agriculture: a human induced global megatrend
TRANSCRIPT
Agriculture: a human induced global megatrend
Land Cover Change and Agriculture
• The most significant historical change in land cover has been the expansion of agricultural lands at the expense of grasslands and forests.
• Today close to 1/3 of the Earth's land surface is devoted to pastures or cropland
• Which amounts to approximately 1/2 of all lands suitable for agriculture.
Land Cover Change and Agriculture
• Since the dawn of plant domestication the progression of cropland was relatively slow.
• The past century witnessed over half of the worldwide increase in agricultural lands, and in the developing world half the land cover conversion occurred in just the past 50 years (Houghton 1994).
SAGE
Agriculture• Most people today eat food they produce themselves or that is
produced for them – only a few hunter / gatherers remain• Hunter gathering lifestyle dominated for c. 7 million of
years. Around 11,000 years ago people turned to food production, domesticating animals and plants – WHY?
Agriculture• Food production was acquired at different times by
different peoples – some never acquired it at all (e.g. Australian aborigines)
• Some developed it independently – e.g. China• Most species are inedible, no nutritional value, difficult to
hunt or gather• By selecting and growing the edible plants – 1 acre can
feed 10-100 times more people than hunting/gathering • Domesticated animals – provide meat, milk, and pulling of
plows– Manure for fertilizing but also for fuel
• Plow animals enabled working of heavier soils – rather than using digging sticks
Optional Reading on the evolution of Agriculture - Guns Germs and Steel: Jared Diamond
Then and Now
Here and There
Archaeology• Plant and animal remains
– Domesticated cattle and sheep are smaller, chickens and apples are larger – WHY?
– Carbon dating (slow decay of C14, C14 ratio to C12 – once dead - decay of half C14 every 5,700 yrs)
• First crops were wheat, barley and peas – These grew quickly and could be harvested within a
few months of sowing – self pollinating • First fruit and nut trees – 4000 BC
– Olives, figs, dates, pomegranates and grapes – 3 year investment needed
– Apples, pears, plums came later - grafting developed in China
5 main centers of independent food production
Region Crops Animals Time (BC)• SW Asia: wheat, pea, olive sheep, goat 8500• China: rice, millet pig, silkworm 7500• Mesoamerica: corn, beans, squash 3500• Andes (Amazonia): potato, manioc llama 3500 • E. USA: sunflower none 2500
• Uncertainties regarding W. Africa (sorghum - 5000 BC), Ethiopia (coffee), New Guinea (sugar cane – 7000 BC)
• Europe – arrival of SW crops and animals between 6000 and 3500 BC - Indus valley 7000BC, Egypt
• By Roman times almost all today’s leading crops were being grown somewhere.
Fertile Crescent
Why the Fertile Crescent?• Mediterranean climate – mild wet winters, long dry summers
– big seeded annual plants (6 of the modern worlds 12 major crops)
• Large number of species of large seeded grass species - wild cereals from this region can produce a ton of seed per hectare – 50 cals of food for 1 calorie expended
• Some hunter gatherers had settled in permanent villages prior to cultivating plants
• Fertile crescent flora includes a high percentage of self pollinating plants
• Range of altitude meant a staggering of the harvest season• Biological diversity offered animals suitable for
domestication – goat, sheep, pig, cow – wild ancestors common in different parts of the region.
Why the Fertile Crescent?Early domestication of 8 crops (founder crops)
–Emmer wheat, einkorn wheat, barley, pulses, pea, chickpea, bitter vetch and flax
• Not the people but the environment – Environmental Determinism?
• Earliest site for agriculture, cities, writing, empires - all sprang from dense human population, stored food surpluses, feeding of non-farming specialists.
Early Cereals Emmer Wheat
Einkorn Wheat
Barley
FLAX
Transition to Agriculture• 8,500 B.C. in the Fertile Crescent a move from hunter-
gathering to food production • Archaeologists have demonstrated that first farmers in
many areas were less nourished and died younger than the hunter gatherers they replaced.
