Palm oil

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https://en.wikipedia.org/wiki/Palm_oil

Palm oil block showing the lighter color that results from boiling

Palm oil is an edible vegetable oil derived from the mesocarp (reddish pulp) of the fruit of oil palms. The oil is used in food manufacturing, in beauty products, and as biofuel. Palm oil accounted for about 36% of global oils produced from oil crops in 2014. Palm oils are easier to stabilize and maintain quality of flavor and consistency in ultra-processed foods, so they are frequently favored by food manufacturers. Globally, humans consumed an average of 7.7 kg (17 lb) of palm oil per person in 2015. Demand has also increased for other uses, such as cosmetics and biofuels, encouraging the growth of palm oil plantations in tropical countries.

The use of palm oil has attracted the concern of environmental and human right groups. The palm oil industry is a significant contributor to deforestation in the tropics where palms are grown and has been cited as a factor in social problems due to allegations of human rights violations among growers. The Roundtable on Sustainable Palm Oil was formed in 2004 to promote the more sustainable and ethical production of palm oil. However, very little palm oil is certified through the organization, and some groups have criticized it as greenwashing.

In 2018, a report by the International Union for Conservation of Nature acknowledged that palm oil is much more efficient than other oils in terms of land and water usage; however, deforestation causes more biodiversity loss than switching to other oils. The biggest global producers of palm oil are Indonesia, who produced 60% of it in 2022, followed by Malaysia, Thailand, and Nigeria. Indonesia produces biodiesel primarily from palm oil.

History

Oil palms (Elaeis guineensis)

Humans used oil palms as far back as 5,000 years. In the late 1800s, archaeologists discovered a substance that they concluded was originally palm oil in a tomb at Abydos dating back to 3,000 BCE.

Palm oil from Elaeis guineensis has long been recognized in West and Central African countries, used widely as a cooking oil. European merchants trading with West Africa occasionally purchased palm oil for use as a cooking oil in Europe.

Palm oil became a highly sought-after commodity by British traders for use as an industrial lubricant for machinery during Britain's Industrial Revolution. Palm oil formed the basis of soap products, such as Lever Brothers' (now Unilever) "Sunlight" soap, and the American Palmolive brand.

By around 1870, palm oil constituted the primary export of some West African countries, which often led to oppressive labor practices, as highlighted in the account of Abina Mansah's life. However, this was overtaken by cocoa in the 1880s with the introduction of colonial European cocoa plantations.

Processing

Oil palm fruits on the tree

An oil palm stem, weighing about 10 kg (22 lb), with some of its fruits picked

Palm oil is naturally reddish in color because of a high beta-carotene content. It is not to be confused with palm kernel oil derived from the kernel of the same fruit or coconut oil derived from the kernel of the coconut palm (Cocos nucifera). The differences are in color (raw palm kernel oil lacks carotenoids and is not red), and in saturated fat content: palm mesocarp oil is 49% saturated, while palm kernel oil and coconut oil are 81% and 86% saturated fats, respectively. However, crude red palm oil that has been refined, neutralized, bleached and deodorized, a common commodity called RBD (refined, bleached, and deodorized) palm oil, does not contain carotenoids. Many industrial food applications of palm oil use fractionated components of palm oil (often listed as "modified palm oil") whose saturation levels can reach 90%; these "modified" palm oils can become highly saturated, but are not necessarily hydrogenated.

The oil palm produces bunches containing many fruits with the fleshy mesocarp enclosing a kernel that is covered by a very hard shell. The FAO considers palm oil (coming from the pulp) and palm kernels to be primary products. The oil extraction rate from a bunch varies from 17 to 27% for palm oil, and from 4 to 10% for palm kernels.

Along with coconut oil, palm oil is one of the few highly saturated vegetable fats and is semisolid at room temperature. Palm oil is a common cooking ingredient in the tropical belt of Africa, Southeast Asia and parts of Brazil. Its use in the commercial food industry in other parts of the world is widespread because of its lower cost and the high oxidative stability (saturation) of the refined product when used for frying. One source reported that humans consumed an average 17 pounds (7.7 kg) of palm oil per person in 2015.

Extraction

Red Palm oil being sold on the side of the road in plastic bottles in Ghana. Artisanal production of palm oil is common in Ghana, providing a key staple food stuff in most traditional cooking.

Palm oil is traditionally, and still industrially, produced by milling the fruits of oil palm.

Besides milling, palm oil is produced by cold-pressing the fruit of the oil palm since the 1990s. This type of artisanal palm oil is usually not further refined, so they keep the natural red color. It is bottled for use as a cooking oil, in addition to other uses such as being blended into mayonnaise and vegetable oil.

The result of milling or cold-pressing is a mixture of water, crude palm oil, and fibers from the palm fruit. A minimum degree of processing is required to obtain the oil. The mixture is first passed through a filter to remove the solids, then separated by density to removed the water. Density treatment can also act as a basic form of degumming, provided that the fruit is steamed before milling to hydrolyze the gum, at a cost of also losing some triglycerides to hydrolysis.

The result of basic processing is called a "crude palm oil" or a "red palm oil", referring to its intense color due to the high caretinoid content. Red palm oil is a traditional cooking oil in West Africa. The free fatty acids within provide a "bite" to the flavor. The triglyceride part is around 50% saturated fat—considerably less than palm kernel oil—and 40% monounsaturated fat and 10% polyunsaturated fat. It is a source of Vitamin A and Vitamin E.

Refining

See also: Edible oil refining

Worker walking near the boundary of an oil mill in Malaysia. Palm oil production is important part of economies in many parts of rural Malaysia, but is also a source of environmental conflict

Crude PO can be refined to remove its non-triglyceride components.

1. Bleaching removes color from the oil. This is achieved by adding a clay absorbent called bleaching earth in a vacuum mixer.
2. Filters remove the clay from the oil.
3. The oil enters the deodorizer, which is responsible for removing free fatty acids (FFA) generated by hydrolysis. One type of deodorizer works by distillating out the FFAs using a set of different temperatures. The FFA is collected as "palm fatty acid distillate" (PFAD). PFAD is itself a valuable product used in the manufacture of soaps, washing powder and other products.
4. The final, refined oil is called "refined, bleached and deodorized palm oil" (RBD PO). RBD PO is the basic palm oil sold on the world's commodity markets.

RBD PO is also known as white palm oil. It can be further fractionated using the different melting points of its components. The part with a higher melting point, which crystalizes out as a solid earlier, is called palm stearin. It consists of mostly saturated fats. The remaining liquid part is called palm olein. It is also possible to fractionate at a different point of processing, even with crude palm oil.

RBD PO, or "palm shortening", is extensively used in food manufacture. It is valued for its low polyunsaturated fat content, which offers high stability against rancidity and allows it to replace hydrogenated fats in a variety of baked and fried products.

Uses

Palm oil production is done in some parts of the world artisanally, and the locally produced oil is used for food, handicrafts and other products. This woman in the Democratic Republic of the Congo is showing the palm fruit above a pot for processing the fruit.

In food

The highly saturated nature of palm oil renders it solid at room temperature in temperate regions, making it a cheap substitute for butter or hydrogenated vegetable oils in uses where solid fat is desirable, such as the making of pastry dough and baked goods. Palm oil is used in West African cuisine such as egusi soup and okra soup. Palm oil is sometimes used as a minor ingredient in calf milk replacer.

Non-food consumer products

Palm oil is pervasively used in personal care and cleaning products, and it provides the foaming agent in nearly every soap, shampoo, or detergent. Around 70% of personal care products including soap, shampoo, makeup, and lotion, contain ingredients derived from palm oil. However, there are more than 200 different names for these palm oil ingredients and only 10% of them include the word "palm".

Biomass and biofuels

Palm oil is used to produce both methyl ester and hydrodeoxygenated biodiesel. Palm oil methyl ester is created through a process called transesterification. Palm oil biodiesel is often blended with other fuels to create palm oil biodiesel blends. Palm oil biodiesel meets the European EN 14214 standard for biodiesels. Hydrodeoxygenated biodiesel is produced by direct hydrogenolysis of the fat into alkanes and propane. The world's largest palm oil biodiesel plant is the €550 million Finnish-operated Neste Oil biodiesel plant in Singapore, which opened in 2011 with a capacity of 800,000 tons per year and produces hydrodeoxygenated NEXBTL biodiesel from palm oil imported from Malaysia and Indonesia.

