Today, drylands cover more than 46% of the global land area where three billion people live. Nearly 30% of humans today have no indoor drinking water. The risk of desertification is growing. Farmland is under threat. Adaptation to climate change is the priority with climate change mitigation taking a back step.
In areas that have always been challenged by aridity and heat, collective wisdom and shared experiences are leading to advancements in technology and technique to ensure farms continue to produce enough to meet demand. Not all efforts to live in our hotter and more water-stressed world are producing equal results.
For example, take Australia. Second to Antarctica, it is the driest continent on the planet. But unlike Antarctica, people live there.
Almost all Australian agriculture today is dryland without irrigation. The vast majority is designated for grazing. Farm sizes have been doubling for several decades. Where staple crops are grown, most are designated for export.
Australian farms, today, are highly mechanized. In the 1980s, the Landcare movement started to tackle the known problems of degraded soils, and the loss of native vegetation well adapted to the continent’s dry climate. Despite the wide adoption of Landcare methods, the soils of Australia continue to degrade, and since 2020, staple crop dryland farm yields have plateaued.
Meanwhile, Australia is getting warmer with the country having recently added a new isotherm and colours to its weather maps as more places see daytime temperatures above 50+ Celsius (122 Fahrenheit). As the warming increases the interior of the country is getting drier. The few rivers it has often run dry. The soils are bone dry. When it rains (precipitation levels have been dropping throughout the last half century), the soil cannot absorb the water leading to flash floods that wash away more topsoil.
Implemented conservation approaches include zero tillage where crops are planted. Vast amounts of farmland lie fallow to try and restore soil moisture. Finally, Australian farmers are altering their growing seasons to try and match changes in precipitation patterns as they look for ideal periods of low evaporation for planting and dry spells for harvesting.
The Australian farm story is not a success, but rather, a growing challenge.
Other places on the planet are getting it right. One is eastern Oregon where dry farming strategies developed at Oregon State University have been adopted. Eastern Oregon is uber-dry and more often associated with cattle grazing. Using novel techniques, however, that encourage deep-root development has farmers growing melons, tomatoes and squash without adding a drop of irrigation water.
The methodology uses compressed soil when seeding or putting in transplants. The topsoil is fluffed to act like a mulch which helps to ensure soil water retention. The plants quickly develop large and deep root systems to tap into underground moisture.
Israel’s Negev is its desert south. It is dry and hot and covers 55% of the country. Yet more than 40% of Israel’s crops are grown in the Negev. Today, the country is the largest producer of dairy milk in terms of per-cow yield. It grows 300 tons of tomatoes per hectare compared to the global average of 50. It produces 262 tons of citrus per hectare compared to 243 and 211 tons in the United States and Europe respectively.
Water management has made the above numbers possible. Desalination of seawater serves the majority of domestic and industrial water needs. Israel recycles 90% of its wastewater compared to the U.S. at 10%.
Drip irrigation technology directly feeds individual plants rather than surrounding soil. Greenhouses extend the growing season year-round without adding to water demand.
Israel’s techniques and technology are shared with neighbouring countries in the Middle East and North Africa or MENA where the Agricultural or Neolithic Revolution was born.
MENA is the home for four of Earth’s five most water-stressed countries. It is also the place from which domesticated animals and plants sprung. This is an area that was named the Fertile Crescent by those studying ancient history. It spans from the Tigris-Euphrates to the Mediterranean and beyond to the Nile River.
The Middle East is the home of the first farms, the first towns, the first cities and the first kingdoms. It is where writing originated, where copper, bronze and iron were smelted and turned into hoes and ploughs. It is referred to as the Cradle of Western Civilization.
Now it is becoming the new cradle of wisdom to sustain humanity in a warming and drier world of the future. No place better serves our needs than the countries of MENA when it comes to agricultural innovation in the face of climate change. Here, temperatures are on the rise. Its deserts are spreading. It suffers from freshwater scarcity.
Yet, human ingenuity is allowing the people of MENA to tackle these challenges by studying the resilient plant and animal species undergoing rapid evolutionary change in their part of the world as they adapt to climate change.
Where domesticated plants breed true, their wild-related species that have been around for ten thousand years are still adapting to environmental changes. These are plants and animals that survive in the increased heat, grow even in deteriorating soil conditions as desertification spreads, and find where the water is when needed.
These are plants with genetic traits we can copy through genetic engineering and selective breeding to insert into the DNA of wheat, barley, and other grains.
In Morocco, the International Center for Agricultural Research in Dry Areas (ICARDA) has created a crop gene bank that has led to the release of 880 new crop varieties in the last 40 years. These include 120 climate-resilient cereal and legume crops that today are being grown in more than 20 countries.
