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close this bookBiological Monitoring: Signals from the Environment (GTZ, 1991)
View the document(introduction...)
View the documentAcknowledgements
View the documentForeword
View the documentIntroduction
close this folderBioindicators and Biological Monitoring
View the document(introduction...)
View the document1. Abstract
View the document2. The situation
View the document3. The problem
close this folder4. Definitions
View the document(introduction...)
View the document4.1 Relationship between the ''environment'' and ''indicators''
View the document4.2 Qualitative and quantitative biological monitoring
View the document4.3 Bioindicator types
View the document4.4 ''Levels'' of biological monitoring
close this folder5. Examples
View the document5.1 The landscape and biome levels
View the document5.2 The ecosystem and biocenosis levels
View the document5.3 The levels of populations and individuals
View the document5.4 Potential for use of biological monitoring techniques in developing countries
View the document6. Conclusions
View the documentReferences
close this folderConcept for a biological monitoring study:
View the document(introduction...)
close this folder1. The nature of the problem and background information
View the document1.1 The conflict between mining and agriculture on the Andean plateau
View the document1.2 Scope of the case study concept
View the document1.3 Major criteria for biomonitoring of pollution caused by mining and metallurgical operations
close this folder2. Study area: the central Andean plateau
View the document2.1 Location and extension
View the document2.2 Natural features
View the document2.3 Population
View the document2.4 Agriculture
View the document2.5 Mining and industry
View the document2.6 Special aspects of environmental contaminants, their effects on living organisms and ecosystems, and their detection by means of bioindicators on the Andean plateau
close this folder3. Study approaches
View the document3.1 Studies of the range of distribution and relative intensities of current environmental contaminatron emanating from a source
View the document3.2 Studies of the regional history of contamination by means of peat profiles
View the document3.3 Studies of the long-term effect of contamination on the agriculturally utilized ecosystems of the Andean plateau
View the document3.4 Time frame of study programs
View the document3.5 Required scientific and technical infrastructure in the field and in the country where studies are being performed
View the document4. Summary
View the documentReferences
close this folderBioindicators and biomonitors in aquatic ecosystems with special attention to potential applications in developing countries
View the document(introduction...)
View the document0. Abstract
View the document1. The context
close this folder2. Means of detecting water pollution
View the document(introduction...)
View the document2.1 General review of assessment procedures and definitions
close this folder3. Biological assessment
View the document(introduction...)
View the document3.1 Saprobic systems: evaluative techniques involving indicator organisms and related methods
View the document3.2 Evaluation of water quality with the aid of biomonitors
View the document4. Water evaluation by remote sensing
View the document5. Summary: Use of bioindicators and biomonitors in developing countries
View the documentReferences
close this folderThe Use of Bioindicators for Environmental Monitoring in Tropical and Subtropical Countries
View the document(introduction...)
View the document1. Introduction
View the document2. Definitions and basic principles of biological monitoring
close this folder3. Bioindicators in tropical and subtropical countries
View the document(introduction...)
View the document3.1 Pointer species and pointer communities
View the document3.2 Response indicators
View the document3.3 Accumulative indicators
View the document4. Discussion and recommendations
View the document5. Summary
View the documentReferences
close this folderBioindicators for monitoring of atmospheric pollutants in Asian countries
View the document(introduction...)
View the document1. Introduction
close this folder2. Applied biological monitoring techniques in Asia, with special consideration given-to the developing countries
View the document2.1 Fumigation and dusting experiments as the basis for selection of biological indicators
View the document2.2 Active monitoring
View the document2.3 Passive monitoring
close this folder3. Summary in table form of the surveyed publications
View the document(introduction...)
View the document3.1 India
View the document3.2 China
View the document3.3 Hong Kong
View the document3.4 Other countries
View the document4. Conclusions
View the documentReferences
View the documentChemical Substances and Compounds
View the documentGlossary

Glossary

Acrocarpous

In some mosses of the subclass Eubrya, having the sporophyte at the end of the stem, thus exhibiting an erect habit.

Active monitoring

Cf. text by Ellenberg - Fig. 4.

