plants and 50% to 80% of grassland plants. The aerial parts of fodder are counted among the commercial products. The return to the soil in the form of excrement was neglected, minimizing the estimate. Under these conditions, Table 3 shows the distribution of CO2 capture and storage in the two non-commercial parts of cultivated terrestrial plants, and the sum of the commercial and non-commercial parts (whole plants).

According to this calculation, capture by whole plants have reached 41.0 ± 0.6 GtCO2 in 2022, which is twice that of commercial products alone. This figure is an understatement because it does not include the share of non-commercially exploited plant covers, whose contribution is still to specify. Unexploited continental vegetation is stable and plays a marginal role in capturing atmospheric carbon. Should unmanaged forests still capture carbon, they do so at levels much lower than most crops, which FAO mean double yield weighted by dry weights of the products is set at 19.5 ± 0.7 tCO2/ha/y. For example, current logging regulations in Brazil adopt a standard post-harvesting recovery rate of 0.86 m3/ha/y (Vidal et al., 2020), which captures 0.9 tCO2/ha/y. It should be noted here that, contrary to popular belief, forest cutting and burning do not result in a loss of capacity to store and capture CO2. The soil stock remains in place while spontaneous or replanted regrowth continues to capture to ensure tree growth before new cuttings 25 to 35 years later. If the forest is replaced by pastures or crops, the space it frees up captures CO2 at much higher levels.

The capture we obtained represented 1.3% of total atmospheric CO2, 3.2 times the continental sink of Friedlingstein et al. (2022) at 12.8 ± 3.3 GtCO2/y, and 2.1 times that of Pan et al. (2024) at 19.8 GtCO2/y. It also represented four times the oceanic sink estimated by Fay et al. (2023) at 10.3 ± 0.4 GtCO2/y. Above all, it compensated the total anthropogenic emissions estimated at 41.46 GtCO2 in 2022, including 37.15 GtCO2 by energy and industrial combustion of fossil hydrocarbons (Ritchie & Roser, 2024; data from Global Carbon Budget). The difference between these last figures is attributed to non-fossil emissions by mineralization of plant products and by consumption of fossil products other than energy, especially for fertilizers. Even if we attribute all those additional emissions (4.3 GtCO2, Land Use Change) to plant cultivation, its net balance will remain largely positive with 36.7 GtCO2/y removed from the atmosphere.

Our figure was significantly higher than those cited by the IPCC according to which the continental sink would be between 10 and 20 GtCO2/y (Amthor & Baldocchi, 2001; Beer et al., 2010; Ciais et al., 2013; Dusenge et al., 2018; Friedlingstein et al., 2023), and we have tried to understand why such a difference. The figures cited by the IPCC are constructed from field surveys describing carbon fluxes per unit of surface area and time, then extended to the global surfaces of the different plant covers by dynamic models. These covers are forests (tropical, temperate, boreal), tundras, Mediterranean scrubs, crops, savannas, tropical pastures, temperate pastures, and deserts. The surface capture is between 3.7 (deserts) and 43.1 (tropical forest) tCO2/ha/y (Saugier et al., 2001). The share of forests was greatly overestimated, while that of crops, credited with only 10.1 tCO2/ha/year, was significantly less than the FAO mean crop yield seen above. The capture of old-growth unexploited forests was subject to debate revealing the difficulty of its evaluation (Luyssaert et al., 2008; Gundersen et al., 2021; Luyssaert et al., 2021).

The difference between our approach, relying on the chemical composition of the marketed products described by FAO statistics, and that of the authors cited by the IPCC, based on field measures of carbon fluxes extended to cover surfaces, resulted in a four times lower capture of the latter. It seems that this approach comes up against problems of representativeness of the sampling of each plant cover, which surface was defined by satellite remote sensing. In our case, the sampling is extended to all commercialized plants, to which should be added the share of unexploited plants if significant.

