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Termsort ascending Term description

In a religious sense, a thing that both stands for and points to something else and makes that which is being pointed to uniquely present.


The close, often mutually beneficial, association between two or more organisms of different species. The association of algae and fungi in lichens and of bacteria living in the intestines are forms of symbiosis.

sustainable food system

A food system that delivers food security and nutrition for all in such a way that the economic, social and environmental bases to generate food security and nutrition for future generations are not compromised. A food system gathers all the elements (environment, people, inputs, processes, infrastructures, institutions, etc.) and activities that relate to the production, processing, distribution, preparation and consumption of food and the outputs of these activities, including socio-economic and environmental outcomes.

Sustainable Energy for All

The United Nations Sustainable Energy for All initiative has three interlinked objectives to be achieved by 2030: 1. ensure universal access to modern energy services; 2. double the global rate of improvement in energy efficiency; 3. double the share of renewable energy in the global energy mix.

sustainability certification

An official confirmation by a designated, reputable group that certain persons or organizations have the requisite knowledge and follow the accepted practices of environmental sustainability.

surface water

Water on the surface of the earth.

surface runoff

See runoff.

surface flow

The precipitation runoff that travels overland to the stream channel and ultimately into the ocean.


Regions on the solar surface that appear dark because they are cooler than the surrounding photosphere, typically by about 1500 K (thus, they are still at a temperature of about 4500 K, but this is cool compared to the rest of the photosphere). Dark spots, some as large as 50,000 miles in diameter, move across the surface of the sun, contracting and expanding as they go.

Sun Dance

A ceremony practiced by some indigenous people of America and Canada to establish and maintain kinship with all the people's relatives, including other humans, the animal and plant relatives of this earth, and the cosmic relatives of the spirit realm.

summer solstice

The time of year when the sun reaches its highest position in the sky as seen from the North or South pole; longest day of summer sunlight.

sulfuric acid

(H2SO4) An acid produced from sulfur dioxide: used chiefly in the manufacture of fertilizers, chemicals, explosives, dyestuffs, and in petroleum refining.

sulfate anions

A salt or ester of sulfuric acid; a divalent group or anion SO42- characteristic of sulfuric acid and the sulfates.


Below the surface of the Earth; underground.


A surface on which an organism grows or is attached.

subsistence needs

The basic requirements of food, water, shelter and security that a person needs in order to stay alive.

subsistence farming

Farming or a system of farming that provides all or almost all the goods required by the farm family usually without any significant surplus for sale.


The moral principle requiring that community problems be resolved at the appropriate level. Solutions to community problems should not be overly-localized, if the problem requires regional, state, or international assistance; nor should solutions be overly-globalized if the problem can be handled at the state, regional, or community level.


The water flow that occurs in a natural stream or river channel.


The stratosphere extends upward from about 6 to 30 miles. It contains the "good" ozone layer that protects life on Earth from the sun's harmful ultraviolet (UV) rays.

stored carbon sink

A reservoir which stores carbon-containing compounds (fossil fuels; coal, natural gas, oil) for an indefinite period of time. The stored carbon is mainly derived from once active carbon sinks.


The virtue of responsibility for managing, caring for, and improving the natural world. A 'steward' of nature is one who acts in ways that respect the value of nature.


A vast semiarid grass-covered plain, as found in southeast Europe, Siberia, and central North America.


A starch is a carbohydrate that is the chief form of stored energy in plants, especially wheat, corn, rice, and potatoes. Starch is a kind of polysaccharide and forms a white, tasteless powder when purified. It is an important source of nutrition and is also used to make adhesives, paper, and textiles.

St. Ignatius Loyola

A saint of the Roman Catholic Church and founder of the religious order of men known as the Society of Jesus (1491-1556).

St. Ignatius Loyola

A saint of the Roman Catholic Church and founder of the religious order of men known as the Society of Jesus (1491-1556).



A site where water flows to the surface of the earth from underground; where aquifer surface meets the ground surface.


A minute, typically one-celled, reproductive unit capable of giving rise to a new individual without sexual fusion, characteristic of lower plants, fungi, and protozoans.

spirituality of gratitude

In the Christian religious tradition, a way of life characterized by inner commitment and outer actions that acknowledge, in thanksgiving, the giftedness of creation from a loving God.


