Habitats of Hamilton and Halton

GLOSSARY

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ACID:	A substance that, when added to water, increases the concentration of hydrogen ions (lowers the pH).
ALGAE:	small, sometimes single celled, aquatic plants that float freely in water; often referred to as phytoplankton.
ALKALINITY:	refers to the capability of a substance to neutralize acid (buffering capacity). A buffer is a solution to which an acid can be added without greatly changing the pH (the concentration of available H+ ions). Alkalinity is related to hardness because the main source of alkalinity is usually from carbonate rocks (limestone) that are mostly calcium carbonate. Some common alkaline things include baking soda, antacid pills and lime, which all neutralize acids. Some examples of common acidic things are vinegar (acetic acid)and orange juice (citric acid).
AQUATIC INSECTS:	insects that spend most of their lives underwater but which often spend their adult life outside of water (e.g. dragonflies, mosquitos, mayflies).
BACTERIA:	small, single celled organisms (neither animals nor plants) that lack a nucleus and live in many habitats including water, soil, animal animals and plants. They may be helpful or harmful to other organisms. Cyanobacteria are the only bacteria that, like plants, are able to photosynthesize.
BASE:	A substance that, when added to water, reduces the concentration of hydrogen ions (raises the pH).
BIODIVERSITY:	the variety of different species that inhabit an area. The more varied the species are, the more diverse is the biological community. Maintaining biodiversity helps to prevent species extinction and is often important for ecosystem health.
BIOMASS:	the amount of living tissue in an organism, population or community.
BUFFER:	a substance that enables a solution (e.g. water) to resist pH changes when an acid or base is added.
BUTTRESS ROOTS:	lower tree trunks and roots that have adapted to wet surroundings by forming what are called buttresses; strange raised roots that resemble bony knees held above the water.
CANOPY:	the forest layer formed by tree branches and their leaves
CATCHMENT:	an area within which all precipitation remains owing to topographic boundaries, such that this water is all ultimately channeled to one outlet. May also be called 'watershed' or 'drainage basin'.
CHLOROPHYLL:	molecules that plants use to convert sunlight and carbon dioxide to energy in the form of carbohydrates; responsible for the green colouration of most plants.
COVER:	is plant life that allows animals to hide and be protected from predation.
CREEK:	a small, natural waterway.
CUESTA:	a ridge formed by the protruding edge of gently tilted rock layers. Every cuesta has a steep slope where the rock layers are exposed on their edges called the 'escarpment'. They also have a more gradual slope on the other side of the ridge called the 'dip slope'.
DECOMPOSERS:	organisms that live by breaking down dead, decaying plant and/or animal matter, thereby creating waste products that contribute to soil formation and nutrient availability.
DRAINAGE BASIN:	an area defined at its margins by a topographic high, such that all of the water that falls within the area remains within it until the water reaches an outlet, often where a major creek reaches a lake. The term 'drainage basin' is interchangeable with the terms 'watershed' and 'catchment'.
EMERGENT VEGETATION:	aquatic vegetation that is protruding out of the water: emergent plants have their roots underwater, often rooted in the sediment, and most of their leaves above water, such as cattails (Typha spp.).
EPHEMERAL:	lasting a short time, being present very briefly; as in ephemeral creek (one which dries up for part of the year) and Ephemeroptera (the Mayfly Order of short-lived aquatic insects).
EPILIMNION:	the warmer, upper layer of a lake.
ESCARPMENT:	the steep slope of a cuesta where rock layers are often exposed. In common usage the entire cuesta is referred to as an escarpment.
EUTROPHIC:	highly fertile and nutrient-enriched. A state in which a body of water has an overabundance of phytoplankton (algae), one sign that there is too much organic pollution, such as sewage and domestic water, going into the water. Lakes like this appear green because they have so much algae.
EXTINCT:	no longer in existence, as in species extinction, the ceasing of a species to exist in life. Species extinction is one major effect of human population expansion and leads to a decrease in biodiversity.
EXTIRPATED:	means locally extinct, that is the species may not be extinct everywhere but it is not found at all in that area.
