Grassland share of synthetic nitrogen by country and year
Source:R/datasets.R
lassaletta_grassland_share.RdCountry-level time series of the share of synthetic nitrogen applied to grassland (versus cropland). Used to split national N totals between land use types in the WHEP nitrogen pipeline.
The series is the per-country grassland proportion that Lassaletta et al. (2014) subtracted from FAO national fertiliser use to obtain nitrogen input to cropland: "FAO data on annual per country synthetic fertilizer use refer to total use in agriculture and is provided without distinction between arable and grassland. We therefore had to subtract from these figures the proportion used for grassland fertilization, which in some European countries such as Ireland and the Netherlands accounts for a significant proportion." The proportions in that paper rest in turn on Richard (1951), Power and Alessi (1971), Anonymous (1992), FAO (2006) and Heffer (2013), detailed in its supplementary material S1.
Format
A tibble with one row per country-year combination containing:
Country: Country name, in the FAO-era vocabulary of the source ("Belgium-Luxemburg","Czechoslovakia","Ethiopia PDR","Yugoslav SFR","FSU").year: Year (numeric), 1961-2009 for every label.grass_share: Share of synthetic N applied to grassland, as a fraction in 0-1. The tracked CSV holds the same numbers as percentages.
141 labels x 49 years = 6,909 rows. 4,798 of them are exactly 0 and only 53 labels are ever non-zero; the largest shares are Ireland (0.88) and the Netherlands (0.71), the two countries the source singles out. Many series are linear ramps from 0 in 1961 up to the first documented value, so a value is not an observation for its own year.
The label set is not a partition: it carries a historical entity and
its modern successors side by side for the whole span, so Sudan,
Sudan (former) and South Sudan all appear for 1961-2009, with Sudan
and Sudan (former) carrying identical values. A consumer that resolves
these labels to area codes therefore needs a duplicate-key rule.
Source
Lassaletta, L., Billen, G., Grizzetti, B., Anglade, J., & Garnier, J. (2014). 50 year trends in nitrogen use efficiency of world cropping systems: the relationship between yield and nitrogen input to cropland. Environmental Research Letters, 9(10), 105011. doi:10.1088/1748-9326/9/10/105011 . The per-country values are that paper's supplementary material S1 and its Annex 1 CSV.
The attribution is evidential, not byte-verified. The tracked CSV arrived from an upstream project that labelled it with this DOI; its span (1961-2009), its country vocabulary and its two extreme countries all agree with the paper, and at 19,531 bytes the wide original is within 2% of the 19.2 KB IOP reports for Annex 1. IOP blocks automated download of that file, so the two were never compared row by row, and the duplicated Sudan labels may be the paper's or a later addition.
Examples
head(lassaletta_grassland_share)
#> # A tibble: 6 × 3
#> Country year grass_share
#> <chr> <dbl> <dbl>
#> 1 Afghanistan 1961 0
#> 2 Afghanistan 1962 0
#> 3 Afghanistan 1963 0
#> 4 Afghanistan 1964 0
#> 5 Afghanistan 1965 0
#> 6 Afghanistan 1966 0