Significant amounts of palm oil exports to Europe are converted to biodiesel (as of early 2018: Indonesia: 40%, Malaysia 30%). In 2014, almost half of all the palm oil in Europe was burned as car and truck fuel. As of 2018, one-half of Europe's palm oil imports were used for biodiesel. Use of palm oil as biodiesel generates three times the carbon emissions as using fossil fuel, and, for example, "biodiesel made from Indonesian palm oil makes the global carbon problem worse, not better."

There are pressures for increased oil palm production from Indonesian palm-based biodiesel programs. The biodiesel currently contains a 30:70 palm oil to conventional diesel ratio (known as B30) at the gas pumps. The Indonesian government is aiming to produce 100% palm oil biodiesel (or B100) to transition out of using conventional diesel. The Indonesian government has estimated it would need to establish approximately 15 million hectares of oil palm plantations to meet these future demands.

The organic waste matter that is produced when processing oil palm, including oil palm shells and oil palm fruit bunches, can also be used to produce energy. This waste material can be converted into pellets that can be used as a biofuel. Additionally, palm oil that has been used to fry foods can be converted into methyl esters for biodiesel. The used cooking oil is chemically treated to create a biodiesel similar to petroleum diesel.

In wound care

Although palm oil is applied to wounds for its supposed antimicrobial effects, research does not confirm its effectiveness.

Production

In 2022–2023, world production of palm oil was 78 million metric tons (86 million short tons). The annual production of palm oil is projected to reach 240 million metric tons (260 million short tons) by 2050. During the 2022 food crises instigated by the Russian invasion of Ukraine and crop failures in other parts of the world due to extreme weather caused by climate change, the Indonesian government banned exports of palm oil. This combined with a reduced harvest in Malaysia greatly increased global prices, while reducing availability causing ripple effects in the global supply chain. On 23 May 2022, the Indonesian government reopened trading hoping to balance supplies.

Indonesia

Main article: Palm oil production in Indonesia

A palm oil plantation in Indonesia

Indonesia is the world's largest producer of palm oil, surpassing Malaysia in 2006, producing more than 20.9 million metric tons (23.0 million short tons), a number that has since risen to over 34.5 million metric tons (38.0 million short tons) (2016 output). Indonesia expects to double production by the end of 2030. By 2019, this number was 51.8 million metric tons (57.1 million short tons). At the end of 2010, 60% of the output was exported in the form of crude palm oil. FAO data shows production increased by over 400% between 1994 and 2004, to over 8.7 million metric tons (9.6 million short tons).

Malaysia

Main article: Palm oil production in Malaysia

A palm oil mill located on a palm oil plantation in Malaysia

A satellite image showing deforestation in Malaysian Borneo to allow the plantation of oil palm

Malaysia is the world's second largest producer of palm oil. In 1992, in response to concerns about deforestation, the Government of Malaysia pledged to limit the expansion of palm oil plantations by retaining a minimum of half the nation's land as forest cover.

In 2012, the country  produced 18.8 million metric tons (20.7 million short tons) of crude palm oil on roughly 5,000,000 hectares (19,000 sq mi) of land. Though Indonesia produces more palm oil, Malaysia is the world's largest exporter of palm oil having exported 18 million metric tons (20 million short tons) of palm oil products in 2011. India, China, Pakistan, the European Union and the United States are the primary importers of Malaysian palm oil products. In 2016, palm oil prices jumped to a four-year high days after Trump's election victory in the US.

Nigeria

As of 2018, Nigeria was the third-largest producer, with approximately 2.3 million hectares (5.7 million acres) under cultivation. Both small- and large-scale producers participate in the industry. In much of the Niger Delta, palm oil is commonoly referred to as "red oil" (or red gold) to distinguish it from the "black oil" (crude oil) which dominates production.

Thailand

Thailand is the world's third largest producer of crude palm oil, producing approximately 2 million metric tons (2.2 million short tons) per year, or 1.2% of global output. Nearly all of Thai production is consumed locally. Almost 85% of palm plantations and extraction mills are in south Thailand. At year-end 2016, 4.7 to 5.8 million rai (750,000 to 930,000 hectares; 1,900,000 to 2,300,000 acres) were planted in oil palms, employing 300,000 farmers, mostly on small landholdings of 20 rai (3.2 hectares; 7.9 acres). ASEAN as a region accounts for 52.5 million metric tons (57.9 million short tons) of palm oil production, about 85% of the world total and more than 90% of global exports. Indonesia accounts for 52% of world exports. Malaysian exports total 38%. The biggest consumers of palm oil are India, the European Union, and China, with the three consuming nearly 50% of world exports. Thailand's Department of Internal Trade (DIT) usually sets the price of crude palm oil and refined palm oil Thai farmers have a relatively low yield compared to those in Malaysia and Indonesia. Thai palm oil crops yield 4–17% oil compared to around 20% in competing countries. In addition, Indonesian and Malaysian oil palm plantations are 10 times the size of Thai plantations.

Benin

Palm is native to the wetlands of western Africa, and south Benin already hosts many palm plantations. Its 'Agricultural Revival Programme' has identified many thousands of hectares of land as suitable for new oil palm export plantations. In spite of the economic benefits, Non-governmental organisations (NGOs), such as Nature Tropicale, claim biofuels will compete with domestic food production in some existing prime agricultural sites. Other areas comprise peat land, whose drainage would have a deleterious environmental impact. They are also concerned genetically modified plants will be introduced into the region, jeopardizing the current premium paid for their non-GM crops.

According to recent article by National Geographic, most palm oil in Benin is still produced by women for domestic use. The FAO additionally states that peasants in Benin practice agroecology. They harvest palm fruit from small farms and the palm oil is mostly used for local consumption.

Cameroon

Cameroon had a production project underway initiated by Herakles Farms in the US. However, the project was halted under the pressure of civil society organizations in Cameroon. Before the project was halted, Herakles left the Roundtable on Sustainable Palm Oil early in negotiations. The project has been controversial due to opposition from villagers and the location of the project in a sensitive region for biodiversity.

Colombia

In 2018, total palm oil production in Colombia reached 1.6 million metric tons (1.8 million short tons), representing some 8% of national agricultural GDP and benefiting mainly smallholders (65% of Colombia's palm oil sector). According to a study from the Environmental, Science and Policy, Colombia has the potential to produce sustainable palm oil without causing deforestation. In addition, palm oil and other crops provide a productive alternative for illegal crops, like coca.

Ecuador

Ecuador aims to help palm oil producers switch to sustainable methods and achieve RSPO certification under initiatives to develop greener industries.

Ghana

Ghana has a lot of palm nut species, which may become an important contributor to the agriculture of the region. Although Ghana has multiple palm species, ranging from local palm nuts to other species locally called agric, it was only marketed locally and to neighboring countries. Production is now expanding as major investment funds are purchasing plantations, because Ghana is considered a major growth area for palm oil.

Kenya

Kenya's domestic production of edible oils covers about a third of its annual demand, estimated at 380,000 metric tons (420,000 short tons). The rest is imported at a cost of around US$140 million a year, making edible oil the country's second most important import after petroleum. Since 1993 a new hybrid variety of cold-tolerant, high-yielding oil palm has been promoted by the Food and Agriculture Organization of the United Nations in western Kenya. As well as alleviating the country's deficit of edible oils while providing an important cash crop, it is claimed to have environmental benefits in the region, because it does not compete against food crops or native vegetation and it provides stabilisation for the soil.

Myanmar

Palm oil was introduced to British Burma (now Myanmar) in the 1920s. Beginning in the 1970s, smaller-scale palm oil plantations were developed in Tanintharyi Region, and Mon, Kayin, and Rakhine States. In 1999, the ruling military junta, the State Peace and Development Council, initiated the large-scale development of such plantations, especially in Tanintharyi, the southernmost region of Myanmar. As of 2019, over 401,814 ha of palm oil concessions have been awarded to 44 companies. 60% of the awarded concessions consist of forests and native vegetation, and some concessions overlap with national parks, including Tanintharyi and Lenya National Parks, which have seen deforestation and threaten conservation efforts for endemic species like the Indochinese tiger.

