ВУЗ:
Составители:
Рубрика:
were any serious health risks to the remainder of the group, it does indicate that use of organic food and non-
food products can reduce the presence of those products in humans.
With increasing demands for food supplies during the past 60 years, we saw the introduction of the use of
harsh chemicals and synthetic fertilizers as a way for farmers to boost crop yields. This subsequently has been
followed by the more recent adoption of planting genetically modified crops.
Even today, there are toxic and persistent pesticides still used in agriculture. CDC noted that organophos-
phate pesticides account for approximately half of the insecticides used in the United States. An estimated 60
million pounds of organophosphate pesticides are applied to about 60 million acres of U.S. agricultural crops
annually, and an additional 17 million pounds are used per year for nonagricultural uses, such as in household
pest control products and in lawn and garden sprays.
The National Organic Standards Board defines organic agriculture as an ecological production manage-
ment system that promotes and enhances biodiversity, biological cycles and soil biological activity. It is based
on minimal use of off-farm inputs and on management practices that restore, maintain and enhance ecological
harmony.
Despite the fact that less than 1 percent of U.S. agriculture research dollars are spent on organic practices,
organic production has been shown to have yields comparable to, and sometimes higher than, conventional sys-
tems. In addition, because organic production improves soil quality as measured by soil structure, organic mat-
ter, biological activity, water infiltration and water-holding capacity, organic systems generally produce higher
yields than crops grown using conventional high-input methods during drought, leading to production stability
year after year.
Organic agriculture is a collection of tested agricultural practices by diligent farmers intent on preserving
the health of our planet. Organic agriculture is sustainable, keeping soils healthy and alive, and helping to
minimize contamination of the earth’s precious water supplies.
Organophosphates are not allowed in organic agriculture. Instead, organic growers use biological and cul-
tural practices as their first line of defense against pests. Methods used include crop rotation, the selection of
pest- and disease-resistant varieties, nutrient and water management, the provision of habitat for the natural
enemies of pests, and release of beneficial organisms to protect crops from damage. The only pesticides al-
lowed in organic agriculture must be on a USDA approved list, with restricted use.
In addition, organic practices prohibit the use of genetic engineering, irradiation, sewage sludge, antibiot-
ics, and hormones. These practices are allowed in other forms of raising and producing our food, and other ag-
ricultural products.
Because organic agriculture respects the balance of microorganisms in the soil, organic producers use com-
posted manure and other natural materials, as well as crop rotation, to help improve soil fertility, rather than
synthetic fertilizers that can result in an overabundance of nitrogen and phosphorous in the ground. As a result,
organic practices protect ground water supplies and avoid runoff of chemicals that can cause "dead zones" in
larger bodies of water.
Comparisons in Europe, for instance, have shown nitrate-leaching rates on organic farms are 40 – 57 per-
cent lower per hectare (roughly 2.5 acres or 12,000 square yards) and carbon dioxide emissions are 40 – 60 per-
cent lower per hectare than conventional systems.
On the other hand, current conventional practices have led to some measurable problems, including a high
level of toxic metals in commercial fertilizers. An analysis of 29 fertilizers found that each contained 22 differ-
ent heavy metals. In 20 of the products, levels exceeded the limits set on wastes sent to public landfills, with
disturbing quantities of arsenic, lead, mercury, cadmium, chromium, and dioxin, among others.
Furthermore, polluted runoff from farms and cities went largely unabated and actually increased over the
past 30 years according to a 2001 report from the Pew Oceans Commission. The report noted that many of the
nation’s coastal environments exhibit symptoms of over-enrichment from these run-offs. Symptoms include
harmful algal blooms, loss of sea grasses and coral reefs, and serious oxygen depletion. Coastal regions, as a
result, have suffered reduced production of valuable fisheries and threats to biodiversity and ecosystems less
resilient to natural and human influences.
Because organic practices help safeguard the environment and protect habitats, organic production con-
serves and promotes species diversity. In the United Kingdom, a study comparing biodiversity in organic farm-
ing and conventional farming systems found that organic farms had five times as many wild plants in arable
(farmable) fields and 57 percent more species.
The organic farms also had 25 percent more birds at the field edge, 44 percent more in the field in autumn
and winter, and 2.2 times as many breeding skylarks and higher skylark breeding rates. In addition, they had 1.6
times as many of the invertebrate arthropods that make up bird food; three times as many non-pest butterflies
Страницы
- « первая
- ‹ предыдущая
- …
- 37
- 38
- 39
- 40
- 41
- …
- следующая ›
- последняя »
