Unit 2 Abiotic and Biotic Parts of Ecosystems La Cañada High School

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APES Unit 2
Abiotic and Biotic Parts of Ecosystems
La Cañada High School
Living in the Environment by Miller, 11th Edition
Matter and Energy Resources: Types
and Concepts
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3-1: Matter: Forms, Structure, and Quality
3-2: Energy: Forms and Quality
3-3: Physical and Chemical Changes and the
Law
of Conservation of Matter
3-4: Nuclear Changes
3-5: The Two Ironclad Laws of Energy
3-6: Connections: Matter and Energy Laws and
Environmental Problems
Matter
Forms, Structure, and Quality



Matter is anything that has mass and takes
up space.
Matter is found in two chemical forms:
elements and compounds.
Various elements, compounds, or both can
be found together in mixtures.
Solid, Liquid, and Gas
Atoms, Ions, and Molecules



Atoms: The smallest unit of matter that is
unique to a particular element.
Ions: Electrically charged atoms or
combinations of atoms.
Molecules: Combinations of two or more
atoms of the same or different elements held
together by chemical bonds.
What are Atoms?


The main building blocks of an atom are
positively charged PROTONS, uncharged
NEUTRONS, and negatively charged
ELECTRONS
Each atom has an extremely small center, or
nucleus, containing protons and neutrons.
http://mediaserv.sus.mcgill.ca/content/2004-Winter/180-Winter/Nuclear/frame0008.htm
Atomic Number and Mass
Number.
 Atomic
number
 The
number of protons in the
nucleus of each of its atoms.
 Mass
 The
number
total number of protons and
neutrons in its nucleus.
Elements are organized through the periodic
table by classifications of metals, metalloids,
and nonmetals
Inorganic Compounds


All compounds not Organic
Ionic Compounds



sodium chloride (NaCl)
sodium bicarbonate (NaOH)
Covalent compounds

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
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hydrogen(H2)
carbon dioxide (CO2)
nitrogen dioxide (NO2)
sulfur dioxide (SO2)
Ammonia (NH3)
Inorganic Compounds


The earth’s crust is
composed of mostly
inorganic minerals
and rock
The crust is the source
of all most
nonrenewable
resource we use: fossil Various combinations of only
eight elements make up the bulk
fuels, metallic
of most minerals.
minerals, etc.
Nonmetallic Elements.
 Carbon
(C), Oxygen (O), Nitrogen
(N), Sulfur (S), Hydrogen (H), and
Phosphorous (P).
 Nonmetallic elements make up
about 99% of the atoms of all
living things.
Ionic Compounds
Structure


Composed of oppositely-charged ions
Network of ions held together by attraction
Ionic bonds

Forces of attraction between opposite charges
Formation of Ionic Compounds

Transfer of electrons between the atoms of
these elements



Atom that is metal loses electrons (oxidation) to
become positive
Atom that is nonmetal gains electrons
(reduction) to become negative
Results in drastic changes to the elements
involved
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/redox.gif
Sodium Chloride



Sodium is a rather "soft" metal solid, with a
silver-grey color
Chlorine is greenish colored gas
When a single electron is transferred
between these elements, their atoms are
transformed via a violent reaction into a
totally different substance called, sodium
chloride, commonly called table salt -- a
white, crystalline, and brittle solid
Covalent Bonds
Formed by two non-metals
 Similar electronegativities
 Neither atom is "strong" enough to steal
electrons from the other
 Therefore, the atoms must share the
electrons

Covalent Bonds

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Chlorine atoms with valence electrons shown
Chlorine atom has seven valence electrons, but
wants eight
When unpaired electron is shared, both atoms now
have a full valence of eight electrons
Individual atoms are independent, but once the
bond is formed, energy is released, and the new
chlorine molecule (Cl2) behaves as a single particle
Organic Compounds

Compounds containing carbon atoms
combined with each other with atoms of
one or more other elements such as
hydrogen, oxygen, nitrogen, sulfur, etc.

Hydrocarbons


Chlorofluorocarbons


Compounds of carbon and hydrogen
Carbon, chlorine, and fluorine atoms
Simple carbohydrates

carbon, hydrogen, oxygen combinations
Organic Compounds
Hydrocarbons
Chlorofluorocarbons
Biological Organic Compounds
Carbohydrates (Glucose)
Protein (Cytochrome P450)
Biological Organic Compounds
Lipid (Triglyceride)
Nucleic Acid (DNA)
Earth’s Crust
Matter Quality



Matter quality is a measure of how useful a
matter resource is, based in its availability and
concentration.
High quality matter is organized, concentrated,
and usually found near the earth’s crust.
Low quality is disorganized, dilute, and has
little potential for use as a matter resource.
High quality & Low quality
HIGH QUALITY
LOW QUALITY
Energy

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Energy is the capacity to do work and
transfer heat.
Energy comes in many forms: light, heat,
and electricity.
Kinetic energy is the energy that matter has
because of its mass and its speed or velocity.
Electromagnetic Spectrum

The range of electromagnetic waves, which differ in
wavelength (distance between successive peaks or
troughs) and energy content.
Kinetic energy.