Social and environmental impacts

Main article: Social and environmental impact of palm oil

Forests have been cleared in parts of Indonesia and Malaysia to make space for oil-palm monoculture. This has significant impacts on the local ecosystems leading to deforestation and biodiversity loss. For example, these processes have resulted in significant acreage losses of the natural habitat of the three surviving species of orangutan. One species in particular, the Sumatran orangutan, has been listed as critically endangered because of habitat loss due to palm oil cultivation.

Social

In Borneo, the forest (F), is being replaced by oil palm plantations (G). These changes are irreversible for all practical purposes (H).

In addition to environmental concerns, palm oil development in regions that produce it has also led to significant social conflict. Regions with fast growing palm oil production have experienced significant violations of indigenous land rights, influxes of illegal immigrant labor and labor practices, and other alleged related human rights violations.

The palm oil industry has had both positive and negative impacts on workers, indigenous peoples and residents of palm oil-producing communities. Palm oil production provides employment opportunities, and has been shown to improve infrastructure, social services and reduce poverty. However, in some cases, oil palm plantations have developed lands without consultation or compensation of the indigenous people inhabiting the land, resulting in social conflict. The use of illegal immigrants in Malaysia has also raised concerns about working conditions within the palm oil industry.

Some social initiatives use palm oil cultivation as part of poverty alleviation strategies. Examples include the UN Food and Agriculture Organisation's hybrid oil palm project in Western Kenya, which improves incomes and diets of local populations, and Malaysia's Federal Land Development Authority and Federal Land Consolidation and Rehabilitation Authority, which both support rural development.

Food vs. fuel

Main article: Food vs. fuel

The use of palm oil in the production of biodiesel has led to concerns that the need for fuel is being placed ahead of the need for food, leading to malnutrition in developing nations. This is known as the food versus fuel debate. According to a 2008 report published in the Renewable and Sustainable Energy Reviews, palm oil was determined to be a sustainable source of both food and biofuel, and the production of palm oil biodiesel does not pose a threat to edible palm oil supplies. According to a 2009 study published in the Environmental Science and Policy journal, palm oil biodiesel might increase the demand for palm oil in the future, resulting in the expansion of palm oil production, and therefore an increased supply of food.

Human rights

The Palm oil industry has a history of violating labor-related human rights, indigenous territorial right and environmental rights of communities in the contexts where the industry is prominent. Child labor violations are common in smallholder farming in many of the post-colonial contexts (such as Africa) in which palm oil is produced.

One report indicated numerous allegations of human rights violations in the production of palm oil in Indonesia and Malaysia, including exposure to hazardous pesticides, child labor, and rape and sexual abuse, and unsafe carrying loads. These incidents may receive no response by the company or police, or are left unreported because victims fear retaliation from their abuser. The chemicals used in the pesticides, such as paraquat and glyphosate, have been linked to diseases such as Parkinson's disease and cancer.

Reports of Indigenous peoples and communities in Indonesia, indicate losing farmland and traditionally significant land due to palm oil industry expansion. In 2017, there were over 650 different land disputes between palm oil plantations and Indigenous land owners. Indigenous communities also expressed concern over the loss of natural resources, such as wild rubber, reed, and adat forests (communal forests). Indigenous communities have made some ground when it comes to land disputes, either through protest or legal means.

Other concerns when it comes to Indigenous communities being impacted include lack of government oversight on palm oil plantations, political corruption, or the lacking of enforcement on laws meant to protect Indigenous lands. In countries such as Guatemala, palm oil plantations have significant leverage within the local justice system, leading local police to disregard land claims, going as far as using force to break up protests, and even murdering local leaders.

Environmental

See also: 2015 Southeast Asian haze

While only 5% of the world's vegetable oil farmland is used for palm plantations, palm cultivation produces 38% of the world's total vegetable oil supply. In terms of oil yield, a palm plantation is 10 times more productive than soybean, sunflower or rapeseed cultivation because the palm fruit and kernel both provide usable oil. Palm oil has garnered criticism from environmentalists due to the environmental importance of where it is grown. However, it is indisputably more efficient in comparison to other oil-producing plants. In 2016, it was found that palm oil farms produce around 4.17 metric tons of oil per hectare. By contrast other oils, such as sunflower, soybean, or peanut only produce 0.56, 0.39, and 0.16 metric tons respectively per hectare. Palm oil is the most sustainable vegetable oil in terms of yield, requiring one-ninth of land used by other vegetable oil crops. In the future, laboratory-grown microbes might achieve higher yields per unit of land at comparable prices.

However, palm oil cultivation has been criticized for its impact on the natural environment, including deforestation, loss of natural habitats, and greenhouse gas emissions which have threatened critically endangered species, such as the orangutan and Sumatran tiger. Slash-and-burn techniques are still used to create new plantations across palm oil producing countries. From January to September 2019, 857,000 hectares of land was burned in Indonesia; peatlands accounted for more than a quarter of the burned area. The widespread deforestation and other environmental destruction in Indonesia, much of which is caused by palm oil production has often been described by academics as an ecocide.

Deforestation in Indonesia, to make way for an oil palm plantation.

Environmental groups such as Greenpeace and Friends of the Earth oppose the use of palm oil biofuels, claiming that the deforestation caused by oil palm plantations is more damaging for the climate than the benefits gained by switching to biofuel and using the palms as carbon sinks.

A 2018 study by the International Union for Conservation of Nature (IUCN) concluded that palm oil is "here to stay" due to its higher productivity compared with many other vegetable oils. The IUCN maintains that replacing palm oil with other vegetable oils would necessitate greater amounts of agricultural land, negatively affecting biodiversity. The IUCN advocates better practices in the palm oil industry, including the prevention of plantations from expanding into forested regions and creating a demand for certified and sustainable palm oil products.

In 2019, the Rainforest Action Network surveyed eight global brands involved in palm oil extraction in the Leuser Ecosystem, and said that none was performing adequately in avoiding "conflict palm oil". Many of the companies told the Guardian they were working to improve their performance. A WWF scorecard rated only 15 out of 173 companies as performing well.

In 2020 a study by Chain Reaction Research concluded that NDPE (No Deforestation, No Peat, No Exploitation) policies cover 83% of palm oil refineries. NDPE policies are according to the Chain Reaction Research the most effective private mechanism to cut the direct link with deforestation, due to the economic leverage refineries have over palm oil growers.

Markets

Palm oil is one of the most commonly produced vegetable oils

According to the Hamburg-based Oil World trade journal, in 2008 global production of oils and fats stood at 160 million tonnes. Palm oil and palm kernel oil were jointly the largest contributor, accounting for 48 million tonnes, or 30% of the total output. Soybean oil came in second with 37 million tonnes (23%). About 38% of the oils and fats produced in the world were shipped across oceans. Of the 60 million tonnes of oils and fats exported around the world, palm oil and palm kernel oil made up close to 60%; Malaysia, with 45% of the market share, dominated the palm oil trade. Production of palm oil that complies with voluntary sustainability standards is growing at a faster rate than conventional production. Standard-compliant production increased by 110% from 2008 to 2016, while conventional production increased by 2%. The production of vegetable oils as a whole went up 125% between 2000 and 2020, driven by a sharp increase in palm oil.

Food label regulations

Previously, palm oil could be listed as "vegetable fat" or "vegetable oil" on food labels in the European Union (EU). From December 2014, food packaging in the EU is no longer allowed to use the generic terms "vegetable fat" or "vegetable oil" in the ingredients list. Food producers are required to list the specific type of vegetable fat used, including palm oil. Vegetable oils and fats can be grouped together in the ingredients list under the term "vegetable oils" or "vegetable fats" but this must be followed by the type of vegetable origin (e.g., palm, sunflower, or rapeseed) and the phrase "in varying proportions".

In Malaysia, it is illegal to label products in ways that "discriminate against" palm oil. Offenders can be fined up to RM250,000 or imprisoned for up to five years.

Supply chain institutions

Consumer Goods Forum

In 2010, the Consumer Goods Forum passed a resolution that its members would reduce deforestation to net zero by 2020. They planned to do this through sustainable production of several commodities, including palm oil. As of 2023 that goal has not been met.

