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Climax species, also called late seral , late-successional, K-selected or equilibrium species, are plant species that can germinate and grow with limited resources; e.g., they need heat exposure or low water availability. [1] They are the species within forest succession that are more adapted to stable and predictable environments, and will remain essentially unchanged in terms of species composition for as long as a site remains undisturbed. [2]
The seedlings of climax species can grow in the shade of the parent trees, ensuring their dominance indefinitely. The presence of climax species can also reduce the prevalence of other species within an ecosystem. [3] However, a disturbance, such as fire, may kill the climax species, allowing pioneer or earlier successional species to re-establish for a time. [4] They are the opposite of pioneer species, also known as ruderal, fugitive, opportunistic or R-selected species, in the sense that climax species are good competitors but poor colonizers, whereas pioneer species are good colonizers but poor competitors. [5]
Given the prevailing ecological conditions, climax species dominate the climax community. When the pace of succession slows down as the result of ecological homeostasis, the maximum permitted biodiversity is reached. [6] Their reproductive strategies and other adaptive characteristics can be considered more sophisticated than those of opportunistic species. [7]
Through negative feedback, they adapt themselves to specific environmental conditions. Climax species are mostly found in forests. Climax species, closely controlled by carrying capacity, follow K strategies, wherein species produce fewer numbers of potential offspring, but invest more heavily in securing the reproductive success of each one to the micro-environmental conditions of its specific ecological niche. Climax species might be iteroparous, energy consumption efficient and nutrient cycling. [8]
The idea of a climax species has been criticized in recent ecological literature. [9] Any assessment of successional states depends on assumptions about the natural fire regime. But the idea of a dominant species is still widely used in silvicultural programs and California Department of Forestry literature.[ citation needed ]
White spruce (Picea glauca) is an example of a climax species in the northern forests of North America due to its ability to adapt to resource scarce, stable conditions, it dominates Northern forest ecosystem in the absence of a disturbance. [10]
Other examples of climax species in old-growth forests:
In ecology, edge effects are changes in population or community structures that occur at the boundary of two or more habitats. Areas with small habitat fragments exhibit especially pronounced edge effects that may extend throughout the range. As the edge effects increase, the boundary habitat allows for greater biodiversity.
In scientific ecology, climax community or climatic climax community is a historic term for a community of plants, animals, and fungi which, through the process of ecological succession in the development of vegetation in an area over time, have reached a steady state. This equilibrium was thought to occur because the climax community is composed of species best adapted to average conditions in that area. The term is sometimes also applied in soil development. Nevertheless, it has been found that a "steady state" is more apparent than real, particularly across long timescales. Notwithstanding, it remains a useful concept.
Ecological succession is the process of change in the species that make up an ecological community over time.
Picea mariana, the black spruce, is a North American species of spruce tree in the pine family. It is widespread across Canada, found in all 10 provinces and all 3 territories. It is the official tree of the province of Newfoundland and Labrador and is that province's most numerous tree. The range of the black spruce extends into northern parts of the United States: in Alaska, the Great Lakes region, and the upper Northeast. It is a frequent part of the biome known as taiga or boreal forest.
Picea rubens, commonly known as red spruce, is a species of spruce native to eastern North America, ranging from eastern Quebec and Nova Scotia, west to the Adirondack Mountains and south through New England along the Appalachians to western North Carolina. This species is also known as yellow spruce, West Virginia spruce, eastern spruce, and he-balsam. Red spruce is the provincial tree of Nova Scotia.
In spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant. Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vectors, such as the wind, and living (biotic) vectors such as birds. Seeds can be dispersed away from the parent plant individually or collectively, as well as dispersed in both space and time. The patterns of seed dispersal are determined in large part by the dispersal mechanism and this has important implications for the demographic and genetic structure of plant populations, as well as migration patterns and species interactions. There are five main modes of seed dispersal: gravity, wind, ballistic, water, and by animals. Some plants are serotinous and only disperse their seeds in response to an environmental stimulus. These modes are typically inferred based on adaptations, such as wings or fleshy fruit. However, this simplified view may ignore complexity in dispersal. Plants can disperse via modes without possessing the typical associated adaptations and plant traits may be multifunctional.
Primary succession is the beginning step of ecological succession after an extreme disturbance, which usually occurs in an environment devoid of vegetation and other organisms. These environments are typically lacking in soil, as disturbances like lava flow or retreating glaciers scour the environment clear of nutrients.
Restoration ecology is the scientific study supporting the practice of ecological restoration, which is the practice of renewing and restoring degraded, damaged, or destroyed ecosystems and habitats in the environment by active human interruption and action. Ecological restoration can reverse biodiversity loss, combat climate change and support local and global economies.
The intermediate disturbance hypothesis (IDH) suggests that local species diversity is maximized when ecological disturbance is neither too rare nor too frequent. At low levels of disturbance, more competitive organisms will push subordinate species to extinction and dominate the ecosystem. At high levels of disturbance, due to frequent forest fires or human impacts like deforestation, all species are at risk of going extinct. According to IDH theory, at intermediate levels of disturbance, diversity is thus maximized because species that thrive at both early and late successional stages can coexist. IDH is a nonequilibrium model used to describe the relationship between disturbance and species diversity. IDH is based on the following premises: First, ecological disturbances have major effects on species richness within the area of disturbance. Second, interspecific competition results in one species driving a competitor to extinction and becoming dominant in the ecosystem. Third, moderate ecological scale disturbances prevent interspecific competition.
