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 is an evolution, different from natural evolution, related to the local climate and vegetation. It is due to the replacement of primary plant communities 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.
A psammosere is the sequence of plant succession in stages, initiated on sand. It is seral community, an ecological succession that began life on newly exposed coastal sand. Most common psammoseres are sand dune systems.
Ecological succession is the process of change in the species that make up an ecological community over time.
The Tasmanian temperate rain forests are a temperate broadleaf and mixed forests ecoregion in western Tasmania. The ecoregion is part of the Australasian realm, which includes Tasmania and Australia, New Zealand, New Guinea, New Caledonia, and adjacent islands.
Rangelands are grasslands, shrublands, woodlands, wetlands, and deserts that are grazed by domestic livestock or wild animals. Types of rangelands include tallgrass and shortgrass prairies, desert grasslands and shrublands, woodlands, savannas, chaparrals, steppes, and tundras. Rangelands do not include forests lacking grazable understory vegetation, barren desert, farmland, or land covered by solid rock, concrete, or glaciers.
The pedosphere is the outermost layer of the Earth that is composed of soil and subject to soil formation processes. It exists at the interface of the lithosphere, atmosphere, hydrosphere and biosphere. The pedosphere is the skin of the Earth and only develops when there is a dynamic interaction between the atmosphere, biosphere, lithosphere and the hydrosphere. The pedosphere is the foundation of terrestrial life on Earth.
Primary succession is the beginning step of ecological succession where species known as pioneer species colonize an uninhabited site, which usually occurs in an environment devoid of vegetation and other organisms.
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 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.
A hydrosere is a plant succession which occurs in an area of fresh water such as in oxbow lakes and kettle lakes. In time, an area of open freshwater will naturally dry out, ultimately becoming woodland. During this change, a range of different landtypes such as swamp and marsh will succeed each other.
A lithosere is a plant succession that begins life on a newly exposed rock surface, such as one left bare as a result of glacial retreat, tectonic uplift as in the formation of a raised beach, or volcanic eruptions. For example, the lava fields of Eldgjá in Iceland where Laki and Katla fissures erupted in the year 935 and the solidified lava has, over time, begun to form a lithosere.
Sand dune ecology describes the biological and physico-chemical interactions that are a characteristic of sand dunes.
Wistman's Wood is one of Britain's last remaining ancient temperate rainforests and one of three remote high-altitude oakwoods on Dartmoor in Devon, England. The first written document to mention Wistman's Wood date to the 1600s, while more recent tree-ring studies show that individual trees could be many hundreds of years old.
Ceratodon purpureus is a dioicous moss with a color ranging from yellow-green to red. The height amounts to 3 centimeters. It is found worldwide, mainly in urban areas and next to roads on dry sand soils. It can grow in a very wide variety of habitats, from polluted highway shoulders and mine tailings to areas recently denuded by wildfire to the bright slopes of Antarctica. Its common names include redshank, purple forkmoss, ceratodon moss, fire moss, and purple horn toothed moss.
A beech–maple forest or a maple beech forest is a climax mesic closed canopy hardwood forest. It is primarily composed of American beech and sugar maple trees which co-dominate the forest and which are the pinnacle of plant succession in their range. A form of this forest was the most common forest type in the Northeastern United States when it was settled by Europeans and remains widespread but scattered today.
A thorn forest is a dense scrubland with vegetation characteristic of dry subtropical and warm temperate areas with a seasonal rainfall averaging 250 to 500 mm.
Crustose lichens are lichens that form a crust which strongly adheres to the substrate, making separation from the substrate impossible without destruction. The basic structure of crustose lichens consists of a cortex layer, an algal layer, and a medulla. The upper cortex layer is differentiated and is usually pigmented. The algal layer lies beneath the cortex. The medulla fastens the lichen to the substrate and is made up of fungal hyphae. The surface of crustose lichens is characterized by branching cracks that periodically close in response to climatic variations such as alternate wetting and drying regimes.
Vegetation classification is the process of classifying and mapping the vegetation over an area of the Earth's surface. Vegetation classification is often performed by state based agencies as part of land use, resource and environmental management. Many different methods of vegetation classification have been used. In general, there has been a shift from structural classification used by forestry for the mapping of timber resources, to floristic community mapping for biodiversity management. Whereas older forestry-based schemes considered factors such as height, species and density of the woody canopy, floristic community mapping shifts the emphasis onto ecological factors such as climate, soil type and floristic associations. Classification mapping is usually now done using geographic information systems (GIS) software.
Rhytidiadelphus loreus, also commonly known as Lanky Moss and Little Shaggy Moss, is a nonvascular "feather moss" species that is a key component of a healthy, thriving forest ecosystem. Lanky moss grows in North America, Canada and Europe. It is primarily a coastal species that grows in moist, coniferous and deciduous forests, acidic grasslands and in the UK, heathy slopes on mountains. It grows on decaying logs, the forest floor and as an epiphyte on living trees. Its key functions in the ecosystem are water retention and temperature insulation.
Located in the Scandinavian Peninsula, Sweden is a mountainous country dominated by lakes and forests. Its habitats include mountain heath, montane forests, tundra, taiga, beech forests, rivers, lakes, bogs, brackish, marine coasts, and cultivated land. The climate of Sweden is mild for a country at this latitude, largely owing to the significant maritime influence.
Chena is the oldest cultivation method in Sri Lanka, it goes far back as more than 5,000 years. it the dry zone, the recovery of a chena plot proceeds through various stages of succession, (active chena, abandoned chena, chena re-growth, scrub with pioneer three species, scrub with secondary tree species, secondary forest, secondary forest with primary tree species and finally, the climax or steady-state forest. The smooth progress of their recovery process depends on the absence of further disturbances, such as a re-cultivation of active or abandoned chena plots, fire and human development activates such as settlements. However, in the wet zone, the process of vegetational succession and recovery take more complex routes. In moderately degraded site where the soil surface is nit servery exposed, vegetation succession can be relatively rapid with the appearance of pioneer species and then secondary species which are eventually replaced by primary species, if left intact. In contrast, highly degraded sites, (e.g:- exposed to elements of weather, the vegetation will not recover up to the level of a forest, but remain as fenlands or grasslands for a very long time. The sensitive Red-Yellow podzolic soil, on exposure, transforms into a hard laterite and becomes impoverished due to erosion of its humus layer. This edaphic transformation is least conductive to the appearance of afforest vegetation, but usually supports inly a low-stature vegetation such as fenland dominated by kekilla A new chena, created by setting fire to it, is called a Nawadeli Hena. Those Chenas are fertile. The term Nawadeli Sena has been mentioned i the Saddharma Rathnawaliya as well. In some parts of Sri Lanka, a different term has been given to the term Nawadeli Sea. It says the term Nawadeli Sena is used for the cultivation of the nine plants, namely finger millet, Kollu, Undu, Green Gram, Corn, Millet, Dill and Amu. The villagers in Anuradhapura had given the name Kanaththa to name the Chenas prepared for cultivation after giving it up for a short while.