4.3. Storage Duration

The soil carbon pool is made up of the non-commercialized aerial parts remaining on site and the below-ground parts after harvest. The CSD of these necromasses correspond to the average residence time of carbon before mineralization by decomposing organisms, erosion and leaching. An annual crop cycle benefits from the carbon stocks already present in the soils which are partly consumed. The additional storage of successive annual cycles makes it possible to stabilize the carbon pool towards an equilibrium. It is this equilibrium that we have tried to render by choosing the retention times from the literature. For forests, the retention times varied between 0.9 and 152 years (Wang et al., 2017). They increased with latitude (x4) and decreased with temperature (x10) and precipitation (x4). Temperate regions achieve a compromise between high and low latitudes. Also, an average residence time of 40 years (Balesdent & Recous, 1997; Pellerin et al., 2019) for the soils of crops and meadows, and of 75 years for those of exploited forests were retained (Table 4). Assuming a normal distribution of mineralization over time, these durations were divided by 2, in accordance with formula (1).

Table 4. Carbon storage durations during photosynthetic capture (CP), during restitution by mineralization (RM), and total carbon storage duration (CSD) for whole plants (means weighted by anhydrous weights of products).

Carbon capture

CP/2y

RM/2y

CSD whole plantsy

Fodders

0.8 ± 1.0

20.0 ± 1.0

20.8 ± 1.0

Crops

0.4 ± 0.6

20.0 ± 0.6

20.4 ± 0.6

Forestry

18.8 ± 4.9

37.5 ± 4.9

56.3 ± 4.9

Weighted mean

3.5 ± 1.6

22.8 ± 2.4

26.3 ± 2.0

Since the capture duration CP cannot be shorter for whole plants than for commercial products, we have taken the same duration as the latter in the following.

Figure 2 shows how were distributed over time the atmospheric CO2 absorption and restitution by products and whole plants of agriculture and forestry harvested in 2022 according to Equation (2) and their argument values depicted in Table 5.

Figure 2. Variations over time of CO2 captured and then released by cultivated whole plants (solid line, red) and their commercial products (dotted line, blue) harvested in 2022 (GtCO2/year).

Table 5. Argument values of Equations (2) illustrated by Figure 2 for harvest year 2022 (n = 2022).

Argument

Notation

Commercial parts

Whole plants

t ≤ n

t > n

t ≤ n

t > n

CO2 captured (GtCO2/y)

Sn

20.12

20.12

41.02

41.02

Cambers

σ

0.8

2.0

1.4

6.5

CP/2, RM/2 (y)

d

4.73

6.18

4,73

22.80

Should all the years after 2022 be identical to it, then successive carbon captures and storages would constitute a stock of 294 GtC by biofixation of 1.078 GtCO2 from atmosphere (or CSD times the whole plant capture of 2022 harvest), in addition to the pre-existing one, after 26.3 years (or CSD years) and which remains at this level thereafter. This is of the order of magnitude of the stocks of continental vegetation alone, without those of soils and permafrosts, of Canadell et al., 2021, (see Table 1). By going back further into the last century, it would be possible to quantify the carbon stocks of whole cultivated plants that have been built up since then.

5. Conclusion

Here, we attempt to clarify the contribution of cultivated whole plants to the consumption of atmospheric CO2 with a margin of uncertainty relating to both quantities stored and retention times. When some doubts arose, we retained the hypotheses minimizing both. This is a delicate exercise due to the diversity of the factors involved, which were chosen in the literature among the most relevant. Subject to the accuracy and completeness of those factors and of the FAO statistics, capture by plant and animal products placed on the market represented 20.1 ± 1.5 GtCO2 in 2022. Taking into additional account the biomass left on site during these productions brings this capture to 41.0 ± 0.6 GtCO2/year, which significantly increased the contribution of cultivated plants. These figures need to be refined and completed by their evolution in time and space, but they describe major trends. They reveal the outstanding contribution of agriculture and forestry, which is not considered at its fair value, their share being systematically minimized when not presented as net emitting. These activities mobilize atmospheric CO2 at levels that make them by far the main carbon capture and storage system in the hands of Man, without him having to change his practices to achieve this result. In addition, they allow the return to the atmosphere of this gas crucial for the planetary ecosystem, unlike geological CCS.

Therefore, it is not the anthropogenic fossil emissions that are responsible for the increase in atmospheric CO2 since they were entirely bio-remediated by the capture of cultivated plants. This calls into question their much-criticized influence on climate change and destroys the foundations of the emission reduction politics conducted by international organizations et retained by governments.

