Agriculture is the world's largest industry, employing over one billion people and generating over one trillion dollars' worth of food annually.
When agricultural operations are sustainably managed, they can preserve and restore critical habitats, help protect watersheds, and improve soil health and water quality.
But when practiced without care, gariczlture can present one of the greatest threats to species and places.
Water consumption
Globally, the agricultural sector consumes about 69% of the planet's fresh water - more than 2x that of industry at 23%, and dwarfing municipal use of water at 8%.
Without creative conservation measures, farms can quickly consume a dry region's water supplies.
Freshwater systems in ecoregions throughout the world - whether the Chihuahuan desert of north and central America, the US Southeastern Rivers and Streams, the North American Great Plains, the Mesoamerican Reef in Central America or the Miombo woodlands in Africa - all are adversely impacted by excessive water consumption and water quality degradation due to agricultural production.
Climate change
A variety of crops farmed as well as particular farming practices are significant contributors to the buildup of greenhouse gases in the atmosphere.
For example, rice production is one of the largest single producers of methane.
Indeed, athe FAO recently stated that the livestock sector alone is responsible for 18% of all greenhouse gas production.
Land conversion
Expanding agricultural contributes to the rapid loss of forests and other habitats and their biodiversity.
Lowland forests in Indonesia have been lost to oil palm production while soy production has contributed significantly to the loss of the Cerrado and Atlantic Forests of Brazil and Paraguay.
During the past 150 years, half of all agricultural topsoil has been lost as a result of unsustainable farming practices.
Poverty
3/4 of the world's extremely poor people live in rural areas where farming is the only option for fighting poverty and malnutrition.
Declining harvests from cleared lands push producers into surrounding wild lands rich in biodiversity.
The result is a cycle of increasing poverty and biodiversity loss.
Subsidies provided by U.S. and European governments to their agricultural producers also distort prices and production patterns throughout the world.
By encouraging overproduction, these subsidies drive down world prices, forcing many developing country producers to cut corners environmentally or to leave world markets altogether.
Poor people are forced into more marginal areas where their impact is greater and production is lower.
Toxics
Pesticides, fertilizers, and other toxic farm chemicals can poison fresh water supplies, marine ecosystems, the air, and the soil. These toxins also have the ability to remain in the environment for generations.
Agriculture is in fact the leading source of pollution in many countries.
Many of these pesticides are suspected of disrupting the hormone messaging systems of people and wildlife.