Fresh water or freshwater is any naturally occurring liquid or frozen
water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). It is vital for all known forms of , even though it provide ...

containing low
concentration
In chemistry
Chemistry is the study of the properties and behavior of . It is a that covers the that make up matter to the composed of s, s and s: their composition, structure, properties, behavior and the changes they undergo during ...

s of dissolved
salts
In chemistry
Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds composed of atoms, ...
and other
total dissolved solids
Total dissolved solids (TDS) is a measure of the dissolved combined content of all inorganic and organic substances present in a liquid in molecular, ionized, or micro-granular ( colloidal sol) suspended form. TDS concentrations are often repor ...
. Although the term specifically excludes
seawater
Seawater, or salt water, is water
Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of E ...

and
brackish water
Brackish water, also sometimes termed brack water, is water occurring in a natural environment having more salinity
Salinity () is the saltiness or amount of dissolved in a body of , called (see also ). It is usually measured in g/L or g/kg ...
, it does include non-
salty mineral-rich waters such as
chalybeate
Mineral stains, Rosedale, North Yorkshire, Rosedale Cliffs – marks caused by chalybeate waters
Chalybeate () waters, also known as Iron oxide, ferruginous waters, are mineral spring waters containing salts of iron.
Name
The word "chalybeate" ...
springs. Fresh water may encompass
and
meltwater
Meltwater is water released by the melting of snow or ice, including glaciers, glacial ice, tabular icebergs and ice shelf, ice shelves over oceans. Meltwater is often found in the ablation zone of glaciers, where the rate of snow cover is reduci ...
in
ice sheet
In , an ice sheet, also known as a continental glacier, is a mass of that covers surrounding terrain and is greater than . The only current ice sheets are in and ; during the at (LGM) the covered much of , the ice sheet covered and the c ...

s,
ice cap
In glaciology
Lateral moraine on a glacier joining the Gorner Glacier, Zermatt">Gorner_Glacier.html" ;"title="moraine on a glacier joining the Gorner Glacier">moraine on a glacier joining the Gorner Glacier, Zermatt, Swiss Alps. The moraine is ...
s,
glacier
A glacier (; ) is a persistent body of dense ice
Ice is into a state. Depending on the presence of such as particles of soil or bubbles of air, it can appear transparent or a more or less bluish-white color.
In the , ice is abunda ...

s,
snowfield
A snow field, snowfield or neve is an accumulation of permanent snow and ice, typically found above the snow line
The climatic snow line is the boundary between a snow
Snow comprises individual ice crystals that grow while suspended i ...
s and
iceberg
An iceberg is a piece of freshwater
Fresh water or freshwater is any naturally occurring liquid or frozen water
Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and Color ...

s, natural
precipitation
In meteorology
Meteorology is a branch of the (which include and ), with a major focus on . The study of meteorology dates back , though significant progress in meteorology did not begin until the 18th century. The 19th century saw mod ...

s such as
rain
Rain is liquid water in the form of droplet
Rain water flux from a canopy. Among the forces that govern drop formation: cohesion, Van der Waals force">Cohesion_(chemistry).html" ;"title="surface tension, Cohesion (chemistry)">cohesion, ...

fall,
snowfall
Snow comprises individual ice
Ice is water
Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the mai ...

,
hail
Hail is a form of solid precipitation
In meteorology
Meteorology is a branch of the atmospheric sciences
Atmospheric science is the study of the Earth's atmosphere
File:Atmosphere gas proportions.svg, Composition of Earth's atmo ...

/
and
graupel
Graupel (; ), also called soft hail, corn snow, hominy snow, or snow pellets, is precipitation
In meteorology
Meteorology is a branch of the atmospheric sciences
Atmospheric science is the study of the Earth's atmosphere
File:Atmo ...