Then what are the real sources responsible for atmospheric CO2 increase by 18.7 GtCO2/year (2.5 ppm/year)? To provide such quantities, the only other possible source is the ocean, which would not be a sink, as presented in many works, but a source. We had highlighted the seasonal versatility of the ocean, and its sink-source alternation linked to oscillations in atmospheric CO2 content as measured at Mount Mauna Loa (Muller-Feuga, 2023). Ocean degassing is reportedly underway.

It also follows from our calculation that the mean duration of carbon storage by cultivated plants, estimated at more than a quarter of a century, is substantial and greater than expected. With such large captures and such long storage times, the lack of attention paid to agriculture and forestry by international bodies and governments is not explicable. These ancestral activities that feed, warm, delight and clothe Man are based on photosynthesis to which we owe life, and which remains the simplest and most effective means of capturing and storing atmospheric CO2.

Acknowledgements

We thank the many people involved in collecting and providing the global data and recognize the significant resources, people and time, that go into collecting this invaluable data. We do not forget to thank the engineers who wrote the programs for processing this data, putting them online, and making them easily available to us as users.

Appendix 1. Crops

World plant productions from agriculture in 2022 (FAO, n.d.), capture-photosynthetic period (CP) duration, restitution by mineralization period (RM) duration of crops products and share of total production, sorted by decreasing dry weight. Water contents are taken from several sources including https://feedtables.com and https://www.lanutrition.fr.

Product

Fresh weigth (tonnes)

Water content %

Dry weight (Mt)

CP (y)

RM (y)

Share%

Maize (corn)

1,163,497,383

13.7

1004.1

0.8

20

19.4

Wheat

808,441,568

13.1

702.5

0.8

20

13.6

Rice

776,461,457

12

683.3

0.8

20

13.2

Sugar cane

1,922,059,851

70

576.6

1.0

40

11.2

Oil palm fruit

424,587,460

0.1

424.2

0.8

5

8.2

Soya beans

348,856,427

10.5

312.2

0.8

10

6

Barley

154,877,140

12.8

135.1

0.8

20

2.6

Cassava. fresh

330,408,754

59.7

133.2

0.8

0.5

2.6

Potatoes

374,777,763

78.3

81.3

1.0

0.5

1.6

Rape or colza seed

87,221,221

12

76.8

0.8

20

1.5

Other vegetables. fresh n.e.c.

297,995,825

75

74.5

0.8

0

1.4

Seed cotton. unginned

69,668,143

8

64.1

0.8

20

1.2

Sorghum

57,581,943

12.2

50.6

0.8

20

1

Sunflower seed

54,285,949

7.2

50.4

0.8

20

1

Groundnuts, excluding shelled

54,238,560

12

47.7

0.8

1

0.9

Sugar beet

260,998,614

83.9

42

0.8

40

0.8

Coconuts, in shell

62,409,431

45

34.3

1.0

10

0.7

Bananas

135,112,326

75.8

32.7

0.8

0.3

0.6

Millet

30,859,664

10.4

27.7

0.8

0.5

0.5

Beans, dry

28,346,199

10.1

25.5

0.8

10

0.5

Oats

26,385,330

12.4

23.1

0.8

20

0.4

Tea leaves

29,760,668

25

22.3

0.8

5

0.4

Yams

88,257,159

75

22.1

0.8

0.1

0.4

Other beans, green

23,340,916

11.1

20.8

0.8

0

0.4

Sweet potatoes

86,410,355

78.3

18.8

0.8

1

0.4

Chillies and peppers, green (Capsicum spp. and Pimenta spp.)

36,972,494

50

18.5

0.8

0.2

0.4

Peas, green

20,945,189

12.8

18.3

0.8

0.1

0.4

Onions and shallots, dry (excluding dehydrated)

110,616,270

83.9

17.8

0.8

5

0.3

Chick peas, dry

18,095,248

12.7

15.8

0.8

20

0.3

Eggplants (aubergines)

59,312,600

75

14.8

0.8

0

0.3

Plantains and cooking bananas

44,150,813

67

14.6

0.8

1

0.3

Apples

95,835,965

85

14.4

1.0

0.5

0.3

Grapes

74,942,573

81

14.2

1.0

0

0.3

Peas, dry

14,166,030

12

12.5

0.8

20

0.2

Triticale

14,157,881

13.2

12.3

0.8

20

0.2

Natural rubber in primary forms

15,125,393

20

12.1

0.8

5

0.2

Mushrooms and truffles

48,335,996

75

12.1

1.0

0

0.2

Rye

13,143,055

12

11.6

0.8

20

0.2

Tomatoes

186,107,972

94

11.2

0.8

0

0.2

Olives

21,449,868

50

10.7

1.0

5

0.2

Carrots and turnips

42,233,350

75

10.6

0.8

0.2

0.2

Mangoes, guavas and mangosteens

59,151,823

83

10.1

1.0

0.1

0.2

Watermelons

99,957,595

90

10

0.8

0.1

0.2

Other fruits, n.e.c.

