Centrarchidae, better known as sunfishes, is a family of freshwater ray-finned fish belonging to the order Perciformes, native only to North America. There are eight universally included genera within the centrarchid family: Lepomis, Micropterus, Pomoxis (crappies), Enneacanthus, Centrarchus, Archoplites, Ambloplites, and Acantharchus. A genetic study in 2012 suggests that the highly distinct pygmy sunfishes of the genus Elassoma are also centrarchids.
An invasive or alien species is an introduced species to an environment that becomes overpopulated and harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native species that become harmful to their native environment after human alterations to its food web – for example, the purple sea urchin which has decimated kelp forests along the northern California coast due to overharvesting of its natural predator, the California sea otter. Since the 20th century, invasive species have become a serious economic, social, and environmental threat worldwide.
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there by human activity, directly or indirectly, and either deliberately or accidentally. Non-native species can have various effects on the local ecosystem. Introduced species that become established and spread beyond the place of introduction are considered naturalized. The process of human-caused introduction is distinguished from biological colonization, in which species spread to new areas through "natural" (non-human) means such as storms and rafting. The Latin expression neobiota captures the characteristic that these species are new biota to their environment in terms of established biological network relationships. Neobiota can further be divided into neozoa and neophyta (plants).
Pinus pinaster, the maritime pine or cluster pine, is a pine native to the south Atlantic Europe region and parts of the western Mediterranean. It is a hard, fast growing pine bearing small seeds with large wings.
Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological processes that slowly alter the layout of the physical environment, and human activity such as land conversion, which can alter the environment much faster and causes the extinction of many species. More specifically, habitat fragmentation is a process by which large and contiguous habitats get divided into smaller, isolated patches of habitats.
Realized niche width is a phrase relating to ecology, is defined by the actual space that an organism inhabits and the resources it can access as a result of limiting pressures from other species. An organism's ecological niche is determined by the biotic and abiotic factors that make up that specific ecosystem that allow that specific organism to survive there. The width of an organism's niche is set by the range of conditions a species is able to survive in that specific environment.
Habitat destruction is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby reducing biodiversity and species abundance. Habitat destruction is the leading cause of biodiversity loss. Fragmentation and loss of habitat have become one of the most important topics of research in ecology as they are major threats to the survival of endangered species.
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.
Naturalisation is the ecological phenomenon through which a species, taxon, or population of exotic origin integrates into a given ecosystem, becoming capable of reproducing and growing in it, and proceeds to disseminate spontaneously. In some instances, the presence of a species in a given ecosystem is so ancient that it cannot be presupposed whether it is native or introduced.
Ecological extinction is "the reduction of a species to such low abundance that, although it is still present in the community, it no longer interacts significantly with other species".
Grasses are one of the most abundant floras on all continents, except Antarctica. Their divergence is estimated to have taken place 200 million years ago. Humans have intentionally and unintentionally introduced these species to North America through travel and trade. On the North American plains, prairies, grasslands, and meadows at least 11% of grasses are non-native. North America is considered a hotspot for many invasive species of grasses, which threatens all of the endangered native grass species and potentially threatens other grass species. Conservation tactics and management policies can help prevent invasive species from taking over and driving native North American plants to extinction.
Phragmites australis, known as the common reed, is a species of flowering plant in the grass family Poaceae. It is a wetland grass that can grow up to 20 feet tall and has a cosmopolitan distribution worldwide.
The history of life on Earth is closely associated with environmental change on multiple spatial and temporal scales. Climate change is a long-term change in the average weather patterns that have come to define Earth’s local, regional and global climates. These changes have a broad range of observed effects that are synonymous with the term. Climate change is any significant long term change in the expected pattern, whether due to natural variability or as a result of human activity. Predicting the effects that climate change will have on plant biodiversity can be achieved using various models, however bioclimatic models are most commonly used.
Climate change has adversely affected terrestrial and marine ecosystems, including tundras, mangroves, coral reefs, and caves. Increasing global temperature, more frequent occurrence of extreme weather, and rising sea level are examples of the most impactful effects of climate change. Possible consequences of these effects include species decline and extinction, change within ecosystems, increased prevalence of invasive species, forests converting from carbon sinks to carbon sources, ocean acidification, disruption of the water cycle, and increased occurrence of natural disasters.
The effects of climate change in Saskatchewan are now being observed in parts of the province. There is evidence of reduction of biomass in Saskatchewan's boreal forests that is linked by researchers to drought-related water stress stemming from global warming, most likely caused by greenhouse gas emissions. While studies, as early as 1988 have shown that climate change will affect agriculture, whether the effects can be mitigated through adaptations of cultivars, or crops, is less clear. Resiliency of ecosystems may decline with large changes in temperature. The provincial government has responded to the threat of climate change by introducing a plan to reduce carbon emissions, "The Saskatchewan Energy and Climate Change Plan", in June 2007.
Privets are any of a number of shrubs or trees in the genus Ligustrum, many of which are invasive. The genus contains about 50 species native to the Old World and Australasia. Many members of the genus are grown as ornamental plants in parts of the world.
Biodiversity loss includes the worldwide extinction of different species, as well as the local reduction or loss of species in a certain habitat, resulting in a loss of biological diversity. The latter phenomenon can be temporary or permanent, depending on whether the environmental degradation that leads to the loss is reversible through ecological restoration/ecological resilience or effectively permanent. The current global extinction, has resulted in a biodiversity crisis being driven by human activities which push beyond the planetary boundaries and so far has proven irreversible.
Alien species, or species that are not native, invade habitats and alter ecosystems around the world. Invasive species are only considered invasive if they are able to survive and sustain themselves in their new environment. A habitat and the environment around it has natural flaws that make them vulnerable to invasive species. The level of vulnerability of a habitat to invasions from outside species is defined as its invasibility. One must be careful not to get this confused with invasiveness, which relates to the species itself and its ability to invade an ecosystem.
Climate change and invasive species refers to the process of the environmental destabilization caused by climate change. This environmental change facilitates the spread of invasive species — species that are not historically found in a certain region, and often bring about a negative impact to that region's native species.
Disease ecology is a sub-discipline of ecology concerned with the mechanisms, patterns, and effects of host-pathogen interactions, particularly those of infectious diseases. For example, it examines how parasites spread through and influence wildlife populations and communities. By studying the flow of diseases within the natural environment, scientists seek to better understand how changes within our environment can shape how pathogens, and other diseases, travel. Therefore, diseases ecology seeks to understand the links between ecological interactions and disease evolution. New emerging and re-emerging infectious diseases are increasing at unprecedented rates which can have lasting impacts on public health, ecosystem health, and biodiversity.
