WorldWideScience

Sample records for nonnative plant species

  1. Arthropod assemblages on native and nonnative plant species of a coastal reserve in California.

    Science.gov (United States)

    Fork, Susanne K

    2010-06-01

    Biological invasions by nonnative plant species are a widespread phenomenon. Many studies have shown strong ecological impacts of plant invasions on native plant communities and ecosystem processes. Far fewer studies have examined effects on associated animal communities. From the perspective of a reserve's land management, I addressed the question of whether arthropod assemblages on two nonnative plant species of concern were impoverished compared with those assemblages associated with two predominant native plant species of that reserve. If the nonnative plant species, Conium maculatum L., and Phalaris aquatica L., supported highly depauperate arthropod assemblages compared with the native plant species, Baccharis pilularis De Candolle and Leymus triticoides (Buckley) Pilger, this finding would provide additional support for prioritizing removal of nonnatives and restoration of natives. I assessed invertebrate assemblages at the taxonomic levels of arthropod orders, Coleoptera families, and Formicidae species, using univariate analyses to examine community attributes (richness and abundance) and multivariate techniques to assess arthropod assemblage community composition differences among plant species. Arthropod richness estimates by taxonomic level between native and nonnative vegetation showed varying results. Overall, arthropod richness of the selected nonnative plants, examined at higher taxonomic resolution, was not necessarily less diverse than two of common native plants found on the reserve, although differences were found among plant species. Impacts of certain nonnative plant species on arthropod assemblages may be more difficult to elucidate than those impacts shown on native plants and ecosystem processes.

  2. Effects of ecological restoration alternative treatments on nonnative plant species establishment

    Science.gov (United States)

    Michael T. Stoddard; Christopher M. McGlone; Peter Z. Fule

    2008-01-01

    Disturbances generated by forest restoration treatments have the potential for enhancing the establishment of nonnative species thereby impeding long-term native plant recovery. In a ponderosa pine forest next to the Fort Valley Experimental Forest, Arizona, we examined the establishment of nonnative species after three alternative treatments with different intensities...

  3. Periphyton density is similar on native and non-native plant species

    NARCIS (Netherlands)

    Grutters, B.M.C.; Gross, Elisabeth M.; van Donk, E.; Bakker, E.S.

    2017-01-01

    Non-native plants increasingly dominate the vegetation in aquatic ecosystems and thrive in eutrophic conditions. In eutrophic conditions, submerged plants risk being overgrown by epiphytic algae; however, if non-native plants are less susceptible to periphyton than natives, this would contribute to

  4. Presence and abundance of non-native plant species associated with recent energy development in the Williston Basin

    Science.gov (United States)

    Preston, Todd M.

    2015-01-01

    The Williston Basin, located in the Northern Great Plains, is experiencing rapid energy development with North Dakota and Montana being the epicenter of current and projected development in the USA. The average single-bore well pad is 5 acres with an estimated 58,485 wells in North Dakota alone. This landscape-level disturbance may provide a pathway for the establishment of non-native plants. To evaluate potential influences of energy development on the presence and abundance of non-native species, vegetation surveys were conducted at 30 oil well sites (14 ten-year-old and 16 five-year-old wells) and 14 control sites in native prairie environments across the Williston Basin. Non-native species richness and cover were recorded in four quadrats, located at equal distances, along four transects for a total of 16 quadrats per site. Non-natives were recorded at all 44 sites and ranged from 5 to 13 species, 7 to 15 species, and 2 to 8 species at the 10-year, 5-year, and control sites, respectively. Respective non-native cover ranged from 1 to 69, 16 to 76, and 2 to 82 %. Total, forb, and graminoid non-native species richness and non-native forb cover were significantly greater at oil well sites compared to control sites. At oil well sites, non-native species richness and forb cover were significantly greater adjacent to the well pads and decreased with distance to values similar to control sites. Finally, non-native species whose presence and/or abundance were significantly greater at oil well sites relative to control sites were identified to aid management efforts.

  5. The Spread of Non-native Plant Species Collection of Cibodas Botanical Garden into Mt. Gede Pangrango National Park

    Directory of Open Access Journals (Sweden)

    Musyarofah Zuhri

    2013-05-01

    Full Text Available The role of botanic garden in spread of non-native plant species has concerned of international worldwide. This study aimed to study the extent of non-native plant species from Cibodas Botanical Garden (CBG which invades into natural rainforest. A line transect was made edge-to-interior with 1,600 m in distance from CBG boundary. Result showed that distance from CBG was not significant in correlation with non-native tree and treelet density. Furthermore, presence of existing CBG’s plant collection was not a single aspect which influenced presence and abundance. Three invasive species possibly was escape from CBG and it showed edge-to-interior in stems density, i.e. Cinchona pubescens, Calliandra calothyrsus and Cestrum aurantiacum. The patterns of non-native species were influenced by presence of ditch across transect, existence of human trail, and the other non-native species did not have general pattern of spread distribution. Overall, botanical gardens should minimize the risk of unintentional introduced plant by perform site-specific risk assessment.

  6. The role of wildfire in the establishment and range expansion of nonnative plant species into natural areas: A review of current literature

    Science.gov (United States)

    Mara Johnson; Lisa J. Rew; Bruce D. Maxwell; Steve Sutherland

    2006-01-01

    Nonnative invasive plants are one of the greatest threats to natural ecosystems worldwide (Vitousek et al. 1996). In fact, their spread has been described as "a raging biological wildfire" (Dewey et al. 1995). Disturbances tend to create conditions that are favorable for germination and establishment of plant species. Nonnative plant species are often...

  7. Fleshy fruit removal and nutritional composition of winter-fruiting plants: a comparison of non-native invasive and native species

    Science.gov (United States)

    Cathryn H. Greenberg; Scott T. Walter

    2010-01-01

    Invasive, non-native plants threaten forest ecosystems by reducing native plant species richness and potentially altering ecosystem processes. Seed dispersal is critical for successful invasion and range expansion by non-native plants; dispersal is likely to be enhanced if they can successfully compete with native plants for disperser services. Fruit production by non-...

  8. Northward invading non-native vascular plant species in and adjacent to Wood Buffalo National Park

    Energy Technology Data Exchange (ETDEWEB)

    Wein, R.W.; Wein, G.; Bahret, S.; Cody, W.J. (Alberta University, Edmonton, AB (Canada). Canadian Circumpolar Institute)

    A survey of the non-native vascular plant species in Wood Buffalo National Park, Canada's largest forested National Park, documented their presence and abundance in key locations. Most of the fifty-four species (nine new records) were found in disturbed sites including roadsides, settlements, farms, areas of altered hydrological regimes, recent bums, and intensive bison grazing. Species that have increased most in geographic area and abundance in recent years include [ital Agropyron repens], [ital Bromus inermis], [ital Chenopodium album], [ital Melilotus spp.], [ital Trifolium spp.], [ital Plantago major], [ital Achillea millefolium], [ital Crepis tectorum] and [ital Sonchus arvensis]. An additional 20 species, now common in the Peace River and Fort Vermilion areas, have the potential to invade the Park if plant communities are subjected to additional stress as northern climates are modified by the greenhouse effect and as other human-caused activities disturb the vegetation. It is recommended that permanent plots be located in key locations and monitored for species invasion and changing abundances as input to management plans.

  9. Response of six non-native invasive plant species to wildfires in the northern Rocky Mountains, USA

    Science.gov (United States)

    Dennis E. Ferguson; Christine L. Craig

    2010-01-01

    This paper presents early results on the response of six non-native invasive plant species to eight wildfires on six National Forests (NFs) in the northern Rocky Mountains, USA. Stratified random sampling was used to choose 224 stands based on burn severity, habitat type series, slope steepness, stand height, and stand density. Data for this report are from 219 stands...

  10. Interactive influences of wildfire and nonnative species on plant community succession in Hawaii Volcanoes National Park.

    Science.gov (United States)

    Alison Ainsworth

    2007-01-01

    The role of fire as a natural disturbance, its interactions with nonnative species and effects of repeated fires in the Hawaiian Islands have received little investigation. We are unsure of the role fire played in shaping forest structure and composition as well as affecting evolutionary processes of the native biota. Yet, many species do have adaptations that...

  11. Genetically based differentiation in growth of multiple non-native plant species along a steep environmental gradient.

    Science.gov (United States)

    Haider, Sylvia; Kueffer, Christoph; Edwards, Peter J; Alexander, Jake M

    2012-09-01

    A non-native plant species spreading along an environmental gradient may need to adjust its growth to the prevailing conditions that it encounters by a combination of phenotypic plasticity and genetic adaptation. There have been several studies of how non-native species respond to changing environmental conditions along latitudinal gradients, but much less is known about elevational gradients. We conducted a climate chamber experiment to investigate plastic and genetically based growth responses of 13 herbaceous non-native plants along an elevational gradient from 100 to 2,000 m a.s.l. in Tenerife. Conditions in the field ranged from high anthropogenic disturbance but generally favourable temperatures for plant growth in the lower half of the gradient, to low disturbance but much cooler conditions in the upper half. We collected seed from low, mid and high elevations and grew them in climate chambers under the characteristic temperatures at these three elevations. Growth of all species was reduced under lower temperatures along both halves of the gradient. We found consistent genetically based differences in growth over the upper elevational gradient, with plants from high-elevation sites growing more slowly than those from mid-elevation ones, while the pattern in the lower part of the gradient was more mixed. Our data suggest that many non-native plants might respond to climate along elevational gradients by genetically based changes in key traits, especially at higher elevations where low temperatures probably impose a stronger selection pressure. At lower elevations, where anthropogenic influences are greater, higher gene flow and frequent disturbance might favour genotypes with broad ecological amplitudes. Thus the importance of evolutionary processes for invasion success is likely to be context-dependent.

  12. UV Screening in Native and Non-native Plant Species in the Tropical Alpine: Implications for Climate Change-Driven Migration of Species to Higher Elevations

    Directory of Open Access Journals (Sweden)

    Paul W. Barnes

    2017-08-01

    Full Text Available Ongoing changes in Earth’s climate are shifting the elevation ranges of many plant species with non-native species often experiencing greater expansion into higher elevations than native species. These climate change-induced shifts in distributions inevitably expose plants to novel biotic and abiotic environments, including altered solar ultraviolet (UV-B (280–315 nm radiation regimes. Do the greater migration potentials of non-native species into higher elevations imply that they have more effective UV-protective mechanisms than native species? In this study, we surveyed leaf epidermal UV-A transmittance (TUV A in a diversity of plant species representing different growth forms to test whether native and non-native species growing above 2800 m elevation on Mauna Kea, Hawaii differed in their UV screening capabilities. We further compared the degree to which TUV A varied along an elevation gradient in the native shrub Vaccinium reticulatum and the introduced forb Verbascum thapsus to evaluate whether these species differed in their abilities to adjust their levels of UV screening in response to elevation changes in UV-B. For plants growing in the Mauna Kea alpine/upper subalpine, we found that adaxial TUV A, measured with a UVA-PAM fluorometer, varied significantly among species but did not differ between native (mean = 6.0%; n = 8 and non-native (mean = 5.8%; n = 11 species. When data were pooled across native and non-native taxa, we also found no significant effect of growth form on TUV A, though woody plants (shrubs and trees were represented solely by native species whereas herbaceous growth forms (grasses and forbs were dominated by non-native species. Along an elevation gradient spanning 2600–3800 m, TUV A was variable (mean range = 6.0–11.2% and strongly correlated with elevation and relative biologically effective UV-B in the exotic V. thapsus; however, TUV A was consistently low (3% and did not vary with elevation in the native

  13. Do non-native plant species affect the shape of productivity-diversity relationships?

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    Drake, J.M.; Cleland, E.E.; Horner-Devine, M. C.; Fleishman, E.; Bowles, C.; Smith, M.D.; Carney, K.; Emery, S.; Gramling, J.; Vandermast, D.B.; Grace, J.B.

    2008-01-01

    The relationship between ecosystem processes and species richness is an active area of research and speculation. Both theoretical and experimental studies have been conducted in numerous ecosystems. One finding of these studies is that the shape of the relationship between productivity and species richness varies considerably among ecosystems and at different spatial scales, though little is known about the relative importance of physical and biological mechanisms causing this variation. Moreover, despite widespread concern about changes in species' global distributions, it remains unclear if and how such large-scale changes may affect this relationship. We present a new conceptual model of how invasive species might modulate relationships between primary production and species richness. We tested this model using long-term data on relationships between aboveground net primary production and species richness in six North American terrestrial ecosystems. We show that primary production and abundance of non-native species are both significant predictors of species richness, though we fail to detect effects of invasion extent on the shapes of the relationship between species richness and primary production.

  14. Ecological impacts of non-native species

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    Wilkinson, John W.

    2012-01-01

    Non-native species are considered one of the greatest threats to freshwater biodiversity worldwide (Drake et al. 1989; Allen and Flecker 1993; Dudgeon et al. 2005). Some of the first hypotheses proposed to explain global patterns of amphibian declines included the effects of non-native species (Barinaga 1990; Blaustein and Wake 1990; Wake and Morowitz 1991). Evidence for the impact of non-native species on amphibians stems (1) from correlative research that relates the distribution or abundance of a species to that of a putative non-native species, and (2) from experimental tests of the effects of a non-native species on survival, growth, development or behaviour of a target species (Kats and Ferrer 2003). Over the past two decades, research on the effects of non-native species on amphibians has mostly focused on introduced aquatic predators, particularly fish. Recent research has shifted to more complex ecological relationships such as influences of sub-lethal stressors (e.g. contaminants) on the effects of non-native species (Linder et al. 2003; Sih et al. 2004), non-native species as vectors of disease (Daszak et al. 2004; Garner et al. 2006), hybridization between non-natives and native congeners (Riley et al. 2003; Storfer et al. 2004), and the alteration of food-webs by non-native species (Nystrom et al. 2001). Other research has examined the interaction of non-native species in terms of facilitation (i.e. one non-native enabling another to become established or spread) or the synergistic effects of multiple non-native species on native amphibians, the so-called invasional meltdown hypothesis (Simerloff and Von Holle 1999). Although there is evidence that some non-native species may interact (Ricciardi 2001), there has yet to be convincing evidence that such interactions have led to an accelerated increase in the number of non-native species and cumulative impacts are still uncertain (Simberloff 2006). Applied research on the control, eradication, and

  15. Impacts of invasive nonnative plant species on the rare forest herb Scutellaria montana

    Science.gov (United States)

    Sikkema, Jordan J.; Boyd, Jennifer N.

    2015-11-01

    Invasive plant species and overabundant herbivore populations have the potential to significantly impact rare plant species given their increased risk for local extirpation and extinction. We used interacting invasive species removal and grazer exclusion treatments replicated across two locations in an occurrence of rare Scutellaria montana (large-flowered skullcap) in Chattanooga, Tennessee, USA, to assess: 1) competition by invasive Ligustrum sinense (Chinese privet) and Lonicera japonica (Japanese honeysuckle) and 2) the role of invasive species in mediating Oedocoilus virginianus (white-tailed deer) grazing of S. montana. Contrary to our hypothesis that invasive species presence would suppress S. montana directly via competition, S. montana individuals experienced a seasonal increase in stem height when invasive species were intact but not when invasive species were removed. Marginally significant results indicated that invasive species may afford S. montana protection from grazers, and we suggest that invasive species also could protect S. montana from smaller herbivores and/or positively influence abiotic conditions. In contrast to growth responses, S. montana individuals protected from O. virginianus exhibited a decrease in flowering between seasons relative to unprotected plants, but invasive species did not affect this variable. Although it has been suggested that invasive plant species may negatively influence S. montana growth and fecundity, our findings do not support related concerns. As such, we suggest that invasive species eradication efforts in S. montana habitat could be more detrimental than positive due to associated disturbance. However, the low level of invasion of our study site may not be representative of potential interference in more heavily infested habitat.

  16. Non-native plant invasions of United States National parks

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    Allen, J.A.; Brown, C.S.; Stohlgren, T.J.

    2009-01-01

    The United States National Park Service was created to protect and make accessible to the public the nation's most precious natural resources and cultural features for present and future generations. However, this heritage is threatened by the invasion of non-native plants, animals, and pathogens. To evaluate the scope of invasions, the USNPS has inventoried non-native plant species in the 216 parks that have significant natural resources, documenting the identity of non-native species. We investigated relationships among non-native plant species richness, the number of threatened and endangered plant species, native species richness, latitude, elevation, park area and park corridors and vectors. Parks with many threatened and endangered plants and high native plant species richness also had high non-native plant species richness. Non-native plant species richness was correlated with number of visitors and kilometers of backcountry trails and rivers. In addition, this work reveals patterns that can be further explored empirically to understand the underlying mechanisms. ?? Springer Science+Business Media B.V. 2008.

  17. Invasional meltdown in northern lakes: Common carp invasion favors non-native plant species

    Science.gov (United States)

    Disturbances can lead to nonrandom changes in community composition due to interactions between the disturbance and the characteristics of species found in the community or available to colonize, producing both winners and losers of disturbance. When the disturbance is a biologic...

  18. Nonnative invasive plants: Maintaining biotic and soceioeconomic integrity along the urban-rural-natural gradient

    Science.gov (United States)

    Cynthia D. Huebner; David J. Nowak; Richard V. Pouyat; Allison R. Bodine

    2012-01-01

    In this chapter, we evaluate nonnative invasive plant species of the urban-rural-natural area gradient in order to reduce negative impacts of invasive plants on native species and ecosystems. This evaluation includes addressing (i) the concept of urban areas as the primary source of invasive plant species and characteristics of urban nonnative plants, including their...

  19. Interactions of fire and nonnative species across an elevation/plant community gradient in Hawaii volcanoes national park

    Science.gov (United States)

    Alison Ainsworth; J. Boone Kauffman

    2010-01-01

    Invasive species interacting with fires pose a relatively unknown, but potentially serious, threat to the tropical forests of Hawaii. Fires may create conditions that facilitate species invasions, but the degree to which this occurs in different tropical plant communities has not been quantified. We documented the survival and establishment of plant species for 2 yr...

  20. Non-native earthworms promote plant invasion by ingesting seeds and modifying soil properties

    OpenAIRE

    Clause, J.; Forey, E.; Lortie, C. J.; Lambert, A. M.; Barot, Sébastien

    2015-01-01

    Earthworms can have strong direct effects on plant communities through consumption and digestion of seeds, however it is unclear how earthworms may influence the relative abundance and composition of plant communities invaded by non-native species. In this study, earthworms, seed banks, and the standing vegetation were sampled in a grassland of central California. Our objectives were i) to examine whether the abundances of non-native, invasive earthworm species and non-native grassland plant ...

  1. Growth strategy, phylogeny and stoichiometry determine the allelopathic potential of native and non-native plants

    NARCIS (Netherlands)

    Grutters, Bart M.C.; Saccomanno, Benedetta; Gross, Elisabeth M.; Van de Waal, Dedmer B.; van Donk, Ellen; Bakker, Elisabeth S.

    2017-01-01

    Secondary compounds can contribute to the success of non-native plant species if they reduce damage by native herbivores or inhibit the growth of native plant competitors. However, there is opposing evidence on whether the secondary com- pounds of non-native plant species are stronger than those of

  2. Plant-soil interactions promote co-occurrence of three nonnative woody shrubs.

    Science.gov (United States)

    Kuebbing, Sara E; Classen, Aimée T; Call, Jaime J; Henning, Jeremiah A; Simberloff, Daniel

    2015-08-01

    Ecosystems containing multiple nonnative plant species are common, but mechanisms promoting their co-occurrence are understudied. Plant-soil interactions contribute to the dominance of singleton species in nonnative ranges because many nonnatives experience stronger positive feedbacks relative to co-occurring natives. Plant-soil interactions could impede other nonnatives if an individual nonnative benefits from its soil community to a greater extent than its neighboring nonnatives, as is seen with natives. However, plant-soil interactions could promote nonnative co-occurrence if a nonnative accumulates beneficial soil mutualists that also assist other nonnatives. Here, we use greenhouse and field experiments to ask whether plant-soil interactions (1) promote the codominance of two common nonnative shrubs (Ligustrum sinense and Lonicera maackii) and (2) facilitate the invasion of a less-common nonnative shrub (Rhamnus davurica) in deciduous forests of the southeastern United States. In the greenhouse, we found that two of the nonnatives, L. maackii and R. davurica, performed better in soils conditioned by nonnative shrubs compared to uninvaded forest soils, which. suggests that positive feedbacks among co-occurring nonnative shrubs can promote continued invasion of a site. In both greenhouse and field experiments, we found consistent signals that the codominance of the nonnatives L. sinense and L. maackii may be at least partially explained by the increased growth of L. sinense in L. maackii soils. Overall, significant effects of plant-soil interactions on shrub performance indicate that plant-soil interactions can potentially structure the co-occurrence patterns of these nonnatives.

  3. Ecological impacts of non-native species: Chapter 2

    Science.gov (United States)

    Pilliod, David S.; Griffiths, R.A.; Kuzmin, S.L.; Heatwole, Harold; Wilkinson, John W.

    2012-01-01

    Non-native species are considered one of the greatest threats to freshwater biodiversity worldwide (Drake et al. 1989; Allen and Flecker 1993; Dudgeon et al. 2005). Some of the first hypotheses proposed to explain global patterns of amphibian declines included the effects of non-native species (Barinaga 1990; Blaustein and Wake 1990; Wake and Morowitz 1991). Evidence for the impact of non-native species on amphibians stems (1) from correlative research that relates the distribution or abundance of a species to that of a putative non-native species, and (2) from experimental tests of the effects of a non-native species on survival, growth, development or behaviour of a target species (Kats and Ferrer 2003). Over the past two decades, research on the effects of non-native species on amphibians has mostly focused on introduced aquatic predators, particularly fish. Recent research has shifted to more complex ecological relationships such as influences of sub-lethal stressors (e.g. contaminants) on the effects of non-native species (Linder et al. 2003; Sih et al. 2004), non-native species as vectors of disease (Daszak et al. 2004; Garner et al. 2006), hybridization between non-natives and native congeners (Riley et al. 2003; Storfer et al. 2004), and the alteration of food-webs by non-native species (Nystrom et al. 2001). Other research has examined the interaction of non-native species in terms of facilitation (i.e. one non-native enabling another to become established or spread) or the synergistic effects of multiple non-native species on native amphibians, the so-called invasional meltdown hypothesis (Simerloff and Von Holle 1999). Although there is evidence that some non-native species may interact (Ricciardi 2001), there has yet to be convincing evidence that such interactions have led to an accelerated increase in the number of non-native species and cumulative impacts are still uncertain (Simberloff 2006). Applied research on the control, eradication, and

  4. Negative, neutral, and positive interactions among nonnative plants: patterns, processes, and management implications.

    Science.gov (United States)

    Kuebbing, Sara E; Nuñez, Martin A

    2015-02-01

    The movement of species is one of the most pervasive forms of global change, and few ecosystems remain uninvaded by nonnative species. Studying species interactions is crucial for understanding their distribution and abundance, particularly for nonnative species because interactions may influence the probability of invasion and consequent ecological impact. Interactions among nonnatives are relatively understudied, though the likelihood of nonnative species co-occurrence is high. We quantify and describe the types of interactions among nonnative plants and determine what factors affect interaction outcomes for ecosystems globally. We reviewed 65 studies comprising 201 observations and recorded the interaction type, traits of the interacting species, and study characteristics. We conducted a census of interaction types and a meta-analysis of experiments that tested nonnative competition intensity. Both methods showed that negative and neutral interactions prevailed, and a number of studies reported that the removal of a dominant nonnative led to competitive release of other nonnatives. Positive interactions were less frequently reported and positive mean effect sizes were rare, but the plant characteristics nitrogen fixation, life cycle (annual or perennial), and functional group significantly influenced positive interactions. Positive interactions were three times more frequent when a neighboring nonnative was a nitrogen fixer and 3.5 times lower when a neighboring nonnative was an annual. Woody plants were two or four times more likely to have positive interactions relative to grasses or herbs, respectively. The prevalence of negative interactions suggests that managers should prepare for reinvasion of sites when treating dominant nonnatives. Though positive interactions were infrequent, managers may be able to anticipate positive interactions among nonnatives based upon traits of the co-occurring invaders. Predicting positive nonnative interactions is an

  5. Neighbour tolerance, not suppression, provides competitive advantage to non-native plants.

    Science.gov (United States)

    Golivets, Marina; Wallin, Kimberly F

    2018-05-01

    High competitive ability has often been invoked as a key determinant of invasion success and ecological impacts of non-native plants. Yet our understanding of the strategies that non-natives use to gain competitive dominance remains limited. Particularly, it remains unknown whether the two non-mutually exclusive competitive strategies, neighbour suppression and neighbour tolerance, are equally important for the competitive advantage of non-native plants. Here, we analyse data from 192 peer-reviewed studies on pairwise plant competition within a Bayesian multilevel meta-analytic framework and show that non-native plants outperform their native counterparts due to high tolerance of competition, as opposed to strong suppressive ability. Competitive tolerance ability of non-native plants was driven by neighbour's origin and was expressed in response to a heterospecific native but not heterospecific non-native neighbour. In contrast to natives, non-native species were not more suppressed by hetero- vs. conspecific neighbours, which was partially due to higher intensity of intraspecific competition among non-natives. Heterogeneity in the data was primarily associated with methodological differences among studies and not with phylogenetic relatedness among species. Altogether, our synthesis demonstrates that non-native plants are competitively distinct from native plants and challenges the common notion that neighbour suppression is the primary strategy for plant invasion success. © 2018 John Wiley & Sons Ltd/CNRS.

  6. Influence of Removal of a Non-native Tree Species Mimosa caesalpiniifolia Benth. on the Regenerating Plant Communities in a Tropical Semideciduous Forest Under Restoration in Brazil

    Science.gov (United States)

    Podadera, Diego S.; Engel, Vera L.; Parrotta, John A.; Machado, Deivid L.; Sato, Luciane M.; Durigan, Giselda

    2015-11-01

    Exotic species are used to trigger facilitation in restoration plantings, but this positive effect may not be permanent and these species may have negative effects later on. Since such species can provide a marketable product (firewood), their harvest may represent an advantageous strategy to achieve both ecological and economic benefits. In this study, we looked at the effect of removal of a non-native tree species ( Mimosa caesalpiniifolia) on the understory of a semideciduous forest undergoing restoration. We assessed two 14-year-old plantation systems (modified "taungya" agroforestry system; and mixed plantation using commercial timber and firewood tree species) established at two sites with contrasting soil properties in São Paulo state, Brazil. The experimental design included randomized blocks with split plots. The natural regeneration of woody species (height ≥0.2 m) was compared between managed (all M. caesalpiniifolia trees removed) and unmanaged plots during the first year after the intervention. The removal of M. caesalpiniifolia increased species diversity but decreased stand basal area. Nevertheless, the basal area loss was recovered after 1 year. The management treatment affected tree species regeneration differently between species groups. The results of this study suggest that removal of M. caesalpiniifolia benefited the understory and possibly accelerated the succession process. Further monitoring studies are needed to evaluate the longer term effects on stand structure and composition. The lack of negative effects of tree removal on the natural regeneration indicates that such interventions can be recommended, especially considering the expectations of economic revenues from tree harvesting in restoration plantings.

  7. Community-level plant-soil feedbacks explain landscape distribution of native and non-native plants.

    Science.gov (United States)

    Kulmatiski, Andrew

    2018-02-01

    Plant-soil feedbacks (PSFs) have gained attention for their potential role in explaining plant growth and invasion. While promising, most PSF research has measured plant monoculture growth on different soils in short-term, greenhouse experiments. Here, five soil types were conditioned by growing one native species, three non-native species, or a mixed plant community in different plots in a common-garden experiment. After 4 years, plants were removed and one native and one non-native plant community were planted into replicate plots of each soil type. After three additional years, the percentage cover of each of the three target species in each community was measured. These data were used to parameterize a plant community growth model. Model predictions were compared to native and non-native abundance on the landscape. Native community cover was lowest on soil conditioned by the dominant non-native, Centaurea diffusa , and non-native community cover was lowest on soil cultivated by the dominant native, Pseudoroegneria spicata . Consistent with plant growth on the landscape, the plant growth model predicted that the positive PSFs observed in the common-garden experiment would result in two distinct communities on the landscape: a native plant community on native soils and a non-native plant community on non-native soils. In contrast, when PSF effects were removed, the model predicted that non-native plants would dominate all soils, which was not consistent with plant growth on the landscape. Results provide an example where PSF effects were large enough to change the rank-order abundance of native and non-native plant communities and to explain plant distributions on the landscape. The positive PSFs that contributed to this effect reflected the ability of the two dominant plant species to suppress each other's growth. Results suggest that plant dominance, at least in this system, reflects the ability of a species to suppress the growth of dominant competitors

  8. Invasive non-native species' provision of refugia for endangered native species.

    Science.gov (United States)

    Chiba, Satoshi

    2010-08-01

    The influence of non-native species on native ecosystems is not predicted easily when interspecific interactions are complex. Species removal can result in unexpected and undesired changes to other ecosystem components. I examined whether invasive non-native species may both harm and provide refugia for endangered native species. The invasive non-native plant Casuarina stricta has damaged the native flora and caused decline of the snail fauna on the Ogasawara Islands, Japan. On Anijima in 2006 and 2009, I examined endemic land snails in the genus Ogasawarana. I compared the density of live specimens and frequency of predation scars (from black rats [Rattus rattus]) on empty shells in native vegetation and Casuarina forests. The density of land snails was greater in native vegetation than in Casuarina forests in 2006. Nevertheless, radical declines in the density of land snails occurred in native vegetation since 2006 in association with increasing predation by black rats. In contrast, abundance of Ogasawarana did not decline in the Casuarina forest, where shells with predation scars from rats were rare. As a result, the density of snails was greater in the Casuarina forest than in native vegetation. Removal of Casuarina was associated with an increased proportion of shells with predation scars from rats and a decrease in the density of Ogasawarana. The thick and dense litter of Casuarina appears to provide refugia for native land snails by protecting them from predation by rats; thus, eradication of rats should precede eradication of Casuarina. Adaptive strategies, particularly those that consider the removal order of non-native species, are crucial to minimizing the unintended effects of eradication on native species. In addition, my results suggested that in some cases a given non-native species can be used to mitigate the impacts of other non-native species on native species.

  9. Native fruit traits may mediate dispersal competition between native and non-native plants

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    Clare Aslan

    2012-02-01

    Full Text Available Seed disperser preferences may mediate the impact of invasive, non-native plant species on their new ecological communities. Significant seed disperser preference for invasives over native species could facilitate the spread of the invasives while impeding native plant dispersal. Such competition for dispersers could negatively impact the fitness of some native plants. Here, we review published literature to identify circumstances under which preference for non-native fruits occurs. The importance of fruit attraction is underscored by several studies demonstrating that invasive, fleshy-fruited plant species are particularly attractive to regional frugivores. A small set of studies directly compare frugivore preference for native vs. invasive species, and we find that different designs and goals within such studies frequently yield contrasting results. When similar native and non-native plant species have been compared, frugivores have tended to show preference for the non-natives. This preference appears to stem from enhanced feeding efficiency or accessibility associated with the non-native fruits. On the other hand, studies examining preference within existing suites of co-occurring species, with no attempt to maximize fruit similarity, show mixed results, with frugivores in most cases acting opportunistically or preferring native species. A simple, exploratory meta-analysis finds significant preference for native species when these studies are examined as a group. We illustrate the contrasting findings typical of these two approaches with results from two small-scale aviary experiments we conducted to determine preference by frugivorous bird species in northern California. In these case studies, native birds preferred the native fruit species as long as it was dissimilar from non-native fruits, while non-native European starlings preferred non-native fruit. However, native birds showed slight, non-significant preference for non-native fruit

  10. Non-native earthworms promote plant invasion by ingesting seeds and modifying soil properties

    Science.gov (United States)

    Clause, Julia; Forey, Estelle; Lortie, Christopher J.; Lambert, Adam M.; Barot, Sébastien

    2015-04-01

    Earthworms can have strong direct effects on plant communities through consumption and digestion of seeds, however it is unclear how earthworms may influence the relative abundance and composition of plant communities invaded by non-native species. In this study, earthworms, seed banks, and the standing vegetation were sampled in a grassland of central California. Our objectives were i) to examine whether the abundances of non-native, invasive earthworm species and non-native grassland plant species are correlated, and ii) to test whether seed ingestion by these worms alters the soil seed bank by evaluating the composition of seeds in casts relative to uningested soil. Sampling locations were selected based on historical land-use practices, including presence or absence of tilling, and revegetation by seed using Phalaris aquatica. Only non-native earthworm species were found, dominated by the invasive European species Aporrectodea trapezoides. Earthworm abundance was significantly higher in the grassland blocks dominated by non-native plant species, and these sites had higher carbon and moisture contents. Earthworm abundance was also positively related to increased emergence of non-native seedlings, but had no effect on that of native seedlings. Plant species richness and total seedling emergence were higher in casts than in uningested soils. This study suggests that there is a potential effect of non-native earthworms in promoting non-native and likely invasive plant species within grasslands, due to seed-plant-earthworm interactions via soil modification or to seed ingestion by earthworms and subsequent cast effects on grassland dynamics. This study supports a growing body of literature for earthworms as ecosystem engineers but highlights the relative importance of considering non-native-native interactions with the associated plant community.

