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Bahan kajian pada MK. Pertanian Berlanjut. EFEK PERTANIAN TERHADAP LINGKUNGAN. Diabstraksikan oleh : smno.jurstnh.fpub.sept2012. Bagaimana Pertanian mengubah Lingkungan.
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Bahankajianpada MK. PertanianBerlanjut EFEK PERTANIAN TERHADAP LINGKUNGAN Diabstraksikanoleh: smno.jurstnh.fpub.sept2012
BagaimanaPertanianmengubahLingkungan • Pertanianmerupakanaktivitas yang snagatpentingbagikehidupanmanusia, danmenjadisalahsatusumberkerusakanlingkungan • Problematiklingkungan yang serius: • Soil erosion • Sediment transport and deposition downstream • On-site pollution from overuse and secondary effects of fertilizers and pesticides • Off-site pollution of other ecosystems, of soil, water and air
BagaimanaPertanianmengubahLingkungan Problematiklingkungan yang serius: • Deforestation • Desertification • Degradation of aquifers • Salinization • Akumulasisenyawaorganiktoksik • Kehilanganbiodiversitas
BAHAYANYA PERTANIAN Industrial Key: AWL to Study, Low-frequency Vocabulary What are the hazards of industrial agriculture?
PERTANIAN ORGANIK: SEDANG BERKEMBANG • Consumer demand for organic farming is rising at 20% per year. • The highest growth is in Argentina, US, and China. • People are growing consciousof adverse effects of industrial agriculture, where there is a focus on maximizing profits at the expense of health and the environment. Bagaimanapemikiranandabahwapertanian-industrial berkontribusipadapemanasan global danpencemaran air?
RISIKO KESEHATAN : METODE Industrial • Pesticide residues on produce • remain after washing and peeling. • have links to cancer. • Antibiotics we ingest • from plant and animal sources • lead to the development of untreatable superbugs Apakahandakhawatirtentangadanyaresidupestisidaatauantibiotikdidalambahanpanganprodukpertanian ?.
RISIKO KESEHATAN • Plant and animal growth hormones • disruptendocrinesystem. • lead to early puberty. • Biological engineering • Unregulated items are virtually invisible in stores. • Manipulation of genetic code could impact health. How do you think genetically modified food might impact your health?
BAHAYA LINGKUNGAN • Environmental hazards comprise air pollution, global warming, and other problems. • Synthetic fertilizers • largest source of nitrous oxide emissions • 300 times more toxic than carbon dioxide gases • will affect air pollution and intensify global warming if continued Are you concerned about air pollution in your country? Why or why not?
TANAH YANG TIDAK LESTARI • Industrial mono-cropping: one crop is planted repeatedly on a single field. • The process relies on the use of synthetic fertilizers. • Mono-cropping kills microorganisms needed to produce soil nutrients. • Infertile soil leads to erosion, unsustainable farmlands, and reduced biodiversity. If mono-cropping is destroying farmlands and biodiversity, what is the alternative?
PERTANIAN ORGANIK • Organic farming prohibits the use of synthetic fertilizers and pesticides, hormones, antibiotics, and genetically modified organisms. • It ensures soil sustainability and overall quality. What are the advantages of eating organic food?
ROTASI TANAMAN • Holisticfarming techniques • infusesoil with essential nutrients. • ensure different crops are planted every year. • vary the nutrient demand in soil. • create sustainable soil.
KESEJAHTERAAN TERNAK • Small-scale organic farms are • less likely to confine livestock to small spaces. • against the use of antibiotics. • Free-range farms • allow animals to roam freely. • reduce stress and susceptibility to disease. How do you feel about confining animals to small spaces in order to produce food?
