Competition for Land Area

  • Today more than 800 million people worldwide are starving, which means more than one in ten! This is so despite the fact that agricultural productivity has increased continuously in recent decades. From this follows that the agricultural land area is the limiting good. In the past, however, this area has declined steadily, albeit slowly.

  • The share of animal-based food is currently globally increasing, partly because it is growing in China and India. In Europe a slow decline can be observed. The production of animal-based food is very inefficient. On global average, 80% of agricultural land is used to produce animal-based food, which covers less than 20% of calories supply. Also, two calories of feed are required for each calorie of animal-based food.

  • Due to the strong population growth, the land area available per person for food production is steadily decreasing. According to the medium variant of population growth, it decreases by a factor of about 1.5 until 2100 and by a factor of more than 2 according to the high variant. Agricultural productivity must therefore compensate for this by increasing intensification. Population growth increases exponentially, while agricultural productivity increases only linearly.

  • In both, the high and the medium variant of population growth, agricultural land area will always have to be farmed at the limits of its capacity, despite maximum intensification of agriculture, if the proportion of animal-based food continues to be as high as it has been in the past. In the high variant of population growth even forests must be converted into agriculturally used land in order to adequately feed all people.

  • In many scenarios, bio-energy is also intensely used to limit climate change, for example by BECCS (bio-energy and carbon capture and storage). The production of corresponding energy plants also competes for agriculturally usable land. Bio-energy based exclusively on waste from food production, which means the exclusive use of 'third-generation' biomass, cannot cover a significant proportion of our energy consumption. The use of bio-energy therefore means more hunger in the world for the high and medium population variant - even today.

  • The same applies for the production of bio-based materials such as plastics, detergents, etc. Also this demand cannot be fulfilled from third-generation biomass alone, so that a bio-economy also for materials production requires dedicated agricultural land and thus increases hunger in the world as long as we do not change our behavior.

The discussion presented here is based on a publication in ChemBioEng Reviews:
Pfennig, A.: Sustainable Bio- or CO2-Economy: Chances, Risks, and Systems Perspective.
ChemBioEng Reviews (2019) 6(3), 90-104.