, and
surface runoff
Surface runoff (also known as overland flow) is the flow of water
Water (chemical formula H2O) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydros ...
s that form inland
bodies of water
A body of water or waterbody (often spelled water body) is any significant accumulation of water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known l ...
such as
wetland
A wetland is a distinct ecosystem
An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles ...

s,
pond
A pond is an area filled with water, either natural or Artificiality, artificial, that is smaller than a lake. Ponds are small bodies of freshwater with shallow and still water, marsh, and aquatic plants.Clegg, J. (1986). Observer's Book of ...

s,
lake
A lake is an area filled with water, localized in a basin, surrounded by land
Land is the solid surface of Earth that is not permanently submerged in water. Most but not all land is situated at elevations above sea level (variable ove ...

s,
river
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

s,
stream
A stream is a body of water
(Lysefjord) in Norway
Norway, officially the Kingdom of Norway,Names in the official and recognised languages: Bokmål
Bokmål (, ; literally "book tongue") is an official written standard for the No ...

s, as well as
groundwater
Groundwater is the water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). It is vital for all known form ...

contained in
aquifer
An aquifer is an underground layer of -bearing , rock fractures or unconsolidated materials (, , or ). can be extracted using a water . The study of water flow in aquifers and the characterization of aquifers is called . Related terms include a ...

s,
subterranean
Subterranean(s) or The Subterranean(s) may refer to:
* Subterranea (geography), underground structures, both natural and man-made
Literature
* Subterranean (novel), ''Subterranean'' (novel), a 1998 novel by James Rollins
* ''Subterranean Magazi ...
river
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...
s and
lake
A lake is an area filled with water, localized in a basin, surrounded by land
Land is the solid surface of Earth that is not permanently submerged in water. Most but not all land is situated at elevations above sea level (variable ove ...
s.
Water is critical to the survival of all living
organism
In biology
Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular interactions, Physiology, physiological ...

s. Many organisms can thrive on salt water, but the great majority of
higher plant
Vascular plants (from Latin ''vasculum'': duct), also known as Tracheophyta (the tracheophytes , from Greek τραχεῖα ἀρτηρία ''trācheia artēria'' 'windpipe' + φυτά ''phutá'' 'plants'), form a large group of plants ( 300,000 a ...
s and most
insect
Insects (from Latin
Latin (, or , ) is a classical language
A classical language is a language
A language is a structured system of communication
Communication (from Latin ''communicare'', meaning "to share" or "to be in ...

s,
amphibian
Amphibians are ectothermic, tetrapod vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial animal, ter ...
s,
reptile
Reptiles, as most commonly defined, are the animals in the class
Class or The Class may refer to:
Common uses not otherwise categorized
* Class (biology), a taxonomic rank
* Class (knowledge representation), a collection of individuals or ...

s,
mammal
Mammals (from Latin
Latin (, or , ) is a classical language
A classical language is a language
A language is a structured system of communication
Communication (from Latin ''communicare'', meaning "to share" or "to be i ...
s and
bird
Birds are a group of warm-blooded vertebrate
Vertebrates () comprise all species of animal
Animals (also called Metazoa) are multicellular eukaryotic organisms that form the Kingdom (biology), biological kingdom Animalia. With ...

s need fresh water to survive.
Fresh water is not always
potable water
Drinking water, also known as potable water, is water
Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main ...

, that is, water safe to drink by
human
Humans (''Homo sapiens'') are the most abundant and widespread species
In biology, a species is the basic unit of biological classification, classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A speci ...

s. Much of the
earth
Earth is the third planet from the Sun and the only astronomical object known to harbour and support life. 29.2% of Earth's surface is land consisting of continents and islands. The remaining 70.8% is Water distribution on Earth, covered wi ...

's fresh water (on the surface and groundwater) is to a substantial degree unsuitable for human consumption without some treatment. Fresh water can easily become
or due to naturally occurring processes, such as erosion.
Fresh water is a renewable and variable, but finite
natural resource
Natural resources are resource
Resource refers to all the materials available in our environment which help us to satisfy our needs and wants. Resources can broadly be classified upon their availability — they are classified into renewabl ...
. Fresh water can only be replenished through the process of the
water cycle
The water cycle, also known as the hydrologic cycle or the hydrological cycle, is a biogeochemical cycle
In ecology
Ecology (from el, οἶκος, "house" and el, -λογία, label=none, "study of") is the study of the relationships ...

, in which water from seas, lakes, forests, land, rivers and
reservoirs
A reservoir (; from French language, French ''réservoir'' ) is most commonly an enlarged natural or artificial lake created using a dam to water storage, store water.
Reservoirs can be created in a number of ways, including controlling a wate ...

evaporates, forms
cloud
In meteorology, a cloud is an aerosol consisting of a visible mass of minute liquid drop (liquid), droplets, ice crystals, frozen crystals, or other particulates, particles suspended in the atmosphere of a planetary body or similar space. Wate ...

s, and returns inland as precipitation. Locally, however, if more fresh water is consumed through human activities than is naturally restored, this may result in reduced fresh water availability (or
water scarcity
Water scarcity (water stress or water crisis) is the lack of fresh water resources to meet the standard water demand. Humanity is facing a water crisis, due to unequal distribution (exacerbated by climate change
Climate change inclu ...