  11. Non-native species in the vascular flora of highlands and mountains of Iceland

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    Pawel Wasowicz

    2016-01-01

    Full Text Available The highlands and mountains of Iceland are one of the largest remaining wilderness areas in Europe. This study aimed to provide comprehensive and up-to-date data on non-native plant species in these areas and to answer the following questions: (1 How many non-native vascular plant species inhabit highland and mountainous environments in Iceland? (2 Do temporal trends in the immigration of alien species to Iceland differ between highland and lowland areas? (3 Does the incidence of alien species in the disturbed and undisturbed areas within Icelandic highlands differ? (4 Does the spread of non-native species in Iceland proceed from lowlands to highlands? and (5 Can we detect hot-spots in the distribution of non-native taxa within the highlands? Overall, 16 non-native vascular plant species were detected, including 11 casuals and 5 naturalized taxa (1 invasive. Results showed that temporal trends in alien species immigration to highland and lowland areas are similar, but it is clear that the process of colonization of highland areas is still in its initial phase. Non-native plants tended to occur close to man-made infrastructure and buildings including huts, shelters, roads etc. Analysis of spatio-temporal patterns showed that the spread within highland areas is a second step in non-native plant colonization in Iceland. Several statically significant hot spots of alien plant occurrences were identified using the Getis-Ord Gi* statistic and these were linked to human disturbance. This research suggests that human-mediated dispersal is the main driving force increasing the risk of invasion in Iceland’s highlands and mountain areas.

  12. Wildland fire in ecosystems: fire and nonnative invasive plants

    Science.gov (United States)

    Kristin Zouhar; Jane Kapler Smith; Steve Sutherland; Matthew L. Brooks

    2008-01-01

    This state-of-knowledge review of information on relationships between wildland fire and nonnative invasive plants can assist fire managers and other land managers concerned with prevention, detection, and eradication or control of nonnative invasive plants. The 16 chapters in this volume synthesize ecological and botanical principles regarding relationships between...

  13. Non-native Species in Floodplain Secondary Forests in Peninsular Malaysia

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    Nor Rasidah Hashim

    2010-01-01

    Full Text Available There is an increasing concern of alien species invading our tropical ecosystems because anthropogenic land use can create conditions in which non-native species thrive. This study is an assessment of bioinvasion using a quantitative survey of non-native plant species in floodplain secondary forests in Peninsular Malaysia. The study area is known to have a long cultivation and settlement history that provides ample time for non-native species introduction. The survey results showed that introduced species constituted 23% of all the identified species, with seven species unique to riparian forest strips and eleven species unique to abandoned paddy fields and the remaining five species being shared between the two secondary forest types. There existed some habitat preferences amongst the species implying both secondary forests were potentially susceptible to bioinvasion. Fourteen species are also invasive elsewhere (PIER invasives whereas fifteen species have acquired local uses such for traditional medicine and food products. The presence of these non-native species could alter native plant succession trajectory, and eventually leads to native species impoverishment if the exotics managed to outcompete the native species. As such, the findings of this study have a far-reaching application for the national biodiversity conservation efforts because it provides the required information on bioinvasion.

  14. Setting Priorities for Monitoring and Managing Non-native Plants: Toward a Practical Approach.

    Science.gov (United States)

    Koch, Christiane; Jeschke, Jonathan M; Overbeck, Gerhard E; Kollmann, Johannes

    2016-09-01

    Land managers face the challenge to set priorities in monitoring and managing non-native plant species, as resources are limited and not all non-natives become invasive. Existing frameworks that have been proposed to rank non-native species require extensive information on their distribution, abundance, and impact. This information is difficult to obtain and often not available for many species and regions. National watch or priority lists are helpful, but it is questionable whether they provide sufficient information for environmental management on a regional scale. We therefore propose a decision tree that ranks species based on more simple albeit robust information, but still provides reliable management recommendations. To test the decision tree, we collected and evaluated distribution data from non-native plants in highland grasslands of Southern Brazil. We compared the results with a national list from the Brazilian Invasive Species Database for the state to discuss advantages and disadvantages of the different approaches on a regional scale. Out of 38 non-native species found, only four were also present on the national list. If management would solely rely on this list, many species that were identified as spreading based on the decision tree would go unnoticed. With the suggested scheme, it is possible to assign species to active management, to monitoring, or further evaluation. While national lists are certainly important, management on a regional scale should employ additional tools that adequately consider the actual risk of non-natives to become invasive.

  15. Non-Native Plant Invasion along Elevation and Canopy Closure Gradients in a Middle Rocky Mountain Ecosystem.

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    Joshua P Averett

    Full Text Available Mountain environments are currently among the ecosystems least invaded by non-native species; however, mountains are increasingly under threat of non-native plant invasion. The slow pace of exotic plant invasions in mountain ecosystems is likely due to a combination of low anthropogenic disturbances, low propagule supply, and extreme/steep environmental gradients. The importance of any one of these factors is debated and likely ecosystem dependent. We evaluated the importance of various correlates of plant invasions in the Wallowa Mountain Range of northeastern Oregon and explored whether non-native species distributions differed from native species along an elevation gradient. Vascular plant communities were sampled in summer 2012 along three mountain roads. Transects (n = 20 were evenly stratified by elevation (~70 m intervals along each road. Vascular plant species abundances and environmental parameters were measured. We used indicator species analysis to identify habitat affinities for non-native species. Plots were ordinated in species space, joint plots and non-parametric multiplicative regression were used to relate species and community variation to environmental variables. Non-native species richness decreased continuously with increasing elevation. In contrast, native species richness displayed a unimodal distribution with maximum richness occurring at mid-elevations. Species composition was strongly related to elevation and canopy openness. Overlays of trait and environmental factors onto non-metric multidimensional ordinations identified the montane-subalpine community transition and over-story canopy closure exceeding 60% as potential barriers to non-native species establishment. Unlike native species, non-native species showed little evidence for high-elevation or closed-canopy specialization. These data suggest that non-native plants currently found in the Wallowa Mountains are dependent on open canopies and disturbance for

  16. Non-Native Plant Invasion along Elevation and Canopy Closure Gradients in a Middle Rocky Mountain Ecosystem.

    Science.gov (United States)

    Averett, Joshua P; McCune, Bruce; Parks, Catherine G; Naylor, Bridgett J; DelCurto, Tim; Mata-González, Ricardo

    2016-01-01

    Mountain environments are currently among the ecosystems least invaded by non-native species; however, mountains are increasingly under threat of non-native plant invasion. The slow pace of exotic plant invasions in mountain ecosystems is likely due to a combination of low anthropogenic disturbances, low propagule supply, and extreme/steep environmental gradients. The importance of any one of these factors is debated and likely ecosystem dependent. We evaluated the importance of various correlates of plant invasions in the Wallowa Mountain Range of northeastern Oregon and explored whether non-native species distributions differed from native species along an elevation gradient. Vascular plant communities were sampled in summer 2012 along three mountain roads. Transects (n = 20) were evenly stratified by elevation (~70 m intervals) along each road. Vascular plant species abundances and environmental parameters were measured. We used indicator species analysis to identify habitat affinities for non-native species. Plots were ordinated in species space, joint plots and non-parametric multiplicative regression were used to relate species and community variation to environmental variables. Non-native species richness decreased continuously with increasing elevation. In contrast, native species richness displayed a unimodal distribution with maximum richness occurring at mid-elevations. Species composition was strongly related to elevation and canopy openness. Overlays of trait and environmental factors onto non-metric multidimensional ordinations identified the montane-subalpine community transition and over-story canopy closure exceeding 60% as potential barriers to non-native species establishment. Unlike native species, non-native species showed little evidence for high-elevation or closed-canopy specialization. These data suggest that non-native plants currently found in the Wallowa Mountains are dependent on open canopies and disturbance for establishment in low

  17. Positive and Negative Impacts of Non-Native Bee Species around the World.

    Science.gov (United States)

    Russo, Laura

    2016-11-28

    Though they are relatively understudied, non-native bees are ubiquitous and have enormous potential economic and environmental impacts. These impacts may be positive or negative, and are often unquantified. In this manuscript, I review literature on the known distribution and environmental and economic impacts of 80 species of introduced bees. The potential negative impacts of non-native bees include competition with native bees for nesting sites or floral resources, pollination of invasive weeds, co-invasion with pathogens and parasites, genetic introgression, damage to buildings, affecting the pollination of native plant species, and changing the structure of native pollination networks. The potential positive impacts of non-native bees include agricultural pollination, availability for scientific research, rescue of native species, and resilience to human-mediated disturbance and climate change. Most non-native bee species are accidentally introduced and nest in stems, twigs, and cavities in wood. In terms of number of species, the best represented families are Megachilidae and Apidae, and the best represented genus is Megachile . The best studied genera are Apis and Bombus , and most of the species in these genera were deliberately introduced for agricultural pollination. Thus, we know little about the majority of non-native bees, accidentally introduced or spreading beyond their native ranges.

  18. Positive and Negative Impacts of Non-Native Bee Species around the World

    Directory of Open Access Journals (Sweden)

    Laura Russo

    2016-11-01

    Full Text Available Though they are relatively understudied, non-native bees are ubiquitous and have enormous potential economic and environmental impacts. These impacts may be positive or negative, and are often unquantified. In this manuscript, I review literature on the known distribution and environmental and economic impacts of 80 species of introduced bees. The potential negative impacts of non-native bees include competition with native bees for nesting sites or floral resources, pollination of invasive weeds, co-invasion with pathogens and parasites, genetic introgression, damage to buildings, affecting the pollination of native plant species, and changing the structure of native pollination networks. The potential positive impacts of non-native bees include agricultural pollination, availability for scientific research, rescue of native species, and resilience to human-mediated disturbance and climate change. Most non-native bee species are accidentally introduced and nest in stems, twigs, and cavities in wood. In terms of number of species, the best represented families are Megachilidae and Apidae, and the best represented genus is Megachile. The best studied genera are Apis and Bombus, and most of the species in these genera were deliberately introduced for agricultural pollination. Thus, we know little about the majority of non-native bees, accidentally introduced or spreading beyond their native ranges.

  19. Effects of Nonnative Ungulate Removal on Plant Communities and Soil Biogeochemistry in Tropical Forests

    Science.gov (United States)

    Cole, R. J.; Litton, C. M.; Giardina, C. P.; Sparks, J. P.

    2014-12-01

    Non-native ungulates have substantial impacts on native ecosystems globally, altering both plant communities and soil biogeochemistry. Across tropical and temperate ecosystems, land managers fence and remove non-native ungulates to conserve native biodiversity, a costly management action, yet long-term outcomes are not well quantified. Specifically, knowledge gaps include: (i) the magnitude and time frame of plant community recovery; (ii) the response of non-native invasive plants; and (iii) changes to soil biogeochemistry. In 2010, we established a series of paired ungulate presence vs. removal plots that span a 20 yr. chronosequence in tropical montane wet forests on the Island of Hawaii to quantify the impacts and temporal legacy of feral pig removal on plant communities and soil biogeochemistry. We also compared soil biogeochemistry in targeted areas of low and high feral pig impact. Our work shows that both native and non-native vegetation respond positively to release from top-down control following removal of feral pigs, but species of high conservation concern recover only if initially present at the time of non-native ungulate removal. Feral pig impacts on soil biogeochemistry appear to last for at least 20 years following ungulate removal. We observed that both soil physical and chemical properties changed with feral pig removal. Soil bulk density and volumetric water content decreased while extractable base cations and inorganic N increased in low vs. high feral pig impact areas. We hypothesize that altered soil biogeochemistry facilitates continued invasions by non-native plants, even decades after non-native ungulate removal. Future work will concentrate on comparisons between wet and dry forest ecosystems and test whether manipulation of soil nutrients can be used to favor native vs. non-native plant establishment.

  20. Seed rain under native and non-native tree species in the Cabo Rojo National Wildlife Refuge, Puerto Rico.

    Science.gov (United States)

    Arias Garcia, Andrea; Chinea, J Danilo

    2014-09-01

    Seed dispersal is a fundamental process in plant ecology and is of critical importance for the restoration of tropical communities. The lands of the Cabo Rojo National Wildlife Refuge (CRNWR), formerly under agriculture, were abandoned in the 1970s and colonized mainly by non-native tree species of degraded pastures. Here we described the seed rain under the most common native and non-native trees in the refuge in an attempt to determine if focal tree geographic origin (native versus non-native) influences seed dispersal. For this, seed rain was sampled for one year under the canopies of four native and four non-native tree species common in this refuge using 40 seed traps. No significant differences were found for the abundance of seeds, or their diversity, dispersing under native versus non-native focal tree species, nor under the different tree species. A significantly different seed species composition was observed reaching native versus non-native focal species. However, this last result could be more easily explained as a function of distance of the closest adults of the two most abundantly dispersed plant species to the seed traps than as a function of the geographic origin of the focal species. We suggest to continue the practice of planting native tree species, not only as a way to restore the community to a condition similar to the original one, but also to reduce the distances needed for effective dispersal.

  1. Eight nonnative plants in western Oregon forests: associations with environment and management.

    Science.gov (United States)

    Andrew. Gray

    2005-01-01

    Nonnative plants have tremendous ecological and economic impacts on plant communities globally, but comprehensive data on the distribution and ecological relationships of individual species is often scarce or nonexistent. The objective of this study was to assess the influence of vegetation type, climate, topography, and management history on the distribution and...

  2. Non-native tree species in urban areas of the city of Nitra

    International Nuclear Information System (INIS)

    Galis, M

    2014-01-01

    Non-native plant species are part of our environment. The introduction of these species is huge conditioned by anthropogenic activities, such as the urban environment is characterized by. During the field surveys of selected town Nitra (Chrenova, Mikova Ves, Zobor), we studied the frequency of non-native tree species in the contact zone. Overall, we found out the presence of 10 alien species, observed in this area. Our results show dominant presence of the species Rhus typhina, followed by the Robinia pseudoacacia and Ailanthus altissima. Individual plants were tied largely to the surrounding of built-up areas, often growns directly in front of houses, or as a part of urban green. (author)

  3. Influence of Removal of a Non-native Tree Species Mimosa caesalpiniifolia Benth. on the Regenerating Plant Communities in a Tropical Semideciduous Forest Under Restoration in Brazil

    Science.gov (United States)

    Diego S. Podadera; Vera L. Engel; John A. Parrotta; Deivid L. Machado; Luciane M. Sato; Giselda Durigan

    2015-01-01

    Exotic species are used to trigger facilitation in restoration plantings, but this positive effect may not be permanent and these species may have negative effects later on. Since such species can provide a marketable product (firewood), their harvest may represent an advantageous strategy to achieve both ecological and economic benefits. In this study, we looked at...

  4. The Role of Fuel Breaks in the Invasion of Nonnative Plants

    Science.gov (United States)

    Merriam, Kyle E.; Keeley, Jon E.; Beyers, Jan L.

    2007-01-01

    Executive Summary Fuel reduction projects have become an increasingly important component of state and federal fuels management programs. However, an unintended result of some pre-fire fuel manipulation projects may be the introduction of nonnative invasive plants. The establishment of nonnative plants within fuel breaks is a serious concern because the presence of invasive species in areas treated to reduce fuels could make adjacent wildland areas more susceptible to invasion, particularly following widespread disturbances such as fires. This report presents the results of a research project investigating the relationship between fuel reduction treatments and the invasion of nonnative plants. Throughout the rest of this document, we will collectively refer to these treatments as fuel breaks, although we sampled a range of fuel breaks described variously as fuel breaks, shaded fuel breaks, defensible fuel reduction zones, defensible fuel profile zones, fuel reduction projects, fuel management zones, wildfire protection zones, and community protection zones.

  5. Determining effective riparian buffer width for nonnative plant exclusion and habitat enhancement

    Science.gov (United States)

    Gavin Ferris; Vincent D' Amico; Christopher K. Williams

    2012-01-01

    Nonnative plants threaten native biodiversity in landscapes where habitats are fragmented. Unfortunately, in developed areas, much of the remaining forested habitat occurs in fragmented riparian corridors. Because forested corridors of sufficient width may allow forest interior specializing native species to retain competitive advantage over edge specialist and...

  6. Are native songbird populations affected by non-native plant invasion?

    Science.gov (United States)

    Amanda M. Conover; Christopher K. Williams; Vincent. D' Amico

    2011-01-01

    Development into forested areas is occurring rapidly across the United States, and many of the remnant forests within suburban landscapes are being fragmented into smaller patches, impacting the quality of this habitat for avian species. An ecological effect linked to forest fragmentation is the invasion of non-native plants into the ecosystem.

  7. Status and management of non-native plant invasion in three of the largest national parks in the United States

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    Scott Abella

    2015-06-01

    Full Text Available Globally, invasion by non-native plants threatens resources that nature reserves are designated to protect. We assessed the status of non-native plant invasion on 1,662, 0.1-ha plots in Death Valley National Park, Mojave National Preserve, and Lake Mead National Recreation Area. These parks comprise 2.5 million ha, 23% of the national park land in the contiguous USA. At least one non-native species inhabited 82% of plots. Thirty-one percent of plots contained one non-native species, 30% two, 17% three, and 4% four to ten non-native species. Red brome (Bromus rubens, an ‘ecosystem engineer’ that alters fire regimes, was most widespread, infesting 60% of plots. By identifying frequency of species through this assessment, early detection and treatment can target infrequent species or minimally invaded sites, while containment strategies could focus on established invaders. We further compared two existing systems for prioritizing species for management and found that a third of species on plots had no rankings available. Moreover, rankings did not always agree between ranking systems for species that were ranked. Presence of multiple non-native species complicates treatment, and while we found that 40% of plots contained both forb and grass invaders, exploiting accelerated phenology of non-natives (compared to native annuals might help manage multi-species invasions. Large sizes of these parks and scale of invasion are formidable challenges for management. Yet, precisely because of their size, these reserves represent opportunities to conserve large landscapes of native species by managing non-native plant invasions.

  8. Phytophagous insects on native and non-native host plants: combining the community approach and the biogeographical approach.

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    Kim Meijer

    Full Text Available During the past centuries, humans have introduced many plant species in areas where they do not naturally occur. Some of these species establish populations and in some cases become invasive, causing economic and ecological damage. Which factors determine the success of non-native plants is still incompletely understood, but the absence of natural enemies in the invaded area (Enemy Release Hypothesis; ERH is one of the most popular explanations. One of the predictions of the ERH, a reduced herbivore load on non-native plants compared with native ones, has been repeatedly tested. However, many studies have either used a community approach (sampling from native and non-native species in the same community or a biogeographical approach (sampling from the same plant species in areas where it is native and where it is non-native. Either method can sometimes lead to inconclusive results. To resolve this, we here add to the small number of studies that combine both approaches. We do so in a single study of insect herbivory on 47 woody plant species (trees, shrubs, and vines in the Netherlands and Japan. We find higher herbivore diversity, higher herbivore load and more herbivory on native plants than on non-native plants, generating support for the enemy release hypothesis.

  9. Occurrence and spread of nonnative invasive plants in stands treated with fire and/or mechanical treatments in the upper piedmont of South Carolina

    Science.gov (United States)

    Ross J. Phillips; Thomas A. Waldrop; Aaron D. Stottlemyer

    2013-01-01

    Increasing numbers of nonnative invasive plant species and the expansion of existing nonnative plant populations provide challenges for land managers trying to achieve commercial and restoration goals. Some methods used to achieve these goals, e.g., prescribed fire and mechanical treatments, may result in disturbances that promote the establishment and spread of...

  10. Native and non-native plants provide similar refuge to invertebrate prey, but less than artificial plants

    NARCIS (Netherlands)

    Grutters, Bart; Pollux, B.J.A.; Verberk, W.C.E.P.; Bakker, E.S.

    2015-01-01

    Non-native species introductions are widespread and can affect ecosystem functioning by altering the structure of food webs. Invading plants often modify habitat structure, which may affect the suitability of vegetation as refuge and could thus impact predator-prey dynamics. Yet little is known

  11. Contrasting xylem vessel constraints on hydraulic conductivity between native and non-native woody understory species

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    Maria S Smith

    2013-11-01

    Full Text Available We examined the hydraulic properties of 82 native and non-native woody species common to forests of Eastern North America, including several congeneric groups, representing a range of anatomical wood types. We observed smaller conduit diameters with greater frequency in non-native species, corresponding to lower calculated potential vulnerability to cavitation index. Non-native species exhibited higher vessel-grouping in metaxylem compared with native species, however, solitary vessels were more prevalent in secondary xylem. Higher frequency of solitary vessels in secondary xylem was related to a lower potential vulnerability index. We found no relationship between anatomical characteristics of xylem, origin of species and hydraulic conductivity, indicating that non-native species did not exhibit advantageous hydraulic efficiency over native species. Our results confer anatomical advantages for non-native species under the potential for cavitation due to freezing, perhaps permitting extended growing seasons.

  12. Ectomycorrhizal fungal communities of native and non-native Pinus and Quercus species in a common garden of 35-year-old trees.

    Science.gov (United States)

    Trocha, Lidia K; Kałucka, Izabela; Stasińska, Małgorzata; Nowak, Witold; Dabert, Mirosława; Leski, Tomasz; Rudawska, Maria; Oleksyn, Jacek

    2012-02-01

    Non-native tree species have been widely planted or have become naturalized in most forested landscapes. It is not clear if native trees species collectively differ in ectomycorrhizal fungal (EMF) diversity and communities from that of non-native tree species. Alternatively, EMF species community similarity may be more determined by host plant phylogeny than by whether the plant is native or non-native. We examined these unknowns by comparing two genera, native and non-native Quercus robur and Quercus rubra and native and non-native Pinus sylvestris and Pinus nigra in a 35-year-old common garden in Poland. Using molecular and morphological approaches, we identified EMF species from ectomycorrhizal root tips and sporocarps collected in the monoculture tree plots. A total of 69 EMF species were found, with 38 species collected only as sporocarps, 18 only as ectomycorrhizas, and 13 both as ectomycorrhizas and sporocarps. The EMF species observed were all native and commonly associated with a Holarctic range in distribution. We found that native Q. robur had ca. 120% higher total EMF species richness than the non-native Q. rubra, while native P. sylvestris had ca. 25% lower total EMF species richness than non-native P. nigra. Thus, across genera, there was no evidence that native species have higher EMF species diversity than exotic species. In addition, we found a higher similarity in EMF communities between the two Pinus species than between the two Quercus species. These results support the naturalization of non-native trees by means of mutualistic associations with cosmopolitan and novel fungi.

  13. Direct and Indirect Influence of Non-Native Neighbours on Pollination and Fruit Production of a Native Plant.

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    Ana Montero-Castaño

    Full Text Available Entomophilous non-native plants can directly affect the pollination and reproductive success of native plant species and also indirectly, by altering the composition and abundance of floral resources in the invaded community. Separating direct from indirect effects is critical for understanding the mechanisms underlying the impacts of non-native species on recipient communities.Our aims are: (a to explore both the direct effect of the non-native Hedysarum coronarium and its indirect effect, mediated by the alteration of floral diversity, on the pollinator visitation rate and fructification of the native Leopoldia comosa and (b to distinguish whether the effects of the non-native species were due to its floral display or to its vegetative interactions.We conducted field observations within a flower removal experimental setup (i.e. non-native species present, absent and with its inflorescences removed at the neighbourhood scale.Our study illustrates the complexity of mechanisms involved in the impacts of non-native species on native species. Overall, Hedysarum increased pollinator visitation rates to Leopoldia target plants as a result of direct and indirect effects acting in the same direction. Due to its floral display, Hedysarum exerted a direct magnet effect attracting visits to native target plants, especially those made by the honeybee. Indirectly, Hedysarum also increased the visitation rate of native target plants. Due to the competition for resources mediated by its vegetative parts, it decreased floral diversity in the neighbourhoods, which was negatively related to the visitation rate to native target plants. Hedysarum overall also increased the fructification of Leopoldia target plants, even though such an increase was the result of other indirect effects compensating for the observed negative indirect effect mediated by the decrease of floral diversity.

  14. Factors influencing non-native tree species distribution in urban landscapes

    Science.gov (United States)

    Wayne C. Zipperer

    2010-01-01

    Non-native species are presumed to be pervasive across the urban landscape. Yet, we actually know very little about their actual distribution. For this study, vegetation plot data from Syracuse, NY and Baltimore, MD were used to examine non-native tree species distribution in urban landscapes. Data were collected from remnant and emergent forest patches on upland sites...

  15. Show me the numbers: What data currently exist for non-native species in the USA?

    Science.gov (United States)

    Crall, Alycia W.; Meyerson, Laura A.; Stohlgren, Thomas J.; Jarnevich, Catherine S.; Newman, Gregory J.; Graham, James

    2006-01-01

    Non-native species continue to be introduced to the United States from other countries via trade and transportation, creating a growing need for early detection and rapid response to new invaders. It is therefore increasingly important to synthesize existing data on non-native species abundance and distributions. However, no comprehensive analysis of existing data has been undertaken for non-native species, and there have been few efforts to improve collaboration. We therefore conducted a survey to determine what datasets currently exist for non-native species in the US from county, state, multi-state region, national, and global scales. We identified 319 datasets and collected metadata for 79% of these. Through this study, we provide a better understanding of extant non-native species datasets and identify data gaps (ie taxonomic, spatial, and temporal) to help guide future survey, research, and predictive modeling efforts.

  16. Evolution under changing climates: climatic niche stasis despite rapid evolution in a non-native plant.

    Science.gov (United States)

    Alexander, Jake M

    2013-09-22

    A topic of great current interest is the capacity of populations to adapt genetically to rapidly changing climates, for example by evolving the timing of life-history events, but this is challenging to address experimentally. I use a plant invasion as a model system to tackle this question by combining molecular markers, a common garden experiment and climatic niche modelling. This approach reveals that non-native Lactuca serriola originates primarily from Europe, a climatic subset of its native range, with low rates of admixture from Asia. It has rapidly refilled its climatic niche in the new range, associated with the evolution of flowering phenology to produce clines along climate gradients that mirror those across the native range. Consequently, some non-native plants have evolved development times and grow under climates more extreme than those found in Europe, but not among populations from the native range as a whole. This suggests that many plant populations can adapt rapidly to changed climatic conditions that are already within the climatic niche space occupied by the species elsewhere in its range, but that evolution to conditions outside of this range is more difficult. These findings can also help to explain the prevalence of niche conservatism among non-native species.

  17. A global organism detection and monitoring system for non-native species

    Science.gov (United States)

    Graham, J.; Newman, G.; Jarnevich, C.; Shory, R.; Stohlgren, T.J.

    2007-01-01

    Harmful invasive non-native species are a significant threat to native species and ecosystems, and the costs associated with non-native species in the United States is estimated at over $120 Billion/year. While some local or regional databases exist for some taxonomic groups, there are no effective geographic databases designed to detect and monitor all species of non-native plants, animals, and pathogens. We developed a web-based solution called the Global Organism Detection and Monitoring (GODM) system to provide real-time data from a broad spectrum of users on the distribution and abundance of non-native species, including attributes of their habitats for predictive spatial modeling of current and potential distributions. The four major subsystems of GODM provide dynamic links between the organism data, web pages, spatial data, and modeling capabilities. The core survey database tables for recording invasive species survey data are organized into three categories: "Where, Who & When, and What." Organisms are identified with Taxonomic Serial Numbers from the Integrated Taxonomic Information System. To allow users to immediately see a map of their data combined with other user's data, a custom geographic information system (GIS) Internet solution was required. The GIS solution provides an unprecedented level of flexibility in database access, allowing users to display maps of invasive species distributions or abundances based on various criteria including taxonomic classification (i.e., phylum or division, order, class, family, genus, species, subspecies, and variety), a specific project, a range of dates, and a range of attributes (percent cover, age, height, sex, weight). This is a significant paradigm shift from "map servers" to true Internet-based GIS solutions. The remainder of the system was created with a mix of commercial products, open source software, and custom software. Custom GIS libraries were created where required for processing large datasets

  18. Germination responses of an invasive species in native and non-native ranges

    Science.gov (United States)

    Jose L. Hierro; Ozkan Eren; Liana Khetsuriani; Alecu Diaconu; Katalin Torok; Daniel Montesinos; Krikor Andonian; David Kikodze; Levan Janoian; Diego Villarreal; Maria Estanga-Mollica; Ragan M. Callaway

    2009-01-01

    Studying germination in the native and non-native range of a species can provide unique insights into processes of range expansion and adaptation; however, traits related to germination have rarely been compared between native and nonnative populations. In a series of common garden experiments, we explored whether differences in the seasonality of precipitation,...

  19. Exploring public perception of non-native species from a visions of nature perspective.

    Science.gov (United States)

    Verbrugge, Laura N H; Van den Born, Riyan J G; Lenders, H J Rob

    2013-12-01

    Not much is known about lay public perceptions of non-native species and their underlying values. Public awareness and engagement, however, are important aspects in invasive species management. In this study, we examined the relations between the lay public's visions of nature, their knowledge about non-native species, and their perceptions of non-native species and invasive species management with a survey administered in the Netherlands. Within this framework, we identified three measures for perception of non-native species: perceived risk, control and engagement. In general, respondents scored moderate values for perceived risk and personal engagement. However, in case of potential ecological or human health risks, control measures were supported. Respondents' images of the human-nature relationship proved to be relevant in engagement in problems caused by invasive species and in recognizing the need for control, while images of nature appeared to be most important in perceiving risks to the environment. We also found that eradication of non-native species was predominantly opposed for species with a high cuddliness factor such as mammals and bird species. We conclude that lay public perceptions of non-native species have to be put in a wider context of visions of nature, and we discuss the implications for public support for invasive species management.

  20. Evolution of an invasive species research program and implications for large-scale management of a non-native, invasive plant pathogen

    Science.gov (United States)

    Christopher A. Lee; Janice M. Alexander; Susan J. Frankel; Yana Valachovic

    2012-01-01

    We conducted a research needs assessment (RNA) in 2010 to gather opinions of "experts" and a larger public on research priorities for Phytophthora ramorum, the pathogen that causes sudden oak death in forest trees and Ramorum blight in ornamental plants. We place these 2010 findings in context with findings of similar P. ramorum...

  1. Recreational freshwater fishing drives non-native aquatic species richness patterns at a continental scale

    Data.gov (United States)

    U.S. Environmental Protection Agency — Aim. Mapping the geographic distribution of non-native aquatic species is a critically important precursor to understanding the anthropogenic and environmental...

