Moussab/ORKG-training-evaluation-set huggingface dataset:
Research field: Ecology and Evolutionary Biology
Title: Exotic and native vegetation establishment following channelization of a western Iberian river
Abstract: Channelization is often a major cause of human impacts on river systems. It affects both hydrogeomorphic features and habitat characteristics and potentially impacts riverine flora and fauna. Human-disturbed fluvial ecosystems also appear to be particularly vulnerable to exotic plant establishment. Following a 12-year recovery period, the distribution, composition and cover of both exotic and native plant species were studied along a Portuguese lowland river segment, which had been subjected to resectioning, straightening and two-stage bank reinforcement, and were compared with those of a nearby, less impacted segment. The species distribution was also related to environmental data. Species richness and floristic composition in the channelized river segment were found to be similar to those at the more ‘natural’ river sites. Floral differences were primarily consistent with the dominance of cover by certain species. However, there were significant differences in exotic and native species richness and cover between the ‘natural’ corridor and the channelized segment, which was more susceptible to invasion by exotic perennial taxa, such as Eryngium pandanifolium, Paspalum paspalodes, Tradescantia fluminensis and Acacia dealbata. Factorial and canonical correspondence analyses revealed considerable patchiness in the distribution of species assemblages. The latter were associated with small differences in substrate composition and their own relative position across the banks and along the river segments in question. Data was also subjected to an unweighted pair-group arithmetic average clustering, and the Indicator Value methodology was applied to selected cluster noda in order to obtain significant indicator species. Copyright © 2001 John Wiley & Sons, Ltd.
Extracted statement — Study date: 2001
Research field: Ecology and Evolutionary Biology
Title: Control of plant species diversity and community invasibility by species immigration: seed richness versus seed density
Abstract: Brown, R. L. and Fridley, J. D. 2003. Control of plant species diversity andcommunity invasibility by species immigration: seed richness versus seed density. –Oikos 102: 15–24.Immigration rates of species into communities are widely understood to inﬂuencecommunity diversity, which in turn is widely expected to inﬂuence the susceptibilityof ecosystems to species invasion. For a given community, however, immigrationprocesses may impact diversity by means of two separable components: the numberof species represented in seed inputs and the density of seed per species. Theindependent effects of these components on plant species diversity and consequentrates of invasion are poorly understood. We constructed experimental plant commu-nities through repeated seed additions to independently measure the effects of seedrichness and seed density on the trajectory of species diversity during the develop-ment of annual plant communities. Because we sowed species not found in theimmediate study area, we were able to assess the invasibility of the resultingcommunities by recording the rate of establishment of species from adjacent vegeta-tion. Early in community development when species only weakly interacted, seedrichness had a strong effect on community diversity whereas seed density had littleeffect. After the plants became established, the effect of seed richness on measureddiversity strongly depended on seed density, and disappeared at the highest level ofseed density. The ability of surrounding vegetation to invade the experimentalcommunities was decreased by seed density but not by seed richness, primarilybecause the individual effects of a few sown species could explain the observedinvasion rates. These results suggest that seed density is just as important as seedrichness in the control of species diversity, and perhaps a more important determi-nant of community invasibility than seed richness in dynamic plant assemblages.
Extracted statement — Study date: 2003
Research field: Ecology and Evolutionary Biology
Title: The portability of foodweb dynamics: reassembling na Australian eucalypt-psyllid-bird association within California
Abstract: Aims. To evaluate the role of native predators (birds) within an Australian foodweb (lerp psyllids and eucalyptus trees) reassembled in California. Location. Eucalyptus groves within Santa Cruz, California. Methods. We compared bird diversity and abundance between a eucalyptus grove infested with lerp psyllids and a grove that was uninfested, using point counts. We documented shifts in the foraging behaviour of birds between the groves using structured behavioural observations. Additionally, we judged the effect of bird foraging on lerp psyllid abundance using exclosure experiments. Results. We found a greater richness and abundance of Californian birds within a psyllid infested eucalyptus grove compared to a matched non-infested grove, and that Californian birds modify their foraging behaviour within the infested grove in order to concentrate on ingesting psyllids. This suggests that Californian birds could provide indirect top-down benefits to eucalyptus trees similar to those observed in Australia. However, using bird exclosure experiments, we found no evidence of top-down control of lerp psyllids by Californian birds. Main conclusions. We suggest that physiological and foraging differences between Californian and Australian pysllid-eating birds account for the failure to observe top-down control of psyllid populations in California. The increasing rate of non-indigenous species invasions has produced local biotas that are almost entirely composed of non-indigenous species. This example illustrates the complex nature of cosmopolitan native-exotic food webs, and the ecological insights obtainable through their study. © 2004 Blackwell Publishing Ltd.