• Food production was not invented or discovered – it evolved
• Not a sharp divide between hunter gatherers and sedentary food producers - even today – Sedentary groups were hunter gatherers– Food producers can be mobile – forest gardens– Mix of seasonal food production and hunter gathering
• Misconception that food producers were active managers of the land and hunter gatherers weren’t– Hunter gatherers also manage the land (e.g. fire, clearing)
• The shift from hunter gathering to sole dependence on food production took thousands of years ~ 6000 years – Simultaneous collection of wild foods and cultivated ones
What caused the shift from hunter gathering to agriculture?– Decline in availability of wild foods – Extinction of large mammals
• Rise in skill – number of hunters • ...depletion of wild game
– Climate change at the end of the Pleistocene• increased extent of wild cereals in the fertile crescent
– Cumulative development of food production technologies (collecting, processing, storing)• Emergence of flint sickles, baskets, mortars and pestles, grinding
slabs, roasting grains, storage pits– Increasing population
• Sedentary life – shortened birth spacing• Increasing population – higher than food supply – nutrition
– Denser population of food producers displaced hunter gatherers or hunter gatherers adopted food production
Transition to Agriculture
• Only where geographic or ecological barriers prevented immigration of food producers or diffusion of locally appropriate food producing techniques – were hunter gatherers able to persist until modern times e.g. – Native Americans in California – separated from
Arizona by desert– Khoisan hunter gatherers at the Cape, S. Africa –
Mediterranean climate– Australian aborigines from New Guinea - Torres
Straight
Development of Agriculture 2500 BC to 500 AD Little change in agriculture
• Subsistence farming - still exists today in large parts of the world
Some new technologies • Irrigated flood plains – China, Egypt, Near East
Fertilizer • manure and fodder
Prior to 18th Century • Agriculture was much the same across Europe and had
been since before the Middle Ages (5th to 16th Century). The system in operation was essentially post-feudal, with each villager subsistence farming their own strips of land
European Agricultural Revolution Crop Rotation
• During the Middle Ages, the open field system had employed a three year crop rotation, with a different crop in each of the three fields – e.g. wheat and barley in two, with the third fallow.
• Following the Black Death, 30-60% depopulation made possible a shift in diet away from cereals towards meat and other animal products.
• Correspondingly, legumes such as peas and beans, (excellent livestock fodder), replaced barley as the spring crop in the three-field crop rotation. Also, some crop fields were retired towards permanent pasture and increased the fertility of croplands.
European Agricultural Revolution 18th Century: Crop Rotation
• The Dutch discovered a still more effective four-field rotation system, introducing turnips and clover to replace the fallow year.
• Clover was both an ideal fodder crop, and it improved grain yields in the following year, simultaneously increasing cereal and livestock production.
• The-four field system was promoted in England by Viscount Charles “Turnip” Townshend and increased productivity by 50%
Technological Advances
• 1600’s metal added to wooden plows• 1700 Jethro Tull’s seed drill • 1794 Eli Whitney’s cotton gin• Late 1700’s use of limestone• 1797 cast-iron moldboard plow• 1830’s John Deere’s steel plow• 1831 Cyrus McCormick’s reaper• 1838 First combine harvester (horse drawn)• Late 1800’s steam power replaces horse power• 1892 Froelich tractor (Ford 1907)
Agro Industrial period • Advances in agronomic science started in
the 19th century – genetics, chemical fertilizers, crops diseases
• Industrial revolution and food production• Revolution in transportation (railroad, the
steamer and refrigeration - 1870’s) • Mass consumption• 1910 BARC
– Scientific advances
The Green Revolution 1945 – 1980’s • The need
– More urban people, rapid population increase, food production not keeping pace
• The term coined by US AID Director (March 1968)– Movement to increase crop yields
• New cultivars• Fertilizer• Pesticides• Mechanization
• The promise– Eliminate hunger, increase global carrying capacity,
increase yields, increase technological knowledge, get the necessary materials to rural farmers
– Example – Mexico: • 1959 300 tonnes of Wheat > 1970 2.6m tonnes
The Green Revolution• Fertilizer
– Grain yields increased dramatically • Mexico 1950 - 1970
– 300,000 - 2,600, 000 metric tons of wheat• Worldwide 1950-1990
– 14 million to 144 million tons of food
• Irrigation– Tube wells and electric pumps– Minimize drought failures– Modern wells 5 times more water and more
efficient
Some fertilizer is good
More must be great…right?Tennessee Valley Authority: "Results of Fertilizer”, 1942
Case Study – China & Fertilizer• Since the 1980s agriculture yields have grown in
China, as has the nation's use of chemical fertilizers. In 2007, China consumed 32.6 million tonnes of nitrogen fertilizer, a 191% increase over 1981
• Results show that extensive overuse has caused the pH of soil across China to drop by roughly 0.5, with some soils reaching a pH of 5.07 - By contrast, soil left to its own devices would take at least 100 years to acidify by this amount
• The acidification has already lessened crop production by 30-50% in some areas
• “ In the final analysis, if the history of the Green Revolution has taught us one thing, it is that increased food production can-and often does-go hand in hand with greater hunger. If the very basis of staying competitive in farming is buying expensive inputs, then wealthier farmers will inexorably win out over the poor, who are unlikely to find adequate employment to compensate for the loss of farming livelihoods. Hunger is not caused by a shortage of food, and cannot be eliminated by producing more.
• This is why we must be skeptical when Monsanto, DuPont, Novartis, and other chemical-cum-biotechnology companies tell us that genetic engineering will boost crop yields and feed the hungry. The technologies they push have dubious benefits and well-documented risks, and the second Green Revolution they promise is no more likely to end hunger than the first.
