The Doig Formation is a geologic formation of middle Triassic age in the Western Canadian Sedimentary Basin . It takes the name from Doig River , a tributary of the Beatton River , and was first described in the Texaco N.F.A. Buick Creek No. 7 well (located north-west of Fort St. John , east of the Alaska Highway ) by J.H. Armitage in 1962. .
82-574: The Doig Formation is composed of fine grained, grey argillaceous siltstone and dark calcareous shale . Phosphate nodules occur at the base of the formation. Anomalously thicker, porous sandstone channels and bars are present locally in the upper units of the formation. The formation has provided fossils of various species of conodonts ; Magnigondolella alexanderi , M. cyri , M. julii , M. nebuchadnezzari , M. salomae , Neogondolella curva , N. hastata , N. panlaurentia and N. ex gr. shoshonensis . The Doig Formation reaches
164-741: A dolomitic bed and a chert and quartz conglomerate bed. To the west it is overlain by younger Jurassic beds. It conformably overlies the Montney Formation and the contact is marked by a phosphate pellet bed in the base of the Doig. The formation correlates with the lower Llama Member of the Sulphur Mountain Formation in the southern ranges of the Canadian Rockies , with the Whistler Member of
246-810: A lord of the manor with a Roman Catholic church and priest. Thanks to the exchange with the Al-Andalus where the Arab Agricultural Revolution was underway, European agriculture transformed, with improved techniques and the diffusion of crop plants, including the introduction of sugar, rice, cotton and fruit trees (such as the orange). After 1492, the Columbian exchange brought New World crops such as maize, potatoes, tomatoes, sweet potatoes , and manioc to Europe, and Old World crops such as wheat, barley, rice, and turnips , and livestock (including horses, cattle, sheep and goats) to
328-470: A combination of labor supply and labor demand trends have driven down the share of population employed in agriculture. During the 16th century in Europe, between 55 and 75% of the population was engaged in agriculture; by the 19th century, this had dropped to between 35 and 65%. In the same countries today, the figure is less than 10%. At the start of the 21st century, some one billion people, or over 1/3 of
410-664: A hazardous industry, and farmers worldwide remain at high risk of work-related injuries, lung disease, noise-induced hearing loss , skin diseases, as well as certain cancers related to chemical use and prolonged sun exposure. On industrialized farms , injuries frequently involve the use of agricultural machinery , and a common cause of fatal agricultural injuries in developed countries is tractor rollovers . Pesticides and other chemicals used in farming can be hazardous to worker health , and workers exposed to pesticides may experience illness or have children with birth defects. As an industry in which families commonly share in work and live on
492-479: A hexagonal array in two dimensions. The fourth oxygen ion is not shared with another tetrahedron and all of the tetrahedra "point" in the same direction; i.e. all of the unshared oxygen ions are on the same side of the sheet. These unshared oxygen ions are called apical oxygen ions. In clays, the tetrahedral sheets are always bonded to octahedral sheets formed from small cations, such as aluminum or magnesium, and coordinated by six oxygen atoms. The unshared vertex from
574-444: A high use of inputs (water, fertilizer, pesticide and automation). It is practiced mainly in developed countries. From the twentieth century onwards, intensive agriculture increased crop productivity. It substituted synthetic fertilizers and pesticides for labor, but caused increased water pollution, and often involved farm subsidies. Soil degradation and diseases such as stem rust are major concerns globally; approximately 40% of
656-613: A maximum thickness of 190 metres (620 ft) in the Canadian Rockies foothills it thins towards the north and east. It occurs in the subsurface in north-western Alberta , north-eastern British Columbia and southern Yukon , from 53°N and 118°W to the Canadian Rockies. The Doig Formation is unconformably overlain by the Halfway Formation of the Schooler Creek Group ; the contact is marked by
738-400: A net negative charge and may be bonded together either by individual cations (such as potassium in illite or sodium or calcium in smectites) or by positively charged octahedral sheets (as in chlorites ). Clay minerals include the following groups: Mixed layer clay variations exist for most of the above groups. Ordering is described as a random or regular order and is further described by
820-447: A positive note, the gender gap in access to mobile internet in low- and middle-income countries fell from 25 percent to 16 percent between 2017 and 2021, and the gender gap in access to bank accounts narrowed from 9 to 6 percentage points. Women are as likely as men to adopt new technologies when the necessary enabling factors are put in place and they have equal access to complementary resources. Agriculture, specifically farming, remains