The Plow Puzzle • Nothing in nature like the plow • Big difference between soils of an unplowed forest and soils of previously forested land that has been plowed and used for ag • Soil difference noted in Marsh’s book • Man and Nature in 1864 Diunduhdarisumbernya: ………… 20/10/2012
The Plow Puzzle Semakinkritiskondisitanah, semakinbanyak input produksi yang diperlukan, sepertipupuk, pestisida, air irigasidanlainnya. Diunduhdarisumbernya: http://www.ipm.iastate.edu/ipm/icm/2001/1-29-2001/soilerosion.html………… 22/10/2012
TANAH YANG TEREROSI = LAHAN KRITIS • When land cleared of its natural vegetation, the soil begins to lose its fertility • Physical erosion • Became a global issue in the world • Intense plowing + drought • Loosened soil blow away Diunduhdarisumbernya: ………… 20/10/2012
TANAH YANG TEREROSI = LAHAN KRITIS • The land that became the Dust Bowl had been prairie • Deep rooted grasses that held soil in place • After plowing soil exposed to elements • When original vegetation is cleared soil changes • Crops harvested and removed, less organic matter returning to soil • Soil exposed to sunlight which speeds rate of decomposition Diunduhdarisumbernya: ………… 20/10/2012
TANAH YANG TEREROSI = LAHAN KRITIS • Traditionally decline in soil fertility combated using organic fertilizers • Animal manure • In the 20th century crop production increased • Chemical or artificial fertilizers • Add nitrogen and phosphorous to the soil Diunduhdarisumbernya: ………… 20/10/2012
TANAH YANG TEREROSI = LAHAN KRITIS Lahankritistelahmengalamikerusakanbaiksecarafisika, kimia, maupunbiologi. Jumlahlahankritisdi Indonesia semakinmeningkatseiringadanyapembukaandanpenggundulanhutan, penambangan, sertaeksploitasi yang berlebihanterhadaptanah. Diperkirakansaatiniluaslahankritismencapai 77,8 jutahektare, yang terdiridarilahanagakkritismencapai 47,6 jutahektar, lahankritisseluas 23,3 jutahektar, danlahansangatkritismencapai 6,8 jutahektar. Diunduhdarisumbernya: http://gerbangtani.wordpress.com/2012/08/18/perbaikan-lahan-kritis/ ………… 22/10/2012
Kemana material tanah yang tererosi • A lot of it travels down streams and rivers • Deposited at their mouths • Fill in water ways • Damage fisheries and coral reefs • Sedimentation has chemical effects • Enrichment of waters, eutrophication • Transport of toxic chemical pesticides Diunduhdarisumbernya: ………… 20/10/2012
Bagaimanamelestarikantanah • Soil forms continuously • But very slowly • 1mm of soil formation takes 10-40 years • To be truly sustainable soil lost should equal amount of new soil produced Diunduhdarisumbernya: ………… 20/10/2012
Pengolahantanahmenurutkontur • Land is plowed perpendicular to the slopes and as horizontally as possible. • One of the most effective ways to reduce soil erosion • Also uses less fuel and time Diunduhdarisumbernya: ………… 20/10/2012
PertanianTanpaOlah Tanah (TOT) • Involves not plowing the land, using herbicides and integrated pest management to keep down weeds, and allowing some weeds to grow. • The goal is to suppress and control weeds but not eliminate them at the expense of soil conservation • Additional benefit reduces the release of CO2 Diunduhdarisumbernya: ………… 20/10/2012
Pengendalian Hama • Pests are undesirable • Competitors, parasites, and predators • In agriculture pests are mainly • Insects, nematodes, bacterial and viral diseases, weeds and vertebrates. • Loss can be large • Estimated at 1/3 of potential harvest and 1/10 of the harvested crop Diunduhdarisumbernya: ………… 20/10/2012
Pengendalian Hama • Because a farm is maintained in a very early stage of ecological succession and enriched by fertilizers and water • It is a good place for crops • AND early-successional plants (weeds) • Weeds compete for all resources • Light, water,nutrients, and space to grow. Diunduhdarisumbernya: ………… 20/10/2012
SejarahPestisida • Pre- Industrial Revolution methods • Slash and burn agriculture • Planting aromatic herbs that repel insects • Modern science-based agriculture • Search for chemicals that would reduce abundance of pests • The first, like arsenic, toxic to all life • Killed pest and beneficial organisms Diunduhdarisumbernya: ………… 20/10/2012
Sejarah Pestisida • Second stage began in the 1930 • Petroleum based sprays and natural plant chemicals (e.g., nicotine) • Third stage was the development of artificial organic compounds • DDT, broad-spectrum • Aldrin and dieldrin used to control termites • Toxic to humans, has been found in breast milk Diunduhdarisumbernya: ………… 20/10/2012
Sejarah Pestisida • Forth stage is a return to biological and ecological knowledge. • Biological control- the use of biological predators and parasites to control pests • The use of Bacillusthuringiensis(BT) • Proved safe and effective Diunduhdarisumbernya: ………… 20/10/2012
Sejarah Pestisida • Other biological control agents • Small wasps that parasitize caterpillars • Both effective and narrow spectrum • Ladybugs • Sex pheromones (chemicals released to attract opposite sex) used as bait in traps Diunduhdarisumbernya: ………… 20/10/2012
Integrated Pest Management (Pengelolaan Hama Terpadu) • Fifth stage • IPM uses a combination of methods • Biological control • Chemical pesticides • Methods of planting crops (mixed fields) • Goal can be control not elimination of pest • Economically makes sense • Does less damage to ecosystem, soil, water and air Diunduhdarisumbernya: ………… 20/10/2012
Integrated Pest Management (Pengelolaan Hama Terpadu) • No-till or low-till agriculture another feature of IPM • Helps build levels of natural enemies of pests Diunduhdarisumbernya: ………… 20/10/2012