• Far too many people do not have access to the food that is already available because of deep and growing inequality. If agriculture can play any role in alleviating hunger, it will only be to the extent that the bias toward wealthier and larger farmers is reversed through pro-poor alternatives like land reform and sustainable agriculture, which reduce inequality and make small farmers the center of an economically vibrant rural economy.” – Dr. Peter Rosset, Joseph Collins and Frances Moore Lapp, "Lessons from the Green Revolution ". Tikkun Magazine, Volume 15, No.2 March/April 2000
One Perspective
Another Perspective• The “green revolution” of the late 1960s averted widespread famine,
largely by introducing high-yielding, “modern semi-dwarf” varieties of rice and wheat. Future global agricultural strategies should adopt a “bottom-up” model as opposed to the “top-down” model on the basis that this approach will address the farmers’ needs. Prof Swaminathan advocates an “evergreen revolution”, through the application of appropriate technology, to provide a sustainable global agriculture that conserves natural resources, and a perennial green revolution in which everyone can share right down to the poorest farmer in the poorest part of the world.
• While eco-terrorists destroy valuable GM test sites, brandishing “save the world” banners, they fail to see that this is what scientists are seeking to do. Incorporating contemporary technologies into traditional practices, within a global framework, represents a new renaissance for agriculture, enabling more food to be produced from less land using fewer chemicals and natural resources. But unless more acceptable levels of resource consumption and reductions in emissions are also achieved, the high-consumption lifestyles currently enjoyed by the few could irretrievably threaten the environment and global prosperity - Dr Claire Cockcroft – Conf. paper - Global Agriculture 2020: Which way Forward
Recent Trends • Global
– Persistent increase and volatility in commodity prices – Fuel Prices
• Freight rates, Fertilizer costs, High feed prices– Increasing globalization of markets
• Exchange Rates – the falling $• Regional responses
– Europe releasing set aside land for production– India providing incentives for wheat – US wheat to Maize. - ethanol subsidies
• Regional US / Europe?– Green consumers: Organic, Locally produced – Agro-industrial complex– Carbon markets and agriculture – no tillage
Why Agricultural Monitoring? Agriculture is a fundamental component of societal well-being
• Challenges:– Changing global markets– Food Security for increasing
populations– Increasing productivity while
sustaining natural resources– Climate change and increased
frequency and severity of extreme weather events
– Growing competition for crops due to increasing demands for bio-fuels
31% 74% 87% 130%
Price Rises in a single Year, March 2007-March 2008
Corn
Rice SoyWheat
Source: Bloomberg. except Rice: FAO/Jackson Sons & Co
WORLD POPULATION GROWTH
1950 1975 2000 2025 2050
Source: UN
Source: FAS (Jim Crutchfield)
Source: USDA Agricultural Projections to 2016 Report
Projections of U.S Corn Use for Ethanol Production
What’s the general trend?
• Growth in wheat imports is concentrated in the developing countries, primarily North Africa, the Middle East, China, and Indonesia, where income growth underpins increases in demand
• Projected growth for wheat and coarse grains trade during 2000-10 is stronger than in the previous two decades, driven by rising incomes in developing regions, diet diversification, and increased demand for livestock products and feeds.
• Higher income countries of East Asia, such as Japan and South Korea, increase meat imports as their domestic livestock sectors are constrained by land availability and environmental issues.
• Meat consumption growth in China is met largely by expanding domestic production, but imports, particularly of poultry, are also projected to grow.
• Russia remains a large market for poultry imports as rising consumer demand outpaces increases in domestic production.
• Strong economic growth in Mexico along with trade liberalization under NAFTA will generate increases in beef, pork and poultry imports.
Feed the World?• 800 Million people are presently malnourished • By 2020 there will be 2-3 billion more people to feed
– 90% of them in poor countries– 50% of the population will be in urban areas not engaged
in food production• Current Concerns
– Climate change – winners and losers– Competing demand for Agricultural Land – Nutrition – Crop diversity (6 crops meet 90% of worlds food needs)
and– Food distribution – Ineffective agreements – Common Agricultural Policy and
WTO – Public perceptions about biotechnology science
Feed The World? • Possible Solutions
– Intensification • Technological advances (Biotechnology - GM, tissue
cultures, micropropogation, transgenic plants) • Economic instruments (microfinancing, profit
incentives, micro insurance, access to markets)– Extensification
• Convert new lands for agriculture. The greatest increases in land used for cultivation are predicted for Africa and Latin America, with substantial additional parts of Europe/Russia and North America also coming under cultivation to meet future demands for food.
Reading
oBeddington et al. – What next for Agriculture After Durban
oPeter Rosset – Lessons from the Green Revolution
o Claire Cockcroft – Setting the agenda for global agriculture
oOptional:• R.B. Singh – Environmental consequences of ag
development: a case study from the Green Revolution state of Haryana, India