  2. An Ecosystem-Service Approach to Evaluate the Role of Non-Native Species in Urbanized Wetlands

    Directory of Open Access Journals (Sweden)

    Rita S. W. Yam

    2015-04-01

    Full Text Available Natural wetlands have been increasingly transformed into urbanized ecosystems commonly colonized by stress-tolerant non-native species. Although non-native species present numerous threats to natural ecosystems, some could provide important benefits to urbanized ecosystems. This study investigated the extent of colonization by non-native fish and bird species of three urbanized wetlands in subtropical Taiwan. Using literature data the role of each non-native species in the urbanized wetland was evaluated by their effect (benefits/damages on ecosystem services (ES based on their ecological traits. Our sites were seriously colonized by non-native fishes (39%–100%, but <3% by non-native birds. Although most non-native species could damage ES regulation (disease control and wastewater purification, some could be beneficial to the urbanized wetland ES. Our results indicated the importance of non-native fishes in supporting ES by serving as food source to fish-eating waterbirds (native, and migratory species due to their high abundance, particularly for Oreochromis spp. However, all non-native birds are regarded as “harmful” species causing important ecosystem disservices, and thus eradication of these bird-invaders from urban wetlands would be needed. This simple framework for role evaluation of non-native species represents a holistic and transferable approach to facilitate decision making on management priority of non-native species in urbanized wetlands.

  3. Assessment of Nonnative Invasive Plants in the DOE Oak Ridge National Environmental Research Park

    Energy Technology Data Exchange (ETDEWEB)

    Drake, S.J.

    2002-11-05

    The Department of Energy (DOE) National Environmental Research Park at Oak Ridge, Tennessee, is composed of second-growth forest stands characteristic of much of the eastern deciduous forest of the Ridge and Valley Province of Tennessee. Human use of natural ecosystems in this region has facilitated the establishment of at least 167 nonnative, invasive plant species on the Research Park. Our objective was to assess the distribution, abundance, impact, and potential for control of the 18 most abundant invasive species on the Research Park. In 2000, field surveys were conducted of 16 management areas on the Research Park (14 Natural Areas, 1 Reference Area, and Walker Branch Watershed) and the Research Park as a whole to acquire qualitative and quantitative data on the distribution and abundance of these taxa. Data from the surveys were used to rank the relative importance of these species using the ''Alien Plant Ranking System, Version 5.1'' developed by the U.S. Geological Survey. Microstegium (Microstegium vimineum) was ranked highest, or most problematic, for the entire Research Park because of its potential impact on natural systems, its tendency to become a management problem, and how difficult it is to control. Microstegium was present in 12 of the 16 individual sites surveyed; when present, it consistently ranked as the most problematic invasive species, particularly in terms of its potential impact on natural systems. Japanese honeysuckle (Lonicera japonica) and Chinese privet (Ligustrum sinense) were the second- and third-most problematic plant species on the Research Park; these two species were present in 12 and 9 of the 16 sites surveyed, respectively, and often ranked second- or third-most problematic. Other nonnative, invasive species, in decreasing rank order, included kudzu (Pueraria montma), multiflora rose (Rosa multiflora), Chinese lespedeza (Lespedeza cuneara), and other species representing a variety of life forms and growth

  4. Nonnative plant response to silvicultural treatments: A model based on disturbance, propagule pressure, and competitive abilities

    Science.gov (United States)

    Steve Sutherland; Cara R. Nelson

    2010-01-01

    Invasion by nonnative plants can result in substantial adverse effects on the functions of native forest ecosystems, including nutrient cycling and fire regimes. Thus, forest managers need to be aware of the potential impacts of management activities, including silvicultural treatments, on nonnative vegetation. To aid in that effort, we created a conceptual model of...

  5. Impacts of non-native Norway spruce plantation on abundance and species richness of ground beetles (Coleoptera: Carabidae

    Directory of Open Access Journals (Sweden)

    Z. Elek

    2001-06-01

    Full Text Available The impacts of non-native Norway spruce plantation on the abundance and species richness of carabids were studied in the Bükk National Park in Hungary, central Europe. Pitfall catches from recently established (5 yr old, young (15 yr after planting, middle-aged (30 yr after planting, old Norway spruce Picea abies plantation (50 yr after planting, and a native submontane beech forest (Fagetum sylvaticae as a control stand were compared.

    Our results showed that deciduous forest species decreased significantly in abundance in the plantations, and appeared in high abundance only in the native beech forest. Furthermore, open habitat species increased remarkably in abundance in the recently established plantation. Carabids were significantly more abundant and species rich in the native forest than in the plantations, while differences were not significant among the plantations. Multiple regression between the abundance and species richness of carabids and twelve environmental measurements showed that pH of the soil, herb cover and density of the carabids’ prey had a significant effect in determining abundance and species richness.

    Our results showed that plantation of non-native Norway spruce species had a detrimental effect on the composition of carabid communities and no regeneration could be observed during the growth of plantations even 50 yr after the establishment. This emphasises the importance of an active nature management practice to facilitate the recolonization of the native species.

  6. Non-native vascular plants from Canary Islands (Spain): nomenclatural and taxonomical adjustments

    OpenAIRE

    Verloove, F.

    2013-01-01

    Se propone correcciones taxonómicas y nomenclaturales respecto a 88 taxones no nativos de la lista de plantas vasculares de las Islas Canarias (España). Non-native vascular plants from Canary Islands (Spain): nomenclatural and taxonomical adjustments. Corrections and other adjustments are proposed for 88 non-native taxa from the checklist of vascular plants from the Canary Islands (Spain).

  7. An Ecosystem-Service Approach to Evaluate the Role of Non-Native Species in Urbanized Wetlands

    Science.gov (United States)

    Yam, Rita S. W.; Huang, Ko-Pu; Hsieh, Hwey-Lian; Lin, Hsing-Juh; Huang, Shou-Chung

    2015-01-01

    Natural wetlands have been increasingly transformed into urbanized ecosystems commonly colonized by stress-tolerant non-native species. Although non-native species present numerous threats to natural ecosystems, some could provide important benefits to urbanized ecosystems. This study investigated the extent of colonization by non-native fish and bird species of three urbanized wetlands in subtropical Taiwan. Using literature data the role of each non-native species in the urbanized wetland was evaluated by their effect (benefits/damages) on ecosystem services (ES) based on their ecological traits. Our sites were seriously colonized by non-native fishes (39%–100%), but wetland ES. Our results indicated the importance of non-native fishes in supporting ES by serving as food source to fish-eating waterbirds (native, and migratory species) due to their high abundance, particularly for Oreochromis spp. However, all non-native birds are regarded as “harmful” species causing important ecosystem disservices, and thus eradication of these bird-invaders from urban wetlands would be needed. This simple framework for role evaluation of non-native species represents a holistic and transferable approach to facilitate decision making on management priority of non-native species in urbanized wetlands. PMID:25860870

  8. Recreational freshwater fishing drives non-native aquatic species richness patterns at a continental scale.

    Science.gov (United States)

    Mapping the geographic distribution of non-native aquatic species is a critically important precursor to understanding the anthropogenic and environmental factors that drive freshwater biological invasions. Such efforts are often limited to local scales and/or to single species, ...

  9. Biological invasions: economic and environmental costs of alien plant, animal, and microbe species

    National Research Council Canada - National Science Library

    Pimentel, David

    2011-01-01

    ...: Economic and Environmental Costs of Alien Plant, Animal, and Microbe Species, this reference discusses how non-native species invade new ecosystems and the subsequent economic and environmental effects of these species...

  10. Growth form and distribution of introduced plants in their native and non-native ranges in Eastern Asia and North America

    Science.gov (United States)

    Robert E. Ricklefs; Qinfeng Guo; Hong Qian

    2008-01-01

    There is a growing interest in understanding the influence of plant traits on their ability to spread in non-native regions. Many studies addressing this issue have been based on relatively small areas or restricted taxonomic groups. Here, we analyse a large data base involving 1567 plant species introduced between Eastern Asia and North America or from elsewhere to...

  11. Invasions by two non-native insects alter regional forest species composition and successional trajectories

    Science.gov (United States)

    Randall S. Morin; Andrew M. Liebhold

    2015-01-01

    While invasions of individual non-native phytophagous insect species are known to affect growth and mortality of host trees, little is known about how multiple invasions combine to alter forest dynamics over large regions. In this study we integrate geographical data describing historical invasion spread of the hemlock woolly adelgid, Adelges tsugae...

  12. Impacts of nonnative invasive species on US forests and recommendations for policy and management

    Science.gov (United States)

    W. Keith Moser; Edward L. Barnard; Ronald F. Billings; Susan J. Crocker; Andrew N. Gray; George G. Ice; Mee-Sook Kim; Richard Reid; Sue U. Rodman; William H. McWilliams

    2009-01-01

    The introduction of nonnative invasive species (NNIS) into the United States has had tremendous impacts on the nation's commercial and urban forest resources. Of principal concern are the effects of NNIS on forest composition, structure, function, productivity, and patterns of carbon sequestration. In 2006, the Society of American Foresters commissioned an ad hoc...

  13. Vulnerability of freshwater native biodiversity to non-native species invasions across the continental United States

    Science.gov (United States)

    Background/Question/Methods Non-native species pose one of the greatest threats to native biodiversity. The literature provides plentiful empirical and anecdotal evidence of this phenomenon; however, such evidence is limited to local or regional scales. Employing geospatial analy...

  14. Non-native species impacts on pond occupancy by an anuran

    Science.gov (United States)

    Adams, Michael J.; Pearl, Christopher A.; Galvan, Stephanie; McCreary, Brome

    2011-01-01

    Non-native fish and bullfrogs (Lithobates catesbeianus; Rana catesbeiana) are frequently cited as factors contributing to the decline of ranid frogs in the western United States (Bradford 2005). This hypothesis is supported by studies showing competition with or predation by these introduced species (Kupferberg 1997, Kiesecker and Blaustein 1998, Lawler et al. 1999, Knapp et al. 2001) and studies suggesting a deficit of native frogs at sites occupied by bullfrogs or game fish (Hammerson 1982, Schwalbe and Rosen 1988, Fisher and Shaffer 1996, Adams 1999). Conversely, other studies failed to find a negative association between native ranids and bullfrogs and point out that presence of non-native species correlates with habitat alterations that could also contribute to declines of native species (Hayes and Jennings 1986; Adams 1999, 2000; Pearl et al. 2005). A criticism of these studies is that they may not detect an effect of non-native species if the process of displacement is at an early stage. We are not aware of any studies that have monitored a set of native frog populations to determine if non-native species predict population losses. Our objective was to study site occupancy trends in relation to non-native species for northern red-legged frogs (Rana aurora) on federal lands in the southern Willamette Valley, Oregon. We conducted a 5-yr monitoring study to answer the following questions about the status and trends of the northern red-legged frog: 1) What is the rate of local extinction (how often is a site that is occupied in year t unoccupied in year t+1) and what factors predict variation in local extinction? and 2) What is the rate of colonization (how often is a site that is unoccupied in year t occupied in year t+1) and what factors predict variation in colonization? The factors we hypothesized for local extinction were: 1) bullfrog presence, 2) bullfrogs mediated by wetland vegetation, 3) non-native fish (Centrarchidae), 4) non-native fish mediated by

  15. Differences in Competitive Ability between Plants from Nonnative and Native Populations of a Tropical Invader Relates to Adaptive Responses in Abiotic and Biotic Environments

    Science.gov (United States)

    Liao, Zhi-Yong; Zhang, Ru; Barclay, Gregor F.; Feng, Yu-Long

    2013-01-01

    The evolution of competitive ability of invasive plant species is generally studied in the context of adaptive responses to novel biotic environments (enemy release) in introduced ranges. However, invasive plants may also respond to novel abiotic environments. Here we studied differences in competitive ability between Chromolaena odorata plants of populations from nonnative versus native ranges, considering biogeographical differences in both biotic and abiotic environments. An intraspecific competition experiment was conducted at two nutrient levels in a common garden. In both low and high nutrient treatments, C. odorata plants from nonnative ranges showed consistently lower root to shoot ratios than did plants from native ranges grown in both monoculture and competition. In the low nutrient treatment, C. odorata plants from nonnative ranges showed significantly lower competitive ability (competition-driven decreases in plant height and biomass were more), which was associated with their lower root to shoot ratios and higher total leaf phenolic content (defense trait). In the high nutrient treatment, C. odorata plants from nonnative ranges showed lower leaf toughness and cellulosic contents (defense traits) but similar competitive ability compared with plants from native ranges, which was also associated with their lower root to shoot ratios. Our results indicate that genetically based shifts in biomass allocation (responses to abiotic environments) also influence competitive abilities of invasive plants, and provide a first potential mechanism for the interaction between range and environment (environment-dependent difference between ranges). PMID:23977140

  16. Prevention, early detection and containment of invasive, nonnative plants in the Hawaiian Islands: current efforts and needs

    Science.gov (United States)

    Christoph Kueffer,; Loope, Lloyd

    2009-01-01

    Introduction: Invasive, non-native plants (or environmental weeds) have long been recognized as a major threat to the native biodiversity of oceanic islands (Cronk & Fuller, 1995; Denslow, 2003). Globally, several hundred non-native plant species have been reported to have major impacts on natural areas on oceanic islands (Kueffer et al., 2009). In Hawaii, at least some 50 non-native plant species reach dominance in natural areas (Kueffer et al., 2009) and many of them are known to impact ecosystem processes or biodiversity. One example is the invasive Australian tree fern (Cyathea cooperi), which has been shown to be very efficient at utilizing soil nitrogen and can grow six times as rapidly in height, maintain four times more fronds, and produce significantly more fertile fronds per month than the native Hawaiian endemic tree ferns, Cibotium spp. (Durand & Goldstein, 2001a, b). Additionally, while native tree ferns provide an ideal substrate for epiphytic growth of many understory ferns and flowering plants, the Australian tree fern has the effect of impoverishing the understory and failing to support an abundance of native epiphytes (Medeiros & Loope, 1993). Other notorious examples of invasive plant species problematic for biodiversity and ecosystem processes in Hawaii include miconia (Miconia calvescens), strawberry guava (Psidium cattleianum), albizia (Falcataria moluccana), firetree (Morella faya), clidemia (Clidemia hirta), kahili ginger (Hedychium gardnerianum), and fountain grass (Pennisetum setaceum), to name just a few. Fireweed (Senecio madagascariensis) is a recent example of a seriously problematic invasive species for Hawaii’s agriculture and is damaging certain high-elevations native ecosystems as well.

  17. Functional diversity measures revealed impacts of non-native species and habitat degradation on species-poor freshwater fish assemblages.

    Science.gov (United States)

    Colin, Nicole; Villéger, Sébastien; Wilkes, Martin; de Sostoa, Adolfo; Maceda-Veiga, Alberto

    2018-06-01

    Trait-based ecology has been developed for decades to infer ecosystem responses to stressors based on the functional structure of communities, yet its value in species-poor systems is largely unknown. Here, we used an extensive dataset in a Spanish region highly prone to non-native fish invasions (15 catchments, N=389 sites) to assess for the first time how species-poor communities respond to large-scale environmental gradients using a taxonomic and functional trait-based approach in riverine fish. We examined total species richness and three functional trait-based indices available when many sites have ≤3 species (specialization, FSpe; originality, FOri and entropy, FEnt). We assessed the responses of these taxonomic and functional indices along gradients of altitude, water pollution, physical habitat degradation and non-native fish biomass. Whilst species richness was relatively sensitive to spatial effects, functional diversity indices were responsive across natural and anthropogenic gradients. All four diversity measures declined with altitude but this decline was modulated by physical habitat degradation (richness, FSpe and FEnt) and the non-native:total fish biomass ratio (FSpe and FOri) in ways that varied between indices. Furthermore, FSpe and FOri were significantly correlated with Total Nitrogen. Non-native fish were a major component of the taxonomic and functional structure of fish communities, raising concerns about potential misdiagnosis between invaded and environmentally-degraded river reaches. Such misdiagnosis was evident in a regional fish index widely used in official monitoring programs. We recommend the application of FSpe and FOri to extensive datasets from monitoring programs in order to generate valuable cross-system information about the impacts of non-native species and habitat degradation, even in species-poor systems. Scoring non-native species apart from habitat degradation in the indices used to determine ecosystem health is

  18. Understanding the threats posed by non-native species: public vs. conservation managers.

    Directory of Open Access Journals (Sweden)

    Rodolphe E Gozlan

    Full Text Available Public perception is a key factor influencing current conservation policy. Therefore, it is important to determine the influence of the public, end-users and scientists on the prioritisation of conservation issues and the direct implications for policy makers. Here, we assessed public attitudes and the perception of conservation managers to five non-native species in the UK, with these supplemented by those of an ecosystem user, freshwater anglers. We found that threat perception was not influenced by the volume of scientific research or by the actual threats posed by the specific non-native species. Media interest also reflected public perception and vice versa. Anglers were most concerned with perceived threats to their recreational activities but their concerns did not correspond to the greatest demonstrated ecological threat. The perception of conservation managers was an amalgamation of public and angler opinions but was mismatched to quantified ecological risks of the species. As this suggests that invasive species management in the UK is vulnerable to a knowledge gap, researchers must consider the intrinsic characteristics of their study species to determine whether raising public perception will be effective. The case study of the topmouth gudgeon Pseudorasbora parva reveals that media pressure and political debate has greater capacity to ignite policy changes and impact studies on non-native species than scientific evidence alone.

  19. Vision of a cyberinfrastructure for nonnative, invasive species management

    Science.gov (United States)

    2008-01-01

    Although the quantity of data on the location, status, and management of invasive species is ever increasing, invasive species data sets are often difficult to obtain and integrate. A cyberinfrastructure for such information could make these data available for Internet users. The data can be used to create regional watch lists, to send e-mail alerts when a new species enters a region, to construct models of species' current and future distributions, and to inform management. Although the exchange of environmental data over the Internet in the form of raster data is maturing, and the exchange of species occurrence data is developing quickly, there is room for improvement. In this article, we present a vision for a comprehensive invasive species cyberinfrastructure that is capable of accessing data effectively, creating models of invasive species spread, and distributing this information.

  20. Evaluating ecosystem services provided by non-native species: an experimental test in California grasslands.

    Science.gov (United States)

    Stein, Claudia; Hallett, Lauren M; Harpole, W Stanley; Suding, Katharine N

    2014-01-01

    The concept of ecosystem services--the benefits that nature provides to human's society--has gained increasing attention over the past decade. Increasing global abiotic and biotic change, including species invasions, is threatening the secure delivery of these ecosystem services. Efficient evaluation methods of ecosystem services are urgently needed to improve our ability to determine management strategies and restoration goals in face of these new emerging ecosystems. Considering a range of multiple ecosystem functions may be a useful way to determine such strategies. We tested this framework experimentally in California grasslands, where large shifts in species composition have occurred since the late 1700's. We compared a suite of ecosystem functions within one historic native and two non-native species assemblages under different grazing intensities to address how different species assemblages vary in provisioning, regulatory and supporting ecosystem services. Forage production was reduced in one non-native assemblage (medusahead). Cultural ecosystem services, such as native species diversity, were inherently lower in both non-native assemblages, whereas most other services were maintained across grazing intensities. All systems provided similar ecosystem services under the highest grazing intensity treatment, which simulated unsustainable grazing intensity. We suggest that applying a more comprehensive ecosystem framework that considers multiple ecosystem services to evaluate new emerging ecosystems is a valuable tool to determine management goals and how to intervene in a changing ecosystem.

  1. Environmental niche separation between native and non-native benthic invertebrate species: Case study of the northern Baltic Sea.

    Science.gov (United States)

    Jänes, Holger; Herkül, Kristjan; Kotta, Jonne

    2017-10-01

    Knowledge and understanding of geographic distributions of species is crucial for many aspects in ecology, conservation, policy making and management. In order to reach such an understanding, it is important to know abiotic variables that impact and drive distributions of native and non-native species. We used an existing long-term macrobenthos database for species presence-absence information and biomass estimates at different environmental gradients in the northern Baltic Sea. Region specific abiotic variables (e.g. salinity, depth) were derived from previously constructed bathymetric and hydrodynamic models. Multidimensional ordination techniques were then applied to investigate potential niche space separation between all native and non-native invertebrates in the northern Baltic Sea. Such an approach allowed to obtain data rich and robust estimates of the current native and non-native species distributions and outline important abiotic parameters influencing the observed pattern. The results showed clear niche space separation between native and non-native species. Non-native species were situated in an environmental space characterized by reduced salinity, high temperatures, high proportion of soft seabed and decreased depth and wave exposure whereas native species displayed an opposite pattern. Different placement of native and non-native species along the studied environmental niche space is likely to be explained by the differences in their evolutionary history, human mediated activities and geological youth of the Baltic Sea. The results of this study can provide early warnings and effectively outline coastal areas in the northern Baltic Sea that are prone to further range expansion of non-native species as climate change is expected to significantly reduce salinity and increase temperature in wide coastal areas, both supporting the disappearance of native and appearance of non-native species. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Regional patterns of major nonnative invasive plants and associated factors in upper Midwest forests

    Science.gov (United States)

    Zhaofei Fan; W. Keith Moser; Mark H. Hansen; Mark D. Nelson

    2013-01-01

    Nonnative invasive plants (IPs) are rapidly spreading into natural ecosystems (e.g., forests and grasslands). Potential threats of IP invasion into natural ecosystems include biodiversity loss, structural and environmental change, habitat degradation, and economic losses. The Upper Midwest of the United States encompasses the states of Illinois, Indiana, Iowa, Michigan...

  3. The influence of ungulates on non-native plant invasions in forests and rangelands: a review.

    Science.gov (United States)

    Catherine G. Parks; Michael J. Wisdom; John G. Kie

    2005-01-01

    Herbivory by wild and domestic ungulates can strongly influence vegetation composition and productivity in forest and range ecosystems. However, the role of ungulates as contributors to the establishment and spread of non-native invasive plants is not well known. Ungulates spread seeds through endozoochory (passing through an animal's digestive tract) or...

  4. Introduction of non-native marine fish species to the Canary Islands waters through oil platforms as vectors

    Science.gov (United States)

    Pajuelo, José G.; González, José A.; Triay-Portella, Raül; Martín, José A.; Ruiz-Díaz, Raquel; Lorenzo, José M.; Luque, Ángel

    2016-11-01

    This work documents the introduction of non-native fish species to the Canary Islands (central-eastern Atlantic) through oil rigs. Methodological approaches have included surveys by underwater visual censuses around and under oil platforms and along the docking area of rigs at the Port of Las Palmas. Eleven non-native fish species were registered. Paranthias furcifer, Abudefduf hoefleri, Acanthurus bahianus, Acanthurus chirurgus, and Acanthurus coeruleus are first recorded from the Canaries herein. Other three species could not be identified, although they have never been observed in the Canaries. Cephalopholis taeniops, Abudefduf saxatilis, and Acanthurus monroviae had been previously recorded. Native areas of these species coincide with the areas of origin and the scale of oil rigs with destination the Port of Las Palmas. The absence of native species in the censuses at rigs and their presence at rigs docking area, together with the observation of non-native species after the departure of platforms, reject the possibility that these non-native species were already present in the area introduced by another vector. C. taeniops, A. hoefleri, A. saxatilis, A. chirurgus, A. coeruleus and A. monroviae are clearly seafarer species. A. bahianus seems to be a potential seafarer species. P. furcifer is a castaway species. For the moment, the number of individuals of the non-native species in marine ecosystems of the Canaries seems to be low, and more investigation is needed for controlling these translocations.

  5. Herbicides: an unexpected ally for native plants in the war against invasive species

    Science.gov (United States)

    Andrea Watts; Tim Harrington; Dave Peter

    2015-01-01

    Herbicides are primarily used for protecting agricultural crops from weeds and controlling vegetation competition in newly planted forest stands. Yet for over 40 years, they have also proven useful in controlling invasive plant species in natural areas. Nonnative invasive plant species, if not controlled, can displace native species and disrupt an ecosystem by changing...

  6. Competitive effects of non-native plants are lowest in native plant communities that are most vulnerable to invasion

    Science.gov (United States)

    J.Stephen Brewer; W. Chase Bailey

    2014-01-01

    Despite widespread acknowledgment that disturbance favors invasion, a hypothesis that has received little attention is whether non-native invaders have greater competitive effects on native plants in undisturbed habitats than in disturbed habitats. This hypothesis derives from the assumption that competitive interactions are more persistent in habitats that have not...

  7. Is 30 years enough time to niche segregation between a non-native and a native congeneric fish species? Evidences from stable isotopes

    Directory of Open Access Journals (Sweden)

    Gustavo Henrique Zaia Alves

    2015-12-01

    Full Text Available The invasion of non-native species that are phylogenetically similar to native species was observed in the Upper Paraná River following the construction of the Itaipu hydroelectric plant and subsequent removal of a natural geographic barrier (Sete Quedas Falls. Endemic fish species from the Lower Paraná River, such as the piranha Serrasalmus marginatus, successfully colonized the new environment. A few years later, S. marginatus had become the dominant species, while the prevalence of the congeneric species, Serrasalmus maculatus, had declined. Considering that the two piranha species naturally coexist in the Pantanal and that S. marginatus is a non-native species in the Upper Paraná River floodplain, we hypothesized that trophic niche overlap between Serrasalmus species only occurred in the Upper Paraná River floodplain due to short-term co-existence. The study area in which the isotopic niche overlap between S. maculatus and S. marginatus was evaluated consisted of two ponds located in different floodplains, the Pantanal and the Upper Paraná River. We used carbon and nitrogen stable isotope analysis to elucidate the differences in the energy intake by the native and non-native species. We used mixing models and calculated the isotopic niche area and niche overlap to infer the nature of the trophic interactions between the species in both habitats. According to the mixing model, the predominant source of carbon for both species was terrestrial. Nevertheless, in Upper Paraná River, the δ13C signature of the two species differed significantly and the non-native species had a greater niche width than the native species. In the Pantanal, there were no differences in δ13C, but the species differed with respect to δ 15N, and the niche widths were narrow for both species.Based on these results, it can be inferred that the species depend on different food sources. Piranhas obtain energy from distinct prey species, which probably consume

  8. NIS occurrence - Non-native species impacts on threatened and endangered salmonids

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The objectives of this project: a) Identify the distribution of non-natives in the Columbia River Basin b) Highlight the impacts of non-natives on salmonids c)...

  9. Riparian Vegetation Response to the March 2008 Short-Duration, High-Flow Experiment-Implications of Timing and Frequency of Flood Disturbance on Nonnative Plant Establishment Along the Colorado River Below Glen Canyon Dam

    Science.gov (United States)

    Ralston, Barbara E.

    2010-01-01

    Riparian plant communities exhibit various levels of diversity and richness. These communities are affected by flooding and are vulnerable to colonization by nonnative species. Since 1996, a series of three high-flow experiments (HFE), or water releases designed to mimic natural seasonal flooding, have been conducted at Glen Canyon Dam, Ariz., primarily to determine the effectiveness of using high flows to conserve sediment, a limited resource. These experiments also provide opportunities to examine the susceptibility of riparian plant communities to nonnative species invasions. The third and most recent HFE was conducted from March 5 to 9, 2008, and scientists with the U.S. Geological Survey's Grand Canyon Monitoring and Research Center examined the effects of high flows on riparian vegetation as part of the overall experiment. Total plant species richness, nonnative species richness, percent plant cover, percent organic matter, and total carbon measured from sediment samples were compared for Grand Canyon riparian vegetation zones immediately following the HFE and 6 months later. These comparisons were used to determine if susceptibility to nonnative species establishment varied among riparian vegetation zones and if the timing of the HFE affected nonnative plant establishment success. The 2008 HFE primarily buried vegetation rather than scouring it. Percent nonnative cover did not differ among riparian vegetation zones; however, in the river corridor affected by Glen Canyon Dam operations, nonnative species richness showed significant variation. For example, species richness was significantly greater immediately after and 6 months following the HFE in the hydrologic zone farthest away from the shoreline, the area that represents the oldest riparian zone within the post-dam riparian area. In areas closer to the river channel, tamarisk (Tamarix ramosissima X chinensis) seedling establishment occurred (tamarisk seed production, or in 1986, a year following several

  10. Species replacement by a nonnative salmonid alters ecosystem function by reducing prey subsidies that support riparian spiders

    Science.gov (United States)

    Benjamin, J.R.; Fausch, K.D.; Baxter, C.V.

    2011-01-01

    Replacement of a native species by a nonnative can have strong effects on ecosystem function, such as altering nutrient cycling or disturbance frequency. Replacements may cause shifts in ecosystem function because nonnatives establish at different biomass, or because they differ from native species in traits like foraging behavior. However, no studies have compared effects of wholesale replacement of a native by a nonnative species on subsidies that support consumers in adjacent habitats, nor quantified the magnitude of these effects. We examined whether streams invaded by nonnative brook trout (Salvelinus fontinalis) in two regions of the Rocky Mountains, USA, produced fewer emerging adult aquatic insects compared to paired streams with native cutthroat trout (Oncorhynchus clarkii), and whether riparian spiders that depend on these prey were less abundant along streams with lower total insect emergence. As predicted, emergence density was 36% lower from streams with the nonnative fish. Biomass of brook trout was higher than the cutthroat trout they replaced, but even after accounting for this difference, emergence was 24% lower from brook trout streams. More riparian spiders were counted along streams with greater total emergence across the water surface. Based on these results, we predicted that brook trout replacement would result in 6-20% fewer spiders in the two regions. When brook trout replace cutthroat trout, they reduce cross-habitat resource subsidies and alter ecosystem function in stream-riparian food webs, not only owing to increased biomass but also because traits apparently differ from native cutthroat trout. ?? 2011 Springer-Verlag.

  11. Hierarchical faunal filters: An approach to assessing effects of habitat and nonnative species on native fishes

    Science.gov (United States)

    Quist, M.C.; Rahel, F.J.; Hubert, W.A.

    2005-01-01

    Understanding factors related to the occurrence of species across multiple spatial and temporal scales is critical to the conservation and management of native fishes, especially for those species at the edge of their natural distribution. We used the concept of hierarchical faunal filters to provide a framework for investigating the influence of habitat characteristics and normative piscivores on the occurrence of 10 native fishes in streams of the North Platte River watershed in Wyoming. Three faunal filters were developed for each species: (i) large-scale biogeographic, (ii) local abiotic, and (iii) biotic. The large-scale biogeographic filter, composed of elevation and stream-size thresholds, was used to determine the boundaries within which each species might be expected to occur. Then, a local abiotic filter (i.e., habitat associations), developed using binary logistic-regression analysis, estimated the probability of occurrence of each species from features such as maximum depth, substrate composition, submergent aquatic vegetation, woody debris, and channel morphology (e.g., amount of pool habitat). Lastly, a biotic faunal filter was developed using binary logistic regression to estimate the probability of occurrence of each species relative to the abundance of nonnative piscivores in a reach. Conceptualising fish assemblages within a framework of hierarchical faunal filters is simple and logical, helps direct conservation and management activities, and provides important information on the ecology of fishes in the western Great Plains of North America. ?? Blackwell Munksgaard, 2004.

  12. Susceptibility of burned black spruce (Picea mariana) forests to non-native plant invasions in interior Alaska

    Science.gov (United States)

    Katie V. Spellman; Christa P.H. Mulder; Teresa N. Hollingsworth

    2014-01-01

    As climate rapidly warms at high-latitudes, the boreal forest faces the simultaneous threats of increasing invasive plant abundances and increasing area burned by wildfire. Highly flammable and widespread black spruce (Picea mariana) forest represents a boreal habitat that may be increasingly susceptible to non-native plant invasion. This study assess the role of burn...