) from surface and underground sources and can cause serious damage to surrounding and associated environments.
Water pollution
Water pollution (or aquatic pollution) is the contamination of water bodies
( Lysefjord) in Norway
Norway ( nb, ; nn, ; se, Norga; smj, Vuodna; sma, Nöörje), officially the Kingdom of Norway, is a Nordic countries, Nordic c ...

and subsequent
eutrophication
Eutrophication (from Greek ''eutrophos'', "well-nourished") is the process by which an entire body of water
(Lysefjord) in Norway
Norway, officially the Kingdom of Norway,Names in the official and recognised languages: Bokmål
Bokmå ...

also reduces the availability of fresh water.
Definitions
Numerical definition
Fresh water can be defined as water with less than 1000
parts per million
In science
Science (from the Latin word ''scientia'', meaning "knowledge") is a systematic enterprise that Scientific method, builds and Taxonomy (general), organizes knowledge in the form of Testability, testable explanations and predictio ...
(ppm) of dissolved
salt
Salt is a mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure fo ...
s.
Other sources give higher upper salinity limits for fresh water, e.g. 1000 ppm or 3000 ppm.
Systems

Fresh water habitats are classified as either
lentic systems, which are the stillwaters including
pond
A pond is an area filled with water, either natural or Artificiality, artificial, that is smaller than a lake. Ponds are small bodies of freshwater with shallow and still water, marsh, and aquatic plants.Clegg, J. (1986). Observer's Book of ...

s, lakes,
swamp
A swamp is a forested wetland
A wetland is a distinct ecosystem that is flooded by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (Anoxic waters, anoxic) processes pre ...

s and
mire
, one of the largest fens in Estonia.
A mire, peatland, or quagmire is a wetland
A wetland is a distinct ecosystem that is flooded by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results i ...

s;
lotic
River ecosystem
An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Ener ...
which are running-water systems; or
groundwater
Groundwater is the water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). It is vital for all known form ...

s which flow in rocks and
aquifer
An aquifer is an underground layer of -bearing , rock fractures or unconsolidated materials (, , or ). can be extracted using a water . The study of water flow in aquifers and the characterization of aquifers is called . Related terms include a ...

s. There is, in addition, a zone which bridges between groundwater and lotic systems, which is the
hyporheic zone
The hyporheic zone is the region of sediment and porous space beneath and alongside a stream bed
A stream is a body of water
( Lysefjord) in Norway
Norway ( nb, ; nn, ; se, Norga; smj, Vuodna; sma, Nöörje), officially the ...
, which underlies many larger rivers and can contain substantially more water than is seen in the open channel. It may also be in direct contact with the underlying underground water.
Sources
The original source of almost all fresh water is
precipitation
In meteorology
Meteorology is a branch of the (which include and ), with a major focus on . The study of meteorology dates back , though significant progress in meteorology did not begin until the 18th century. The 19th century saw mod ...
from the
atmosphere
An atmosphere (from the greek words ἀτμός ''(atmos)'', meaning 'vapour', and σφαῖρα ''(sphaira)'', meaning 'ball' or 'sphere') is a layer or a set of layers of gases surrounding a planet or other material body, that is held in ...

, in the form of
mist
Mist is a phenomenon caused by small droplets of water
Water (chemical formula H2O) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and ...

,
rain
Rain is liquid water in the form of droplet
Rain water flux from a canopy. Among the forces that govern drop formation: cohesion, Van der Waals force">Cohesion_(chemistry).html" ;"title="surface tension, Cohesion (chemistry)">cohesion, ...

and
snow
Snow comprises individual ice
Ice is water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). ...

