Water particles that fall from the ATMOSPHERE.

Acidic water usually pH 2.5 to 4.5, which poisons the ecosystem and adversely affects plants, fishes, and mammals. It is caused by industrial pollutants, mainly sulfur oxides and nitrogen oxides, emitted into the atmosphere and returning to earth in the form of acidic rain water.

Woody, usually tall, perennial higher plants (Angiosperms, Gymnosperms, and some Pterophyta) having usually a main stem and numerous branches.

A climate which is typical of equatorial and tropical regions, i.e., one with continually high temperatures with considerable precipitation, at least during part of the year. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

The various physical methods which include wind, insects, animals, tension, and water, by which a plant scatters its seeds away from the parent plant.

A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)

Frozen water crystals that fall from the ATMOSPHERE.

Divisions of the year according to some regularly recurrent phenomena usually astronomical or climatic. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

The state of the ATMOSPHERE over minutes to months.

A plant genus of the family BOMBACACEAE. The fine silky hairs covering the seeds have been used for floatation, stuffing, and insulation.

A plant family of the order Bromeliales, subclass Zingiberidae, class Liliopsida (monocotyledons).

One of the Indian Ocean Islands off the southeast coast of Africa. Its capital is Antananarivo. It was formerly called the Malagasy Republic. Discovered by the Portuguese in 1500, its history has been tied predominantly to the French, becoming a French protectorate in 1882, a French colony in 1896, and a territory within the French union in 1946. The Malagasy Republic was established in the French Community in 1958 but it achieved independence in 1960. Its name was changed to Madagascar in 1975. (From Webster's New Geographical Dictionary, 1988, p714)

The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.

The science of studying the characteristics of the atmosphere such as its temperature, density, winds, clouds, precipitation, and other atmospheric phenomena and aiming to account for the weather in terms of external influences and the basic laws of physics. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

The longterm manifestations of WEATHER. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

The motion of air currents.

Contamination of the air, bodies of water, or land with substances that are harmful to human health and the environment.

The fusion of a male gamete with a female gamete from the same individual animal or plant.

Number of individuals in a population relative to space.

The variety of all native living organisms and their various forms and interrelationships.

A plant genus of the family TAXODIACEAE known for including some of the tallest trees.

The routing of water to open or closed areas where it is used for agricultural purposes.

A French overseas department on the northeast coast of South America. Its capital is Cayenne. It was first settled by the French in 1604. Early development was hindered because of the presence of a penal colony. The name of the country and the capital are variants of Guyana, possibly from the native Indian Guarani guai (born) + ana (kin), implying a united and interrelated race of people. (From Webster's New Geographical Dictionary, 1988, p418 & Room, Brewer's Dictionary of Names, 1992, p195)

Scattered islands in the Mediterranean Sea. The chief islands are the Balearic Islands (belong to Spain; Majorca and Minorca are among these), Corsica (belongs to France), Crete (belongs to Greece), CYPRUS (a republic), the Cyclades, Dodecanese and Ionian Islands (belong to Greece), MALTA (a republic), Sardinia and SICILY (belong to Italy). (From Webster's New Geographical Dictionary, 1988, p747)

A genus of trees of the Myrtaceae family, native to Australia, that yields gums, oils, and resins which are used as flavoring agents, astringents, and aromatics.

The spontaneous transformation of a nuclide into one or more different nuclides, accompanied by either the emission of particles from the nucleus, nuclear capture or ejection of orbital electrons, or fission. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

The motion of air relative to the earth's surface.

A republic in western Africa, south of GUINEA and east of COTE D'IVOIRE. Its capital is Monrovia.

A plant genus of the family FABACEAE. Members contain resins (RESINS, PLANT) and GLUCANS.

Seedless nonflowering plants of the class Filicinae. They reproduce by spores that appear as dots on the underside of feathery fronds. In earlier classifications the Pteridophyta included the club mosses, horsetails, ferns, and various fossil groups. In more recent classifications, pteridophytes and spermatophytes (seed-bearing plants) are classified in the Subkingdom Tracheobionta (also known as Tracheophyta).

The science dealing with the earth and its life, especially the description of land, sea, and air and the distribution of plant and animal life, including humanity and human industries with reference to the mutual relations of these elements. (From Webster, 3d ed)

The mangosteen plant family (sometimes classified as Guttiferae; also known as Hypericaceae) of the order THEALES, subclass Dilleniidae, class Magnoliopsida. It includes trees and shrubs with resinous, sticky sap, usually with broad-ended, oblong, leathery leaves with a strong, central vein, flowers with many stamens.

The fertilizing element of plants that contains the male GAMETOPHYTES.

The pattern of any process, or the interrelationship of phenomena, which affects growth or change within a population.

Total mass of all the organisms of a given type and/or in a given area. (From Concise Dictionary of Biology, 1990) It includes the yield of vegetative mass produced from any given crop.

A plant genus of the family POACEAE that contains the Poa p Ia allergen and allergen C KBGP.

Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)

Family of spider MITES, in the superfamily Tetranychoidea, suborder Trombidiformes.

A plant genus of the family Ephedraceae, order Ephedrales, class Gnetopsida, division Gnetophyta.

Water containing no significant amounts of salts, such as water from RIVERS and LAKES.

