Nevada Natural Heritage Program (brief) Ecological Glossary:
| Annual Grassland | Annuals are plants that live out their entire life cycle within a single year. Few native grasses in Nevada are annuals. Rather, most of Nevada's grasses live for many years (perennial), often resulting in a clumped growth form. Most annual grasslands in Nevada are dominated by cheatgrass, a species from Eurasia, and other non-native weeds. Compare to bunch grass. |
| Biological Soil Crust | Living organisms that cover and/or bind the surface of the soil (up to several cm deep). Crusts in good condition are composed of cyanobacteria (blue-green algae), bryophytes (mosses and liverworts), and lichens, often along with various microscopic bacteria and non-lichen fungi. See the Biological Soil Crusts home page and the Nevada Lichens web site for more information. |
| Bunch Grass | Any of a number of grass species that live for more than one year and have a clumped growth form. Most native grasses in Nevada are bunch grasses. Some non-native species are too, such as crested wheatgrass. Compare to annual grassland. |
| Community | The collection of all organisms that live together on a relatively uniform area of land. A plant communities would refer to the vegetative portion of the whole community. NvNHP generally considers the plant community to include 'lower plants' such as mosses, and fungi such as lichens and mushrooms. However, the 'lower plants' and fungi are frequently ignored. |
| Condition | Describing the ability of a community or ecosystem to function naturally. Good condition refers to a strong ability for natural function while poor condition refers to dysfunction or unnatural functions. Causes of poor condition include (but are not limited to) invasion by non-native species, losses of native species, and changes in the proportions of native species.. |
| Disturbance | The changing of a community (species addition, loss, or change in proportions) from external factors. Examples of disturbance include wildfire, grazing, and human development. Disturbance is not necessarily bad and can even be a natural part of an ecosystem necessary to maintain proper function (e.g. Forest fires in the Sierra Mountains) |
| Ecosystem | A collection of tightly interacting communities which can be viewed as a single unit with inputs, outputs, and internal processes. Ecosystems can be narrowly defined or broadly defined (e.g. the basin big sagebrush ecosystem or the more general sagebrush ecosystem) |
| Environment | All the factors which might affect organisms, including abiotic influences (soils, air temperature, rainfall, etc.) and biotic influences (other organisms) |
| Fragmentation | The breaking up of an organism's habitat into discontinuous chunks, particularly for organisms that have difficulty moving from one of those chunks to another. Fragmentation can be caused by removal of vegetation over large areas for human development, or even by small roads breaking up the habitat of (for example) amphibians that are resistant to crossing roads or are frequently killed when crossing roads. Power lines can fragment sage grouse habitat by providing convenient perches for predators such as hawks and ravens. |
| Fungi | A kingdom of organisms, many of which are highly evolved, that are separate from the plant and animal kingdoms (they are actually more closely related to the animal kingdom even though they were once thought to be plants). While fungi include unappreciated organisms such as molds and the athletes-foot causing fungus, they also include beautiful and complex organisms such as mushrooms and lichens. |
| Habitat | A community that is appropriate for a particular organism at some point in its life. Habitat is most often used to refer to the plant community used by an animal, but can also be used to refer to the environment used by a plant, fungus, or other organism. |
| Healthy | A word often used to describe communities or ecosystems that are in good condition. Most ecologists are now trying to stop using this word as it implies a lack of disease or disturbance, yet many ecosystems require disease or disturbance to maintain a good condition. |
| Intact | A community or ecosystem that is maintaining proper function and has not lost significant species (for communities) or significant communities (for ecosystems). Typically there will also not be a significant amount of invasive weeds. |
| Invaded | A community that now includes species that would not have naturally been present. The species is usually not native to the area. |
| Invasive | A species capable of asserting itself in communities where it did not naturally occur. Usually a species not native to the area. |
| Lichen | A fungus that harbors algae within it's body where the fungus and algae function as if they were a single organism and are indistinguishable without a microscope. Fungi alone are not capable of photosynthesis, however the inclusion of algae allows lichens to be photosynthetic and thus somewhat plant-like. |
| Native | A species that naturally occurred in the area prior to inter-continental travel by people. Such travel has resulted in transportation of many species between the Americas and Eurasia. |
| Weed | A species of plant growing in an area it did not naturally occur in. Usually a species not native to the area. |