38,200,106

75

9.6

1.0

0.1

0.2

Cucumbers and gherkins

94,718,397

90

9.5

0.8

0

0.2

Coffee, green

10,782,334

20

8.6

0.8

0.2

0.2

Cow peas, dry

9,774,866

12

8.6

0.8

20

0.2

Spinach

33,116,288

75

8.3

0.8

0

0.2

Oranges

76,410,037

90

7.6

1.0

0.1

0.1

Cereals n.e.c.

8,713,290

13.2

7.6

0.8

20

0.1

Pineapples

29,361,138

75

7.3

0.8

0

0.1

Green garlic

29,149,438

75

7.3

0.8

0.1

0.1

Other tropical fruits, n.e.c.

28,359,402

75

7.1

0.8

0.1

0.1

Lettuce and chicory

27,149,446

75

6.8

0.8

0

0.1

Sesame seed

6,741,479

12

5.9

0.8

20

0.1

Lentils, dry

6,655,828

11.6

5.9

0.8

20

0.1

Broad beans and horse beans, dry

6,144,395

12

5.4

0.8

20

0.1

Cocoa beans

5,874,582

12

5.2

0.8

0.2

0.1

Cabbages

72,603,755

93

5.1

0.8

0

0.1

Dates

9,747,570

50

4.9

0.8

0.1

0.1

Pigeon peas, dry

5,326,932

12

4.7

0.8

20

0.1

Taro

17,718,129

75

4.4

0.8

0.5

0.1

Tangerines, mandarins, clementines

44,179,831

90

4.4

1.0

0

0.1

Other pulses n.e.c.

4,904,918

12

4.3

0.8

0

0.1

Pears

26,324,874

84

4.2

1.0

0.5

0.1

Chillies and peppers, dry (Capsicum spp., Pimenta spp.), raw

4,909,321

25

3.7

0.8

1

0.1

Linseed

3,973,932

8

3.7

0.8

20

0.1

Walnuts, in shell

3,874,025

12

3.4

1.0

0.5

0.1

Cashew nuts, in shell

3,852,868

12

3.4

0.8

0.5

0.1

Almonds, in shell

3,630,428

12

3.2

1.0

0.5

0.1

Jute, raw or retted

3,503,448

12

3.1

0.8

20

0.1

Cantaloupes and other melons

28,558,069

90

2.9

1.0

0

0.1

Okra

11,232,656

75

2.8

0.8

0.2

0.1

Peaches and nectarines

26,354,497

90

2.6

1.0

0.1

0.1

Plums and sloes

12,391,467

80

2.5

1.0

0

0

Green corn (maize)

9,868,461

75

2.5

1.0

0.5

0

Other stimulant, spice and aromatic crops, n.e.c.

3,172,095

25

2.4

0.8

1

0

Unmanufactured tobacco

5,780,940

60

2.3

1.0

5

0

Pumpkins, squash and gourds

22,806,321

90

2.3

0.8

0

0

Avocados

8,978,275

75

2.2

1.0

0

0

Areca nuts

2,542,072

12

2.2

0.8

1

0

Edible roots and tubers with high starch or inulin content, n.e.c., fresh

8,877,780

75

2.2

0.8

0.2

0

Asparagus

8,824,150

75

2.2

1.0

0

0

Lemons and limes

21,529,604

90

2.2

1.0

0.2

0

Anise, badian, coriander, cumin, caraway, fennel and juniper berries, raw

2,751,010

25

2.1

0.8

0.5

0

Other oil seeds, n.e.c.

