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Developed countries include the
United States, Canada, Japan, Australia, New Zealand and most European countries. Most are highly industrialized and have high average per capita GDP. Have lower population, lower population growth, high amount of wealth and income, higher amount of resource use and high amount of pollution and waste.
Developing Countries most of them in
Africa, Asia, and Latin America. Some are middle-income, moderately developed countries.
Developing Countries Have a higher
population, high population growth, lower income and wealth, lower resource use and lower pollution and waste.
replenished fairly rapidly through natural processes as long as it is not used up faster than it is replaced. Examples include forests, grasslands, wild animals, fresh water, fresh air and fertile soil.
Nonrenewable Resource: can be economically depleted
to the point where it costs too much to obtain what is left. Some can also be recycled and reused.
Nonrenewable Resource exist
fixed quantity or stock in the earth's crust. Energy resources (coal, oil, and natural gas), metallic mineral resources (iron, copper, aluminum) and nonmetallic mineral resources (salt, clay, sand and phosphates).
it is when the costs of extracting and using what is left exceed its economic value.
involves collecting waste materials, processing them into new materials, and selling these new products.
is the presence of chemicals at high enough levels in air, water, soil or food to threaten the health, survival, or activities of humans or other living organisms.
a thin covering over most land that is a complex mixture of eroded rock, mineral nutrients, decaying organic matter, water, air, and billions of living organisms, most of them microscopic decomposers.
when bedrock is broken down into fragments and particles of physical, chemical and biological processes (weathering). Soil helps control the earth's climate by removing carbon dioxide from the atmosphere and storing it as carbon compounds.
, or soils that have developed over a long period of time, are arranged in a series of horizontal layers called Soil Horizons, each with a distinct texture and composition that varies with different types of soils. Most mature soils have at least three of the possible horizons.
or the surface little layer: contains freshly fallen undecomposed or partially decomposed leaves, twigs, crop wastes, animal waste, fungi, and other organic material. Normally it is brown or black.
or topsoil layer: is a porous mixture of the partially decomposed bodies of dead plants and animals called humus, and inorganic materials such as clay, silt, and sand. A fertile soil that produces high crop yields has a think topsoil layer, with lots of humus, which helps hold water and nutrients taken up by plant roots. The roots of most plants and the majority of a soil's organic matter are concentrated in a soil's two upper layers. The two top layers are also the most well developed soils teem with bacteria, fungi, earthworms, and small insects that interact in complex food webs.
parent material: contain most of a soils inorganic matter, mostly broken-down rock consisting of varying mixtures of sand, silt, clay, and gravel much of it transported by water from the A horizon.
Gray, bright yellow, and red topsoil
are low in organic matter and need nitrogen enrichment to support most crops.
water seeps down, it dissolves various minerals and organic matter in upper layers and carries them to lower layers.
physical and chemical processes in which solid rock exposed at the surface is changed to separate solid particles and dissolved material, which can them be moved to another place as sediment.
is the atmosphere's most abundant element making up 78% of the volume in the troposphere.
Nitrogen in the N cycle
cannot be absorbed and used directly as nutrient by multicellular plants of animals.
types of bacteria called nitrogen-fixing bacteria in aquatic systems, in the soil, and in the roots of some plants complete this conversion of Nitrogen to usable NO2 NO3.
(hot, dry climate): mosaic of closely packed pebbles, boulders. Weak humus-mineral mixture. Dry, brown to reddish-brown with variable accumulations of clay, calcium carbonate, and soluble salts.
Deciduous Forest Soil
forest little leaf mold, humus-mineral mixture. Light, grayish-brown, silt loam. Dark brown firm clay.
Coniferous Forest Soil
acid litter and humus. Light-colored and acidic. Humus and iron and aluminum compounds.
cyclic movement of carbon in different chemical forms from the environment to organisms and then back to the environment. If the carbon cycle removes too much carbon dioxide from the atmosphere, the atmosphere will cool; if it generates too much carbon dioxide the atmosphere will get warmer. Terrestrial producers remove carbon dioxide from the atmosphere, and aquatic producers remove it from the water. They then use photosynthesis to convert carbon dioxide into complex carbohydrates such as glucose. The linkage between photosynthesis in producers and aerobic respiration in producers, consumers and decomposers circulates carbon in the biosphere. Oceans play important roles in the carbon cycle. Oceans can dissolve carbon dioxide. Human effects: burning fossil fuels and clearing photosynthesizing vegetation faster than it is replaced can increase the earth's average temperature by adding excess carbon dioxide to the atmosphere.