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
Kinetic energy is the energy that matter has
because of its mass and its speed or velocity.
It is energy in action or motion.
Wind, flowing streams, falling rocks,
electricity, moving car - all have kinetic
energy.
Potential energy


Potential energy is stored energy that is
potential available for use.
Potential energy can be charged to kinetic
energy.
Energy Quality

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Very High: Electricity, Nuclear fission, and
Concentrated sunlight.
High: Hydrogen gas, Natural gas, and Coal.
Moderate: Normal sunlight, and wood.
Low: Low- temperature heat and dispersed
geothermal energy.
Natural Radioactive Decay

A nuclear change in which unstable isotopes
spontaneously emit fast moving particles,
high energy radiation, or both at a fixed
rate

The unstable isotopes are also known as
radioactive isotopes or radioisotopes
Natural Radioactive Decay
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The decay continues until the original isotope
becomes a stable, nonradioactive isotope
Until then, the radiation emitted is damaging
ionizing radiation
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Gamma rays
Alpha particles
Beta particles
After ten half-lifes, the material is said to be clean
Alpha, Beta, Gamma rays
Nuclear Fission


Nuclear change in which nuclei of certain
isotopes with large mass numbers are spilt
apart into lighter nuclei when struck by
neutrons
Each fission releases two or three more
neutrons and energy
Click to see QuickTime Movie of Fission http://www.atomicarchive.com/Movies/Movie4.shtml
Nuclear Fission

Critical Mass

Enough fissionable
nuclei available for
multiple fission reactions
to occur

Chain Reaction

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Multiple fissions within
a critical mass
Releases huge amounts
of energy
Atomic Bomb or
Nuclear Power Plant
The “Law of Conservation of
Matter and Energy”


In any nuclear change, the total amount of
matter and energy involved remains the
same.
E = mc2

The energy created by the release of the strong
nuclear forces for 1 kilogram of matter will
produce enough energy to elevated the
temperature of all the water used in the Los
Angeles basin in one day by 10,000oC
What is Nuclear Fusion?

Nuclear Fusion is a nuclear change in which
two isotopes of light elements, such as
hydrogen, are forced together at extremely
high temperatures until they fuse to form a
heavier nucleus, releasing energy in the
process.
First Law of Thermodynamics
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In all physical and chemical changes
Energy is neither created nor destroyed
But it may be converted from one form to
another
Second Law of Thermodynamics
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When energy is changed from one form to
another
Some of the useful energy is always
degraded to lower-quality, more dispersed,
less useful energy
Also known as Law of Entropy
High Waste Societies
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
People continue to use and waste more and
more energy and matter resources at an
increasing rate
At some point, high-waste societies will
become
 UNSUSTAINABLE!
Goals of Matter Recycling Societies
To allow economic growth to continue without
depleting matter resources or producing
excess pollution
Matter Recycling Societies
Advantages
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Saves Energy
Buys Time
Disadvantages
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Requires high-quality energy
which cannot be recycled
Adds waste heat
No infinite supply of affordable
high-quality energy available
Limit to number of times a
material can be recycled
Low Waste Societies

Works with nature to reduce throughput

Based on energy flow and matter recycling
Low Waste Societies Function
1. Reuse/recycle most nonrenewable
matter resources
2. Use potentially renewable resources no
faster than they are replenished
3. Use matter and energy resources
efficiently
Low Waste Societies Function
4. Reduce unnecessary consumption
5. Emphasize pollution prevention and
waste reduction
6. Control population growth
Unit 2, Chapter 4
Ecology, Ecosystems, and Food
Webs
Chapter 4
Ecology, Ecosystems, and Food Webs
4-1 Ecology and Life
 4-2 Earth’s Life-Support Systems
 4-3 Ecosystem Concept
 4-4 Food Webs and Energy Flow in
Ecosystems
 4-5 How do Ecologists learn about
Ecosystems?
 4-6 Ecosystem Services and Sustainability

