Loss of crop diversity commercial wants food to look pretty Seed banks are

Loss of crop diversity commercial wants food to look

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Loss of crop diversity -> commercial wants food to look pretty Seed banks are living museaus for seeds Seed banks and genre banks - > genetic diversity Raising animals for food Don’t need to eat that much meat 20% livestock classified as a risk High demand -> feedlots - concentrated animals o Greater production of food o + helps not take over landscape o Waste = pollutant Antibiotics can come through food chain, unclean places Raising fish on 'farms' o Aquaculture -> open water floating net pens, tanks o + Reduce fishing Employment Less fossil fuel Energy efficient o - Inc pressure on wild fish Inc proportion fish Dense conc = inc disease, reduce food sec, antibiotics Competition GM Sustainable agriculture Does not deplete soil faster then form Low input agriculture Composting = organic agriculture other crops are grown in plots using different treatments:
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- conventional farming using chemical pesticides, herbicides, and inorganic fertilizers - conventional farming that also uses organic fertilizer (cattle manure) - organic farming using only manure, mechanical weeding, and plant extracts to control pests - organic farming that also adds natural boosts, such as herbal extracts in compost - Local agriculture Food production grown faster than pop Most genetically modified crop = soybeans Crops important for food security -> variety help pesticide resistance
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Chapter 9 conservation of species and habitats Biodiversity can be applied at all levels (diversity of species, genes, pop, community, ecosystems) Permian period - worst extinction 90% Ecosystem services = benefits to humans free of charge Parks and protected areas = conserving biodiversity preserves whole natural systems and species Our planet of life Some groups hold more species than others Scientific name -> genus and species Subspecies -> diff geological areas Biodiversity encompasses several levels Genetic diversity Subspecies -> genetic differences Genetic diversity = varieties in DNA among individuals within species, subspecies and populations More genetic diversity = better enable to cope with enviro changes Depressed genetic diversity -> inbreeding depression = genetically similar parents produce defective offspring Dramatic decrease in pop can cause a genetic bottleneck o Limited variety or genetic material passed down o Northern elephant seal Species diversity Species richness, evenness, relative abundance Expiration -> local extinction of species o Siberian tiger Speciation, extinction, immigration, emigration Ecosystem and habitat diversity Number of ecosystems based on variations in climate Community types and habitat availability Human disturbances dec diversity Biodiversity is unevenly distributed on the planet Species richness generally is as one approaches the equator = latitude gradient o Plant productivity and climate Screen clipping taken: 2018-11-30 8:43 PM Aseasonality assures that a single species will not dominate Polar and temperate regions lack species o Glaciation forces animals out
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