Nutrient cycles - Contamination L4 English in Natural Science 自然科学の英語 2006 自然科学の英語-ENS-L4 Ecosystem processes Respiration Metabolism [Consumers] Ingestion Respiration [Decomposers] Putrefaction Death [Primary production] Photosynthesis 2006 自然科学の英語-ENS-L4 Dead matter Carbon cycle CO2 Runoff Water CO3-2 Debris Dissolves CH2O soil Rocks CO3Ca•Mg 2006 Fossil fuels Metamorphism 自然科学の英語-ENS-L4 CO2 Combustion Respiration Terrestrial biota CH2O Dissolves Respiration Photosynthesis Atmosphere Photosynthesis Organic uptake Aquatic Biota CH2O Debris Sediments CO3Ca•Mg Nitrogen cycle microorganisms NOx Soil NH4 2006 Runoff Excretion Uptake N fixation Terrestrial biota N2O Combustion N fixation Storms NO3- N2O, NH3 Atmosphere Loss N2 Uptake Water Eutrophication Aquatic biota Debris Fertilizers 自然科学の英語-ENS-L4 Ocean sediments Phosphorous cycle Atmosphere Detergents Terrestrial biota Debris Excretion Uptake Fisheries Water Uptake Eutrophication Aquatic biota Debris Soil - rocks 2006 Fertilizers Metamorphism 自然科学の英語-ENS-L4 Ocean sediments Sulphur cycle SH2 Atmosphere Uptake 2006 Sea spray Volcanoes Excretion SO4-2 Soil - rocks Debris SO4-2 Water Uptake Aquatic biota Debris Metamorphism 自然科学の英語-ENS-L4 Ocean sediments Anaerobic respiration Terrestrial biota SH2 Combustion Acid rain Acid rain SO2 Primary productivity • Photosynthesis – Aquatic (algae) – Terrestrial (plants) 92.4 x 1012 kg/yr 132.1 x 1012 kg/yr 255 t/km2 yr 899 t/km2 yr C3: most plants Monocotyledons crop plants: wheat, rye-grass alfalfa, beans trees: Fagaceae, Pinus C4: tropics and arid zones tropical grasses Dicotyledons crop plants: corn, sugar cane sorghum, millet 2006 自然科学の英語-ENS-L4 Primary productivity (x109 tons C) Pole Biome Net PP Polar desert / alpine tundra 0.4 Wet tundra 0.6 Boreal woodland 1.1 Boreal forest 2.9 Temperate coniferous forest 1.1 Temperate mixed forest 3.3 Temperate deciduous forest / broadleaf evergreen 2.2 Temperate woodland 2.2 Mediterranean shrubland 0.5 Short grassland 1.0 Arid shrubland 1.8 Desert 0.6 Tall grassland 1.2 Tropical savannah 5.3 Dry tropical forest 2.9 Tropical deciduous forest 3.8 自然科学の英語-ENS-L4 Equator Tropical evergreen forest (jungle) 2006 18.0 Natural resources • Renewable Able to maintain yield – Biological • Forestry • Agriculture – Crops – Grazing animals Sustainable production • Fisheries • Non-renewable – Metals – Inorganic materials Recyclable • Fossil fuels (crude oil, coal) Non-recyclable 2006 自然科学の英語-ENS-L4 Biological resources x 1012 kg/ yr % total productivity Forest 48.7 36.9 Woodland 35.0 26.5 Grassland 17.1 12.9 Cultivated 15.0 11.4 Shrubland 7.7 5.8 Desert 3.1 2.3 Wetland 3.0 2.3 Tundra 2.1 1.6 Other 0.4 0.3 132.1 58.8 % Earth Freshwater 0.8 0.9 Oceans 91.6 99.1 AQUATIC 92.4 41.2 % Earth TOTAL EARTH 224.5 100 % Ecosystem TERRESTRIAL 2006 自然科学の英語-ENS-L4 Human use 45% 39 - 50% 8% Human use of natural resources 2006 (Vitousek et al., 1997) Freshwater usage >50% Nitrogen input (soil, water) Land transformation >50% CO2 input (atmosphere) Biodiversity loss >20% Fisheries 8% 自然科学の英語-ENS-L4 45% 20% A) Land transformation Objective: • Urban expansion population ~ 6 billion • Agriculture How? • Deforestation Tropical forest - Amazon, India, South-East