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Get type and amount of residue produced for each crop production item.

Usage

get_primary_residues(
  example = FALSE,
  cereal_residue = c("ipcc", "ensemble", "ratio", "wirsenius"),
  oil_palm_residue = c("per_product", "per_hectare", "pin"),
  non_cereal_residue = c("ipcc", "ensemble", "ratio", "pin")
)

Arguments

example

If TRUE, return a small example output without downloading remote data. Default is FALSE.

cereal_residue

How cereal residue is estimated. One of:

  • "ipcc" (default): the IPCC yield-dependent line, above-ground residue dry matter = slope x grain dry-matter yield + intercept, through calculate_crop_residues() with its modern-variety correction.

  • "ensemble": the same estimator's mean of that line and the static biomass_coefs ratio, as the soil carbon and nitrogen chain uses it.

  • "ratio": the static biomass_coefs ratio alone.

  • "wirsenius": the predecessor's model, Wirsenius (2000) Table 3.16 regional ratios, applied directly on Wirsenius's own region membership.

See the "Cereal residue" section. Other crops are not affected.

oil_palm_residue

How oil palm residue (fronds and trunks) is obtained. One of:

  • "per_product" (default): 60 Mt DM / 83.09 Mt of fresh fruit bunches = 0.722 t DM per tonne of fruit, Malaysia's 2010 fronds and trunks over its 2010 FAOSTAT production. It keeps the pin's production-times-ratio form and is the cautious rule where the per-hectare one is weakest: low-yield, semi-wild palm systems such as Nigeria's (2.6 t of fruit per hectare against Malaysia's ~17), which "per_hectare" would give several times the residue. West African semi-wild systems stay uncertain under either rule and would need their own source. Maintainer decision (whep#1424).

  • "per_hectare": 60 Mt DM / 4.85 Mha = 12.37 t DM per harvested hectare, the same 2010 anchor. It treats frond and trunk production as a property of the standing palm, and the rate barely moves between the strategy's two Malaysian years (12.26 t DM/ha at 2012, from its "over 83 million dry tonnes" times "about 75 percent" on FAOSTAT's 5.08 Mha), where the per-tonne ratio drifts (0.656 at 2012).

  • "pin": the pin's own oil palm residue, with the recovery rate undone and the ratio re-keyed like every other non-cereal crop.

See the "Oil palm residue" section.

non_cereal_residue

How the residue of a non-cereal crop with its own line in IPCC (2006) Table 11.2 is estimated: soybean, groundnut, dry beans, peas, chickpeas, lentils and the other pulses, potato, and, through IPCC's "Tubers" line, cassava, sweet potato, yams and the other roots. One of "ipcc" (default), "ensemble" and "ratio", the same estimators as for cereal_residue, or "pin", the pin's ratio as for every other crop. See the "Non-cereal residue" section.

Value

A tibble with the crop residue data. It contains the following columns:

  • year: The year in which the recorded event occurred.

  • area_code: The code of the country where the data is from. For code details see e.g. add_area_name().

  • item_cbs_code_crop: FAOSTAT internal code for each commodity balance sheet item. This is the crop that is generating the residue.

  • item_cbs_code_residue: FAOSTAT internal code for each commodity balance sheet item. This is the obtained residue. In the commodity balance sheet, this can be three different items right now:

    • 2105: Straw

    • 2106: Other crop residues

    • 2107: Firewood

    These are actually not FAOSTAT defined items, but custom defined by us. When necessary, FAOSTAT codes are extended for our needs.

  • value: The amount of residue produced – all of it, before any is recovered from the field – in tonnes of fresh matter, like every other commodity-balance quantity.

  • value_dm: The same residue in tonnes of dry matter: each crop's fresh residue times its own residue dry-matter content, Residue_kgDM_kgFM in biomass_coefs, summed per row. NA where a crop with residue mass carries no such coefficient, so the gap stays visible rather than reading as zero.

  • method_residue: how the row's residue was estimated: the cereal_residue method for a cereal, the non_cereal_residue method for a non-cereal crop with its own IPCC line, "malaysia_nbs_per_product" or "malaysia_nbs_per_hectare" for oil palm unless oil_palm_residue is "pin", and "pin" for every other crop.

