Agriculture Reference
In-Depth Information
is continually improving, resulting in higher light intensity, higher efficiency and
lower costs.
Water pollution as a result of inorganic fertiliser contamination remains a con-
siderable impact within greenhouse horticulture. Bergstrand (
2010
) found that the
use of closed irrigation systems with biological filtration can reduce the use of water
and fertilisers by between 25 and 40 %. Microflora populations in a filtration system
can also produce biosurfactants, providing control for zoosporic pathogens such as
Phytophthora species.
Land
With pressure to increase agricultural land to feed a growing global population and
the overall quality of those agricultural lands and soils decreasing, horticultural
producers have to strike a delicate balance in coming years. As a large carbon sink,
soil has an important role to play in climate mitigation and therefore strategies to
support this status are vital. Soil is most at risk from nutrient depletion and erosion
when no crop cover exists, therefore a continuous cover crop will go some way to
protect soil structure, texture and fertility. The residue of horticultural crops that
have been harvested should be left in the ground during a usual fallow period, pro-
viding bird habitat, weed and insect control until replanting. Ramos et al. (
2010
) list
a number of benefits to cover cropping which includes holding the soil with root
systems, increasing soil organic matter, improving soil aggregation and increased
microbial activity. Conservation or low soil tillage is another method that preserves
soil nutrients and organic matter from exposure to erosion and depletion.
An important method to protect soil within horticulture is to reduce the depen-
dency on inorganic fertilisers which artificially alter soil composition and contrib-
ute to longer-term soil degradation and reduced natural fertility. Another alternative
technology includes rotation cropping, in which crops extract differing quantities
of macro and micro-nutrients at different stages, allowing natural build-up of im-
portant nutrients. An additional advantage is biological pest and disease control, in
which the life cycle of certain pests and pathogens are broken and future outbreak
problems reduced.
Water
Water is a vital resource to horticultural production and the security of supply across
the global is decreasing. Many current irrigation methods are inefficient. It is esti-
mated that only half of total water withdrawal is utilised by the intended crop, the
remainder being wasted along the delivery from abstraction to the crop (Knox et al.
2012
). Horticulture producers must overcome these challenges to remain profitable
in the future (Anon
2003
). This can be done by reducing dependence on mains
water supply, improving greywater recycling and increasing irrigation efficiency.