2,527,518

20

2

0.8

0.5

0

Buckwheat

2,235,193

12

2

1.0

20

0

Mixed grain

2,223,144

12

2

0.8

20

0

Cauliflowers and broccoli

26,058,228

93

1.8

0.8

0

0

Coir, raw

1,939,430

12

1.7

0.8

20

0

Castor oil seeds

1,829,522

12

1.6

0.8

20

0

Chestnuts, in shell

2,131,241

25

1.6

1.0

1

0

Papayas

13,822,328

89.4

1.5

1.0

0.1

0

Other citrus fruit, n.e.c.

14,422,194

90

1.4

1.0

0.1

0

Onions and shallots, green

4,970,615

75

1.2

0.8

0.1

0

Lupins

1,644,691

25

1.2

0.8

0.1

0

Broad beans and horse beans, green

1,642,153

25

1.2

0.8

0.2

0

Ginger, raw

4,874,216

75

1.2

0.8

0.2

0

Cashewapple

1,329,862

12

1.2

0.8

20

0

Kiwi fruit

4,539,471

75

1.1

1.0

0.1

0

Pomelos and grapefruits

9,761,755

90

1

1.0

0.1

0

Strawberries

9,569,865

90

1

0.8

0

0

Pistachios, in shell

1,026,803

12

0.9

1.0

20

0

Hazelnuts, in shell

1,195,732

25

0.9

1.0

0.5

0

Persimmons

4,436,475

80

0.9

1.0

0.1

0

Other nuts (excluding wild edible nuts and groundnuts), in shell, n.e.c.

1,051,017

25

0.8

0.8

1

0

Tallowtree seeds

1,038,671

25

0.8

0.8

20

0

Apricots

3,863,180

80

0.8

1.0

0

0

Safflower seed

995,508

25

0.7

0.8

1

0

Melonseed

968,692

25

0.7

0.8

20

0

Pepper (Piper spp.), raw

812,674

12

0.7

0.8

20

0

Maté leaves

1,653,167

60

0.7

1.0

5

0

Mustard seed

852,808

25

0.6

0.8

20

0

Karite nuts (sheanuts)

815,825

25

0.6

0.8

10

0

Fonio

658,708

12

0.6

0.8

10

0

Cherries

2,765,827

80

0.6

0.8

0.1

0

Leeks and other alliaceous vegetables

2,109,066

75

0.5

1.0

0

0

Vetches

684,264

25

0.5

0.8

0.2

0

Artichokes

1,584,514

75

0.4

1.0

0

0

Yautia

396,407

12

0.3

1.0

0

0

Tung nuts

453,685

25

0.3

0.8

1

0

Sour cherries

1,593,025

80

0.3

1.0

0

0

Blueberries

1,228,596

75

0.3

1.0

0.1

0

String beans

1,375,584

80

0.3

0.8

0.1

0

Other berries and fruits of the genus vaccinium n.e.c.

1,021,643

75

0.3

0.8

1

0

Kola nuts

315,024

25

0.2

0.8

20

0

Figs

1,242,449

82

0.2

1.0

0.1

0

Flax, raw or retted

875,995

75

0.2

0.8

20

0

Other sugar crops n.e.c.

872,416

75

0.2

0.8

40

0

Canary seed

245,568

12

0.2

0.8

20

0

Kapok fruit

283,287

25

0.2

0.8

0.2

0

Cinnamon and cinnamon-tree flowers, raw

222,524

12

0.2

0.8

1

0

Currants

764,499

75

0.2

1.0

0

0

Bambara beans, dry

246,511

24

0.2

0.8

20

0

True hemp, raw or retted

247,064

25

0.2

1.0

0.2

0

Quinces

702,015

75

0.2

0.8

0.1

0

Kenaf, and other textile bast fibres, raw or retted

224,926

24

0.2

0.8

20

0

Sisal, raw

213,305

24

0.2

1.0

20

0

Cloves (whole stems), raw

183,452

12

0.2

0.8

20

0

Cranberries

582,924

75

0.1

0.8

1

0

Quinoa

158,985

12

0.1

0.8

10

0

Other fibre crops, raw, n.e.c.

554,146

75

0.1

1.0

0.1

0

Other stone fruits

615,695

80

0.1

0.8

1

0

Nutmeg, mace, cardamoms, raw

138,888

12

0.1

1.0

0.1

0

Hop cones

158,545

24

0.1

0.8

0

0

Carribean sprout

396,407

75

0.1

0.8

0

0

Raspberries

947,852

90

0.1

1.0

0

0

Abaca, manila hemp, raw

107,495

24

0.1

0.8

20

0

Brazil nuts, in shell

79,278

12

0.1

0.8

0.5

0

Agave fibres, raw, n.e.c.