Roundtable on Sustainable Palm Oil (RSPO)

Roundtable No 2 (RT2) in Zürich in 2005

The Roundtable on Sustainable Palm Oil (RSPO) was established in 2004 with the objective of promoting the growth and use of sustainable palm oil products through global standards and multistakeholder governance. The seat of the association is in Zürich, Switzerland, while the secretariat is currently based in Kuala Lumpur, with a satellite office in Jakarta. RSPO currently has 5,650 members from 94 countries.

The RSPO was established following concerns raised by non-governmental organizations about environmental impacts resulting from palm oil production.

51,999,404 metric tonnes of palm oil produced in 2016 was RSPO certified. Products containing Certified Sustainable Palm Oil (CSPO) can carry the RSPO trademark. Members of the RSPO include palm oil producers, environmental groups, and manufacturers who use palm oil in their products. In 2014, Indonesia accounted for 40% of global palm oil production and 44% of the total RSPO-certified areas.

After the meeting in 2009, a number of environmental organisations were critical of the scope of the agreements reached. Palm oil growers who produce CSPO have been critical of the organization because, though they have met RSPO standards and assumed the costs associated with certification, the market demand for certified palm oil remains low. Even though deforestation has decreased in RSPO-certified oil palm plantations, peatlands continue to be drained and burned for the creation of new RSPO-certified palm plantations.

Left, reddish palm oil made from the pulp of oil palm fruit. Right, clear palm kernel oil made from the kernels

Nutrition, composition and health

Palm oil is a food staple in many cuisines, contributing significant calories as well as fat. Globally, humans consumed an average of 7.7 kg (17 lb) of palm oil per person in 2015. Although the relationship of palm oil consumption to disease risk has been previously assessed, the quality of the clinical research specifically assessing palm oil effects has been generally poor. Consequently, research has focused on the deleterious effects of palm oil and palmitic acid consumption as sources of saturated fat content in edible oils, leading to conclusions that palm oil and saturated fats should be replaced with polyunsaturated fats in the diet.

A 2015 meta-analysis and 2017 advisory from the American Heart Association indicated that palm oil is among foods supplying dietary saturated fat which increases blood levels of LDL cholesterol and increased risk of cardiovascular diseases, leading to recommendations for reduced use or elimination of dietary palm oil in favor of consuming unhydrogenated vegetable oils. A 2019 meta-analysis found no association between total fat, saturated fatty acids, monounsaturated fatty acid, and polyunsaturated fatty acid intake with risk of cardiovascular disease.

Glycidyl fatty acid esters (GE), 3-MCPD and 2-MCPD, are found especially in palm oils and palm fats because of their refining at high temperatures (approx. 200 °C (392 °F)). Since glycidol, the parent compound of GE, is considered genotoxic and carcinogenic, the EFSA did not set a safe level for GE. According to the chair of the CONTAM (EFSA's expert Panel on Contaminants in the Food Chain), "The exposure to GE of babies consuming solely infant formula is a particular concern as this is up to ten times what would be considered of low concern for public health". The EFSA's tolerable daily intake (TDI) of 3-MCPD and its fatty acid esters was set to 0.8 micrograms per kilogram of body weight per day (μg/kg bw/day) in 2016 and increased to 2 μg/kg bw/day in 2017, based on evidence linking this substance to organ damage in animal tests and on possible adverse effects on the kidney and on male fertility. According to the EFSA, there is not enough data to set a safe level for 2-MCPD. As of December 2022, the Malaysian Palm Oil Board issued an amendment to its palm oil licensing conditions to include maximum limits of 1.25 ppm and 1 ppm, respectively, to the amount of 3-MCPDE and GE that can be found in processed palm oil.

Key components

Fatty acids

Main article: Fatty acid

Palm oil, like all fats, is composed of fatty acids, esterified with glycerol. Palm oil has an especially high concentration of saturated fat, specifically the 16-carbon saturated fatty acid, palmitic acid, to which it gives its name. Monounsaturated oleic acid is also a major constituent of palm oil. Unrefined palm oil is a significant source of tocotrienol, part of the vitamin E family.

The linoleic acid content of palm oil is about 6,4 - 15%.

The approximate concentration of esterified fatty acids in palm oil is:

Fatty acid content of palm oil (present as triglyceride esters) Type of fatty acid Fraction Myristic saturated C14   1.0% Palmitic saturated C16   43.5% Stearic saturated C18   4.3% Oleic monounsaturated C18:1   36.6% Linoleic polyunsaturated C18:2   9.1% Other/unknown   5.5% black: saturated grey: monounsaturated blue: polyunsaturated

Carotenes

Red palm oil is rich in carotenes, such as alpha-carotene, beta-carotene and lycopene, which give it a characteristic dark red color. However, palm oil that has been refined, bleached and deodorized from crude palm oil (called "RBD palm oil") does not contain carotenes.

Palmitic acid

Excessive intake of palmitic acid, which makes up 44% of palm oil, increases blood levels of low-density lipoprotein (LDL) and total cholesterol, and so increases risk of cardiovascular diseases. Other reviews, the World Health Organization, and the US National Heart, Lung and Blood Institute have encouraged consumers to limit the consumption of palm oil, palmitic acid and foods high in saturated fat.

Soap

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Soap

A handmade soap bar

Two equivalent images of the chemical structure of sodium stearate, a typical ingredient found in bar soaps

The chemical structure of sodium laureth sulfate, a typical ingredient found in liquid soaps

Soap is a salt of a fatty acid used in a variety of cleansing and lubricating products. In a domestic setting, soaps are surfactants usually used for washing, bathing, and other types of housekeeping. In industrial settings, soaps are used as thickeners, components of some lubricants, and precursors to catalysts.

When used for cleaning, soap solubilizes particles and grime, which can then be separated from the article being cleaned. In hand washing, as a surfactant, when lathered with a little water, soap kills microorganisms by disorganizing their membrane lipid bilayer and denaturing their proteins. It also emulsifies oils, enabling them to be carried away by running water.

Soap is created by mixing fats and oils with a base. Humans have used soap for millennia; evidence exists for the production of soap-like materials in ancient Babylon around 2800 BC.

History

Ancient Middle East

Box for Amigo del Obrero (Worker's Friend) soap from the 20th century, part of the Museo del Objeto del Objeto collection

It is uncertain as to who was the first to invent soap. The earliest recorded evidence of the production of soap-like materials dates back to around 2800 BC in ancient Babylon. A formula for making soap was written on a Sumerian clay tablet around 2500 BC; the soap was produced by heating a mixture of oil and wood ash, the earliest recorded chemical reaction, and used for washing woolen clothing.

The Ebers papyrus (Egypt, 1550 BC) indicates the ancient Egyptians used soap as a medicine and combined animal fats or vegetable oils with a soda ash substance called trona to create their soaps. Egyptian documents mention a similar substance was used in the preparation of wool for weaving.

In the reign of Nabonidus (556–539 BC), a recipe for soap consisted of uhulu [ashes], cypress [oil] and sesame [seed oil] "for washing the stones for the servant girls".

In the Southern Levant, the ashes from barilla plants, such as species of Salsola, saltwort (Seidlitzia rosmarinus) and Anabasis, were used in soap production, known as potash. Traditionally, olive oil was used instead of animal lard throughout the Levant, which was boiled in a copper cauldron for several days. As the boiling progresses, alkali ashes and smaller quantities of quicklime are added and constantly stirred. In the case of lard, it required constant stirring while kept lukewarm until it began to trace. Once it began to thicken, the brew was poured into a mold and left to cool and harden for two weeks. After hardening, it was cut into smaller cakes. Aromatic herbs were often added to the rendered soap to impart their fragrance, such as yarrow leaves, lavender, germander, etc.

Roman Empire

Pliny the Elder, whose writings chronicle life in the first century AD, describes soap as "an invention of the Gauls". The word sapo, Latin for soap, likely was borrowed from an early Germanic language and is cognate with Latin sebum, "tallow". It first appears in Pliny the Elder's account, Historia Naturalis, which discusses the manufacture of soap from tallow and ashes. There he mentions its use in the treatment of scrofulous sores, as well as among the Gauls as a dye to redden hair which the men in Germania were more likely to use than women. The Romans avoided washing with harsh soaps before encountering the milder soaps used by the Gauls around 58 BC. Aretaeus of Cappadocia, writing in the 2nd century AD, observes among "Celts, which are men called Gauls, those alkaline substances that are made into balls [...] called soap". The Romans' preferred method of cleaning the body was to massage oil into the skin and then scrape away both the oil and any dirt with a strigil. The standard design is a curved blade with a handle, all of which is made of metal.