The pin's residue quantities are fresh matter. Across its crops the ratio of pinned residue to product tracks the fresh-matter residue:product ratio kg_residue_kg_product_FM of biomass_coefs (about 0.8 of it for nearly every crop), not the residue's dry-matter content, which runs from 0.13 (tomato) to 1.0 (rapeseed) (whep#1215). Use value_dm wherever a quantity is defined per unit of dry matter, such as a residue nitrogen content.

The pin does not hold the residue produced but the share of it recovered from the field: the predecessor pipeline multiplied each residue row by the legacy recovery rate of its region and crop category (recovery_rates in residue_recovery.csv, see calculate_residue_destinies()) before writing it. Every reader of value treats it as the whole residue and applies a recovery rate of its own, so value is the pin divided by that same rate (whep#1195). The division is exact: WHEP ships the rate the predecessor used, and on the real pin the result equals the predecessor's gross residue on all 427,584 rows where both exist. Where that rate is 0 (fodder crops in seven of the eight regions; roots and tubers, cassava, sugar beet and dry beans in West Europe and in North America and Oceania) the pin holds 0 and the gross residue cannot be recovered from it. Fodder crops and sugar beet carry no residue there, as before; roots and tubers, cassava and dry beans are estimated from yield (see "Non-cereal residue") and so carry the residue they produce, of which the recovery rate of 0 downstream recovers nothing.

The ratio behind the pin's gross residue is the fresh-matter residue:product ratio of biomass_coefs, scaled by the region's residue:product ratio relative to West Europe (residue_dm_product_dm in the same table, Wirsenius (2000) Table 3.16) and by a harvest-index change factor per region and year. That factor is what makes the ratio vary by year. The predecessor's table carries it at eight anchor years from 1910 to 2000, interpolates linearly between them and holds 2000 constant after it, falling for instance from 1.10 in 1962 to 1.00 in 2000 in East Europe. Its code attributes the table to Krausmann et al. (2013), PNAS 110:10324, Table M2 (assumed, unverified), and WHEP does not ship it.

The predecessor looked the regional ratio up by regions_full$region_HANPP, which carries Wirsenius's eight region names but not his membership (Wirsenius 2000, Table 3.1): Southeast Asia, Russia, Belarus, the Caucasus and Sudan took another region's ratio (whep#1430). For every crop that reads the pin, the ratio is re-keyed here on Wirsenius's own membership, through the (HANPP region, UN M49 sub-region) pairs listed in residue_feed_regions.csv. That lowers world non-cereal residue dry matter by 0.2% in 2010.

Cereal residue

Cereals are the one part of the base with a published global series: Smerald, Rahimi & Scheer (2023), A global dataset for the production and usage of cereal residues in the period 1997-2021, Scientific Data 10:685, doi:10.1038/s41597-023-02587-0 , the mean of three methods (constant regional ratios, and two yield-dependent ones). The pin's model put world cereal residue 16.1% above that mean over 1997-2021 (3899 against 3357 Tg dry matter), and 25% above their constant-ratio method in every year with the same grain production (whep#1448). Besides the membership above, two things caused it. The West Europe anchor presumes that biomass_coefs holds the West Europe ratio, and for cereals it does not (wheat 1.34, barley 1.18, sorghum 1.70 and maize 0.96 kg dry matter per kg grain dry matter, against Wirsenius's 1.0, 1.0, 1.2 and 1.2). And Wirsenius's ratios are early-1990s harvest indices, held constant after 2000 while yields rose.

