# Empirical View
# Land Use Change in the Very Long Run
Navin Ramankutty and Jonathan A. Foley have reconstructed the change in global agricultural land usage. In their very highly cited (>800 times) publication, Ramankutty and Foley (1999) have reconstructed the change between 1700 and 1992. In the equally famous update, Ramankutty et al. (2008) have presented estimates on global agricultural lands in the year 2000.1
There are two beautiful animations that show the change of agricultural land since 1700. Bill Rankin mapped the change between 1700 and 1990 at Radical Cartography (here). And on Navin Ramankutty’s personal academic website there is a video that shows the change between 1700 and 2000 (online here).
The changing global landscape of crop production, 1700-2000 – Alston, Babcock, and Pardey [eds.] (2010) [based on SAGE data]2
# Agricultural Land Use Change in the Last 50 and the Next 50 Years
Arable land per capita (ha in use per person) (1961-2050) – Jelle Bruinsma (2009) [FAO]3
The following graph includes a projection of global arable land for the period 2010-2060. While the authors of this paper forecast a slight decline of global farmland, the before-cited research by the FAO projects a slight increase of total global farmland.
Ausubel, Wernick, & Waggoner (2013) argue that ‘peak farm’ is already a reality, saying ‘while the ratio of arable land per unit of crop production shows improved efficiency of land use, the number of hectares of cropland has scarcely changed since 1990. Absent the 3.4 percent of arable land devoted to energy crops (Trostle 2008), absolute declines would have begun during the last decade.’4
Peaking farmland: extent of global arable land and permanent crops, 1961-2009, and our projection for 2010-2060 – Ausubel, Wernick, & Waggoner (2013)5
# World map of change in cropland area, 1960-2000 – Alston, Babcock, and Pardey [eds.] (2010) [based on SAGE data]6
# The Breakdown of Global Land Use Today
The graphic below details the breakdown of global land allocation and use based on areal extent. Only 71 percent of Earth’s land surface is defined as habitable. Humans use half of global habitable area for agricultural production (of the remainder, 37 percent is forested; 11 percent as shrubbery; and only one-percent is utilised as urban infrastructure).
More than three-quarters of our agricultural land is used for the rearing of livestock through a combination of grazing land and land used for animal feed production. Despite being dominant in land allocation for agriculture, meat and dairy products supply only 17 percent of global caloric supply and only 33 percent of global protein supply. In other words, the 11 million square kilometres used for crops supply more calories and protein for the global population than the almost 4-times larger area used for livestock.
# Global Agricultural Land Use Today
We use roughly half of global habitable land for agriculture. But how much of total land area is utilised for agriculture across the world? In the map below we see the share of total (both habitable and non-habitable) land area used for agriculture from 1961-2014.
There is large variability in the share of land a given country uses for agriculture. Allocation ranges from less than ten percent, particularly across countries in Sub-Saharan Africa and the Scandinavian region to close to 80 percent across most regions (including the UK, Uruguay, South Africa, Nigeria and Saudi Arabia). It’s important to note that this metric includes both land used for arable (cropland) production and pasture land for livestock grazing; this means that agriculture can consume a large share of land area, even in arid and semi-arid regions where extensive arable farming is not possible. We will explore this difference in cropland and pastureland in the following section.
If we view the map below in “chart” mode, we see how the allocation of land to agriculture has changed over time across the global regions. The share of land used for agriculture has been slowly increasing across most of the world’s regions over the past few decades. However, land use across Europe and Central Asia- particularly within the European Union (EU) zone- and North America has been declining.
# Arable agriculture (cropland)
There are two main uses of agricultural land: arable farming (which is land dedicated to growing crops), and pastureland (which includes meadows and pastures used for livestock rearing). In the chart below we see a global map of land used for arable agriculture (as a share of total land area).
For most countries, as we will show in the section below, land use for livestock grazing is dominant relative to arable farming. For most countries, land dedicated to cropland is typically below 20 percent, with many countries dedicating less than 10 percent. There are some notable exceptions, however; countries in South Asia and Europe allocate a large share of land area to arable farming. India, Bangladesh, Ukraine and Denmark all dedicated more than half of total land area to cropland in 2014.
# Pastureland (permanent meadows and pasture)
For most countries, the majority of agricultural land is used for livestock rearing in the form of pastureland. In the map below we see the share of permanent meadows and pasture as a percentage of total land area.