specialized bacteria in soil and aquatic environments convert gaseous nitrogen to ammonia that is converted to ammonium ions that can be used by plants.
not taken up by plants may undergo nitrification (a two-step process). Specialized soil bacteria convert most of the ammonia and ammonium ions in soil first to nitrite ions, which are toxic to plants and then nitrate ions, which are easily taken up by the roots of plants.
vast armies of specialized decomposer bacteria convert this organic material into simpler nitrogen=containing inorganic compounds such as ammonia and water-soluble salts containing ammonium ions.
nitrogen leaves the soil as specialized bacteria in waterlogged soil and in the bottom sediments of lakes, oceans, swamp, and bogs convert ammonia and ammonium ions back into nitrite and nitrate ions, and then into nitrogen gas and nitrous oxide gas.
cyclic movement of sulfur in various chemical forms from the environment to organisms and then back to the environment. Most of the earth's sulfur is stored underground in rocks and mineral and buried deep under ocean sediments. Sulfur can also enter the atmosphere from several natural resources: hydrogen sulfide and sulfur dioxide. Particles of sulfate salts, such as ammonium sulfate enter the atmosphere from sea spray, dust storms and forest fires. Human effects: burning coal and oil, refining oil, and producing some metal from ores add sulfur dioxide to the atmosphere.
cyclic movement of phosphorus in different chemical forms from the environment to organisms and the back to the environment. It circulates through water, the earth's crust and living organisms. Very little phosphorus circulates in the atmosphere because soil conditions do not allow bacteria to convert chemical forms of phosphorus to gaseous forms of phosphates. Phosphorus typically is found as phosphate salts containing phosphate ions in terrestrial rock formations and ocean bottom sediments. Plants obtain phosphorus as phosphate ions directly from soil or water and incorporate it in various organic compounds. Animals get their phosphorus from plants and eliminate excess phosphorus in their urine. Human effects: we remove large amounts of phosphate from the earth to make fertilizer, reduce phosphorus in tropical soils by clearing forests, and add excess phosphates to aquatic systems.
evolution in which two or more species interact and exert selective pressures on each other that can lead each species to undergo adaptations.
have broad niches. They can live in many different places, eat a variety of foods, and tolerate a wide range of environmental conditions.
occupy narrow niches. They may be able to live in only one type of habitat, use one or a few types of food, or tolerate a narrow range of climatic and other environmental conditions. This makes specialist more prone to extinction when environmental conditions change.
total way of life or role of a species in an ecosystem. IT includes all physical, chemicals, and biological conditions that specie needs to live and reproduce in an ecosystem. It is important that each species has a distinct niche or role to play in the ecosystem where it is found.
: full potential range of the physical, chemical and biological factors as species can use it does not face any competition from other species.
natural effect that releases heat in the atmosphere (troposphere) near the earth's surface. Water vapor, carbon dioxide, ozone and other gases in the lower atmosphere (troposphere) absorb some of the infrared radiation (heat) radiated by the earth's surface. Their molecules vibrate and transform the absorbed energy into longer-wavelength infrared radiation in the troposphere. If the atmospheric concentrations of these greenhouse gases increase and other natural processes do not remove them, the average temperature of the lower atmosphere will increase gradually. .
: heated air masses rising above the equator and moving north and south to cooler areas are deflected to the west or east over different parts of the planet's surface. The direction of air movement in the resulting huge atmospheric regions called cells sets up belts of prevailing winds-major surface winds the blow almost continuously and distribute air, moisture, and dust over the earth's surface.
influence climate by distributing heat from place to place making and distributing nutrients.
Global air circulation
is affected by the uneven heating of the earth's surface by solar energy, seasonal changes in temperature and precipitation, rotation of the earth on its axis, and the properties of air, water, and land.
is tilted with respect to the sun's rays. As a result, regions away from the equator are tipped toward or away from the sun most of the year, as the earth makes its annual revolution around the sun. This created opposite seasons in the northern and southern hemispheres.