902-560: A significant component. For example, argillaceous limestones are limestones consisting predominantly of calcium carbonate , but including 10-40% of clay minerals: such limestones, when soft, are often called marls . Similarly, argillaceous sandstones such as greywacke , are sandstones consisting primarily of quartz grains, with the interstitial spaces filled with clay minerals. Agriculture Agriculture encompasses crop and livestock production, aquaculture , and forestry for food and non-food products. Agriculture
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#1732797717067984-404: A significant decrease in genetic diversity and resources among livestock breeds, leading to a corresponding decrease in disease resistance and local adaptations previously found among traditional breeds. Grassland based livestock production relies upon plant material such as shrubland , rangeland , and pastures for feeding ruminant animals. Outside nutrient inputs may be used, however manure
1066-492: A small area of forest is cleared by cutting and burning the trees. The cleared land is used for growing crops for a few years until the soil becomes too infertile, and the area is abandoned. Another patch of land is selected and the process is repeated. This type of farming is practiced mainly in areas with abundant rainfall where the forest regenerates quickly. This practice is used in Northeast India, Southeast Asia, and
1148-420: A traditional technique establishing fundamental occurrences or petrologic relationships. Clay minerals are common weathering products (including weathering of feldspar ) and low-temperature hydrothermal alteration products. Clay minerals are very common in soils, in fine-grained sedimentary rocks such as shale , mudstone , and siltstone and in fine-grained metamorphic slate and phyllite . Given
1230-540: A very common material, and is the oldest known ceramic . Prehistoric humans discovered the useful properties of clay and used it for making pottery . The chemistry of clay, including its capacity to retain nutrient cations such as potassium and ammonium , is important to soil fertility. Because the individual particles in clay are less than 4 micrometers (0.00016 in) in size, they cannot be characterized by ordinary optical or physical methods. The crystallographic structure of clay minerals became better understood in
1312-552: A year, or requiring irrigation. In all of these environments perennial crops are grown (coffee, chocolate) and systems are practiced such as agroforestry . In temperate environments, where ecosystems were predominantly grassland or prairie , highly productive annual farming is the dominant agricultural system. Important categories of food crops include cereals, legumes, forage, fruits and vegetables. Natural fibers include cotton, wool , hemp , silk and flax . Specific crops are cultivated in distinct growing regions throughout
1394-473: A yearly summit to discuss safety. Overall production varies by country as listed. The twenty largest countries by agricultural output (in nominal terms) at peak level as of 2018, according to the IMF and CIA World Factbook . Cropping systems vary among farms depending on the available resources and constraints; geography and climate of the farm; government policy; economic, social and political pressures; and
1476-584: Is a hybrid of a Chilean and a North American species, developed by breeding in Europe and North America. The indigenous people of the Southwest and the Pacific Northwest practiced forest gardening and fire-stick farming . The natives controlled fire on a regional scale to create a low-intensity fire ecology that sustained a low-density agriculture in loose rotation; a sort of "wild" permaculture . A system of companion planting called
1558-596: Is also extracted from the Doig Formation in conventional reservoirs along the western Montney trend and in the Peace River Arch . Argillaceous minerals Clay minerals are hydrous aluminium phyllosilicates (e.g. kaolin , Al 2 Si 2 O 5 ( OH ) 4 ), sometimes with variable amounts of iron , magnesium , alkali metals , alkaline earths , and other cations found on or near some planetary surfaces . Clay minerals form in
1640-626: Is both a cause of and sensitive to environmental degradation , such as biodiversity loss , desertification , soil degradation , and climate change , all of which can cause decreases in crop yield. Genetically modified organisms are widely used, although some countries ban them . The word agriculture is a late Middle English adaptation of Latin agricultūra , from ager 'field' and cultūra ' cultivation ' or 'growing'. While agriculture usually refers to human activities, certain species of ant , termite and beetle have been cultivating crops for up to 60 million years. Agriculture