40,639

12

0.04

0.8

20

0

Hempseed

42,267

24

0.03

1.0

20

0

Other pome fruits

129,481

80

0.03

1.0

0.2

0

Chicory roots

32,662

24

0.02

0.8

0.2

0

Gooseberries

95,425

80

0.02

1.0

0

0

Poppy seed

14,857

12

0.01

0.8

1

0

Peppermint, spearmint

51,081

75

0.01

0.8

0

0

Locust beans (carobs)

56,423

80

0.01

1.0

0

0

Vanilla, raw

7704

24

0.01

0.8

1

0

Ramie, raw or retted

7625

24

0.01

0.8

20

0

Pyrethrum, dried flowers

5049

12

0.004

0.8

1

0

Jojoba seeds

147

12

0.0001

0.8

20

0

Total

9609.9

5165.8

100

Appendix 2. Fodder

Anhydrous fodder consumed by global animal production in 2022 (FAO, n.d.) capture-photosynthetic period (CP), restitution by mineralization period (RM) of livestock products and share of total production, sorted by decreasing dry fodder weight. The protein contents were taken from https://www.la-viande.fr/nutrition-sante.

Product

Fresh weight (t)

Protein content %

Dry fodder (Mt)

CP (y)

RM (y)

Share %

Meat of chickens, fresh or chilled

123,631,335

30

1453.9

0.8

0.5

21.1

Meat of pig with the bone, fresh or chilled

122,585,397

30

1441.6

2

0.5

20.9

Raw milk of cattle

753,320,578

3.2

945

1

0.5

13.3

Meat of cattle with the bone, fresh or chilled

69,346,116

32

869.9

3

0.5

11.9

Hen eggs in shell, fresh

86,999,551

12.7

433.1

0.8

0

14.9

Raw milk of buffalo

143,573,178

4.8

267.3

1

0.5

2.5

Meat of sheep, fresh or chilled

10,272,315

30

120.8

2

0.5

1.8

Edible offal of cattle, fresh, chilled or frozen

9,570,874

25

93.8

3

0.5

1.6

Edible offal of pigs, fresh, chilled or frozen

8,013,905

25

78.5

2

0.5

1.4

Meat of buffalo, fresh or chilled

6,903,484

25

67.7

3

0.5

1.2

Meat of goat, fresh or chilled

6,367,497

25

62.4

2

0.5

1.1

Meat of ducks, fresh or chilled

6,068,757

25

59.5

0.8

0.5

1

Fat of pigs

11,125,681

0

47.1

0.8

10

0.8

Meat of turkeys, fresh or chilled

5,081,498

25

49.8

0.8

0.5

0.9

Meat of geese, fresh or chilled

4,418,972

25

43.3

0.8

0.5

0.8

Raw hides and skins of cattle

8,698,960

0

36.8

0.8

10

0.6

Raw milk of goats

19,191,573

4.3

32

1

0.5

0.3

Eggs from other birds in shell, fresh, n.e.c.