Phytoplankton or plant plankton
which includes many types of algae. They and various rooted plants near shorelines are producers the support most aquatic food chains and webs.
consist of primary consumers that feed on phytoplankton and secondary consumers that feed on other zooplankton.
much smaller plankton, photosynthetic bacteria may be responsible for 70% of the primary productivity near the ocean surface.
are bottom dwellers such as barnacles and oysters that anchor themselves to one spot, worms that burrow into the sand or mud, and lobsters and crabs that walk about on the bottom.
that break down the organic compounds in the dead bodies and wastes of aquatic organisms into simple nutrient compound for use by aquatic producers.
is the warm, nutrient-rich, shallow water that extends from the high-tide mark on land to the gently sloping, shallow edge. This zone had numerous interactions with the land and human activities. Makes up less then 10% of the ocean but contains 90% of all marine species. Has a high net primary productivity per unit of area thanks to the zone's ample supplies of sunlight.
is the brightly lit upper zone where floating and drifting phytoplankton carry out photosynthesis. Nutrient levels are low and levels of dissolved oxygen are high. Large, fast-swimming predatory fish such as swordfish, sharks and bluefin tune populate this zone.
is dimly lit middle zone that does not contain photosynthesizing producers because of a lack of sunlight. Zooplankton and smaller fish, many of which migrate to feed on the surface at night, populate this zone.
is dark and very cold and has little dissolved oxygen. Nevertheless, the ocean floor contains enough nutrients to support a large number of species.
: is where the river meets the sea. Partially enclosed bodies of water, seawater mix with freshwater as well with nutrients and pollutants from rivers, streams, and runoff from land. Some of the world's most productive ecosystems because of high nutrient inputs from rivers and nearby land, rapid circulation of nutrients by tidal flows, presence of many producer plants, and ample sunlight penetrating the shallow waters.
is an area of shoreline between low and high tides. Organisms living in this zone must avoid being swept away or crushed by waves, the deal with being immersed during high tides and left high and dry at low tides. They also must be able to survive changing levels of salinity when heavy rains dilute saltwater. Organisms experiencing daily low and high tides have evolved a number of ways to survive under harsh and changing conditions.
: a mouth of a river, which is divided into many channels as it flows it, builds up by deposited sediment. Deltas absorb and slow the velocity of floodwaters from storms, tropical cyclones and tsunamis.
lake with a large or excessive supply of plant nutrients, mostly nitrates and phosphates. Lakes typically are shallow and have murky brown or green water with poor visibility, Because of their high levels of nutrients; there lakes have a high net primary productivity.
lake with a low supply of plant nutrients. This type of lake is often deep and has steep banks.
are lands covered with freshwater all or part of the time and located away from coastal areas. They include marshes, swamps, and prairie potholes (small shallow ponds in depressions carved out by ancient glaciers), floodplains and arctic tundra.
remain under water or soggy for only a short time each year. Dams, cities, farmlands, and filled-in wetlands alter and degrade freshwater habitats. Since the 1600's, over half of the wetlands in the United State have been drained and converted to other uses, mostly for growing crops.
the number of different species it contains (species richness) combined with the abundance of individuals within each of those species.
other species that migrates into or is deliberately or accidentally introduced into a community.
which play a major role in shaping communities by creating and enhancing their habitats in ways that benefit other species.
: species with a broad ecological niche. They can live in many different places, eat a variety of foods, and tolerate a wide range of environmental conditions.
species with a narrow ecological niche. They may be able to live in only one type of habitat, tolerate only a narrow range of climatic and other environmental conditions, or use only one type or a few types of food.
: two species or a network of species interact in a way that benefits both. Example clownfish and sea anemone.
: in an interaction that benefits one species but has little, if any, effect on the other species. Example birds can benefit from trees by making their nests in them.
: occurs when one species (the parasite) feeds on part of another organisms (the host), usually by living on or in the host. In this relationship, the parasite benefits and the host are harmed.
attempts by members of two or more species to use the same limited resources in an ecosystem.
attempts by two or more organisms of a single species to use the same limited resources in an ecosystem.
: involves the gradual establishment of various biotic communities in lifeless areas where there is no soil in a terrestrial community or no bottom sediment in an aquatic community.
in which a series of communities with different species develop in places containing soil or bottom sediment.
starts slowly but then accelerates as the population increases because the base size of the population is increasing.
a plot of the number of individuals against time, also known as a logistic growth: involves rapid exponential population growth followed by a steady decrease in population growth with time until the population size levels off.
many small offspring, little or no parental care and protection of offspring, early reproductive age, small adults, high population growth rate, generalist niche.
fewer, larger offspring, high parental care and protection of offspring, later reproductive age, and most offspring survive to reproductive age, large adults, lower population growth rate, and specialist niche.