The 2nd-century AD physician Galen describes soap-making using lye and prescribes washing to carry away impurities from the body and clothes. The use of soap for personal cleanliness became increasingly common in this period. According to Galen, the best soaps were Germanic, and soaps from Gaul were second best. Zosimos of Panopolis, circa 300 AD, describes soap and soapmaking.

Ancient China

A detergent similar to soap was manufactured in ancient China from the seeds of Gleditsia sinensis. Another traditional detergent is a mixture of pig pancreas and plant ash called zhuyizi (simplified Chinese: 猪胰子; traditional Chinese: 豬胰子; pinyin: zhūyízǐ). Soap made of animal fat did not appear in China until the modern era. Soap-like detergents were not as popular as ointments and creams.

Islamic Golden Age

Hard toilet soap with a pleasant smell was produced in the Middle East during the Islamic Golden Age, when soap-making became an established industry. Recipes for soap-making are described by Muhammad ibn Zakariya al-Razi (c. 865–925), who also gave a recipe for producing glycerine from olive oil. In the Middle East, soap was produced from the interaction of fatty oils and fats with alkali. In Syria, soap was produced using olive oil together with alkali and lime. Soap was exported from Syria to other parts of the Muslim world and to Europe.

A 12th-century document describes the process of soap production. It mentions the key ingredient, alkali, which later became crucial to modern chemistry, derived from al-qaly or "ashes".

By the 13th century, the manufacture of soap in the Middle East had become a major cottage industry, with sources in Nablus, Fes, Damascus, and Aleppo.

Medieval Europe

Marseille soap in blocks of 600 g

Soapmakers in Naples were members of a guild in the late sixth century (then under the control of the Eastern Roman Empire), and in the eighth century, soap-making was well known in Italy and Spain. The Carolingian capitulary De Villis, dating to around 800, representing the royal will of Charlemagne, mentions soap as being one of the products the stewards of royal estates are to tally. The lands of Medieval Spain were a leading soapmaker by 800, and soapmaking began in the Kingdom of England about 1200. Soapmaking is mentioned both as "women's work" and as the produce of "good workmen" alongside other necessities, such as the produce of carpenters, blacksmiths, and bakers.

In Europe, soap in the 9th century was produced from animal fats and had an unpleasant smell. This changed when olive oil began to be used in soap formulas instead, after which much of Europe's soap production moved to the Mediterranean olive-growing regions. Hard toilet soap was introduced to Europe by Arabs and gradually spread as a luxury item. It was often perfumed. By the 15th century, the manufacture of soap in the Christendom had become virtually industrialized, with sources in Antwerp, Castile, Marseille, Naples and Venice.

16th–17th century

In France, by the second half of the 16th century, the semi-industrialized professional manufacture of soap was concentrated in a few centers of Provence—Toulon, Hyères, and Marseille—which supplied the rest of France. In Marseilles, by 1525, production was concentrated in at least two factories, and soap production at Marseille tended to eclipse the other Provençal centers. English manufacture tended to concentrate in London.

Finer soaps were later produced in Europe from the 17th century, using vegetable oils (such as olive oil) as opposed to animal fats. Many of these soaps are still produced, both industrially and by small-scale artisans. Castile soap is a popular example of the vegetable-only soaps derived from the oldest "white soap" of Italy. In 1634 Charles I granted the newly formed Society of Soapmakers a monopoly in soap production who produced certificates from 'foure Countesses, and five Viscountesses, and divers other Ladies and Gentlewomen of great credite and quality, besides common Laundresses and others', testifying that 'the New White Soap washeth whiter and sweeter than the Old Soap'.

During the Restoration era (February 1665 – August 1714) a soap tax was introduced in England, which meant that until the mid-1800s, soap was a luxury, used regularly only by the well-to-do. The soap manufacturing process was closely supervised by revenue officials who made sure that soapmakers' equipment was kept under lock and key when not being supervised. Moreover, soap could not be produced by small makers because of a law that stipulated that soap boilers must manufacture a minimum quantity of one imperial ton at each boiling, which placed the process beyond the reach of the average person. The soap trade was boosted and deregulated when the tax was repealed in 1853.

Modern period

Industrially manufactured bar soaps became available in the late 18th century, as advertising campaigns in Europe and America promoted popular awareness of the relationship between cleanliness and health. In modern times, the use of soap has become commonplace in industrialized nations due to a better understanding of the role of hygiene in reducing the population size of pathogenic microorganisms.

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  Advertising for Dobbins' medicated toilet soap
   
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  A 1922 magazine advertisement for Palmolive Soap
   
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  Liquid soap

Caricature of Lillie Langtry, from Punch, Christmas 1890: The soap box on which she sits reflects her endorsements of cosmetics and soaps.

Until the Industrial Revolution, soapmaking was conducted on a small scale and the product was rough. In 1780, James Keir established a chemical works at Tipton, for the manufacture of alkali from the sulfates of potash and soda, to which he afterwards added a soap manufactory. The method of extraction proceeded on a discovery of Keir's. In 1790, Nicolas Leblanc discovered how to make alkali from common salt. Andrew Pears started making a high-quality, transparent soap, Pears soap, in 1807 in London. His son-in-law, Thomas J. Barratt, became the brand manager (the first of its kind) for Pears in 1865. In 1882, Barratt recruited English actress and socialite Lillie Langtry to become the poster-girl for Pears soap, making her the first celebrity to endorse a commercial product.

William Gossage produced low-priced, good-quality soap from the 1850s. Robert Spear Hudson began manufacturing a soap powder in 1837, initially by grinding the soap with a mortar and pestle. American manufacturer Benjamin T. Babbitt introduced marketing innovations that included the sale of bar soap and distribution of product samples. William Hesketh Lever and his brother, James, bought a small soap works in Warrington in 1886 and founded what is still one of the largest soap businesses, formerly called Lever Brothers and now called Unilever. These soap businesses were among the first to employ large-scale advertising campaigns.

Liquid soap

See also: Detergent

A soap dispenser

Liquid soap was not invented until the nineteenth century; in 1865, William Sheppard patented a liquid version of soap. In 1898, B.J. Johnson developed a soap derived from palm and olive oils; his company, the B.J. Johnson Soap Company, introduced "Palmolive" brand soap that same year. This new brand of soap became popular rapidly, and to such a degree that B.J. Johnson Soap Company changed its name to Palmolive.

In the early 1900s, other companies began to develop their own liquid soaps. Such products as Pine-Sol and Tide appeared on the market, making the process of cleaning things other than skin, such as clothing, floors, and bathrooms, much easier.

Liquid soap also works better for more traditional or non-machine washing methods, such as using a washboard.

Types

A collection of decorative bar soaps, as often found in hotels

Since they are salts of fatty acids, soaps have the general formula (RCO₂⁻)_nMⁿ⁺, where R is an alkyl, M is a metal and n is the charge of the cation. The major classification of soaps is determined by the identity of Mⁿ⁺. When M is Na (sodium) or K (potassium), the soaps are called toilet soaps, used for handwashing. Many metal dications (Mg²⁺, Ca²⁺, and others) give metallic soap. When M is Li, the result is lithium soap (e.g., lithium stearate), which is used in high-performance greases. A cation from an organic base such as ammonium can be used instead of a metal; ammonium nonanoate is an ammonium-based soap that is used as an herbicide.

When used in hard water, soap does not lather well and a scum of stearate, a common ingredient in soap, forms as an insoluble precipitate.

Non-toilet soaps

Soaps are key components of most lubricating greases and thickeners. Greases are usually emulsions of calcium soap or lithium soap and mineral oil. Many other metallic soaps are also useful, including those of aluminium, sodium, and mixtures thereof. Such soaps are also used as thickeners to increase the viscosity of oils. In ancient times, lubricating greases were made by the addition of lime to olive oil.