1722-444: Is defined with varying scopes, in its broadest sense using natural resources to "produce commodities which maintain life, including food, fiber, forest products, horticultural crops, and their related services". Thus defined, it includes arable farming , horticulture, animal husbandry and forestry , but horticulture and forestry are in practice often excluded. It may also be broadly decomposed into plant agriculture , which concerns
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#17327977170671804-504: Is formed from a stack of layers interspaced with the interlayers. Clay minerals can be classified as 1:1 or 2:1. A 1:1 clay would consist of one tetrahedral sheet and one octahedral sheet, and examples would be kaolinite and serpentinite . A 2:1 clay consists of an octahedral sheet sandwiched between two tetrahedral sheets, and examples are talc , vermiculite , and montmorillonite . The layers in 1:1 clays are uncharged and are bonded by hydrogen bonds between layers, but 2:1 layers have
1886-400: Is known as corrensite , R1 illite-smectite is rectorite . X-ray rf(001) is the spacing between layers in nanometers, as determined by X-ray crystallography. Glycol (mg/g) is the adsorption capacity for glycol, which occupies the interlayer sites when the clay is exposed to a vapor of ethylene glycol at 60 °C (140 °F) for eight hours. CEC is the cation exchange capacity of
1968-431: Is only one tetrahedral and one octahedral group in each layer the clay is known as a 1:1 clay. The alternative, known as a 2:1 clay, has two tetrahedral sheets with the unshared vertex of each sheet pointing towards each other and forming each side of the octahedral sheet. Bonding between the tetrahedral and octahedral sheets requires that the tetrahedral sheet becomes corrugated or twisted, causing ditrigonal distortion to
2050-438: Is returned directly to the grassland as a major nutrient source. This system is particularly important in areas where crop production is not feasible because of climate or soil, representing 30–40 million pastoralists. Mixed production systems use grassland, fodder crops and grain feed crops as feed for ruminant and monogastric (one stomach; mainly chickens and pigs) livestock. Manure is typically recycled in mixed systems as
2132-500: The Indus Valley civilization . In China, from the 5th century BC, there was a nationwide granary system and widespread silk farming . Water-powered grain mills were in use by the 1st century BC, followed by irrigation. By the late 2nd century, heavy ploughs had been developed with iron ploughshares and mouldboards . These spread westwards across Eurasia. Asian rice was domesticated 8,200–13,500 years ago – depending on
2214-583: The Paleolithic , after 10,000 BC. Staple food crops were grains such as wheat and barley, alongside industrial crops such as flax and papyrus . In India , wheat, barley and jujube were domesticated by 9,000 BC, soon followed by sheep and goats. Cattle, sheep and goats were domesticated in Mehrgarh culture by 8,000–6,000 BC. Cotton was cultivated by the 5th–4th millennium BC. Archeological evidence indicates an animal-drawn plough from 2,500 BC in
2296-514: The Tigris and Euphrates rivers and a canal system for irrigation. Ploughs appear in pictographs around 3,000 BC; seed-ploughs around 2,300 BC. Farmers grew wheat, barley, vegetables such as lentils and onions, and fruits including dates, grapes, and figs. Ancient Egyptian agriculture relied on the Nile River and its seasonal flooding. Farming started in the predynastic period at the end of
2378-782: The Whitehorse Formation in the Muskwa Ranges , and with the Toad Formation in the upper Liard River area. The Doig formation is an important source rock for the Triassic Halfway and Charlie Lake formations. Total organic carbon values in the "phosphate zone" at the base of the Doig are commonly greater than 4% by weight and can reach up to 11%. The "phosphate zone" is also a potential undeveloped shale gas reservoir with as much as 400 trillion cubic feet of natural gas in place. Oil and gas
2460-630: The molecular clock estimate that is used – on the Pearl River in southern China with a single genetic origin from the wild rice Oryza rufipogon . In Greece and Rome , the major cereals were wheat, emmer, and barley, alongside vegetables including peas, beans, and olives. Sheep and goats were kept mainly for dairy products. In the Americas, crops domesticated in Mesoamerica (apart from teosinte) include squash, beans, and cacao . Cocoa
2542-548: The organic movement . Unsustainable farming practices in North America led to the Dust Bowl of the 1930s. Pastoralism involves managing domesticated animals. In nomadic pastoralism , herds of livestock are moved from place to place in search of pasture, fodder, and water. This type of farming is practiced in arid and semi-arid regions of Sahara , Central Asia and some parts of India. In shifting cultivation ,