Aerial

Relating to or occurring in the air or above the ground.

Alkaline collector traps

Artificial surfaces coated with an alkaline medium to absorb acidic atmospheric components.

Allochthonous nutrients

Nutrients that are transported from elsewhere into an ecosystem.

Allochthonous organic matter

Organic matter of external origin, such as fallen leaves in a brook.

Andesite

An extrusive, usually dark greyish, rock consisting essentially of plagioclase feldspar with dark ferromagnesian minerals and little or no quartz.

Angiosperms

The common name for members of the plant division Magnoliophyta.

Anion

A negatively charged atom or group of atoms, or a radical that moves towards the positive pole (anode) during electrolysis.

Aquatic system

Cf. text by Bretthauer.

Arthropods

Members of the large phylum of the Arthropoda, comprising invertebrate animals with jointed legs and a segmented body; e.g. insects, spiders and myriapods.

Assimilation

The incorporation or conversion of nutrients into protoplasm that in animals follows digestion and absorption, and in higher plants involves both photosynthesis and root absorption.

Assimilation organs

(Mainly) leaves.

Atomic absorption spectroscopy

AAS - physical method of determining heavy metal contents.

Autotrophic soil algae

Self-nourishing green algae living in soil (capable of synthesizing organic nutrients directly from simple inorganic substances).

Azonal soils

Soils that have developed under special conditions not typical of the surrounding area, mostly influenced by the action of wind and water (e.g. the soils of valley bottoms and sand dunes).

Background contamination

The natural heavy metal content in the stones and soils of an area that is being investigated to determine pollution of it with the same metals.

Bar diagram

Block diagram depicting data from measurements.

Binoculars

An optical instrument with two eyepieces.

Biochemical oxygen demand (BOD)

The quantity of oxygen that organisms need to mineralize degradable organic matter, especially in the breakdown of organic matter by microorganisms in a water body.

Biocoenosis

A community of biologically integrated and in terdependent plants and animals.

Biodegraded

Organic compounds that have been broken down by microorganisms.

Biological indication

Cf. text by Ellenberg.

Biomass

The amount of living matter (expressed per unit area or volume of habitat).

Biome

A complex biotic community covering a large geographic area and characterized by the distinctive life forms of important climax species.


Examples: tundra, taiga, tropical rain forest.

Biomonitoring

Cf. text by Ellenberg - Fig. 4.

Biota

All of the living organisms of a given region, including flora, fauna and microorganisms.

Biotope

A habitat that is uniform in its principal climatic, soil and biotic conditions (e.g. a sandy desert).

BOD

Biochemical oxygen demand (cf. above).

C/N ratio

The quantitative relation between carbon and nitrogen.

Calcination

The process of heating an organic material to a high temperature (but without fusing it) in order to drive out volatiles or affect it in some other way (e.g. oxidation or pulverization).

Canopy roughness

The unevenness or vertical geometric variations in the upper surface of a plant stand (e.g. a forest).

Carbon-14dating

A technique in which a radioactive isotope of carbon (carbon-14) is employed as a tracer in chemical and biochemical research. Because this isotope is present in all carbon-containing matter, it is useful for dating archaeological specimens, fossils, etc.

Carotenoid content

Cf. text by Arndt.

Carotenoids

Pigments that occur in plants and some animal tissues; they include carotene, xanthophylls and other fat-soluble pigments.

Catalase

An enzyme that occurs in plant and animal tissues; it decomposes hydrogen peroxide into water and oxygen.

Cations

A positively charged atom or group of atoms, or a radical that moves to the negative pole (cathode) during electrolysis.

Checkerboard pattern

A regular pattern of squares like that of a checkerboard.

Chironomids

Insects belonging to the family of slender, long winged, long-legged, small and very delicate nemotoceran Diptera, commonly called midges or true midges. They are scavengers, not blood suckers.

Chloroplasts

A type of cell plastic occurring in the green parts of plants; they contain chlorophyll pig ments and play a role in photosynthesis and protein synthesis.