In ecology, a disturbance is a temporary change in environmental conditions that causes a pronounced change in an ecosystem. Disturbances often act quickly and with great effect, to alter the physical structure or arrangement of biotic and abiotic elements. A disturbance can also occur over a long period of time and can impact the biodiversity within an ecosystem.
Translocation in wildlife conservation is the capture, transport and release or introduction of species, habitats or other ecological material from one location to another. It contrasts with reintroduction, a term which is generally used to denote the introduction into the wild of species from captive stock. The International Union for the Conservation of Nature (IUCN) catalogues translocation projects for threatened species around the globe.
Bolboschoenus fluviatilis, the river bulrush, is a species of flowering plant in the sedge family, Cyperaceae. Its range includes Australia, New Zealand, New Caledonia, Canada, the United States, and northeastern Mexico. B. fluviatilis and its fruits are important as food sources for waterfowl such as geese, ducks, bitterns, and swans. It also provides cover and nesting sites for these and other species of birds, as well as small mammals. Like other Bolboschoenus species, B. fluviatilis has strong tubers and rhizomes which help to stabilize intertidal habitats by preventing erosion.
Ecological dominance is the degree to which one or several species have a major influence controlling the other species in their ecological community or make up more of the biomass. Both the composition and abundance of species within an ecosystem can be affected by the dominant species present.
In ecology, a priority effect refers to the impact that a particular species can have on community development as a result of its prior arrival at a site. There are two basic types of priority effects: inhibitory and facilitative. An inhibitory priority effect occurs when a species that arrives first at a site negatively affects a species that arrives later by reducing the availability of space or resources. In contrast, a facilitative priority effect occurs when a species that arrives first at a site alters abiotic or biotic conditions in ways that positively affect a species that arrives later. Priority effects are a central and pervasive element of ecological community development that have significant implications for natural systems and ecological restoration efforts.
Riparian-zone restoration is the ecological restoration of riparian-zonehabitats of streams, rivers, springs, lakes, floodplains, and other hydrologic ecologies. A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the fifteen terrestrial biomes of the earth; the habitats of plant and animal communities along the margins and river banks are called riparian vegetation, characterized by aquatic plants and animals that favor them. Riparian zones are significant in ecology, environmental management, and civil engineering because of their role in soil conservation, their habitat biodiversity, and the influence they have on fauna and aquatic ecosystems, including grassland, woodland, wetland or sub-surface features such as water tables. In some regions the terms riparian woodland, riparian forest, riparian buffer zone, or riparian strip are used to characterize a riparian zone.
Forest restoration is defined as “actions to re-instate ecological processes, which accelerate recovery of forest structure, ecological functioning and biodiversity levels towards those typical of climax forest” i.e. the end-stage of natural forest succession. Climax forests are relatively stable ecosystems that have developed the maximum biomass, structural complexity and species diversity that are possible within the limits imposed by climate and soil and without continued disturbance from humans. Climax forest is therefore the target ecosystem, which defines the ultimate aim of forest restoration. Since climate is a major factor that determines climax forest composition, global climate change may result in changing restoration aims. Additionally, the potential impacts of climate change on restoration goals must be taken into account, as changes in temperature and precipitation patterns may alter the composition and distribution of climax forests.
In ecology regeneration is the ability of an ecosystem – specifically, the environment and its living population – to renew and recover from damage. It is a kind of biological regeneration.
The wood-pasture hypothesis is a scientific hypothesis positing that open and semi-open pastures and wood-pastures formed the predominant type of landscape in post-glacial Europe, rather than the common belief of primeval forests. The hypothesis proposes that such a landscape would be formed and maintained by large wild herbivores. Although others, including Oliver Rackham, who criticised the idea of an all-encompassing, dark primeval forest in pre-neolithic Europe, had previously expressed similar ideas, it was Dutch researcher Frans Vera, who, in his 2000 book Grazing Ecology and Forest History, first developed a comprehensive framework for such ideas and formulated them into a theorem. Vera's proposals, although highly controversial, came at a time when the role grazers played in woodlands was increasingly being reconsidered, and are credited for ushering in a period of increased reassesment and interdisciplinary research in European conservation theory and practice. Although Vera largely focused his research on the European situation, his findings could also be applied to other temperate ecological regions worldwide, especially the broadleaved ones.
Biogeoclimatic ecosystem classification (BEC) is an ecological classification framework used in British Columbia to define, describe, and map ecosystem-based units at various scales, from broad, ecologically-based climatic regions down to local ecosystems or sites. BEC is termed an ecosystem classification as the approach integrates site, soil, and vegetation characteristics to develop and characterize all units. BEC has a strong application focus and guides to classification and management of forests, grasslands and wetlands are available for much of the province to aid in identification of the ecosystem units.
Protea scorzonerifolia, the channel-leaf sugarbush, is a flower-bearing shrub belonging to the genus Protea. The plant is endemic to South Africa and occurs in the Du Toit's Kloof, Franschhoek and Groot-Winterhoek mountains. The plant became extinct on the Cape Peninsula.