Lexicon: Key Words to Know in Describing Our Environment

Check your vocabulary! Here are words you are likely to encounter as you begin your journey to study environmental science. 

Albedo Effect

Albedo is an expression of the ability of surfaces to reflect sunlight (heat from the sun). Light-colored surfaces return a large part of the sunrays back to the atmosphere (high albedo). Dark surfaces absorb the rays from the sun (low albedo). Ice- and snow-covered areas have high albedo, and an ice-covered Arctic reflects solar radiation which otherwise would be absorbed by the oceans and cause the Earth’s surface to heat up. The proportion of the Earth’s surface that is covered by snow and ice has a great deal to say for how much of the incoming solar radiation is reflected or absorbed. Low albedo (dark surfaces) leads to higher uptake of energy and, hence, warming.

Anoxic

Anoxic describes a condition in which the aquatic environment does not contain dissolved oxygen (DO), which is called an oxygen-deficient condition. Generally, it refers to an environment in which chemically bound oxygen, such as in nitrate, is present.

Archaea

A domain of single-celled organisms. These microorganisms lack cell nuclei and are therefore prokaryotes. Archaeal cells have unique properties separating them from the other two domains, Bacteria and Eukaryota.

Benthon (or Benthos)

Community of organisms that live on, in, or near the bottom of a sea, river, lake, or stream, also known as the benthic zone.

Bioelectrogenesis

The process by which organisms produce electricity, the most commonly known being the electric eel. The process can occur through a variety of means, including: 

  • Cellular metabolism: The breakdown of carbon through fermentation and decomposition in yeast, for example, can produce electricity. 

  • Photosynthesis: A process that generates electricity. 

  • Nervous impulses: A process that generates electricity. 

Bioelectrogenesis can also occur through microbial fuel cells (MFCs), which are bio-electrochemical systems that convert chemical energy into electricity. In an MFC, microorganisms respire and catalyze the conversion of chemical bonds in organic compounds into electrical energy.

Biofouling

Biofouling, or biological fouling, is the accumulation of microorganisms, plants, algae, or small animals on wet surfaces that have a mechanical function, causing structural or other functional deficiencies. There are two phases or types of biofouling: microfouling and macrofouling. Biofouling is common on floating buoys and is a well known problem for the marine shipping industry as well as oceanographers relying on floating, long-term devices deployed at sea to gather scientific data and observations.

Biomes

Source: wikipedia.org

Biomes are large ecosystems with characteristic vegetation and associated animals. Moisture and temperature are the key variables that determine what type of biome is created, such as forest, grassland or desert. Altitude and latitude also influence biomes because they affect moisture and temperature. 

Biota

Biota represents the animal and plant life of a particular region, habitat, or geological period.

Biotic and Abiotic

Biotic means living things, various levels of organisms; Abiotic refers to rocks, soil, and water. For example, the difference between a community in the environmental sense and an ecosystem is that the community is a set of various species, whereas an ecosystem is various species plus their abiotic surroundings.

Similarly, the biosphere means all creatures on earth, whereas the ecosphere is the biosphere plus abiotic surroundings. All ecosystems form our ecosphere.

Cenozoic

The Cenozoic is Earth's current geological era, representing the last 66 million years of Earth's history. It is characterised by the dominance of mammals, birds, and angiosperms (flowering plants).

Cryosphere

The cryosphere is the part of the Earth's climate system that includes solid precipitation, snow, sea ice, lake and river ice, icebergs, glaciers and ice caps, ice sheets, ice shelves, permafrost, and seasonally frozen ground.

Demersal

Living close to the floor of the sea or a lake. For example, demersal fish. Also known as groundfish, live and feed on or near the bottom of seas or lakes (the demersal zone).

Ectotherms, or Poikilotherms

Ectotherms are animals that do not regulate their body temperature. Their temperature is derived exclusively from their external environment.

Eocene

The Eocene epoch is part of the Tertiary Period in the Cenozoic Era, and lasted from about 54.8 to 33.7 million years ago. The oldest known fossils of most of the modern orders of mammals appear in a brief period during the Early Eocene and all were small, under 10 kg (~22 lbs.).

