UN warns of looming threat to food security

A new report by the Food and Agriculture Organisation (FAO) of the United Nations has warned of a growing threat to global food security as a result of severe loss of biodiversity — that is, plants, animals and micro-organisms that contribute to food production.

India is among the countries with a very high threat to soil biodiversity, according to the “State of the World’s Biodiversity for Food and Agriculture” report, released in Rome on February 22.

A risk index was created by combining eight stressors of soil biodiversity, which include loss of above-ground diversity, pollution and nutrient overloading, overgrazing, intensive agriculture, desertification, and climate change among others.

While climate change is a driver for the loss of biodiversity, the latter is critical in building resilience to devastating impacts of climate change, states the report, which for the first time, assessed reports of 91 countries on their biodiversity status.

The global map shows almost all of India falls in the highly stressed zone along with some parts of Africa, Americas and Asia.

The report notes that there is very limited information available on soil biodiversity in Asia but some reports show high microbial biodiversity in the soils of organic farming lands.

“Soil biota is critical for release of nutrients to the crops as well as organic matter formation. With climate change soil biota will be impacted even more and there will be further loss of nutrients causing collapse of agriculture in some places,” said Prof N H Ravindranath, climate scientist from the Indian Institute of Science (IISc), Bengaluru.

The global report also highlights the loss of biological control agents (BCAs) — insects and pests — as an important factor in declining biodiversity. India, in its country report, has noted a decline of parasitoid wasps and parasitoid flies, which play an important role in biological pest control. Bangladesh has reported a decline in spiders and predatory insects in fields; Nepal has mentioned a general decline in the diversity of the natural enemies of pests. The United States has reported a decline of almost 40% in its grassland bird index between 1968 and 2014.

On climate change, the reports of various countries state that extreme weather events are causing major disruptions to species distribution and yields. For example, rising temperatures in the tropics are pushing coffee growing towards higher elevations in mountainous areas.

The ranges of some important pests, such as the coffee berry borer, have also extended to higher elevations – for example in East Africa — prompting coffee farmers to spray pesticides even in highland areas. Frequent cold or windy days in spring can also disrupt pollination process. Egypt has reported that rising temperatures will lead to northwards shifts in the range of fish species, with impacts on fishery production.

Biodiversity in agriculture is crucial to adapting to climate change. India, in its report, has noted that livestock diversity, for example, is a buffer against crop failure.

It says that small land holders and landless rural dwellers manage 75% of livestock resources and obtain nearly half of their income from them.

“Risk can be reduced, for example, by raising species, breeds or varieties that are well adapted to coping with shocks such as droughts or disease outbreaks or by raising a number of different types of crops, livestock or aquatic organisms so as to increase the likelihood that at least some will survive such events,” the report states.

“Before the Green Revolution [of the 1960s], we were growing a large biodiversity of crops on a landscape level. We had different cropping and tree systems at a farm level; multiple crops and multiple varieties of a given crop were grown. Even if there was a failure, all crops would not be affected at the same time,” Ravindranath.

“Now, specialisation of crops for high yields has made farmers vulnerable. Crop failures are common when there is natural disaster or pest attack,” he added.

First Published: Feb 27, 2019 00:02 IST