Monitoring PesticidadiLingkungan • World pesticide use exceeds 2.5 billion kg • US use exceeds 680 million kg • $32 billion worldwide, $11 billion in US • Once applied may decompose in place or be carried by wind and water • Breakdown products can also be toxic • Eventually fully decompose but can take a very long time Diunduhdarisumbernya: ………… 20/10/2012
Integrated Pest Management (Pengelolaan Hama Terpadu) • To establish useful standards for pesticide levels in the environment and to understand the environmental effects, it is necessary to monitor the concentrations. • Standards have been set for some but not all compounds Diunduhdarisumbernya: ………… 20/10/2012
Genetically Modified Crops(Tanamanrekayasagenetik) • Three methods • 1. Faster and more efficient development of new hybrids • 2. Introduction of the “terminator gene” • 3. Transfer of genetic properties from widely divergent kinds of life Diunduhdarisumbernya: ………… 20/10/2012
HibridaBaru • From an environmental perspective, genetic engineering to develop hybrids w/in a species is likely to be a benign as the development of agricultural hybrids has been w/ conventional methods. • Concern that genetic modification may produce • “superhybrids” • Could become pest or transfer genes to closely related weeds Diunduhdarisumbernya: ………… 20/10/2012
The Terminator Gene • Makes seeds from a crop sterile • Done for environmental and economic reasons • Prevents a gmo from spreading • Protects the market for the corporation that developed it • Critics note • Farmer’s in poor nations must be able to grow next years crops from their own seeds Diunduhdarisumbernya: ………… 20/10/2012
TRANSFER GEN • Genes transfer from one major life form to another • Most likely to have negative and undesirable impacts • E.g. Bacillusthuringiensis • Produce toxin that kills caterpillars • Gene identified and transferred to corn • Engineered corn now produces its own pesticide Diunduhdarisumbernya: ………… 20/10/2012
TRANSFER GEN • Bt plants thought to be a constructive step in pest control • No longer need to spray pesticide • Bt plants produce toxin in all cells • Even in pollen that can spread • Monarch butterflies that eat pollen may die Diunduhdarisumbernya: ………… 20/10/2012
Grazing on Rangelands • Almost half of the Earth's land area is used as rangeland • 30% of Earth’s land area is arid rangeland • Arid rangeland easily damaged especially in time of drought • Steams and rivers also damaged • Trampling banks and fecal matter Diunduhdarisumbernya: ………… 20/10/2012
Traditional and Industrial Use of Grazing and Rangelands • In modern industrialized agriculture • Cattle initially raised on open range • Then transport to feed lots • Major impact is local pollution from manure • Traditional herding practices • Damage land through overgrazing • Impact varies depending on density relative to rainfall and soil fertility Diunduhdarisumbernya: ………… 20/10/2012
BiogeografiTernak-Pertanian • Everyplace people have dispersed they have bought animals w/ them • Pre-industrial and throughout western civilization • Environmental effects of introductions • Native vegetation may be greatly reduced and threatened w/ extinction • Introduced animals may compete w/ native herbivores, threatening them w/ extinction as well Diunduhdarisumbernya: ………… 20/10/2012
DAYA DUKUNG LAHAN GEMBALAAN • Carrying capacity- • the maximum number of species per unit area that can persist w/o decreasing the ability of that population or its ecosystem to maintain that density in the future. • When the carrying capacity is exceeded, the land is overgrazed. Diunduhdarisumbernya: ………… 20/10/2012
DAYA DUKUNG LAHAN GEMBALAAN • Overgrazing • Slows the growth of vegetation • Reduces the diversity of plant species • Leads to dominance by plant species that are relatively undesirable to the cattle • Hastens loss of soil by erosion • Subject the land to further damage from trampling Diunduhdarisumbernya: ………… 20/10/2012
PERKEMBANGAN DESERT (GURUN) • Deserts occur naturally where there is too little water for substantial plant growth. • The warmer the climate the greater the rainfall needed to convert an area from desert to non-desert • The crucial factor is available water in the soil for plant use • Factors that destroy the ability of a soil to store water can create a desert Diunduhdarisumbernya: ………… 20/10/2012
PERKEMBANGAN DESERT (GURUN) • Earth has five natural warm desert regions • Primarily between 15o and 30o north and south of the equator • Based on climate 1/3 of Earth’s land area should be desert • 43% of land is desert • Addition area due to human activities Diunduhdarisumbernya: ………… 20/10/2012
PERKEMBANGAN DESERT (GURUN) • Desertification – the deterioration of land in arid, semiarid, and dry sub humid areas due to changes in climate and human activities. • Serious problem that affects 1/6 of world population (1 billion people) Diunduhdarisumbernya: ………… 20/10/2012
APA YANG MENYEBABKAN DESERTS • The leading cause of desertification are bad farming practices. • Failure to use contour plowing • To much farming • Overgrazing • Conversion of rangelands to croplands in marginal areas • Poor forestry practices Diunduhdarisumbernya: ………… 20/10/2012
APA YANG MENYEBABKAN DESERTS • Desert like areas can be created anywhere by poisoning of the soil • World wide chemicals account for 12% of soil degradation • Irrigation in arid lands can cause salts to build up to toxic levels Diunduhdarisumbernya: ………… 20/10/2012