Chlorosis

An abnormal condition in plants characterized by the absence of green pigments; it can becaused by lack of light or a deficiency of iron or magnesium. (Cf. text by Arndt).

Chlorotic injury

A disease condition of green plants, manifesting itself as yellowing of the green parts of a plant.

Cilicate

A single-celled animal with cilia on its surface.

Combined exposure

Exposure to different toxins in combination.

Compacted soils

Soils with few openings through which exchange of gases or percolation of water can take place.

Composite

A plant of the large Compositae family of dictyledonous plants with flower heads composed of dense clusters of small flowers surrounded by a ring of small leaves or bracts; the daisy, thistle, artichoke, chrysanthemum, etc. belong to this family.

Cumulative biological indicators

Cf. footnote to text by Ellenberg - p. 18, Fig. 4.

Coupling analysis

A special method for determining saprobity levels by using only a small number of very characteristic indicator species; only employed in Baden-Wuerttemberg (Federal Republic of Germany).

Cushion plants

Plants with globular or regularly rounded surfaces adapted to minimize water losses from transpiration, typical of high mountainous areas affected by frequent, strong winds.

Cumulative bioindicators

Cf. texts by Ellenberg and Steubing.

Cystolith

A concretion of calcium carbonate arising from the cell walls of modified epidermal cells in some flowering plants.

Defoliation

The loss of leaves in plants caused by a toxin or some other external effect.

Degradability

The decomposability of organic matter by the metabolic processes of animals or plants in the soil.

Diatoms

Unicellular algae; common name of the bacilla riophyta. Some are colonial, green or brownish in color (but all contain chlorophyll), with siliceous and often highly sculptured cell walls. They make up much of the producer level in marine and freshwater food chains, and they have contributed to the formation of oil reserves.

Dicotyls

Plants belonging to the plant class Dicotylae, all having two cotyledons, i.e. two leaves at the very early stage of life, as opposed to monocotyls.

Diffusion resistance

Stomatal resistance to exchange of gases and vapours.

Dioecious

Of plants, having the staminate and pistillate (male and female) flowers on separate individuals.

Disease vector

An animal, such as an insect, that transmits a disease-producing organism from one host to another.

Dissilimation

The disintegration of protoplasm, principally by oxidation.

Ecochemicalcomposition

The chemical composition of the surrounding environment.

Ecologicalvalence

The ranges of biological and abiotic factors within which an organism is able to live.

Ecosystem

A system made up of a community of plants, microorganisms and animals, along with their physical and chemical environment.

Ecotoxicologist

A specialist who works to determine the impacts of pollutants on the environment.

Ecotype

A biotype or a characteristic population of a species of organism resulting from natural selection in a given habitat.

Electrophoresis

An electrochemical process in which colloidal particles or macromolecules with a net electric charge migrate in a solution under the influence of an electric current; also known as cataphoresis.

Endemic

Confined to a given region and having originated there.

Enrichment horizons

Soil horizons in which salts such as lime, gypsum or clay accumulate.

Environmental impact inventory

A survey of the influence of polluting substances on the environment.

Environmental specimen

An animal or plant taken as a sample from an ecosystem for analysis. Within the scope of biological monitoring, the sample is designed so as to be representative of that ecosystem.

Epicuticular wax

The superficial layer of wax that covers leaves.

Epilothic

Of plants, growing on the surfaces of rocks and stones, e.g. algae and lichens.

Epiphyte

A plant that grows nonparasitically on another plant, deriving moisture and nutrients from the air. Also known as aerophyte. Cf. text by Steubing.

Euryhaline species

Organisms that are capable of tolerating a wide range of saline conditions.

Euryoecic

Not narrowly limited by ecological conditions. The opposite condition, when organisms are only able to live within a narrow range of ecological conditions, is called "stenoecic", e.g. a plant that does not tolerate any shade, or a trout that requires oxygen-rich water.

Eutrophication

The process by which a body of water or a terrestrial ecosystem becomes rich in plant nutrients; in this volume, reference is principally made to nitrogen and phosphorus.

Evapotranspiration

The combined evaporation of water from the soil surface and transpiration from plants.