  13. SEASONALITY OF ANNUAL PLANT ESTABLISHMENT INFLUENCES THE INTERACTIONBETWEEN THE NON-NATIVE ANNUAL GRASS BROMUS MADRITENSIS SSP. RUBENS AND MOJAVE DESERT PERENNIALS

    Energy Technology Data Exchange (ETDEWEB)

    L A. DEFALCO; G. C. FERNANDEZ; R. S. NOWAK

    2004-01-01

    Competition between native and non-native species can change the composition and structure of plant communities, but in deserts the timing of non-native plant establishment can modulate their impacts to native species. In a field experiment, we varied densities of the non-native annual grass Bromus madritensis ssp. rubens around individuals of three native perennials--Larrea iridentata, Achnatherum hymenoides, and Pleuraphis rigida--in either winter or spring. Additional plots were prepared for the Same perennial species and seasons, but with a mixture of native annual species. Relative growth rates of perennial shoots (RGRs) declined with increasing Bromus biomass when Bromus that was established in winter had 2-3 mo of growth and high water use before perennial growth began. However, this high water use did not significantly reduce water potentials for the perennials, suggesting Bromus that established earlier depleted other soil resources, such as N, otherwise used by perennial plants. Spring-established Bromus had low biomass even at higher densities and did not effectively reduce RGRs, resulting in an overall lower impact to perennials than when Bromus was established in winter. Similarly, growth and reproduction of perennials with mixed annuals as neighbors did not differ from those with Bromus neighbors of equivalent biomass, but densities of these annuals did not support the high biomass necessary to reduce perennial growth. Thus, impacts of native Mojave Desert annuals to perennials are expected to be lower than those of Bromus because seed dormancy and narrow requirements for seedling survivorship produce densities and biomass lower than those achieved by Bromus. In comparing the effects of Bromus among perennial species, the impact of increased Bromus biomass on RGR was lower for Larrea than for the two perennial grasses, probably because Lurrea maintains low growth rates throughout the year, even after Bromus has completed its life cycle. This contrasts

  14. Above- and below-ground effects of plant diversity depend on species origin

    DEFF Research Database (Denmark)

    Kuebbing, Sara E.; Classen, Aimee Taylor; Sanders, Nate

    2015-01-01

    -interaction models to describe how species' interactions influenced diversity-productivity relationships. Communities with more species had higher total biomass than did monoculture communities, but native and nonnative communities diverged in root : shoot ratios and the mechanism responsible for increased......Although many plant communities are invaded by multiple nonnative species, we have limited information on how a species' origin affects ecosystem function. We tested how differences in species richness and origin affect productivity and seedling establishment. We created phylogenetically paired...... native and nonnative plant communities in a glasshouse experiment to test diversity-productivity relationships and responsible mechanisms (i.e. selection or complementarity effects). Additionally, we tested how productivity and associated mechanisms influenced seedling establishment. We used diversity...

  15. Can a native rodent species limit the invasive potential of a non-native rodent species in tropical agroforest habitats?

    Science.gov (United States)

    Stuart, Alexander M; Prescott, Colin V; Singleton, Grant R

    2016-06-01

    Little is known about native and non-native rodent species interactions in complex tropical agroecosystems. We hypothesised that the native non-pest rodent Rattus everetti may be competitively dominant over the invasive pest rodent Rattus tanezumi within agroforests. We tested this experimentally by using pulse removal for three consecutive months to reduce populations of R. everetti in agroforest habitat, and assessed over 6 months the response of R. tanezumi and other rodent species. Following removal, R. everetti individuals rapidly immigrated into removal sites. At the end of the study period, R. tanezumi were larger and there was a significant shift in their microhabitat use with respect to the use of ground vegetation cover following the perturbation of R. everetti. Irrespective of treatment, R. tanezumi selected microhabitat with less tree canopy cover, indicative of severely disturbed habitat, whereas R. everetti selected microhabitat with a dense canopy. Our results suggest that sustained habitat disturbance in agroforests favours R. tanezumi, while the regeneration of agroforests towards a more natural state would favour native species and may reduce pest pressure in adjacent crops. In addition, the rapid recolonisation of R. everetti suggests this species would be able to recover from non-target impacts of short-term rodent pest control. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  16. A nonnative and a native fungal plant pathogen similarly stimulate ectomycorrhizal development but are perceived differently by a fungal symbiont.

    Science.gov (United States)

    Zampieri, Elisa; Giordano, Luana; Lione, Guglielmo; Vizzini, Alfredo; Sillo, Fabiano; Balestrini, Raffaella; Gonthier, Paolo

    2017-03-01

    The effects of plant symbionts on host defence responses against pathogens have been extensively documented, but little is known about the impact of pathogens on the symbiosis and if such an impact may differ for nonnative and native pathogens. Here, this issue was addressed in a study of the model system comprising Pinus pinea, its ectomycorrhizal symbiont Tuber borchii, and the nonnative and native pathogens Heterobasidion irregulare and Heterobasidion annosum, respectively. In a 6-month inoculation experiment and using both in planta and gene expression analyses, we tested the hypothesis that H. irregulare has greater effects on the symbiosis than H. annosum. Although the two pathogens induced the same morphological reaction in the plant-symbiont complex, with mycorrhizal density increasing exponentially with pathogen colonization of the host, the number of target genes regulated in T. borchii in plants inoculated with the native pathogen (i.e. 67% of tested genes) was more than twice that in plants inoculated with the nonnative pathogen (i.e. 27% of genes). Although the two fungal pathogens did not differentially affect the amount of ectomycorrhizas, the fungal symbiont perceived their presence differently. The results may suggest that the symbiont has the ability to recognize a self/native and a nonself/nonnative pathogen, probably through host plant-mediated signal transduction. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  17. Positive feedback loop between introductions of non-native marine species and cultivation of oysters in Europe.

    Science.gov (United States)

    Mineur, Frederic; Le Roux, Auguste; Maggs, Christine A; Verlaque, Marc

    2014-12-01

    With globalization, agriculture and aquaculture activities are increasingly affected by diseases that are spread through movement of crops and stock. Such movements are also associated with the introduction of non-native species via hitchhiking individual organisms. The oyster industry, one of the most important forms of marine aquaculture, embodies these issues. In Europe disease outbreaks affecting cultivated populations of the naturalized oyster Crassostrea gigas caused a major disruption of production in the late 1960s and early 1970s. Mitigation procedures involved massive imports of stock from the species' native range in the northwestern Pacific from 1971 to 1977. We assessed the role stock imports played in the introduction of non-native marine species (including pathogens) from the northwestern Pacific to Europe through a methodological and critical appraisal of record data. The discovery rate of non-native species (a proxy for the introduction rate) from 1966 to 2012 suggests a continuous vector activity over the entire period. Disease outbreaks that have been affecting oyster production since 2008 may be a result of imports from the northwestern Pacific, and such imports are again being considered as an answer to the crisis. Although successful as a remedy in the short and medium terms, such translocations may bring new diseases that may trigger yet more imports (self-reinforcing or positive feedback loop) and lead to the introduction of more hitchhikers. Although there is a legal framework to prevent or reduce these introductions, existing procedures should be improved. © 2014 Society for Conservation Biology.

  18. Nonnative invasive plants in the Penobscot Experimental Forest in Maine, USA: influence of site, silviculture, and land use history

    Science.gov (United States)

    Elizabeth Olson; Laura S. Kenefic; Alison C. Dibble; John C. Brissette

    2011-01-01

    We investigated the occurrence of nonnative invasive plants on approximately 175 ha comprising a long-term, 60-year-old U.S. Forest Service silvicultural experiment and old-field stands in the Penobscot Experimental Forest (PEF) in central Maine. Stands in the silvicultural experiment were never cleared for agriculture, but have been repeatedly partially cut. Our...

  19. Modelling the introduction and spread of non-native species: international trade and climate change drive ragweed invasion.

    Science.gov (United States)

    Chapman, Daniel S; Makra, László; Albertini, Roberto; Bonini, Maira; Páldy, Anna; Rodinkova, Victoria; Šikoparija, Branko; Weryszko-Chmielewska, Elżbieta; Bullock, James M

    2016-09-01

    Biological invasions are a major driver of global change, for which models can attribute causes, assess impacts and guide management. However, invasion models typically focus on spread from known introduction points or non-native distributions and ignore the transport processes by which species arrive. Here, we developed a simulation model to understand and describe plant invasion at a continental scale, integrating repeated transport through trade pathways, unintentional release events and the population dynamics and local anthropogenic dispersal that drive subsequent spread. We used the model to simulate the invasion of Europe by common ragweed (Ambrosia artemisiifolia), a globally invasive plant that causes serious harm as an aeroallergen and crop weed. Simulations starting in 1950 accurately reproduced ragweed's current distribution, including the presence of records in climatically unsuitable areas as a result of repeated introduction. Furthermore, the model outputs were strongly correlated with spatial and temporal patterns of ragweed pollen concentrations, which are fully independent of the calibration data. The model suggests that recent trends for warmer summers and increased volumes of international trade have accelerated the ragweed invasion. For the latter, long distance dispersal because of trade within the invaded continent is highlighted as a key invasion process, in addition to import from the native range. Biosecurity simulations, whereby transport through trade pathways is halted, showed that effective control is only achieved by early action targeting all relevant pathways. We conclude that invasion models would benefit from integrating introduction processes (transport and release) with spread dynamics, to better represent propagule pressure from native sources as well as mechanisms for long-distance dispersal within invaded continents. Ultimately, such integration may facilitate better prediction of spatial and temporal variation in invasion

  20. Co-occurring nonnative woody shrubs have additive and non-additive soil legacies.

    Science.gov (United States)

    Kuebbing, Sara E; Patterson, Courtney M; Classen, Aimée T; Simberloff, Daniel

    2016-09-01

    To maximize limited conservation funds and prioritize management projects that are likely to succeed, accurate assessment of invasive nonnative species impacts is essential. A common challenge to prioritization is a limited knowledge of the difference between the impacts of a single nonnative species compared to the impacts of nonnative species when they co-occur, and in particular predicting when impacts of co-occurring nonnative species will be non-additive. Understanding non-additivity is important for management decisions because the management of only one co-occurring invader will not necessarily lead to a predictable reduction in the impact or growth of the other nonnative plant. Nonnative plants are frequently associated with changes in soil biotic and abiotic characteristics, which lead to plant-soil interactions that influence the performance of other species grown in those soils. Whether co-occurring nonnative plants alter soil properties additively or non-additively relative to their effects on soils when they grow in monoculture is rarely addressed. We use a greenhouse plant-soil feedback experiment to test for non-additive soil impacts of two common invasive nonnative woody shrubs, Lonicera maackii and Ligustrum sinense, in deciduous forests of the southeastern United States. We measured the performance of each nonnative shrub, a native herbaceous community, and a nonnative woody vine in soils conditioned by each shrub singly or together in polyculture. Soils conditioned by both nonnative shrubs had non-additive impacts on native and nonnative performance. Root mass of the native herbaceous community was 1.5 times lower and the root mass of the nonnative L. sinense was 1.8 times higher in soils conditioned by both L. maackii and L. sinense than expected based upon growth in soils conditioned by either shrub singly. This result indicates that when these two nonnative shrubs co-occur, their influence on soils disproportionally favors persistence

  1. Development of aquatic life criteria for triclosan and comparison of the sensitivity between native and non-native species.

    Science.gov (United States)

    Wang, Xiao-Nan; Liu, Zheng-Tao; Yan, Zhen-Guang; Zhang, Cong; Wang, Wei-Li; Zhou, Jun-Li; Pei, Shu-Wei

    2013-09-15

    Triclosan (TCS) is an antimicrobial agent which is used as a broad-spectrum bacteriostatic and found in personal care products, and due to this it is widely spread in the aquatic environment. However, there is no paper dealing with the aquatic life criteria of TCS, mainly result from the shortage of toxicity data of different taxonomic levels. In the present study, toxicity data were obtained from 9 acute toxicity tests and 3 chronic toxicity tests using 9 Chinese native aquatic species from different taxonomic levels, and the aquatic life criteria was derived using 3 methods. Furthermore, differences of species sensitivity distributions (SSD) between native and non-native species were compared. Among the tested species, demersal fish Misgurnus anguillicaudatus was the most sensitive species, and the fishes were more sensitive than the aquatic invertebrates of Annelid and insect, and the insect was the least sensitive species. The comparison showed that there was no significant difference between SSDs constructed from native and non-native taxa. Finally, a criterion maximum concentration of 0.009 mg/L and a criterion continuous concentration of 0.002 mg/L were developed based on different taxa, according to the U.S. Environmental Protection Agency guidelines. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. A new species of Oochoristica (Cyclophyllidea: Linstowiidae) from non-native Mediterranean geckos, Hemidactylus turcicus (Sauria: Gekkonidae), from Texas, USA.

    Science.gov (United States)

    McAllister, Chris T; Bursey, Charles R

    2017-06-01

    A new species of cyclophyllidean tapeworm, Oochoristica harschi sp. nov. is described from 2 of 18 (11%) non-native Mediterranean geckos (Hemidactylus turcicus) collected in June 2016 from Tom Green County, Texas, USA The new species has few characteristics in common with 17 species of Oochoristica previously described from Nearctic reptiles. Of this group, O. harschi is most similar to O. macallisteri Bursey and Goldberg, 1996 from the side-blotched lizard, Uta stansburiana from Arizona and California, USA, in number of testes, 14-20 vs. 12-20. However, O. harschi has oval suckers and a long neck compared to the circular suckers and absent neck in O. macallisteri. On comparison with other species of Oochoristica, it was found O. chinensis Jensen, Schmidt and Kuntz, 1983 from the Sino-Japanese realm, O. iguanae Bursey and Goldberg, 1996 from the Neotropical realm, and O. maccoyi Bursey and Goldberg, 1966 from the Panamanian realm were most similar to the new species. However, O. harschi can be differentiated by possessing a much longer neck and a shorter cirrus pouch. It can be further differentiated from O. chinensis by possessing an ovoid vs. an irregular vitellarium, from O. iguanae by having a smaller strobilus (65 vs. 110 mm) as well as an ovoid vs. a triangular vitellarium, and from O. maccoyi by having significantly more proglottids (145 vs. 89) and a longer strobilus (65 vs. 20 mm). The new species is the fifth species of Oochoristica reported from non-native H. turcicus and the 18th species described from the Nearctic region.

  3. Distribution and status of five non-native fish species in the Tampa Bay drainage (USA), a hot spot for fish introductions

    Science.gov (United States)

    Lawson, Katelyn M.; Tuckett, Quenton M.; Ritch, Jared L.; Nico, Leo; Fuller, Pam; Matheson, Richard E.; Hill, Jeffrey E.

    2017-01-01

    The Tampa Bay region of Florida (USA) is a hot spot for non-native freshwater fishes. However, published information on most non-native fishes in the basin is not current. Systematic sampling efforts targeting non-native fishes in the region were conducted from 2013–2015 by the University of Florida Tropical Aquaculture Laboratory. Data from these recent surveys were analyzed, along with historic and new data from published and unpublished sources, to assess current fish distributions and determine status. We focus on five of the non-native species sampled: pike killifish Belonesox belizanus Kner, 1860, green swordtail Xiphophorus hellerii Heckel, 1848, southern platyfish Xiphophorus maculatus (Günther, 1866), Mayan cichlid Mayaheros urophthalmus (Günther, 1862), and Jack Dempsey Rocio octofasciata (Regan, 1903). All five were found to have reproducing populations in the basin, each showing broader distributions than previously indicated. Non-native populations of four of the species have persisted in the Tampa Bay region since at least the 1990s. In contrast, the presence of Mayan cichlid in the basin was not confirmed until 2004. Based on numbers, distributions, and years of persistence, these five species all maintain established populations. Pike killifish and Mayan cichlid are established and spreading throughout multiple habitat types, while green swordtail, southern platyfish, and Jack Dempsey are localized and found primarily in more marginal habitats (e.g., small ditches and first order tributary streams). Factors affecting continued existence and distributions likely include aquaculture, biotic resistance, and thermal and salinity tolerances. We also clarify non-native species status determination using a multi-agency collaborative approach, and reconcile differences in terminology usage and interpretation.

  4. Vulnerability of freshwater native biodiversity to non-native ...

    Science.gov (United States)

    Background/Question/Methods Non-native species pose one of the greatest threats to native biodiversity. The literature provides plentiful empirical and anecdotal evidence of this phenomenon; however, such evidence is limited to local or regional scales. Employing geospatial analyses, we investigate the potential threat of non-native species to threatened and endangered aquatic animal taxa inhabiting unprotected areas across the continental US. We compiled distribution information from existing publicly available databases at the watershed scale (12-digit hydrologic unit code). We mapped non-native aquatic plant and animal species richness, and an index of cumulative invasion pressure, which weights non-native richness by the time since invasion of each species. These distributions were compared to the distributions of native aquatic taxa (fish, amphibians, mollusks, and decapods) from the International Union for the Conservation of Nature (IUCN) database. We mapped the proportion of species listed by IUCN as threatened and endangered, and a species rarity index per watershed. An overlay analysis identified watersheds experiencing high pressure from non-native species and also containing high proportions of threatened and endangered species or exhibiting high species rarity. Conservation priorities were identified by generating priority indices from these overlays and mapping them relative to the distribution of protected areas across the US. Results/Conclusion

  5. No universal scale-dependent impacts of invasive species on native plant species richness.

    Science.gov (United States)

    Stohlgren, Thomas J; Rejmánek, Marcel

    2014-01-01

    A growing number of studies seeking generalizations about the impact of plant invasions compare heavily invaded sites to uninvaded sites. But does this approach warrant any generalizations? Using two large datasets from forests, grasslands and desert ecosystems across the conterminous United States, we show that (i) a continuum of invasion impacts exists in many biomes and (ii) many possible species-area relationships may emerge reflecting a wide range of patterns of co-occurrence of native and alien plant species. Our results contradict a smaller recent study by Powell et al. 2013 (Science 339, 316-318. (doi:10.1126/science.1226817)), who compared heavily invaded and uninvaded sites in three biomes and concluded that plant communities invaded by non-native plant species generally have lower local richness (intercepts of log species richness-log area regression lines) but steeper species accumulation with increasing area (slopes of the regression lines) than do uninvaded communities. We conclude that the impacts of plant invasions on plant species richness are not universal.

  6. Loss of biodiversity in a conservation unit of the Brazilian Atlantic Forest: the effect of introducing non-native fish species

    Directory of Open Access Journals (Sweden)

    E. N. Fragoso-Moura

    Full Text Available Abstract The introduction of species has become an important problem for biodiversity and natural ecosystem conservation. The lake system of the middle Rio Doce (MG, Brazil comprises c. 200 lakes at various conservation states, of which 50 are located within the Rio Doce State Park (PERD. Previous studies had verified several of these lakes suffered non-native fishes introductions and the presence of these species needs for the implementation of actions aiming at not only their control but also the preservation of the native species. This study discusses the effects of non-native fish species in the largest conservation unit of Atlantic Forest in Minas Gerais, southeast of Brazil, using data from 1983 to 2010 distributed as follow: data prior to 2006 were obtained from previous studies, and data from September 2006 to July 2010 were obtained in Lake Carioca at four sampling stations using gillnets, seine nets and sieve. A total of 17 fish species was collected (2006-2010 of which five were introduced species. Among the small to medium size native species (30 to 2000 mm standard length seven had disappeared, two are new records and one was recaptured. The non-native species Cichla kelberi (peacock bass and Pygocentrus nattereri (red piranha are within the most abundant captured species. Integrated with other actions, such as those preventing new introductions, a selective fishing schedule is proposed as an alternative approach to improve the conservation management actions and the local and regional biodiversity maintenance.

  7. Loss of biodiversity in a conservation unit of the Brazilian Atlantic Forest: the effect of introducing non-native fish species.

    Science.gov (United States)

    Fragoso-Moura, E N; Oporto, L T; Maia-Barbosa, P M; Barbosa, F A R

    2016-02-01

    The introduction of species has become an important problem for biodiversity and natural ecosystem conservation. The lake system of the middle Rio Doce (MG, Brazil) comprises c. 200 lakes at various conservation states, of which 50 are located within the Rio Doce State Park (PERD). Previous studies had verified several of these lakes suffered non-native fishes introductions and the presence of these species needs for the implementation of actions aiming at not only their control but also the preservation of the native species. This study discusses the effects of non-native fish species in the largest conservation unit of Atlantic Forest in Minas Gerais, southeast of Brazil, using data from 1983 to 2010 distributed as follow: data prior to 2006 were obtained from previous studies, and data from September 2006 to July 2010 were obtained in Lake Carioca at four sampling stations using gillnets, seine nets and sieve. A total of 17 fish species was collected (2006-2010) of which five were introduced species. Among the small to medium size native species (30 to 2000 mm standard length) seven had disappeared, two are new records and one was recaptured. The non-native species Cichla kelberi (peacock bass) and Pygocentrus nattereri (red piranha) are within the most abundant captured species. Integrated with other actions, such as those preventing new introductions, a selective fishing schedule is proposed as an alternative approach to improve the conservation management actions and the local and regional biodiversity maintenance.

  8. The nature of plant species.

    Science.gov (United States)

    Rieseberg, Loren H; Wood, Troy E; Baack, Eric J

    2006-03-23

    Many botanists doubt the existence of plant species, viewing them as arbitrary constructs of the human mind, as opposed to discrete, objective entities that represent reproductively independent lineages or 'units of evolution'. However, the discreteness of plant species and their correspondence with reproductive communities have not been tested quantitatively, allowing zoologists to argue that botanists have been overly influenced by a few 'botanical horror stories', such as dandelions, blackberries and oaks. Here we analyse phenetic and/or crossing relationships in over 400 genera of plants and animals. We show that although discrete phenotypic clusters exist in most genera (> 80%), the correspondence of taxonomic species to these clusters is poor (< 60%) and no different between plants and animals. Lack of congruence is caused by polyploidy, asexual reproduction and over-differentiation by taxonomists, but not by contemporary hybridization. Nonetheless, crossability data indicate that 70% of taxonomic species and 75% of phenotypic clusters in plants correspond to reproductively independent lineages (as measured by postmating isolation), and thus represent biologically real entities. Contrary to conventional wisdom, plant species are more likely than animal species to represent reproductively independent lineages.

  9. Impacts of Climate Variability on Non-native Plant Invasion in the Western U.S.

    Science.gov (United States)

    Bradley, B. A.

    2006-12-01

    Plant invasions are changing ecosystem structure and function throughout the United States. In many areas of the west, invasive species such as tamarisk (Tamarix spp.), cheatgrass (Bromus tectorum), and yellow starthistle (Centaurea solstitialis) dominate landscapes. Expansion of these species is occurring at a staggering rate, and invasion rates may change in the future as native ecosystems become more or less susceptible to invasion because of changes in climate. For example, evidence suggests that some plant invaders are favored under increased ambient CO2 levels, potentially leading to increased invasion with continued greenhouse gas emissions. In this work, I predict how western invasive plant species may also be affected by changes in climate variability. According to IPCC reports, rising ocean temperatures may change the frequency and intensity of El Niño events, potentially resulting in wetter El Niño years and/or more extreme and lengthier drought. In semi-arid systems, changing frequency or magnitude of extreme weather events may further shift the competitive balance between native and invasive species. For example, cheatgrass and yellow starthistle, both annual invaders, display high inter-annual variability in response to water availability. As a result, plants are larger and produce more seeds than native competitors during extreme wet years. This phenological response is so strong in cheatgrass communities that it can be observed in regional satellite records. Further, dense cheatgrass growth leads to a secondary feedback in the form of wildfire; higher density cheatgrass increases fire frequency in shrublands and enables further cheatgrass colonization. In this work, I synthesize knowledge of invasive plant phenological response under different climate conditions, drawing on information gathered through geographical mapping efforts at state or regional levels by university and agency researchers. Using the ranges of climate tolerance from current

  10. Species interactions and plant polyploidy.

    Science.gov (United States)

    Segraves, Kari A; Anneberg, Thomas J

    2016-07-01

    Polyploidy is a common mode of speciation that can have far-reaching consequences for plant ecology and evolution. Because polyploidy can induce an array of phenotypic changes, there can be cascading effects on interactions with other species. These interactions, in turn, can have reciprocal effects on polyploid plants, potentially impacting their establishment and persistence. Although there is a wealth of information on the genetic and phenotypic effects of polyploidy, the study of species interactions in polyploid plants remains a comparatively young field. Here we reviewed the available evidence for how polyploidy may impact many types of species interactions that range from mutualism to antagonism. Specifically, we focused on three main questions: (1) Does polyploidy directly cause the formation of novel interactions not experienced by diploids, or does it create an opportunity for natural selection to then form novel interactions? (2) Does polyploidy cause consistent, predictable changes in species interactions vs. the evolution of idiosyncratic differences? (3) Does polyploidy lead to greater evolvability in species interactions? From the scarce evidence available, we found that novel interactions are rare but that polyploidy can induce changes in pollinator, herbivore, and pathogen interactions. Although further tests are needed, it is likely that selection following whole-genome duplication is important in all types of species interaction and that there are circumstances in which polyploidy can enhance the evolvability of interactions with other species. © 2016 Botanical Society of America.

  11. 77 FR 57647 - Endangered and Threatened Wildlife and Plants; Endangered Status for 23 Species on Oahu and...

    Science.gov (United States)

    2012-09-18

    ... habitats, primarily from introduced ungulates, such as feral pigs and goats, and the spread of nonnative plants. Six of these species face threats from habitat destruction and modification from fire. Fourteen... loss due to agriculture and urban development, from stream diversion and channelization, and by...

  12. The Public and Professionals Reason Similarly about the Management of Non-Native Invasive Species: A Quantitative Investigation of the Relationship between Beliefs and Attitudes

    Science.gov (United States)

    Fischer, Anke; Selge, Sebastian; van der Wal, René; Larson, Brendon M. H.

    2014-01-01

    Despite continued critique of the idea of clear boundaries between scientific and lay knowledge, the ‘deficit-model’ of public understanding of ecological issues still seems prevalent in discourses of biodiversity management. Prominent invasion biologists, for example, still argue that citizens need to be educated so that they accept scientists’ views on the management of non-native invasive species. We conducted a questionnaire-based survey with members of the public and professionals in invasive species management (n = 732) in Canada and the UK to investigate commonalities and differences in their perceptions of species and, more importantly, how these perceptions were connected to attitudes towards species management. Both native and non-native mammal and tree species were included. Professionals tended to have more extreme views than the public, especially in relation to nativeness and abundance of a species. In both groups, species that were perceived to be more abundant, non-native, unattractive or harmful to nature and the economy were more likely to be regarded as in need of management. While perceptions of species and attitudes towards management thus often differed between public and professionals, these perceptions were linked to attitudes in very similar ways across the two groups. This suggests that ways of reasoning about invasive species employed by professionals and the public might be more compatible with each other than commonly thought. We recommend that managers and local people engage in open discussion about each other’s beliefs and attitudes prior to an invasive species control programme. This could ultimately reduce conflict over invasive species control. PMID:25170957

  13. Spatio-temporal segregation and size distribution of fish assemblages as related to non-native species occurrence in the middle rio Doce Valley, MG, Brazil

    Directory of Open Access Journals (Sweden)

    Henrique Corrêa Giacomini

    Full Text Available The lakes in the middle rio Doce Valley (MG are suffering impacts due to the introduction of invasive fish species, mainly piscivorous species like red piranha Pygocentrus nattereri and peacock bass Cichla kelberi. Fishes were collected in bimonthly samples conducted at ten lakes along a year. The present study showed that the composition of native fish assemblages is significantly related to the presence and type of non-native species. Fish species distribution among lakes can be explained by differences in species body size: smaller native species are less concentrated in lakes with invasive piscivores, which is in accordance with the hypothesis that they have greater susceptibility to predation by invaders. Another probable cause for this correlation is the proximity of lakes to the drainage system, which could explain both the non-native incidence and the turnover of native species composition. Furthermore, temporal variability in species composition was significantly higher in invaded lakes. This last factor may be linked to seasonal flood pulses, which carry immigrant fishes from streams in the vicinity. The metacommunity framework can bring insights for future studies in such spatially structured systems, and the approach should improve our understanding of processes underlying species composition as well as help direct conservation-focused management plans.

  14. Current status of non-native fish species in the St. Louis River estuary

    Science.gov (United States)

    The fish community of the St. Louis River estuary is well characterized, thanks to fishery assessment and invasive species early detection monitoring by federal, state, and tribal agencies. This sampling includes long-standing adult/juvenile fish surveys, larval fish surveys beg...

  15. COMPARISON OF ANNUAL PRODUCTION ECOLOGY OF NATIVE EELGRASS ZOSTERA MARINA AND THE NON-NATIVE DWARF EELGRASS Z. JAPONICA IN YAQUINA BAY, OREGON

    Science.gov (United States)

    When non-native plant species invade a system they often change patterns of primary production. I evaluate the contribution of the seagrass Zostera marina and it's non-native congener Z. japonica to primary production in Yaquina Bay. Few measurements of Z. japonica production e...

  16. Assessing the impact of non-native freshwater fishes on native species using relative weight

    Directory of Open Access Journals (Sweden)

    Giannetto D.

    2012-01-01

    Full Text Available The aim of the research was to test relative weight (Wr, a condition index which allows evaluation of fish well-being, as a tool to investigate the impact of the presence of non native species (NNS on the condition of the key native species (NS of the Tiber River basin (Italy: Barbustyberinus Bonaparte, Leuciscus cephalus (Linnaeus, Leuciscus lucumonis Bianco, Rutilus rubilio (Bonaparte and Telestes muticellus (Bonaparte. By means of Canonical Correlation Analysis, data from 130 sampling sites, distributed throughout Tiber River basin, were examined. Wr of NS was related to densities of NNS and to environmental variables. Moreover, the correlation between Wr of NS and density of NNS was investigated through linear regression analysis and covariance analysis. Preliminary results encourage the use of Wr as a tool to assess the relationship between NS and ecological factors (such as the presence of NNS and to explain the changes that occur along the longitudinal gradient of a river.

  17. Non-native fish introductions in the Czech Republic – species inventory, facts and future perspectives

    Czech Academy of Sciences Publication Activity Database

    Musil, J.; Jurajda, Pavel; Adámek, Z.; Horký, P.; Slavík, O.

    2010-01-01

    Roč. 26, Suppl. 2 (2010), s. 38-45 ISSN 0175-8659. [International Conference and Workshop on Managing Alien Species for Sustainable Development of Aquaculture and Fisheries. Florence, 05.11.2008-07.11.2008] Institutional research plan: CEZ:AV0Z60930519 Keywords : freshwater fish * fisheries management * invasion success Subject RIV: EH - Ecology, Behaviour Impact factor: 0.945, year: 2010

  18. Contrasting patterns of herbivore and predator pressure on invasive and native plants

    NARCIS (Netherlands)

    Engelkes, T.; Wouters, B.; Bezemer, T.M.; Harvey, J.A.; Putten, van der W.H.

    2012-01-01

    Invasive non-native plant species often harbor fewer herbivorous insects than related native plant species. However, little is known about how herbivorous insects on non-native plants are exposed to carnivorous insects, and even less is known on plants that have recently expanded their ranges within

  19. Invasive plants in 21st Century landscapes.

    Science.gov (United States)

    Valerie. Rapp

    2005-01-01

    A plant species is defined as invasive if it is nonnative to the ecosystem under consideration, and if it causes or is likely to cause economic or environmental harm or harm to human health. Nonnative plant invasions are generally considered to have reached the Pacific Northwest in the mid-1800s with the arrival of European-American settlers. Invasive species such as...

  20. When Anthropogenic River Disturbance Decreases Hybridisation between Non-Native and Endemic Cyprinids and Drives an Ecomorphological Displacement towards Juvenile State in Both Species.

    Directory of Open Access Journals (Sweden)

    Emmanuel Corse

    Full Text Available Understanding the impact of non-native species on native species is a major challenge in molecular ecology, particularly for genetically compatible fish species. Invasions are generally difficult to study because their effects may be confused with those of environmental or human disturbances. Colonized ecosystems are differently impacted by human activities, resulting in diverse responses and interactions between native and non-native species. We studied the dynamics between two Cyprinids species (invasive Chondrostoma nasus and endemic Parachondrostoma toxostoma and their hybrids in 16 populations (from allopatric to sympatric situations and from little to highly fragmented areas corresponding to 2,256 specimens. Each specimen was assigned to a particular species or to a hybrid pool using molecular identification (cytochrome b and 41 microsatellites. We carried out an ecomorphological analysis based on size, age, body shape, and diet (gut vacuity and molecular fecal contents. Our results contradicted our initial assumptions on the pattern of invasion and the rate of introgression. There was no sign of underperformance for the endemic species in areas where hybridisation occurred. In the unfragmented zone, the introduced species was found mostly downstream, with body shapes similar to those in allopatric populations while both species were found to be more insectivorous than the reference populations. However, high level of hybridisation was detected, suggesting interactions between the two species during spawning and/or the existence of hybrid swarm. In the disturbed zone, introgression was less frequent and slender body shape was associated with diatomivorous behaviour, smaller size (juvenile characteristics and greater gut vacuity. Results suggested that habitat degradation induced similar ecomorphological trait changes in the two species and their hybrids (i.e. a transition towards a pedomorphic state where the invasive species is more

  1. Density-dependent effects of non-native brown trout Salmo trutta on the species-area relationship in stream fish assemblages.

