with wheat, so we are producing
more yield per kg of applied nitrogen. The pastures also helped integrating livestock into the farming
operations, which meant more production per unit of land.
The efficiency of wheat production
in the Western Cape, when measured in yield per hectare, has nearly
doubled since 1994. We are producing more wheat on much less
hectares. The question still remains
how can, we be even more ecoefficient than we currently are. We
know that the use of conservation
agricultural practices is the base of
this improvement. We need to fine
tune the systems and that can be
done in three main areas: improving soil health, management and
genetics.
Our management of the cropping
system (planting at the correct
time, using optimal machinery, application timing etc.) is very near to
optimal efficiency, small adjustments can still be done. As more
efficient machinery comes available, the management can be adjusted to include these. Bio-fuel
powered tractors and combines
could play a role in the near future.
The use of aerial drones could help
to improve on-farm management
on-farm even further. The improvements in management for the
most part will be external.
The improvement of soil health and
genetics of crops will probably be
the biggest contributors to improved eco-efficiency within the
grain producing areas of the Western Cape. Research from around
the world supports the improvement of soil health to increase
yields without relying on more and
more external inputs into the system. The increase of the organic
matter content of our soils will be
the key. For every one percent increase in organic matter the carbon
content of the soil increases
(building the moisture storing capacity of the soil), the availability of
nutrients for recycling as well. The
increased infiltration rate and storage capacity of our soil along with
the protection of residue on top of
the soil will thus ensure a more
efficient use of water in producing
yields. An increased nutrient recycling capacity relates to less artificial fertiliser inputs, thus a more
eco-efficient production. Increased
diversity and resilience in our cropping systems might be achieved by
the inclusion of multi-specie cover
crops. Building the resilience of our
systems will decrease the need for
pesticides. All of these improvements will increase the microbial
life in the soil and thus soil health.
The greater the diversity below the
soil the more eco-efficient our production systems will become.
Crop genetics will also play a huge
role in breeding more efficient
plants such as improved yield with
lower amounts of moisture or
higher yields through more effi-
cient use of available nutrients. This
type of improvement is relatively
slow and thus more and more focus is also being placed on the improvement of associations between
plants and the microbial life in the
soil. The important role of mycorrhizal fungi and their association
with plant roots is gaining more
and more interest (the following
article will help shed some light on
this: http://www.pbs.org/wgbh/
nova/next/nature/more-food-withmicrobes/).
New systems research that will focus on several of these improvements will be undertaken at the
Langgewens Research Farm
(between Malmesbury and Moorreesburg) from this coming cropping season (2016) over the next
ten years.
Bibliography
Brian A. Keating, Peter S. Carberry,
Prem S. Bindraban, Senthold Asseng, Holger Meinkee and John
Dixon, 2009. Eco-efficient Agriculture: Concepts, Challenges, and
Opportunities. Crop Science, Vol 50
no 1, pp 109 -119
Dr Johann Strauss
Scientist
Sustainable cropping systems
Directorate Plant Sciences
Western Cape Department of Agriculture
[email protected]
0829073109