FISH BARRIER:	a physical barrier that keeps out invasive species like Carp and allows native fish to survive and reproduce in an enclosed area.
FLOATING VEGETATION:	vegetation which has its leaves on the water surface and their roots dangling down below.
FORB:	a shortened form of the word Euphorbiaceae, which is a family of plants that includes some well-known grassland species such as Euphorbia corollata (Showy Spurge). While the entire non-grass plant population in grasslands is often called 'forbs', many non-grass plants in grasslands are not in the euphorbiaceae at all.
GLACIAL SCOUR:	during periods when the glaciers were growing and advancing southward, they scraped the land below them and pushed the accumulated piles of debris such as rocks, sand, silt and clay along in front of them as they moved. This scraping resulted in the deepening of river valleys, the flattening of bedrock and the levelling of hills.
GLACIAL TILL:	a jumble of materials that has been deposited by glaciers as they advance or retreat across a landscape, including boulders, rocks and gravel in a matrix of sand, clay or silt.
GOLDEN HORSESHOE:	the area around the western end of Lake Ontario that is known for being highly populated and for its wealth. This strip of urban and industrial area on the lakeshore is one of the most populated urban areas in Canada. Currently 4,366,500 people live in the greater Toronto area and 618,800 in Hamilton (2001 Census, Stats Canada).
GRASSLANDS:	grass-dominated areas where few or no trees grow. Includes prairies and savannas.
HABITAT CORRIDORS:	pathways of natural habitat, occurring within larger areas that have been developed by humans, that attract wildlife and act as safe passages for wildlife between neighbouring natural areas. These are called 'habitat corridors' because they are like connections between natural areas. These are often along creek riparian zones that run through cropped fields or urban areas.
HABITAT ISLANDS:	zones of natural habitat, occurring within larger areas that have been developed by humans, that attract wildlife and that act as safe areas for wildlife. between neighbouring natural areas. These are called 'habitat islands' because they are like natural islands in a sea of development. Habitat islands allow animals and plants to access more resources, have a better chance at survival, and maintain genetic diversity in their populations because of improved breeding opportunities.
HERBACEOUS PLANTS:	plants whose above ground growth dies down to the ground each year, but whose root systems remain alive and lie dormant until spring when new growth occurs above the ground. In comparison, woody plants maintain branches over the winter that can tolerate cold temperatures and re-sprout leaves in the spring.
HERBIVORE:	an animal for which plants make up its primary food source.
HYDROPHILIC:	'water-adapted' or 'water-loving'. 'Hydrophytic' means the same thing. Hydrophilic plants have an ability to thrive in waterlogged conditions.
HYDROPHYTIC:	'water-adapted' or 'water-loving'. 'Hydrophilic' means the same thing. Hydrophytic plants have an ability to thrive in waterlogged conditions.
HYPOLIMNION:	the colder, lower layer of a lake.
INVERTEBRATES:	animals without an internal skeleton, often having an exoskeleton instead (e.g insects and spiders, slugs, jellyfish, coral).
LICHEN:	an associations between an algae and a fungus living in a mutualistic state of symbiosis on trees or rocks, resembling one single organism.
MARSHES:	wetlands with soils that are less organic than other wetlands, usually characterised by emergent vegetation such as cattails. Marshes usually have an equal area of open water and vegetation.
MEADOW:	an ecosystem in transition from an open, disturbed condition to a forested state having a variable mixture of grasses, herbaceous plants and often small shrubs or trees.
MEROMICTIC LAKES:	lakes that that do not mix completely, usually having extremely cold lower layers as often happens in very deep lakes. These lakes usually have such low oxygen levels in the cold, lower hypolimnion layer that decomposition is greatly limited.
MICHIGAN BASIN:	a roughly circular depression in the earth's crust centered under the state of Michigan, formed of layers of sedimentary rock created over 420 million years ago by accumulated layers of detritus in the Michigan Sea.
MICHIGAN SEA:	a sea that shrank and grew in area several times over a period of 25 million years, between 445 million and 420 million years ago, over what is now the Michigan Basin.