    Science.gov (United States)

    Hasegawa, K; Mori, T; Yamazaki, C

    2017-01-01

    The spatial scale and density-dependent effects of non-native brown trout Salmo trutta on species richness of fish assemblages were examined at 48 study sites in Mamachi Stream, a tributary of Chitose River, Hokkaido, Japan. The density of age ≥1 year S. trutta was high in the upstream side of the main stem of Mamachi Stream. Fish species richness increased with increasing area of study sites (habitat size), but the increasing magnitude of the species richness with area decreased with increasing age of ≥1 year S. trutta density. The relationships between age ≥1 year S. trutta, however, and presence-absence of each species seemed to be different among species. Species richness was also determined by location and physical environmental variables, i.e. it was high on the downstream side and in structurally complex environments. © 2016 The Fisheries Society of the British Isles.

  2. Plant species richness and abundance in residential yards across a tropical watershed: implications for urban sustainability

    Directory of Open Access Journals (Sweden)

    Cristina P. Vila-Ruiz

    2014-09-01

    Full Text Available Green spaces within residential areas provide important contributions to the sustainability of urban systems. Therefore, studying the characteristics of these areas has become a research priority in cities worldwide. This project evaluated various aspects of the plant biodiversity of residential yards (i.e., front yards and back yards within the Río Piedras watershed in the San Juan metropolitan area of Puerto Rico. Our work included gathering information on vegetation composition and abundance of woody species (i.e., trees, shrubs, palms, ferns and large herbs (>2 m height, species origin (native vs. introduced, and species uses (ornamental, food, and medicinal plants. A total of 424 yards were surveyed within an area of 187,191 m². We found 383 woody species, with shrubs being the most abundant plant habitat. As expected, residential yards hosted a disproportionate amount of introduced species (69.5%. The most common shrub species were all non-native ornamentals, whereas the most common tree species included food trees as well as ornamental plants and two native species. Front yards hosted more ornamental species per unit area than backyards, while the latter had more food plants. The high amount of introduced species may present a challenge in terms of implementation of plant conservation initiatives if there is no clear definition of urban conservation goals. On the other hand, the high frequency of yards containing food plants may facilitate the development of residential initiatives that could provide future adaptive capacity to food shortages.

  3. Impact of water regimes on an experimental community of four desert arbuscular mycorrhizal fungal (AMF) species, as affected by the introduction of a non-native AMF species.

    Science.gov (United States)

    Symanczik, Sarah; Courty, Pierre-Emmanuel; Boller, Thomas; Wiemken, Andres; Al-Yahya'ei, Mohamed N

    2015-11-01

    Field studies have revealed the impact of changing water regimes on the structure of arbuscular mycorrhizal fungal (AMF) communities, but it is not known what happens to the abundance of individual AMF species within the community when the water conditions in the rhizosphere change. The behavior of four AMF species isolated from the Arabian desert (Diversispora aurantia, Diversispora omaniana, Septoglomus africanum, and an undescribed Paraglomus species) was investigated when assembled in microcosms containing Sorghum bicolor as host plant, and treated with various water regimes. Furthermore, the impact of invasion of these assemblages by Rhizophagus irregularis, an AMF species widely used in commercial inocula, was studied. The abundance of each AMF species in sorghum roots was measured by determining the transcript numbers of their large ribosomal subunit (rLSU) by real-time PCR, using cDNA and species-specific primers. Plant biomass and length of AMF extraradical hyphae were also measured. The abundance of each AMF species within the sorghum roots was influenced by both the water regime and the introduction of R. irregularis. Under dry conditions, the introduction of R. irregularis reduced the total abundance of all native AMF species in roots and also led to a reduction in the amount of extraradical mycelium, as well as to a partial decrease in plant biomass. The results indicate that both water regime and the introduction of an invasive AMF species can strongly alter the structure of an AMF native assemblage with a consequent impact on the entire symbiotic mycorrhizal relationship.

  4. Non-native fishes in Florida freshwaters: a literature review and synthesis

    Science.gov (United States)

    Schofield, Pamela J.; Loftus, William F.

    2015-01-01

    Non-native fishes have been known from freshwater ecosystems of Florida since the 1950s, and dozens of species have established self-sustaining populations. Nonetheless, no synthesis of data collected on those species in Florida has been published until now. We searched the literature for peer-reviewed publications reporting original data for 42 species of non-native fishes in Florida that are currently established, were established in the past, or are sustained by human intervention. Since the 1950s, the number of non-native fish species increased steadily at a rate of roughly six new species per decade. Studies documented (in decreasing abundance): geographic location/range expansion, life- and natural-history characteristics (e.g., diet, habitat use), ecophysiology, community composition, population structure, behaviour, aquatic-plant management, and fisheries/aquaculture. Although there is a great deal of taxonomic uncertainty and confusion associated with many taxa, very few studies focused on clarifying taxonomic ambiguities of non-native fishes in the State. Most studies were descriptive; only 15 % were manipulative. Risk assessments, population-control studies and evaluations of effects of non-native fishes were rare topics for research, although they are highly valued by natural-resource managers. Though some authors equated lack of data with lack of effects, research is needed to confirm or deny conclusions. Much more is known regarding the effects of lionfish (Pterois spp.) on native fauna, despite its much shorter establishment time. Natural-resource managers need biological and ecological information to make policy decisions regarding non-native fishes. Given the near-absence of empirical data on effects of Florida non-native fishes, and the lengthy time-frames usually needed to collect such information, we provide suggestions for data collection in a manner that may be useful in the evaluation and prediction of non-native fish effects.

  5. Invasive plant species in hardwood tree plantations

    Science.gov (United States)

    Rochelle R. Beasley; Paula M. Pijut

    2010-01-01

    Invasive plants are species that can grow and spread aggressively, mature quickly, and invade an ecosystem causing economic and environmental damage. Invasive plants usually invade disturbed areas, but can also colonize small areas quickly, and may spread and dominate large areas in a few short years. Invasive plant species displace native or desirable forest...

  6. Do invasive plant species alter soil health?

    Science.gov (United States)

    Invasive species may alter soil characteristics or interact with the soil microbial community to yield a competitive advantage. Our objectives were to determine: if invasive plant species alter soil properties important to soil health; and the long-term effects of invasive plant species on soil pro...

  7. Changes in the Pincate Reserve ecosystems: Invasion of non-native plants

    Science.gov (United States)

    Denise Z. Avila-Jimenez

    2005-01-01

    Over the years, humans have modified the Sonoran Desert by introducing invasive plants that prosper in disturbed and non-disturbed habitats. These invaders modify the dynamics and structure of populations and the composition of communities, which in turn can result in radical changes in wildlife habitat. The natural landscape of the Sonoran Desert is characterized by...

  8. The Effects of Anthropogenic Structures on Habitat Connectivity and the Potential Spread of Non-Native Invertebrate Species in the Offshore Environment.

    Science.gov (United States)

    Simons, Rachel D; Page, Henry M; Zaleski, Susan; Miller, Robert; Dugan, Jenifer E; Schroeder, Donna M; Doheny, Brandon

    2016-01-01

    Offshore structures provide habitat that could facilitate species range expansions and the introduction of non-native species into new geographic areas. Surveys of assemblages of seven offshore oil and gas platforms in the Santa Barbara Channel revealed a change in distribution of the non-native sessile invertebrate Watersipora subtorquata, a bryozoan with a planktonic larval duration (PLD) of 24 hours or less, from one platform in 2001 to four platforms in 2013. We use a three-dimensional biophysical model to assess whether larval dispersal via currents from harbors to platforms and among platforms is a plausible mechanism to explain the change in distribution of Watersipora and to predict potential spread to other platforms in the future. Hull fouling is another possible mechanism to explain the change in distribution of Watersipora. We find that larval dispersal via currents could account for the increase in distribution of Watersipora from one to four platforms and that Watersipora is unlikely to spread from these four platforms to additional platforms through larval dispersal. Our results also suggest that larvae with PLDs of 24 hours or less released from offshore platforms can attain much greater dispersal distances than larvae with PLDs of 24 hours or less released from nearshore habitat. We hypothesize that the enhanced dispersal distance of larvae released from offshore platforms is driven by a combination of the offshore hydrodynamic environment, larval behavior, and larval release above the seafloor.

  9. Conservation and restoration of forest trees impacted by non-native pathogens: the role of genetics and tree improvement

    Science.gov (United States)

    R.A. Sniezko; L.A. Winn

    2017-01-01

    North American native tree species in forest ecosystems, as well as managed forests and urban plantings, are being severely impacted by pathogens and insects. The impacts of these pathogens and insects often increase over time, and they are particularly acute for those species affected by non-native pathogens and insects. For restoration of affected tree species or for...

  10. Nest-location and nest-survival of black-chinned hummingbirds in New Mexico: A comparison between rivers with differing levels of regulation and invasion of nonnative plants

    Science.gov (United States)

    D. Max Smith; Deborah M. Finch; Scott H. Stoleson

    2014-01-01

    We compared plants used as sites for nests and survival of nests of black-chinned hummingbirds (Archilochus alexandri) along two rivers in New Mexico. Along the free-flowing Gila River which was dominated by native plants, most nests were constructed in boxelder (Acer negundo). Along the flow-restricted Middle Rio Grande which was dominated by nonnative plants, most...

  11. Non-native molluscan colonizers on deliberately placed shipwrecks in the Florida Keys, with description of a new species of potentially invasive worm-snail (Gastropoda: Vermetidae

    Directory of Open Access Journals (Sweden)

    Rüdiger Bieler

    2017-04-01

    Full Text Available Artificial reefs created by deliberately sinking ships off the coast of the Florida Keys island chain are providing new habitat for marine invertebrates. This newly developing fouling community includes the previously reported invasive orange tube coral Tubastraea coccinea and the non-native giant foam oyster Hyotissa hyotis. New SCUBA-based surveys involving five shipwrecks spanning the upper, middle, and lower Florida Keys, show T. coccinea now also established in the lower Keys and H. hyotis likewise extending to new sites. Two additional mollusks found on the artificial reefs, the amathinid gastropod Cyclothyca pacei and gryphaeid oyster Hyotissa mcgintyi, the latter also common in the natural reef areas, are discussed as potentially non-native. A new species of sessile, suspension-feeding, worm-snail, Thylacodes vandyensis Bieler, Rawlings & Collins n. sp. (Vermetidae, is described from the wreck of the USNS Vandenberg off Key West and discussed as potentially invasive. This new species is compared morphologically and by DNA barcode markers to other known members of the genus, and may be a recent arrival from the Pacific Ocean. Thylacodes vandyensis is polychromatic, with individuals varying in both overall head-foot coloration and mantle margin color pattern. Females brood stalked egg capsules attached to their shell within the confines of their mantle cavity, and give rise to crawl-away juveniles. Such direct-developing species have the demonstrated capacity for colonizing habitats isolated far from their native ranges and establishing rapidly growing founder populations. Vermetid gastropods are common components of the marine fouling community in warm temperate and tropical waters and, as such, have been tagged as potentially invasive or with a high potential to be invasive in the Pacific Ocean. As vermetids can influence coral growth/composition in the Pacific and have been reported serving as intermediate hosts for blood flukes of

  12. Endangered Species (Plants). LC Science Tracer Bullet.

    Science.gov (United States)

    Niskern, Diana, Comp.

    This guide is intended for those who wish to study the literature dealing with various aspects of endangered plant species. This document includes the following sections, some of which are bibliographies: (1) "Introductions to the Topic"; (2) "Subject Headings" (for endangered species of plants used by the Library of Congress); (3) "General…

  13. The Invasive Plant Species Education Guide

    Science.gov (United States)

    Mason, Kevin; James, Krista; Carlson, Kitrina; D'Angelo, Jean

    2010-01-01

    To help high school students gain a solid understanding of invasive plant species, university faculty and students from the University of Wisconsin-Stout (UW-Stout) and a local high school teacher worked together to develop the Invasive Plant Species (IPS) Education Guide. The IPS Education Guide includes nine lessons that give students an…

  14. Protected-area boundaries as filters of plant invasions.

    Science.gov (United States)

    Foxcroft, Llewellyn C; Jarošík, Vojtěch; Pyšek, Petr; Richardson, David M; Rouget, Mathieu

    2011-04-01

    Human land uses surrounding protected areas provide propagules for colonization of these areas by non-native species, and corridors between protected-area networks and drainage systems of rivers provide pathways for long-distance dispersal of non-native species. Nevertheless, the influence of protected-area boundaries on colonization of protected areas by invasive non-native species is unknown. We drew on a spatially explicit data set of more than 27,000 non-native plant presence records for South Africa's Kruger National Park to examine the role of boundaries in preventing colonization of protected areas by non-native species. The number of records of non-native invasive plants declined rapidly beyond 1500 m inside the park; thus, we believe that the park boundary limited the spread of non-native plants. The number of non-native invasive plants inside the park was a function of the amount of water runoff, density of major roads, and the presence of natural vegetation outside the park. Of the types of human-induced disturbance, only the density of major roads outside the protected area significantly increased the number of non-native plant records. Our findings suggest that the probability of incursion of invasive plants into protected areas can be quantified reliably. ©2010 Society for Conservation Biology.

  15. 78 FR 75313 - Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition To Reclassify...

    Science.gov (United States)

    2013-12-11

    ... the removal or reduction of the Act's protections. A species is an ``endangered species'' for purposes... invasive, nonnative plant species was not identified as a specific threat to E. altissimum in the 1994... and its habitat. The primary invasive, nonnative species of concern is Ehrharta calycina, a perennial...

  16. Why some plant species are rare.

    Science.gov (United States)

    Wieger Wamelink, G W; Wamelink, G W Weiger; Goedhart, Paul W; Frissel, Joep; Frissel, Josep Y

    2014-01-01

    Biodiversity, including plant species diversity, is threatened worldwide as a result of anthropogenic pressures such as an increase of pollutants and climate change. Rare species in particular are on the verge of becoming extinct. It is still unclear as to why some plant species are rare and others are not. Are they rare due to: intrinsic reasons, dispersal capacity, the effects of management or abiotic circumstances? Habitat preference of rare plant species may play an important role in determining why some species are rare. Based on an extensive data set of soil parameters we investigated if rarity is due to a narrow habitat preference for abiotic soil parameters. For 23 different abiotic soil parameters, of which the most influential were groundwater-table, soil-pH and nutrient-contents, we estimated species responses for common and rare species. Based on the responses per species we calculated the range of occurrence, the range between the 5 and 95 percentile of the response curve giving the habitat preference. Subsequently, we calculated the average response range for common and rare species. In addition, we designed a new graphic in order to provide a better means for presentation of the results. The habitat preferences of rare species for abiotic soil conditions are significantly narrower than for common species. Twenty of the twenty-three abiotic parameters showed on average significantly narrower habitat preferences for rare species than for common species; none of the abiotic parameters showed on average a narrower habitat preference for common species. The results have major implications for the conservation of rare plant species; accordingly management and nature development should be focussed on the maintenance and creation of a broad range of environmental conditions, so that the requirements of rare species are met. The conservation of (abiotic) gradients within ecosystems is particularly important for preserving rare species.

  17. Ecohydrological consequences of non-native riparian vegetation in the southwestern United States: A review from an ecophysiological perspective

    Science.gov (United States)

    Hultine, K. R.; Bush, S. E.

    2011-07-01

    Protecting water resources for expanding human enterprise while conserving valued natural habitat is among the greatest challenges of the 21st century. Global change processes such as climate change and intensive land use pose significant threats to water resources, particularly in arid regions where potential evapotranspiration far exceeds annual rainfall. Potentially compounding these shortages is the progressive expansion of non-native plant species in riparian areas along streams, canals and rivers in geographically arid regions. This paper sets out to identify when and where non-native riparian plant species are likely to have the highest potential impact on hydrologic fluxes of arid and semiarid river systems. We develop an ecophysiological framework that focuses on two main criteria: (1) examination of the physiological traits that promote non-native species establishment and persistence across environmental gradients, and (2) assessment of where and to what extent hydrologic fluxes are potentially altered by the establishment of introduced species at varying scales from individual plants, to small river reaches, to entire river basins. We highlight three non-native plant species that currently dominate southwestern United States riparian forests. These include tamarisk (Tamarix spp.), Russian olive (Eleagnus angustifolia), and Russian knapweed (Acroptilon repens). As with other recent reviews, we suspect that in many cases the removal of these, and other non-native species will have little or no impact on either streamflow volume or groundwater levels. However, we identify potential exceptions where the expansion of non-native plant species could have significant impact on ecohydrologic processes associated with southwestern United States river systems. Future research needs are outlined that will ultimately assist land managers and policy makers with restoration and conservation priorities to preserve water resources and valued riparian habitat given

  18. Integrating early detection with DNA barcoding: species identification of a non-native monitor lizard (Squamata: Varanidae) carcass in Mississippi, U.S.A.

    Science.gov (United States)

    Reed, Robert N.; Hopken, Matthew W.; Steen, David A.; Falk, Bryan G.; Piaggio, Antoinette J.

    2016-01-01

    Early detection of invasive species is critical to increasing the probability of successful management. At the primary stage of an invasion, invasive species are easier to control as the population is likely represented by just a few individuals. Detection of these first few individuals can be challenging, particularly if they are cryptic or otherwise characterized by low detectability. The engagement of members of the public may be critical to early detection as there are far more citizen s on the landscape than trained biologists. However, it can be difficult to assess the credibility of public reporting, especially when a diagnostic digital image or a physical specimen in good condition are lacking. DNA barcoding can be used for verification when morphological identification of a specimen is not possible or uncertain (i.e., degraded or partial specimen). DNA barcoding relies on obtaining a DNA sequence from a relatively small fragment of mitochondrial DNA and comparing it to a database of sequences containing a variety of expertly identified species. He rein we report the successful identification of a degraded specimen of a non-native, potentially invasive reptile species (Varanus niloticus) via DNA barcoding, after discovery and reporting by a member of the public.

  19. Ecological disequilibrium drives insect pest and pathogen accumulation in non-native trees.

    Science.gov (United States)

    Crous, Casparus J; Burgess, Treena I; Le Roux, Johannes J; Richardson, David M; Slippers, Bernard; Wingfield, Michael J

    2016-12-23

    Non-native trees have become dominant components of many landscapes, including urban ecosystems, commercial forestry plantations, fruit orchards, and as invasives in natural ecosystems. Often, these trees have been separated from their natural enemies (i.e. insects and pathogens) leading to ecological disequilibrium, that is, the immediate breakdown of historically co-evolved interactions once introduced into novel environments. Long-established, non-native tree plantations provide useful experiments to explore the dimensions of such ecological disequilibria. We quantify the status quo of non-native insect pests and pathogens catching up with their tree hosts (planted Acacia, Eucalyptus and Pinus species) in South Africa, and examine which native South African enemy species utilise these trees as hosts. Interestingly, pines, with no confamilial relatives in South Africa and the longest residence time (almost two centuries), have acquired only one highly polyphagous native pathogen. This is in contrast to acacias and eucalypts, both with many native and confamilial relatives in South Africa that have acquired more native pathogens. These patterns support the known role of phylogenetic relatedness of non-native and native floras in influencing the likelihood of pathogen shifts between them. This relationship, however, does not seem to hold for native insects. Native insects appear far more likely to expand their feeding habits onto non-native tree hosts than are native pathogens, although they are generally less damaging. The ecological disequilibrium conditions of non-native trees are deeply rooted in the eco-evolutionary experience of the host plant, co-evolved natural enemies, and native organisms from the introduced range. We should expect considerable spatial and temporal variation in ecological disequilibrium conditions among non-native taxa, which can be significantly influenced by biosecurity and management practices. Published by Oxford University Press on

  20. Assessing plant community composition fails to capture impacts of white-tailed deer on native and invasive plant species.

    Science.gov (United States)

    Nuzzo, Victoria; Dávalos, Andrea; Blossey, Bernd

    2017-07-01

    Excessive herbivory can have transformative effects on forest understory vegetation, converting diverse communities into depauperate ones, often with increased abundance of non-native plants. White-tailed deer are a problematic herbivore throughout much of eastern North America and alter forest understory community structure. Reducing (by culling) or eliminating (by fencing) deer herbivory is expected to return understory vegetation to a previously diverse condition. We examined this assumption from 1992 to 2006 at Fermilab (Batavia, IL) where a cull reduced white-tailed deer ( Odocoileus virginianus ) abundance in 1998/1999 by 90 % from 24.6 to 2.5/km 2 , and at West Point, NY, where we assessed interactive effects of deer, earthworms, and invasive plants using 30 × 30 m paired fenced and open plots in 12 different forests from 2009 to 2012. We recorded not only plant community responses (species presence and cover) within 1 m 2 quadrats, but also responses of select individual species (growth, reproduction). At Fermilab, introduced Alliaria petiolata abundance initially increased as deer density increased, but then declined after deer reduction. The understory community responded to the deer cull by increased cover, species richness and height, and community composition changed but was dominated by early successional native forbs. At West Point plant community composition was affected by introduced earthworm density but not deer exclusion. Native plant cover increased and non-native plant cover decreased in fenced plots, thus keeping overall plant cover similar. At both sites native forb cover increased in response to deer reduction, but the anticipated response of understory vegetation failed to materialize at the community level. Deer-favoured forbs ( Eurybia divaricata , Maianthemum racemosum , Polygonatum pubescens and Trillium recurvatum ) grew taller and flowering probability increased in the absence of deer. Plant community monitoring fails to capture

  1. Estimating Invasion Success by Non-Native Trees in a National Park Combining WorldView-2 Very High Resolution Satellite Data and Species Distribution Models

    Directory of Open Access Journals (Sweden)

    Antonio T. Monteiro

    2017-01-01

    Full Text Available Invasion by non-native tree species is an environmental and societal challenge requiring predictive tools to assess invasion dynamics. The frequent scale mismatch between such tools and on-ground conservation is currently limiting invasion management. This study aimed to reduce these scale mismatches, assess the success of non-native tree invasion and determine the environmental factors associated to it. A hierarchical scaling approach combining species distribution models (SDMs and satellite mapping at very high resolution (VHR was developed to assess invasion by Acacia dealbata in Peneda-Gerês National Park, the only national park in Portugal. SDMs were first used to predict the climatically suitable areas for A. dealdata and satellite mapping with the random-forests classifier was then applied to WorldView-2 very-high resolution imagery to determine whether A. dealdata had actually colonized the predicted areas (invasion success. Environmental attributes (topographic, disturbance and canopy-related differing between invaded and non-invaded vegetated areas were then analyzed. The SDM results indicated that most (67% of the study area was climatically suitable for A. dealbata invasion. The onset of invasion was documented to 1905 and satellite mapping highlighted that 12.6% of study area was colonized. However, this species had only colonized 62.5% of the maximum potential range, although was registered within 55.6% of grid cells that were considerable unsuitable. Across these areas, the specific success rate of invasion was mostly below 40%, indicating that A. dealbata invasion was not dominant and effective management may still be possible. Environmental attributes related to topography (slope, canopy (normalized difference vegetation index (ndvi, land surface albedo and disturbance (historical burnt area differed between invaded and non-invaded vegetated area, suggesting that landscape attributes may alter at specific locations with Acacia

  2. Biodiversity hotspots house most undiscovered plant species.

    Science.gov (United States)

    Joppa, Lucas N; Roberts, David L; Myers, Norman; Pimm, Stuart L

    2011-08-09

    For most organisms, the number of described species considerably underestimates how many exist. This is itself a problem and causes secondary complications given present high rates of species extinction. Known numbers of flowering plants form the basis of biodiversity "hotspots"--places where high levels of endemism and habitat loss coincide to produce high extinction rates. How different would conservation priorities be if the catalog were complete? Approximately 15% more species of flowering plant are likely still undiscovered. They are almost certainly rare, and depending on where they live, suffer high risks of extinction from habitat loss and global climate disruption. By using a model that incorporates taxonomic effort over time, regions predicted to contain large numbers of undiscovered species are already conservation priorities. Our results leave global conservation priorities more or less intact, but suggest considerably higher levels of species imperilment than previously acknowledged.

  3. Using GIS to integrate FIA and remotely sensed data to estimate the invasibility of major forest types by non-native invasive plants in the Upper Midwest, USA

    Science.gov (United States)

    Zhaofei Fan; W. Keith Moser; Michael K. Crosby; Weiming Yu

    2012-01-01

    Non-native invasive plants (NNIP) are rapidly spreading into natural ecosystems such as forests in the Upper Midwest. Using the strategic inventory data from the 2005-2006 U.S. Department of Agriculture, Forest Service’s Forest Inventory and Analysis (FIA) program and forest land cover data, we estimated the regional-invasibility patterns of NNIPs for major...

  4. Spatio-temporal segregation and size distribution of fish assemblages as related to non-native species occurrence in the middle rio Doce Valley, MG, Brazil

    Directory of Open Access Journals (Sweden)

    Henrique Corrêa Giacomini

    2011-03-01

    Full Text Available The lakes in the middle rio Doce Valley (MG are suffering impacts due to the introduction of invasive fish species, mainly piscivorous species like red piranha Pygocentrus nattereri and peacock bass Cichla kelberi. Fishes were collected in bimonthly samples conducted at ten lakes along a year. The present study showed that the composition of native fish assemblages is significantly related to the presence and type of non-native species. Fish species distribution among lakes can be explained by differences in species body size: smaller native species are less concentrated in lakes with invasive piscivores, which is in accordance with the hypothesis that they have greater susceptibility to predation by invaders. Another probable cause for this correlation is the proximity of lakes to the drainage system, which could explain both the non-native incidence and the turnover of native species composition. Furthermore, temporal variability in species composition was significantly higher in invaded lakes. This last factor may be linked to seasonal flood pulses, which carry immigrant fishes from streams in the vicinity. The metacommunity framework can bring insights for future studies in such spatially structured systems, and the approach should improve our understanding of processes underlying species composition as well as help direct conservation-focused management plans.Os lagos do Vale do médio rio Doce (MG têm sofrido impactos devido à introdução de espécies invasoras de peixes, principalmente de espécies piscívoras como a piranha Pygocentrus nattereri e o tucunaré Cichla kelberi. Peixes foram coletados em seis amostragens bimestrais durante um ano. O presente trabalho demonstrou que a composição das assembleias de peixes nativos está significativamente relacionada à presença e ao tipo de espécies não nativas. A distribuição de espécies entre os lagos pode ser explicada por diferenças no tamanho corporal: espécies nativas de

  5. Associations of dominant plant species with arbuscular mycorrhizal fungi during vegetation development on coal mine spoil banks

    Energy Technology Data Exchange (ETDEWEB)

    Rydlova, J.; Vosatka, M. [Academy of Science. Pruhonice (Czech Republic). Inst. of Botany

    2001-07-01

    Among plants colonizing mine spoil banks in Northern Bohemia the first colonizers, mainly ruderal annuals from Chenopodiaceae and Brassicaceae were found not to be associated with arbuscular mycorrhizal fungi (AMF). These species cultivated in pots with soil from four sites in different succession stages of the spoil bank did not respond to the presence of native or non-native AMF. All grass species studied (Elytrigia repens, Calamagrostis epigejos and Arrhenatherum elatius) were found moderately colonized in the field. Carduus acanthoides was found to be highly colonized in the field; however, it did not show growth response to AMF in the pot experiment. The AMF native in four sites on the spoil banks showed high infectivity but low effectiveness in association with colonizing plants compared to the non-native isolate G. fistulosum BEG23. In general, dependence on AMF in the cultivation experiment was rather low, regardless of the fact that plants were found to be associated with AMF either in the field or in pots. Occurrence and effectiveness of mycorrhizal associations might relate primarily to the mycotrophic status of each plant species rather than to the age of the spoil bank sites studied.

  6. INVASIVE ALIEN PLANT SPECIES USED FOR THE TREATMENT OF VARIOUS DISEASES IN LIMPOPO PROVINCE, SOUTH AFRICA.

    Science.gov (United States)

    Maema, Lesibana Peter; Potgieter, Martin; Mahlo, Salome Mamokone

    2016-01-01

    Invasive alien plant species (IAPs) are plants that have migrated from one geographical region to non-native region either intentional or unintentional. The general view of IAPs in environment is regarded as destructive to the ecosystem and they pose threat to native vegetation and species. However, some of these IAPS are utilized by local inhabitants as a substitute for scarce indigenous plants. The aim of the study is to conduct ethnobotanical survey on medicinal usage of invasive plant species in Waterberg District, Limpopo Province, South Africa. An ethnobotanical survey on invasive plant species was conducted to distinguish species used for the treatment of various ailments in the Waterberg, District in the area dominated by Bapedi traditional healers. About thirty Bapedi traditional healers (30) were randomly selected via the snowball method. A guided field work by traditional healers and a semi-structured questionnaire was used to gather information from the traditional healers. The questionnaire was designed to gather information on the local name of plants, plant parts used and methods of preparation which is administered by the traditional healers. The study revealed that Schinus molle L., Catharanthus roseus (L.), Datura stramonium L., Opuntia stricta (Haw.) Haw., Opuntia ficus- indica, Sambucus canadensis L., Ricinus communis L., Melia azedarch L., Argemone ochroleuca and Eriobotrya japónica are used for treatment of various diseases such as chest complaint, blood purification, asthma, hypertension and infertility. The most plant parts that were used are 57.6% leaves, followed by 33.3% roots, and whole plant, seeds and bark at 3% each. Noticeably, most of these plants are cultivated (38%), followed by 28% that are common to the study area, 20% abundant, 12% wild, and 3% occasionally. Schinus molle is the most frequently used plant species for the treatment of various ailments in the study area. National Environmental Management Biodiversity Act (NEMBA

  7. Invasive plants found in Louisiana’s forests, 2009 forest inventory and analysis factsheet

    Science.gov (United States)

    Sonja N. Oswalt; Christopher M. Oswalt

    2012-01-01

    Foresters and ecologists have noted the spread of nonnative invasive species onto U.S. forest land for decades. Despite soaring costs related to the management of and removal of invasive plants, and inestimable environmental impacts (e.g., altered soil chemistry, competition with native species, altered light environment; Pimentel and others 2005), nonnative invasive...

  8. Important biological factors for utilizing native plant species

    Science.gov (United States)

    Loren E. Wiesner

    1999-01-01

    Native plant species are valuable resources for revegetation of disturbed ecosystems. The success of these plantings is dependent on the native species selected, quality of seed used, condition of the soil, environmental conditions before and after planting, planting equipment used, time of planting, and other factors. Most native species contain dormant seed. Dormancy...

  9. Germination and early plant development of ten plant species ...

    Science.gov (United States)

    Ten agronomic plant species were exposed to different concentrations of nano titanium dioxide (nTiO2) or nano cerium oxide (nCeO2) (0, 250, 500 and 1000 mg/L) to examine potential effects on germination and early seedling development. We modified a standard test protocol developed for soluble chemicals (OPPTS 850.4200) to determine if such an approach might be useful for screening engineered nanomaterials (ENMs) and whether there were differences in response across a range of commercially important plant species to two common metal oxide ENMs. Eight of 10 species responded to nTiO2, and 5 species responded to nCeO2. Overall, it appeared that early root growth may be a more sensitive indicator of potential effects from ENM exposure than germination. The observed effects did not always relate to the exposure concentration, indicating that mass-based concentration may not fully explain developmental effects of these two ENMs. The results suggest that nTiO2 and nCeO2 have different effects on early plant growth of agronomic species, which may alter the timing of specific developmental events during their life cycle. In addition, standard germination tests, which are commonly used for toxicity screening of new materials, may not detect the subtle but potentially more important changes associated with early growth and development in terrestrial plants. Engineered nanoparticles (ENMs) have been recognized as valuable components of new technologies and are current

  10. Radiocaesium accumulation by different plant species

    International Nuclear Information System (INIS)

    Filiptsova, G.G.

    2000-01-01

    Using the model object influence of mineral nutritions level on radiocaesium accumulation by different plant species has been studied. It was shown the wheat roots accumulation the minimal value on radiocaesium on normal potassium level, the rye roots accumulation maximal level radiocaesium. (authors)

  11. Inventory of the Invasive Alien Plant Species in Indonesia

    OpenAIRE

    TJITROSOEDIRDJO, SRI SUDARMIYATI

    2005-01-01

    An inventory of the alien plant species in Indonesia based on the existing references and herbarium specimens concluded that 1936 alien plant species are found in Indonesia which belong to 187 families. Field studies should be done to get the complete figures of alien plant species in Indonesia. Based on the existing figures of the plant species, the invasive alien plant species can be identified, followed by studies on the assessment of losses, biology, management and their possible utilizat...