Metal soaps are also included in modern artists' oil paints formulations as a rheology modifier.

Production of metallic soaps

Most metal soaps are prepared by hydrolysis:

2 RCO₂H + CaO → (RCO₂)₂Ca + H₂O

Toilet soaps

In a domestic setting, "soap" usually refers to what is technically called a toilet soap, used for household and personal cleaning. When used for cleaning, soap solubilizes particles and fats/oils, which can then be separated from the article being cleaned. The insoluble oil/fat molecules become associated inside micelles, tiny spheres formed from soap molecules with polar hydrophilic (water-attracting) groups on the outside and encasing a lipophilic (fat-attracting) pocket, which shields the oil/fat molecules from the water making them soluble. Anything that is soluble will be washed away with the water.

Structure of a micelle, a cell-like structure formed by the aggregation of soap subunits (such as sodium stearate): The exterior of the micelle is hydrophilic (attracted to water) and the interior is lipophilic (attracted to oils).

Production of toilet soaps

The production of toilet soaps usually entails saponification of triglycerides, which are vegetable or animal oils and fats. An alkaline solution (often lye or sodium hydroxide) induces saponification whereby the triglyceride fats first hydrolyze into salts of fatty acids. Glycerol (glycerin) is liberated. The glycerin can remain in the soap product as a softening agent, although it is sometimes separated.

The type of alkali metal used determines the kind of soap product. Sodium soaps, prepared from sodium hydroxide, are firm, whereas potassium soaps, derived from potassium hydroxide, are softer or often liquid. Historically, potassium hydroxide was extracted from the ashes of bracken or other plants. Lithium soaps also tend to be hard. These are used exclusively in greases.

For making toilet soaps, triglycerides (oils and fats) are derived from coconut, olive, or palm oils, as well as tallow. Triglyceride is the chemical name for the triesters of fatty acids and glycerin. Tallow, i.e., rendered fat, is the most available triglyceride from animals. Each species offers quite different fatty acid content, resulting in soaps of distinct feel. The seed oils give softer but milder soaps. Soap made from pure olive oil, sometimes called Castile soap or Marseille soap, is reputed for its particular mildness. The term "Castile" is also sometimes applied to soaps from a mixture of oils with a high percentage of olive oil.

Fatty acid content of various fats used for soapmaking

	Lauric acid	Myristic acid	Palmitic acid	Stearic acid	Oleic acid	Linoleic acid	Linolenic acid
fats	C12 saturated	C14 saturated	C16 saturated	C18 saturated	C18 monounsaturated	C18 diunsaturated	C18 triunsaturated
Tallow	0	4	28	23	35	2	1
Coconut oil	48	18	9	3	7	2	0
Palm kernel oil	46	16	8	3	12	2	0
Palm oil	0	1	44	4	37	9	0
Laurel oil	54	0	0	0	15	17	0
Olive oil	0	0	11	2	78	10	0
Canola oil	0	1	3	2	58	9	23

Soap-making for hobbyists

Manufacturing process of soaps/detergents

A variety of methods are available for hobbyists to make soap. Most soapmakers use processes where the glycerol remains in the product, and the saponification continues for many days after the soap is poured into molds. The glycerol is left during the hot process method, but at the high temperature employed, the reaction is practically completed in the kettle, before the soap is poured into molds. This simple and quick process is employed in small factories all over the world.

Handmade soap from the cold process also differs from industrially made soap in that an excess of fat or (Coconut Oil, Cazumbal Process) are used, beyond that needed to consume the alkali (in a cold-pour process, this excess fat is called "superfatting"), and the glycerol left in acts as a moisturizing agent. However, the glycerine also makes the soap softer. The addition of glycerol and processing of this soap produces glycerin soap. Superfatted soap is more skin-friendly than one without extra fat, although it can leave a "greasy" feel. Sometimes, an emollient is added, such as jojoba oil or shea butter. Sand or pumice may be added to produce a scouring soap. The scouring agents serve to remove dead cells from the skin surface being cleaned. This process is called exfoliation.

To make antibacterial soap, compounds such as triclosan or triclocarban can be added. There is some concern that use of antibacterial soaps and other products might encourage antimicrobial resistance in microorganisms.

Desertification

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Desertification

Global distribution of dryland subtypes based on the aridity index computed over a 30-year average during 1981 to 2010. Typical deserts are indicated by the hyper-arid category (light yellow)

Desertification is a type of gradual land degradation of fertile land into arid desert due to a combination of natural processes and human activities. This spread of arid areas is caused by a variety of factors, such as overexploitation of soil as a result of human activity and the effects of climate change. Geographic areas most affected are located in Africa (Sahel region), Asia (Gobi Desert and Mongolia) and parts of South America. Drylands occupy approximately 40–41% of Earth's land area and are home to more than 2 billion people. Effects of desertification include sand and dust storms, food insecurity, and poverty.

Humans can fight desertification in various ways. For instance, improving soil quality, greening deserts, managing grazing better, and planting trees (reforestation and afforestation) can all help reverse desertification.

Throughout geological history, the development of deserts has occurred naturally over long intervals of time. The modern study of desertification emerged from the study of the 1980s drought in the Sahel.

Definitions

As recently as 2005, considerable controversy existed over the proper definition of the term "desertification." Helmut Geist (2005) identified more than 100 formal definitions. The most widely accepted of these was that of the Princeton University Dictionary which defined it as "the process of fertile land transforming into desert typically as a result of deforestation, drought or improper/inappropriate agriculture". This definition clearly demonstrated the interconnectedness of desertification and human activities, in particular land use and land management practices. It also highlighted the economic, social and environmental implications of desertification.

However, this original understanding that desertification involved the physical expansion of deserts has been rejected as the concept has further evolved since then. Desertification has been defined in the text of the United Nations Convention to Combat Desertification (UNCCD) as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities," according to Hulme and Kelly (1993).

There exists also controversy around the sub-grouping of types of desertification, including, for example, the validity and usefulness of such terms as "man-made desert" and "non-pattern desert".

Causes

See also: Deforestation § Causes

 

Preventing man-made overgrazing

Goats inside of a pen in Norte Chico, Chile. Overgrazing of drylands by poorly managed traditional herding is one of the primary causes of desertification.

 

Wildebeest in Masai Mara during the Great Migration. Overgrazing is not necessarily caused by nomadic grazers in large travelling herd populations.

Immediate causes

The immediate cause of desertification is the loss of most vegetation. This is driven by a number of factors, alone or in combination, such as drought, climatic shifts, tillage for agriculture, overgrazing and deforestation for fuel or construction materials. Though vegetation plays a major role in determining the biological composition of the soil, studies have shown that, in many environments, the rate of erosion and runoff decreases exponentially with increased vegetation cover. Unprotected, dry soil surfaces blow away with the wind or are washed away by flash floods, leaving infertile lower soil layers that bake in the sun and become an unproductive hardpan.

Influence of human activities

Early studies argued one of the most common causes of desertification was overgrazing, over consumption of vegetation by cattle or other livestock. However, the role of local overexploitation in driving desertification in the recent past is controversial. Drought in the Sahel region is now thought to be principally the result of seasonal variability in rainfall caused by large-scale sea surface temperature variations, largely driven by natural variability and anthropogenic emissions of aerosols (reflective sulphate particles) and greenhouse gases. As a result, changing ocean temperature and reductions in sulfate emissions have caused a re-greening of the region. This has led some scholars to argue that agriculture-induced vegetation loss is a minor factor in desertification.

A shepherd guiding his sheep through the high desert outside Marrakech, Morocco

Human population dynamics have a considerable impact on overgrazing, over-farming and deforestation, as previously acceptable techniques have become unsustainable.

There are multiple reasons farmers use intensive farming as opposed to extensive farming but the main reason is to maximize yields. By increasing productivity, they require a lot more fertilizer, pesticides, and labor to upkeep machinery. This continuous use of the land rapidly depletes the nutrients of the soil causing desertification to spread.

Natural variations

Scientists agree that the existence of a desert in the place where the Sahara desert is now located is due to natural variations in solar insolation due to orbital precession of the Earth. Such variations influence the strength of the West African Monsoon, inducing feedback in vegetation and dust emission that amplify the cycle of wet and dry Sahara climate. There is also a suggestion the transition of the Sahara from savanna to desert during the mid-Holocene was partially due to overgrazing by the cattle of the local population.