. Fresh water falling as mist, rain or snow contains materials dissolved from the
atmosphere
An atmosphere (from the greek words ἀτμός ''(atmos)'', meaning 'vapour', and σφαῖρα ''(sphaira)'', meaning 'ball' or 'sphere') is a layer or a set of layers of gases surrounding a planet or other material body, that is held in ...

and material from the sea and land over which the rain bearing clouds have traveled. The precipitation leads eventually to the formation of
water bodies
( Lysefjord) in Norway
Norway ( nb, ; nn, ; se, Norga; smj, Vuodna; sma, Nöörje), officially the Kingdom of Norway, is a Nordic countries, Nordic country in Northern Europe whose mainland territory comprises the western and nort ...

that humans can use as sources of freshwater:
pond
A pond is an area filled with water, either natural or Artificiality, artificial, that is smaller than a lake. Ponds are small bodies of freshwater with shallow and still water, marsh, and aquatic plants.Clegg, J. (1986). Observer's Book of ...

s,
lake
A lake is an area filled with water, localized in a basin, surrounded by land
Land is the solid surface of Earth that is not permanently submerged in water. Most but not all land is situated at elevations above sea level (variable ove ...

s,
rain
Rain is liquid water in the form of droplet
Rain water flux from a canopy. Among the forces that govern drop formation: cohesion, Van der Waals force">Cohesion_(chemistry).html" ;"title="surface tension, Cohesion (chemistry)">cohesion, ...

fall,
river
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

s,
stream
A stream is a body of water
(Lysefjord) in Norway
Norway, officially the Kingdom of Norway,Names in the official and recognised languages: Bokmål
Bokmål (, ; literally "book tongue") is an official written standard for the No ...

s, and
groundwater
Groundwater is the water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). It is vital for all known form ...

contained in underground
aquifer
An aquifer is an underground layer of -bearing , rock fractures or unconsolidated materials (, , or ). can be extracted using a water . The study of water flow in aquifers and the characterization of aquifers is called . Related terms include a ...

s.
In coastal areas fresh water may contain significant concentrations of salts derived from the sea if windy conditions have lifted drops of seawater into the rain-bearing clouds. This can give rise to elevated concentrations of
sodium
Sodium is a chemical element
In chemistry, an element is a pure Chemical substance, substance consisting only of atoms that all have the same numbers of protons in their atomic nucleus, nuclei. Unlike chemical compounds, chemical eleme ...

,
chloride
The chloride ion
An ion () is an atom
An atom is the smallest unit of ordinary matter
In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects th ...

,
magnesium
Magnesium is a chemical element
upright=1.0, 500px, The chemical elements ordered by link=Periodic table
In chemistry
Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science ...

and
sulfate
The sulfate or sulphate ion is a polyatomic anion
An ion () is an atom
An atom is the smallest unit of ordinary matter
In classical physics and general chemistry, matter is any substance that has mass and takes up space by having ...

as well as many other compounds in smaller concentrations.
In
desert
A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to the processes of ...

areas, or areas with impoverished or dusty soils, rain-bearing winds can pick up
sand
Sand is a granular material composed of finely divided rock (geology), rock and mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer ...

and
dust
Dust is made of s of solid . On Earth, it generally consists of particles in the that come from various sources such as lifted by wind (an ), , and . Dust in homes is composed of about 20–50% dead . The rest, and in offices, and other ...
and this can be deposited elsewhere in precipitation and causing the freshwater flow to be measurably contaminated both by insoluble solids but also by the soluble components of those soils. Significant quantities of
iron
Iron () is a chemical element
In chemistry
Chemistry is the study of the properties and behavior of . It is a that covers the that make up matter to the composed of s, s and s: their composition, structure, properties, behav ...

may be transported in this way including the well-documented transfer of iron-rich rainfall falling in Brazil derived from sand-storms in the
Sahara
The Sahara (, ; ar, الصحراء الكبرى, ', 'the Greatest Desert') is a desert on the African continent
Africa is the world's second-largest and second-most populous continent
A continent is any of several large landma ...

in
north Africa
North Africa or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in th ...

.
Water distribution
Saline water in
ocean
The ocean (also the sea
The sea, connected as the world ocean or simply the ocean
The ocean (also the sea or the world ocean) is the body of salt water which covers approximately 71% of the surface of the Earth. s,
sea
The sea, connected as the world ocean or simply the ocean
The ocean (also the sea or the world ocean) is the body of salt water which covers approximately 71% of the surface of the Earth.

s and saline
groundwater
Groundwater is the water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). It is vital for all known form ...

make up about 97% of all the water on
Earth
Earth is the third planet from the Sun and the only astronomical object known to harbour and support life. 29.2% of Earth's surface is land consisting of continents and islands. The remaining 70.8% is Water distribution on Earth, covered wi ...