Cereal residue is therefore estimated from the pin's own production and harvested area (its Product rows, which equal the primary_prod pin) with calculate_crop_residues(), the estimator the soil carbon and nitrogen chain already uses. Its modern-variety harvest-index correction applies, keyed on the HANPP region its adoption table is written in. The "ipcc" line is IPCC (2019), 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Vol. 4, Ch. 11, Table 11.2 (p. 11.19), whose cereal slopes and intercepts are those of IPCC (2006) Table 11.2. Measured against Smerald et al. (validation/residue_base_dm.R), world cereal residue in dry matter over 1997-2021 and in 2010 is:

cereal_residue1997-2021 mean, Tgvs Smeraldyears outside band2010, Tg
"ipcc"3385+0.8%0 of 253333
"ensemble"3059-8.9%5 of 253008
"ratio"2732-18.6%25 of 252684
"wirsenius"3656+8.9%9 of 253598
the pin's model3899+16.1%16 of 253826

The band is the spread of Smerald et al.'s three methods, widened by 5%; their 2010 mean is 3334 Tg. "ipcc" matches the world total, but per crop it books maize about 19% and sorghum about 20% below their mean and wheat about 23% above it (2010 and 2020). "wirsenius" keeps the pin's harvest-index factor and corrects the anchor by applying Table 3.16 directly: residue dry matter is grain dry matter times the ratio of the area's Wirsenius region.

Non-cereal residue

The West Europe anchor is not right for non-cereals either, and the error runs both ways (whep#1518). Against the line IPCC (2006) Table 11.2 gives each crop (Vol. 4, Ch. 11, pp. 11.17-11.18), the pin's ratio put world residue dry matter in 2010 at 1.42 times the line for soybean, 1.36 for potato, 1.95 for cassava and 1.88 for sweet potato, but 0.53 for dry beans, 0.41 for the other pulses and 0.34 for chickpeas. Applying Wirsenius (2000) Table 3.16 directly does not cure it: soybean would fall to 0.86 of the line.

So the crops that Table 11.2 gives a line of their own are estimated from the pin's production and harvested area exactly as cereals are, with calculate_crop_residues() and its modern-variety correction:

cropsTable 11.2 rowslopeintercept, t DM/ha
soybeanSoyabean0.931.35
groundnut (with shell)Peanut (w/pod)1.071.54
dry beans, broad beansDry bean0.360.68
peas, chickpeas, lentils, other pulsesBeans & pulses1.130.85
potatoPotato0.101.06
cassava, sweet potato, yams, other rootsTubers0.101.06

The 2019 Refinement's Table 11.2 (updated, p. 11.19) repeats these values. "Tubers" is IPCC's own crop class, "modelled after potatoes"; the crops reach it through ipcc_crop_mapping.csv, as in the soil carbon and nitrogen chain. The other non-cereal lines in ipcc_residue_coefs.csv (rapeseed, sunflower, sugar beet, sugar cane, cotton) are not in Table 11.2, so those crops, tree crops and vegetables keep the pin's ratio, as does every crop under non_cereal_residue = "pin".

World residue dry matter of the crops estimated from yield, Tg, the pin's ratio against "ipcc" (the default):

196120102020
soybean51 -> 63500 -> 385673 -> 494
groundnut33 -> 4890 -> 93112 -> 110
dry beans7 -> 2314 -> 3415 -> 37
peas8 -> 1714 -> 1720 -> 22
other pulses18 -> 5731 -> 7940 -> 97
potato26 -> 3536 -> 2842 -> 27
cassava19 -> 1665 -> 3779 -> 46
sweet potato24 -> 2020 -> 1219 -> 11
all non-cereal residue533 -> 6252159 -> 20702755 -> 2595
all residue2672 -> 27645492 -> 54026622 -> 6462

Soybean, groundnut and potato then sit at 1.05-1.11 of their IPCC line in 2010 and 2020 (validation/residue_base_dm.R): the modern-variety correction and the product dry-matter content of bio_coefs. No published global non-cereal series exists to check them against independently (whep#1399).

Oil palm residue

Oil palm residue is replaced rather than taken from the pin (whep#1424). Read as gross residue, the pin's oil palm residue is far above an oil palm plantation's whole above-ground net primary production, fruit included: 81% of 17.3 Mg C, so about 30 t DM at the 0.47 kg C per kg DM of biomass_coefs, per hectare and year in the industrial plantation of Wakhid, Hirano, Dariah & Agus (2022), Mires and Peat 28:02, doi:10.19189/map.2021.snpg.sta.2288 . In Malaysia it is several times the country's whole solid oil palm biomass, mill residues included.