Exposure experiments

Experiments in which organisms are exposed to certain environmental conditions, especially pollutants.

Eyrie

The nest of an eagle or other large bird of prey.

Filiform bacteria

Threadlike bacteria.

Flotation processes

The separation of the constituent particles of a mass of pulverized ore by taking advantage of their differing ability to float on a given liquid.

Foliar

Referring to leaves.

Gastropods

A large, morphologically diverse class of the phylum Mollusca, containing the snails, slugs, limpets, and conchs.

Genus (pi. genera)

A class, kind or group of organisms marked by common characteristics or by one common characteristic, specifically: a category of biol ogical classification ranking between the family and the species, comprising structurally or phylogenetically related species or an isolated species exhibiting unusual differentiation, and designated by a Latin or latinized capitalized singular noun.

Germinative capacity

The capacity to reproduce.

Gonads

Organs that produce reproductive cells, especially an ovary or testis.

Gymnosperms

The common name of members of the division Piniphyta; seed-bearing plants having naked ovules at the time of pollination. Example: pine trees.

Halobiontic

Living in water or on the bottom of a saline water body.

Halophilic

Salt-loving; thriving under saline conditions.

Halophobic

Thriving only in extremely salt-poor water; also called haloxenic.

Halophytic

Refers to shore plants capable of thriving on salt-impregnated soils.

Halophytic plant communities

Communities of plants growing on salty soils.

Hard cushion bogs

Marches or mires consisting of hard, solid cushion plants (cf. above).

Herbivorous

Feeding on plants; plant-eating.

Heterophyllous

Having more than one form of leaves on the same plant or stem.

Heterotrophic

Deriving nourishment from organic substances, e.g. parasitic plants and all animals; antonym: autotrophic.

Heterotrophic soil algae

Organisms that nourish themselves by ingesting and breaking down organic matter (these algae are not green).

Hygrophilous

Living or growing in places with moist air, in many cases on moist or wet soils.

Hymenopters

Bees, wasps and the like.

Hypertrophication

A situation in which considerably more plant nutrients are available in an ecosystem than are needed, thus leading to problems.

Idioblast

A plant cell that differs markedly in shape or function from neighboring cells within the same tissue.

In-site production

Production in position, in its original place; autochthonous production, like algae growing in a brook.

Intercostal zone

The zone between the veins or nerves of a leaf.

Ion-selective electrode

A physicochemical method of measuring ion concentrations.

Isoenzyme

Any of the electrophoretically distinct forms of an enzyme, representing different polymeric states but having the same function. Also known as isozyme.

Katabatic winds

Cold winds that drop down from high mountains to warmer valleys during the night. Also known as gravity winds.

Large-lobed foliose lichens

Lichens with large, leaf-like lobes.

Leaf necrosis

Localized death of living tissue in leaves.

Leghemoglobin

Red pigment involved in symbiotic fixation of nitrogen from the air by legumes.

Lichen thalli

A group of organisms consisting of fungi and algae growing together symbiotically.

Limnic water

Fresh water in a lake.

Limnology

The study of the physical, chemical and biological components of fresh water.

Littoral zone

The part of a lake extending from the shore down to the limit for rooted vegetation.

Liverworts

The common name for members of the Hepaticae; small plants, mostly terrestrial, attached to the substrate by rhizoids. Related to hornworts and mosses.

Lotic water

Flowing water, i.e. rivers and streams. Antonym: lentic = standing.

Macchia

A characteristic type of Mediterranean brush or scrub landscape, the result of centuries of fires and grazing by sheep and goats.

Macrophytes

Large aquatic plants, as opposed to phytoplankton and other small algae.

Marchantiales

The thalloid liverworts, an order of the class of the Marchantiopsida, having a flat body composed of several distinct tissue layers, smoother walled and tuberculate-walled rhizoids, and male and female sex organs borne on stalks on separate plants.

Metabolic changes

Chemical changes; the sum of the processes by which a given substance is dealt with in an organism.

Metabolite

A product of metabolism or a substance essential to the metabolism of a given organism or metabolic process.