4-1 Ecology and Life
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Ecology- study of relationships between
organisms and their environment
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Ecology examines how organisms interact with
their nonliving (abiotic) environment such as
sunlight, temperature, moisture, and vital nutrients
Biotic interaction among organisms, populations,
communities, ecosystems, and the ecosphere
Distinction between Species

Wild species- one that exists as
a population of individuals in a
natural habitat, ideally similar
to the one in which its ancestors
evolved

Domesticated species- animals
such as cows, sheep, food
crops, animals in zoos
Vocabulary
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Population
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Group of interacting individuals of the same
species that occupy a specific area at the same time
Genetic Diversity

Populations that are dynamic groups that change in
size, age distribution, density, and genetic
composition as a result of changes in
environmental conditions
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Habitat
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Community
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Complex interacting network of plants, animals,
and microorganisms
Ecosystem
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Place where a population or individual organism
naturally lives
Community of different species interacting with
one another and with their nonliving environment
of matter and energy
Ecosphere or Biosphere

All earth's ecosystems
What is Life?

All life shares a set of basic
characteristics
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
Made of cells that have highly
organized internal structure and
functions
Characteristic types of
deoxyribonucleic acid (DNA)
molecules in each cell
Living Organisms
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Capture and transform matter and energy from
their environment to supply their needs for
survival, growth, and reproduction
Maintain favorable internal conditions, despite
changes in their external environment through
homeostasis, if not overstressed
Living Organisms
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Perpetuate themselves through reproduction
Adapt to changes in environmental conditions
through the process of evolution
www.sws.uiuc.edu/nitro/biggraph.asp
4-2 Geosphere
The Earth contains several
layers or concentric spheres
Lithosphere

Crust and upper mantle

Crust

Outermost, thin silicate zone, eight
elements make up 98.5% of the
weight of the earth’s crust
4-2 Geosphere

Mantle

Surrounded by a thick, solid zone,
largest zone, rich with iron, silicon,
oxygen, and magnesium, very hot
Core


Innermost zone, mostly iron, solid
inner part, surrounded by a liquid
core of molten material
Inner Core is hotter than surface of
the Sun
4-2 Atmosphere

Thin envelope of air
around the planet

Troposphere
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extends about 17 kilometers
above sea level, contains
nitrogen (78%),
oxygen(21%), and is where
weather occurs
Stratosphere

17-48 kilometers above sea
level, lower portions
contains enough ozone (O3)
to filter out most of the
sun’s ultraviolet radiation
4-2 Hydrosphere
Consists of the earth’s
liquid water, ice, and
water vapor in the
atmosphere
What Sustains
Life on Earth?

Life on the earth depends on three
interconnected factors

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One-way flow of high-quality energy
from the sun
Cycling of matter or nutrients (all
atoms, ions, or molecules needed for
survival by living organisms), through
all parts of the ecosphere
Gravity, which allows the planet to
hold onto its atmosphere and causes
the downward movement of chemicals
in the matter cycles
Sun
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Fireball of hydrogen (72%) and helium
(28%)
Nuclear fusion
Sun has existed for 6 billion years
Sun will stay for another 6.5 billion years
Visible light that reaches troposphere is
the ultraviolet ray which is not absorbed
in ozone
Solar Energy
72% of solar energy warms the lands
 0.023% of solar energy is captured by green
plants and bacteria
 Powers the cycling of matter and weather
system
 Distributes heat and fresh water

www.bom.gov.au/lam/climate/levelthree/ climch/clichgr1.htm
Type of Nutrients

Nutrient
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Macronutrient
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Any atom, ion, or molecule an organism needs to live grow
or reproduce
Ex: carbon, oxygen, hydrogen, nitrogen… etc
nutrient that organisms need in large amount
Ex: phosphorus, sulfur, calcium, iron … etc
Micronutrient


nutrient that organism need in small amount
Ex: zinc, sodium, copper… etc
Biomes – Large regions
characterized by
distinct climate, and
specific life-forms
Climate – Long-term
weather; main factor
determining what type of life
will be in a certain area.
Ecosphere Separation

The Ecosphere and it’s ecosystem can be
separated into two parts

Abiotic- nonliving, components
Ex: air, water, solar energy
 Physical and chemical factors that influence living
organisms


Biotic- living, components

Ex: plants and animals
Range of Tolerance

Variations in it’s physical and chemical
environment
Differences in genetic makeup, health, and
age.
 Ex: trout has to live in colder water than
bass

Limiting Factor

More important than others in regulating
population growth


Ex: water light, and soil
Lacking water in the desert can limit the growth of
plants
Limiting Factor Principle

too much or too little of any abiotic factor can
limit growth of population, even if all the other
factors are at optimum (favorable) range of
tolerance.

