![Secondary succession in overgrazed Pannonian sandy](http://s1.studyres.com/store/data/001693216_1-872b06926081238dab87f6a85494e4f4-300x300.png)
Secondary succession in overgrazed Pannonian sandy
... Thomas & Dale 1976), but only a few studies evaluate the role of microtopography on annual-perennial dynamics (e.g., Pemadasa et al. 1974). Sandy grasslands, like many other types of grassland in the Pannonian region have undergone major compositional changes during the last few decades due to chang ...
... Thomas & Dale 1976), but only a few studies evaluate the role of microtopography on annual-perennial dynamics (e.g., Pemadasa et al. 1974). Sandy grasslands, like many other types of grassland in the Pannonian region have undergone major compositional changes during the last few decades due to chang ...
Figs and the Diversity of Tropical Rainforests
... large number of traits, implying that they should have similar ecologies and thus exhibit a large degree of niche overlap. The coexistence of suites of such ecologically similar species is a special problem for the diversity of tropical rainforests, because standard niche theory predicts the competi ...
... large number of traits, implying that they should have similar ecologies and thus exhibit a large degree of niche overlap. The coexistence of suites of such ecologically similar species is a special problem for the diversity of tropical rainforests, because standard niche theory predicts the competi ...
Interspecific competition and predation in American carnivore families
... Seventy-seven species of terrestrial American carnivores, belonging to six families (Canidae, Felidae, Mephitidae, Mustelidae, Procyonidae and Ursidae) were included in our analyses. Marine otters were excluded because the majority of their intraguild interactions are with marine taxa not included i ...
... Seventy-seven species of terrestrial American carnivores, belonging to six families (Canidae, Felidae, Mephitidae, Mustelidae, Procyonidae and Ursidae) were included in our analyses. Marine otters were excluded because the majority of their intraguild interactions are with marine taxa not included i ...
Comparative Analysis of Diversity and Similarity Indices with Special
... to calculate the expected maximum value of the indices to which the observed values can be related at any combination of sample sizes at the experimental sites. This paper examines the effects of sample size and diversity on the expected values of diversity indices and similarity indices, using vari ...
... to calculate the expected maximum value of the indices to which the observed values can be related at any combination of sample sizes at the experimental sites. This paper examines the effects of sample size and diversity on the expected values of diversity indices and similarity indices, using vari ...
The niche, biogeography and species interactions
... By definition, species generally cannot spread outside of their ecological niche, the set of conditions where they can persist (potentially including both abiotic and biotic factors). Therefore, most so-called ‘geographic barriers’ and ‘physical barriers’ (e.g. oceans, rivers and mountains) are simp ...
... By definition, species generally cannot spread outside of their ecological niche, the set of conditions where they can persist (potentially including both abiotic and biotic factors). Therefore, most so-called ‘geographic barriers’ and ‘physical barriers’ (e.g. oceans, rivers and mountains) are simp ...
FACTORS AFFECTING IMPLEMENTATION OF RECOVERY PLANS
... implemented, underway, completed), which were available for 176 of the 181 species. Precise dates of implementation for each task were unavailable. For each species, the percentage of implemented recovery tasks was calculated by dividing the number of tasks that were underway or completed by the tot ...
... implemented, underway, completed), which were available for 176 of the 181 species. Precise dates of implementation for each task were unavailable. For each species, the percentage of implemented recovery tasks was calculated by dividing the number of tasks that were underway or completed by the tot ...
Oecologia (1994) 97:326-332 Springer-Verlag 1994 ORIGINAL PAPER
... in Fig. 1. The natural history of the lizard is given by Daniel (1960) and Harris (1964) and the effects of the parasites on rainbow lizards are presented by Schall (1990b). Both parasites are common in A. agama in Sierra Leone and are the only known malarial species infecting the lizards. We collec ...
... in Fig. 1. The natural history of the lizard is given by Daniel (1960) and Harris (1964) and the effects of the parasites on rainbow lizards are presented by Schall (1990b). Both parasites are common in A. agama in Sierra Leone and are the only known malarial species infecting the lizards. We collec ...
Habitat suitability modelling and niche theory
... the response curves of more than 1000 plants, found that long gradients and narrow niches increased the frequency of symmetric bell-shaped responses. Skewness, although slightly favoured by the optima for a species being near extremes of gradient, was rather uncommon. Interactions between variables ...
... the response curves of more than 1000 plants, found that long gradients and narrow niches increased the frequency of symmetric bell-shaped responses. Skewness, although slightly favoured by the optima for a species being near extremes of gradient, was rather uncommon. Interactions between variables ...