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2624-407: The polymerization of RNA in aqueous solution from nucleotide monomers, and the formation of membranes from lipids. In 1998, Hyman Hartman proposed that "the first organisms were self-replicating iron-rich clays which fixed carbon dioxide into oxalic acid and other dicarboxylic acids . This system of replicating clays and their metabolic phenotype then evolved into the sulfide rich region of
2706-993: The 1930s with advancements in the x-ray diffraction (XRD) technique indispensable to deciphering their crystal lattice. Clay particles were found to be predominantly sheet silicate (phyllosilicate) minerals, now grouped together as clay minerals. Their structure is based on flat hexagonal sheets similar to those of the mica group of minerals. Standardization in terminology arose during this period as well, with special attention given to similar words that resulted in confusion, such as sheet and plane. Because clay minerals are usually (but not necessarily) ultrafine-grained, special analytical techniques are required for their identification and study. In addition to X-ray crystallography, these include electron diffraction methods, various spectroscopic methods such as Mössbauer spectroscopy , infrared spectroscopy , Raman spectroscopy , and SEM - EDS or automated mineralogy processes. These methods can be augmented by polarized light microscopy ,
2788-540: The Amazon Basin. Subsistence farming is practiced to satisfy family or local needs alone, with little left over for transport elsewhere. It is intensively practiced in Monsoon Asia and South-East Asia. An estimated 2.5 billion subsistence farmers worked in 2018, cultivating about 60% of the earth's arable land . Intensive farming is cultivation to maximize productivity, with a low fallow ratio and
2870-560: The Americas. Irrigation , crop rotation , and fertilizers advanced from the 17th century with the British Agricultural Revolution , allowing global population to rise significantly. Since 1900, agriculture in developed nations, and to a lesser extent in the developing world, has seen large rises in productivity as mechanization replaces human labor, and assisted by synthetic fertilizers , pesticides, and selective breeding . The Haber-Bosch method allowed
2952-586: The Paleolithic Levant, 23,000 years ago, cereals cultivation of emmer , barley , and oats has been observed near the sea of Galilee. Rice was domesticated in China between 11,500 and 6,200 BC with the earliest known cultivation from 5,700 BC, followed by mung , soy and azuki beans. Sheep were domesticated in Mesopotamia between 13,000 and 11,000 years ago. Cattle were domesticated from
3034-486: The Three Sisters was developed in North America. The three crops were winter squash , maize, and climbing beans. Indigenous Australians , long supposed to have been nomadic hunter-gatherers , practiced systematic burning, possibly to enhance natural productivity in fire-stick farming. Scholars have pointed out that hunter-gatherers need a productive environment to support gathering without cultivation. Because
3116-793: The United Nations (FAO) posits that the roles and responsibilities of women in agriculture may be changing – for example, from subsistence farming to wage employment, and from contributing household members to primary producers in the context of male-out-migration. In general, women account for a greater share of agricultural employment at lower levels of economic development, as inadequate education, limited access to basic infrastructure and markets, high unpaid work burden and poor rural employment opportunities outside agriculture severely limit women's opportunities for off-farm work. Women who work in agricultural production tend to do so under highly unfavorable conditions. They tend to be concentrated in
3198-524: The United States is roughly 1.7 times more productive than it was in 1948. Agriculture employed 873 million people in 2021, or 27% of the global workforce, compared with 1 027 million (or 40%) in 2000. The share of agriculture in global GDP was stable at around 4% since 2000–2023. Despite increases in agricultural production and productivity, between 702 and 828 million people were affected by hunger in 2021. Food insecurity and malnutrition can be
3280-544: The annual work-related death toll among agricultural employees is at least 170,000, twice the average rate of other jobs. In addition, incidences of death, injury and illness related to agricultural activities often go unreported. The organization has developed the Safety and Health in Agriculture Convention, 2001 , which covers the range of risks in the agriculture occupation, the prevention of these risks and
3362-440: The applications of clays include drug delivery, tissue engineering, and bioprinting. Clay minerals can be incorporated in lime-metakaolin mortars to improve mechanical properties. Electrochemical separation helps to obtain modified saponite-containing products with high smectite-group minerals concentrations, lower mineral particles size, more compact structure, and greater surface area. These characteristics open possibilities for