Metabolization

The chemical and physical processes continuously going on in living organisms and cells, comprising those by which assimilated food is built up into protoplasm and those by which organic compounds are used and broken down into simpler substances and waste, with release of energy for all vital purposes.

Metamorphic rocks

Rocks produced by metamorphism (a change in the constitution of rock, especially a pronounced change effected by pressure, heat and water that results in a more compact and more highly crystalline condition). Example: Gneiss.

Mitochondria

Membrane-bounded particles that are present in the cytoplasm of all eukaryotic cells. Mitochondria contain enzyme systems which are responsible for providing energy in the form of ATP.

Mobilization

Enhancement of mobility.

Molybdates

Salts of molybdenum containing the group MoO4 or MoO2.

Monocotyledons

All plants of the class Liliopsida; they have a single cotyledon (the first leaf of the embryo of seed-bearing plants).

Mormyridae

A fish family, including the so-called Nile perch.

Moss bag test

Cf. texts by Steubing and Arndt.

Multiple layer palisade

Refers to leaves that have several parenchymal layers of densely packed cells containing many chloroplasts.

Mycorrhizae

Symbiotic associations of the roots of higher plants with a fungus. Singular: Mycorrhiza.

Net primary production (NPP)

The net product of photosynthetic assimilation by a green plant, minus immediate metabolic needs (in energy terms).

Nitrogen cycle

Nitrogen metabolism, atmospheric nitrogen fixation, assimilation of nitrogen into proteins and other organic compounds, and the reverse processes.

Nodules

Small knoblike structures (e.g. the nodules of grass blades).

Non-homoiothermal terrestrial

Any animal except mammals and birds. The in

vertebrates

tensity of life and activity of these animals de pends on climatic temperature conditions.

Nuclide

A species of atom characterized by the number of protons, number of neutrons, and energy content in the nucleus, or alternatively by the atomic number, mass number, and atomic mass.

Nutrient leaching

The removal of plant-available nutrients from the soil by being washed out by water.

Orache

Any of a genus of plants of the goosefoot family, widespread in salty and alkaline areas, usually having silvery foliage and small green flowers.

Orographic

Penaining to relief factors such as hills, mountains, plateaus, valleys and slopes; describing the surface of the earth.

Osmotic pressure

The applied pressure required to prevent the flow of a solvent across a membrane which of fers no obstruction to passage of the solvent, but does not allow passage of the solute, and which separates a solution from the pure solvent.

Overlapping accumulation periods

Overlapping time spans for the accumulation of toxins in plants.

Oxidophilic organisms

Organisms that live in oxygen-rich waters.

Paleozoic schists

Schists that originated in the era of geological history extending from the beginning of the Cambrian to the close of the Permian.

Parasitism

An association of two kinds of organism in which the parasite is benefited and the host is usually harmed.

Passive monitoring

Cf. text by Ellenberg - Fig. 4.

Peat horizon

Peat layer.

Pedological

Related to the soil with its living organisms, and including its water, nutrient and other physical components.

Pentacyclic triterpenes

Squalenoids; a group of organic compounds with 5 carbon rings, cf. Iist of chemicals.

Perchloric acid

Cf. Iist of chemicals.

Perioxidase

An enzyme that catalyzes reactions in which hydrogen peroxide is an electron acceptor.

Periphyton

"Aufwuchs"; the organisms attached to under water rooted plants.

Persistent halogenated hydrocarbons

Toxic compounds that are nearly impossible to metabolize, etc. DDT and PCBs.

Phenology

The study of natural phenomena that recur periodically.

Phosphatase activity

The (chemical) activity of enzymes found in body tissues and fluids, that hydrolyze phosphoric acid esters of organic compounds, liberating phosphate ions.

Photochemical oxidant

Any of the chemicals that enter into oxidation reactions in the presence of light or other radiant energy, particularly ultraviolet light.

Photochemical smog

Chemical pollutants in the atmosphere resulting from chemical reactions involving hydrocarbons and nitrogen oxides in the presence of sunlight.

