Material Flow Carol Timson 4/12/2004

Overview l Biogeochemical Systems Mass Balance l Ecosystem Closed Loop l Anthroposystem Open System l Material Flow Transfer Matrices Track flow of contaminants throughout the World l 4 Environmental Spheres - all spheres are interdependent Biosphere-pump Atmosphere-transporter Lithosphere-storage compartment Hydrosphere-transporter (rivers) & storage (oceans)

Biogeochemical Systems l The study of how living systems influence, and are controlled by, the geology and chemistry of the earth Fundamental principles to analyze flow of materials through air, land, and water l Mass balance - describes the state of a system NET CHANGE = INPUT + OUTPUT + INTERNAL CHANGE Internal Change m in m out

Ecosystem The sun is the energy source Plants use the sun to produce food Animals are the consumers The decomposers (recyclers) are the fungi and bacteria. The ecosystem is capable of recycling most of the waste products is produces.

Antroposystem Open Loop System Fossil Fuels are the energy for the system Producers include manufacturing and farming Consumers are humans Decomposing (recycling) is very minor Includes recycling of material and wastewater treatment by-products are disposed into the physical environment

Material Flow l Humans and biota are responsible for redistribution of chemicals on Earth. l In an ecosystem much of the material is transferred directly from the producers to the recyclers l This is not the case in the anthroposystem as it would be pointless to produce material and immediately recycle it.

Material Flow Transfer Matrices l Matter is transferred from producer to consumer. l The transfer is a one-to-many relationship that can be quantified by the transfer matrix. l In case of fuel producers (mining) and consumers (combustion), the transfer is described by the surface transfer matrix s ij l Pollution is transferred from the consumer (emitter) to the environmental receptor (pollutant is emitted) i = producer j = consumer k = receptor

Matrix Example Expand this example, start with P, ci Work it through the receptor Rk M i -mass contaminant that is mobilized by each producer c i -concentration of the contaminant sulfur in coal P i -raw material production rate s ij -transfer of coal sulfur from producer to consumer U ij -amount of matter originating at the producer and used at the consumer. M i =c i P i U ij =s ij M i

Four Environmental Spheres Intro: materials in the environment are distributed in four env compartments materials flow between the compartments environmental problems arise when….??? l Biosphere The pump, allows matter to flow through nature thin shell of organic matter on the earth’s surface l Atmosphere Transport-conveyor compartment Large capability for redistributing matter l Lithosphere solid shell of inorganic material at the earth’s surface l Hydrosphere can be seen as two compartments: rivers are transporters and oceans are storage

Mercury traveling through the Spheres Released by anthropogenic sources into land air soil Mercury in Atmosphere mixes with cloud water and is deposited on the land and in water sources On land it is stored in the soil and also deposited into water sources from runoff Mercury is re-emitted into the atmosphere from the ocean through evasion

Mercury l Mercury in the soil is also taken up by plants and these plants are consumed by animals. l Mercury in water in ingested by water animals also. l (sequence) Mercury can get into freshwater systems through direct deposition, runoff, or through groundwater flow in the upper soil layers l Reference?? l Relate your Mercury story to the four spheres

Mercury Transport l Approximately one third of total mercury emissions are thought to cycle from oceans to the atmosphere and back again to the ocean. l The reservoir holding time is approximately 6 months to 2 years l Hg(0) emitted transforms to Hg(II) in cloud water. Hg(0) has an average residence time in the atmosphere of about 1 year. l Hg(II) is deposited by dry or wet deposition process. Atmospheric residence time of hours to months

Conclusion l Ecosystem makes use of all material l The anthroposystem differs from the ecosystem in the fact that they do not recycle as much l Sustainable development can be achieved if humans can operate more like the ecosystem by becoming more efficient. Either use less material or recycle more anything else ??? Place it where it is harmless??