Techniques which study entities using their topological, geometric, or geographic properties and include the dimension of time in the analysis.

Substances or mixtures that are added to the soil to supply nutrients or to make available nutrients already present in the soil, in order to increase plant growth and productivity.

A plant division of GYMNOSPERMS consisting of cone-bearing trees and shrubs.

The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)

Calamities producing great damage, loss of life, and distress. They include results of natural phenomena and man-made phenomena. Normal conditions of existence are disrupted and the level of impact exceeds the capacity of the hazard-affected community.

This plant order includes 8 families, 66 genera, and about 1,800 species. These herbaceous perennials are mainly found in the wet tropics. Members include the banana family (MUSACEAE) and GINGER family (ZINGIBERACEAE).

Members of the group of vascular plants which bear flowers. They are differentiated from GYMNOSPERMS by their production of seeds within a closed chamber (OVARY, PLANT). The Angiosperms division is composed of two classes, the monocotyledons (Liliopsida) and dicotyledons (Magnoliopsida). Angiosperms represent approximately 80% of all known living plants.

Supplying a building or house, their rooms and corridors, with fresh air. The controlling of the environment thus may be in public or domestic sites and in medical or non-medical locales. (From Dorland, 28th ed)

The custard-apple plant family of the order Magnoliales, subclass Magnoliidae, class Magnoliopsida. Some members provide large pulpy fruits and commercial timber. Leaves and wood are often fragrant. Leaves are simple, with smooth margins, and alternately arranged in two rows along the stems.

Substances or organisms which pollute the water or bodies of water. Use for water pollutants in general or those for which there is no specific heading.

An island in the Malay Archipelago, east of Sumatra, north of Java, and west of Celebes. It is the third largest island in the world. Its name is a Portuguese alteration of BRUNEI, located on it. (From Webster's New Geographical Dictionary, 1988, p163; Room, Brewer's Dictionary of Names, 1992, p73)

The study of early forms of life through fossil remains.

Acceleration produced by the mutual attraction of two masses, and of magnitude inversely proportional to the square of the distance between the two centers of mass. It is also the force imparted by the earth, moon, or a planet to an object near its surface. (From NASA Thesaurus, 1988)

A family of the order DIPTERA that comprises the mosquitoes. The larval stages are aquatic, and the adults can be recognized by the characteristic WINGS, ANIMAL venation, the scales along the wing veins, and the long proboscis. Many species are of particular medical importance.

The ash, dust, gases, and lava released by volcanic explosion. The gases are volatile matter composed principally of about 90% water vapor, and carbon dioxide, sulfur dioxide, hydrogen, carbon monoxide, and nitrogen. The ash or dust is pyroclastic ejecta and lava is molten extrusive material consisting mainly of magnesium silicate. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

Insects that transmit infective organisms from one host to another or from an inanimate reservoir to an animate host.

Territory in north central Australia, between the states of Queensland and Western Australia. Its capital is Darwin.

A type of climate characterized by insufficient moisture to support appreciable plant life. It is a climate of extreme aridity, usually of extreme heat, and of negligible rainfall. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

The science, art or practice of cultivating soil, producing crops, and raising livestock.

The protection, preservation, restoration, and rational use of all resources in the total environment.

Contamination of bodies of water (such as LAKES; RIVERS; SEAS; and GROUNDWATER.)

INSECTS of the order Coleoptera, containing over 350,000 species in 150 families. They possess hard bodies and their mouthparts are adapted for chewing.

The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.

A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.

The above-ground plant without the roots.

The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.

Eukaryotes in the group STRAMENOPILES, formerly considered FUNGI, whose exact taxonomic level is unsettled. Many consider Oomycetes (Oomycota) a phylum in the kingdom Stramenopila, or alternatively, as Pseudofungi in the phylum Heterokonta of the kingdom Chromista. They are morphologically similar to fungi but have no close phylogenetic relationship to them. Oomycetes are found in both fresh and salt water as well as in terrestrial environments. (Alexopoulos et al., Introductory Mycology, 4th ed, pp683-4). They produce flagellated, actively motile spores (zoospores) that are pathogenic to many crop plants and FISHES.

Deoxyribonucleic acid that makes up the genetic material of CHLOROPLASTS.

The flow of water in enviromental bodies of water such as rivers, oceans, water supplies, aquariums, etc. It includes currents, tides, and waves.

The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.

Remains, impressions, or traces of animals or plants of past geological times which have been preserved in the earth's crust.

Very young plant after GERMINATION of SEEDS.

The external elements and conditions which surround, influence, and affect the life and development of an organism or population.

Plants whose roots, leaves, seeds, bark, or other constituent parts possess therapeutic, tonic, purgative, curative or other pharmacologic attributes, when administered to man or animals.

A plant family of the order Orchidales, subclass Liliidae, class Liliopsida (monocotyledons). All orchids have the same bilaterally symmetrical flower structure, with three sepals, but the flowers vary greatly in color and shape.

Means or process of supplying water (as for a community) usually including reservoirs, tunnels, and pipelines and often the watershed from which the water is ultimately drawn. (Webster, 3d ed)

The relationships of groups of organisms as reflected by their genetic makeup.

The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.