The anchor is Malaysia's field residue: fronds (46 Mt) and trunks (14 Mt) of dry matter on 4.85 Mha planted in 2010, Exhibit 1 and p. 10 of Agensi Inovasi Malaysia (2013), National Biomass Strategy 2020, version 2.0 (FAOLEX mal228571). Mill residues (empty fruit bunches, fibre, shells) are part of the fruit bunch and are not field residue, so they are left out. The anchor is a gross residue, so it replaces the pin's figure after the recovery rate has been undone and the ratio re-keyed; neither touches it. The anchored dry matter is converted to fresh mass with the oil palm Residue_kgDM_kgFM of biomass_coefs, so value_dm is the anchor exactly. That coefficient is 0.396, the dry matter of fresh oil palm fronds (39.6% as fed, n = 3) in Heuzé, Tran, Sauvant & Lebas (2015), Oil palm fronds and oil palm crop residues, Feedipedia, https://www.feedipedia.org/node/6916 (whep#1516). Fronds are 46 of the 60 Mt; trunks, whose sap is 75-80% of their weight, are wetter, so the fresh mass is if anything understated. It sets the fresh mass booked to Firewood, not the dry matter.

The batch pin on the build path

Two further aliases were published in that same 2025-07-14 batch — crop_residues and bilateral_trade, alongside the four above, between 12:33:43Z and 12:33:50Z. Unlike the four, these two are read on the default build path, which is why no warning is attached to them: every commodity balance build reads them, so a warning at the read is noise rather than information. bilateral_trade has since been regenerated by this package (#1122), so crop_residues is the only one still registered at its 2025-07-14 version.

They did not share a provenance despite sharing a timestamp. Each was established separately (#1054), because the timestamp alone establishes nothing.

crop_residues is predecessor output

Read by get_primary_residues(), and from there by build_commodity_balances(). All 475,688 of its Product rows equal the primary_prod pin's tonnes values exactly — no key unmatched on either side, no value differing at a relative tolerance of 1e-6 — so it is a downstream artifact of the same predecessor run, carrying that run's production series into the commodity balance.

Its residue quantities are those production numbers times a residue-to-product ratio that varies by year, and times a recovery rate: the pin holds the residue the predecessor recovered from the field, not the residue produced (#1195). The predecessor's code (Global/R/crop_npp.r, then afsetools::residue_use()) writes each row as

product * kg_residue_kg_product_FM * HI_changes(region, year) * residue_dm_product_dm(region, category) / residue_dm_product_dm("West Europe", category) * recovery_rates(region, category),

with region and category keyed as in residue_recovery.csv. Rebuilt from the predecessor's own coefficient tables, that formula reproduces all 425,934 pin rows whose region it can key, at a relative tolerance of 1e-6. The year variation is HI_changes alone: a harvest-index change factor per region, given at eight anchor years from 1910 to 2000, linear in between and flat after 2000 (East Europe 1.10 in 1962 to 1.00 in 2000), which the predecessor attributes to Krausmann et al. (2013), PNAS 110:10324, Table M2 (assumed, unverified). It is a regional historical adjustment, not a yield response, and after 2000 the ratio of every region and category is constant. That is why biomass_coefs$kg_residue_kg_product_FM alone reproduces only 3,189 of the 472,790 comparable keys. Of the 33,411 keys that carry a residue of exactly 0, 30,620 are cells whose recovery rate is 0 (fodder crops in seven of the eight regions; roots and tubers, cassava, sugar beet and dry beans in West Europe and in North America and Oceania) and 1,919 are crops whose biomass_coefs ratio is 0.

WHEP ships the recovery rate and the regional ratio the predecessor used (both equal in all 160 cells), but not the HI_changes table. So get_primary_residues() undoes the recovery exactly, dividing by the same rate, but cannot recompute the predecessor's residue from production. It then re-keys the regional ratio on Wirsenius's own region membership, and estimates cereal residue (#1448), and that of the non-cereal crops with their own IPCC Table 11.2 line (#1518), from the pin's production and harvested area instead of reading it.