Climate change

See also: Effects of climate change on the water cycle and Effects of climate change on biomes

Research into desertification is complex, and there is no single metric which can define all aspects. However, more intense climate change is still expected to increase the current extent of drylands on the Earth's continents: from 38% in late 20th century to 50% or 56% by the end of the century, under the "moderate" and high-warming Representative Concentration Pathways 4.5 and 8.5. Most of the expansion will be seen over regions such as "southwest North America, the northern fringe of Africa, southern Africa, and Australia".

Drylands cover 41% of the earth’s land surface and include 45% of the world’s agricultural land. These regions are among the most vulnerable ecosystems to anthropogenic climate and land use change and are under threat of desertification. An observation-based attribution study of desertification was carried out in 2020 which accounted for climate change, climate variability, CO₂ fertilization as well as both the gradual and rapid ecosystem changes caused by land use. The study found that, between 1982 and 2015, 6% of the world’s drylands underwent desertification driven by unsustainable land use practices compounded by anthropogenic climate change. Despite an average global greening, anthropogenic climate change has degraded 12.6% (5.43 million km²) of drylands, contributing to desertification and affecting 213 million people, 93% of who live in developing economies.

Effects

Sand and dust storms

View of Sydney Harbour Bridge covered in dust

There has been a 25% increase in global annual dust emissions between the late nineteenth century to present day. The increase of desertification has also increased the amount of loose sand and dust that the wind can pick up ultimately resulting in a storm. For example, dust storms in the Middle East “are becoming more frequent and intense in recent years” because “long-term reductions in rainfall [cause] lower soil moisture and vegetative cover”.

Dust storms can contribute to certain respiratory disorders such as pneumonia, skin irritations, asthma and many more. They can pollute open water, reduce the effectiveness of clean energy efforts, and halt most forms of transportation.

Dust and sand storms can have a negative effect on the climate which can make desertification worse. Dust particles in the air scatter incoming radiation from the sun (Hassan, 2012). The dust can provide momentary coverage for the ground temperature but the atmospheric temperature will increase. This can disform and shorten the life time of clouds which can result in less rainfall.

Food insecurity

Global food security is being threatened by desertification. The more that population grows, the more food that has to be grown. The agricultural business is being displaced from one country to another. For example, Europe on average imports over 50% of its food. Meanwhile, 44% of agricultural land is located in dry lands and it supplies 60% of the world's food production. Desertification is decreasing the amount of sustainable land for agricultural uses but demands are continuously growing. In the near future, the demands will overcome the supply. The violent herder–farmer conflicts in Nigeria, Sudan, Mali and other countries in the Sahel region have been exacerbated by climate change, land degradation and population growth.

Increasing poverty

Wind erosion outside Leuchars

At least 90% of the inhabitants of drylands live in developing countries, where they also suffer from poor economic and social conditions. This situation is exacerbated by land degradation because of the reduction in productivity, the precariousness of living conditions and the difficulty of access to resources and opportunities.

Many underdeveloped countries are affected by overgrazing, land exhaustion and overdrafting of groundwater due to pressures to exploit marginal drylands for farming. Decision-makers are understandably averse to invest in arid zones with low potential. This absence of investment contributes to the marginalization of these zones. When unfavorable agri-climatic conditions are combined with an absence of infrastructure and access to markets, as well as poorly adapted production techniques and an underfed and undereducated population, most such zones are excluded from development.

Desertification often causes rural lands to become unable to support the same sized populations that previously lived there. This results in mass migrations out of rural areas and into urban areas particularly in Africa creating unemployment and slums. The number of these environmental refugees grows every year, with projections for sub-Saharan Africa showing a probable increase from 14 million in 2010 to nearly 200 million by 2050. This presents a future crisis for the region, as neighboring nations do not always have the ability to support large populations of refugees.

In Mongolia, the land is 90% fragile dry land, which causes many herders to migrate to the city for work. With very limited resources, the herders that stay on the dry land graze very carefully in order to preserve the land.

Agriculture is a main source of income for many desert communities. The increase in desertification in these regions has degraded the land to such an extent where people can no longer productively farm and make a profit. This has negatively impacted the economy and increased poverty rates.

There is, however, increased global advocacy e.g. the UN SDG 15 to combat desertification and restore affected lands.

Geographic areas affected

Drylands occupy approximately 40–41% of Earth's land area and are home to more than 2 billion people. It has been estimated that some 10–20% of drylands are already degraded, the total area affected by desertification being between 6 and 12 million square kilometers, that about 1–6% of the inhabitants of drylands live in desertified areas, and that a billion people are under threat from further desertification.

Sahel

Further information: Sahel § Desertification and soil loss

The impact of climate change and human activities on desertification are exemplified in the Sahel region of Africa. The region is characterized by a dry hot climate, high temperatures and low rainfall (100–600 mm per year). So, droughts are the rule in the Sahel region. The Sahel has lost approximately 650,000 km² of its productive agricultural land over the past 50 years; the propagation of desertification in this area is considerable.

Sahel region of Mali

The climate of the Sahara has undergone enormous variations over the last few hundred thousand years, oscillating between wet (grassland) and dry (desert) every 20,000 years (a phenomenon believed to be caused by long-term changes in the North African climate cycle that alters the path of the North African Monsoon, caused by an approximately 40,000-year cycle in which the axial tilt of the earth changes between 22° and 24.5°). Some statistics have shown that, since 1900, the Sahara has expanded by 250 km to the south over a stretch of land from west to east 6,000 km long.

Lake Chad, located in the Sahel region, has undergone desiccation due to water withdrawal for irrigation and decrease in rainfall. The lake has shrunk by over 90% since 1987, displacing millions of inhabitants. Recent efforts have managed to make some progress toward its restoration, but it is still considered to be at risk of disappearing entirely.

To limit desertification, the Great Green Wall (Africa) initiative was started in 2007 involving the planting of vegetation along a stretch of 7,775 km, 15 km wide, involving 22 countries to 2030. The purpose of this mammoth planting initiative is to enhance retention of water in the ground following the seasonal rainfall, thus promoting land rehabilitation and future agriculture. Senegal has already contributed to the project by planting 50,000 acres of trees. It is said to have improved land quality and caused an increase in economic opportunity in the region.

Gobi Desert and Mongolia

See also: Environmental issues in Mongolia § Desertification

Another major area that is being impacted by desertification is the Gobi Desert located in Northern China and Southern Mongolia. The Gobi Desert is the fastest expanding desert on Earth, as it transforms over 3,600 square kilometres (1,400 square miles) of grassland into wasteland annually. Although the Gobi Desert itself is still a distance away from Beijing, reports from field studies state there are large sand dunes forming only 70 km (43.5 mi) outside the city.

In Mongolia, around 90% of grassland is considered vulnerable to desertification by the UN. An estimated 13% of desertification in Mongolia is caused by natural factors; the rest is due to human influence particularly overgrazing and increased erosion of soils in cultivated areas. During the period 1940 to 2015, the mean air temperature increased by 2.24 °C.^[67] The warmest ten-year period was during the latest decade to 2021. Precipitation has decreased by 7% over this period resulting in increased arid conditions throughout Mongolia. The Gobi desert continues to expand northward, with over 70% of Mongolia's land degraded through overgrazing, deforestation, and climate change. In addition, the Mongolia government has listed forest fires, blights, unsustainable forestry and mining activities as leading causes of desertification in the country. The transition from sheep to goat farming in order to meet export demands for cashmere wool has caused degradation of grazing lands. Compared to sheep, goats do more damage to grazing lands by eating roots and flowers.

The Gobi Desert is expanding through desertification, most rapidly on the southern edge into China, which is seeing 3,600 km² (1,390 sq mi) of grassland overtaken every year. Dust storms increased in frequency between 1996 and 2016, causing further damage to China's agriculture economy. However, in some areas desertification has been slowed or reversed.

The northern and eastern boundaries between desert and grassland are constantly changing. This is mostly due to the climate conditions before the growing season, which influence the rate of evapotranspiration and subsequent plant growth.

The expansion of the Gobi is attributed mostly to human activities, locally driven by deforestation, overgrazing, and depletion of water resources, as well as to climate change.

