In agriculture, monoculture is the practice of growing one crop species in a field at a time. Monocultures increase ease and efficiency in planting, managing, and harvesting crops short-term, often with the help of machinery. However, monocultures are more susceptible to diseases or pest outbreaks long-term due to localized reductions in biodiversity and nutrient depletion. Crop diversity can be added both in time, as with a crop rotation or sequence, or in space, with a polyculture or intercropping. Monoculture practices have been linked via several pathways to negatively impact human health from a One Health perspective. These links include but are not limited to environmental degradation, increased pest and disease outbreaks, greater pesticide/herbicide use, and reductions in dietary diversity (associated with diet-related disease burden including cardiovascular disease and diabetes).
Monocultures appear in contexts outside of agriculture and food production. Grass lawns are a common form of residential monocultures. Several monocultures, including single-species forest plantations, have become increasingly abundant throughout the tropics following market globalization, impacting local communities.
Genetic monocultures refer to crops that have little to no genetic variation. This is achieved using cultivars, made through processes of propagation and selective breeding, and can make populations susceptible to diseases which can rapidly spread across large areas. This widespread susceptibility ultimately endangers food security for regions dependent on such food supply.
Agroecological practices, silvo-pastoral systems, and mixed-species plantations are common alternatives to monoculture that help preserve biodiversity while maintaining productivity. These practices offer resilience to possible negative human and environmental health impacts.
Agriculture Agricultural monocultures refer to the practice of planting one crop species in a field. Monoculture is widely used in intensive farming and in organic farming. In crop monocultures, each plant in a field has the same standardized planting, maintenance, and harvesting requirements resulting in greater yields and lower costs. When a crop is matched to its well-managed environment, a monoculture can produce higher yields than a polyculture. Modern practices such as monoculture planting and the use of synthesized fertilizers have reduced the amount of additional land needed to produce food, called land sparing. +Diversity of crops in space and time; monocultures and polycultures, and rotations of both.Diversity in timeLowHigherCyclicDynamic (non-cyclic)Diversity in spaceLowMonoculture, one species in a fieldContinuous monoculture,
monocroppingCrop rotation (rotation of monocultures)Sequence of monoculturesHigherPolyculture, two or more species intermingled in a field (intercropping)Continuous polycultureRotation of polyculturesSequence of polycultures
Note that the distinction between monoculture and polyculture is not the same as between monocropping and intercropping. The first two describe diversity in space, as does intercropping. Monocropping and crop rotation describe diversity over time.
Environmental impacts Monocultures of perennials, such as African palm oil, sugarcane, tea and pines, can change soil chemistry leading to soil acidification, degradation, and soil-borne diseases, ultimately having a negative impact on agricultural productivity and sustainability. The use of unregulated irrigation practices on popular monocultures, such as soy, can also lead to erosion and water loss.
As soil health declines, use of synthetic fertilizers on monocultural fields increases, often having negative implications on human health via chemical run-off. For example, excess nitrogen from synthetic fertilizers can leach into ground and surface waters, leading to nitrate contamination of drinking water. This contamination is associated with serious health risks such as methemoglobinemia ("blue baby syndrome") and the formation of carcinogenic compounds such as nitrosamines within the human digestive system.
Agricultural runoff can also degrade aquatic ecosystems through nutrient loading, which subsequently leads to eutrophication harmful algal blooms (HABs). This process can compromise water quality and safety as these blooms produce potent cyanotoxins such as microcystin, which can bioaccumulate in fish and shellfish. Human consumption can ultimately lead to liver damage, neurotoxicity, and gastrointestinal illness.
In addition to soil depletion, monocultures can cause significant reductions in biodiversity due to unavailability of resources, native species displacement, and loss of genetic variation. Following large-scale oil palm plantations in Latin America, research has revealed extensive declines in mammal, bird, amphibian, and pollinator diversity, particularly in Colombia and Brazil.
Due to insufficient biodiversity and population balance, monocultures are associated with higher rates of disease and pest outbreaks. In response, pesticides are widely applied to agricultural fields, further harming insect and pollinator diversity and human health. Increasing rotations of crop monocultures or using alternatives agricultural practices can help mitigate the risk of disease and attack.