Asia Temperate forest - USA, Europe, China Coastal mangroves (50%) • Annual rate ~1% – 2006 Exponential increase in the last 50 years 自然科学の英語-ENS-L4 Tropical deforestation • Cleared land unsuitable for agriculture – Rainfall loss of soil – topsoil lost decrease productivity • Big losses of biodiversity Deforestation (Km2/yr) Rate 1980-1990 (%) Area remaining in 1990 (Km2) Brazil 36,710 0.90 4,093,000 Venezuela 5,990 1.31 457,000 Bolivia 5,320 1.16 459,000 Colombia 3,670 0.68 541,000 Peru 2,710 0.40 674,000 Ecuador 2,380 1.98 120,000 2006 自然科学の英語-ENS-L4 Decrease absorption of atmospheric CO2 B1) Exploitation - fisheries Fishing industry 8% global productivity 35% continental shelf 3% discarded (non-target species: dolphin, etc) 22% overexploited (cod, sardine) 44% limit of exploitation (tuna) Colateral damage Dredging ocean floor Algal blooms • • 2006 自然科学の英語-ENS-L4 Fish kills Shellfish poisoning B2) Exploitation - forestry Resources – – – – – Timber, lumber Paper Rubber Fruits (nuts) Medicines Sustainability 1. Plantations 2. Adequate management • • 2006 Selective cutting NO clearcutting 自然科学の英語-ENS-L4 C) Impacts of climate change • Increased productivity (biomass) – 3.2 billion tons/yr CO2 C3 plants more biomass – Warmer atmosphere C4 plants advantage • Decreased yield in wheat, barley crops – Physiological threshold – Pollination failure fewer insects 2006 自然科学の英語-ENS-L4 X grain leaves D) Global biogeochemistry • Water – Humans use over 50% surface water • • • 70% used in agriculture (35% global) 6% evaporation losses 24% consumption - electricity – 2/3 of river flows regulated (dams, weirs) – Underground water NOT renewable - Saudi Arabia (3/4) • Ecosystem disturbances – Little water reaches the ocean: Colorado, Nile, Ganges • Estuary, coastal ecosystems fisheries losses – Inland seas dry up: Chad (Africa), Aral (Asia) • • • 2006 Biodiversity losses (fish, plants) Increase of dust, diseases Useless soil - salination 自然科学の英語-ENS-L4 Desertification …other impacts on aquatic ecosystems • Dams – erosion downstream – local climate (temperature, rainfall) • Change of chemistry – Danube river silica in Black Sea • Water pollution reduced water quality – Agrochemicals (fertilizers, pesticide residues) – Industry: chemical, mining, pharmaceutical, paper, plastics – Urban waste 2006 自然科学の英語-ENS-L4 Global biogeochemistry - Nitrogen • N Fixation (x 109 kg year) – Terrestrial ecosystems – Aquatic ecosystems – Human input 90-130 ~100 210 / yr • Fertilizers • Biofertilizers (legumes) • Fossil fuel combustion 140 40 20 200 / yr • Consequences – Increase in NO2 (greenhouse gas) and reactive N (NH4, NOx) in atmosphere – Acid rain (NO3-) damage to crops and forests – Water pollution: eutrophication algal blooms 2006 自然科学の英語-ENS-L4 • Sulphur – Fossil fuel combustion – Acid rain (SO4-) damage forest, crops, health • Phosphorous – Fertilizers – Water pollution: eutrophication algal blooms • Fuel combustion – smog (ozone) crop damage, health • Heavy metal mobilization - mining, industry – – – – – – 2006 Lead (Pb) Cadmium (Cd) Mercury (Hg) Nickel (Ni) Chromium (Cr) Copper (Cu) Very toxic 自然科学の英語-ENS-L4 Birth defects Alzheimer disease Minamata disease cancer 2006 自然科学の英語-ENS-L4 