Agriculture Reference
In-Depth Information
groundwater is a long-term cumulative process with a timescale of years
to decades.
Public awareness of healthy food products that are free of chemical
additives, along with a worldwide demand to reduce industrial pollution,
has led, in recent years, to the development of organic farming (http//
www.organiccenterewales.org.uk/). Although numerous studies have
questioned organic agriculture's effi ciency (Seufert et al., 2012), sustain-
ability (Trewavas, 2001) and health (Jensen et al., 2012) aspects, organic
food markets seem to be thriving in developed countries, as their output
is perceived by the public to be healthier for both consumers and the en-
vironment. This type of agriculture depends mainly on fertilizers from
biological sources, such as composted animal manure. Nevertheless, mod-
ern agriculture, whether practiced with conventional or organic methods,
needs to reach the goals of mass production, i.e., large quantities and high
quality, to satisfy market demand while maintaining economic standards
of profi tability. This goal is usually achieved through intensive agricul-
ture in greenhouses where irrigation water and fertilizers are implemented
in excess to satisfy crop demand and maximize productivity. In arid and
semi-arid regions, where the climate is warm enough, intensive agricul-
ture in greenhouses operates year round. Moreover, in many of these areas
the agriculture is heavily dependent on groundwater resources for irriga-
tion and therefore its quality is of great importance.
Mass production through intensive organic farming is very similar to
conventional agriculture in its use of agricultural machinery and modern
irrigation techniques; the main differences between the two approaches
lie in fertilization and pest-control methodologies (http://www.epa.gov/
oecaagct/torg.html; EPA, 2013). Unfortunately, the development of in-
tensive agriculture is often associated with the long-term deterioration of
groundwater quality, which is expressed mainly in elevated concentrations
of nitrate and salinity (Vitousek et al., 2009; Burow et al., 2010; Kurtzman
and Scanlon, 2011; Melo et al., 2012; Morari et al., 2012). Groundwater
pollution is usually attributed to a very large array of chemicals. Neverthe-
less, on a global scale the main cause for drinking-water well shutdowns
is a high nitrate concentration in the aquifer water (Osenbruck et al., 2006;
Kourakos et al., 2012; Liao et al., 2012; Kurtzman et al., 2013).
