255.1 Future and Challenges of Dryland Farming
The challenge for global agriculture in the twenty-first century is to produce 70 %
more food and fiber by 2050 for a growing and more prosperous population while
implementing more sustainable methods of farming and responding to climate
change (FAO 2009 ). As incomes rise, people tend to eat fewer grains and increase
their consumption of meat and other animal-based products. Dryland farming areas
must play an important role in meeting this challenge.
Dryland farming areas are largely semiarid and have unique characteristics.
Bowden ( 1979 ) lists four management keys that must be understood and applied as
new strategies and practices are developed:
- No growing season is or will be nearly the same in precipitation amount, kind, or
range, or in temperature average, range, or extremes, as the previous growing
season. Although this is true for all rainfed cropping systems, it requires absolute
attention in dryland farming. Crop cultivation requires adjustment every year,
which leads to the second key. - Crops cannot be planned or managed in the same manner from season to season.
Most of the practices in either humid or arid areas have some predictability on an
annual basis. In semiarid climates, however, even highly mechanized, techni-
cally advanced, commercial farms such as those in the High Plains of North
America or the outback of Western Australia do not have sufficiently stable pro-
duction for the individual or government to count on for a given production fig-
ure for the following season. - Soil and water resources do not remain the same for any extensive period of time
once agriculture is introduced. Most semiarid cropland suitable for cultivation is
developed under grass or scattered shrubs on relatively flat topography. The
competition for water and nutrients to produce crops requires removal of the
protective cover. Because appropriate crops are annual and dependent on pre-
cipitation, severe drought often leaves the soil highly vulnerable to wind
erosion. - There is abundant sunshine due to many cloud-free days. Abundant sunshine
means higher temperatures that induce rapid growth, but it also demands careful
management of soil water. It is possible for a grain crop to mature rapidly due to
several weeks of sun-drenched, rainless conditions and desiccate just days before
ripening. It is also possible for a few millimeters of precipitation to occur at
almost the last moment to produce a good grain crop.
The four key points outlined above have always been challenging, but they are
even more so today in view of the increased environmental concerns and the threat
of climate change. The challenges are to increase resilience and to achieve and
maintain the sustainability of dryland agriculture. The public at large is increasingly
demanding sustainable systems, although their demands are not always clear. There
are many definitions of sustainable systems, sustainable agriculture, sustainability
and other terms that are difficult to interpret and often not feasible to implement.
Dryland Farming: Concept, Origin and Brief History