Smallholder Farmers, Fertilizers, and Increased Food Demand - Soil Management of Smallholder Agriculture - page 51

Despite agriculture's diminishing impact on the region's GDP, it is estimated that
87% of the world's 500 million small farms are in Asia, with China and India account-
ing for 193 and 93 million small farms, respectively (Hazell et al. 2007). Three other
countries (Bangladesh, Indonesia, and Vietnam) have 10 million or more small farms
each, as part of a strong agriculture sector. These small farms (including most <2 ha in
size) contribute significantly to agricultural production, food security, and rural poverty
reduction. Recent research (UN ESCAP 2012) indicated that improving agricultural
productivity in the region could pull an additional 200 million people out of poverty by
attracting private sector investment to supporting agribusiness-related industries.
In recent years, the productivity growth of staple food crops, such as rice ( Oryza
sativa ) and wheat, has declined significantly. For example, rice yield growth in the irri-
gated areas declined from 2.31% per annum during 1970-1990 to 0.79% per annum
during 1990-2000 (Bhandari et al. 2003; Pingali et al. 1997). A major reason for this
decline is the displacement of cereals on better lands by more profitable fruits and veg-
etables. Other reasons include diminishing returns for modern varieties when fertilizers
and irrigation use are already at high levels, low prices of cereals relative to other crops
and input costs, pests and disease, and degradation of soil and water (Pingali et al. 1997),
all of which make additional intensification less profitable (Thapa and Gaiha 2011).
3.4 IMPROVED NUTRIENT MANAGEMENT PRACTICES—
IFDC EXPERIENCES WITH SMALLHOLDERS IN
SUB- SAHARAN AFRICA AND SOUTH AND EAST ASIA
As smallholders in developing regions grapple with feeding and providing family
livelihoods, any desire to transition to sustainable, intensive agriculture requires that
they react to food demand driven by the increasing urban population. In general,
urbanization leads to dietary preferences that include more protein, fruits and veg-
etables, and cereal and grain crops that are more easily prepared food (i.e., rice).
As in the Green Revolution, fertilizers will continue to play a central and vital
role in meeting this increased demand; however, this time, there is additional interest
beyond yield gains. Fertilizer will need to improve the nutritional value of crops and
be used at the proper application rate to avoid underuse of nutrients in most of SSA,
and overuse or unbalanced use in many countries of South Asia. Important to meet-
ing this changing demand is the need for identification, promotion, and adoption of
technologies that enhance food security, are economically and environmental sus-
tainable, and exhibit resilience in the face of global threats such as climate change,
land and water degradation, and increasing competition for finite natural resources.
Addressing these challenges will require interventions in many areas, including,
most important, maintenance and/or restoration of soil fertility.
3.4.1 i ntegrateD s oil F fertility m anagement in s ub -s aharan a Frica
Soil fertility degradation owing to nutrient mining has been identified as the single
most important constraint to food security in SSA. While a large proportion of the
soils have inherently low fertility, the major cause of soil fertility decline is the nega-
tive nutrient balances that occur when crops remove more nutrients than are supplied