As a contrast to arable farming, land use for livestock in Europe and South Asia, in particular, is typically less than 20 percent. However, most continental regions have countries where pastureland reaches close to half of total land area. In some countries (particularly in Central Asia, including Mongolia, Kazakhstan, and Turkmenistan) this can reach up to 70 percent. Livestock farming can take place across a range of diverse climatic and environmental regions (for example, ranging from cattle rearing in temperate regions to sheep farming in hilly and semi-arid terrain); meaning that this type of agriculture is potentially less geographically-constrained than arable farming.
# Land Use Change by Crops
# English arable land use (millions of acres) by crop, 1270-1870 – Max Roser7
Global harvested area by crop category, 1961-2007 – Alston, Babcock, and Pardey [eds.] (2010)8
# Agricultural Land Use Today by Crops
World maps of crop areas (maize, rice, wheat, and soybeans) – Monfreda, Ramankutty, Foley (2008)9
Land use in the USA – percent of land devoted to each crop by county, 2007 – Radical Cartography10
# Correlates, Determinants & Consequences
# Higher yields means we are producing more food without extending agricultural land
The following graph shows that to produce an equivalent aggregate of crop production in 2012 required only about 32% of the land needed in 1961. The agricultural production index (PIN) use here is the sum of agricultural commodities produced (after deductions of quantities used as seed and feed). It is weighted by the commodity prices. The FAO explains the construction of the PIN in detail here.
The idea for this chart is taken from Ausubel, Wernick, and Waggoner (2013).11 The authors write: ‘A combination of agricultural technologies raised yields, keeping downward pressure on the extent of cropland, sparing land for nature.
Countering the global rise of population and affluence by parents and workers, consumers and farmers restrained the expansion of arable land by changing tastes and lifting yields. The noticeable shrinkage in the extent of cropland as a function of the Crop Production index since 1990 (Figure below) provides encouragement that farmers will continue sparing land.’
Arable land per crop production index for the world, since 196112
# The trade-off between increasing yields and increasing land use
As we explore in our entry on Yields, the trade-off between land use for agriculture and yields is clearly exemplified in a comparison between cereal production in Asia and Sub-Saharan Africa. Expansion of cereal production has followed very different paths in Sub-Saharan Africa and Asia. Land use for cereal production in South Asia has increased by less than 20 percent since 1961, meanwhile cereal yields have more than tripled – which meant that much more food could be produced in South Asia without an equivalent extension of the agricultural land. This is in strong contrast to Sub-Saharan Africa where the area of land used for cereal production has more than doubled since 1961 and yields have only increased by 80 percent.
# Decoupling agricultural output from land use by increasing yields
Area harvested and production for wheat in France 1820-2010, rice in China 1920-2010, and wheat in Egypt 1890-2010 – Ausubel, Wernick, & Waggoner (2013)13
# Data Quality & Definition
The Land Area of the World is 13,003 million ha. 4,889 million ha are classified as ‘agricultural area’ by the FAO (this is 37.6% of the Land Area).
The agricultural area use is divided into 3 categories: arable land (28% of the global agricultural area), permanent crops (3%) and permanent meadows and pastures (69%) which account for the largest share of the world’s agricultural area.14
What do these words mean?
The agricultural area is the sum of arable land, permanent crops, permanent meadows and pastures.
The FAO definition for arable land is land under temporary agricultural crops (multiple-cropped areas are counted only once), temporary meadows for mowing or pasture, land under market and kitchen gardens and land temporarily fallow (less than five years). The abandoned land resulting from shifting cultivation is not included in this category. Data for “Arable land” are not meant to indicate the amount of land that is potentially cultivable.’15
The same source defines permanent crops as follows: ‘Permanent crops are divided into temporary and permanent crops. Permanent crops are sown or planted once, and then occupy the land for some years and need not be replanted after each annual harvest, such as cocoa, coffee and rubber. This category includes flowering shrubs, fruit trees, nut trees and vines, but excludes trees grown for wood or timber.
And again from the same source the definition for permanent meadows and pastures is ‘land used permanently (five years or more) to grow herbaceous forage crops, either cultivated or growing wild (wild prairie or grazing land).’
The FAO definition for fallow land is ‘the cultivated land that is not seeded for one or more growing seasons. The maximum idle period is usually less than five years.’
# Data Sources
The FAO Land Use Database is online here. It includes several datasets on land use for countries and world regions since 1961.
Through Gapminder (here) it is possible to visualize data on agricultural land (as % of land) for the period from 1961 to 2009 and to plot this data against a second variable.