  12. A new record of the non-native fish species Butis koilomatodon (Bleeker 1849 (Teleostei: Eleotridae for southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Riguel Feltrin Contente

    2016-05-01

    Full Text Available This work reports the second record of the Indo-Pacific invasive mud sleeper, Butis koilomatodon, for coastal São Paulo in southeastern Brazil, and represents the southernmost record for this species in the southwestern Atlantic Ocean. The risks of a potential invasion mediated by anthropogenic impacts on the area of occurrence are also discussed.

  13. Reservoir to river passage of age-0+ year fishes, indication of a dispersion pathway for a non-native species

    Czech Academy of Sciences Publication Activity Database

    Janáč, Michal; Jurajda, Pavel; Kružíková, L.; Roche, Kevin Francis; Prášek, Václav

    2013-01-01

    Roč. 82, č. 3 (2013), s. 994-1010 ISSN 0022-1112 R&D Projects: GA ČR(CZ) GAP505/11/1768 Institutional support: RVO:68081766 Keywords : Abramis brama * drift * entrainment * invasive species * Proterorhinus semilunaris * Sander lucioperca Subject RIV: EH - Ecology, Behaviour Impact factor: 1.734, year: 2013

  14. Invaders in hot water: a simple decontamination method to prevent the accidental spread of aquatic invasive non-native species.

    Science.gov (United States)

    Anderson, Lucy G; Dunn, Alison M; Rosewarne, Paula J; Stebbing, Paul D

    Watersports equipment can act as a vector for the introduction and spread of invasive non native species (INNS) in freshwater environments. To support advice given to recreational water users under the UK Government's Check Clean Dry biosecurity campaign and ensure its effectiveness at killing a range of aquatic INNS, we conducted a survival experiment on seven INNS which pose a high risk to UK freshwaters. The efficacy of exposure to hot water (45 °C, 15 min) was tested as a method by which waters users could 'clean' their equipment and was compared to drying and a control group (no treatment). Hot water had caused 99 % mortality across all species 1 h after treatment and was more effective than drying at all time points (1 h: χ 2  = 117.24, p  clean equipment. We recommend that it is advocated in future biosecurity awareness campaigns.

  15. A new record of the non-native fish species Butis koilomatodon (Bleeker 1849 (Teleostei: Eleotridae for southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Riguel Feltrin Contente

    2016-05-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2016v29n2p113 This work reports the second record of the Indo-Pacific invasive mud sleeper, Butis koilomatodon, for coastal São Paulo in southeastern Brazil, and represents the southernmost record for this species in the southwestern Atlantic Ocean. The risks of a potential invasion mediated by anthropogenic impacts on the area of occurrence are also discussed.

  16. Evolutionary responses of native plant species to invasive plants : a review

    OpenAIRE

    Oduor, Ayub M. O.

    2013-01-01

    Strong competition from invasive plant species often leads to declines in abundances and may,in certain cases, cause localized extinctions of native plant species. Nevertheless, studies have shown that certain populations of native plant species can co-exist with invasive plant species, suggesting the possibility of adaptive evolutionary responses of those populations to the invasive plants. Empirical inference of evolutionary responses of the native plant species to invasive plants has invol...

  17. Housing is positively associated with invasive exotic plant species richness in New England, USA.

    Science.gov (United States)

    Gavier-Pizarro, Gregorio I; Radeloff, Volker C; Stewart, Susan I; Huebner, Cynthia D; Keuler, Nicholas S

    2010-10-01

    Understanding the factors related to invasive exotic species distributions at broad spatial scales has important theoretical and management implications, because biological invasions are detrimental to many ecosystem functions and processes. Housing development facilitates invasions by disturbing land cover, introducing nonnative landscaping plants, and facilitating dispersal of propagules along roads. To evaluate relationships between housing and the distribution of invasive exotic plants, we asked (1) how strongly is housing associated with the spatial distribution of invasive exotic plants compared to other anthropogenic and environmental factors; (2) what type of housing pattern is related to the richness of invasive exotic plants; and (3) do invasive plants represent ecological traits associated with specific housing patterns? Using two types of regression analysis (best subset analysis and hierarchical partitioning analysis), we found that invasive exotic plant richness was equally or more strongly related to housing variables than to other human (e.g., mean income and roads) and environmental (e.g., topography and forest cover) variables at the county level across New England. Richness of invasive exotic plants was positively related to area of wildland-urban interface (WUI), low-density residential areas, change in number of housing units between 1940 and 2000, mean income, plant productivity (NDVI), and altitudinal range and rainfall; it was negatively related to forest area and connectivity. Plant life history traits were not strongly related to housing patterns. We expect the number of invasive exotic plants to increase as a result of future housing growth and suggest that housing development be considered a primary factor in plans to manage and monitor invasive exotic plant species.

  18. INVENTORY OF THE INVASIVE ALIE N PLANT SPECIES IN INDONESIA

    Directory of Open Access Journals (Sweden)

    SRI S UDARMIYATI T JITROSOEDIRDJO

    2005-01-01

    Full Text Available An inventory of the alien plant species in Indone sia based on the existing references and herbarium specimens concluded that 1936 alien plant species ar e found in Indonesia which belong to 187 families. Field studies should be done to get the complete figur es of alien plant species in Indonesia. Based on the existing figures of the plant species, the invasive alien plant species can be iden tified, followed by studies on the assessment of losses, biology, management and their possible utilizations. Alien plant species are imported to Indonesia for cultivation, collection of the botanical garden, as experimental plants or other curiosities. Aside from plants purposely imported, there are also introduced plant propagules conta-minating imported agricultural products. These alien plant species can be beneficial or have a potential of being invasive. The alien cultivated species consisted of 67% of the total number. More than half of the cultivated plants are ornamental plants. Some of th e species are naturalized or escaped from cultivation and become wild and invasive. Some other natura lized species, adapted well without any problems of invasion. There are 339 species or 17% of the species r ecorded as weeds. The highest record of weeds is found in the family of Poaceae (57 species, follo wed by Asteraceae (53 species and Cyperaceae (35 species. There are 6 families having more than 10 species of weeds: Amaranthaceae, Asteraceae, Cyperaceae, Euphorbiaceae, Poaceae, and Rubiaceae. Three families have more than 100 species: Asteraceae 162 species, Poaceae 120 species, and Papillionaceae 103 species. Five species of aquatic and 20 species of terrestrial plants considered as important alien plant species in Indonesia were identified and some of their distributions noted

  19. Food Plants of 19 butterflies species (Lepidoptera from Loreto, Peru

    Directory of Open Access Journals (Sweden)

    Joel Vásquez Bardales

    2017-04-01

    Full Text Available This work reports the food plants utilized by 19 species of butterflies from Allpahuayo-Mishana Research Center and the Community of San Rafael, Loreto, Peru. We report 23 plant species and one hybrid of angiosperms used by the butterflies. Larval host plants were 21 species and five were adult nectar sources. Two species were both host plant and nectar source: Passiflora coccinea Aubl. and Passiflora edulis Sims. The most frequently used plant families were Solanaceae, Passifloraceae, Fabaceae and Aristolochiaceae.

  20. Density of red squirrels and their use of non-native tree species in the Rogów Arboretum

    Directory of Open Access Journals (Sweden)

    Krauze-Gryz Dagny

    2016-03-01

    Full Text Available The aim of the study was to compare the densities of red squirrel (Sciurus vulgaris in the arboretum and a neighbouring forest and to investigate which tree species the squirrels used. The study was conducted in the area of the Rogów Arboretum (53.76 ha and the so-called Zimna Woda and Wilczy Dół forest complexes (altogether 536 ha, all being part of an Experimental Forest Station in Rogów. The density of squirrels in the arboretum and the neighbouring forest was estimated and compared by means of snow tracks on transect routes. Changes in the abundance of squirrels throughout one year as well as their behaviour were determined on the basis of direct observations along transects running through the arboretum. More than half of the area of the arboretum was searched in order to record feeding signs of squirrels. Additionally, trees with bark stripping were recorded.

  1. Host heterogeneity influences the impact of a non-native disease invasion on populations of a foundation tree species

    Science.gov (United States)

    Jules, Erik S.; Carroll, Allyson L.; Garcia, Andrea M.; Steenbock, Christopher M.; Kauffman, Matthew J.

    2014-01-01

    Invasive pathogens are becoming increasingly important in forested ecosystems, yet they are often difficult to study because of their rapid transmission. The rate and extent of pathogen spread are thought to be partially controlled by variation in host characteristics, such as when host size and location influence susceptibility. Few host-pathogen systems, however, have been used to test this prediction. We used Port Orford cedar (Chamaecyparis lawsoniana), a foundation tree species in riparian areas of California and Oregon (USA), and the invasive oomycete Phytophthora lateralis to assess pathogen impacts and the role of host characteristics on invasion. Across three streams that had been infected for 13–18 years by P. lateralis, we mapped 2241 trees and determined whether they had been infected using dendrochronology. The infection probability of trees was governed by host size (diameter at breast height [DBH]) and geomorphic position (e.g., active channel, stream bank, floodplain, etc.) similarly across streams. For instance, only 23% of trees <20 cm DBH were infected, while 69% of trees ≥20 cm DBH were infected. Presumably, because spores of P. lateralis are transported downstream in water, they are more likely to encounter well-developed root systems of larger trees. Also because of this water-transport of spores, differences in infection probability were found across the geomorphic positions: 59% of cedar in the active channel and the stream bank (combined) were infected, while 23% of trees found on higher geomorphic types were infected. Overall, 32% of cedar had been infected across the three streams. However, 63% of the total cedar basal area had been killed, because the greatest number of trees, and the largest trees, were found in the most susceptible positions. In the active channel and stream bank, 91% of the basal area was infected, while 46% was infected across higher geomorphic positions. The invasion of Port Orford cedar populations by

  2. Clonal growth and plant species abundance.

    Science.gov (United States)

    Herben, Tomáš; Nováková, Zuzana; Klimešová, Jitka

    2014-08-01

    Both regional and local plant abundances are driven by species' dispersal capacities and their abilities to exploit new habitats and persist there. These processes are affected by clonal growth, which is difficult to evaluate and compare across large numbers of species. This study assessed the influence of clonal reproduction on local and regional abundances of a large set of species and compared the predictive power of morphologically defined traits of clonal growth with data on actual clonal growth from a botanical garden. The role of clonal growth was compared with the effects of seed reproduction, habitat requirements and growth, proxied both by LHS (leaf-height-seed) traits and by actual performance in the botanical garden. Morphological parameters of clonal growth, actual clonal reproduction in the garden and LHS traits (leaf-specific area - height - seed mass) were used as predictors of species abundance, both regional (number of species records in the Czech Republic) and local (mean species cover in vegetation records) for 836 perennial herbaceous species. Species differences in habitat requirements were accounted for by classifying the dataset by habitat type and also by using Ellenberg indicator values as covariates. After habitat differences were accounted for, clonal growth parameters explained an important part of variation in species abundance, both at regional and at local levels. At both levels, both greater vegetative growth in cultivation and greater lateral expansion trait values were correlated with higher abundance. Seed reproduction had weaker effects, being positive at the regional level and negative at the local level. Morphologically defined traits are predictive of species abundance, and it is concluded that simultaneous investigation of several such traits can help develop hypotheses on specific processes (e.g. avoidance of self-competition, support of offspring) potentially underlying clonal growth effects on abundance. Garden

  3. Evaluating nurse plants for restoring native woody species to degraded subtropical woodlands.

    Science.gov (United States)

    Yelenik, Stephanie G; DiManno, Nicole; D'Antonio, Carla M

    2015-01-01

    Harsh habitats dominated by invasive species are difficult to restore. Invasive grasses in arid environments slow succession toward more desired composition, yet grass removal exacerbates high light and temperature, making the use of "nurse plants" an appealing strategy. In this study of degraded subtropical woodlands dominated by alien grasses in Hawai'i, we evaluated whether individuals of two native (Dodonaea viscosa, Leptocophylla tameiameia) and one non-native (Morella faya) woody species (1) act as natural nodes of recruitment for native woody species and (2) can be used to enhance survivorship of outplanted native woody species. To address these questions, we quantified the presence and persistence of seedlings naturally recruiting beneath adult nurse shrubs and compared survival and growth of experimentally outplanted seedlings of seven native woody species under the nurse species compared to intact and cleared alien-grass plots. We found that the two native nurse shrubs recruit their own offspring, but do not act as establishment nodes for other species. Morella faya recruited even fewer seedlings than native shrubs. Thus, outplanting will be necessary to increase abundance and diversity of native woody species. Outplant survival was the highest under shrubs compared to away from them with few differences between nurse species. The worst habitat for native seedling survival and growth was within the unmanaged invasive grass matrix. Although the two native nurse species did not differentially affect outplant survival, D. viscosa is the most widespread and easily propagated and is thus more likely to be useful as an initial nurse species. The outplanted species showed variable responses to nurse habitats that we attribute to resource requirements resulting from their typical successional stage and nitrogen fixation capability.

  4. Suitability of California bay laurel and other species as hosts for the non-native redbay ambrosia beetle and granulate ambrosia beetle.

    Science.gov (United States)

    Albert (Bud) Mayfield; Martin MacKenzie; Philip G. Cannon; Steve Oak; Scott Horn; Jaesoon Hwang; Paul E. Kendra

    2013-01-01

    The redbay ambrosia beetle Xyleborus glabratus Eichhoff is a non-native vector of the pathogen that causes laurel wilt, a deadly disease of trees in the family Lauraceae in the southeastern U.S.A.Concern exists that X. glabratus and its fungal symbiont could be transported to the western U....

  5. The Army Priority List of At-Risk Species: 2009-2010 Status Update

    Science.gov (United States)

    2010-09-01

    modification through conifer en- croachment, invasive nonnative plants, roadside maintenance, and grass- land/meadow management activities such as...will be secondarily affecting the species through reduced genetic diversity and limited natural reproduction . Ex- tant populations still occur in the...nonnative plants that compete for light and nutrients; and by the loss of pollinators that negatively affect the reproductive viability of the species

  6. Taxonomic perspective of plant species yielding vegetable oils used ...

    African Journals Online (AJOL)

    A search conducted to determine the plants yielding vegetable oils resulted in 78 plant species with potential use in cosmetics and skin care products. The taxonomic position of these plant species is described with a description of vegetable oils from these plants and their use in cosmetic and skin care products.

  7. Exotic invasive plants

    Science.gov (United States)

    Carolyn Hull Sieg; Barbara G. Phillips; Laura P. Moser

    2003-01-01

    Ecosystems worldwide are threatened by nonnative plant invasions that can cause undesirable, irreversible changes. They can displace native plants and animals, out-cross with native flora, alter nutrient cycling and other ecosystem functions, and even change an ecosystem's flammability (Walker and Smith 1997). After habitat loss, the spread of exotic species is...

  8. Nonnative invasive plants in South Carolina: combining phase-2 with phase-3 vegetation structure and diversity pilot data to enhance our understanding of forest health issues

    Science.gov (United States)

    Sonja N. Oswalt

    2006-01-01

    Studies suggest that the Southeast is an area of primary concern with regards to the spread of alien plant species (Miller 2003, Stapanian and others 1998). Data collected by Stapanian and others in 1998 showed that Japanese honeysuckle (Lonicera japonica) occurred over 2 million acres in the Southeast, invading forests and displacing native species. Among the most...

  9. Plants on the move: plant-soil interactions in poleward shifting plant species

    NARCIS (Netherlands)

    Grunsven, van R.H.A.

    2008-01-01

    As a result of recent global climate change, areas that have previously been climatically unsuitable for species have now become suitable new habitats. Many plant-species are expanding their range polewards, colonizing these newly available areas. If these species are able to expand their range

  10. New pasture plants intensify invasive species risk.

    Science.gov (United States)

    Driscoll, Don A; Catford, Jane A; Barney, Jacob N; Hulme, Philip E; Inderjit; Martin, Tara G; Pauchard, Aníbal; Pyšek, Petr; Richardson, David M; Riley, Sophie; Visser, Vernon

    2014-11-18

    Agricultural intensification is critical to meet global food demand, but intensification threatens native species and degrades ecosystems. Sustainable intensification (SI) is heralded as a new approach for enabling growth in agriculture while minimizing environmental impacts. However, the SI literature has overlooked a major environmental risk. Using data from eight countries on six continents, we show that few governments regulate conventionally bred pasture taxa to limit threats to natural areas, even though most agribusinesses promote taxa with substantial weed risk. New pasture taxa (including species, subspecies, varieties, cultivars, and plant-endophyte combinations) are bred with characteristics typical of invasive species and environmental weeds. By introducing novel genetic and endophyte variation, pasture taxa are imbued with additional capacity for invasion and environmental impact. New strategies to prevent future problems are urgently needed. We highlight opportunities for researchers, agribusiness, and consumers to reduce environmental risks associated with new pasture taxa. We also emphasize four main approaches that governments could consider as they build new policies to limit weed risks, including (i) national lists of taxa that are prohibited based on environmental risk; (ii) a weed risk assessment for all new taxa; (iii) a program to rapidly detect and control new taxa that invade natural areas; and (iv) the polluter-pays principle, so that if a taxon becomes an environmental weed, industry pays for its management. There is mounting pressure to increase livestock production. With foresight and planning, growth in agriculture can be achieved sustainably provided that the scope of SI expands to encompass environmental weed risks.

  11. Impacts of invasive plants on carbon pools depend on both species' traits and local climate.

    Science.gov (United States)

    Martin, Philip A; Newton, Adrian C; Bullock, James M

    2017-04-01

    Invasive plants can alter ecosystem properties, leading to changes in the ecosystem services on which humans depend. However, generalizing about these effects is difficult because invasive plants represent a wide range of life forms, and invaded ecosystems differ in their plant communities and abiotic conditions. We hypothesize that differences in traits between the invader and native species can be used to predict impacts and so aid generalization. We further hypothesize that environmental conditions at invaded sites modify the effect of trait differences and so combine with traits to predict invasion impacts. To test these hypotheses, we used systematic review to compile data on changes in aboveground and soil carbon pools following non-native plant invasion from studies across the World. Maximum potential height (H max ) of each species was drawn from trait databases and other sources. We used meta-regression to assess which of invasive species' H max , differences in this height trait between native and invasive plants, and climatic water deficit, a measure of water stress, were good predictors of changes in carbon pools following invasion. We found that aboveground biomass in invaded ecosystems relative to uninvaded ones increased as the value of H max of invasive relative to native species increased, but that this effect was reduced in more water stressed ecosystems. Changes in soil carbon pools were also positively correlated with the relative H max of invasive species, but were not altered by water stress. This study is one of the first to show quantitatively that the impact of invasive species on an ecosystem may depend on differences in invasive and native species' traits, rather than solely the traits of invasive species. Our study is also the first to show that the influence of trait differences can be altered by climate. Further developing our understanding of the impacts of invasive species using this framework could help researchers to identify not

  12. Meaningful traits for grouping plant species across arid ecosystems.

    Science.gov (United States)

    Bär Lamas, Marlene Ivonne; Carrera, A L; Bertiller, M B

    2016-05-01

    Grouping species may provide some degree of simplification to understand the ecological function of plants on key ecosystem processes. We asked whether groups of plant species based on morpho-chemical traits associated with plant persistence and stress/disturbance resistance reflect dominant plant growth forms in arid ecosystems. We selected twelve sites across an aridity gradient in northern Patagonia. At each site, we identified modal size plants of each dominant species and assessed specific leaf area (SLA), plant height, seed mass, N and soluble phenol concentration in green and senesced leaves at each plant. Plant species were grouped according with plant growth forms (perennial grasses, evergreen shrubs and deciduous shrubs) and plant morphological and/or chemical traits using cluster analysis. We calculated mean values of each plant trait for each species group and plant growth form. Plant growth forms significantly differed among them in most of the morpho-chemical traits. Evergreen shrubs were tall plants with the highest seed mass and soluble phenols in leaves, deciduous shrubs were also tall plants with high SLA and the highest N in leaves, and perennial grasses were short plants with high SLA and low concentration of N and soluble phenols in leaves. Grouping species by the combination of morpho-chemical traits yielded 4 groups in which species from one growth form prevailed. These species groups differed in soluble phenol concentration in senesced leaves and plant height. These traits were highly correlated. We concluded that (1) plant height is a relevant synthetic variable, (2) growth forms adequately summarize ecological strategies of species in arid ecosystems, and (3) the inclusion of plant morphological and chemical traits related to defenses against environmental stresses and herbivory enhanced the potential of species grouping, particularly within shrubby growth forms.

  13. Herbarium specimens show patterns of fruiting phenology in native and invasive plant species across New England.

    Science.gov (United States)

    Gallinat, Amanda S; Russo, Luca; Melaas, Eli K; Willis, Charles G; Primack, Richard B

    2018-01-01

    Patterns of fruiting phenology in temperate ecosystems are poorly understood, despite the ecological importance of fruiting for animal nutrition and seed dispersal. Herbarium specimens represent an under-utilized resource for investigating geographical and climatic factors affecting fruiting times within species, patterns in fruiting times among species, and differences between native and non-native invasive species. We examined over 15,000 herbarium specimens, collected and housed across New England, and found 3159 specimens with ripe fruits, collected from 1849-2013. We examined patterns in fruiting phenology among 37 native and 18 invasive woody plant species common to New England. We compared fruiting dates between native and invasive species, and analyzed how fruiting phenology varies with temperature, space, and time. Spring temperature and year explained a small but significant amount of the variation in fruiting dates. Accounting for the moderate phylogenetic signal in fruiting phenology, invasive species fruited 26 days later on average than native species, with significantly greater standard deviations. Herbarium specimens can be used to detect patterns in fruiting times among species. However, the amount of intraspecific variation in fruiting times explained by temporal, geographic, and climatic predictors is small, due to a combination of low temporal resolution of fruiting specimens and the protracted nature of fruiting. Later fruiting times in invasive species, combined with delays in autumn bird migrations in New England, may increase the likelihood that migratory birds will consume and disperse invasive seeds in New England later into the year. © 2018 Botanical Society of America.

  14. Phytoremediation applications in natural condition and in mesocosm: The uptake of cadmium by Lemna minuta Kunth, a non-native species in Italian watercourses.

    Science.gov (United States)

    Chiudioni, Filippo; Trabace, Teresa; Di Gennaro, Spartaco; Palma, Achille; Manes, Fausto; Mancini, Laura

    2017-04-03

    Metal pollution in water and soil is an environmental and public health issue. Cadmium (Cd) is included in the list of priority hazardous substances in the European Water Framework Directive. Phytoremediation system is a cost-effective, plant-based approach that takes advantage of the ability of plants to concentrate elements and compounds from the environment and to metabolize various molecules in their tissues. We studied the presence and the importance of an invasive species, such as Lemna minuta, in the environment and the effects of Cd pollution on this species. Growth, removal, and tolerance were evaluated for different Cd concentrations and different times of plant exposure. Overall, the results show that L. minuta has a good capacity of growth, metal bioconcentration, and tolerance up to 3 days of exposure at 0.5 and 1.5 mg L -1 of Cd. In particular, L. minuta was able to accumulate Cd up to 3771 mg kg -1 on dry mass basis. We can conclude that L. minuta possesses a great capability of Cd absorption and accumulation, thus supporting a potential use of this species in designing a metal bioremediation system in phytoremediation field.

  15. Alien Plant Species in the Agricultural Habitats of Ukraine: Diversity and Risk Assessment

    Directory of Open Access Journals (Sweden)

    Burda Raisa

    2018-03-01

    Full Text Available This paper is the first critical review of the diversity of the Ukrainian adventive flora, which has spread in agricultural habitats in the 21st century. The author’s annotated checklist contains the data on 740 species, subspecies and hybrids from 362 genera and 79 families of non-native weeds. The floristic comparative method was used, and the information was generalised into some categories of five characteristic features: climamorphotype (life form, time and method of introduction, level of naturalisation, and distribution into 22 classes of three habitat types according to European Nature Information System (EUNIS. Two assessments of the ecological risk of alien plants were first conducted in Ukraine according to the European methods: the risk of overcoming natural migration barriers and the risk of their impact on the environment. The exposed impact of invasive alien plants on ecosystems has a convertible character; the obtained information confirms a high level of phytobiotic contamination of agricultural habitats in Ukraine. It is necessary to implement European and national documents regarding the legislative and regulative policy on invasive alien species as one of the threats to biotic diversity.

  16. VT Biodiversity Project - Plant and Animal Species Atlas

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This database contains town-level totals of documented species records for several plant and animal taxa including vascular plants, trees,...

  17. A new species of the plant bug genus Rubrocuneocoris Schuh (Heteroptera: Miridae: Phylinae) from Hawaii

    Science.gov (United States)

    The new non-native species Rubrocuneocoris calvertae, n. sp. (Heteroptera: Miridae: Phylinae), found on the flowers of the invasive parasol leaf tree, Macaranga tanarius (L.) Müll. Arg., is described from Oahu and Hawaii counties in the Hawaiian Islands. Because the nearest relatives of this new sp...

  18. Phytophthora Species, New Threats to the Plant Health in Korea

    Directory of Open Access Journals (Sweden)

    Ik-Hwa Hyun

    2014-12-01

    Full Text Available Given the lack of a resistant genetic pool in host plants, the introduction of exotic invasive pathogens can result in epidemics that affect a specific ecosystem and economy. Plant quarantine, which is designed to protect endemic plant resources, is a highly invaluable safeguard that should keep biosecurity with increasing international trade and global transportation. A total of 34 species of plant pathogens including Phytophthora infestans were documented as introduced from other countries into Korea from 1900 to 2010. The genus Phytophthora, classified in oomycetes, includes more than 120 species that are mostly recognized worldwide as highly invasive plant pathogens. After 2000, over 50 new species of Phytophthora were identified internationally as plant pathogens occurring in crops and forest trees. In Korea, Phytophthora is also one of the most serious plant pathogens. To date, 22 species (about one-fifth of known species of the genus have been identified and reported as plant pathogens in the country. The likelihood of new exotic Phytophthora species being introduced into Korea continues to increase, thus necessitating intensive plant quarantine inspections. As new potential threats to plant health in Korea, six Phytophthora species, namely, P. alni, P. inundata, P. kernoviae, P. pinifolia, P. quercina, and P. ramorum, are discussed in this review with focus on history, disease, biology, management, and plant quarantine issues.

  19. Invasive Plant Species in the National Parks of Vietnam

    OpenAIRE

    Bernard Dell; Pham Quang Thu; Dang Thanh Tan

    2012-01-01

    The impact of invasive plant species in national parks and forests in Vietnam is undocumented and management plans have yet to be developed. Ten national parks, ranging from uncut to degraded forests located throughout Vietnam, were surveyed for invasive plant species. Transects were set up along roads, trails where local people access park areas, and also tracks through natural forest. Of 134 exotic weeds, 25 were classified as invasive species and the number of invasive species ranged from ...

  20. Evolutionary responses of native plant species to invasive plants: a review.

    Science.gov (United States)

    Oduor, Ayub M O

    2013-12-01

    Strong competition from invasive plant species often leads to declines in abundances and may, in certain cases, cause localized extinctions of native plant species. Nevertheless, studies have shown that certain populations of native plant species can co-exist with invasive plant species,suggesting the possibility of adaptive evolutionary responses of those populations to the invasive plants. Empirical inference of evolutionary responses of the native plant species to invasive plants has involved experiments comparing two conspecific groups of native plants for differences in expression of growth/reproductive traits: populations that have experienced competition from the invasive plant species (i.e. experienced natives) versus populations with no known history of interactions with the invasive plant species (i.e. naıve natives). Here, I employ a meta-analysis to obtain a general pattern of inferred evolutionary responses of native plant species from 53 such studies. In general, the experienced natives had significantly higher growth/reproductive performances than naıve natives, when grown with or without competition from invasive plants.While the current results indicate that certain populations of native plant species could potentially adapt evolutionarily to invasive plant species, the ecological and evolutionary mechanisms that probably underlie such evolutionary responses remain unexplored and should be the focus of future studies.

  1. Using habitat suitability models to target invasive plant species surveys.

    Science.gov (United States)

    Crall, Alycia W; Jarnevich, Catherine S; Panke, Brendon; Young, Nick; Renz, Mark; Morisette, Jeffrey

    2013-01-01

    Managers need new tools for detecting the movement and spread of nonnative, invasive species. Habitat suitability models are a popular tool for mapping the potential distribution of current invaders, but the ability of these models to prioritize monitoring efforts has not been tested in the field. We tested the utility of an iterative sampling design (i.e., models based on field observations used to guide subsequent field data collection to improve the model), hypothesizing that model performance would increase when new data were gathered from targeted sampling using criteria based on the initial model results. We also tested the ability of habitat suitability models to predict the spread of invasive species, hypothesizing that models would accurately predict occurrences in the field, and that the use of targeted sampling would detect more species with less sampling effort than a nontargeted approach. We tested these hypotheses on two species at the state scale (Centaurea stoebe and Pastinaca sativa) in Wisconsin (USA), and one genus at the regional scale (Tamarix) in the western United States. These initial data were merged with environmental data at 30-m2 resolution for Wisconsin and 1-km2 resolution for the western United States to produce our first iteration models. We stratified these initial models to target field sampling and compared our models and success at detecting our species of interest to other surveys being conducted during the same field season (i.e., nontargeted sampling). Although more data did not always improve our models based on correct classification rate (CCR), sensitivity, specificity, kappa, or area under the curve (AUC), our models generated from targeted sampling data always performed better than models generated from nontargeted data. For Wisconsin species, the model described actual locations in the field fairly well (kappa = 0.51, 0.19, P guiding invasive species monitoring, and we support the use of an iterative sampling design for

  2. Effects of invasive alien kahili ginger (Hedychium gardnerianum) on native plant species regeneration in a Hawaiian rainforest

    Science.gov (United States)

    Minden, V.; Jacobi, J.D.; Porembski, S.; Boehmer, H.J.

    2010-01-01

    Questions: Does the invasive alien Hedychium gardnerianum (1) replace native understory species, (2) suppress natural regeneration of native plant species, (3) increase the invasiveness of other non-native plants and (4) are native forests are able to recover after removal of H. gardnerianum. Location: A mature rainforest in Hawai'i Volcanoes National Park on the island of Hawai'i (about 1200 m. a.s.l.; precipitation approximately 2770mm yr-1). Study sites included natural plots without effects of alien plants, ginger plots with a H. gardnerianum-domimted herb layer and cleared plots treated with herbicide to remove alien plants. Methods: Counting mature trees, saplings and seedlings of native and alien plant species. Using nonparametric H-tests to compare impact of H. gardnerianum on the structure of different sites. Results: Results confirmed the hypothesis that H. gardnerianum has negative effects on natural forest dynamics. Lower numbers of native tree seedlings and saplings were found on ginger-dominated plots. Furthermore, H. gardnerianum did not show negative effects on the invasive alien tree species Psidium cattleianum. Conclusions: This study reveals that where dominance of H. gardnerianum persists, regeneration of the forest by native species will be inhibited. Furthermore, these areas might experience invasion by P. cattleianum, resulting in displacement of native canopy species in the future, leading to a change in forest structure and loss of other species dependent on natural rainforest, such as endemic birds. However, if H. gardnerianum is removed the native Hawaiian forest is likely to regenerate and regain its natural structure. ?? 2009 International Association for Vegetation Science.

