Fast facts: land
Agriculture needs land. The 14.9 billion ha of the global surface are not all suitable for agricul-ture. In some regions the oceans and the surface are covered with permanent ice (arctic areas, glaciers in the high mountains). Large parts of the surface are mountainous and/or deserts. To-day, about 37% of the surface is used for agriculture (Table below). The other areas are randomly used for food hunting and gathering. Large areas are settlements without or very little (urban, peri-urban) agriculture. Deserts and rainforests are becoming farmed, increasingly, if irrigation or deforestation and drainage are possible. Many areas are protected to preserve wilderness and nature. Large areas are not farmed because they are under ice, like Greenland, Northern Territories of Canada and Alaska, the Siberian area of Russia and the vast Antarctica. Probably, in the future they are all farmed as well.
Table: Global land use and the share of agriculture in 1962 and 2021
Source: Designed with data from FAOstat (2024)
Only part of the land area is suitable for food production. 1.6 billion hectares are used for arable agriculture, 3.2 for permanent pasture and 0.1 for permanent crops. More land for food produc-tion is only available in the world to a limited extent (irrigation of dry areas, deforestation, ter-racing of mountains). A growing world population must make do with the available land area. Worldwide, the area of land used for agriculture has fallen from 5.6 ha in 1950 to 1.8 ha per person in 2020 (-67%). The available area per person in Africa has fallen particularly sharply from 9.4 to 1.8 ha (-81%).
Photo 1: Lava soils, commonly classified as volcanic soils or Andisols , form from weath-ered lava, ash, and volcanic ejecta, and they cover about 1% of the Earth’s ice-free land surface, yet support nearly 10% of the world’s population because of their agricultural productivity.
These soils develop relatively quickly in geological terms: fresh volcanic ash can begin trans-forming into soil within decades, while fully developed lava soils may form in 1,000–10,000 years, much faster than many sedimentary soils. Their fertility comes from high concentrations of minerals such as iron, magnesium, calcium, and potassium, often exceeding those of non-volcanic soils by 20–50%, depending on parent material. Lava soils are also notable for their physical properties: they can retain up to twice as much water as sandy soils while still main-taining good drainage due to their porous structure. Organic matter content can reach 8–15%, compared with 2–5% in many temperate mineral soils, enhancing nutrient availability and soil structure. However, these soils strongly bind phosphorus, sometimes making 50–90% of total phosphorus unavailable to plants without management. Found in regions such as Japan, Indo-nesia, Hawaii, Italy, and Central America, lava soils underpin high-value crops like coffee, grapes, and bananas, often producing yields 20–30% higher than comparable crops grown on non-volcanic soils when properly managed. Some regions do only exists because of Vulcan eruptions, like the Canary Islands. In 2021, the Tajogaite / Cumbre Vieja Vulcan on La Palma (Canary Islands) erupted and shows the devastation and agriculture potential. Many banana plantations have been destroyed in the 85 days of lava flow, but only four years later, the rich soils are recultivated.
Photo 2: Without water and temperature above 0°C, our planet would be covered with dry or cold deserts. Today, they occupy about one third of the surface of the Earth, the same coverage as cropland and grassland together.
Photo 3: Land from Sea. The Afsluitdijk is a 32-kilometer-long dam located in the Nether-lands, completed in 1932 as part of the Zuiderzee Works, a large-scale hydraulic engineering project. Its construction transformed the former saltwater inlet Zuiderzee into the freshwater lake known as the IJsselmeer by separating it from the Wadden Sea and the North Sea. The primary function of the Afsluitdijk is flood protection, significantly reducing the risk of storm surges affecting the central Netherlands. About 26% of the Netherlands is below mean sea level, 55% of the is vulnerable to flooding from sea or rivers. Around 60% of the population lives in these low-lying areas. This is why large-scale flood control systems like the Afsluitdijk, dikes, and storm surge barriers are essential for the country’s safety and water managementIn addition, it enabled large-scale land reclamation, leading to the creation of polders such as Flevoland. The dam also plays a key role in water management, regulating freshwater levels and supporting agriculture and drinking water supply. It is considered one of the most important achievements in coastal engineering and water management worldwide. About 1,650 square kilometers of land were reclaimed because of the Afsluitdijk and the Zuiderzee Works. Together, these pol-ders were created from the former Zuiderzee / IJsselmeer, turning seabed into usable land for agriculture, housing, and infrastructure. This makes it one of the largest and most successful land reclamation projects in the world.
Cold deserts are the Antarctic Desert and the Arctic Desert, which comprise together 2.8 billion ha. The deserts due to low rainfall are the Sahara Desert (0.9 billion ha), Great Australian Desert (2.7 billion ha), Arabian Desert (2.3 billion ha), Gobi Desert (1.3 billion ha), Kalahari Desert (100 million ha), Patagonia Desert (67 million ha), Syrian Desert (50 million ha), Great Basin Desert (50 million ha). Many deserts look like dead and unusable for agriculture, like the Jordanian steppe (part of the 500,000 km2 large Syrian desert) close to Amman and the glacier in Iceland. But some plants are adapted and survive under hot weather and very low water availability. Those dry areas are use with camel and sheep as low external input - low output system. A desert has less than 250 mm precipitation (rainfall, snow, mist, fog) per year or is too cold for plant growth. Plant cannot grow without water, and utilization must be economically. With irrigation or rainfall, agriculture would be possible in deserts. The natural vegetation in the desert in Jordan shows the potential. With unpredictable and irregular rainfall, the desert becomes immediately colored with flowering plants, and at least for some weeks. They ripe fast and die. The seeds wait for the next rainfall, sometimes. With irrigation those areas are suitable for crop production or intensive animal husbandry.
I