. Only 2.5–2.75% is fresh water, including 1.75–2% frozen in
glacier
A glacier (; ) is a persistent body of dense ice
Ice is into a state. Depending on the presence of such as particles of soil or bubbles of air, it can appear transparent or a more or less bluish-white color.
In the , ice is abunda ...

s,
ice
Ice is water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). It is vital for all known forms of , eve ...

and snow, 0.5–0.75% as fresh groundwater and
soil
Soil is a mixture
In chemistry
Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, comp ...

moisture, and less than 0.01% of it as
surface water
Surface water is water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). It is vital for all known forms of ...
in
lake
A lake is an area filled with water, localized in a basin, surrounded by land
Land is the solid surface of Earth that is not permanently submerged in water. Most but not all land is situated at elevations above sea level (variable ove ...

s,
swamp
A swamp is a forested wetland
A wetland is a distinct ecosystem that is flooded by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (Anoxic waters, anoxic) processes pre ...

s and
river
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

s. Freshwater lakes contain about 87% of this fresh surface water, including 29% in the
African Great Lakes
The African Great Lakes ( sw, Maziwa Makuu) are a series of lakes constituting the part of the Rift Valley lakes in and around the East African Rift. They include Lake Victoria, the List of lakes by area, second-largest fresh water lake in the wo ...

, 22% in
Lake Baikal
Lake Baikal (; russian: Oзеро Байкал, Ozero Baykal ; bua, Байгал далай, Baigal dalai; mn, Байгал нуур, Baigal nuur) is a rift lake
A rift lake is a lake
A lake is an area filled with water, localized in ...

in Russia, 21% in the
North American Great Lakes
File:Location of the Great Lakes in North America.jpg, upright=1.3, Location in North America
The Great Lakes, also called the Great Lakes of North America or the Laurentian Great Lakes, are a series of large interconnected Fresh water, fresh ...
, and 14% in other lakes. Swamps have most of the balance with only a small amount in rivers, most notably the
Amazon River
The Amazon River (, ; es, Río Amazonas, pt, Rio Amazonas) in South America
South America is a entirely in the and mostly in the , with a relatively small portion in the . It can also be described as the southern of a single con ...

. The atmosphere contains 0.04% water. In areas with no fresh water on the ground surface, fresh water derived from
precipitation
In meteorology
Meteorology is a branch of the (which include and ), with a major focus on . The study of meteorology dates back , though significant progress in meteorology did not begin until the 18th century. The 19th century saw mod ...
may, because of its lower density, overlie saline ground water in lenses or layers. Most of the world's fresh water is frozen in
ice sheet
In , an ice sheet, also known as a continental glacier, is a mass of that covers surrounding terrain and is greater than . The only current ice sheets are in and ; during the at (LGM) the covered much of , the ice sheet covered and the c ...

s. Many areas have very little fresh water, such as
desert
A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to the processes of ...

s.
Freshwater ecosystems
Threats and challenges
The increase in the world population and the increase in per capita water use puts increasing strains on the finite resources availability of clean fresh water. The response by
freshwater ecosystem
Fresh water (or freshwater) is any naturally occurring water
Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is ...
s to a
changing climate can be described in terms of three interrelated components: water quality, water quantity or volume, and water timing. A change in one often leads to shifts in the others as well. However, National Geographic suggests limiting our own water consumption to combat the ongoing water crisis.
Limited resource
Minimum streamflow
An important concern for hydrological ecosystems is securing minimum
streamflow
Streamflow, or channel runoff, is the flow of water
Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main cons ...

