Forskellige afgrøder giver klimarobusthed

Hedebølge i Californien. Verdens klimakrise har enorme sundhedsmæssige konsekvenser. Alligevel samtænkes Danmarks globale klima- og sundhedsindsats i alt for ringe grad, mener tre  debattører.


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Forfatter billede

I modsætning til monokulturelt landbrug, hvor man kun dyrker en afgrøde, kan “klimasmart” landbrug med adskillige forskellige typer af afgrøder give modstandsdygtighed mod trusler fra klimaforandringer, skriver Worldwatch Institute onsdag.

The loss of arable land due to climate change may amount to as much as 21 percent in South America, 18 percent in Africa, and 11 to 17 percent in Europe, according to scientists at the University of Illinois, Urbana-Champaign, Worlwatch Institute.

The potential of climate change to adversely impact food security in these regions is staggering.

Countries in Asia are also highly vulnerable. In Vietnam, for example, the International Food Policy Research Institute (IFPRI) reports that by 2050, rice yield decreases associated with climate change may amount to 2.7 million tons.

But the loss of arable land is just one of many climate change-related agricultural concerns. Many industrially produced crops are especially vulnerable to extreme weather conditions and the shifting demographics of pathogens.

Researchers from the Consultative Group on International Agriculture Research (CGIAR) assert that the majority of food produced in the world comes from too narrow a range of crops. Furthermore, monocropping—a dominant form of agricultural production—can make plants more vulnerable to weather events and pathogens.

Large monocropped fields are particularly susceptible to pests, diseases, and extreme weather events because their narrow genetic diversity restricts the adaptability of these populations to environmental stressors. Diversifying crops, meanwhile, can increase crop resiliency and simultaneously reduce the need for pesticides.

Many farmers are realizing that they can decrease pesticide use with “climate-smart” agriculture. Maurice Kwadha (pictured above) owns a farm and tree nursery that, while spanning less than half an acre, hosts a wide variety of crops.

Kwadha’s mosaic of tree saplings, corn, bananas, onions, sweet potatoes, and tomatoes, bordered with trees that both replenish soil nutrients and decrease erosion, mitigates the effects of Kenya’s increasingly unpredictable rains and longer, more intense dry spells. As an added benefit, farmers like Kwadha depend less on fertilizers.

The more complex environment that they support also promotes a greater diversity of animals.

A study by Brenda Lin of Australia’s Commonwealth Scientific and Industrial Research Organization (CSIRO) shows that, in addition to increasing the range of crop species, farmers can diversify crops by switching land use practices throughout the year.

In Yasothorn, Thailand, smallholder farmers grow and harvest fruits and vegetables between their rice cultivation cycles. They are finding that diversifying crops leads to a diversified income as well, which can protect farmers amid variable market prices.

The United Nations Food and Agriculture Organization (FAO) and the European Commission recently announced a three-year project promoting, among other things, the diversification of crops as a “climate-smart” agricultural strategy.

With support from large research organizations and food programs around the world, agricultural diversification has the potential to help farmers adapt to the myriad challenges of climate change.

Climate change will shift the landscape of agriculture around the word in the coming years. Will farmers, policymakers, and scientists widely support “climate-smart” strategies in response to this shifting landscape?

The answer to that will come in time, but efforts from smallholder farmers like Kwadha and international bodies like the FAO prove hopeful.

Læs mere her: http://www.worldwatch.org/node/13352