Follow the food series
The water challenge
Agriculture uses 70% of all freshwater globally, putting serious pressure on reserves.
Today, Agriculture uses 3 times more water globally than it did 50 years ago – set to
increase by a further 19% by 2050
In recent years, droughts have been longer lasting, more extreme and more
widespread.
o California is one is the largest food producing states in the US, producing more
than 200 different types of crops. With over one third of the country’s
vegetables and two thirds of the country’s fruits and nuts grown in California,
the 2011- -2017 drought cost the industry $US1.9bn annually.
o Irrigation and Water Efficiency board in California are looking into ways of
improving their current irrigation strategies.
80% of Almond production is in California. Traditionally, the majority of
Almond farmers flood their orchards with water at set intervals,
consuming large volumes of water. However, more recently new methods
are being introduced:
Micro drip irrigation – designed to put out the exact amount of water
that a tree needs. The orchards are split into one-acre quadrats, so that
every acre can be irrigated differently through out the season based on
tree growth and water demand. Increased water use efficiency by over
33% in 20 years.
Land Site satellite – can see the changes in the orchard over the seasons
and years and by measuring the change in temperature, you can see if
the canopies are in balance with the rest of the environment around
the trees. The amount of water taken up by the trees is calculated by
using how much moisture is released into the air through
evapotranspiration. By looking at the visible light reflected by this
evaporation, scientists are able to identify not only how cool and well
irrigated the plant is, but also how well the plant is growing. If tree
growth is restricted, fertiliser use, water use can be increased to
increase the tree’s growth. It is hoped that a 10-15% gain in water
productivity can be achieved by harvesting satellite data. More precise
information will allow farmers to use less water, use less nutrients and
improve agricultural management.
Most of the world fail to appreciate water because it is always readily available.
One of the main ways to tackle water challenges is to maximum use of technology to
improve efficiency
, Rice cultivation – Beijing, China:
Rising sea levels is increasing the salinity of freshwater reserves, reducing yields
and slowing the growth of rice. It is such a problem in China, because of their
large coastal area. Rice is very adaptable to various factors such as drought,
salinity stress, and diseases.
The Green Super Rice Projects have brought together over 500 variants of rice to
create hybrids that’s yield or quality is not affected by factors.
Salt – tolerant rice – will be able to be used along China’s coastal area. The salt
tolerant variants are cross bred with high yielding plants, which have high water
and nutrient use efficiency to produce plants which will allow farmers to produce
rice using water more efficiently.
Rice cultivation – Sheffield:
Rice requires 2000-3000 litres of water for cultivation, so is extremely water
consuming. This is because they lose 97% of the water up taken directly through
their stomata.
Sheffield researchers are creating plants with fewer stomata through traditional
plant breeding techniques and genetic modification.
Reduction of the number of stomata will hopefully reduce the water requirement of
rice, increasing water efficiency and making it drought tolerant.
20% of rice production is being affected by drought conditions. Drought tolerant
plants are currently being trialled in the Philippines and Thailand.
Sustainable Food Systems
World Bank along with several of the world’s wealthiest countries have raised
$US20bn for sustainable development of agriculture. The World Bank are so
concerned because Agriculture contributes to 25% of global emissions: projected to
rise to 70% by 2050 if we do not change our practices.
The most important players in achieving sustainable agriculture are researchers,
transport, storage, producers collaborating with using new, sustainable technologies.
To meet expected food demands of 2050, Agricultural output will need to increase
by an estimated 60%
o However, a decline in productive land, limited freshwater supply and increasingly
fragile climate suggests if agriculture continues the way it is, not enough food
with be produced.
Aerofarms – 70,000 square foot vertical farm has the potential to grow over 500
different crop varieties and produce over £2 million of grains annually. What vertical
farming can grow in one acre, would take 390 acres to grow in traditional farming.
Aerofarms is a hydroponics farm, so does not require soils. Nutrient use is reduced,
since it is supplied directly to the roots and water use can be reduced by up to 90%
(depending on the plant type). 1/3rd of soils globally are degraded, so hydroponic
farming may be a solution to help struggling farmers and to allow soils to regenerate.
Hydroponics farming can grow crops in 12-13 days when it would usually take 30-40