MONOCULTURES:	areas where only one plant is being grown, such as crops of wheat, tobacco, soybeans or corn. Biologically non-diverse areas.
MORAINES (GLACIAL MORAINES):	raised ridges formed by piles of materials generated by glacial scraping. When the glaciers melted and retreated, they left behind piles of material that they had scraped up and pushed along to the edges of their area of movement.
MOSS:	small, non-vascular plants, e.g. Sphagnum moss (peat moss).
NUTRIENT LOAD:	the mass of nutrients carried by water into surrounding waterways, over a period of time. Because of the use of fertilisers and manure, water that passes through agricultural soils often carries a high 'nutrient load' into local creeks. An overabundance of nutrients in water causes algae to grow, use up oxygen, and reduce the availability of oxygen to other organisms such as fish.
NUTRIENTS:	compounds that cause living organisms to grow and remain healthy. In this context we are referring to plant nutrients. These compounds include nitrogen, phosphorus and potassium. Nutrients in water cause algae to grow, use up oxygen, and reduces the availability of oxygen to other organisms such as fish.
OLD GROWTH FOREST:	a forest that can be characterized by ecological conditions where large trees in the most mature stages of their life cycles generally dominate the forest vegetation. These forests are often thought to be in an state of equilibrium (balance).
OLIGOTROPHIC:	a state in which a lake has clear water, without too much algae and is not nutrient rich (possibly nutrient poor).
ORGANIC:	a word with several meanings. In a geological or ecological context it means being made of material that is, or once was alive, or material having its origins in living material such as decomposed plant tissues. All animals and plants are organic by this definition, as are soils that have been created through the breakdown of animal or plant tissues. Organic can also mean not being made by people (natural occurring). By this definition, oranges are organic because they grow through a natural process, but vitamin C pills are not because they are made by people. Organic can also refer to food (fruits, vegetables, meats, dairy products) that is grown without the use of pesticides, herbicides, or certain artificial fertilizers. Finally, organic can also be used to describe the appearance of something that appears naturalistic rather than artificial, such as a piece of artwork or a garden.
PEATLANDS:	wetlands where the soil is highly organic because is it formed mostly from incompletely decomposed plants. This soil is called peat and its presence is what defines peatlands.
PHOTOSYNTHESIS:	the chemical process by which plants (and some bacteria) use chorophyll and carbon dioxide to capture and use the energy of the sun to produce carbohydrates used by the plant (i.e. glucose, a sugar) and oxygen, which is released to the atmosphere.
PHYTOPLANKTON:	algae that are present in lakes and make up part of the bottom of the aquatic food chain.
POLLUTANTS:	substances that have a harmful effect on human and/or ecosystem health when present in high enough concentrations in water, air or soil. The concentration that makes a pollutant harmful varies between substances, some are only harmful in large amounts, some are harmful in very small amounts. Some major environmental pollutants are acid rain, phosphorus (a nutrient), POPs ('persistent organic pollutants', e.g. PCBs - poly-chlorinated biphenyls), sewage waste, mercury and other heavy metals.
PRAIRIE:	a grassland that is adapted to conditions where evaporation exceeds precipitation.
PRECIPITATION:	water that falls to the earth's surface in several forms including rain and snow, and that is caused by the conglomeration of water molecules in the earth's atmosphere.
PRODUCTIVITY:	usually defined as the amount of biomass, or living tissue, that an ecosystem produces over a period of time.
RAPTORS:	birds of prey such as hawks, eagles and falcons.
RESERVOIR:	artificial lakes that are the result of river damming, often to control flooding and regulate stream flow or to hold water for use by city residents.
RIPARIAN ZONE:	the land area along either side of a waterway, often habitat for plants adapted to wet soils and animals that use the waterway and this zone for their food and shelter.
RIVER:	a large natural waterway.
SATURATED:	waterlogged (full of water).
SAVANNA:	a grassland which features scattered trees that are few enough in number not to affect light penetration to the ground.
SUBMERGENT VEGETATION:	aquatic vegetation which has its entire mass underwater.