The inner convictions that give meaning to one's life and expressed in how one acts.

spiritual tradition

Customs or beliefs transmitted from generation to generation about the non-physical strength of a sacred object, process, or being.

Spiritual power

A non-physical strength considered to be expressed in a sacred object, process, or being.

Spiritual experience

An awareness of a non-physical strength considered to be expressed in a sacred object, process, or being.

spiritual exercises

a compilation of meditations, prayers, and contemplative practices developed by St. Ignatius Loyola in the 16th century to help people deepen their relationship with God

specific heat

The amount of heat required to raise the temperature of a unit mass of a given substance by one degree Celsius. Substances with a high specific heat, like water, are characterized by requiring a high amount of heat to warm up, and also by the ability to retain that heat longer than substances with low specific heat.


A population of morphologically and genetically similar organisms that can reproduce sexually among themselves but that cannot produce fertile offspring when mated with organisms belonging to another species.


The formation of new and distinct species in the course of evolution. Speciation involves the splitting of a single evolutionary lineage into two genetically independent ones.


In many religious traditions, the soul is the incorporeal essence of a living thing.


A substance that dissolves other substances, thus forming a solution. Water dissolves more substances than any other, and is known as the "universal solvent".

solar spectrum

The amount of energy emitted by the sun at each different wavelength.

solar radiation

The radiant energy emitted by the sun from the nuclear fusion reaction at the sun's core. The amount of solar radiation that reaches the Earth's surface is impacted by factors like season, time of day, latitude, water vapor, clouds, and pollution.

solar power

Solar power is energy from the sun that is converted into thermal or electrical energy

solar irradiance

Solar irradiance is a measure of solar energy per unit area at a given location. This irradiance varies throughout the year depending on the seasons, time of day, and the cloud cover.

solar energy

The energy contained in the photons received from the sun.

soil type

A member of a soil series distinguished primarily by texture.

soil texture

In a mass of soil, the relative proportion of clay particles to the sand and silt particles.

soil structure

The arrangement of soil into various aggregates, each differing in the characteristics of its particles.

soil profile

A vertical section of soil from the ground surface to the parent rock.

soil particle properties

Include horizonation, soil color, soil texture, soil structure, soil consistence, bulk density, Cation Exchange Capacity, and Soil Reaction (pH)

soil horizon

A layer of soil that can be distinguished from adjacent layers of soil and that is characterized by a certaincolor, texture, structure or chemical composition.

soil formation

The process by which soil is formed as a result of interactions over time between parent material (rock), climate, topography, and organisms.

soil fauna

Animals that inhabit the soil. Soil fauna includes representatives of many groups of terrestrial and aquatic animals.

soil amendments

Materials which are worked into the soil to enhance the soil’s properties. Examples would include organic matter such as compost, manure, bone meal or leaf mold, as well as synthetic fertilizers.

Soil additives

All inorganic and organic substances mixed into the soil for achieving a better soil constitution regarding plant productivity.


The unconsolidated material on the immediate surface of the Earth made of minerals, organic matter, and living organisms that serves as a natural medium for the growth of land plants.


A soft, lightweight, silvery-white metallic element that is the most abundant alkali metal on Earth, occurring especially in common sodium chloride salt. Sodium has many important uses in industry.

Society of Jesus

An order of regular clergy in the Roman Catholic Church, founded by Saint Ignatius of Loyola in 1534, that is strongly committed to education, theological scholarship, and missionary work. Members are called Jesuits.

social system

The political, economic, familial, cultural, and religious structures and processes of a relatively self-sustaining human community in a particular geographic setting.


A quantity of fallen snow that has become massed together.

Slash-and-burn agriculture

A widely used short term method of growing food in which wild or forested land is clear cut and any remaining vegetation burned, resulting in deforestation; loss of habitat and species; an increase in air pollution and the release of carbon into the atmosphere; and an increase in accidental fires; significant soil erosion and accompanying landslides, water contamination, and/or dust clouds.


A large surface crater caused by the collapse of an underground channel or cavern; often triggered by groundwater withdrawal.


