Agriculture Reference
In-Depth Information
Chapter 12
Enironmental impacts of organic farming
Nadja Kasperczyk* and Karlheinz Knickel, Institute for Rural Development Research, Johann
Wolfgang Goethe University, Germany
*Ms Nadja Kasperczyk, Institute for Rural Development Research, Johann Wolfgang Goethe University, Zeppelinallee 31,
Frankfurt am Main 60325, Germany. Tel: +49 069 775001, Fax: +49 069 777784, Email: kasperczyk@ifls.de
Introduction
A high proportion of the Earth's land surface has been transformed by direct human action,
with significant consequences for biodiversity, nutrient cycling, soil structure and biology, and
climate. Agriculturally used land accounts for 38% of the world's total land area, of which 69%
is permanent pasture, making it the leading type of
agricultural
land
use
; 28% is arable land
and 3% is under permanent crops (FAO 2004).
The location and physical production conditions are important determinants of the types
and intensities of agricultural land use; in particular, the management of relatively f flat, fertile
land has often been progressively intensified, with mechanisation leading to increased field
sizes, removal of boundary vegetation and increased application of agrochemicals. In contrast,
traditional farming systems on marginal land, where possibilities for mechanisation are
limited because of steep or inaccessible terrain, are in many areas under considerable economic
pressure or have been abandoned already.
The term 'organic agriculture' used in this chapter is based on the Codex definition of the
FAO (1999, see
Chapter
1
). According to Parrott and Marsden (2002) organic agriculture,
which relies on natural methods of building soil fertility and controlling pests and diseases,
can be divided into two categories: certified organic farming and
de
facto
organic farming.
Whereas certified organic production is often oriented towards the market for food labelled as
organic, the latter may represent the major part of organically managed land. Such
de
facto
organic farming can often be found in resource-poor and/or agriculturally marginal regions
where local populations have a limited engagement with the cash economy. This includes many
traditional farming systems found in developing countries, which have evolved through cen-
turies to create agricultural systems adapted to local environmental and cultural conditions
(Parrott and Marsden 2002; Scialabba and Hattam 2002). This chapter covers the environ-
mental impacts of organic farming in this wider sense and also includes agroforestry, a man-
agement system that integrates trees in the agricultural landscape and that is systematically
applied in organic agriculture. Agroforestry is practiced in all agroclimatic zones but is most
prevalent in the tropical belt (Kotschi and Müller-Sämann 2004).
Organic agriculture is generally perceived as a form of agriculture that is more favourable
for the environment than conventional agriculture. In this chapter it is asked where, precisely,
the differences are in environmental terms and whether the available empirical evidence allows
for a generalisation. Geographical differences and interrelationships are emphasised wherever
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