It is not a small input. The pin holds 7.63 Gt of recovered residue for 2010 (Straw 3.60 Gt, Other crop residues 2.49 Gt, Firewood 1.54 Gt) and 327.7 Gt over 1961–2021, which get_primary_residues() turns into 7.64 Gt (Straw 3.92 Gt, Other crop residues 2.82 Gt, Firewood 0.90 Gt) and 366 Gt of residue produced. 3,998 of its 249,095 output rows carry NA polity columns because the pin is name-keyed.

Driving the same residue model off a fresh get_primary_production() would move those numbers. Measured for 2010 at (area_code, item_prod): 1.958 Gt of current production sits on 6,425 keys the pin never sees (809 Mt of it primary crops, including the modelled temporary-grassland item), 64.8 Mt on 296 keys is pin-only, and of the 8,010 shared keys 538 disagree, putting 1.102 Gt — 11.01% of the pin's shared-key mass — more than 1% apart. The largest class is rice, 673.9 Mt in the pin against 463.3 Mt fresh, a ratio of 0.6876: current code puts rice on a milled-equivalent basis while the pin's is paddy, which is a basis difference rather than an error, since straw scales with the field crop. The second is fodder, where the current build is close to twice the pin on every forage and silage item, the pin predating that work. Replacing the pin therefore means choosing a residue model, which is a science decision and not a refresh. For cereals that model is chosen by get_primary_residues(cereal_residue = ), and for the non-cereals with an IPCC line by non_cereal_residue =; both still run on the pin's production.

bilateral_trade is built by build_detailed_trade()

Read by get_bilateral_trade() and by the live-animal branch of build_commodity_balances(). The registered version, 20261001T135651Z-ca7b3, is build_detailed_trade()'s output verbatim, with its defaults and extend_time = FALSE, run on the faostat-trade-bilateral pin 20260407T095142Z-b3f81 (#1122): 10,038,220 rows over 1986–2021, polity-keyed, carrying 64,450,133,319 tonnes and 87,840,869,640 head.

The 2025-07-14 version it replaces, 20250714T123347Z-2c392, held the same FAOSTAT Detailed Trade Matrix values in the predecessor pipeline's name-keyed schema — against the raw pin over 2010, all 296,642 shared tonnes keys and all 5,102 shared Head keys agree exactly — but without FAOSTAT's 1000 Head rows: 76,141,882 thousand head of live broiler chicken, turkey, duck, rabbit and goose trade over 1986–2021, which PR #1113 recovered in the producer. The regenerated pin carries 7.50x its 11,707,083,640 head and 22.5% less than its 83,147,095,412 tonnes, all of that tonnage difference in CBS items 5001-5003, which no commodity balance carries: item 1293's unbacked tonnage, screened by method_unbacked_quantity (#1023), and three CBS names with no item_cbs_code. On the tonnes that do reach a trade matrix the two versions differ by 0.056%. .clean_bilateral_trade() reads either schema.

Examples

get_primary_residues(example = TRUE)
#> # A tibble: 10 × 11
#>     year area_code polity_area_code reporting_polity_code reporting_polity_name
#>    <dbl>     <dbl>            <int> <chr>                 <chr>                
#>  1  1986       138              138 MEX-1848-2025         Mexico               
#>  2  1979       170              170 PER-1942-2025         Peru                 
#>  3  1963        84               84 GRC-1947-2025         Greece (1947-2025)   
#>  4  2002       138              138 MEX-1848-2025         Mexico               
#>  5  2020       143              143 MAR-1979-2025         Morocco              
#>  6  1991       183              183 ROU-1947-2025         Romania (1947-2025)  
#>  7  2006       131              131 MYS-1965-2025         Malaysia             
#>  8  2002        28               28 MMR-1885-2025         Myanmar              
#>  9  1965        29               29 BDI-1962-2025         Burundi              
#> 10  1966       156              156 NZL-1840-2025         New Zealand          
#> # ℹ 6 more variables: reporting_polity_has_geometry <lgl>,
#> #   item_cbs_code_crop <dbl>, item_cbs_code_residue <dbl>, value <dbl>,
#> #   value_dm <dbl>, method_residue <chr>