Agriculture

Arable Land  There is a decline in the amount of arable land.

Farming  Early farmers used animals to pull plows through soil.  Mixed up soil nutrients  Loosened soil  Uproot weeds  Used organic fertilizers (manure)  Irrigation by digging ditches  Some countries still use old methods, but most update methods.

Fertile Soil  Soil where plants are healthy and grow rapidly.  Most plants grow in topsoil  Contains rock particles, water, air, and decomposed plant and animal matter.  Contains bacteria, fungi, earthworms and insects

Soil Formation  Formed from bedrock  Weathering over thousands of years forms sediment.  Combine with water, air and decayed materials.

Soil Conservation  Contour plowing- plowing across slope of hill.  Plow forms ridges that do not allow excess runoff.  Use of organic fertilizers like compost  No-till farming- after harvest soil is not tilled

Soil Conservation  Prevent salinization- increased salt level in soil.  Improve irrigation methods, increase amount of water to wash out salt.

Farming Methods Jigsaw  Farmers are constantly dealing with soil erosion. Using the information on pgs in your groups complete the following task:  Preparing the Land on 109.  Planting the Land on  Soil Enrichment on  Farms and Human Nutrition on 111

Jigsaw continued  Each number group must:  Read independently and take notes  Meet with other People in number group  Each person creates a poster which summarizes the section visually.  All people in group must cover the same info, but the posters can look different.  Go back to home group and explain your section to the group.

Farming Methods  Soil erosion is a major problem for agriculture.  Farmers develop methods to conserve soil.

Preparing the Land  Traditional tilling use machines to break up soil.  This exposes soil to erosion.  Farmers use conservation tilling.  Disturb topsoil as little as possible.  Loosen soil but not turn it over.  No-till cultivation- drill holes and drop in seeds.  Does require pesticides  Cover surface with Humus using previous crop.

Planting the Land  Many farmers must plant on sloped surface so crops must be planted to prevent erosion from runoff.  Contour farming- plant crops across slope to prevent erosion.  Can decrease erosion 30%-50%

Farming Methods continued  Strip Cropping- rows of crops are planted alternately with rows of grass or legumes.  This protects against erosion and adds nutrients to the soil.  Terracing- crops planted in ridges down a slope like stairs.  Slows down runoff

Soil Enrichment  Soil must be full of nutrients to be productive.  Use organic fertilizers- add multiple nutrients to soil and add to humus.  Do not cause pollution to groundwater.  Crop rotation- changing crops planted year to year.  Each crop uses different nutrients so soil is not depleted.

Integrated Pest Management  A pest is any organism that:  Spreads disease  Destroys properties  Competes for resources  Acts as a nuisance

Pests in the Wild  In undisturbed ecosystems pests are kept in check by predators, but human impact has allowed pest populations to increase by limiting the number of predators.

Pesticides  With increasing pests populations humans needed to use pesticides  Insecticides- kills insects  Herbicides- kills weeds  Nematicides- kills worms  Fungicides- kills fungus  Rodenticides- kills mice and rats

Introduction of IPM  Chemical pesticides are harmful to environment so integrated pest management (IPM) was introduced.  Use mix of traps, disease-resistant plants, organic pesticides and reintroduction of predatory species.

IPM in Practice  Based on a series of decision making steps using a mix of many tools.  6 Steps of IPM  Use pages to identify the 6 steps of IPM and a brief description of how each is done on the handout. Include handout in your notes for this section.

IPM Tactics  Use multiple tactics to keep pest populations off balance and prevent resistance to pesticides.  Based on managing pests not eradicating them.

Methods  Cultural Methods- minimize conditions pests need for life.  Ex- multicropping  Several crops in one field  Diff. for pests to overrun an area.  Physical Methods- preventing pests from entering an area, or forcing them to leave.  Ex- window screens, steel wool

Methods continued  Genetic Methods- use pest resistant plants.  Ex- bioengineered crops, sterile male pest releases, host plant resistance.

Methods continued  Biological Methods- other living things used to limit pest populations.  Parasitoids- insect that develops within a host killing it. Ex- wasps lay eggs in aphids.  Predators- feed off parasites. Ex- beetles feed off mites.  Pathogens- disease that affects pests. Specific to certain insects.  Weed feeders- organisms that feed off weeds.

Methods…again  Chemical Methods- chemical pesticides  Synthetic- work quickly and effectively, but harmful to env.  Biorational- naturally occurring compound.  Env. Friendly but not as quick acting.

Control  Regulatory Control- Government agencies try to limit pest pop. Through regulations and inspections.