Role and consequences of fish diversity in the functioning of African
... selection, ontogenic shift) has been fairly well documented by various studies of African fish. They are also challenging subjects for studies of resource partitioning, a well documented example being given by zooplanktivores in Lake Turkana. The principle of cascading trophic interactions has been ...
... selection, ontogenic shift) has been fairly well documented by various studies of African fish. They are also challenging subjects for studies of resource partitioning, a well documented example being given by zooplanktivores in Lake Turkana. The principle of cascading trophic interactions has been ...
Smooth sumac (Rhus glabra) Staghorn sumac (Rhus typhina)
... Sumac is native throughout eastern U.S. and southern Canada but occurs most commonly in eastern U.S. on forest edges, abandoned fields and roadsides. Their interesting branching patterns, height, bright-red fall foliage and colony forming habit make these woody perennial shrubs of the cashew family ...
... Sumac is native throughout eastern U.S. and southern Canada but occurs most commonly in eastern U.S. on forest edges, abandoned fields and roadsides. Their interesting branching patterns, height, bright-red fall foliage and colony forming habit make these woody perennial shrubs of the cashew family ...
REVIEW ARTICLE A research strategy for
... Biodiversity and Conservation (e.g. Liu et al. 2011). These sources revealed two reviews of particular relevance: an account of 100 questions of importance to the conservation of global biodiversity (Sutherland et al. 2009) and key research questions identified to manage non-indigenous species (Byer ...
... Biodiversity and Conservation (e.g. Liu et al. 2011). These sources revealed two reviews of particular relevance: an account of 100 questions of importance to the conservation of global biodiversity (Sutherland et al. 2009) and key research questions identified to manage non-indigenous species (Byer ...
ppt
... Phylogenetic Perspectives Webb (2000) An example from rainforest trees: Is the distribution of species among habitats (or samples) in a community nonrandom with respect to phylogeny? “The demonstration of nonrandom spatial association of species with habitats is a necessary but not sufficient criter ...
... Phylogenetic Perspectives Webb (2000) An example from rainforest trees: Is the distribution of species among habitats (or samples) in a community nonrandom with respect to phylogeny? “The demonstration of nonrandom spatial association of species with habitats is a necessary but not sufficient criter ...
Long-term dynamics of biotic and abiotic resistance to exotic species
... reveal the relative importance of factors that directly influence population dynamics. We observed that, in general, exotic species were strongly and negatively affected by the relatively harsh abiotic conditions associated with pool inundation during the winter wet phase. Most exotic species were un ...
... reveal the relative importance of factors that directly influence population dynamics. We observed that, in general, exotic species were strongly and negatively affected by the relatively harsh abiotic conditions associated with pool inundation during the winter wet phase. Most exotic species were un ...
Exotic Species, Naturalisation, and Biological Nativism
... Park from the west, they be treated as welcome natives because these goats come from a population not established by humans (Wagner 1995: 10). Or consider the wild pigs (Sus scrofa) in the Hawaiian rainforest, whose ancestors were brought to Hawaii by Polynesians perhaps 1500 years ago.1 Are they st ...
... Park from the west, they be treated as welcome natives because these goats come from a population not established by humans (Wagner 1995: 10). Or consider the wild pigs (Sus scrofa) in the Hawaiian rainforest, whose ancestors were brought to Hawaii by Polynesians perhaps 1500 years ago.1 Are they st ...
Floristics and Distribution Patterns of Lichens and Bryophytes in
... Despite the rich diversity of bryophytes and lichens in the semiarid interior of British Columbia, our understanding of its flora and ecology is rudimentary. McIntosh (1986, 1997) conducted the most complete survey of the bryophytes of British Columbia’s grasslands in a thesis that included a key to ...
... Despite the rich diversity of bryophytes and lichens in the semiarid interior of British Columbia, our understanding of its flora and ecology is rudimentary. McIntosh (1986, 1997) conducted the most complete survey of the bryophytes of British Columbia’s grasslands in a thesis that included a key to ...
Interspecific competition in metapopulations
... metapopulation dynamics and species distributions have been evaluated. As far as I know, the best studied system is the three waterflea (Daphnia) species in rockpools in Fennoscandia. Rockpools are small, waterfilled depressions in the bedrock containing fresh or brackish water. The habitat is commo ...
... metapopulation dynamics and species distributions have been evaluated. As far as I know, the best studied system is the three waterflea (Daphnia) species in rockpools in Fennoscandia. Rockpools are small, waterfilled depressions in the bedrock containing fresh or brackish water. The habitat is commo ...
Non volant mammals of Dawesville-Binningup
... fauna of the northern Swan Coastal Plain between the Swan and Moore Rivers and evaluated the impact of the first 150 years of European settlement on the indigenous fauna. That study concluded that the impact of settlement had been most pronounced on the mammalian fauna. Reviewing all available data, ...
