Soil Conservation

Sustainable Agriculture

Major Agricultural Problems-SOIL Erosion = loss of soil particles due to water and wind

action Over-cultivation = repeated cultivation and crop

growing, faster than soil can regenerate Over-grazing = grazing of grassland faster than it

can be regenerated Deforestation = loss of forest cover Salinization = increase in salt content of the soil,

usually due to improper irrigation practices

DEFORESTATIONDEFORESTATION

Result of Result of overgrazing OR overgrazing OR overcultivationovercultivation

EROSION Results in coarse soils with poor nutrient quality WHY??

Clay and silt particles, along with humus, are removed first therefore water and nutrient-holding capacities are poor

Ultimate result of continued erosion is desertification, which leads to declining productivity on a given plot of land

(You don’t need to know the types of erosion.)

Solutions to Soil Loss Problems Conservation tillage (low or no-till farming) Terracing Contour farming Shelter belts (leave a row of trees around) Agroforestry Strip cropping/polyculture Crop rotation (more for fertility than loss)

NO-TILL NO-TILL FARMINGFARMING

NO-TILL NO-TILL FARMINGFARMING

TERRACINGTERRACING

CONTOUR CONTOUR FARMINGFARMING

IntercroppingIntercropping

IntercroppingIntercropping

AgroforestryAgroforestry

Fertilizers: Animal Manure Green Manure Compost

GREEN OPTIONS for adding nutrients:

Big Picture

Industrial agriculture is cheaper – but the inputs and outputs are not sustainable

Polyculture MORE productive than monoculture – more labor intensive but many ecological benefits, such as?

Increasing food production on one plot of land means another isn’t cleared

Reasons for eating less meat:

More than one third of the world's grain harvest is used to feed industrially-farmed livestock. 1

The total cattle population for the world is approximately 1.3 billion occupying some 24% of the usable land of the planet 2

Some 70 to 80% of grain produced in the United States is fed to livestock 3

Half the water consumed in the U.S. is used to grow grain for cattle feed. 4

A gallon of gasoline is required to produce a pound of grain-fed beef. 5

80 million metric tons of CH4 emitted per year (20% of US CH4 emissions from cows)6

Global Grain Production

Argentina’s Experiment

Eight-year cycle (5-6 cattle, 2-3 corn/wheat/soy)

Polyface FarmShenandoah Valley

Virginia

YouTube - Polyface farm

YouTube - GROWING POWER - Will Allen

Notes on stats: Lester Brown, Michael Renner, Brian Halweil Vital Signs 2000, (World Watch Institute) p.

34; Frances Lappe Moore, Joseph Collins, Peter Rosset, World Hunger: 12 Myths, (Food First and Grove Press, Second Edition, 1998) pp.8, 180; Richard Robbins Global Problems and the Culture of Capitalism (Allyn and Bacon, 1999), p. 220

See for example: United Nations Food And Agriculture Organization statistics database on livestock numbers. Note

the numbers are from 2001. Devinder Sharma also highlights an interesting point that, “Around 1.5 billion marginal farmers in

the developing world live in virtual penury” and yet, “cattle in the industrialised world are reared in luxury, with a cow in the developed world receiving subsidies that amount to almost twice the annual income of an average Third World farmer.” For years, many in the Third World have argued that the North heavily subsidizes and protects it agricultural industry while at the same time telling the poor to liberalize, which has resulted in poverty due to pushing down commoditiy prices and due to lack of market access for the poor. (Above link is from “Western cow vs Southern farmer: The absurdity of inequality”, InfoChangeIndia.org, April 2002)

Also see What Price Beef? by Marguerite Hampton, with a list of many, many stats, including statistics on how much land, water, energy and so on is required to support cattle, and the various effects.

Robbins, p.220; Vandana Shiva, Stolen Harvest (South End Press, 2000), pp. 70-71. Ibid Robbins, p.220 Ibid http://www.darrolshillingburg.com/GardenSite/Images/webImages/3sisters/3sistersMain.jpg http://www.epa.gov/rlep/faq.html