Extracted statement — Study date: 2004
Research field: Ecology and Evolutionary Biology
Title: Effects of an intense prescribed fire on understory vegetation in a mixed conifer forest
Abstract: Abstract Huisinga, K. D., D. C. Laughlin, P. Z. Fulé, J. D. Springer, and C. M. McGlone (Ecological Restoration Institute and School of Forestry, Northern Arizona University, Box 15017, Flagstaff, AZ 86011). Effects of an intense prescribed fire on understory vegetation in a mixed conifer forest. J. Torrey Bot. Soc. 132: 590–601. 2005.—Intense prescribed fire has been suggested as a possible method for forest restoration in mixed conifer forests. In 1993, a prescribed fire in a dense, never-harvested forest on the North Rim of Grand Canyon National Park escaped prescription and burned with greater intensity and severity than expected. We sampled this burned area and an adjacent unburned area to assess fire effects on understory species composition, diversity, and plant cover. The unburned area was sampled in 1998 and the burned area in 1999; 25% of the plots were resampled in 2001 to ensure that differences between sites were consistent and persistent, and not due to inter-annual climatic differences. Species composition differed significantly between unburned and burned sites; eight species were identified as indicators of the unburned site and thirteen as indicators of the burned site. Plant cover was nearly twice as great in the burned site than in the unburned site in the first years of measurement and was 4.6 times greater in the burned site in 2001. Average and total species richness was greater in the burned site, explained mostly by higher numbers of native annual and biennial forbs. Overstory canopy cover and duff depth were significantly lower in the burned site, and there were significant inverse relationships between these variables and plant species richness and plant cover. Greater than 95% of the species in the post-fire community were native and exotic plant cover never exceeded 1%, in contrast with other northern Arizona forests that were dominated by exotic species following high-severity fires. This difference is attributed to the minimal anthropogenic disturbance history (no logging, minimal grazing) of forests in the national park, and suggests that park managers may have more options than non-park managers to use intense fire as a tool for forest conservation and restoration.
Extracted statement — Study date: 2005
Research field: Ecology and Evolutionary Biology
Title: Comprehensive review of the records of the biota of the Indian Seas and introduction of non-indigenous species
Abstract: 1. Comparison of the pre-1960 faunal survey data for the Indian Seas with that for the post-1960 period showed that 205 non-indigenous taxa were introduced in the post-1960 period; shipping activity is considered a plausible major vector for many of these introductions. 2. Of the non-indigenous taxa, 21% were fish, followed by Polychaeta (<11%), Algae (10%), Crustacea (10%), Mollusca (10%), Ciliata (8%), Fungi (7%), Ascidians (6%) and minor invertebrates (17%). 3. An analysis of the data suggests a correspondence between the shipping routes between India and various regions. There were 75 species common to the Indian Seas and the coastal seas of China and Japan, 63 to the Indo-Malaysian region, 42 to the Mediterranean, 40 and 34 to western and eastern Atlantic respectively, and 41 to Australia and New Zealand. A further 33 species were common to the Caribbean region, 32 to the eastern Pacific, 14 and 24 to the west and east coasts of Africa respectively, 18 to the Baltic, 15 to the middle Arabian Gulf and Red Sea, and 10 to the Brazilian coast. 4. The Indo-Malaysian region can be identified as a centre of xenodiversity for biota from Southeast Asia, China, Japan, Philippines and Australian regions. 5. Of the introduced species, the bivalve Mytilopsis sallei and the serpulid Ficopomatus enigmaticus have become pests in the Indian Seas, consistent with the Williamson and Fitter ‘tens rule’. Included amongst the biota with economic impact are nine fouling and six wood-destroying organisms. 6. Novel occurrences of the human pathogenic vibrios, e.g. Vibrio parahaemolyticus, non-01 Vibrio cholerae, Vibrio vulnificus and Vibrio mimicus and the harmful algal bloom species Alexandrium spp. and Gymnodinium nagasakiense in the Indian coastal waters could be attributed to ballast water introductions. 7. Introductions of alien biota could pose a threat to the highly productive tropical coastal waters, estuaries and mariculture sites and could cause economic impacts and ecological surprises. 8. In addition to strict enforcement of a national quarantine policy on ballast water discharges, long-term multidisciplinary research on ballast water invaders is crucial to enhance our understanding of the biodiversity and functioning of the ecosystem. Copyright © 2005 John Wiley & Sons, Ltd.
