Presentation on theme: "Agriculture. Arable Land There is a decline in the amount of arable land."— Presentation transcript:
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.