MENA countries have created a drought index to monitor the extent and severity of water-stressed areas. They are working with the United States and other countries on the Agriculture Innovation Mission (AIM) for Climate (AIM4C), a project initially focused on food production in the Arabian Peninsula. The goal is to produce successes to be shared across the rest of MENA countries and other global dryland nations. These new dryland innovations are being introduced and scaled to provide:
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But the view from the Moon showed an Earth that was resplendent with water, a blue marble suspended in the inky blackness of the surrounding space. More than 70% ocean, it is hard to describe Earth as water starved. And yet one of the great challenges we face in the 21st century is the increasing scarcity of fresh, drinkable water. Why? Because we are exploiting more of it to address the needs of the 7.4 billion humans along with our livestock’s needs and industry demands. Compounding the water issue is a changing global climate, a product of rising greenhouse gases, and leading to changed weather patterns, and even ocean currents. One of those changes is happening in Western North America from the Baja Peninsula of Mexico, through California, Arizona, Nevada, the Great Basin, the Pacific Northwest, Canada’s west coast and prairie provinces and even Alaska. As evidence this June was the hottest and driest on record from California to Alaska with temperatures in the latter as hot as those recorded in the summer in Las Vegas.
In today’s Globe and Mail newspaper, an article describes the prolonged drought impacting farmers in Alberta where wheat, barley, canola and alfalfa crops are withering in the fields. The drought is akin to the one that California has experienced with rainfall levels less than 20% of norm. Those wonderful blue prairie skies almost cloud free with temperatures climbing into the mid-30s Celsius (30 equal 86 Fahrenheit) daily are not being enjoyed by farmers. Because what they mean is no rain in the forecast, and any that does fall cannot replenish the moisture being lost in between showers.
What’s the cause of Alberta farmers’ angst? The continued presence of warmer than normal ocean surface temperatures in the Central and North Pacific Ocean, thousands of kilometers away. Climate scientists tell us why the ocean is warmer. They remind us that 70% of global warming is being sequestered in the ocean. Warm water means warm air above and changes in barometric pressure and wind patterns. Hence much drier and warmer air entering the North American continent from the west and traveling as far north as Alaska and much of Western Canada.
In The Globe and Mail article which describes the drought Alberta farmers are facing, author Justin Giovannetti reports that “farmers across almost two-thirds of Alberta are coping with some of the driest conditions in decades….it could take years for the parched soil to recover.”
So what to do? How can farmers change their circumstances? Here are some ways to fight the heat and drought:
The governments of Alberta and other drought-prone jurisdictions have no solutions for farmers to fall back on. (In fact, when you read the Canadian federal government’s impact of climate change statement you first are treated to the opportunities regions of the country will get from increased carbon dioxide in the atmosphere – how bizarre!) Insurance for crop damage and loss and emergency funding programs can only go so far. And with ever smaller winter snow packs (also affected by the warming Pacific Ocean) the spring melt from the Rocky Mountains to the west means an ever diminishing flow of water to Alberta’s fields. Groundwater sources are drying up. Rivers are at their lowest levels, and Alberta farmers look to the skies for relief but find none.
In California water restrictions are trying to conserve what little remains in the aquifers of California’s Central Valley. New technology is helping farmers calculate how much what each plant they grow uses in water daily. Mulch from yard and construction debris is being applied to fields to reduce evaporation. Drip irrigation (the technology created by Israel’s Netafim) is cutting water use on some farms by as much as 25%.
In the second last action that farmers might take I mention genetically altered crops that can handle drought. What if farmers could find a plant that is drought resistant, discover the genetic characteristics that give it that advantage, and then introduce those genes into staple crops? That is in fact what some current researchers are attempting to do.
They are using the Agave, the plant that is used to make Tequila. Agave can withstand drought because its photosynthesis processes are different from that of wheat, barley and so many other crops. Agave uses a process called crassulacean acid metabolism (CAM) which lets its thrive on less water.
Work at Oak Ridge National Laboratory is trying to unlock the mystery of CAM, finding out which of almost 100 genes in the Agave plant allows it to thrive in semi and desert conditions. CAM works differently than most photosynthesis processes in most plants. Instead of absorbing CO2 during the day it turns the Agave into a “night breather.” Of course plants do not breathe, they absorb through open pores called stomata. With Agave’s pores open only at night rather than in the heat of the day, the plant loses less water through evapo-transpiration. This allows it to thrive on as little as 20% of the water needed by non-CAM plants (which are defined by botanist as C3 and C4). And because Agave takes in CO2 through the night it has to temporarily store it until the sun rises when it can break down the gas to perform photosynthesis.