6,171,896

12.7

30.7

0.8

0

1.1

Raw milk of sheep

10,093,016

5.8

22.7

1

0.5

0.2

Game meat, fresh, chilled or frozen

2,032,707

25

19.9

2

0.5

0.3

Edible offal of sheep, fresh, chilled or frozen

1,823,000

25

17.9

1

0.5

0.3

Cattle fat, unrendered

3,392,343

0

14.4

0.8

10

0.2

Other meat n.e.c. (excluding mammals), fresh, chilled or frozen

1,563,630

25

15.3

0.8

0.5

0.3

Edible offal of goat, fresh, chilled or frozen

1,260,496

25

12.4

1

0.5

0.2

Edible offal of buffalo, fresh, chilled or frozen

1,173,340

25

11.5

3

0.5

0.2

Raw hides and skins of sheep or lambs

1,981,013

0

8.4

0.8

10

0.1

Natural honey

1,830,768

0

7.7

0.8

100

0.1

Shorn wool, greasy, including fleece-washed shorn wool

1,759,760

0

7.4

0.8

10

0.1

Horse meat, fresh or chilled

775,543

25

7.6

4

0.5

0.1

Meat of rabbits and hares, fresh or chilled

756,476

25

7.4

0.8

0.5

0.1

Raw hides and skins of buffaloes

1,409,455

0

6

0.8

10

0.1

Raw hides and skins of goats or kids

1,267,834

0

5.4

0.8

10

0.1

Meat of camels, fresh or chilled

604,530

25

5.9

3

0.5

0.1

Raw milk of camel

4,116,669

3.4

5.5

1

0.5

0.1

Sheep fat, unrendered

576,409

0

2.4

0.8

10

0

Buffalo fat, unrendered

416,812

0

1.8

0.8

10

0

Silk-worm cocoons suitable for reeling

414,788

0

1.8

0

2

0

Goat fat, unrendered

256,756

0

1.1

0.8

10

0

Meat of asses, fresh or chilled

104,305

25

1

3

0.5

0

Edible offals of horses and other equines, fresh, chilled or frozen

99,085

25

1

3

0.5

0

Edible offals of camels and other camelids, fresh, chilled or frozen

88,365

25

0.9

3

0.5

0

Beeswax

65,063

0

0.3

0

100

0

Meat of other domestic camelids, fresh or chilled

33,135

25

0.3

3

0.5

0

Snails, fresh, chilled, frozen, dried, salted or in brine, except sea snails

20,799

25

0.2

0.8

0.5

0

Meat of other domestic rodents, fresh or chilled

18,701

25

0.2

0.8

0.5

0

Meat of pigeons and other birds n.e.c., fresh, chilled or frozen

18,669

25

0.2

0.8

0.5

0

Fat of camels

27,655

0

0.1

0.8

20

0

Meat of mules, fresh or chilled

13,839

25

0.1

4

0.5

0

Total

1,439,336,530

6319.9

100

Appendix 3. Forestry Products

World forestry anhydrous production in 2022 (FAO, n.d.), capture-photosynthetic period (CP), restitution by mineralization period (RM) of forestry products and share of total production, sorted in order of decreasing dry weight. Densities distinguished non-coniferous and coniferous trees, at 0.7 and 0.49 t/m3 respectively.

Product

Mm3

Density(t/m3)

Dry weight(Mt)

CP (y)

RM (y)

Share%

Wood fuel, non-coniferous

1725

0.70

1208

35

2

48

Sawlogs and veneer logs, coniferous

760

0.49

372

25

30

15

Sawlogs and veneer logs, non-coniferous

382

0.70

268

50

30

11

Pulpwood, round and split, non-coniferous (production)

355

0.70

249

50

30

10

Pulpwood, round and split, coniferous (production)

360

0.49

177

50

30

7

Wood fuel, coniferous

242

0.49

119

25

2

5

Other industrial roundwood, non-coniferous (production)

115

0.70

80

50

300

3

Other industrial roundwood, coniferous (production)

43

0.49

21

25

100

1

Total

3983

2 493

37.6

24.4

100

Appendix 4. Aquatic Products

World anhydrous fisheries and aquaculture production in 2021 (FAO, 2024), capture-photosynthetic period (CP), restitution by mineralization period (RM) of aquatic products and share of total production.

Product

Fresh weight (Mt)

Water content %

Dry weight (Mt)

CP (y)

RM (y)

Share %

Algae

36.34

85

5.5

1

0.5

12

Animals

182.10

78

40.1

3

0.5

88

Total

218

46

2.8

0.5

100

Appendix 5. Increase in Animal Populations

Unlike the previous cases, there is no CP, this having already been included in fodder production. The CSD is equal to the mean longevity weighted by the anhydrous weights of the livestock divided by 2 since it is intended for human consumption. For humanity, the restitution by mineralization period is taken equal to life expectancy at birth, i.e. 72 years according to the World Bank. We divided it by 2 to consider the renewal of the carbon pool during life.

Population increase

Fresh weight (Mt)

Water content %

Dry weight (Mt)

CP (y)

RM (y)

Share %

Livestock (mean 2020-2022)

23.8

73.1

17.4

0.0

10.0

85.5

Humanity (mean 2020-2022)

4.0

73.1

2.9

0.0

72.0

14.5

Total

28

20

0.0

19.0

100

Conflicts of Interest

The authors declare no conflicts of interest regarding the publication of this paper.

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