Summary

• The human population has grown very rapidly over the last 150 years.

• All populations eventually reach the carrying capacity of their environment when resources begin to run out and the death rate increases.

• The growth of the human population is slowing, but because women are choosing to have fewer children, not due to an increasing death rate.

• It is possible that the human population will overshoot Earth's carrying capacity because resources other than food are also important to human survival and because of demographic momentum.

• Feeding a human population of many billions requires the mass production of food in agricultural systems.

• The addition of water and the removal of competing plants allow plants to maximize light and carbon dioxide uptake.

• Farmers make up for the loss of nutrients from agricultural systems by adding fertilizer.

• Farmers minimize the loss of plants to pests by using cultural control and pesticides.

• The production of hybrid strains and genetic engineering has led to improvements in crop production.

• Fertilizer runs off into waterways, causing human health problems and damage to fish populations.

• Pesticide use continually increases as pests become resistant to them. Persistent pesticides also accumulate in organisms at higher levels of the food web.

• Soil is being lost faster than it is being replaced in many areas through erosion and salinization.

• Planting many crops in an area rather than planting large monocultures can help reduce pest populations by requiring pests to disperse.

• Fertilizer and pesticide use can be minimized through the use of crop rotation and by careful monitoring of the agricultural environment.

• Consumers can help reduce the environmental cost of modern agriculture by accepting a small amount of pest damage on produce, by eating less meat, and by purchasing organically grown products.

Environmental problem

Bioaccumulation of persistent pesticides

Bioaccumulation of persistent pesticides

Eutrophication of surface water and nitrate pollution of groundwater

Reduce number of acres irrigated.

• Increase efficiency of irrigation.

Soil erosion and desertification

Soil erosion and desertification

Loss of habitat for nonhuman species

Solution

■ Minimize monocultural plantings.

■ Reduce use of pesticides.

■ Increase use of integrated pest management.

> Reduce use of inorganic fertilizer.

Reduce number of acres irrigated.

• Increase efficiency of irrigation.

Reduce use of tilling on marginal lands.

Reduce amount of land used for crop production.

■ Minimize the amount of land converted to agricultural production.

Actions we can take

> Accept produce that has superficial pest damage.

> Purchase organic foods.

> Add diversity of foods to our diets to promote polyculture.

> Reduce meat consumption, and thus overall crop production.

> Support policies that reduce use of monocultural production (for example, elimination of price supports for crops).

• Support integrated pest management research. Purchase organic foods.

> Purchase foods grown in polyculture, where crop rotation is employed.

> Reduce meat consumption.

Reduce meat consumption. > Support research and national agricultural policies to reduce agricultural water use.

Reduce meat consumption. • Support research on effective non-chemical means of weed control, and see suggestions below.

Reduce meat consumption.

> Support policies that effectively lead to decreased human population growth rates.

> Support policies that provide developing countries with the tools to increase crop yield sustainably.

Table 15.1 Reducing the environmental impact of modern agriculture. This table summarizes the environmental costs of modern agriculture and the individual and collective actions we can employ to reduce these costs.

Was this article helpful?

0 0
How To Bolster Your Immune System

How To Bolster Your Immune System

All Natural Immune Boosters Proven To Fight Infection, Disease And More. Discover A Natural, Safe Effective Way To Boost Your Immune System Using Ingredients From Your Kitchen Cupboard. The only common sense, no holds barred guide to hit the market today no gimmicks, no pills, just old fashioned common sense remedies to cure colds, influenza, viral infections and more.

Get My Free Audio Book


Post a comment