Extracted statement — Study date: 2005
Research field: Ecology and Evolutionary Biology
Title: The demography of introduction pathways, propagule pressure and occurrences of non-native freshwater fish in England
Abstract: 1. Biological invasion theory predicts that the introduction and establishment of non-native species is positively correlated with propagule pressure. Releases of pet and aquarium fishes to inland waters has a long history; however, few studies have examined the demographic basis of their importation and incidence in the wild. 2. For the 1500 grid squares (10×10 km) that make up England, data on human demographics (population density, numbers of pet shops, garden centres and fish farms), the numbers of non-native freshwater fishes (from consented licences) imported in those grid squares (i.e. propagule pressure), and the reported incidences (in a national database) of non-native fishes in the wild were used to examine spatial relationships between the occurrence of non-native fishes and the demographic factors associated with propagule pressure, as well as to test whether the demographic factors are statistically reliable predictors of the incidence of non-native fishes, and as such surrogate estimators of propagule pressure. 3. Principal coordinates of neighbour matrices analyses, used to generate spatially explicit models, and confirmatory factor analysis revealed that spatial distributions of non-native species in England were significantly related to human population density, garden centre density and fish farm density. Human population density and the number of fish imports were identified as the best predictors of propagule pressure. 4. Human population density is an effective surrogate estimator of non-native fish propagule pressure and can be used to predict likely areas of non-native fish introductions. In conjunction with fish movements, where available, human population densities can be used to support biological invasion monitoring programmes across Europe (and perhaps globally) and to inform management decisions as regards the prioritization of areas for the control of non-native fish introductions. © Crown copyright 2010. Reproduced with the permission of her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Extracted statement — Study date: 2010
Research field: Ecology and Evolutionary Biology
Title: Identification of alien predators that should not be removed for controlling invasive crayfish threatening endangered odonates
Abstract: 1. When multiple invasive species coexist in the same ecosystem and their diets change as they grow, determining whether to eradicate any particular invader is difficult because of complex predator–prey interactions. 2. A stable isotope food-web analysis was conducted to explore an appropriate management strategy for three potential alien predators (snakehead Channa argus, bullfrog Rana catesbeiana, red-eared slider turtle Trachemys scripta elegans) of invasive crayfish Procambarus clarkii that had severely reduced the densities of endangered odonates in a pond in Japan. 3. The stable isotope analysis demonstrated that medium- and small-sized snakeheads primarily depended on crayfish and stone moroko Pseudorasbora parva. Both adult and juvenile bullfrogs depended on terrestrial arthropods, and juveniles exhibited a moderate dependence on crayfish. The turtle showed little dependence on crayfish. 4. These results suggest that eradication of snakeheads risks the possibility of mesopredator release, while such risk appears to be low in other alien predators. Copyright © 2011 John Wiley & Sons, Ltd.
Extracted statement — Study date: 2011
Research field: Ecology and Evolutionary Biology
Title: Seedling defoliation, plant growth and flowering potential in native- and invasive-range Plantago lanceolata populations
Abstract: Hanley ME (2012). Seedling defoliation, plant growth and flowering potential in native- and invasive-range Plantago lanceolata populations. Weed Research52, 252–259. Summary The plastic response of weeds to new environmental conditions, in particular the likely relaxation of herbivore pressure, is considered vital for successful colonisation and spread. However, while variation in plant anti-herbivore resistance between native- and introduced-range populations is well studied, few authors have considered herbivore tolerance, especially at the seedling stage. This study examines variation in seedling tolerance in native (European) and introduced (North American) Plantago lanceolata populations following cotyledon removal at 14 days old. Subsequent effects on plant growth were quantified at 35 days, along with effects on flowering potential at maturity. Cotyledon removal reduced early growth for all populations, with no variation between introduced- or native-range plants. Although more variable, the effects of cotyledon loss on flowering potential were also unrelated to range. The likelihood that generalist seedling herbivores are common throughout North America may explain why no difference in seedling tolerance was apparent. However, increased flowering potential in plants from North American P. lanceolata populations was observed. As increased flowering potential was not lost, even after severe cotyledon damage, the manifestation of phenotypic plasticity in weeds at maturity may nonetheless still be shaped by plasticity in the ability to tolerate herbivory during seedling establishment.
Extracted statement — Study date: 2012
Research field: Ecology and Evolutionary Biology
Title: Germination patterns and implications for invasiveness in three Taraxacum (Asteraceae) species
Abstract: Luo J & Cardina J (2012). Germination patterns and implications for invasiveness in three Taraxacum (Asteraceae) species. Weed Research 52, 112–121. Summary The ability to germinate across different environments has been considered an important trait of invasive plant species that allows for establishment success in new habitats. Using two alien congener species of Asteraceae –Taraxacum officinale (invasive) and Taraxacum laevigatum laevigatum (non-invasive) – we tested the hypothesis that invasive species germinate better than non-invasives under various conditions. The germination patterns of Taraxacum brevicorniculatum, a contaminant found in seeds of the crop Taraxacum kok-saghyz, were also investigated to evaluate its invasive potential. In four experiments, we germinated seeds along gradients of alternating temperature, constant temperature (with or without light), water potential and following accelerated ageing. Neither higher nor lower germination per se explained invasion success for the Taraxacum species tested here. At alternating temperature, the invasive T. officinale had higher germination than or similar to the non-invasive T. laevigatum. Contrary to predictions, T. laevigatum exhibited higher germination than T. officinale in environments of darkness, low water potential or after the seeds were exposed to an ageing process. These results suggested a complicated role of germination in the success of T. officinale. Taraxacum brevicorniculatum showed the highest germination among the three species in all environments. The invasive potential of this species is thus unclear and will probably depend on its performance at other life stages along environmental gradients.