Detritivore

These are animals that feed on dead organic material, especially plant detritus. Examples include termites, snails, earthworms, millipedes, and fungi.

Ectotherms, or Poikilotherms

Ectotherms are animals that do not regulate their body temperature. Their temperature is derived exclusively from their external environment.

Entropy

Entropy is a thermodynamic quantity representing the unavailability of a system's thermal energy for conversion into mechanical work, often interpreted as the degree of disorder or randomness in the system. Entropy is central to the second law of thermodynamics, which states that the entropy of an isolated system left to spontaneous evolution cannot decrease with time. As a result, isolated systems evolve toward thermodynamic equilibrium, where the entropy is highest. A consequence of the second law of thermodynamics is that certain processes are irreversible.

Fens

A type of wetland, in the same category as a bog, a swamp, or a marsh: an in between type of environment between aquatic and terrestrial. Fens are like wet meadows with sedges instead of grass. Fens are peat-forming and rely on groundwater input, requiring thousands of years to develop, and cannot easily be restored once destroyed. Fens are also hotspots of biodiversity. They often are home to rare plants, insects, and small mammals.

Geophony

From the Greek prefix, geo, meaning earth-related, and phon, meaning sound, is a neologism used to describe one of three possible sonic components of a soundscape. It relates to the naturally occurring non-biological sounds coming from different types of habitats, whether marine or terrestrial. Typically, geophony refers to the sounds of natural forces, such as water, wind, and thunder, occurring in wild, relatively undisturbed habitats.

Homeotherms

Homeotherms are animals that can regulate their temperature. Therefore, they can withstand greater variations in environmental temperature.

Ichthyology

Ichthyology is the branch of zoology devoted to the study of fish, including bony fish, cartilaginous fish, and jawless fish. According to FishBase, the global encyclopedia about fish, 33,400 species of fish had been described as of October 2016, with approximately 250 new species described each year.

Niche

While most people understand this world in general, in environmental science and zoology in particular, it means a role that an animal plays in the ecosystem; for example, wolves are large terrestrial pack-hunting predators. Used in conjunction with habitat, which is the place an animal lives, or spends most of its life.

Nekton

Living organisms that are able to swim and move independently of currents. Nekton are heterotrophic and have a large size range, with familiar examples such as fish, squid, octopus, sharks, and marine mammals.

Neuston (or Pleuston)

Organisms that live at the surface of a body of water, such as an ocean, estuary, lake, river, or pond. Why is it relevant? Great efforts are underway cleaning up the ocean, but some complain, saying “Yeah, but they pick up a lot of neuston!”

pH Level

The pH level is a core environmental factor, in addition to temperature, salinity, light, dissolved oxygen, and nutrients. It is a quantitative measure of the acidity or basicity of aqueous or other liquid solutions. The term translates the values of the concentration of the hydrogen ion—which ordinarily ranges between about 1 and 10−14 grams-equivalent per liter—into numbers between 0 and 14. In pure water, which is neutral (neither acidic nor alkaline), the concentration of the hydrogen ion is 10−7 grams-equivalent per liter, which corresponds to a pH of 7. A solution with a pH less than 7 is considered acidic; a solution with a pH greater than 7 is considered basic, or alkaline[1]

Pelagic

The pelagic zone consists of the water column of the open ocean. Pelagic fish, live and feed away from the bottom in the open water column - in contrast to demersal fish.

Permafrost

Permafrost is any ground that remains completely frozen—32°F (0°C) or colder—for at least two years straight. These permanently frozen grounds are most common in regions with high mountains and in Earth's higher latitudes—near the North and South Poles. As of 2023, permafrost covers large regions of the Earth.

Plankton

The word “plankton” comes from the Greek for “drifter” or “wanderer.” An organism is considered plankton if it is carried by tides and currents, and cannot swim well enough to move against these forces. They live sufficiently close to the surface of the water to access sun light and generate oxygen through photosynthesis.

Tomium

The cutting edge of the bill of a bird (from New Latin, from Greek tomos cutting, sharp + New Latin -ium).

Sources:

  • www.wikipedia.org

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