Physicochemical measurement

Measurement of both purely physical and chemical properties, changes and reactions as opposed to the biological monitoring approach.

Phytomonitoring methods

Methods by which the amount and impact of pollution can be evaluated using plants as indicator organisms.

Phytosociological survey

Cf. text by Steubing.

Phytotoxicity

Poisonousness to plants.

Plant tissue

An aggregation of cells more or less similar morphologically and functionally.

Plantaginacae

The family including plantain and ribgrass.

Pleurocarpous

Having the sporophyte in leaf axils along the side of the stem or on lateral branches; refers specifically to mosses.

Pollen germination test

Cf. text by Amdt.

Pollen grain germination

Germination of the haploid microspore of seed bearing plants.

Pollen tube growth

Growth of the pollen tube; a tubular process developed from pollen grain after attachment to stigma, and growing towards the ovule carrying male nuclei to an embryo sac.

Pollution gradients

The rate of regular or graded ascent or descent of pollution.

Pollution response inventory

A survey of bioindication methods or biological measurement approaches.

Polycyclic aromatic hydrocarbons

Organic compounds consisting of two or more hydrocarbon rings; included in many insecticides. Cf. list of chemicals.

Population turnover

The exchange of older organisms (after their death) for younger ones, from the point of view of population dynamics.

Porometrics

Measurement methods for determining stomata! aperture and CO2/H2O gas exchange.

ppm

Parts per million

Predation

The ecological relationship between food organisms and the organisms that feed on them, if the food is still alive when taken. Typical predators are lions, wolves and goshawks; strictly speaking, however, herbivores are also predators.

Primary producers

Green plants.

Protista

A proposed kingdom to include all unicellular organisms lacking a definite cellular arrangement, such as bacteria, algae, diatoms, and fungi.

Protozoa

A diverse phylum of eukaryotic microorganisms; the structure varies from a simple uninucleate protoplast to colonial forms.

Radionuclide

A nuclide that exhibits radioactivity.

Regression analysis

A comparative method for identifying the gradual loss of differentiation and function in an organism; a functional relationship among two or more correlated variables that is often empirically determined from data and used above all to predict values of one variable when the values of the others are known.

Relative standard deviation

Variance.

Remote sensing

The gathering and recording of information without actual contact with the object or area being investigated.

Respiration rate

The rate at which tissues and organisms take up oxygen from their environments and produce carbondioxide.

Rhizome grasses

Grasses with an underground horizontal stem, often thickened and tuber-shaped and possessing buds, nodes and scale-like leaves.

Ribosome

One of the small, complex particles composed of various proteins and three molecules of ribonucleic acid which synthesize proteins within the living cell.

Roast

To heat ore to effect some chemical change that will facilitate smelting.

Root zone

The layer of soil within which plant roots occur.

RPC system

The "reducer-producer-consumer" system, a relatively unsuited method for determining water quality.

Salt electrolysis

Induction of chemical changes by passing an electric current through an electrolyte (a non metallic electric conductor in which current is carried by the motion of ions), in this case salt.

Sapropel

Sediment consisting of dead aquatic organisms, principally occurring in eutrophic waters where anaerobic bacteria decompose organic matter by biochemical means.

Saprophyte

A plant that lives on decaying organic matter.

Schist

A large group of coarse-grained metamorphic rocks which readily split into thin plates or slabs as a result of the alignment of lamellar or prismatic minerals.

Sclerophyllous

Characterized by thick, hard foliage.

Secondary atmospheric pollutants

For instance: ozone, which only emerges under certain climatic and chemical conditions.

Sensitive bioindicators

Cf. text by Ellenberg - Fig. 4.

Sessile ciliates

Ciliates attached to the substrate. Antonym: free-swimming.

Sessile organisms

Organisms attached to the substrate, for instance the common marine mussel Mytilus edulis.

Sheet erosion

Movement of upper soil layers on minimally in clined surfaces, induced by the action of running water.

Siliceous magma

Magma containing silica or silicates.

Soil water capacity

The capacity of the soil to retain water against the pull of gravity.