... fauna of the northern Swan Coastal Plain between the Swan and Moore Rivers and evaluated the impact of the first 150 years of European settlement on the indigenous fauna. That study concluded that the impact of settlement had been most pronounced on the mammalian fauna. Reviewing all available data, ...
insight review articles - Montana State University
... number of ways in which ranges can be distributed changes systematically between the bounds. Thus, whereas species with latitudinal midpoints midway between the bounds can extend a little or a long way before those bounds are encountered, those with midpoints close to the bounds can extend only a li ...
... number of ways in which ranges can be distributed changes systematically between the bounds. Thus, whereas species with latitudinal midpoints midway between the bounds can extend a little or a long way before those bounds are encountered, those with midpoints close to the bounds can extend only a li ...
Biodiversity and Species Extinctions in Model Food Webs Charlotte Borrvall
... seriously affected by environmental stochasticity than species-poor ones in that per species risk of extinction, within a given period of time, increases with increasing species richness. These results are in contrast to expectations that biodiversity could help communities to cope with environmenta ...
... seriously affected by environmental stochasticity than species-poor ones in that per species risk of extinction, within a given period of time, increases with increasing species richness. These results are in contrast to expectations that biodiversity could help communities to cope with environmenta ...
Understanding Our Environment
... Wildlife smuggling is very profitable. - Leopard fur / Rhinoceros horns US Annual pet trade in wild species: 2 million reptiles 1 million amphibians and mammals 500,000 birds 128,000 tropical fish (often caught with cyanide above coral reefs) Cunningham - Cunningham - Saigo: Environmenta ...
... Wildlife smuggling is very profitable. - Leopard fur / Rhinoceros horns US Annual pet trade in wild species: 2 million reptiles 1 million amphibians and mammals 500,000 birds 128,000 tropical fish (often caught with cyanide above coral reefs) Cunningham - Cunningham - Saigo: Environmenta ...
Understanding Our Environment
... Wildlife smuggling is very profitable. - Leopard fur / Rhinoceros horns US Annual pet trade in wild species: 2 million reptiles 1 million amphibians and mammals 500,000 birds 128,000 tropical fish (often caught with cyanide above coral reefs) Cunningham - Cunningham - Saigo: Environmenta ...
... Wildlife smuggling is very profitable. - Leopard fur / Rhinoceros horns US Annual pet trade in wild species: 2 million reptiles 1 million amphibians and mammals 500,000 birds 128,000 tropical fish (often caught with cyanide above coral reefs) Cunningham - Cunningham - Saigo: Environmenta ...
Interspecific Competition in Plants: How Well Do Current Methods
... sequences of competition to its physiological and genetic basis, is very large. It is not the intention of this article to review these in detail. For a more comprehensive analysis of the classes of questions asked in interspecific plant competition research, see other recent reviews by Connell (198 ...
... sequences of competition to its physiological and genetic basis, is very large. It is not the intention of this article to review these in detail. For a more comprehensive analysis of the classes of questions asked in interspecific plant competition research, see other recent reviews by Connell (198 ...
Impacts of introduced predatory fishes in Ontario lakes: Assessing
... No difference in effect of native or introduced littoral predators on native minnow presence (Whittier et al. 1997) ...
... No difference in effect of native or introduced littoral predators on native minnow presence (Whittier et al. 1997) ...
Lake Manager`s Handbook: Alien Invaders
... they were first introduced into (see section 4). Alien fish species currently in New Zealand are mostly unable to spread between catchments naturally, unless they are tolerant of saltwater (for example, chinook salmon Oncorhynchus tshawytscha and brown trout Salmo trutta). The main mechanism of spre ...
... they were first introduced into (see section 4). Alien fish species currently in New Zealand are mostly unable to spread between catchments naturally, unless they are tolerant of saltwater (for example, chinook salmon Oncorhynchus tshawytscha and brown trout Salmo trutta). The main mechanism of spre ...
Introduced species
![](https://commons.wikimedia.org/wiki/Special:FilePath/Melilotus_alba_bgiu.jpg?width=300)
An introduced, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its native distributional range, which has arrived there by human activity, either deliberate or accidental. Non-native species can have various effects on the local ecosystem. Introduced species that become established and spread beyond the place of introduction are called invasive species. Some have a negative effect on a local ecosystem. Some introduced species may have no negative effect or only minor impact. Some species have been introduced intentionally to combat pests. They are called biocontrols and may be regarded as beneficial as an alternative to pesticides in agriculture for example. In some instances the potential for being beneficial or detrimental in the long run remains unknown. A list of some introduced species is given in a separate article.The effects of introduced species on natural environments have gained much scrutiny from scientists, governments, farmers and others.