Old growth forest
an uncut or regenerated forest that has not been seriously disturbed by human activities or natural disasters for at least several hundred years. They are storehouse of biodiversity because they provide ecological niches for a multitude of wildlife species.
a stand of trees resulting from natural secondary ecological succession. These forests develop after the trees in an area have been removed by human activities or by natural forces.
Tree plantation or tree farm
it is a managed tract with uniformly aged trees of one or two genetically uniform species that are harvested by clear-cutting as soon as they become commercially valuable.
intermediate-aged or mature trees in an uneven-aged forest are cut singly or in small groups. It reduces crowding, removes diseased trees, encourages growth of younger trees, maintains a stand of trees of different species and ages, and allows a forest to be used for multiple purposes.
some tree species that grow best in full or moderate sunlight are all removed in a single cut. It produces higher timber yields, needs less skill and planning. However, it reduces biodiversity, disrupts ecosystem processes, destroys and fragments wildlife habitats.
a clear-cutting variation that can allow a more sustainable timber yield without widespread destruction. It involves clear-cutting a strip of trees along the contour of the land, with the corridor narrow enough to allow natural regeneration within a few years.
controlled surface fires
Reduce fire damage, we can set controlled surface fires, allow fires on most public lands to burn unless they threaten human structures and lives, and clear small areas around buildings in areas subject to fire.
Have so few individual survivors that the species could soon become extinct over all or most of its natural range.
is still abundant in its natural range but because of declining numbers it is likely to become endangered in the near future. Behavioral characteristics that make them prone to extinction. Some characteristic that cause animals to go extinct are low reproductive rate (k-strategist), specialized niche, narrow distribution, feeds at high trophic level, fixed migratory patterns, rare, commercially valuable, large territories.
because of the billions of years of biological connections leading to the evolution of the human species, we have an inherent genetic kinship with the natural world.
The greatest threat to a species is the loss, degradation, and fragmenting of the place where it lives.
any habitat surrounded by a different one. Most national parks and other nature reserves are habitat islands, many of them encircled by potentially damaging logging, mining, energy extraction, and industrial activities.
by roads, logging, agriculture, and urban development- occurs when a large, continuous area of habitat is reduced in area and divided into smaller, more scattered, and isolated patches.
species that are not on an approved list are denied entry into the country. Prevention is the best way to reduce the threats from invasive species because once they have arrived it is almost impossible to slow their spread.
sharply reducing fish harvests and closing some over fished areas until they recover and we have more information about what levels of fishing can be sustained.
Convention on International Trade in Endangered Species (1977). This treaty, now signed by 169 countries, lists some 900 species that cannot be commercially traded as live specimens or wildlife products because they are in danger of extinction.
reduce international trade in many threatened animals, including elephants, crocodiles, cheetahs, and chimpanzees. But the effects of this treaty are limited because enforcement varies from country to country and convicted violators often pay only small fines.
ESA: Endangered Species Act:
was designed to identify and legally protect endangered species in the United States and abroad. This act is probably the most far-reaching environmental law ever adopted by any nation, and this has made it controversial.
ESA makes it illegal
for Americans to sell or buy any product made from endangered or threatened species or to hunt, kill, collect, or injure such species in the United States.
used to catch fish and shellfish that live on or near the ocean floor. It involves dragging a funnel-shaped net help open at the neck along the ocean bottom; it is weight down with chains or metal plates. This scrapes up almost everything that lies on the ocean floor and often destroys bottom habitats-somewhat like clear-cutting the ocean floor. The large mesh of the net allows most of the small fish to escape but can capture and kill other species such as seals and endangered and threatened sea turtles.
Gill net and Drift net
fish are caught by huge drifting nets that can hang as much as 1,600 feet below the surface and be up to 80 miles long. This method leads to over fishing of the desired species and may trap and kill large quantities of unwanted fish and marine mammals, marine turtles, and seabirds.
involves catching surface-dwelling species such as tune, mackerel, anchovies and herring, which tend to feed in schools near the surface or in shallow areas. Nets used to capture yellowfin tune in the Pacific Ocean have killed large numbers of dolphins that swim on the surface above the tuna. .
Maximum sustained yield
highest rate at which a potentially renewable resource can be used indefinitely without reducing its available supply.
Optimum sustained yield
attempts to take into account interactions with other species and to provide more room for error.
exhaustion of 80% of the estimated supply of a nonrenewable resource. Finding, extracting and processing the remaining 20% usually cost more that it is worth. May also apply to the depletion of a renewable resource, such as fish or a tree.
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