Doig Formation - Misplaced Pages Continue
3444-553: The available work force, were employed in agriculture. This constitutes approximately 70% of the global employment of children, and in many countries constitutes the largest percentage of women of any industry. The service sector overtook the agricultural sector as the largest global employer in 2007. In many developed countries, immigrants help fill labor shortages in high-value agriculture activities that are difficult to mechanize. Foreign farm workers from mostly Eastern Europe, North Africa and South Asia constituted around one-third of
3526-571: The average pH level of 7.1 is reached at 30% of the pulp added and an experimental site with perennial grasses proved the efficacy of the technique. Moreover, the reclamation of disturbed lands is an integral part of the social and environmental responsibility of the mining company and this scenario addresses the community necessities at both local and regional levels. The results of glycol adsorption, cation exchange capacity, X-ray diffraction, differential thermal analysis, and chemical tests all give data that may be used for quantitative estimations. After
3608-597: The central west coast and eastern central, early farmers cultivated yams, native millet, and bush onions, possibly in permanent settlements. In the Middle Ages , compared to the Roman period , agriculture in Western Europe became more focused on self-sufficiency . The agricultural population under feudalism was typically organized into manors consisting of several hundred or more acres of land presided over by
3690-482: The clay. K 2 O (%) is the percent content of potassium oxide in the clay. DTA describes the differential thermal analysis curve of the clay. The clay hypothesis for the origin of life was proposed by Graham Cairns-Smith in 1985. It postulates that complex organic molecules arose gradually on pre-existing, non-organic replication surfaces of silicate crystals in contact with an aqueous solution. The clay mineral montmorillonite has been shown to catalyze
3772-468: The cultivation of useful plants, and animal agriculture , the production of agricultural animals. The development of agriculture enabled the human population to grow many times larger than could be sustained by hunting and gathering . Agriculture began independently in different parts of the globe, and included a diverse range of taxa , in at least 11 separate centers of origin . Wild grains were collected and eaten from at least 105,000 years ago. In
3854-668: The domestication of squash (Cucurbita) and other plants. Coca was domesticated in the Andes, as were the peanut, tomato, tobacco, and pineapple . Cotton was domesticated in Peru by 3,600 BC. Animals including llamas , alpacas , and guinea pigs were domesticated there. In North America , the indigenous people of the East domesticated crops such as sunflower , tobacco, squash and Chenopodium . Wild foods including wild rice and maple sugar were harvested. The domesticated strawberry
3936-433: The dwarf planet Ceres , asteroid 101955 Bennu , and comet Tempel 1 , as well as Jupiter's moon Europa . Like all phyllosilicates, clay minerals are characterised by two-dimensional sheets of corner-sharing SiO 4 tetrahedra or AlO 4 octahedra. The sheet units have the chemical composition (Al, Si) 3 O 4 . Each silica tetrahedron shares three of its vertex oxygen ions with other tetrahedra, forming
4018-432: The farm itself, entire families can be at risk for injuries, illness, and death. Ages 0–6 may be an especially vulnerable population in agriculture; common causes of fatal injuries among young farm workers include drowning, machinery and motor accidents, including with all-terrain vehicles. The International Labor Organization considers agriculture "one of the most hazardous of all economic sectors". It estimates that
4100-430: The forests of New Guinea have few food plants, early humans may have used "selective burning" to increase the productivity of the wild karuka fruit trees to support the hunter-gatherer way of life. The Gunditjmara and other groups developed eel farming and fish trapping systems from some 5,000 years ago. There is evidence of 'intensification' across the whole continent over that period. In two regions of Australia,
4182-422: The greater use of pesticides and fertilizers. Multiple cropping , in which several crops are grown sequentially in one year, and intercropping , when several crops are grown at the same time, are other kinds of annual cropping systems known as polycultures . In subtropical and arid environments, the timing and extent of agriculture may be limited by rainfall, either not allowing multiple annual crops in