Species

A taxonomic category ranking immediately below a genus and including closely related, morphologically similar individuals which actually or potentially interbreed.

Specimen tissue

Tissue sampled from an organism ("specimen") that is thought to be representative of the organism or a population or organisms - used here in the context of chemical residue analysis with biological monitors.

Stenobiontic

Said of organisms which only tolerate changes in their environmental conditions within certain narrow limits.

Steranes

Modern name: gonanes; a special class of steroids without angular methyl groups at the 10th and 13th carbon atoms.

Stoma (pi. stomata)

A small opening or pore in a surface, especially one of the minute openings in the epidermis of higher plants which are regulated by guard cells and through which gases and water vapor are exchanged between internal spaces and the external atmosphere.

Stomatal density

The number of stomata per unit area.

Stomatal response

The opening width of stomata is regulated by both internal factors (e.g. internal CO2 concen tration and water vapor pressure) and indirectly by external (environmental) factors.

Subarid climate

A climate with a very pronounced dry season of considerable duration and only a few months of scant rainfall.

Subhumid climate

A climate in which a dry season is clearly present but not pronounced.

Sublethal

Insufficient to cause death, not quite lethal (= causing death, deadly), at least for most of the organisms under observation.

Substrate

The base on which an organism lives, e.g. the soil or a part of another plant (in the case of epiphytes); a substance that is acted upon (e.g. by an enzyme).

Succulent

A plant with juicy, fleshy tissues adapted to conserve water, covered by a surface that minimizes evapotranspiration.

Synecological information

Information about the structure, development and distribution of ecological communities.

Terrestrial ecosystem

Cf. text by Ellenberg.

Thalassogenic

Said of waters that are influenced by marine water.

Thallic tissue

Cf. thallus.

Thallus

A plant tissue or body that is not differentiated into specialized tissue systems or organs such as leaves or stems; it may vary from a single cell to a complex, branching multicellular structure.

Thermal stratification

Tabular strata in standing water (for instance, in most Central European lakes during the summer: warm surface water, medium-temperature boundary layer, cool bottom water), caused by the distinct specific densities of water of differ ent temperatures.

Thermohygrograph

An instrument for measuring and recording variations in atmospheric humidity and temperature.

Third primary quill

The third large feather of the wing of a (large) bird, counting from the body side towards the wing tip.

Toxin

A poisonous substance, poison.

Transpiration resistance

Resistance to diffusion of water vapor.

Transplanted specimens

Organisms, normally plants, taken from a given stand - naturally grown or artificially raised - and planted or exposed at another place. They are taken for experimental purposes as being 1. an item representative of others in the same class or group, and/or 2. a sample selected for testing, examination, or display.

Trichome

An appendage occurring on the cuticles of plants, such as hairs and scales.

Trifoliate

Of leaves, consisting of three leaflets.

Trophic level

Herbivore, carnivore, parasite, saprovore, etc. Herbivores belong to the "first" trophic level, while predators that feed upon herbivores be long to the "second". Predators that normally feed on other predators are situated on the "third" or even higher levels, e.g. sparrow hawks when feeding on insectivorous birds.

Trophic relationships

Feeding relationships; of or relating to nutrition. Trophic relationships constitute one of the principal relationships among organisms of different species in an ecosystem.

Trypanosome

Any of a genus of flagellate protozoans that live as parasites in the blood of human beings and other vertebrates. They are usually transmitted by insect bites, and often cause serious diseases such as sleeping sickness, chagas disease, etc.

Trypanosomiasis

Any disease caused by a trypanosome.

Tubificids

Red blood worms, a family of red, tubivolous, oligochaete annelids (worms).

Ultrastructure

The fine structure of cells as seen with an ultra microscope.

Vascular plant

A plant having vascular bundles for liquid transport, such as phanerogams and Filicales. Mosses or algae are not vascular plants.

VDI Guideline

A guideline of the Association of German Engineers (Verein Deutscher Ingenieure).

Water body

A coherent section of water, i.e. a pond, lake,

Xeromorphic

Having an exterior structure and a shape that is adapted to dry living conditions.