, especially preserving and restoring
instream water allocations. Fresh water is an important natural resource necessary for the survival of all
ecosystem
An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syst ...

s. The use of water by humans for activities such as irrigation and industrial applications can have adverse impacts on down-stream ecosystems.
Fresh water withdrawal is the quantity of water removed from available sources for use in any purpose, excluding evaporation losses. Water drawn off is not necessarily entirely consumed and some portion may be returned for further use downstream.
Water pollution
Global goals for conservation
The
Sustainable Development Goals
The Sustainable Development Goals (SDGs) or Global Goals are a collection of 17 interlinked global goals designed to be a "blueprint to achieve a better and more sustainable
Sustainability is the capacity to endure in a relatively ongoing w ...

are a collection of 17 interlinked global goals designed to be a "blueprint to achieve a better and more
sustainable
Sustainability is the capacity to endure in a relatively ongoing way across various domains of life. In the 21st century
The 21st (twenty-first) century is the current century in the '' Anno Domini'' era or Common Era, in accordance with the ...

future for all".
[United Nations (2017) Resolution adopted by the General Assembly on 6 July 2017, Work of the Statistical Commission pertaining to the 2030 Agenda for Sustainable Development]
A/RES/71/313
Targets on freshwater conservation are included in
(Clean water and sanitation) and
(Life on land). For example, Target 6.4 is formulated as "By 2030, substantially increase
water-use efficiency
Water-use efficiency (WUE) refers to the ratio of water used in plant metabolism to water lost by the plant (botanical), plant through transpiration. Two types of water-use efficiency are referred to most frequently:
*photosynthesis, photosynthet ...
across all sectors and ensure sustainable withdrawals and
supply of freshwater to address water scarcity and substantially reduce the number of people suffering from
water scarcity
Water scarcity (water stress or water crisis) is the lack of fresh water resources to meet the standard water demand. Humanity is facing a water crisis, due to unequal distribution (exacerbated by climate change
Climate change inclu ...

."
Another target, Target 15.1, is: "By 2020, ensure the conservation, restoration and sustainable use of terrestrial and inland
freshwater ecosystem
Fresh water (or freshwater) is any naturally occurring water
Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is ...
s and their services, in particular forests,
wetland
A wetland is a distinct ecosystem
An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles ...

s,
mountain
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. A mountain differs from a plateau in having a limited summit area, and is larger than a hill, typically rising at least ...

s and
drylands
Drylands are defined by a scarcity of water. Drylands are zones where precipitation
In meteorology
Meteorology is a branch of the atmospheric sciences
Atmospheric science is the study of the Earth's atmosphere
File:Atmosphere gas ...
, in line with obligations under international agreements."
Human uses
Uses of water include
agricultural
Agriculture is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary
Image:Family watching television 1958.jpg, Exercise trends, Increases in sedentary behaviors such as watching tele ...

,
industrial
Industrial may also refer to:
Industry
* Industrial archaeology, the study of the history of the industry
* Industrial engineering, engineering dealing with the optimization of complex industrial processes or systems
* Industrial loan company, a f ...
,
household
A household consists of one or several persons who live in the same dwelling
In law, a dwelling (also residence, abode) is a self-contained unit of accommodation used by one or more households as a home
A home, or domicile, is a s ...

,
recreational
Recreation is an activity of leisure
Leisure has often been defined as a quality of experience or as free time. Free time is time spent away from business, Employment, work, job hunting, Housekeeping, domestic chores, and education, as wel ...
and
environmental
A biophysical environment is a life, biotic and Abiotic component, abiotic surrounding of an organism or population, and consequently includes the factors that have an influence in their survival, development, and evolution. A biophysical environ ...

activities.
Water used for agriculture is called "agricultural water" or
farm water.
Animals
Water is a critical issue for the survival of all living organisms. Some can use salt water but many organisms including the great majority of higher plants and most
mammal
Mammals (from Latin
Latin (, or , ) is a classical language
A classical language is a language
A language is a structured system of communication
Communication (from Latin ''communicare'', meaning "to share" or "to be i ...
s must have access to fresh water to live. Some terrestrial mammals, especially desert
rodent
Rodents (from Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally spoken in the area around Rome, known as Latium. Through the power of the Roman Republi ...

s, appear to survive without drinking, but they do generate water through the
metabolism
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life
Life is a characteristic that distinguishes physical entities
A bubble of exhaled gas in water
In common usage and classical mechanics, a phys ...

of
cereal
A cereal is any Poaceae, grass cultivated (grown) for the edible components of its grain (botanically, a type of fruit called a caryopsis), composed of the endosperm, cereal germ, germ, and bran. The term may also refer to the resulting grain ...

seeds, and they also have mechanisms to conserve water to the maximum degree.
See also
*
*
*
*
*
*
*
*
References
External links
The World Bank's work and publications on water resourcesFresh Water National Geographic
{{Authority control
Aquatic ecology
Hydrology
Water supply