Effect of air pollutants on Picea forests (Schulze 1989) Chemicals in the environment • ‘All chemicals are toxic…it is only the dose which makes a thing a poison’ Paracelsus (1493-1541) – Toxic substance: negative effects at very low doses e.g. below ppm (mg/kg body weight) • Chemical industry in developed countries produces… 100 m tons/yr 70,000 different compounds 1,000 new every year 2006 自然科学の英語-ENS-L4 Chemical pollutants Source Main causes Pollutants Natural Volcanic eruptions Blue-green algal blooms Planktonic bloom SH2 Natural toxins Urban Sewage Solid waste treatment Household heating – fossil fuels NH3, P [not toxic] Dioxins CO2, polycyclic aromatic hydrocarbons (PAH) Industry Chemical & pharmaceutical waste Anilines, phenols, plasticisers Mining waste/spills Cyanides, heavy metals (Pb, Hg, Cu) Electrical insulators Polychlorinated biphenyls (PCB) Transport Combustion gases Oil (petroleum) spills CO, CO2, SO2 Aromatic hydrocarbons (AH, etc) Agriculture Fertilizers Pesticides N2O, NO3-, PO4-2 [not toxic] As, organic toxins 2006 自然科学の英語-ENS-L4 Environmental pollution Waste disposal Air Industry Chemical Mining Biota Water Energy fuels Soil Agrochemicals 2006 自然科学の英語-ENS-L4 Long-range transport Global distillation effect Very volatile compounds condense with latitude Example: ocean waters (40-60 m deep) – HCH: hexachlorocyclohexane – CHBs: chlorobornanes (toxaphene) – HEPX: heptachlor exoepoxide – TC, CC: trans-, cischlordane – Endo-I and II: endosulfan – TN: trans-, cis-nonachlor 2006 自然科学の英語-ENS-L4 (Jantunen and Bidleman, 1998) Bioamplification • Multiplication effect through the ecosystems’ food web • Due to cumulative nature of some chemicals: – Persistent, resistant to degradation – Heavy metals, Organochlorines (PCBs, DDT, etc), Dioxins 2006 自然科学の英語-ENS-L4 Aquatic bioindicators • Mollusks: mussels, clams, oysters – – – – Ecology: filter water and particles Sedentary, easy to collect, long life Tolerant to neurotoxic insecticides Accumulation of OC and OP residues • Crustaceans: – Waterflea Daphnia magna • Bioassay for ChE inhibiting insecticides (OP, Carb) – Shrimp Thamnocephalus spp. • Bioassay for micotoxins and CYN • Birds: dipper (Cinclus spp.) – Ecology: pristine streams in mountains feed on aquatic larvae – Indirect indicators of pollution - food disappearance 2006 自然科学の英語-ENS-L4 • Industry Solutions to pollution Reduce outputs: filter traps recycle or destroy waste (remediation) • Agrochemicals Reduce inputs: fertilizers + pesticides • New methods of pest control Bioremediation of residues • Waste Reduce input = less consumption Improve disposal • Incinerators (burning) and compost technology • Energy - fossil fuels are NOT sustainable 2006 自然科学の英語-ENS-L4 clean energy sources - solar, wind, geothermal References • Lange et al. (eds). 1983. Ecosystem processes : mineral cycling, productivity and man's influence / 松戸閲覧室 call 471.5||E • Freedman, W. 1989. Environmental ecology: the impacts of pollution and other stresses on ecosystem structure and function / 園芸緑地植物学 call 466 • Vitousek et al. 1997. Human domination of Earth’s ecosystems. Science 277: 494-499 2006 自然科学の英語-ENS-L4
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