Extracted statement — Study date: 2012
Research field: Ecology and Evolutionary Biology
Title: Phenotypic variation of an alien species in a new environment: the body size and diet of American mink over time and at local and continental scales
Abstract: Introduced species must adapt their ecology, behaviour, and morphological traits to new conditions. The successful introduction and invasive potential of a species are related to its levels of phenotypic plasticity and genetic polymorphism. We analysed changes in the body mass and length of American mink (Neovison vison) since its introduction into the Warta Mouth National Park, western Poland, in relation to diet composition and colonization progress from 1996 to 2004. Mink body mass decreased significantly during the period of population establishment within the study area, with an average decrease of 13% from 1.36 to 1.18 kg in males and of 16% from 0.83 to 0.70 kg in females. Diet composition varied seasonally and between consecutive years. The main prey items were mammals and fish in the cold season and birds and fish in the warm season. During the study period the proportion of mammals preyed upon increased in the cold season and decreased in the warm season. The proportion of birds preyed upon decreased over the study period, whereas the proportion of fish increased. Following introduction, the strictly aquatic portion of mink diet (fish and frogs) increased over time, whereas the proportion of large prey (large birds, muskrats, and water voles) decreased. The average yearly proportion of large prey and average-sized prey in the mink diet was significantly correlated with the mean body masses of males and females. Biogeographical variation in the body mass and length of mink was best explained by the percentage of large prey in the mink diet in both sexes, and by latitude for females. Together these results demonstrate that American mink rapidly changed their body mass in relation to local conditions. This phenotypic variability may be underpinned by phenotypic plasticity and/or by adaptation of quantitative genetic variation. The potential to rapidly change phenotypic variation in this manner is an important factor determining the negative ecological impacts of invasive species. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 681–693.
Extracted statement — Study date: 2012
Research field: Ecology and Evolutionary Biology
Title: Alien aquatic plant species in European countries
Abstract: Hussner A (2012). Alien aquatic plant species in European countries. Weed Research52, 297–306. Summary Alien aquatic plant species cause serious ecological and economic impacts to European freshwater ecosystems. This study presents a comprehensive overview of all alien aquatic plants in Europe, their places of origin and their distribution within the 46 European countries. In total, 96 aquatic species from 30 families have been reported as aliens from at least one European country. Most alien aquatic plants are native to Northern America, followed by Asia and Southern America. Elodea canadensis is the most widespread alien aquatic plant in Europe, reported from 41 European countries. Azolla filiculoides ranks second (25), followed by Vallisneria spiralis (22) and Elodea nuttallii (20). The highest number of alien aquatic plant species has been found in Italy and France (34 species), followed by Germany (27), Belgium and Hungary (both 26) and the Netherlands (24). Even though the number of alien aquatic plants seems relatively small, the European and Mediterranean Plant Protection Organization (EPPO, http://www.eppo.org) has listed 18 of these species as invasive or potentially invasive within the EPPO region. As ornamental trade has been regarded as the major pathway for the introduction of alien aquatic plants, trading bans seem to be the most effective option to reduce the risk of further unintended entry of alien aquatic plants into Europe.
Extracted statement — Study date: 2012
Research field: Ecology and Evolutionary Biology
Title: A phylogenetic approach towards understanding the drivers of plant invasiveness on Robben Island- South Africa
Abstract: Invasive plant species are a considerable threat to ecosystems globally and on islands in particular where species diversity can be relatively low. In this study, we examined the phylogenetic basis of invasion success on Robben Island in South Africa. The flora of the island was sampled extensively and the phylogeny of the local community was reconstructed using the two core DNA barcode regions, rbcLa and matK. By analysing the phylogenetic patterns of native and invasive floras at two different scales, we found that invasive alien species are more distantly related to native species, a confirmation of Darwin's naturalization hypothesis. However, this pattern also holds even for randomly generated communities, therefore discounting the explanatory power of Darwin's naturalization hypothesis as the unique driver of invasion success on the island. These findings suggest that the drivers of invasion success on the island may be linked to species traits rather than their evolutionary history alone, or to the combination thereof. This result also has implications for the invasion management programmes currently being implemented to rehabilitate the native diversity on Robben Island. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172, 142–152.
Extracted statement — Study date: 2013