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#17327977170674264-454: The hexagonal array, and the octahedral sheet is flattened. This minimizes the overall bond-valence distortions of the crystallite. Depending on the composition of the tetrahedral and octahedral sheets, the layer will have no charge or will have a net negative charge. If the layers are charged this charge is balanced by interlayer cations such as Na or K or by a lone octahedral sheet. The interlayer may also contain water. The crystal structure
4346-425: The hot spring acquiring the ability to fix nitrogen . Finally phosphate was incorporated into the evolving system which allowed the synthesis of nucleotides and phospholipids." The structural and compositional versatility of clay minerals gives them interesting biological properties. Due to disc-shaped and charged surfaces, clay interacts with a range of drugs, protein, polymers, DNA, or other macromolecules. Some of
4428-441: The input of nutrients (fertilizer or manure ) and some manual pest control . Annual cultivation is the next phase of intensity in which there is no fallow period. This requires even greater nutrient and pest control inputs. Further industrialization led to the use of monocultures , when one cultivar is planted on a large acreage. Because of the low biodiversity , nutrient use is uniform and pests tend to build up, necessitating
4510-476: The lower yield associated with organic farming and its impact on global food security . Recent mainstream technological developments include genetically modified food . By 2015, the agricultural output of China was the largest in the world, followed by the European Union, India and the United States. Economists measure the total factor productivity of agriculture, according to which agriculture in
4592-452: The manufacture of high-quality ceramics and heavy-metal sorbents from saponite-containing products. Furthermore, tail grinding occurs during the preparation of the raw material for ceramics; this waste reprocessing is of high importance for the use of clay pulp as a neutralizing agent, as fine particles are required for the reaction. Experiments on the histosol deacidification with the alkaline clay slurry demonstrated that neutralization with
4674-437: The philosophy and culture of the farmer. Shifting cultivation (or slash and burn ) is a system in which forests are burnt, releasing nutrients to support cultivation of annual and then perennial crops for a period of several years. Then the plot is left fallow to regrow forest, and the farmer moves to a new plot, returning after many more years (10–20). This fallow period is shortened if population density grows, requiring
4756-414: The poorest countries, where alternative livelihoods are not available, and they maintain the intensity of their work in conditions of climate-induced weather shocks and in situations of conflict. Women are less likely to participate as entrepreneurs and independent farmers and are engaged in the production of less lucrative crops. The gender gap in land productivity between female- and male managed farms of
4838-400: The presence of water and have been important to life, and many theories of abiogenesis involve them. They are important constituents of soils , and have been useful to humans since ancient times in agriculture and manufacturing . Clay is a very fine-grained geologic material that develops plasticity when wet, but becomes hard, brittle and non–plastic upon drying or firing . It is
4920-440: The production of fish for human consumption in confined operations, is one of the fastest growing sectors of food production, growing at an average of 9% a year between 1975 and 2007. During the second half of the 20th century, producers using selective breeding focused on creating livestock breeds and crossbreeds that increased production, while mostly disregarding the need to preserve genetic diversity . This trend has led to
5002-455: The quantities of organic matter, carbonates, free oxides, and nonclay minerals have been determined, the percentages of clay minerals are estimated using the appropriate glycol adsorption, cation exchange capacity, K20, and DTA data. The amount of illite is estimated from the K20 content since this is the only clay mineral containing potassium. Argillaceous rocks are those in which clay minerals are
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#17327977170675084-597: The requirement of water, clay minerals are relatively rare in the Solar System , though they occur extensively on Earth where water has interacted with other minerals and organic matter . Clay minerals have been detected at several locations on Mars , including Echus Chasma , Mawrth Vallis , the Memnonia quadrangle and the Elysium quadrangle . Spectrography has confirmed their presence on celestial bodies including
5166-477: The result of conflict, climate extremes and variability and economic swings. It can also be caused by a country's structural characteristics such as income status and natural resource endowments as well as its political economy. Pesticide use in agriculture went up 62% between 2000 and 2021, with the Americas accounting for half the use in 2021. The International Fund for Agricultural Development posits that an increase in smallholder agriculture may be part of
