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Biofuels are fuels made from organic matter. They include liquid fuels such as ethanol, biodiesel, and methanol; gaseous fuels such as methane and carbon monoxide; and solid fuels such as biochar and the more traditional charcoal. Biofuels may have some environmental advantages over gasoline and diesel fuels, but they are more expensive to produce and cannot supply more than a small part of the world's total transportation energy needs. And because they compete with food crops and nature for land, water, and nutrients, expanding the use of biofuels could negatively affect human health and natural ecosystems.
Another land-based concern with biofuels is the inadvertent introduction of invasive species that could negatively impact the natural landscape.
The costs associated with invasive species, even those that are deemed to be beneficial, in most cases, outweigh the benefits that accrue from their use.
No widespread invasive plant species has been controlled through utilization alone in any part of the world.
Industrialized agriculture is one of the most important drivers of environmental degradation worldwide. It has caused large-scale contamination of soil, water and biota, through the extensive use of agro-chemicals, including pesticides and soil amendment products such as fertilizers.
There is increasing concern that micropollution-characterized by low-level, multi-compound exposure-may suffice to elicit critical, potentially hazardous effects on environmental and human health.