Skip to main content

Using wastewater to grow crops can address water scarcity in agriculture(downtoearth,)



Judicious use of wastewater to grow crops will help solve water scarcity in the agriculture sector. At a time when we need to produce more food to feed an ever-increasing population, wastewater can be used by farmers either directly through irrigation, and indirectly by recharging aquifers.

Using wastewater in the backdrop of water scarcity due to climate change formed the basis of talks in Berlin during the annual Global Forum for Food and Agriculture.

“…globally, only a small proportion of treated wastewater is being used for agriculture, most of it municipal wastewater. But (an) increasing numbers of countries—Egypt, Jordan, Mexico, Spain and the United States, for example—have been exploring the possibilities as they wrestle with mounting water scarcity,” says Marlos De Souza, senior officer with the Food and Agriculture Organization’s (FAO) land and water division.

Managing a critical resource wisely

Water is vital for food production and climate change threatens this most precious resource. At present, agriculture accounts for 70 per cent of global freshwater withdrawals and more than 90 percent of its consumptive use. Population as well as economic expansion are placing enormous burden on freshwater resources. The overall rate of groundwater withdrawals is steadily increasingly by 1 per cent per year since the 1980s. Over the years, groundwater has been used by farmers to grow crops, resulting in aquifer depletion, groundwater pollution and soil salinisation.

Key facts
Two litres of water are often sufficient for daily drinking purposes but it takes about 3,000 litres to produce the daily food needs of a person
Globally, groundwater provides around 50 per cent of all drinking water and 43 per cent ofall agricultural irrigation
Irrigated agriculture accounts for 20 per cent of the total cultivated land but contributes 40 per cent of the total food produced worldwide
FAO estimates that irrigated land in developing countries will increase by 34 per cent by 2030, but the amount of water used by agriculture will increase by only 14 per cent, thanks to improved irrigation management and practices
A report points out that as water scarcity is growing globally, salinisation, pollution of water courses and bodies and degradation of water-related ecosystems are rising. Large lakes and inland seas are shrinking and wetlands are vanishing.

“Water scarcity is pretty big issue…with increasing population, changing diets and increasing competition for water resources and water services, water scarcity will be more widespread,” Olcay Ünver, deputy director of FAO’s land and water division, says.

In the face of climate change and water scarcity, farmers have to look for alternative ways to grow crops. Wastewater is a valuable and an untapped resource till now in many countries. It can prove beneficial for agriculture, agroforestry and forestry sectors and help achieve food security, but only after it has been properly treated. Wastewater is rich in nutrients, making it a good fertilizer.

Over the years multipurpose dams have often served the needs of the agriculture sector. While potential for building new dams still exists in some regions, most of the suitable sites are already in use and the development of new ones is being increasingly questioned in the face of environmental consequences.

Water scarcity is present in all regions of the world. Around 2 billion people living in the world’s drylands are especially vulnerable to the impacts of climate change, such as drought and water insecurity.

According a FAO expert, for each degree of global warming, an additional seven per cent of the global population will be subject to decreased availability of water resources.

As an adaptive measure, many countries are using wastewater to meet their water needs. In Tunisia, wastewater is being widely used in agroforestry projects, supporting both wood production as well as anti-desertification efforts.

In central Mexico, municipal wastewater has long been used to irrigate crops. In the past, ecological processes helped reduce health risks. More recently, crop restrictions (some crops can be safely grown with wastewater, while others cannot) and the installation of water treatment facilities have been added to the system.

Comments

Popular posts from this blog

SC asks Centre to strike a balance on Rohingya issue (.hindu)

Supreme Court orally indicates that the government should not deport Rohingya “now” as the Centre prevails over it to not record any such views in its formal order, citing “international ramifications”.

The Supreme Court on Friday came close to ordering the government not to deport the Rohingya.

It finally settled on merely observing that a balance should be struck between humanitarian concern for the community and the country's national security and economic interests.

The court was hearing a bunch of petitions, one filed by persons within the Rohingya community, against a proposed move to deport over 40,000 Rohingya refugees. A three-judge Bench, led by Chief Justice of India Dipak Misra, began by orally indicating that the government should not deport Rohingya “now”, but the government prevailed on the court to not pass any formal order, citing “international ramifications”. With this, the status quo continues even though the court gave the community liberty to approach it in …

Cloud seeding

Demonstrating the function of the flare rack that carries silver iodide for cloud-seeding through an aircraft. 
Water is essential for life on the earth. Precipitation from the skies is the only source for it. India and the rest of Asia are dependent on the monsoons for rains. While the South West Monsoon is the main source for India as a whole, Tamil Nadu and coastal areas of South Andhra Pradesh get the benefit of the North East Monsoon, which is just a less dependable beat on the reversal of the South West Monsoon winds.

India’s criminal wastage: over 10 million works under MGNREGA incomplete or abandoned (hindu)

In the last three and half years, the rate of work completion under the Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA) has drastically declined, leading to wastage of public money and leaving villages more prone to drought. This could also be a reason for people moving out of the programme.

At a time when more than one-third of India’s districts are reeling under a drought-like situation due to deficit rainfall, here comes another bad news. The works started under the MGNREGA—close to 80 per cent related to water conservation, irrigation and land development—are increasingly not being completed or in practice, abandoned.

Going by the data (as on October 12) in the Ministry of Rural Development’s website, which tracks progress of MGNREGA through a comprehensive MIS, 10.4 million works have not been completed since April 2014. In the last three and half years, 39.7 million works were started under the programme. Going by the stipulation under the programme, close to 7…