Ex: If a farmer plants corn in phosphorus-poor
soil, even if water, nitrogen are in a optimum
levels, corn will stop growing, after it uses up
available phosphorus.
Dissolved Oxygen Content

Amount of oxygen
gas dissolved in a
given volume of
water at a particular
temperature and
pressure.

Limiting factor of
aquatic ecosystem
Salinity

amount of salt dissolved
in given volume of
water
Living Organisms in Ecosystem
Producers or autotrophs- makes their
own food from compound obtained
from environment.
 Ex:
sun
plant gets energy or food from
Living Organisms in Ecosystem
Photosynthesis- ability of producer to convert
sunlight, abiotic nutrients to sugars and other
complex organic compounds

Chlorophyll- traps solar energy and converts into
chemical energy

Producer transmit 1-5% of
absorbed energy into
chemical energy, which is
stored in complex
carbohydrates, lipids,
proteins and nucleic acid in
plant tissue
Chemosynthesis
Bacteria can convert simple
compounds from their
environment into more
complex nutrient compound
without sunlight


Ex: becomes consumed by
tubeworms, clams, crabs
Bacteria can survive in great
amount of heat
Consumers or Heterotrophs

Obtain energy and nutrients by feeding on
other organisms or their remains
Consumers

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Herbivores (plant-eaters) or primary consumers
Feed directly on producers

Deer, goats, rabbits
http://www.holidays.net/easter/bunny1.htm
Consumers


Carnivores (meat
eater) or secondary
consumers
Feed only on
primary consumer

Lion, Tiger
Consumers


Tertiary (higherlevel) consumer
Feed only on other
carnivores

Wolf
Consumers

Omnivoresconsumers that eat
both plants and
animals

Ex: pigs, humans,
bears
Consumers

Scavengers- feed on dead organisms

Vultures, flies, crows, shark
Consumers

Detritivores- live off
detritus


Detritus parts of dead
organisms and wastes of
living organisms.
Detritus feeders- extract
nutrients from partly
decomposed organic
matter plant debris, and
animal dung.
Consumers

Decomposers - Fungi and
bacteria break down and
recycle organic materials
from organisms’ wastes
and from dead organisms


Food sources for worms
and insects
Biodegradable - can be
broken down by
decomposers
Respiration

Aerobic Respiration



Uses oxygen to convert organic nutrients back into
carbon dioxide and water
Glucose + oxygen  Carbon dioxide + water +
energy
Anaerobic Respiration or Fermentation

Breakdown of glucose in absence of oxygen
Food Chain

Food Chain-Series of organisms
in which each eats or
decomposes the preceding one


Decomposers complete the cycle
of matter by breaking down
organic waste, dead animal. Plant
litter and garbage.
Whether dead or alive organisms
are potential (standard) sources of
food for other organisms.
Second Law of Energy

Organisms need high quality chemical energy
to move, grow and reproduce, and this energy
is converted into low-quality heat that flows
into environment


Trophic levels or feeding levels- Producer is a
first trophic level, primary consumer is second
trophic level, secondary consumer is third.
Decomposers process detritus from all trophic
levels.
Food Web


Complex network
of interconnected
food chains
Food web and
chains


One-way flow of
energy
Cycling of
nutrients through
ecosystem
Food Webs

Grazing Food Webs



Energy and nutrients
move from plants to
herbivores
Then through an array
of carnivores
Eventually to
decomposers
(100,000 Units of Energy)
Food Webs

Grazing Food Webs



Energy and nutrients
move from plants to
herbivores
Then through an array
of carnivores
Eventually to
decomposers
(1,000 Units of Energy)
Food Webs

Grazing Food Webs



Energy and nutrients
move from plants to
herbivores
Then through an array
of carnivores
Eventually to
decomposers
(100 Units of Energy)
Food Webs

Grazing Food Webs



Energy and nutrients
move from plants to
herbivores
Then through an array
of carnivores
Eventually to
decomposers
(10 Units of Energy)
Food Webs

Grazing Food Webs



Energy and nutrients
move from plants to
herbivores
Then through an array
of carnivores
Eventually to
decomposers
(1 Units of Energy)
Food Webs

Detrital Food Webs


Organic waste material
or detritus is the major
food source
Energy flows mainly
from producers
(plants) to
decomposers and
detritivores.
Pyramid of Energy Flow


More steps or trophic levels in food chain or web, greater loss
of usable energy as energy flows through trophic levels
More trophic levels the Chains or Webs have more energy is
consumed after each one. That’s why food chains and webs
rarely have more than 4 steps
Pyramid of Energy Flow


Loss of usable energy as energy flows through
trophic levels of food chains and webs
Rarely have more than 4 steps
Biomass

Dry weight of all organic matter contained in
organisms.