5248-874: The role that individuals and organizations engaged in agriculture should play. In the United States, agriculture has been identified by the National Institute for Occupational Safety and Health as a priority industry sector in the National Occupational Research Agenda to identify and provide intervention strategies for occupational health and safety issues. In the European Union, the European Agency for Safety and Health at Work has issued guidelines on implementing health and safety directives in agriculture, livestock farming, horticulture, and forestry. The Agricultural Safety and Health Council of America (ASHCA) also holds
5330-478: The salaried agricultural workforce in Spain, Italy, Greece and Portugal in 2013. In the United States of America, more than half of all hired farmworkers (roughly 450,000 workers) were immigrants in 2019, although the number of new immigrants arriving in the country to work in agriculture has fallen by 75 percent in recent years and rising wages indicate this has led to a major labor shortage on U.S. farms. Around
5412-439: The same size is 24 percent. On average, women earn 18.4 percent less than men in wage employment in agriculture; this means that women receive 82 cents for every dollar earned by men. Progress has been slow in closing gaps in women's access to irrigation and in ownership of livestock, too. Women in agriculture still have significantly less access than men to inputs, including improved seeds, fertilizers and mechanized equipment. On
5494-488: The solution to concerns about food prices and overall food security , given the favorable experience of Vietnam. Agriculture provides about one-quarter of all global employment, more than half in sub-Saharan Africa and almost 60 percent in low-income countries. As countries develop, other jobs have historically pulled workers away from agriculture, and labor-saving innovations increase agricultural productivity by reducing labor requirements per unit of output. Over time,
5576-400: The synthesis of ammonium nitrate fertilizer on an industrial scale, greatly increasing crop yields and sustaining a further increase in global population. Modern agriculture has raised or encountered ecological, political, and economic issues including water pollution , biofuels , genetically modified organisms , tariffs and farm subsidies , leading to alternative approaches such as
5658-437: The term reichweite , which is German for range or reach. Literature articles will refer to an R1 ordered illite-smectite, for example. This type would be ordered in an illite-smectite-illite-smectite (ISIS) fashion. R0 on the other hand describes random ordering, and other advanced ordering types are also found (R3, etc.). Mixed layer clay minerals which are perfect R1 types often get their own names. R1 ordered chlorite-smectite
5740-402: The tetrahedral sheet also forms part of one side of the octahedral sheet, but an additional oxygen atom is located above the gap in the tetrahedral sheet at the center of the six tetrahedra. This oxygen atom is bonded to a hydrogen atom forming an OH group in the clay structure. Clays can be categorized depending on the way that tetrahedral and octahedral sheets are packaged into layers . If there
5822-679: The transition from hunter-gatherer to agricultural societies indicate an initial period of intensification and increasing sedentism ; examples are the Natufian culture in the Levant , and the Early Chinese Neolithic in China. Then, wild stands that had previously been harvested started to be planted, and gradually came to be domesticated. In Eurasia, the Sumerians started to live in villages from about 8,000 BC, relying on
5904-671: The wild aurochs in the areas of modern Turkey and Pakistan some 10,500 years ago. Pig production emerged in Eurasia, including Europe, East Asia and Southwest Asia, where wild boar were first domesticated about 10,500 years ago. In the Andes of South America, the potato was domesticated between 10,000 and 7,000 years ago, along with beans, coca , llamas , alpacas , and guinea pigs . Sugarcane and some root vegetables were domesticated in New Guinea around 9,000 years ago. Sorghum
5986-744: The world consist of fewer than 2 hectares (4.9 acres), and take up only around 12% of all agricultural land. Farms and farming greatly influence rural economics and greatly shape rural society , affecting both the direct agricultural workforce and broader businesses that support the farms and farming populations. The major agricultural products can be broadly grouped into foods , fibers , fuels , and raw materials (such as rubber ). Food classes include cereals ( grains ), vegetables , fruits , cooking oils , meat , milk , eggs , and fungi . Global agricultural production amounts to approximately 11 billion tonnes of food, 32 million tonnes of natural fibers and 4 billion m of wood. However, around 14% of
