Plant community in the context of "Vegetation"

Soil retrogression and degradation are two regressive evolution processes associated with the loss of equilibrium of a stable soil. Retrogression is primarily due to soil erosion and corresponds to a phenomenon where succession reverts the land to its natural physical state. Degradation or pedolysis is an evolution, different from natural evolution, related to the local climate and vegetation. It is due to the replacement of primary plant communities (known as climax vegetation) by the secondary communities. This replacement modifies the humus composition and amount, and affects the formation of the soil. It is directly related to human activity. Soil degradation may also be viewed as any change or ecological disturbance to the soil perceived to be deleterious or undesirable.

According to the Center for Development Research at the University of Bonn and the International Food Policy Research Institute in Washington, the quality of 33% of pastureland, 25% of arable land and 23% of forests has deteriorated globally over the last 30 years. 3.2 billion people are dependent on this land.

In biology, the canopy is the aboveground portion of a plant cropping or crop, formed by the collection of individual plant crowns. In forest ecology, the canopy is the upper layer or habitat zone, formed by mature tree crowns and including other biological organisms (epiphytes, lianas, arboreal animals, etc.). The communities that inhabit the canopy layer are thought to be involved in maintaining forest diversity, resilience, and functioning. Shade trees normally have a dense canopy that blocks light from lower growing plants.

Early observations of canopies were made from the ground using binoculars or by examining fallen material. Researchers would sometimes erroneously rely on extrapolation by using more reachable samples taken from the understory. In some cases, they would use unconventional methods such as chairs suspended on vines or hot-air dirigibles, among others. Modern technology, including adapted mountaineering gear, has made canopy observation significantly easier and more accurate, allowed for longer and more collaborative work, and broaddened the scope of canopy study.

A forest stand is a contiguous community of trees sufficiently uniform in composition, structure, age, size, class, distribution, spatial arrangement, condition, or location on a site of uniform quality to distinguish it from adjacent communities.

A forest is a "collection of stands" also utilizing the practices of forestry. Stand level modelling is a type of modelling in the forest sciences in which the main unit is a forested stand.

Garrigue or garigue (/ɡəˈriːɡ/ gə-REEG), also known as phrygana (Greek: φρύγανα [ˈfriɣana], n. pl.), is a type of low scrubland ecoregion and plant community in the Mediterranean forests, woodlands, and scrub biome.

It is found on limestone soils in southern France and around the Mediterranean Basin, generally near the seacoast where the moderated Mediterranean climate provides annual summer drought. It is an anthropogenic degradation and succession form of former evergreen oak forests that existed until around 2500 years BCE.

The crown of a plant is the total of an individual plant's aboveground parts, including stems, leaves, and reproductive structures. A plant community canopy consists of one or more plant crowns growing in a given area.

The crown of a woody plant (tree, shrub, liana) is the branches, leaves, and reproductive structures extending from the trunk or main stems.

Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It may be the mature vegetation type in a particular region and remain stable over time, or it may be a transitional community that occurs temporarily as the result of a disturbance, such as fire. A stable state may be maintained by regular natural disturbance such as fire or browsing.

Shrubland may be unsuitable for human habitation because of the danger of fire. The term was coined in 1903.