Agriculture Reference
In-Depth Information
(UN General Assembly
1948
). Hence, freedom from hunger is a fundamental
human right. Alas, the most recent estimates of the Food and Agriculture Organi-
zation of the United Nations (FAO) indicate that, even though the proportion of the
world's population suffering from undernourishment has declined to 12.5 %,
868 million people still remain undernourished in terms of energy intake, most of
them in rural areas of poor countries. Besides, an estimated two billion people
suffer from one or more micronutrient deficiencies (FAO Report
2013
). Further-
more, considering the pace of human populations, which is likely to reach 7.4
billion by 2017 and 9.3 billion in 2050 (FAO Report
2005
), there is an urgent need
to increase food production by at least 50 % in the next 20 years. To overcome
hunger problems around the world, agriculture has traditionally played a funda-
mental role in producing food and generating income. Since 1947, significant
improvements in agriculture technologies have unleashed processes of productivity
growth, economic development, and social transformation, which are witnessed all
around the world (FAO Report
2013
). However, there is still much to do and
agriculture in this context can contribute further to eradicate the malnutrition
problems.
In the mountainous regions of the developing world, agriculture faces several
major challenges. Two of them are of particular importance: (1) a dramatic growth
in mountain populations which is causing an unprecedented pressure on natural
resources and (2) an accentuated demand on commercial products (crops and
livestock) that intensifies the rapid resource use to ensure high productivities.
However, for enhancing the production of many mountain crops, either there are
no improved technologies available or, even if available, they are not affordable to
small farmers. Because of these and some other related problems like deforestation,
soil erosion, and frequent, excessive, and non-judicious use of chemical fertilizers
and pesticides, there is greater pressure on land resources, some of which may have
been damaged irreversibly (Johda et al.
1992
). When considering agriculture in
mountainous regions, special attention must be paid to two fundamental aspects: the
climatic context, mainly characterized by low soil and atmospheric temperatures
especially during the winter months, and the fertility of soils, which is generally low
to very low. Indeed, the soils of many mountainous regions of the world are acidic
and severely nutrient limited. Of the most important macronutrients for plant
growth, phosphorus (P) can be either “occluded” within or else strongly fixed at
the surface of soil minerals like Fe and Al hydrous oxides (sesquioxides). Free Al
and Fe cations react readily with inorganic forms of P, leading to relatively
insoluble precipitates. This reversible process is known as “P fixation” (Johnson
and Loeppert
2006
). Additionally, intensive weathering of soils removes nutrient
cations and leaves behind more stable materials rich in Fe and Al oxides. Besides,
human intervention on soils through fertilization, irrigation, and long-term
monocropping contributes to increased land degradation and loss of productivity
(Tilman et al.
2002
). In the following section, two distant mountainous regions of
the world, yet sharing striking similarities and challenges when considering their
agricultural productivity, are highlighted.