  3. Impact of nonnative feral pig removal on soil structure and nutrient availability in Hawaiian tropical montane wet forests

    Science.gov (United States)

    Michael S. Long; Creighton M. Litton; Christian P. Giardina; Jonathan Deenik; Rebecca J. Cole; Jed P. Sparks

    2017-01-01

    Conservation and restoration of ecosystems impacted by nonnative ungulates increasingly involves their removal and exclusion. While the influence of nonnative ungulate removal on plant communities is commonly monitored, impacts on underlying ecological processes are seldom quantified. Here we examined how nonnative feral pig (

  4. Exotic plant species attack revegetation plants in post-coal mining areas

    Science.gov (United States)

    Yusuf, Muhammad; Arisoesilaningsih, Endang

    2017-11-01

    This study aimed to explore some invasive exotic plant species that have the potential to disrupt the growth of revegetation plants in post-coal mining areas. This research was conducted in a revegetation area of PT, Amanah Anugerah Adi Mulia (A3M) Kintap site, South Borneo. Direct observation was carried out on some revegetation areas by observing the growth of revegetation plants disturbed by exotic plant species and the spread of exotic plant species. Based on observation, several invasive exotic plant species were identified including Mikania cordata, Centrosema pubescence, Calopogonium mucunoides, Mimosa pudica, Ageratum conyzoides, and Chromolaena odorata. These five plant species grew wild in the revegetation area and showed ability to disrupt the growth of other plants. In some tree species, such as Acacia mangium, Paraserianthes falcataria, M. cordata could inhibit the growth and even kill the trees through covering the tree canopy. So, the trees could not receive optimum sun light for photosynthesis processes. M. cordata was also observed to have the most widespread distribution. Several exotic plant species such as C. mucunoides, M. pudica, and A. conyzoides were observed to have deep root systems compared with plant species used for revegetation. This growth characteristic allowed exotic plant species to win the competition for nutrient absorption with other plant species.

  5. Invasive exotic plant species in Sierra Nevada ecosystems

    Science.gov (United States)

    Carla M. D' Antonio; Eric L. Berlow; Karen L. Haubensak

    2004-01-01

    The Sierra Nevada is a topographically and floristically diverse region of the western United States. While it comprises only a fifth of the total land area of California, half of the native plant species in the state occur within the range. In addition, more than 400 plant species are endemic to the Sierra Nevada and many of these are listed as threatened or have...

  6. Small nonnative fishes as predators of larval razorback suckers

    Science.gov (United States)

    Carpenter, J.; Mueller, G.A.

    2008-01-01

    The razorback sucker (Xyrauchen texanus), an endangered big-river fish of the Colorado River basin, has demonstrated no sustainable recruitment in 4 decades, despite presence of spawning adults and larvae. Lack of adequate recruitment has been attributed to several factors, including predation by nonnative fishes. Substantial funding and effort has been expended on mechanically removing nonnative game fishes, typically targeting large predators. As a result, abundance of larger predators has declined, but the abundance of small nonnative fishes has increased in some areas. We conducted laboratory experiments to determine if small nonnative fishes would consume larval razorback suckers. We tested adults of three small species (threadfin shad, Dorosoma petenense; red shiner, Cyprinella lutrensis; fathead minnow, Pimephales promelas) and juveniles of six larger species (common carp, Cyprinus carpio; yellow bullhead, Ameiurus natalis; channel catfish, Ictalurus punctatus; rainbow trout, Oncorhynchus mykiss; green sunfish, Lepomis cyanellus; bluegill, L. macrochirus). These nonnative fishes span a broad ecological range and are abundant within the historical range of the razorback sucker. All nine species fed on larval razorback suckers (total length, 9-16 mm). Our results suggest that predation by small nonnative fishes could be responsible for limiting recovery of this endangered species.

  7. Co-occurring nonnative woody shrubs have additive and non-additive soil legacies

    DEFF Research Database (Denmark)

    Kuebbing, Sara E.; Patterson, Courtney M.; Classen, Aimee Taylor

    2016-01-01

    shrubs, Lonicera maackii and Ligustrum sinense, in deciduous forests of the southeastern United States. We measured the performance of each nonnative shrub, a native herbaceous community, and a nonnative woody vine in soils conditioned by each shrub singly or together in polyculture. Soils conditioned...... by both nonnative shrubs had non-additive impacts on native and nonnative performance. Root mass of the native herbaceous community was 1.5 times lower and the root mass of the nonnative L. sinense was 1.8 times higher in soils conditioned by both L. maackii and L. sinense than expected based upon growth...... in soils conditioned by either shrub singly. This result indicates that when these two nonnative shrubs co-occur, their influence on soils disproportionally favors persistence of the nonnative L. sinense relative to this native herbaceous community, and could provide an explanation of why native species...

  8. Loss of native herbaceous species due to woody plant encroachment facilitates the establishment of an invasive grass.

    Science.gov (United States)

    Alofs, Karen M; Fowler, Norma L

    2013-03-01

    Although negative relationships between diversity (frequently measured as species richness) and invasibility at neighborhood or community scales have often been reported, realistic natural diversity gradients have rarely been studied at this scale. We recreated a naturally occurring gradient in species richness to test the effects of species richness on community invasibility. In central Texas savannas, as the proportion of woody plants increases (a process known as woody plant encroachment), herbaceous habitat is both lost and fragmented, and native herbaceous species richness declines. We examined the effects of these species losses on invasibility in situ by removing species that occur less frequently in herbaceous patches as woody plant encroachment advances. This realistic species removal was accompanied by a parallel and equivalent removal of biomass with no changes in species richness. Over two springs, the nonnative bunchgrass Bothriochloa ischaemum germinated significantly more often in the biomass-removal treatment than in unmanipulated control plots, suggesting an effect of native plant density independent of diversity. Additionally, significantly more germination occurred in the species-removal treatment than in the biomass-removal treatment. Changes in species richness had a stronger effect on B. ischaemum germination than changes in plant density, demonstrating that niche-related processes contributed more to biotic resistance in this system than did species-neutral competitive interactions. Similar treatment effects were found on transplant growth. Thus we show that woody plant encroachment indirectly facilitates the establishment of an invasive grass by reducing native diversity. Although we found a negative relationship between species richness and invasibility at the scale of plots with similar composition and environmental conditions, we found a positive relationship between species richness and invasibility at larger scales. This apparent

  9. Ozone injury to some Japanese woody plant species in summer

    Energy Technology Data Exchange (ETDEWEB)

    Kadota, M; Ohta, K

    1972-01-01

    Ozone is an important constituent of photochemical oxidant smog. This paper reveals the semiquantitative responses of various Japanese woody plant species to ozone (0.25 ppm). Plant species examined in this investigation include four coniferous trees, eleven evergreen broad-leaf trees, and twenty-one deciduous broad-leaf trees or shrubs. Generally, plants having thin leaves were susceptible. The plant species with higher activity of photosynthesis appeared to be more susceptible. As a whole, evergreen broad-leaf trees could be said to be more resistant to ozone than deciduous broad-leaf trees.

  10. Support Vector Machine Based Tool for Plant Species Taxonomic Classification

    OpenAIRE

    Manimekalai .K; Vijaya.MS

    2014-01-01

    Plant species are living things and are generally categorized in terms of Domain, Kingdom, Phylum, Class, Order, Family, Genus and name of Species in a hierarchical fashion. This paper formulates the taxonomic leaf categorization problem as the hierarchical classification task and provides a suitable solution using a supervised learning technique namely support vector machine. Features are extracted from scanned images of plant leaves and trained using SVM. Only class, order, family of plants...

  11. Life styles of Colletotrichum species and implications for plant biosecurity

    NARCIS (Netherlands)

    Silva, Dilani D. De; Crous, Pedro W.; Ades, Peter Kevin; Hyde, Kevin D.; Taylor, Paul W. J.

    Colletotrichum is a genus of major plant pathogens causing anthracnose diseases in many plant crops worldwide. The genus comprises a highly diverse group of pathogens that infect a wide range of plant hosts. The life styles of Colletotrichum species can be broadly categorised as necrotrophic,

  12. Coexistence induced by pollen limitation in flowering-plant species.

    OpenAIRE

    Ishii, R; Higashi, M

    2001-01-01

    We report a novel mechanism for species coexistence that does not invoke a trade-off relationship in the case of outbreeding flowering plants. Competition for pollination services may lead to interspecific segregation of the timing of flowering among plants. This, in turn, sets limits on the pollination services, which restrain the population growth of a competitively superior species, thereby allowing an inferior species to sustain its population in the habitat. This explains the often-obser...

  13. [Species diversity of ex-situ cultivated Chinese medicinal plants].

    Science.gov (United States)

    Que, Ling; Chi, Xiu-Lian; Zang, Chun-Xin; Zhang, Yu; Chen, Min; Yang, Guang; Jin, An-Qi

    2018-03-01

    Ex-situ conservation is an important means to protect biological genetic resources. Resource protection has received more and more attention with the continuous improvement of the comprehensive utilization of traditional Chinese medicine resources. In this paper, the research and compilation of the species list of ex-situ cultivated medicinal plants in 12 Chinese Academy of Sciences botanic gardens and 19 specialized medicinal botanic gardens in China were carried out. Based on the Species 2000(2017) and other classification databases, species diversity of medicinal plants ex-situ cultivated in these botanical gardens were analyzed. The study found that there were 16 351 higher plant species in our country, belonging to 276 families and 1 936 genera. Of these, 6 949 specieswere medicinal plants, accounting for 50.4% of the total medicinal plants. There were 1 280 medicinal plants were in threatened status, accounting for 19.6% of all threatened species in the Chinese Biodiversity Red List, with ex-situ cultivated proportion of 59.5%. And 3 988 medicinal plants were Chinese endemic species, accounting for 22.5% of all Chinese endemic species, with ex-situ cultivated proportion of 53.3%. This article has reference significance for the management and protection of medicinal plant resources. Copyright© by the Chinese Pharmaceutical Association.

  14. Distribution patterns of rare earth elements in various plant species

    Energy Technology Data Exchange (ETDEWEB)

    Wyttenbach, A.; Tobler, L.; Furrer, V. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    The elements La, Ce, Nd, Sm, Eu, Gd, Tb, Yb and Lu have been determined in 6 different plant species by neutron activation analysis. When the concentrations of each species were normalized to Norway spruce, smooth curves were obtained which revealed systematic inter-species differences. (author) 3 figs., 4 refs.

  15. Distribution patterns of rare earth elements in various plant species

    International Nuclear Information System (INIS)

    Wyttenbach, A.; Tobler, L.; Furrer, V.

    1997-01-01

    The elements La, Ce, Nd, Sm, Eu, Gd, Tb, Yb and Lu have been determined in 6 different plant species by neutron activation analysis. When the concentrations of each species were normalized to Norway spruce, smooth curves were obtained which revealed systematic inter-species differences. (author) 3 figs., 4 refs

  16. Clonal growth and plant species abundance

    Czech Academy of Sciences Publication Activity Database

    Herben, Tomáš; Nováková, Z.; Klimešová, Jitka

    2014-01-01

    Roč. 114, č. 2 (2014), s. 377-388 ISSN 0305-7364 R&D Projects: GA ČR GA526/09/0963 Institutional support: RVO:67985939 Keywords : clonal plants * frequency * plant communities of Central Europe Subject RIV: EF - Botanics Impact factor: 3.654, year: 2014

  17. Exotic plant species receive adequate pollinator service despite variable integration into plant-pollinator networks.

    Science.gov (United States)

    Thompson, Amibeth H; Knight, Tiffany M

    2018-05-01

    Both exotic and native plant species rely on insect pollinators for reproductive success, and yet few studies have evaluated whether and how exotic plant species receive services from native pollinators for successful reproduction in their introduced range. Plant species are expected to successfully reproduce in their exotic range if they have low reliance on animal pollinators or if they successfully integrate themselves into resident plant-pollinator networks. Here, we quantify the breeding system, network integration, and pollen limitation for ten focal exotic plant species in North America. Most exotic plant species relied on animal pollinators for reproduction, and these species varied in their network integration. However, plant reproduction was limited by pollen receipt for only one plant species. Our results demonstrate that even poorly integrated exotic plant species can still have high pollination service and high reproductive success. The comprehensive framework considered here provides a method to consider the contribution of plant breeding systems and the pollinator community to pollen limitation, and can be applied to future studies to provide a more synthetic understanding of the factors that determine reproductive success of exotic plant species.

  18. 78 FR 46889 - Endangered and Threatened Wildlife and Plants; 12-Month Finding and Candidate Removal for...

    Science.gov (United States)

    2013-08-02

    ... Removal for Potentilla basaltica; Proposed Threatened Species Status for Ivesia webberi AGENCY: Fish and..., invasive plant species--have been substantially reduced since 2002. The BLM implemented several measures... respond to nonnative, invasive plant species using chemical control and other treatment methods (Service...

  19. Phytotoxic studies of medicinal plant species of Pakistan

    International Nuclear Information System (INIS)

    Gilani, S.A.; Adnan, M.; Kikuchi, A.; Fujii, Y.; Shinwari, Z.K.; Kazuo, N.; Watanabe, K.N.

    2010-01-01

    Allelopathic screening of 81 medicinal plant species, collected from North West Frontier Province (NWFP) Pakistan, was carried out to identify significantly higher allelopathic species for future phyto chemical analyses. For this purpose, sandwich method was used to test allelopathic potentials of leaf leachates of these plant species against lettuce seeds (Lactuca sativa L.). Two different concentrations of 10 mg and 50 mg of leaf leachates were used in the study. The radicle and hypocotyl growths were measured and compared with control treatments. It was observed that an endemic species Seriphidium kurramense, Andrachne cordifolia and Rhazya stricta were the stronger phyto toxic plants as compared to the other test species. Based on the current screening, three potential medicinal plants are recommended for future bioassay guided isolation of allelochemicals and for genetic diversity studies. It would also be interesting to see correlation between genetic markers and isolated allelochemicals. (author)

  20. Site and plant species are important determinants of the Methylobacterium community composition in the plant phyllosphere.

    Science.gov (United States)

    Knief, Claudia; Ramette, Alban; Frances, Lisa; Alonso-Blanco, Carlos; Vorholt, Julia A

    2010-06-01

    The plant phyllosphere constitutes a habitat for numerous microorganisms; among them are members of the genus Methylobacterium. Owing to the ubiquitous occurrence of methylobacteria on plant leaves, they represent a suitable target for studying plant colonization patterns. The influence of the factor site, host plant species, time and the presence of other phyllosphere bacteria on Methylobacterium community composition and population size were evaluated in this study. Leaf samples were collected from Arabidopsis thaliana or Medicago truncatula plants and from the surrounding plant species at several sites. The abundance of cultivable Methylobacterium clearly correlated with the abundance of other phyllosphere bacteria, suggesting that methylobacteria constitute a considerable and rather stable fraction of the phyllosphere microbiota under varying environmental conditions. Automated ribosomal intergenic spacer analysis (ARISA) was applied to characterize the Methylobacterium community composition and showed the presence of similar communities on A. thaliana plants at most sites in 2 consecutive years of sampling. A substantial part of the observed variation in the community composition was explained by site and plant species, especially in the case of the plants collected at the Arabidopsis sites (50%). The dominating ARISA peaks that were detected on A. thaliana plants were found on other plant species grown at the same site, whereas some different peaks were detected on A. thaliana plants from other sites. This indicates that site-specific factors had a stronger impact on the Methylobacterium community composition than did plant-specific factors and that the Methylobacterium-plant association is not highly host plant species specific.

  1. Plant species richness enhances nitrogen retention in green roof plots.

    Science.gov (United States)

    Johnson, Catherine; Schweinhart, Shelbye; Buffam, Ishi

    2016-10-01

    Vegetated (green) roofs have become common in many cities and are projected to continue to increase in coverage, but little is known about the ecological properties of these engineered ecosystems. In this study, we tested the biodiversity-ecosystem function hypothesis using commercially available green roof trays as replicated plots with varying levels of plant species richness (0, 1, 3, or 6 common green roof species per plot, using plants with different functional characteristics). We estimated accumulated plant biomass near the peak of the first full growing season (July 2013) and measured runoff volume after nearly every rain event from September 2012 to September 2013 (33 events) and runoff fluxes of inorganic nutrients ammonium, nitrate, and phosphate from a subset of 10 events. We found that (1) total plant biomass increased with increasing species richness, (2) green roof plots were effective at reducing storm runoff, with vegetation increasing water retention more than soil-like substrate alone, but there was no significant effect of plant species identity or richness on runoff volume, (3) green roof substrate was a significant source of phosphate, regardless of presence/absence of plants, and (4) dissolved inorganic nitrogen (DIN = nitrate + ammonium) runoff fluxes were different among plant species and decreased significantly with increasing plant species richness. The variation in N retention was positively related to variation in plant biomass. Notably, the increased biomass and N retention with species richness in this engineered ecosystem are similar to patterns observed in published studies from grasslands and other well-studied ecosystems. We suggest that more diverse plantings on vegetated roofs may enhance the retention capacity for reactive nitrogen. This is of importance for the sustained health of vegetated roof ecosystems, which over time often experience nitrogen limitation, and is also relevant for water quality in receiving waters

  2. Connecting infrared spectra with plant traits to identify species

    Science.gov (United States)

    Buitrago, Maria F.; Skidmore, Andrew K.; Groen, Thomas A.; Hecker, Christoph A.

    2018-05-01

    Plant traits are used to define species, but also to evaluate the health status of forests, plantations and crops. Conventional methods of measuring plant traits (e.g. wet chemistry), although accurate, are inefficient and costly when applied over large areas or with intensive sampling. Spectroscopic methods, as used in the food industry and mineralogy, are nowadays applied to identify plant traits, however, most studies analysed visible to near infrared, while infrared spectra of longer wavelengths have been little used for identifying the spectral differences between plant species. This study measured the infrared spectra (1.4-16.0 μm) on individual, fresh leaves of 19 species (from herbaceous to woody species), as well as 14 leaf traits for each leaf. The results describe at which wavelengths in the infrared the leaves' spectra can differentiate most effectively between these plant species. A Quadratic Discrimination Analysis (QDA) shows that using five bands in the SWIR or the LWIR is enough to accurately differentiate these species (Kappa: 0.93, 0.94 respectively), while the MWIR has a lower classification accuracy (Kappa: 0.84). This study also shows that in the infrared spectra of fresh leaves, the identified species-specific features are correlated with leaf traits as well as changes in their values. Spectral features in the SWIR (1.66, 1.89 and 2.00 μm) are common to all species and match the main features of pure cellulose and lignin spectra. The depth of these features varies with changes of cellulose and leaf water content and can be used to differentiate species in this region. In the MWIR and LWIR, the absorption spectra of leaves are formed by key species-specific traits including lignin, cellulose, water, nitrogen and leaf thickness. The connection found in this study between leaf traits, features and spectral signatures are novel tools to assist when identifying plant species by spectroscopy and remote sensing.

  3. Larvicidal activity of six Nigerian plant species against Anopheles ...

    African Journals Online (AJOL)

    This study evaluated the larvicidal activity of extracts from six Nigerian plant species (Zanthoxylum zanthoxyloides, Piper guineense, Nicotianat abacum, Erythrophleum suaveoleus, Jatropha curcas and Petiveria alliacea) against laboratory-bred Anopheles gambiae and Aedes aegypti larvae. Zanthoxylum zanthoxyloides ...

  4. Variation of interception loss with different plant species at the ...

    African Journals Online (AJOL)

    USER

    Department of Water Resources Management and Agrometeorology, University of ... Interception studies of six plants groups were carried out at the campus of University of Agriculture, ... species, leaf area, seasonal characteristics and leaf.

  5. Human population, grasshopper and plant species richness in European countries

    Science.gov (United States)

    Steck, Claude E.; Pautasso, Marco

    2008-11-01

    Surprisingly, several studies over large scales have reported a positive spatial correlation of people and biodiversity. This pattern has important implications for conservation and has been documented for well studied taxa such as plants, amphibians, reptiles, birds and mammals. However, it is unknown whether the pattern applies also to invertebrates other than butterflies and more work is needed to establish whether the species-people relationship is explained by both variables correlating with other environmental factors. We studied whether grasshopper species richness (Orthoptera, suborder Caelifera) is related to human population size in European countries. As expected, the number of Caelifera species increases significantly with increasing human population size. But this is not the case when controlling for country area, latitude and number of plant species. Variations in Caelifera species richness are primarily associated with variations in plant species richness. Caelifera species richness also increases with decreasing mean annual precipitation, Gross Domestic Product per capita (used as an indicator for economic development) and net fertility rate of the human population. Our analysis confirms the hypothesis that the broad-scale human population-biodiversity correlations can be explained by concurrent variations in factors other than human population size such as plant species richness, environmental productivity, or habitat heterogeneity. Nonetheless, more populated countries in Europe still have more Caelifera species than less populated countries and this poses a particular challenge for conservation.

  6. Widespread plant species: natives vs. aliens in our changing world

    Science.gov (United States)

    Stohlgren, Thomas J.; Pyšek, Petr; Kartesz, John; Nishino, Misako; Pauchard, Aníbal; Winter, Marten; Pino, Joan; Richardson, David M.; Wilson, John R.U.; Murray, Brad R.; Phillips, Megan L.; Ming-yang, Li; Celesti-Grapow, Laura; Font, Xavier

    2011-01-01

    Estimates of the level of invasion for a region are traditionally based on relative numbers of native and alien species. However, alien species differ dramatically in the size of their invasive ranges. Here we present the first study to quantify the level of invasion for several regions of the world in terms of the most widely distributed plant species (natives vs. aliens). Aliens accounted for 51.3% of the 120 most widely distributed plant species in North America, 43.3% in New South Wales (Australia), 34.2% in Chile, 29.7% in Argentina, and 22.5% in the Republic of South Africa. However, Europe had only 1% of alien species among the most widespread species of the flora. Across regions, alien species relative to native species were either as well-distributed (10 comparisons) or more widely distributed (5 comparisons). These striking patterns highlight the profound contribution that widespread invasive alien plants make to floristic dominance patterns across different regions. Many of the most widespread species are alien plants, and, in particular, Europe and Asia appear as major contributors to the homogenization of the floras in the Americas. We recommend that spatial extent of invasion should be explicitly incorporated in assessments of invasibility, globalization, and risk assessments.

  7. Widespread plant species: Natives versus aliens in our changing world

    Science.gov (United States)

    Stohlgren, T.J.; Pysek, P.; Kartesz, J.; Nishino, M.; Pauchard, A.; Winter, M.; Pino, J.; Richardson, D.M.; Wilson, J.R.U.; Murray, B.R.; Phillips, M.L.; Ming-yang, L.; Celesti-Grapow, L.; Font, X.

    2011-01-01

    Estimates of the level of invasion for a region are traditionally based on relative numbers of native and alien species. However, alien species differ dramatically in the size of their invasive ranges. Here we present the first study to quantify the level of invasion for several regions of the world in terms of the most widely distributed plant species (natives vs. aliens). Aliens accounted for 51.3% of the 120 most widely distributed plant species in North America, 43.3% in New South Wales (Australia), 34.2% in Chile, 29.7% in Argentina, and 22.5% in the Republic of South Africa. However, Europe had only 1% of alien species among the most widespread species of the flora. Across regions, alien species relative to native species were either as well-distributed (10 comparisons) or more widely distributed (5 comparisons). These striking patterns highlight the profound contribution that widespread invasive alien plants make to floristic dominance patterns across different regions. Many of the most widespread species are alien plants, and, in particular, Europe and Asia appear as major contributors to the homogenization of the floras in the Americas. We recommend that spatial extent of invasion should be explicitly incorporated in assessments of invasibility, globalization, and risk assessments. ?? 2011 Springer Science+Business Media B.V.

  8. Thermal Hyperspectral Remote Sensing for Plant Species and Stress Detection

    Science.gov (United States)

    Schlerf, M.; Rock, G.; Ullah, S.; Gerhards, M.; Udelhoven, T.; Skidmore, A. K.

    2014-12-01

    Thermal infrared (TIR) spectroscopy offers a novel opportunity for measuring emissivity spectra of natural surfaces. Emissivity spectra are not directly measured, they first have to be retrieved from the raw measurements. Once retrieved, the spectra can be used, for example, to discriminate plant species or to detect plant stress. Knowledge of plant species distribution is essential for the sustainable management of ecosystems. Remote sensing of plant species has so far mostly been limited to data in the visible and near-infrared where, however, different species often reveal similar reflectance curves. Da Luz and Crowley showed in a recent paper that in the TIR plants indeed have distinct spectral features. Also with a certain species, subtle changes of emissivity in certain wavebands may occur, when biochemical compounds change due to osmotic adjustment induced by water stress. Here we show, that i) emissive imaging spectroscopy allows for reliable and accurate retrieval of plant emissivity spectra, ii) emissivity spectra are well suited to discriminate plant species, iii) a reduction in stomatal conductance (caused by stress) changes the thermal infrared signal. For 13 plant species in the laboratory and for 8 plant species in a field setup emissivity spectra were retrieved. A comparison shows, that for most species the shapes of the emissivity curves agree quite well, but that clear offsets between the two types of spectra exist. Discrimination analysis revealed that based on the lab spectra, 13 species could be distinguished with an average overall classification accuracy of 92% using the 6 best spectral bands. For the field spectra (8 species), a similar high OAA of 89% was achieved. Species discrimination is likely to be possible due to variations in the composition of the superficial epidermal layer of plant leaves and in internal chemical concentrations producing unique emissivity features. However, to date, which spectral feature is responsible for which

  9. Genetic diversity within a dominant plant outweighs plant species diversity in structuring an arthropod community.

    Science.gov (United States)

    Crawford, Kerri M; Rudgers, Jennifer A

    2013-05-01

    Plant biodiversity is being lost at a rapid rate. This has spurred much interest in elucidating the consequences of this loss for higher trophic levels. Experimental tests have shown that both plant species diversity and genetic diversity within a plant species can influence arthropod community structure. However, the majority of these studies have been conducted in separate systems, so their relative importance is currently unresolved. Furthermore, potential interactions between the two levels of diversity, which likely occur in natural systems, have not been investigated. To clarify these issues, we conducted three experiments in a freshwater sand dune ecosystem. We (1) independently manipulated plant species diversity, (2) independently manipulated genetic diversity within the dominant plant species, Ammophila breviligulata, and (3) jointly manipulated genetic diversity within the dominant plant and species diversity. We found that genetic diversity within the dominant plant species, Ammophila breviligulata, more strongly influenced arthropod communities than plant species diversity, but this effect was dependent on the presence of other species. In species mixtures, A. breviligulata genetic diversity altered overall arthropod community composition, and arthropod richness and abundance peaked at the highest level of genetic diversity. Positive nonadditive effects of diversity were detected, suggesting that arthropods respond to emergent properties of diverse plant communities. However, in the independent manipulations where A. breviligulata was alone, effects of genetic diversity were weaker, with only arthropod richness responding. In contrast, plant species diversity only influenced arthropods when A. breviligulata was absent, and then only influenced herbivore abundance. In addition to showing that genetic diversity within a dominant plant species can have large effects on arthropod community composition, these results suggest that understanding how species

  10. Short-Term Response of Native Flora to the Removal of Non-Native Shrubs in Mixed-Hardwood Forests of Indiana, USA

    Directory of Open Access Journals (Sweden)

    Joshua M. Shields

    2015-05-01

    Full Text Available While negative impacts of invasive species on native communities are well documented, less is known about how these communities respond to the removal of established populations of invasive species. With regard to invasive shrubs, studies examining native community response to removal at scales greater than experimental plots are lacking. We examined short-term effects of removing Lonicera maackii (Amur honeysuckle and other non-native shrubs on native plant taxa in six mixed-hardwood forests. Each study site contained two 0.64 ha sample areas—an area where all non-native shrubs were removed and a reference area where no treatment was implemented. We sampled vegetation in the spring and summer before and after non-native shrubs were removed. Cover and diversity of native species, and densities of native woody seedlings, increased after shrub removal. However, we also observed significant increases in L. maackii seedling densities and Alliaria petiolata (garlic mustard cover in removal areas. Changes in reference areas were less pronounced and mostly non-significant. Our results suggest that removing non-native shrubs allows short-term recovery of native communities across a range of invasion intensities. However, successful restoration will likely depend on renewed competition with invasive species that re-colonize treatment areas, the influence of herbivores, and subsequent control efforts.

  11. Plant invasion and speciation along elevational gradients on the oceanic island La Palma, Canary Islands

    DEFF Research Database (Denmark)

    Steinbauer, Manuel; Irl, Severin David Howard; González-Mancebo, Juana Maria

    2017-01-01

    and anthropogenic filters, thus controlling the dispersal and establishment of species. Here, we investigate speciation and invasion processes along elevational gradients. Methods: We assess the vascular plant species richness as well as the number and percentage of endemic species and non-native species...

  12. Plant species responses to oil degradation and toxicity reduction in ...

    African Journals Online (AJOL)

    Vegetated plots were established by planting different plant species – legumes and vegetable (Abelmoschus, esculentus, Telfaria occidentalis and Vigna unguiculata) and applied with sawdust and chromolaena leaves at different intensities of oil pollution. Toxicity of the soil was evaluated using germination percentage, ...

  13. Eco-taxonomic distribution of plant species around motor mechanic ...

    African Journals Online (AJOL)

    A survey of plant species and their families present in auto mechanic workshops in Benin City and Asaba was carried out. The frequency of occurrence of plants in the sites visited was used to determine prevalence. Peperomia pellucida occurred most in all the sites visited with a 55% frequency. The high rate of occurrence ...

  14. Plant species richness regulates soil respiration through changes in productivity.

    NARCIS (Netherlands)

    Tavares Correa Dias, A.; van Ruijven, J.; Berendse, F.

    2010-01-01

    Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of

  15. Plant species richness regulates soil respiration through changes in productivity

    NARCIS (Netherlands)

    Dias, A.A.; Ruijven, van J.; Berendse, F.

    2010-01-01

    Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of

  16. Species composition, plant cover and diversity of recently reforested ...

    African Journals Online (AJOL)

    SERVER

    2007-12-17

    Dec 17, 2007 ... Deforestation, over-cultivation and rural growth have severely ... over-cultivation, plant populations changed, and biolo- ... Restoring community structure (e.g. species composi-tion ... plant diversity at all spatial scales are the criteria that should ..... taxonomic groups in recovering and restored forests.

  17. ecotaxonomic baseline evaluation of the plant species in a ...

    African Journals Online (AJOL)

    Admin

    plant species of medicinal and other economic values. The investigation was ... A total of 41 and 24 representative ... INTRODUCTION. Baseline .... at 100m interval, involving a total of 15 sampling locations .... explained by factors such as climate, productivity and ... encouraging the: Maintenance of traditional tree species.

  18. Plant species classification using deep convolutional neural network

    DEFF Research Database (Denmark)

    Dyrmann, Mads; Karstoft, Henrik; Midtiby, Henrik Skov

    2016-01-01

    Information on which weed species are present within agricultural fields is important for site specific weed management. This paper presents a method that is capable of recognising plant species in colour images by using a convolutional neural network. The network is built from scratch trained an...

  19. Rare vascular plant species at risk : recovery by seeding?

    NARCIS (Netherlands)

    Pegtel, Dick M.

    . Rare vascular plant species are endangered worldwide. Population losses are most commonly caused by human-related factors. Conservation management seeks to halt this adverse trend and if possible, to enhance long-lasting self-sustainable populations. In general, rare species are poorly recruited

  20. When Are Native Species Inappropriate for Conservation Plantings

    Science.gov (United States)

    Conservation agencies and organizations are generally reluctant to encourage the use of invasive plant species in conservation programs. Harsh lessons learned in the past have resulted in tougher screening protocols for non-indigenous species introductions and removal of many no...

  1. Characterizing the Status (Disturbed, Hybrid or Novel) of Swamp Forest Fragments in a Caribbean Ramsar Wetland: The Impact of Anthropogenic Degradation and Invasive Plant Species.

    Science.gov (United States)

    Prospere, Kurt; McLaren, Kurt P; Wilson, Byron

    2016-10-01

    The last remaining Amazonian-type swamp forest fragments in Black River Lower Morass, Jamaica, have been subjected to a myriad of anthropogenic disturbances, compounded by the establishment and spread of several invasive plant species. We established 44 permanent sample plots (covering 3.92 ha) across 10 of these swamp forest fragments and sampled all non-woody plants and all trees ≥2 cm DBH found in the plots. These data were used to (1) identify thresholds of hybridity and novelty, (2) derive several diversity and structural descriptors used to characterize the swamp forest fragments and (3) identify possible indicators of anthropogenic degradation. These were incorporated into a framework and used to determine the status of the swamp forest fragments so that appropriate management and conservation measures can be implemented. We recorded 43 woody plant species (9 endemic, 28 native and 4 non-native) and 21 non-tree species. The composition and structure of all the patches differed significantly due to the impact of the herbaceous invasive plant Alpinia allughas, the presence and diversity of other non-native plants, and differing intensities of anthropogenic disturbance (e.g., burning, cutting and harvesting of non-timber forest products). We ranked forest patches along a continuum representing deviations from a historical proxy (least disturbed) swamp forest to those with dramatically altered structural and floristic attributes (=novel swamp forests). Only one fragment overrun with A. allughas was classified as novel. If effective conservation and management does not come to the BRLM, the remaining swamp forest fragments appear doomed to further degradation and will soon disappear altogether.