The main natural carbon sinks are the oceans and plants and other organisms that use photosynthesis to remove carbon from the atmosphere by incorporating it into biomass. To help mitigate global warming, a variety of means of artificially capturing and storing carbon, as well as of enhancing natural sequestration processes, are being explored.

simple sugars

Simple sugars, or monosaccharide, are sugars that are not decomposable into simpler sugars by hydrolysis.


The deposition of finely divided soil and rock particles upon the bottom of stream and river beds and in reservoirs.


A sediment material of a size between sand and clay whose mineral origin is quartz and feldspar.


A religion founded in the Punjab c1500 by the guru Nanak and noteworthy in its refusal to recognize the Hindu caste system and in forbidding the use of religious statuary and pilgrimages.

short wavelength radiation

Solar energy enters our atmosphere as shortwave radiation in the form of ultraviolet (UV) rays and visible light, which are responsible for sunburn.


A Japanese religion dating from the early 8th century and incorporating the worship of ancestors and nature spirits with a belief in sacred power ( kami) in both animate and inanimate things.

selection pressures

Environmental forces that cause a particular species to evolve in a certain direction that confers an advantage.


The natural process in which material (such as stones and sand) is carried to the bottom of a body of water and forms a solid layer.

sedimentary rock

Rock formed of mechanical, chemical, or organic sediment such as: clastic rock (e.g. conglomerate, sandstone, or shale) formed of fragments of other rock transported from its source and deposited in water; rock (e.g. rock salt or gypsum) formed by precipitation from solution; or rock (e.g. limestone) formed from secretions of organisms.


A ceremonial dinner in the Jewish religion held on the first night or first two nights of Passover that commemorates the Israelites' escape from slavery and the Exodus from Egypt.

secondary consumers

Organisms that feeds on primary consumers in a food chain. They are carnivores (meat-eaters) and omnivores (animals that eat both animals and plants).

Second Law of Thermodynamics

The law of nature which describes the entropy, or measure of disorder, of a system. The entropy of a closed system, as well as the entropy of the universe, must always increase. This is why it is not possible to construct a perfectly efficient machine. Entropy is the gradual decline from an ordered state to a state of disorder.

sea urchins

Sea urchins are invertebrate sea creatures that live in the shallow zones of oceans all over the world and vary in color.  Similar to sea stars, sea urchins have a water vascular system. Their spherical shape is typically small, ranging from about 3 cm to 10 cm in diameter, and their bodies are covered with a spiny shell. The skeleton of a sea urchin is also known as the test. The shells within the test of these creatures are made up of packed, fitted plates which protect them from being damaged.  As for the spines outlining their shell, these are movable and help the sea urchin to camouflage or protect itself from predators.

scientific method

Procedures for the systematic pursuit of knowledge involving the recognition and formulation of a problem, the collection of data through observation and experiment, the formulation and testing of hypotheses, and the analysis of the data to draw a conclusion.


The systematic study of the natural world through observation and experiment.


An organism that feeds on or derives nourishment from decaying organic matter.


A sedimentary rock formed of fine to coarse sand-sized grains that have been either compacted or cemented together. Although sandstone usually consists primarily of quartz, it can also consist of other minerals. Sandstone varies in color from yellow or red to gray or brown.


The accumulation of salts in soil to the extent that plant growth is inhibited. This is a common problem when crops are irrigated in arid regions; much of the water evaporates and salts accumulated in the soil.


A solution containing salt; salty. The concentration of salt in a solution is the solution's salinity. The average salinity of the earth's oceans is 35ppm (parts salt per million parts water).

Sahel region

The semiarid region of western and north-central Africa extending from Senegal eastward to The Sudan. It forms a transitional zone between the arid Sahara (desert) to the north and the belt of humid savannas to the south. It stretches from the Atlantic Ocean eastward through northern Senegal, southern Mauritania, the great bend of the Niger River in Mali, Burkina Faso (formerly Upper Volta), southern Niger, northeastern Nigeria, south-central Chad, and into The Sudan.

Sacred places

Physical locations that are considered to possess a supreme value that cannot be wholly measured by human standards.


The quality of an object that makes it of such a supreme value that it cannot be measured by human standards.

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