'Conventional plough could contribute to famine'

Photo: Cross Slot no tillage drill

A New Zealand agricultural scientist slash machinery manufacturer claims conventional ploughing could contribute to famine because it causes high rates of carbon loss from soil.


Dr John Baker, has a MAgrSc in soil science and a PH.D in agricultural engineering, which these days are mainly deployed in the manufacture and sales of his Cross Slot no-tillage seed drills. His 'famine' claim is stretching it, and he obviously has a vested interest in this, however, he makes a valid point about carbon loss.


He says carbon is lost to the atmosphere through conventional ploughing and that studies show 15-20% of CO2 in the atmosphere comes from annual ploughing.


Vital ingredient
Carbon is a vital ingredient of soil, Baker notes. Plants that we eat all contain carbon. When they die they decompose and earthworms and other microbes take the products of decomposition, which are rich in carbon, into the soil and keep them there. Fair enough.


“When the soil is ploughed it releases much of the carbon back into the atmosphere. The long term result is a reduction in soil organic matter, which in turn leads to soil erosion, dust storms and ultimately famine,” Dr Baker says.


“Ploughing takes away the food sources of microbes that hold the soil together. Organic matter also stores water and the loss of both decreases the crop yields.”


Key-hole surgery
After 30 years of research at Massey University, Dr Baker researched and developed Cross Slot no-tillage drills which penetrate through crop residue on top of the ground and simultaneously sow seed and fertiliser in adjacent bands.


The no tillage process causes minimal or low disturbance to the soil, traps the humidity, preserves the micro-organisms and soil life and largely prevents carbon from escaping into the atmosphere. Further, by leaving the stubble and straw from the previous crop to decompose on the surface of the ground, it helps sequester new carbon into the soil. 


Food Prize
This year Dr Baker was nominated for the World Food Prize, which was announced last month at the State Department in Washington. Someone is taking his no tillage message seriously.


He points out it’s incredibly important for the soil to gain and trap carbon “if we’re to feed the 50% extra population in the world by the year 2050.”


“Only four percent of the world’s surface has arable soil and we have to learn to farm it sustainably which we simply haven’t been doing. That means no-tillage must replace ploughing as the mainstream food production technique.”


Fuel costs: a net gain
Dr Baker also claims no-tillage saves up to 80% of a farmer’s fuel costs in establishing crops and pastures. Typically no tillage drills are harder to pull through the ground and therefore require a more powerful (and less fuel efficient) tractor. However, no tillage requires fewer passes by the tractor; Baker says farmers typically use 50 to 90 liters of diesel per hectare during the multiple times required to establish a crop. By comparison no-tillage uses “10-20 liters per hectare”.


Dr Baker says that New Zealand farmers sow about one million hectares of new seeds each year. Recent Massey University research suggests that if low-disturbance no-tillage was used universally to sow these seeds it would result in about 1.5 million tonnes less CO2 discharged into the atmosphere annually.

Crop Prospects and Food Situation released

FAO today forecast that 2012 world wheat production will be the second highest on record at 690 million tonnes and also announced that  international food prices rose one percent in February —  the second increase in two months. 

Published today, FAO’s quarterly Crop Prospects and Food Situation report forecast a 2012 wheat crop 10 million tonnes or 1.4 percent down from the record 2011 harvest but still well above the average of the past five years. 

Although plantings have increased or are forecast to increase in many countries this year in response to continuing strong prices, a return to normal yields is expected in areas where record highs were achieved last year, the report said. But it was still too early for a global forecast of 2012 cereal output, it added.

Impact of cold weather

Crop Prospects also noted a firming of  international cereal prices in recent weeks due to tightening current wheat supplies and concerns over the impact of severe cold weather in Europe and the Commonwealth of Independent States.

Turning to the situation at regional level, the report said that adverse weather in West Africa caused a sharp drop in cereal and pasture production in large parts of the Sahel. This, combined with high food prices and civil strife, has led to high food insecurity and increased malnutrition in several countries, notably in Niger, Chad, Mauritania, Mali and Burkina Faso.

In the Near East, food security has deteriorated in the Syrian Arab Republic and Yemen following civil conflict in the two countries. In Syria about 1.4 million people have become food insecure while thousands of families have been forced to flee their homes in Yemen.

In Eastern Africa, despite some improvement, the food situation of vulnerable groups remains precarious, especially in pastoral areas affected by earlier drought. The food security situation in the Sudan and South Sudan is of concern following poor harvests. 

In Southern Africa, overall crop prospects remain satisfactory despite dry spells and cyclones in some areas.

Gains in India

In Far East Asia, prospects for the 2012 wheat crop are generally favourable with output expected to reach last year’s record level due in particular to good gains in India.

In Central America, dry weather reduced plantings of the 2012 secondary maize crop in Mexico.Elsewhere, good  maize harvests are estimated despite  losses due to torrential rains during the recently concluded secondary seasons.

In South America, a prolonged dry spell affected the 2012 maize crop in Argentina and Brazil but above-average outputs are still forecast due to increased plantings.