Biomass is measured in dry weight



Water is not source of energy or nutrient
Biomass of first trophic levels is dry mass of all
producers
Useable energy transferred as biomass varies from
5%-20% (10% standard)
Pyramid of Biomass
Storage of biomass at various trophic levels of
ecosystem
Pyramid of Numbers
Number of organisms at each trophic level
http://www.nicksnowden.net/Module_3_pages/ecosystems_energy_flows.htm
Gross Primary Productivity (GPP)
Rate in which
producers
convert solar
energy into
chemical
energy
(biomass) in a
given amount
of time
Net Primary Productivity (NPP)

Rate in which energy for use by consumers is
stored in new biomass of plants



Measured in kilocalories per square meter per year
or grams in biomass
NPP is the limit determining the planet’s carrying
capacity for all species.
59% of NPP occurs in land / 41% occurs in ocean
Ecological Efficiency

Percentage of energy transferred from one
trophic level to another.

10% ecological efficiency
1,000,000 units of energy from sun
 10,000 units available for green plants (photosynthesis)
 1000 units for herbivores
 100 units for primary carnivores
 10 units for secondary carnivores

Studying Ecosystems

FIELD RESEARCH




LABORATORY RESEARCH




Going into nature and observing/measuring the structure of ecosystems
Majority of what we know now comes from this type
Disadvantage is that it is expensive, time-consuming, and difficult to carry out
experiments due to many variables
Set up, observation, and measurement of model ecosystems under laboratory
conditions
Conditions can easily be controlled and are quick and cheap
Disadvantage is that it is never certain whether or not result in a laboratory will
be the same as a result in a complex, natural ecosystem
SYSTEMS ANALYSIS


Simulation of ecosystem rather than study real ecosystem
Helps understand large and very complicated systems
Ecosystem Importance
Ecosystem services are the natural
services or earth capital that support life
on the earth
 Essential to the quality of human life and
to the functioning of the world’s
economies

Ecosystem Importance

Ecosystem services include:





Controlling and moderating climate
Providing and renewing air, water, soil
Recycling vital nutrients through chemical cycling
Providing renewable and nonrenewable energy
sources and nonrenewable minerals
Furnishing people with food, fiber, medicines,
timber, and paper
Ecosystem Importance

Ecosystem services include





Pollinating crops and other plant species
Absorbing, diluting, and detoxifying many
pollutants and toxic chemicals
Helping control populations of pests and disease
organisms
Slowing erosion and preventing flooding
Providing biodiversity of genes and species
Why Is Biodiversity So Important?




Food, wood, fibers, energy,
raw materials, industrial
chemicals, medicines, …
Provides for billions of
dollars in the global
economy
Provides recycling,
purification, and natural pest
control
Represents the millions of
years of adaptation, and is
raw material for future
adaptations
Two Principles of Ecosystem
Sustainability


Use renewable solar
energy as energy
source
Efficiently recycle
nutrients organisms
need for survival,
growth, and
reproduction
Unit 2, Chapter 5
Nutrient Cycles and Soils
Matter Cycling in Ecosystems
 Nutrient
 Natural
or Biogeochemical Cycles
processes that recycle
nutrients in various chemical forms
in a cyclic manner from the
nonliving environment to living
organisms and back again
Nutrient Cycles (Closed System)
Energy Flow (Open System)
 Water
 Sulfur
 Carbon
 Rock
 Nitrogen
 Soil
 Phosphorus
 Energy
Flow
Biogeochemical Cycle Locations

Hydrosphere



Atmospheric



Water in the form of ice, liquid, and vapor
Operates local, regional, and global levels
Large portion of a given element (i.e. Nitrogen gas) exists in
gaseous form in the atmosphere
Operates local, regional, and global levels
Sedimentary


The element does not have a gaseous phase or its gaseous
compounds don’t make up a significant portion of its supply
Operates local and regional basis
Nutrient Cycling & Ecosystem
Sustainability

Natural ecosystems tend to balance


Humans are accelerating rates of flow of mater



Nutrients are recycled with reasonable efficiency
Nutrient loss from soils
Doubling of normal flow of nitrogen in the nitrogen
cycle is a contributes to global warming, ozone
depletion, air pollution, and loss of biodiversity
Isolated ecosystems are being influenced by
human activities
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