What are the environmental benefits of organic agriculture?
Sustainability over the long term:-
Many changes observed in the environment are long term, occurring
slowly over time. Organic agriculture considers the medium- and
long-term effect of agricultural interventions on the agro-ecosystem. It
aims to produce food while establishing an ecological balance to
prevent soil fertility or pest problems. Organic agriculture takes a
proactive approach as opposed to treating problems after they emerge.
Soil:-
Soil:-
Soil building practices such as crop rotations, inter-cropping,
symbiotic associations, cover crops, organic fertilizers and minimum
tillage are central to organic practices. These encourage soil fauna and
flora, improving soil formation and structure and creating more stable
systems. In turn, nutrient and energy cycling is increased and the
retentive abilities of the soil for nutrients and water are enhanced,
compensating for the non-use of mineral fertilizers. Such management
techniques also play an important role in soil erosion control. The
length of time that the soil is exposed to erosive forces is decreased,
soil biodiversity is increased, and nutrient losses are reduced, helping
to maintain and enhance soil productivity. Crop export of nutrients is
usually compensated by farm-derived renewable resources but it is
sometimes necessary to supplement organic soils with potassium,
phosphate, calcium, magnesium and trace elements from external sources.
Water:-
Water:-
In many agriculture areas, pollution of groundwater courses with
synthetic fertilizers and pesticides is a major problem. As the use of
these is prohibited in organic agriculture, they are replaced by organic
fertilizers (e.g. compost, animal manure, green manure) and through the
use of greater biodiversity (in terms of species cultivated and
permanent vegetation), enhancing soil structure and water infiltration.
Well managed organic systems with better nutrient retentive abilities,
greatly reduce the risk of groundwater pollution. In some areas where
pollution is a real problem, conversion to organic agriculture is highly
encouraged as a restorative measure (e.g. by the Governments of France
and Germany).
Air and climate change:-
Air and climate change:-
Organic
agriculture reduces non-renewable energy use by decreasing agrochemical
needs (these require high quantities of fossil fuel to be produced).
Organic agriculture contributes to mitigating the greenhouse effect and
global warming through its ability to sequester carbon in the soil. Many
management practices used by organic agriculture (e.g. minimum tillage,
returning crop residues to the soil, the use of cover crops and
rotations, and the greater integration of nitrogen-fixing legumes),
increase the return of carbon to the soil, raising productivity and
favouring carbon storage. A number of studies revealed that soil organic
carbon contents under organic farming are considerably higher. The more
organic carbon is retained in the soil, the more the mitigation
potential of agriculture against climate change is higher. However,
there is much research needed in this field, yet. There is a lack of
data on soil organic carbon for developing countries, with no farm
system comparison data from Africa and Latin America, and only limited
data on soil organic carbon stocks, which is crucial for determining
carbon sequestration rates for farming practices.
Biodiversity:-
Biodiversity:-
Organic farmers are both custodians and users of biodiversity at all
levels. At the gene level, traditional and adapted seeds and breeds are
preferred for their greater resistance to diseases and their resilience
to climatic stress. At the species level, diverse combinations of plants
and animals optimize nutrient and energy cycling for agricultural
production. At the ecosystem level, the maintenance of natural areas
within and around organic fields and absence of chemical inputs create
suitable habitats for wildlife. The frequent use of under-utilized
species (often as rotation crops to build soil fertility) reduces
erosion of agro-biodiversity, creating a healthier gene pool - the basis
for future adaptation. The provision of structures providing food and
shelter, and the lack of pesticide use, attract new or re-colonizing
species to the organic area (both permanent and migratory), including
wild flora and fauna (e.g. birds) and organisms beneficial to the
organic system such as pollinators and pest predators. The number of
studies on organic farming and biodiversity increased significantly
within the last years. A recent study reporting on a meta-analysis of 766 scientific papers concluded that organic farming produces more biodiversity than other farming systems.
No comments:
Post a Comment