The researchers have identified all the genes involved. They haven’t as of yet worked out the mechanism and order in which the genes instruct the Agave plant to perform its unusual “night breathing” adaptation to become the “camel of plants.” But once they do the intention is to create hybrid staple crop plants with CAM capability. The target plant is the poplar, a fast growing tree which has already been fully sequenced so we know its complete DNA. Once the research yields a hybrid-poplar the scientists will move on to try genetically altering corn and sorghum to decrease the amount of water needed for these crops to thrive.
It won’t come in time to help current Alberta farmers cope with drought. But for the more than 9 billion of us that will be alive in 2050, in a very much altered world, it could prove a life saver.
Related articles across the web
]]>In the 20th century our world population grew from 1.6 billion in 1900 to over 6 billion by 2000. In that same period our freshwater usage increased by a factor of 6. It is estimated by 2025 that 1/3 of our human population will reside in freshwater scarce countries. As we approach 9 billion or more by 2050 freshwater will become even more scarce.
As freshwater demands increase the volume of water which is finite will lead to a decline in the amount per human inhabitant. Based on a recent UNESCO report, the availability of freshwater will decline from an average of 7,300 cubic meters in 1995 to 4,800 in 2025 per person.
Conservation techniques can help us manage freshwater resources better. Applying technology to create water from air, or to desalinate it from the ocean can increase availability at an increased cost. An equivalent to a cap-and-trade system on freshwater usage can stimulate improved handling of freshwater resources, change agricultural practices and land usage patterns, and stimulate innovation. Through necessity, the 21st century will have to address freshwater with the same energy it puts into implementing energy conservation, renewable energy, and mitigation of climate change.
Freshwater Usage in Agriculture Today
The World Bank keeps data records on agricultural usage of freshwater by country. The statistics are revealing. Many of the poorest countries in the world are using water for agriculture at unsustainable rates. The following partial list groups countries by categories of my choosing:
Areas with ongoing wars, and civil unrest:
Afghanistan 99%
Egypt 86%
Eritrea 95%
Iran 92%
Iraq 79%
Israel 58%
Libya 83%
Pakistan 94%
Somalia 99%
Sudan 97%
Syria 88%
Areas stressed by over population
Bangladesh 88%
China 65%
India 90%
Indonesia 82%
Although the lack of freshwater may not be the primary creator of stress for the countries mentioned above there appears to be a correlation between war and over population, and the scarcity of freshwater.
On the other hand there are countries that have industrialized farming and are net food exporters. Their agricultural freshwater usage patterns are different. Here is a representative sample:
Argentina 66%.
Australia 74%
Canada 12%
United States 40%
Having lived in Canada all my life, a country that has never faced a freshwater shortage it is difficult to appreciate the challenge that so many countries face when because of freshwater scarcity. Increasingly even net food exporters like Australia and Argentina are experiencing drier conditions and are drawing on freshwater resources in much higher amounts than in the past. So scarcity is a growing problem everywhere.
Climate Change and Freshwater
In our last blog we talked about the impact of climate change on agriculture. Where climate change will have its greatest impact is in the distribution of freshwater. This will affect aquifers, snow packs, mountain glaciers, lake levels, river flow and volume, and the quantity and intensity of storms.
Atmospheric warming will shift growing zones. Sub-tropical vegetation will migrate further north. Arid regions will get drier leading to increased desertification. Wet areas are expected to get far wetter. Seasonal variation in precipitation will become more extreme. As glaciers and snow packs shrink the rivers that rely on them as water sources will experience greater fluctuations in volume. As sea levels rise coastal aquifers will be invaded by seawater and coastal land under tillage will be lost either through increased salinization or inundation.
Human Land Use, Migration and Freshwater
For more than 50 years in the United States human migration has steadily increased the population of southwestern states while depleting Great Lakes and northeastern states. The population shift is away from where freshwater exists in abundance to where it is scarce.
Increasingly humanity resides in cities. Most of our urban population lives along coasts whether by lakes and rivers or by seas and oceans.
Increasingly humanity puts forest land under cultivation removing trees and affecting groundwater tables and soil stability.
Canada which has more freshwater resources than any other country on the planet is thinly populated and even it is experiencing freshwater challenges in the Prairies as urban centres and agriculture compete for finite surface and subsurface water resources. Add to that the use of water in mining, oil sands extraction, and industry and you have a growing freshwater challenge.