SWAMPS:	forested wetlands.
SYMBIOSIS:	a relationship between two organisms defined as 'living together. It is not always a beneficial relationship and may be 'parasitism' where one organism feeds off of the other in a harmful way, or may be 'mutualism' where both organisms benefit.
THERMAL STRATIFICATION:	the development of warmer, upper layers and colder, lower layers caused by the sinking of cold water and rising of warm water. Lakes are stratified into these layers because warm water is less dense and heavy than cold water. As the surface water warms over the summer this warmer water stays near the surface and the cooler water stays near the bottom. Air also follows this behaviour, warm air rises and cool air falls. This chemical reaction can be described by the following simple equation: 6CO 2+ 6 H2O+light energy =C6H12 O6+ 6 O2
TOPOGRAPHY:	the shape and configuration of the surface of the land, for example hilly or flat.
TREE-LINE:	the northerly limit beyond which trees can no longer grow in significant numbers; also the altitude on a mountainside beyond which trees no longer grow in significant numbers.
TURNOVER:	the mixing of the thermally stratified lake water layers. This occurs in the autumn when the upper water layer cools and sinks, forcing the water near the bottom towards the surface. Lakes that freeze over in the winter turnover again in the spring as the upper ice layer melts and this very cold water sinks to the bottom.
UNDERSTOREY:	the layer of plant life that grows beneath the branches of the trees above (the canopy), often consisting of small shrubs and herbaceous plants.
UNESCO:	the United Nations' Educational, Scientific and Cultural Organization which designates such things as World Biosphere Reserves.
URBAN HEAT ISLAND:	the phenomenon of urban centres being are warmer by a degree or two than the surrounding area. This affect is a product of the heat that is generated by all of the buildings present in urban areas and of their ability to absorb solar energy and release it as detectable heat.
URBAN SPRAWL:	the expansion of urban areas across the landscape, and the conversion of forested areas wetlands and agriculture areas to urban areas. Urban sprawl includes the expansion of major roadways, not just housing and commercial sites.
VASCULAR TISSUE:	plant cell tissue that is used to transport nutrients and water throughout a plant; as veins and arteries are to animals. The two kind of vascular tissue are xylem (used mainly for water) and phloem (used more for nutrients).
WATERSHED:	is an area of water drainage bounded by a relatively high topographic margin known as the drainage 'divide'. Water falling anywhere within the boundary of a watershed is ultimately directed to one outlet. The terms 'catchment' and 'drainage basin' mean the same thing as watershed.
WATERWAY:	a channel or paths through which water flows. The largest natural waterways are generally called 'rivers', while the terms 'stream', 'creek' and 'brook' can be used interchangeably for natural waterways that are smaller than rivers. In the United Kingdom you might hear the terms 'race', 'brook', 'rindle, 'burn' and 'runnel' used in the same way. Canals are artificial waterways built by people to cause water to flow/be present in a path chosen for a purpose such as the transport of ships.
WETLAND:	"land that is saturated with water long enough to promote wetland or aquatic processes as indicated by poorly drained soils, hydrophytic vegetation and various kinds of biological activity which are adapted to a wet environment"(Wetlands of Canada, Tarnocai et al., 1988). Wetlands occur in depressions, along lake, pond and river edges and are the result of the presence of water that is unable to escape. They usually have a mix of open water and vegetated areas, with this balance varying with location.
WISCONSIN GLACIATION:	a period of glaciation that occurred between one million and 14 000 years ago, when ice sheets were advancing and retreating in cycles across this part of North America. These ice sheets were large and often over two kilometres thick and extended as far south as Wisconsin and northern New York State so that this is period is often called the Wisconsin Glaciation.
WOODY PLANTS:	plants that maintain branches over the winter that can tolerate cold temperatures and re-sprout leaves in the spring. In comparison, herbaceous plants die down to the ground each year, with their root system lying dormant until spring.
ZOOPLANKTON:	very small, often free-floating, animals that are present in lakes and make up part of the bottom of the aquatic food chain.