Conservation Comment: The new ag - look to Africa

The Serengeti's still-intact original grasslands may hold the key to a better and more environmentally-friendly way for New Zealanders to raise grazing animals. Photo / file

I would like to give you more examples from Drawdown, edited by Paul Howken.

These systems not only "draw down" CO2 out of the air, but many of the systems give better farming results as well. These systems are being used around the world today.

Net rainfall is increasing in the world, but not in the way it is wanted or needed.

Global warming is creating rainfall patterns that range from prolonged drought conditions to overwhelming rains and flash floods. This makes it difficult to grow annual crops, but there are tropical staple trees that can do well in these circumstances.

For example, an enset tree can go dormant for six to eight dry years. When the rain returns, the enset returns as well. Africa abounds with staple tree crops: baobob, mafura, argan, mongonga, marula, dika, monkey orange, moringa, safou and more.

Some are fruiting, some produce cereal crops.

Maybe some would grow here. Staple tree crops can take root in forest farms, multi-strata agro-forestry or tree inter-cropping systems.

In many cases they can reverse erosion and runoff and create higher infiltration rates for rainwater. Some like arid conditions, steep slopes and a wide range of soils.

The yield is 2.4 times higher than annual staples and they require less fuel, fertiliser and pesticide.

There is also an article on managed grazing:

In the Serengeti, where original grasslands are still intact, they are abundant lands with carbon-rich soil 10 feet deep.

The migrating herds eat grass, herbs and weeds down to the crown. They eat some trees as far as they can reach, and manure the land. Then they move on, and return to lush crops next year ... Put those animals behind a fence, and it is a whole different story — the result is usually unending desert land

Worse still, place cattle in a feedlot and measure their impact on the environment and climate — they rank with coal as being one of the greatest detriments to the planet.

With a changing erratic weather pattern, maybe New Zealand could try a version of the Serengeti system. If the weather is warm and damp, then the pasture only needs a month to recover. If it is colder, or hotter, and drier then it may take a year to recover.

Trees are also an integral component of this system, so perhaps NZ could try some of the tropical trees listed above. Together with trees that provide feed for animals as well — the lucerne tree, bamboo, willow and some acacias.

Some information is very hopeful. Electric vehicles are four times as efficient as gas-powered ones, and when powered by wind turbines at today's prices, the electrical equivalent of gasolene is 30 to 50 cents per gallon. When people were tied to horse-drawn transport, it would have been impossible to imagine how the world would change with coal and oil technology. I hope the same will one day be said of this civilisation.

Sara Dickon is a member of NCWNZ, UNANZ Whanganui, and a founder member Sustainable Whanganui