Global Distribution of Freshwater Sources
Earth has water in abundance yet we face a freshwater crisis. That’s because most of the water we have isn’t fresh. And the freshwater that we do have is not distributed evenly or in locations where our largest human populations live.
The surface of the planet features oceans of saltwater, in fact 97.14% of the water on the planet. The preponderance of the remaining water, around 2% is locked up in polar and mountain ice and snow packs. Lakes, streams and rivers represent just 0.014% of the total. The rest is groundwater at 0.592%.
When you view Earth’s northern hemisphere from space you see the dominant features on the planet’s surface, water and ice.
Other than the large lakes and river systems visible on the lower left in North America most of the freshwater in this picture is in sea ice or glaciers. At the South Pole Antarctica is locked in ice surrounded by an endless ocean.
Where the Farms Are Today is not Necessarily Where Freshwater is Abundant
The Case of the United States
The American Mississippi-Missouri-Ohio River basin, California and Florida represent prime agricultural areas in the United States. These areas are increasingly feeling the demand for freshwater from urban centres, and for industrial use in addition to agriculture.
Freshwater usage as a percentage of precipitation amounts to about 30% in much of the American Great Plains. In some areas experiencing prolonged droughts such as Texas and parts of Oklahoma, Arkansas and Louisiana, that usage exceeds 100%.
California produces 400 different agricultural products including almost 50% of the fresh fruit, vegetables and nuts consumed in the United States. Much of what California farms produce goes to export representing 15% of the United States total exports. California farms rely for freshwater on the river and groundwater of the San Joaquin-Sacramento River system fed by glacier and snow pack melt from the Sierra Nevada Mountains.
Much of the land under tillage in California would not be producing crops if it weren’t for major irrigation projects started in the 1930s moving water from Northern California to farms in the southern part of the Central Valley. Increasing urban growth and industrial freshwater demands have led to additional water projects to move freshwater from locations outside the state. As a result Southern California receives 60% of its freshwater from the Colorado River.
For such an important agricultural centre of production the growing challenges of declining freshwater sources is leading to major efforts to conserve water through a variety of changes in agricultural practices. This is leading to new irrigation techniques to deliver water more directly to targeted crops, recycling and treatment of grey water for use in irrigation, and fallowing of land.
For Florida the threat to citrus crops comes not just from cyclical drought but also from increased salinity in the aquifer from which much of the freshwater is derived. Urban demands in Southern Florida compete directly with agricultural requirements. In recent years Lake Okeechobee has experienced declining water levels. Because so much of Florida is at or near sea level, any decline in water levels in the lake means gravity cannot assist in moving the water and imposes an extra cost in getting it to cities and farms.
Florida agriculture suffers further from its near sea level elevation. In some coastal areas, because of excessive drawing of groundwater, salt water from the ocean is making its way into the aquifer leading to high salinity levels.
The Case of Australia
Australia is at the forefront of the consequences of climate change. The country has experienced every extreme weather event over the last few years including flooding from precipitation in excess of the norm tp prolonged heat waves and drought conditions leading to firestorms.
The cities of Australia are already feeling the scarcity of freshwater with acute shortages predicted by 2030. Since 2008 Australia has been closely monitoring water usage for agriculture and urban centres. By imposing severe limits on water use, increasing household water charges, developing reverse osmosis desalinization plants, investing in new farm irrigation technology and pipelines to eliminate leaks, $10 billion have led to a 40% reduction in urban freshwater consumption.
Already the driest continent and country in the world, Australia has more to lose than most as climate change alters rainfall and temperature patterns.
The Future of Agricultural Water Management
Climate change is one of a number of drivers that is altering farming practices and leading to dramatic proposals to shift freshwater from where it falls and collects today to where farming and urban centres are and will be located in the future.
Among the solutions are the following:
An Update to this posting:
In this blog I talked about methods for extracting water from the air. One of these ideas has recently received the James Dyson Award.
The technology is called Airdrop, developed by an Australian industrial designer Edward Linacre. Inspired by studying the way the Namibian Beetle survives in that desert by collecting water from early morning dew using its hydrophilic skin, Linacre designed a low-tech solution that extracts water molecules form the air by lowering its temperature so that condensation occurs.
The technology is inexpensive to implement and can be scaled for domestic or large-scale agricultural use. Using a turbine driven by wind, solar power or another external power source, warm air is driven underground. When the air reaches a depth of 2 metres (6.5 feet) the surrounding soil’s cooler temperatures (5C or 9 F degrees) causes the water in the air to condense.
Airdrop uses copper coils as the condensation medium. The water is collected in an underground storage tank and is then pumped underground to plants using subsurface drip irrigation. The Airdrop requires very little power to operate.
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