Glossary
---------------------------------------------------------------------------------------------- | Aquaculture | The commercial growing of fish, crustaceans and other | | | ocean and freshwater species (e.g. catfish farms). | ---------------------------------------------------------------------------------------------- | Bioaccumulate | The ability of some substances to accumulate along food | | | chains (e.g. from small animals to larger animals to humans | | | or other top predators). | ---------------------------------------------------------------------------------------------- | Bosque | Forest, grove (Span.). In Arizona, mesquite bosques were | | | once common. | ---------------------------------------------------------------------------------------------- | C3 | The most common pathway of carbon fixation in plants. | ---------------------------------------------------------------------------------------------- | C4 | A pathway of carbon fixation, found most commonly in | | | tropical plants that have high rates of growth and | | | photosynthesis and are adapted to high temperatures, | | | strong light, low carbon dioxide levels, and low water supply. | | | because of their affinity for higher levels of carbon dioxide | | | (CO2) C4 tend to grow more rapidly than C3 plants and | | | produce greater yields. In temperate regions, C4 plants may | | | out-compete C3 to become pests. | ---------------------------------------------------------------------------------------------- | Calcareous soil | Soil regarded as alkaline (basic) soil. | ---------------------------------------------------------------------------------------------- | Carcinogenic | Cancer-causing. | ---------------------------------------------------------------------------------------------- | Cienega | Marsh (Span.). | ---------------------------------------------------------------------------------------------- | Crassicaulescent | Crassi (thick) above-ground stems (cactus); a succulent | | | plant. | ---------------------------------------------------------------------------------------------- | Cropland | Land used for the production of adapted crops. In Arizona | | | greater than 95%+ of cropland requires irrigation. | ---------------------------------------------------------------------------------------------- | Cryptogamic | Plants that reproduce by spores or gametes rather than by | | | seeds. | ---------------------------------------------------------------------------------------------- | DDT | Dichlorodiphenyltrichloroethane. An organochloride | | | compound first synthesized in 1874. Its insecticidal | | | properties were discovered in 1939 (by Swiss chemist Paul | | | Hermann Muller who was awarded the Noble prize in | | | Physiology and Medicine for his discovery), DDT was used | | | widely to control anthropod parasites of humans and then as | | | an agricultural and horticultural insecticide. Its use is illegal in | | | the US and many other countries because the chemical | | | stability that allowed it to remain effective for long periods | | | also caused its accumulation along food chains | | | (bioaccumulation) and because target insects were acquiring | | | resistance to it. | ---------------------------------------------------------------------------------------------- | Deciduous | Trees that shed their leaves seasonally. | ---------------------------------------------------------------------------------------------- | Ecosystem | Used to describe a discreet unit that consists of living and | | | non-living parts, interacting to form a stable system. | | | Fundamental concepts include the flow of energy via food- | | | chains and food-webs, and the cycling of nutrients | | | biogeochemically. | ---------------------------------------------------------------------------------------------- | Ecotone | A narrow and fairly sharply defined transition zone between | | | two or more different communities and typically species-rich. | ---------------------------------------------------------------------------------------------- | Edaphic | Relating to factors inherent to soil (salinity, alkilinity, | | | drainage, etc.). | ---------------------------------------------------------------------------------------------- | Endemic | A species or taxonomic group that is restricted to a particular | | | geographic region, owing to such factors as isolation or | | | response to soil or climatic conditions. | ---------------------------------------------------------------------------------------------- | Endomycorrhiza | Mycorrhiza which actually penetrate the cells of plant roots. | | | Found in a wide variety of plant types. | ---------------------------------------------------------------------------------------------- | Ectomycorrhiza | A type of mycorrhiza most common in forest trees covering | | | the root and growing between the root walls, but not | | | penetrating the root itself. | ---------------------------------------------------------------------------------------------- | Facultative | Applied to organisms that are able to adopt an alternative | | | mode of living. (See obligate). | ---------------------------------------------------------------------------------------------- | Headwater | The place of origin of a stream or river. The headwater of the | | | Colorado river is high in the Rocky Mountains. | ---------------------------------------------------------------------------------------------- | Ichthyocides | Chemicals which kill fish. | ---------------------------------------------------------------------------------------------- | Leachate | The solution formed when water percolates through a | | | permeable medium. | ---------------------------------------------------------------------------------------------- | Leaf necrosis | The death of leaves on a plant. | ---------------------------------------------------------------------------------------------- | Littoral | Pertaining to the shore. The area in shallow, fresh water and | | | around lake shores where light penetration extends to the | | | bottom sediments, allowing colonization by plants. | ---------------------------------------------------------------------------------------------- | Macrophyte | Large plant. | ---------------------------------------------------------------------------------------------- | Microphyllous | Plants having small leaves. | ---------------------------------------------------------------------------------------------- | Morphology | The form and structure, as distinct from composition. | ---------------------------------------------------------------------------------------------- | Mutagenic | Causing a mutation in an organism. | ---------------------------------------------------------------------------------------------- | Mutualistic | The interaction between members of two species which | | | benefits both. | ---------------------------------------------------------------------------------------------- | Mycorrhiza | A close physical association between the mycelium of a | | | fungus and the roots of a seed plant, from which both the | | | fungus and the plant appear to benefit. | ---------------------------------------------------------------------------------------------- | Mycrophytic | Small plant. | ---------------------------------------------------------------------------------------------- | NO2 | Nitrogen dioxide. | ---------------------------------------------------------------------------------------------- | NOx | Nitrous oxide. | ---------------------------------------------------------------------------------------------- | O3 | Ozone. | ---------------------------------------------------------------------------------------------- | Obligate | Applied to organisms that are unable to adopt an alternative | | | mode of living, and depend exclusively upon a particular | | | mode. (See facultative) | ---------------------------------------------------------------------------------------------- | Oligotrophic | Applied to lakes that experience little or no mixing of water | | | layers. | ---------------------------------------------------------------------------------------------- | Pasture land | Land used primarily for the production of adapted, | | | introduced or native forage plants for livestock grazing. | ---------------------------------------------------------------------------------------------- | Perturbation | Disturbance, e.g. an earthquake is a geologic perturbation. | ---------------------------------------------------------------------------------------------- | Physiognomic | Apparent, visible characteristics. | ---------------------------------------------------------------------------------------------- | Playa | Beach (Span.). | ---------------------------------------------------------------------------------------------- | PM-10 | Particulate matter smaller than 10 microns in diameter. | ---------------------------------------------------------------------------------------------- | Propagule | Any structure that functions in propagation and dispersal | | | (e.g. a spore or seed). | ---------------------------------------------------------------------------------------------- | Relict | Applied to organisms that have survived while other related | | | ones have become extinct. Often refers to species that | | | formerly had a much wider distribution and have survived | | | locally. | ---------------------------------------------------------------------------------------------- | Resilience | The ability of a system to recover following a perturbation or | | | disturbance. | ---------------------------------------------------------------------------------------------- | Resistance | The capacity of a system to withstand or survive stress and/ | | | or disturbance. | ---------------------------------------------------------------------------------------------- | Restorability | The extent to which a system can be restored to its original | | | functionality. | ---------------------------------------------------------------------------------------------- | SO2 | Sulfur dioxide | ---------------------------------------------------------------------------------------------- | Symbiont | A symbiotic organism. | ---------------------------------------------------------------------------------------------- | Symbiosis | A general term describing the situation in which dissimilar | | | organisms live together in close association. | ---------------------------------------------------------------------------------------------- | Tailings | Fine waste material from a mineral processing plant, which is | | | too poor for further processing. | ---------------------------------------------------------------------------------------------- | Taxon (pl. taxa) | A group of organisms of any taxonomic rank (e.g. family, | | | genus or species). | ---------------------------------------------------------------------------------------------- | Trophic level | A step in the transfer of food or energy within a chain. There | | | may be several trophic levels within a system, for example, | | | producers (plants), primary consumers (herbivores-cows), | | | and secondary consumers (carnivores-lion); further | | | carnivores may form fourth and fifth levels. There are rarely | | | more than five levels since usually by this stage, the amount | | | of food or energy is greatly reduced. | ---------------------------------------------------------------------------------------------- | Turbid | Muddy or cloudy from having the sediment stirred up. | ---------------------------------------------------------------------------------------------- | Xerophyte | A plant that can grow in very dry conditions and is able to | | | withstand periods of drought. | ----------------------------------------------------------------------------------------------