Global cropland expansion and biodiversity loss
19 November 2019
Modern science defines biodiversity as “the sum total of all of the plants, animals, fungi, and microorganisms on Earth”, which “can be observed and measured at any spatial scale ranging from microsites and habitat patches to the entire biosphere”. On both local and global scales, healthy biological diversity is crucially important for the future of our planet. However, over the last few years, scientists have been sounding the alarm to international community about rapidly declining numbers of wildlife populations and continuing threats of extinction of numerous species worldwide. The studies insist that biodiversity loss inevitably impacts the sustainability of entire ecosystem and, accordingly, wellbeing of humans.
Between 1970 and 2014, world’s populations of mammals, birds, fish, reptiles and amphibians reduced by 60% on average. Among the main drivers of global biodiversity decline named in scientific literature are the loss and fragmentation of natural habitats due to land clearing activities associated mainly with cropland expansion as well as intensification of agricultural practices.
Largescaleagriculture.com has summarized the evidence-based research related to farmland expansion in an attempt to find out, how commercial agriculture impacts biodiversity and to what extent the trend of farm consolidation jeopardizes the sustainability of our ecosystem.
Converting wildland into farmland
According to the Food and Agriculture Organization (FAO) of the United Nations, croplands make up 12% of the Earth’s terrestrial area (1.53 billion hectares), while pastures occupy 26% of it (3.38 billion hectares). The past decades witnessed a dramatic farmland expansion, with an upward trend. In particular, between 1985 and 2005, farmland area increased by 154 million hectares or about 3% worldwide, mainly due to forest clearings in the tropical regions (Central and South America, and Central Africa). These changes have been accompanied by a tendency toward farm consolidation worldwide including the countries of South America, e.g. Brazil and Argentina. As of 2006, large farms operating 8,000 hectares and more accounted for about 30 million hectares or 62% of the total farmland in the state of Matto Grosso, Brazil’s main crop producing region.
More on deforestation
Some studies claim that commercial agriculture is the key driver behind deforestation, accounting for 40% of deforestation in tropical and sub-tropical regions. It is fair to say that subsistence agriculture causes another 33% of deforestation in the same regions, as stated in the study.
According to FAO, commercial agriculture accounted for 70% of deforestation in South America and 30% in Africa (where small-scale farming is still a major driver of deforestation) between 2000 and 2010. In particular, the Amazon region has been worst affected by deforestation since 1990 due to growing demand for agricultural products from external markets and the resulting proliferation of large scale grassland pastures and soybean and palm oil fields. Notably, South and Central America witnessed an 89% drop in vertebrate populations within the last 50 years, largely due to deforestation.
Mass media often associates such negative developments with the activities of large agricultural companies. For instance, the world’s largest Brazil-based meat producers Marfrig, JBS, BRF and others have been lately accused of buying cattle from illegal Amazon deforesters. The companies, on the contrary, claim to adopt sustainable agricultural practices and strictly select the suppliers not involved in any illegal actions. BRF reports to have planted 31,802 hectares of renewable forest across Brazil in order to mitigate its impact on environment.
Forecast: cropland expansion
In the view of global population and economic growth, further expansion of cropland areas and farm consolidation are likely to continue in the upcoming decades. About 90% of the remaining 1.8 billion hectares of land potentially suitable for farming are located in South America and sub-Saharan Africa, with more than half of it accumulated in just seven countries - Brazil, the Democratic Republic of the Congo, the Sudan, Angola, Argentina, Colombia and Bolivia.
A notable case is the joint Brazilian-Japanese campaign known as Prosavana aimed at boosting agricultural production by converting over 10.7 million hectares of land across Mozambique into intensive farming clusters similar to the ones in the Brazilian cerrado. Launched back in 2009, the program fell short of expectations, and its future remains uncertain as it faced strong resistance on behalf of local farmers.
In general, FAO forecasts a 5.8%-net increase in the arable area (59 million hectares) for developing countries from 2015 until 2030. The strongest farmland expansion is expected to take place in South America, particularly in Argentina, Bolivia, and Uruguay, posing a risk to protection of biodiversity hotspots in the region.
Limited land resources and biodiversity crisis foster scientific community and policy-makers to search for alternative and less consequential ways to meet global demand for food. Accordingly, cropland expansion might represent lower threats to conservation of biodiversity in the areas like Eastern Europe, sub-Saharan Africa, Northeast China or Midwest of North America due to initially lower species richness.
Another option which might help to suspend land clearing activities and is commonly mentioned in scientific literature is “land sparing”. In this case, further farmland expansion could be prevented by increasing yields on existing farmland. Such strategy would mean increased application of fertilizers and agrochemicals alongside overall intensification of agricultural practices, known as the second major driver of biodiversity loss. Could this be the lesser of two evils?
To be continued