Social impacts Environmental consequences of monocultural farming have notable social impacts, commonly concentrated to the reduction of small-scale farmers and pesticide-related health issues. Monoculture is contradictive to several primitive, more sustainable farming practices utilized by small-scale farmers. Following pest outbreaks, over 600 million liters of pesticides are sprayed annually, contaminating nearby small-scale farming and causing communal health decline. This link between monoculture practices, increased pesticide use, and subsequent human health risks can be illustrated well by a One Health perspective, which emphasizes the interconnectedness of environmental and human health. Chronic exposure to commonly used pesticides has been associated with various negative health outcomes, including neurological disorders such as Alzheimer's disease and amyotrophic lateral sclerosis, brain tumors, leukemia, non-Hodgkin lymphoma, and a wide range of other gastrointestinal, dermatological, and respiratory illnesses. Notably, the burden of exposure to such pesticides disproportionately affects vulnerable populations including agricultural workers, their families (including children), and residents of nearby communities. These disparities underscore the importance of environmental justice within the One Health framework.
Monoculture practices also influence human diets in ways that can negatively impact human health. The global expansion of monoculture practices has led to the selection of staple crops such as wheat, rice, soy, corn, and sugar on an international level. This has reduced dietary diversity around the world and has promoted calorie-dense but nutrient-poor foods. This change in human dietary patterns has been associated with a decreased intake of essential micronutrients, contributing simultaneously to both nutritional deficiencies as well as overnutrition-related non-communicable diseases such as obesity and type 2 diabetes. Monoculture systems prioritize high-yield crops that can be converted into ultra-processed foods, reinforcing dietary trends towards refined carbohydrates, sugars, and unhealthy fats. Within a One Health perspective, these changes illustrate how agricultural practices can profoundly reduce diversity within the human diet and negatively impact human health outcomes.
Agro-extractivism Agro-extractivism is a form of extractivism in which foreign territorial, political, and economical dominance over agriculture is motivated by the large-scale production and exportation of agricultural commodities, often in the form of monocultures.
Several monocultures in the Global South, such as sugar and coffee, were first planted in the 1800s following European colonization. These plantations used slave labor, setting a precedent for agriculture being a field dominated by foreign entities in the rest of Latin America and the Caribbean. This social framework has shaped the oppression of Black people and smaller-scale farmers in the face of present-day land acquisition for monocultural use.
The large-scale establishment of monocultures in the tropics has led to hindrance of local small-scale farms and indigenous land rights in the forms of reduced food sovereignty, food security, land and water access, and hunting. Land privatization and pressure for monocultural expansion by larger companies takes different forms: silent evictions, violence, and reverse leasing arrangements. Introduction to global trade makes small-scale farmers vulnerable to international demand, prices, and variations in climate affecting crop production. Farmers who make contracts or take out loans with large corporations can face debt and loss of land if they fail to meet certain crop yields or profit.
Monocultures are an aspect of agro-extractivism on account of high percentages of the produced crop being exported for processing and marketing by large transnational corporations, often in developed countries. For instance, following the North American Free Trade Agreement (NAFTA), agave production increased three-fold in Mexico from 1995 to 2019 due to foreign consumption, specifically by the United States. Pararguay sees similar demands with soy crops, exporting the majority of production without nutrients returning to native soil. More than 46 million hectares of soy has been planted across South America while over half a million hectares of land are being deforested annually to make land for cultivation. Some international companies relevant in the field of agro-extractivist monocultures are Syngenta and Bayer (biotech), Los Grobo, CRESUD, El Tejar, and Maggi (landowners), and Cargill, ADM, and Bunge (grain and seed providers).
From a One Health perspective, such monoculture practices contribute to soil nutrient depletion, which has subsequent effects on the ecosystem and ultimately, human health. Repeated cultivation of a single crop exhausts soil nutrients and reduces microbial diversity, thereby diminishing soil fertility and increasing dependence on synthetic fertilizers. This degradation of soil quality not only jeopardizes long-term productivity, but also reduces the nutritional quality of crops, with the nutrient-poor soil inherently yielding foods with reduced nutrient density. In populations that rely heavily on staple crops, deficiencies in essential micronutrients such as zinc or iron can contribute to malnutrition-related health issues. Within a One Health framework, this illustrates how soil degradation driven by monoculture or similar practices can be directly linked to negative human health outcomes.
Forestry In forestry, monoculture refers to plantations of one species of tree.Monoculture Forestry In many areas of the world, forest monocultures are planted as an efficient way to produce and harvest timber. Because timber harvest from monoculture forests is often an export-driven industry, these plantations can be a form of extractivism. Following deforestation, monoculture afforestation has become increasingly popular due to the necessity for ecosystem services, such as mitigating the effects of climate change via carbon sequestration and gas regulation. Eucalyptus, pines, and acacias are examples of popular monocultures being utilized in the tropics and the Global South following rainforest deforestation.