Agriculture Reference
In-Depth Information
The external manifestation of the intensive agroecosystem is a high degree of landscape
urbanization (natural vegetation suppression, sharp land boundaries, the amount of built-up
areas, etc.). At the field level, the typical feature is the stand uniformity, inability to self-
regulation, often poor ability to environmental adaptation, permanent soil erosion and the
need to control other material and energy inputs. Intensive agroecosystems represent a
significant spatial landscape heterogeneity reduction and the corresponding species diversity
decline.
In real-life working, the intensification is achieved in many ways which are often combined.
In particular, the production is narrowly specialised (the number of cultivated plant species
is decreasing to monocultures, with livestock, the specialization goes down to level of
individual category breeding with no ties to the land and crop production).
Significant intensification factors are concentration (production organisms density increase in
time and space), step land use (multistorey stables), high degree of mechanization even
technological processes automation, intensive use of additional chemical inputs, energy and
information.
Highly intensive mechanized system is becoming completely dependent on external inputs
(machinery, fuel, chemicals, seeds). High external energy-material inputs strongly reduce the
systems energy efficiency. The ratio of energy input to energy gained from the crop is up to
3:1 while with non-intensive systems, it is 1:20 and more. Within highly intensive mechanized
livestock production system, the energy balance is even less effective. However, these systems
are very effective in the short term in terms of labour productivity and land utilization.
On the contrary, extensive (low input) farming systems have almost the opposite characteris‐
tics. Their main feature is the external input reduction. Extensive agroecosystems are charac‐
terized by lower energy and material flows per a unit of area and usually higher diversity, less
need for external intervention and greater stability and self-regulatory abilities. They signifi‐
cantly contribute to the conservation of natural resources. Lower inputs can be compensated
by a quality management. Reducing inputs usually brings an agroecosystem production
capacity reduction. Lower yields can be realized at a lower cost without a significant profit
reduction.
In the world, there are extensive farming systems on 80% of the area and on 20%, there are
intensive farming systems. The general trend is the increasing agricultural production
intensification in many developing countries (China, Brazil, Russia,...) and chemical inputs
reduction, respectively their substitution by biological or rational means in developed
countries, especially in the EU. Due to the growing human population and its demands on
sufficient of varied and quality food, a certain degree of agroecosystems intensification is
necessary. However, it is crucial that agroecosystems have a sustainable character.
According to the simple OECD definition, for sustainable agroecosystems, there can be
considered those that meet the needs of these days and do not limit the future generation. The
following definition is more precise:
"Sustainable agroecosystems-agricultural and food systems are
economically viable, meet society's need for food assurance, while they retain and enhance natural
resources and environmental quality for future generations.“
