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Methane emissions in agriculture

  Mar 18, 2020

Methane emissions in agriculture

Is methane a greenhouse gas?

Methane is a greenhouse gas that is 32 times more potent than CO2 over a 100-year time period. Methane emissions from agriculture have increased.

What are the major sources of methane emissions from land?

The major sources of methane emissions from land are currently “ruminants and the expansion of rice cultivation”.

“Ruminants” are animals that have specialised stomach bacteria capable of digesting tough and fibrous material such as grass. The digestive process causes the animals to belch out methane. The most commonly reared ruminants are beef and dairy cows.

Livestock production is currently responsible for around 33% of global methane emissions and for 66% of agricultural methane.

Asia is the region that produces the most methane from livestock production, the report adds. The region accounts for 37% of livestock methane emissions and gases from the region have been growing at about 2% every year since 2000.

Rice farming causes methane release when the crop is grown in flooded paddies (water logged fields). In flooded conditions, water can become “anoxic” – depleted of oxygen – which causes the bacteria that break down plant matter to produce methane. Rice emissions are responsible for about 24% of agricultural methane emissions – and 89% of emissions come from Asia.

Any other source?

Other smaller sources of land methane emissions include animal manure, waste burning and peatlands in the northern hemisphere. 

Where does nitrous oxide emissions come from within agriculture?

Nitrous oxide emissions from agriculture have almost doubled since the 1960s. Nitrous oxide is a short-lived but potent greenhouse gas; one tonne of nitrous oxide is equivalent to 265 tonnes of CO2 over a 100-year time period.

Nearly two-thirds of the world’s nitrous oxide emissions come from agriculture, the report says. Most of these emissions come from the application of nitrogen fertiliser, the report says. Fertiliser application on crops has increased nine-fold worldwide since 1960s.

What does the report say about drylands and desertification?

The IPCC land report says that desertification is not “equated to desert expansion”, but “represents all forms and levels of land degradation occurring in drylands”.

What are drylands?

Drylands encompass parts of the world that are defined as dry sub-humid, semi-arid, arid or hyper-arid.

How important are they?

Dry lands are home to approximately 38% of the global population. Dryland populations are highly vulnerable to desertification and climate change, because their livelihoods are predominantly dependent on agriculture; one of the sectors most susceptible to climate change.

Drylands are particularly vulnerable to land degradation because of scarce and variable rainfall as well as poor soil fertility.

How is climate change impacting on drylands?

Range and intensity of desertification has increased in some dryland areas over the past several decades. Warming trends over drylands are twice the global average. Some temperate drylands are projected to convert to subtropical drylands as a result of an increased drought frequency causing reduced soil moisture availability in the growing season.

Global warming is projected to reduce crop yields across dryland areas, potentially reducing local production of food and feed, the report says. Without concomitant increases in agricultural What is desertification?

productivity and reductions in food waste and loss, meeting growing food demand will thus likely require expansion of farmland into ever-more marginal areas.

What is United Nations Convention to Combat Desertification(UNCCD)?

In 1994, the UN established the United Nations Convention to Combat Desertification (UNCCD) as the “sole legally binding international agreement linking environment and development to sustainable land management”. The Convention itself was a response to a call at the UN Earth Summit in Rio de Janeiro in 1992 to hold negotiations for an international legal agreement on desertification.

What is Desertification?

Desertification does not mean the literal expansion of deserts; it is a broad term for land degradation in water-scarce parts of the world. This degradation includes the temporary or permanent decline in quality of soil, vegetation, water resources or wildlife, for example. It also includes the deterioration of the economic productivity of the land – such as the ability to farm the land for commercial or subsistence purposes.

Why are we worried about desertification?

Desertification has been described as “the greatest environmental challenge of our time” and climate change is making it worse.The combined impact of climate change, land mismanagement and unsustainable freshwater use has seen the world’s water-scarce regions increasingly degraded. This leaves their soils less able to support crops, livestock and wildlife.

How is desertification caused?

Desertification results from various factors, including climatic variations and human activities.

The direct causes of desertification can be broadly divided between land is mismanagement and those relating to the climate. The former includes factors such as deforestation, overgrazing of livestock, over-cultivation of crops and inappropriate irrigation; the latter includes global warming as a result of human-caused greenhouse gas emissions.

How is it impacting India?

Increasing desertification of India’s soil  is a fundamental threat to agriculture.

Of India's total geographical area of 328.72 million hectares (MHA), 96.4 MHA is under desertification. In eight states—Rajasthan, Delhi, Goa, Maharashtra, Jharkhand, Nagaland, Tripura and Himachal Pradesh—around 40 to 70 per cent of land has undergone desertification. 26 of 29 Indian states have reported an increase in the area undergoing desertification in the past 10 years. 

Desertification is defined as “a type of land degradation in which a relatively dry land region becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife.”

Loss of soil cover, mainly due to rainfall and surface runoff, is one of the biggest reasons for desertification. It is responsible for 10.98 per cent of desertification in the country. Water erosion is observed in both hot and cold desert areas, across various land covers and with varying levels of severity. The next big reason is wind erosion.

What is the government doing? 

India will be hosting the fourteenth session of Conference of Parties (COP - 14) from 29th August – 14thSeptember 2019.

Various schemes have been launched by the Government of India such as: Soil Health Card Scheme, Soil Health Management Scheme, Pradhan Mantri Krishi Sinchayee Yojna (PKSY), Per Drop More Crop, etc. which are helping to reduce land degradation. 

What is Atal Bhujal Yojana (ABHY)?

Atal Bhujal Yojana (ABHY), aims at sustainable management of ground water with community participation. The identified over-exploited (OE) and water stressed areas for the implementation of the scheme fall in the States of Gujarat, Haryana, Karnataka, Madhya Pradesh, Maharashtra, Rajasthan and Uttar Pradesh. Nine blocks of Bundelkhand region in Madhya Pradesh viz. Chhatarpur (Chhatarpur district), Naugaon (Chhatarpur district), Rajnagar (Chhatarpur district), Sagar (Sagar district), Niwari (Tikamgarh district), Baldeogarh (Tikamgarh district), Palera (Tikamgarh district), Patheria (Damoh district) and Ajeygarh (Panna district) have been identified in the scheme.

ABHY envisages active participation of the communities in various activities such as formation of ‘Water User Associations’, monitoring and disseminating ground water data, water budgeting, preparation & implementation of Gram-panchayat-wise water security plans and Information education and communication (IEC) activities related to sustainable ground water management.