Impacts of Industrial Agriculture
What has suddenly spurred sustainable agriculture? Why has the agricultural world suddenly become so worried about our farming practices? Lawrence and Walker (2002) summarise the 4 major reasons as to why sustainable agriculture is becoming a favoured alternative:
Monocultures are eroding biodiversity among both plants and animals
Synthetic chemical pesticides and fertilisers are polluting soil, water and the atmosphere.
Soil is degrading and eroding much faster than we can replenish it, reducing fertility and nutrients available.
Water is being consumed at unsustainable rates in many agricultural areas.
Furthermore, the industrial agricultural processes are extremely resource-intensive and depend on expensive inputs from off the farm, generating waste that harm the environment due to the intensive use of fossil fuels. This is considered unsustainable as much of the consumption is of non-renewable resources, and the consumption of some renewable resources is occurring faster than the rate of generation.
There is certainly no doubt, however, that industrial agriculture has been beneficial in supporting our growing population, as it has increased crop yield through using high-yielding plant varieties, mechanisation and synthetic chemical inputs, but these come at a great cost.
But what have these intensive agricultural practices done to impact on our environment? Here I’ll discuss a few major topics concerning the industrial agricultural industry.
The year 1998 saw approximately 137 million metric tons of chemical fertilisers used in agriculture, and the current year will oversee 231 million metric tons of fertiliser in demand which will grow to 253 million tons in 2018, according to the FAO's new world fertiliser report. The extensive use of fertilisers has become a growing concern, and Tilman (1998) suggests that only a third of nitrogen applied as chemical fertiliser is actually absorbed by crops. The remaining two-thirds run off to the environment, and leads to the well-known phenomenon of hypoxia - death of dissolved oxygen - which has been observed in the Mississippi River and its tributaries, forming a ‘dead zone’ (Rabalais et al 1996). Furthermore, chemical fertilisers can increase the acidity of the soil impeding plant growth, therefore affecting biodiversity of ecosystems.
Pesticides also have a major impact on biodiversity, as they can result in bird and beneficial insect populations, disrupting predator-prey balances. For example, Daily (1997) noted that honeybee colonies plummeted from 4.4 million in 1985 to 1.9 million in 1997.
Soil degradation is one of the well-known worries of industrial agriculture and Oldeman et al (1991) suggested that since WWII, poor farming practices had damaged 550 million hectares - 38% of all farmland in use today! The impact on soil health as well should also be considered, as the use of machinery and animal grazing compacts the soil, resulting in soil structure damage and the killing of beneficial organisms in the soil food web . The illustration below taken from the Food and Agriculture Organization of the United Nations links to an interesting larger illustration of the issues regarding sustainable soil management:
With regards to water consumption, agriculture affects water resources in two ways
- Irrigating fields using surface waters or aquifers diverts water from other potential uses
- Farming practices pollute surface waters and aquifers which reduces amount of water available for other uses.
- 70% of pollution seen in US rivers and streams have been blamed by the US Environmental Protection Agency on current farming practices. The Agency also reports that run-off of chemicals, silt and animal waste from US farmland has polluted more than 173,000 miles of waterways (Lawrence & Walker 2002).
And finally, biodiversity, of which agriculture is dependent on, as developing new varieties of plants that keep pace with ever evolving plant diseases is essential for agricultural practices. Industrial agriculture reduces biodiversity through supporting monoculture, which replaces diverse habitats. For example, in the Philippines, more than 80% of farmers now plant modern rice varieties, and this has overseen the extinction of 1,500 local rice varieties in just 15 years (WRI 1992).
But what does sustainable agriculture have to offer in response to industrial agriculture?
Sustainable agricultural systems are generally small-scale, profitable farms that require and use less off-farm inputs. Sustainable agricultural systems also integrate animal and plant production, and where appropriate maintain a higher biotic diversity and make an effort to use renewable forms of energy. Industrial agricultural industries aren't efficient at all - as the average US farm requires 3 kcal of fossil energy to produce 1 kcal of food energy (this also does not include the energy used in transportation!). In response to this, sustainable farms involve less reliance on chemical inputs and involves closer connections between producer and consumer. This is direct marketing on foods to local consumers, with less energy being used in transportation. Articles soon to come will feature present-day case studies of sustainable agricultural systems that have these mechanisms in action, and to note if they're actually beneficial in comparison to industrial agricultural industries.