6068-781: The world's agricultural land is seriously degraded. In recent years there has been a backlash against the environmental effects of conventional agriculture, resulting in the organic , regenerative , and sustainable agriculture movements. One of the major forces behind this movement has been the European Union , which first certified organic food in 1991 and began reform of its Common Agricultural Policy (CAP) in 2005 to phase out commodity-linked farm subsidies, also known as decoupling . The growth of organic farming has renewed research in alternative technologies such as integrated pest management , selective breeding, and controlled-environment agriculture . There are concerns about
6150-664: The world's food is lost from production before reaching the retail level. Modern agronomy , plant breeding , agrochemicals such as pesticides and fertilizers , and technological developments have sharply increased crop yields , but also contributed to ecological and environmental damage . Selective breeding and modern practices in animal husbandry have similarly increased the output of meat, but have raised concerns about animal welfare and environmental damage. Environmental issues include contributions to climate change , depletion of aquifers , deforestation , antibiotic resistance , and other agricultural pollution . Agriculture
6232-485: The world, women make up a large share of the population employed in agriculture. This share is growing in all developing regions except East and Southeast Asia where women already make up about 50 percent of the agricultural workforce. Women make up 47 percent of the agricultural workforce in sub-Saharan Africa, a rate that has not changed significantly in the past few decades. However, the Food and Agriculture Organization of
6314-495: The world. In the 20th century, industrial agriculture based on large-scale monocultures came to dominate agricultural output. As of 2021 , small farms produce about one-third of the world's food, but large farms are prevalent. The largest 1% of farms in the world are greater than 50 hectares (120 acres) and operate more than 70% of the world's farmland. Nearly 40% of agricultural land is found on farms larger than 1,000 hectares (2,500 acres). However, five of every six farms in
6396-621: The world. Production is listed in millions of metric tons, based on FAO estimates. Animal husbandry is the breeding and raising of animals for meat, milk, eggs , or wool , and for work and transport. Working animals , including horses, mules , oxen , water buffalo , camels, llamas, alpacas, donkeys, and dogs, have for centuries been used to help cultivate fields, harvest crops, wrangle other animals, and transport farm products to buyers. Livestock production systems can be defined based on feed source, as grassland-based, mixed, and landless. As of 2010 , 30% of Earth's ice- and water-free area
6478-444: Was a key factor in the rise of sedentary human civilization , whereby farming of domesticated species created food surpluses that enabled people to live in the cities. While humans started gathering grains at least 105,000 years ago, nascent farmers only began planting them around 11,500 years ago. Sheep, goats, pigs, and cattle were domesticated around 10,000 years ago. Plants were independently cultivated in at least 11 regions of
6560-640: Was domesticated by the Mayo Chinchipe of the upper Amazon around 3,000 BC. The turkey was probably domesticated in Mexico or the American Southwest. The Aztecs developed irrigation systems, formed terraced hillsides, fertilized their soil, and developed chinampas or artificial islands. The Mayas used extensive canal and raised field systems to farm swampland from 400 BC. In South America agriculture may have begun about 9000 BC with
6642-560: Was domesticated in the Sahel region of Africa by 7,000 years ago. Cotton was domesticated in Peru by 5,600 years ago, and was independently domesticated in Eurasia. In Mesoamerica , wild teosinte was bred into maize (corn) from 10,000 to 6,000 years ago. The horse was domesticated in the Eurasian Steppes around 3500 BC. Scholars have offered multiple hypotheses to explain the historical origins of agriculture. Studies of
6724-584: Was used for producing livestock, with the sector employing approximately 1.3 billion people. Between the 1960s and the 2000s, there was a significant increase in livestock production, both by numbers and by carcass weight, especially among beef, pigs and chickens, the latter of which had production increased by almost a factor of 10. Non-meat animals, such as milk cows and egg-producing chickens, also showed significant production increases. Global cattle, sheep and goat populations are expected to continue to increase sharply through 2050. Aquaculture or fish farming,
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