China has tried various plans to slow the expansion of the desert, which have met with some success. The Three-North Shelter Forest Program (or "Green Great Wall") is a Chinese government tree-planting project begun in 1978 and set to continue through 2050. The goal of the program is to reverse desertification by planting aspen and other fast-growing trees on some 36.5 million hectares across some 551 counties in 12 provinces of northern China.

South America

South America is another area vulnerable by desertification, as 25% of the land is classified as drylands and over 68% of the land area has undergone soil erosion as a result of deforestation and overgrazing. 27 to 43% of the land areas in Bolivia, Chile, Ecuador and Peru are at risk due to desertification. In Argentina, Mexico and Paraguay, greater than half the land area is degraded by desertification and cannot be used for agriculture. In Central America, drought has caused increased unemployment and decreased food security - also causing migration of people. Similar impacts have been seen in rural parts of Mexico where about 1,000 km² of land have been lost yearly due to desertification. In Argentina, desertification has the potential to disrupt the nation's food supply.

Reversing desertification

See also: Deforestation § Control

A 2018 meeting in New Delhi related to the United Nations Convention to Combat Desertification

Anti-sand shields in north Sahara, Tunisia

Jojoba plantations, such as those shown, have played a role in combating edge effects of desertification in the Thar Desert, India.

Saxaul planted along roads in Xinjiang near Cherchen to slow desertification

Techniques and countermeasures exist for mitigating or reversing desertification. For some of these measures, there are numerous barriers to their implementation. Yet for others, the solution simply requires the exercise of human reason.

One proposed barrier is that the costs of adopting sustainable agricultural practices sometimes exceed the benefits for individual farmers, even while they are socially and environmentally beneficial. Another issue is a lack of political will, and lack of funding to support land reclamation and anti-desertification programs.

Desertification is recognized as a major threat to biodiversity. Some countries have developed biodiversity action plans to counter its effects, particularly in relation to the protection of endangered flora and fauna.

Improving soil quality

Main article: Soil regeneration

Techniques focus on two aspects: provisioning of water, and fixation and hyper-fertilizing soil. Fixating the soil is often done through the use of shelter belts, woodlots and windbreaks. Windbreaks are made from trees and bushes and are used to reduce soil erosion and evapotranspiration. They were widely encouraged by development agencies from the middle of the 1980s in the Sahel area of Africa.

Some soils (for example, clay), due to lack of water can become consolidated rather than porous (as in the case of sandy soils). Some techniques as zaï or tillage are then used to still allow the planting of crops.

Another technique that is useful is contour trenching. This involves the digging of 150 m long, 1 m deep trenches in the soil. The trenches are made parallel to the height lines of the landscape, preventing the water from flowing within the trenches and causing erosion. Stone walls are placed around the trenches to prevent the trenches from closing up again. This method was invented by Peter Westerveld.

Enriching of the soil and restoration of its fertility is often achieved by plants. Of these, leguminous plants which extract nitrogen from the air and fix it in the soil, succulents (such as Opuntia), and food crops/trees as grains, barley, beans and dates are the most important. Sand fences can also be used to control drifting of soil and sand erosion.

Another way to restore soil fertility is through the use of nitrogen-rich fertilizer. Due to the higher cost of this fertilizer, many smallholder farmers are reluctant to use it, especially in areas where subsistence farming is common. Several nations, including India, Zambia, and Malawi have responded to this by implementing subsidies to help encourage adoption of this technique.

Some research centres (such as Bel-Air Research Center IRD/ISRA/UCAD) are also experimenting with the inoculation of tree species with mycorrhiza in arid zones. The mycorrhiza are basically fungi attaching themselves to the roots of the plants. They hereby create a symbiotic relation with the trees, increasing the surface area of the tree's roots greatly (allowing the tree to gather much more nutrient from the soil).

The bioengineering of soil microbes, particularly photosynthesizers, has also been suggested and theoretically modeled as a method to protect drylands. The aim would be to enhance the existing cooperative loops between soil microbes and vegetation.

Desert greening

Main article: Desert greening

As there are many different types of deserts, there are also different types of desert reclamation methodologies. An example for this is the salt flats in the Rub' al Khali desert in Saudi Arabia. These salt flats are one of the most promising desert areas for seawater agriculture and could be revitalized without the use of freshwater or much energy.

Farmer-managed natural regeneration (FMNR) is another technique that has produced successful results for desert reclamation. Since 1980, this method to reforest degraded landscape has been applied with some success in Niger. This simple and low-cost method has enabled farmers to regenerate some 30,000 square kilometers in Niger. The process involves enabling native sprouting tree growth through selective pruning of shrub shoots. The residue from pruned trees can be used to provide mulching for fields thus increasing soil water retention and reducing evaporation. Additionally, properly spaced and pruned trees can increase crop yields. The Humbo Assisted Regeneration Project which uses FMNR techniques in Ethiopia has received money from The World Bank's BioCarbon Fund, which supports projects that sequester or conserve carbon in forests or agricultural ecosystems.

Better managed grazing

Restored grasslands store CO₂ from the atmosphere as organic plant material. Grazing livestock, usually not left to wander, consume the grass and minimize its growth. A method proposed to restore grasslands uses fences with many small paddocks, moving herds from one paddock to another after a day or two in order to mimic natural grazers and allowing the grass to grow optimally. Proponents of managed grazing methods estimate that increasing this method could increase carbon content of the soils in the world's 3.5 billion hectares of agricultural grassland and offset nearly 12 years of CO₂ emissions.

Planting trees

Main articles: Reforestation and Afforestation

Reforestation gets at one of the root causes of desertification and is not just a treatment of the symptoms. Environmental organizations work in places where deforestation and desertification are contributing to extreme poverty. There they focus primarily on educating the local population about the dangers of deforestation and sometimes employ them to grow seedlings, which they transfer to severely deforested areas during the rainy season. The Food and Agriculture Organization of the United Nations launched the FAO Drylands Restoration Initiative in 2012 to draw together knowledge and experience on dryland restoration. In 2015, FAO published global guidelines for the restoration of degraded forests and landscapes in drylands, in collaboration with the Turkish Ministry of Forestry and Water Affairs and the Turkish Cooperation and Coordination Agency.

The "Green Wall of China" is a high-profile example of one method that has been finding success in this battle with desertification. This wall is a much larger-scale version of what American farmers did in the 1930s to stop the great Midwest dust bowl. This plan was proposed in the late 1970s, and has become a major ecological engineering project that is not predicted to end until the year 2055. According to Chinese reports, there have been nearly 66 billion trees planted in China's great green wall. The green wall of China has decreased desert land in China by an annual average of 1,980 square km. The frequency of sandstorms nationwide have fallen 20% due to the green wall. Due to the success that China has been finding in stopping the spread of desertification, plans are currently being made in Africa to start a "wall" along the borders of the Sahara desert as well to be financed by the United Nations Global Environment Facility trust.

The Great Green Wall, participating countries and Sahel. In September 2020, it was reported that the GGW had covered only 4% of the planned area.

In 2007 the African Union started the Great Green Wall of Africa project in order to combat desertification in 20 countries. The wall is 8,000 km wide, stretching across the entire width of the continent and has 8 billion dollars in support of the project. The project has restored 36 million hectares of land, and by 2030 the initiative plans to restore a total of 100 million hectares. The Great Green Wall has created many job opportunities for the participating countries, with over 20,000 jobs created in Nigeria alone.

History

Further information: Historic desertification

The world's most noted deserts have been formed by natural processes interacting over long intervals of time. During most of these times, deserts have grown and shrunk independently of human activities. Paleodeserts are large sand seas now inactive because they are stabilized by vegetation, some extending beyond the present margins of core deserts, such as the Sahara, the largest hot desert.

Historical evidence shows that the serious and extensive land deterioration occurring several centuries ago in arid regions had three centers: the Mediterranean, the Mesopotamian Valley, and the Loess Plateau of China, where population was dense.

The earliest known discussion of the topic arose soon after the French colonization of West Africa, when the Comité d'Etudes commissioned a study on desséchement progressif to explore the prehistoric expansion of the Sahara Desert. The modern study of desertification emerged from the study of the 1980s drought in the Sahel.