Agriculture Reference
In-Depth Information
and leaf orientation are used because of their contribution to ecological crop protection (see
Chapters
3
and
5
). Research and commercial opportunities exist for producing new lines of
organic seed varieties. Several large European seed companies have begun marketing organic
seed; however, several small organic seed merchants have also become established where local
demand for organic seed has made it viable (Neeson and Howell 2003). One step down the
supply chain is seedling production, mostly for use on organic herb and vegetable farms. This
sector of the conventional nursery industry is highly regulated and mechanised and therefore
very cost efficient. Modifying such systems to suit organic methods, or developing alternative
methods, is a priority because of the planned ending of derogation rules that allow organic
growers to use conventional inputs when suitable organic supplies do not exist (Pearce
et
al
.
2000, Greer 2002, White 2005). The recent growth in the organic seed and seedling sector
indicates the f flow-on demand along the supply chain from farmers seeking local cultivars
suited to organic conditions (see
Chapter
5
).
Livestock, especially cattle, have a long and essential part in the history of organic
farming (Lampkin 1990). Their ability to perform cost-effective multiple functions is world
renowned for draught, weeding, milk, hides, meat and several types of organic fertiliser,
such as manure and blood-and-bone. Unlike crops, animals are not simply components of a
farming system. Animals are also sentient creatures and therefore can be expected to have
certain moral rights (see
Chapter
7
). In biodynamic agriculture, the cow has a special place
as provider of horns and other organs in the manufacture of various compost-based and
manure-based soil conditioners (see
Special
topic
2
). Although organic principles recognise
the importance of having a natural life, natural living does not automatically imply good
welfare. Key health and nutrition requirements also need to be met. Nevertheless, organic
animals have similar health and welfare experiences compared to conventionally managed
animals (see
Chapter
8
).
The role of catchments (or watersheds) in providing ecological services to agriculture has
often been underrecognised, although there is growing interest among mainstream research-
ers in evaluating methods of integrating farmland, natural vegetation, water bodies and other
landscape features (Stirzaker
et
al
. 2000, van de Ven
et
al
. 2003). In addition to work on the
ecological services provided by diverse landscapes (see
Chapter
4
), research on systems design
has investigated perennial systems, farm layout, crop rotations, water management and so on
(Doing 1997, Kuiper 1997, Vereijken
et
al
. 1997, see also
Chapter
1
). In many cases, the issue of
adoption is a concern, especially if compliance is complex or costly, or where the benefits are
difficult to discern (Ridley 2005).
Soil biology and microbial ecology
The importance of biology in maintaining soil health and fertility has always been appreciated
by the organic movement. It is one of the most fundamental aspects of how soil is conceptual-
ised in organic agriculture (IFOAM 2002). For many years this was a key feature distinguish-
ing organic farming from conventional farming, where the latter system was almost entirely
focused on chemical and physical properties of soil (see
Chapter
2
). However, with growing
interest in the biological aspects of soil fertility, there are technologies available that can help
measure biological activities and composition and these tools are very useful for evaluating the
performance of different farming systems or different treatments within a farming system.
Studies in molecular microbiology and soil microbial diversity have the potential to improve
our understanding of complex nutrient cycles (see
Chapter
2
). Analytical techniques using, for
example, phospholipid fatty acids and substrate-induced respiration provide the ability to
study microbial community structures and population dynamics, factors that can be related to
soil properties such as nutrient availability, structure and pathogenicity (Carpenter-Boggs
et
al
. 2000b, Svensson and Pell 2001, Harris 2003, Steenwerth
et
al
. 2003).