  2. Resolving whether botanic gardens are on the road to conservation or a pathway for plant invasions.

    Science.gov (United States)

    Hulme, Philip E

    2015-06-01

    A global conservation goal is to understand the pathways through which invasive species are introduced into new regions. Botanic gardens are a pathway for the introduction of invasive non-native plants, but a quantitative assessment of the risks they pose has not been performed. I analyzed data on the living collections of over 3000 botanic gardens worldwide to quantify the temporal trend in the representation of non-native species; the relative composition of threatened, ornamental, or invasive non-native plant species; and the frequency with which botanic gardens implement procedures to address invasive species. While almost all of the world's worst invasive non-native plants occurred in one or more living collections (99%), less than one-quarter of red-listed threatened species were cultivated (23%). Even when cultivated, individual threatened species occurred in few living collections (7.3), while non-native species were on average grown in 6 times as many botanic gardens (44.3). As a result, a botanic garden could, on average, cultivate four times as many invasive non-native species (20) as red-listed threatened species (5). Although the risk posed by a single living collection is small, the probability of invasion increases with the number of botanic gardens within a region. Thus, while both the size of living collections and the proportion of non-native species cultivated have declined during the 20th century, this reduction in risk is offset by the 10-fold increase in the number of botanic gardens established worldwide. Unfortunately, botanic gardens rarely implement regional codes of conduct to prevent plant invasions, few have an invasive species policy, and there is limited monitoring of garden escapes. This lack of preparedness is of particular concern given the rapid increase in living collections worldwide since 1950, particularly in South America and Asia, and highlights past patterns of introduction will be a poor guide to determining future

  3. Facilitation of a native pest of rice, Stenotus rubrovittatus (Hemiptera: Miridae), by the non-native Lolium multiflorum (Cyperales: Poaceae) in an agricultural landscape.

    Science.gov (United States)

    Yoshioka, Akira; Takada, Mayura; Washitani, Izumi

    2011-10-01

    Source populations of polyphagous pests often occur on host plants other than the economically damaged crop. We evaluated the contribution of patches of a non-native meadow grass, Lolium multiflorum Lam. (Poaceae), and other weeds growing in fallow fields or meadows as source hosts of an important native pest of rice, Stenotus rubrovittatus (Matsumura) (Hemiptera: Miridae), in an agricultural landscape of northern Japan. Periodical censuses of this mirid bug by using the sweeping method, vegetation surveys, and statistical analysis revealed that L. multiflorum was the only plant species that was positively correlated with the density of adult S. rubrovittatus through two generations and thus may be the most stable and important host of the mirid bug early in the season before the colonization of rice paddies. The risk and cost of such an indirect negative effect on a crop plant through facilitation of a native pest by a non-native plant in the agricultural landscape should not be overlooked.

  4. Response of plant species to coal-mine soil materials

    Energy Technology Data Exchange (ETDEWEB)

    Day, A.D.; Tucker, T.C.; Thames, J.L.

    1983-03-01

    The two-year Black Mesa Coal Mine Research Study on the area near Kayenta, Arizona investigating the growth and establishment of seven plant species in unmined soil and coal-mined soils found that plant species grew better in unmined soil and that irrigation is essential during seedling establishment for the effective stabilization of coal-mined soils in a semi-arid environment. Differences among the species included variations in germination, response to irrigation, seedling establishment, and stem growth. 12 references, 2 figures, 2 tables.

  5. Distribution and content of ellagitannins in Finnish plant species.

    Science.gov (United States)

    Moilanen, Johanna; Koskinen, Piia; Salminen, Juha-Pekka

    2015-08-01

    The results of a screening study, in which a total of 82 Finnish plant species were studied for their ellagitannin composition and content, are presented. The total ellagitannin content was determined by HPLC-DAD, the detected ellagitannins were further characterized by HPLC-ESI-QTOF-MS and divided into four structurally different sub-groups. Thirty plant species were found to contain ellagitannins and the ellagitannin content in the crude extracts varied from few mgg(-1) to over a hundred mgg(-1). Plant families that were rich in ellagitannins (>90mgg(-1) of the crude extract) were Onagraceae, Lyhtraceae, Geraniaceae, Elaeagnaceae, Fagaceae and some species from Rosaceae. Plant species that contained moderate amounts of ellagitannins (31-89mgg(-1) of the crude extract) were representatives of the family Rosaceae. Plant species that contained low amounts of ellagitannins (1-30mgg(-1) of the crude extract) were representatives of the families Betulaceae and Myricaceae. The specific ellagitannin composition of the species allowed their chemotaxonomic classification and the comparison between the older Cronquist's classification and the nowadays preferred Angiosperm Phylogeny Group classification. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Human disturbance and upward expansion of plants in a warming climate

    Science.gov (United States)

    Dainese, Matteo; Aikio, Sami; Hulme, Philip E.; Bertolli, Alessio; Prosser, Filippo; Marini, Lorenzo

    2017-08-01

    Climate change is expected to trigger an upward expansion of plants in mountain regions and, although there is strong evidence that many native species have already shifted their distributions to higher elevations, little is known regarding how fast non-native species might respond to climate change. By analysing 131,394 occurrence records of 1,334 plant species collected over 20 years in the European Alps, we found that non-natives are spreading upwards approximately twice as fast as natives. Whereas the spread of natives was enhanced by traits favouring longer dispersal distances, this was not the case for non-natives. This was due to the non-native species pool already being strongly biased towards species that had traits facilitating spread. A large proportion of native and non-native species seemed to be able to spread upwards faster than the current velocity of climate change. In particular, long-distance dispersal events and proximity to roads proved to be key drivers for the observed rapid spread. Our findings highlight that invasions by non-native species into native alpine communities are a potentially significant additional pressure on these vulnerable ecosystems that are already likely to suffer dramatic vegetation changes with ongoing warming and increasing human activity in mountain regions.

  7. Plant Species Identification by Bi-channel Deep Convolutional Networks

    Science.gov (United States)

    He, Guiqing; Xia, Zhaoqiang; Zhang, Qiqi; Zhang, Haixi; Fan, Jianping

    2018-04-01

    Plant species identification achieves much attention recently as it has potential application in the environmental protection and human life. Although deep learning techniques can be directly applied for plant species identification, it still needs to be designed for this specific task to obtain the state-of-art performance. In this paper, a bi-channel deep learning framework is developed for identifying plant species. In the framework, two different sub-networks are fine-tuned over their pretrained models respectively. And then a stacking layer is used to fuse the output of two different sub-networks. We construct a plant dataset of Orchidaceae family for algorithm evaluation. Our experimental results have demonstrated that our bi-channel deep network can achieve very competitive performance on accuracy rates compared to the existing deep learning algorithm.

  8. Herbivory and dominance shifts among exotic and congeneric native plant species during plant community establishment

    DEFF Research Database (Denmark)

    Engelkes, Tim; Meisner, Annelein; Morriën, Elly

    2016-01-01

    in a riparian ecosystem during early establishment of invaded communities. We planted ten plant communities each consisting of three individuals of each of six exotic plant species as well as six phylogenetically related natives. Exotic plant species were selected based on a rapid recent increase in regional...... abundance, the presence of a congeneric native species, and their co-occurrence in the riparian ecosystem. All plant communities were covered by tents with insect mesh. Five tents were open on the leeward side to allow herbivory. The other five tents were completely closed in order to exclude insects...... and vertebrates. Herbivory reduced aboveground biomass by half and influenced which of the plant species dominated the establishing communities. Exposure to herbivory did not reduce the total biomass of natives more than that of exotics, so aboveground herbivory did not selectively enhance exotics during...

  9. Gopherus agassizii (Desert Tortoise). Non-native seed dispersal

    Science.gov (United States)

    Ennen, J.R.; Loughran, Caleb L.; Lovich, Jeffrey E.

    2011-01-01

    Sahara Mustard (Brassica tournefortii) is a non-native, highly invasive weed species of southwestern U.S. deserts. Sahara Mustard is a hardy species, which flourishes under many conditions including drought and in both disturbed and undisturbed habitats (West and Nabhan 2002. In B. Tellman [ed.], Invasive Plants: Their Occurrence and Possible Impact on the Central Gulf Coast of Sonora and the Midriff Islands in the Sea of Cortes, pp. 91–111. University of Arizona Press, Tucson). Because of this species’ ability to thrive in these habitats, B. tournefortii has been able to propagate throughout the southwestern United States establishing itself in the Mojave and Sonoran Deserts in Arizona, California, Nevada, and Utah. Unfortunately, naturally disturbed areas created by native species, such as the Desert Tortoise (Gopherus agassizii), within these deserts could have facilitated the propagation of B. tournefortii. (Lovich 1998. In R. G. Westbrooks [ed.], Invasive Plants, Changing the Landscape of America: Fact Book, p. 77. Federal Interagency Committee for the Management of Noxious and Exotic Weeds [FICMNEW], Washington, DC). However, Desert Tortoises have never been directly observed dispersing Sahara Mustard seeds. Here we present observations of two Desert Tortoises dispersing Sahara Mustard seeds at the interface between the Mojave and Sonoran deserts in California.

  10. Mercury uptake and accumulation by four species of aquatic plants

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Kathleen [Department of Biology, Russell Sage College, 45 Ferry Street, Troy, NY 12180 (United States)]. E-mail: skinnk@sage.edu; Wright, Nicole [NEIWPCC-NYSDEC, 625 Broadway, 4th Floor, Albany, NY 12233-3502 (United States)]. E-mail: ndwright@gw.dec.state.ny.us; Porter-Goff, Emily [Department of Biology, Russell Sage College, 45 Ferry Street, Troy, NY 12180 (United States)

    2007-01-15

    The effectiveness of four aquatic plants including water hyacinth (Eichornia crassipes), water lettuce (Pistia stratiotes), zebra rush (Scirpus tabernaemontani) and taro (Colocasia esculenta) were evaluated for their capabilities in removing mercury from water. The plants were exposed to concentrations of 0 mg/L, 0.5 mg/L or 2 mg/L of mercury for 30 days. Assays were conducted using both Microtox[reg] (water) and cold vapor Atomic Absorption Spectroscopy (AAS) (roots and water). The Microtox[reg] results indicated that the mercury induced acute toxicity had been removed from the water. AAS confirmed an increase of mercury within the plant root tissue and a corresponding decrease of mercury in the water. All species of plants appeared to reduce mercury concentrations in the water via root uptake and accumulation. Water lettuce and water hyacinth appeared to be the most effective, followed by taro and zebra rush, respectively. - Four species of aquatic plants reduced mercury in water.

  11. Mercury uptake and accumulation by four species of aquatic plants

    International Nuclear Information System (INIS)

    Skinner, Kathleen; Wright, Nicole; Porter-Goff, Emily

    2007-01-01

    The effectiveness of four aquatic plants including water hyacinth (Eichornia crassipes), water lettuce (Pistia stratiotes), zebra rush (Scirpus tabernaemontani) and taro (Colocasia esculenta) were evaluated for their capabilities in removing mercury from water. The plants were exposed to concentrations of 0 mg/L, 0.5 mg/L or 2 mg/L of mercury for 30 days. Assays were conducted using both Microtox[reg] (water) and cold vapor Atomic Absorption Spectroscopy (AAS) (roots and water). The Microtox[reg] results indicated that the mercury induced acute toxicity had been removed from the water. AAS confirmed an increase of mercury within the plant root tissue and a corresponding decrease of mercury in the water. All species of plants appeared to reduce mercury concentrations in the water via root uptake and accumulation. Water lettuce and water hyacinth appeared to be the most effective, followed by taro and zebra rush, respectively. - Four species of aquatic plants reduced mercury in water

  12. Generalist Bee Species on Brazilian Bee-Plant Interaction Networks

    Directory of Open Access Journals (Sweden)

    Astrid de Matos Peixoto Kleinert

    2012-01-01

    Full Text Available Determining bee and plant interactions has an important role on understanding general biology of bee species as well as the potential pollinating relationship between them. Bee surveys have been conducted in Brazil since the end of the 1960s. Most of them applied standardized methods and had identified the plant species where the bees were collected. To analyze the most generalist bees on Brazilian surveys, we built a matrix of bee-plant interactions. We estimated the most generalist bees determining the three bee species of each surveyed locality that presented the highest number of interactions. We found 47 localities and 39 species of bees. Most of them belong to Apidae (31 species and Halictidae (6 families and to Meliponini (14 and Xylocopini (6 tribes. However, most of the surveys presented Apis mellifera and/or Trigona spinipes as the most generalist species. Apis mellifera is an exotic bee species and Trigona spinipes, a native species, is also widespread and presents broad diet breath and high number of individuals per colony.

  13. Modulation of legume defense signaling pathways by native and non-native pea aphid clones

    Directory of Open Access Journals (Sweden)

    Carlos Sanchez-Arcos

    2016-12-01

    Full Text Available The pea aphid (Acyrthosiphon pisum is a complex of at least 15 genetically different host races that are native to specific legume plants, but can all develop on the universal host plant Vicia faba. Despite much research it is still unclear why pea aphid host races (biotypes are able to colonize their native hosts while other host races are not. All aphids penetrate the plant and salivate into plant cells when they test plant suitability. Thus plants might react differently to the various pea aphid host races. To find out whether legume species vary in their defense responses to different pea aphid host races, we measured the amounts of salicylic acid (SA, the jasmonic acid-isoleucine conjugate (JA-Ile, other jasmonate precursors and derivatives, and abscisic acid (ABA in four different species (Medicago sativa, Trifolium pratense, Pisum sativum, V. faba after infestation by native and non-native pea aphid clones of various host races. Additionally, we assessed the performance of the clones on the four plant species. On M. sativa and T. pratense, non-native clones that were barely able to survive or reproduce, triggered a strong SA and JA-Ile response, whereas infestation with native clones led to lower levels of both phytohormones. On P. sativum, non-native clones, which survived or reproduced to a certain extent, induced fluctuating SA and JA-Ile levels, whereas the native clone triggered only a weak SA and JA-Ile response. On the universal host V. faba all aphid clones triggered only low SA levels initially, but induced clone-specific patterns of SA and JA-Ile later on. The levels of the active JA-Ile conjugate and of the other JA-pathway metabolites measured showed in many cases similar patterns, suggesting that the reduction in JA signaling was due to an effect upstream of OPDA. ABA levels were downregulated in all aphid clone-plant combinations and were therefore probably not decisive factors for aphid-plant compatibility. Our results

  14. Plant-soil interactions in the expansion and native range of a poleward shifting plant species

    NARCIS (Netherlands)

    Grunsven, van R.H.A.; Putten, van der W.H.; Bezemer, T.M.; Berendse, F.; Veenendaal, E.M.

    2010-01-01

    Climate warming causes range shifts of many species toward higher latitudes and altitudes. However, range shifts of host species do not necessarily proceed at the same rates as those of their enemies and symbionts. Here, we examined how a range shifting plant species performs in soil from its

  15. Plant species richness regulates soil respiration through changes in productivity.

    Science.gov (United States)

    Dias, André Tavares Corrêa; van Ruijven, Jasper; Berendse, Frank

    2010-07-01

    Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of diversity on soil respiration. We hypothesized that plant diversity could affect soil respiration in two ways. On the one hand, more diverse plant communities have been shown to promote plant productivity, which could increase soil respiration. On the other hand, the nutrient concentration in the biomass produced has been shown to decrease with diversity, which could counteract the production-induced increase in soil respiration. Our results clearly show that soil respiration increased with species richness. Detailed analysis revealed that this effect was not due to differences in species composition. In general, soil respiration in mixtures was higher than would be expected from the monocultures. Path analysis revealed that species richness predominantly regulates soil respiration through changes in productivity. No evidence supporting the hypothesized negative effect of lower N concentration on soil respiration was found. We conclude that shifts in productivity are the main mechanism by which changes in plant diversity may affect soil respiration.

  16. Assessing the consequences of nonnative trout in headwater ecosystems in western North America

    Science.gov (United States)

    Jason B. Dunham; David S. Pilliod; Michael K. Young

    2004-01-01

    Intentional introductions of nonnative trout into headwater lakes and streams can have numerous effects on the receiving ecosystems, potentially threatening native species and disrupting key ecological processes. In this perspective, we focus on seven key issues for assessing the biological and economic consequences of nonnative trout in headwater ecosystems: (1)...

  17. Floristic summary of plant species in the air pollution literature.

    Science.gov (United States)

    Bennett, J P

    1996-01-01

    A floristic summary and analysis was performed on a list of the plant species that have been studied for the effects of gaseous and chemical air pollutants on vegetation in order to compare the species with the flora of North America north of Mexico. The scientific names of 2081 vascular plant species were extracted from almost 4000 journal articles stored in two large literature databases on the effects of air pollutants on plants. Three quarters of the plant species studied occur in North America, but this was only 7% of the total North American flora. Sixteen percent and 56% of all North American genera and families have been studied. The most studied genus is Pinus with 70% of the North American species studied, and the most studied family is the grass family, with 12% of the species studied. Although Pinus is ranked 86th in the North American flora, the grass family is ranked third, indicating that representation at the family level is better than at the genus level. All of the top ten families in North America are represented in the top 20 families in the air pollution effects literature, but only one genus (Lupinus) in the top ten genera in North America is represented in the top thirteen genera in the air pollution literature.

  18. Differential Response of a Local Population of Entomopathogenic Nematodes to Non-Native Herbivore Induced Plant Volatiles (HIPV) in the Laboratory and Field.

    Science.gov (United States)

    Rivera, Monique J; Rodriguez-Saona, Cesar; Alborn, Hans T; Koppenhöfer, Albrecht M

    2016-12-01

    Recent work has shown the potential for enhanced efficacy of entomopathogenic nematodes (EPN) through their attraction to herbivore induced plant volatiles. However, there has been little investigation into the utilization of these attractants in systems other than in those in which they were identified. We compared (E)-β-caryophyllene and pregeijerene in the highbush blueberry (Vaccinium corymbosum) agroecosystem in their ability to enhance the attraction of EPN to and efficacy against the system's herbivore, oriental beetle (Anomala orientalis). The relative attractiveness of (E)-β-caryophyllene and pregeijerene to a local isolate of the EPN species Steinernema glaseri was tested in a six-arm olfactometer in the laboratory to gather baseline values of attraction to the chemicals alone in sand substrate before field tests. A similar arrangement was used in a V. corymbosum field by placing six cages with assigned treatments and insect larvae with and without compound into the soil around the base of 10 plants. The cages were removed after 72 h, and insect baits were retrieved and assessed for EPN infection. The lab results indicate that in sand alone (E)-β-caryophyllene is significantly more attractive than pregeijerene to the local S. glaseri isolate Conversely, there was no difference in attractiveness in the field study, but rather, native S. glaseri were more attracted to cages with G. mellonella larvae, no larvae, and cages with the blank control and G. mellonella larvae.

  19. The role of CVS (and FIA) data and genetic tests in assessing species vulnerability to invasive pests and changing climate

    Science.gov (United States)

    R.A. Sniezko; H.E. Lintz

    2017-01-01

    United States tree species and their associated ecosystems, managed forests, and urban plantings are increasingly vulnerable to non-native invasive pathogens and insects as well as effects associated with a changing climate. Some species, such as whitebark pine (Pinus albicaulis), have been proposed for listing under the Endangered Species Act. To...

  20. Invasive vascular plant species of limnocrenic karst springs in Poland

    Science.gov (United States)

    Spałek, Krzysztof

    2015-04-01

    Natural water reservoirs are very valuable floristic sites in Poland. Among them, the most important for preservation of biodiversity of flora are limnocrenic karst springs. The long-term process of human pressure on habitats of this type caused disturbance of their biological balance. Changes in the water regime, industrial development and chemisation of agriculture, especially in the period of last two hundred years, led to systematic disappearance of localities of many plant species connected with rare habitats and also to appear numerous invasive plant species. They are: Acorus calamus, Echinocystis lobata, Elodea canadensis, Erechtites hieraciifolia, Impatiens glandulifera, Solidago canadensis, S. gigantea and S. graminifolia. Fielworks were conducted in 2010-2014.

  1. Plant antiherbivore defenses in Fabaceae species of the Chaco.

    Science.gov (United States)

    Lima, T E; Sartori, A L B; Rodrigues, M L M

    2017-01-01

    The establishment and maintenance of plant species in the Chaco, one of the widest continuous areas of forests in the South American with sharp climatic variations, are possibly related to biological features favoring plants with particular defenses. This study assesses the physical and chemical defenses mechanisms against herbivores of vegetative and reproductive organs. Its analyses of 12 species of Fabaceae (Leguminosae) collected in remnants of Brazilian Chaco shows that 75% present structural defense characters and 50% have chemical defense - defense proteins in their seeds, like protease inhibitors and lectins. Physical defenses occur mainly on branches (78% of the species), leaves (67%), and reproductive organs (56%). The most common physical characters are trichomes and thorns, whose color represents a cryptic character since it does not contrast with the other plant structures. Defense proteins occur in different concentrations and molecular weight classes in the seeds of most species. Protease inhibitors are reported for the first time in seeds of: Albizia niopoides, Anadenanthera colubrina, Mimosa glutinosa, Prosopis rubriflora, and Poincianella pluviosa. The occurrence of physical and chemical defenses in members of Fabaceae indicate no associations between defense characters in these plant species of the Chaco.

  2. Nonnative Fishes in the Upper Mississippi River System

    Science.gov (United States)

    Irons, Kevin S.; DeLain, Steven A.; Gittinger, Eric; Ickes, Brian S.; Kolar, Cindy S.; Ostendort, David; Ratcliff, Eric N.; Benson, Amy J.; Irons, Kevin S.

    2009-01-01

    The introduction, spread, and establishment of nonnative species is widely regarded as a leading threat to aquatic biodiversity and consequently is ranked among the most serious environmental problems facing the United States today. This report presents information on nonnative fish species observed by the Long Term Resource Monitoring Program on the Upper Mississippi River System a nexus of North American freshwater fish diversity for the Nation. The Long Term Resource Monitoring Program, as part of the U.S. Army Corps of Engineers' Environmental Management Plan, is the Nation's largest river monitoring program and stands as the primary source of standardized ecological information on the Upper Mississippi River System. The Long Term Resource Monitoring Program has been monitoring fish communities in six study areas on the Upper Mississippi River System since 1989. During this period, more than 3.5 million individual fish, consisting of 139 species, have been collected. Although fish monitoring activities of the Long Term Resource Monitoring Program focus principally on entire fish communities, data collected by the Program are useful for detecting and monitoring the establishment and spread of nonnative fish species within the Upper Mississippi River System Basin. Sixteen taxa of nonnative fishes, or hybrids thereof, have been observed by the Long Term Resource Monitoring Program since 1989, and several species are presently expanding their distribution and increasing in abundance. For example, in one of the six study areas monitored by the Long Term Resource Monitoring Program, the number of established nonnative species has increased from two to eight species in less than 10 years. Furthermore, contributions of those eight species can account for up to 60 percent of the total annual catch and greater than 80 percent of the observed biomass. These observations are critical because the Upper Mississippi River System stands as a nationally significant pathway for

  3. Can transgenerational plasticity contribute to the invasion success of annual plant species?

    Science.gov (United States)

    Fenesi, Annamária; Dyer, Andrew R; Geréd, Júliánna; Sándor, Dorottya; Ruprecht, Eszter

    2014-09-01

    Adaptive transgenerational plasticity (TGP), i.e., significantly higher fitness when maternal and offspring conditions match, might contribute to the population growth of non-native species in highly variable environments. However, comparative studies that directly test this hypothesis are lacking. Therefore, we performed a reciprocal split-brood experiment to compare TGP in response to N and water availability in single populations of two invasive (Amaranthus retroflexus, Galinsoga parviflora) and two congeneric non-invasive introduced species (Amaranthus albus, Galinsoga ciliata). We hypothesized that the transgenerational effect is adaptive: (1) in invasive species compared with non-invasive adventives, and (2) in stressful conditions compared with resource-rich environments. The phenotypic variation among offspring was generated, in large part, by our experimental treatments in the maternal generation; therefore, we demonstrated a direct TGP effect on the offspring's adult fitness. We found evidence, for the first time, that invasive and non-invasive adventive species differ regarding the expression of TGP in the adult stage, as adaptive responses were found exclusively in the invasive species. The manifestation of TGP was more explicit under resource-rich conditions; therefore, it might contribute to the population dynamics of non-native species in resource-rich sites rather than to their ecological tolerance spectra.

  4. 77 FR 49893 - Endangered and Threatened Wildlife and Plants; Determination of Status for the Gierisch Mallow...

    Science.gov (United States)

    2012-08-17

    ... impacts, such as regulations governing mining operations; The spread of nonnative, invasive plant species... gypsum mining necessarily involves removal of the topsoil, eliminating, at least temporarily, the species..., invasive species such as cheatgrass and red brome. Livestock have been implicated in the spread of weeds...

  5. Relationships between Plant Biomass and Species Richness under ...

    African Journals Online (AJOL)

    The study was conducted in a montane grassland of Kokosa District, West Arsi Zone of Oromia Region, southern Ethiopia. The objective of the study was to investigate the relationships between aboveground plant biomass and species richness in three farming systems and four grazing management systems. A total of 180 ...

  6. Regional Assessment of Ozone Sensitive Tree Species Using Bioindicator Plants

    Science.gov (United States)

    John W. Coulston; Gretchen C. Smith; William D. Smith

    2003-01-01

    Tropospheric ozone occurs at phytotoxic levels in the northeastern and mid-Atlantic regions of the United States. Quantifying possible regional-scale impacts of ambient ozone on forest tree species is difficult and is confounded by other factors, such as moisture and light, which influence the uptake of ozone by plants. Biomonitoring provides an approach to document...

  7. Extraction and antioxidant activities of two species Origanum plant ...

    African Journals Online (AJOL)

    The antioxidant of ethanolic extract of two species of Origanum and essential oil of plant Origanum vulgare were investigated and also the total phenolic and flavonoid content measured. The radical scavenging activity was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Total phenolic and flavonoid ...

  8. Widespread plant species: natives versus aliens in our changing world

    Czech Academy of Sciences Publication Activity Database

    Stohlgren, T. J.; Pyšek, Petr; Kartesz, J.; Nishino, M.; Pauchard, A.; Winter, M.; Pino, J.; Richardson, D. M.; Wilson, J. R. U.; Murray, B. R.; Phillips, M. L.; Ming-yang, L.; Celesti-Grapow, L.; Font, X.

    2011-01-01

    Roč. 13, č. 9 (2011), s. 1931-1944 ISSN 1387-3547 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60050516 Keywords : plant invasions * species distribution * Old and New World Subject RIV: EF - Botanics Impact factor: 2.896, year: 2011

  9. The importance of education in managing invasive plant species

    Science.gov (United States)

    Invasive plant species can establish in diverse environments and with the increase in human mobility, they are no longer restricted to isolated pockets in remote parts of the world. Cheat grass (Bromus tectorum L.) in rangelands, purple loosestrife (Lythrum salicaria L.) in wet lands and Canada this...

  10. AIRBORNE HYPERSPECTRAL IDENTIFICATION OF INVASIVE AND OPPORTUNISTIC WETLANDS PLANT SPECIES

    Science.gov (United States)

    Coastal wetlands are among the most fragmented and disturbed ecosystems and the Great Lakes are no exception. One possible result is the observed increase in the presence and dominance of invasive and other opportunistic plant species, such as the common reed (Phragmites australi...

  11. Ecotaxonmic baseline evaluation of the plant species in a ...

    African Journals Online (AJOL)

    The survey of the flora composition of an ecosystem is important in several environmental baseline studies. An ecotaxonomic assessment was carried out in Ase-Ndoni proposed Rivgas Refinery project site in other to find out the plant species of medicinal and other economic values. The investigation was carried out to ...

  12. Rare and Endangered Geophyte Plant Species in Serpentine of Kosovo

    Directory of Open Access Journals (Sweden)

    Naim Berisha

    2014-12-01

    Full Text Available Our study documents information on rarity, geographical distribution, taxonomy and conservation status of 11 geophyte species in serpentine soils of Kosovo, already included in the Red Book of Vascular Flora of Kosovo. Kosovo’s serpentine vegetation represents a diversity that yet has not been sufficiently explored. Large serpentine complexes are found in the northern Kosovo but also southern part of the country is rich in serpentines, therefore in endemics. Serpentine rocks and soils are characterized by low level of principal plant nutrients (N, P, K, Ca and exceptionally high levels of Mg and Fe. Serpentines play particular importance for flora of the country due to their richness in endemic plant species. The following 11 plant species have been studied: Aristolochia merxmuelleri, Colchicum hungaricum, Crocus flavus, Crocus kosaninii, Epimedium alpinum, Gentiana punctata, Gladiolus illyricus, Lilium albanicum, Paeonia peregrina, Tulipa gesneriana and Tulipa kosovarica. Five out of eleven studied geophytes fall within Critically Endangered IUCN based threat category and five out of eleven are local endemics. Aristolochia merxmuelleri and Tulipa kosovarica are steno-endemic plant species that are found exclusively in serpentine soils. Information in our database should prove to be valuable to efforts in ecology, floristics, biosystematics, conservation and land management.

  13. Blending ecology and evolution using emerging technologies to determine species distributions with a non-native pathogen in a changing climate

    Science.gov (United States)

    K. Waring; S. Cushman; A. Eckert; L. Flores-Renteria; H. Lintz; R. Sniezko; C. Still; C. Wehenkel; A. Whipple; M. Wing

    2017-01-01

    A collaborative team of researchers from the United States and Mexico has begun an exciting new research project funded by The National Science Foundation’s Macrosystems Biology program. The project will study ecological and evolutionary processes affecting the distribution of southwestern white pine (Pinus strobiformis), an important tree species of mixed conifer...

  14. Efficient distinction of invasive aquatic plant species from non-invasive related species using DNA barcoding.

    Science.gov (United States)

    Ghahramanzadeh, R; Esselink, G; Kodde, L P; Duistermaat, H; van Valkenburg, J L C H; Marashi, S H; Smulders, M J M; van de Wiel, C C M

    2013-01-01

    Biological invasions are regarded as threats to global biodiversity. Among invasive aliens, a number of plant species belonging to the genera Myriophyllum, Ludwigia and Cabomba, and to the Hydrocharitaceae family pose a particular ecological threat to water bodies. Therefore, one would try to prevent them from entering a country. However, many related species are commercially traded, and distinguishing invasive from non-invasive species based on morphology alone is often difficult for plants in a vegetative stage. In this regard, DNA barcoding could become a good alternative. In this study, 242 samples belonging to 26 species from 10 genera of aquatic plants were assessed using the chloroplast loci trnH-psbA, matK and rbcL. Despite testing a large number of primer sets and several PCR protocols, the matK locus could not be amplified or sequenced reliably and therefore was left out of the analysis. Using the other two loci, eight invasive species could be distinguished from their respective related species, a ninth one failed to produce sequences of sufficient quality. Based on the criteria of universal application, high sequence divergence and level of species discrimination, the trnH-psbA noncoding spacer was the best performing barcode in the aquatic plant species studied. Thus, DNA barcoding may be helpful with enforcing a ban on trade of such invasive species, such as is already in place in the Netherlands. This will become even more so once DNA barcoding would be turned into machinery routinely operable by a nonspecialist in botany and molecular genetics. © 2012 Blackwell Publishing Ltd.

  15. Ecological Performances of Plant Species of Halophilous Hydromorphic Ecosystems

    Directory of Open Access Journals (Sweden)

    Maria Speranza

    2015-12-01

    Full Text Available Coastal wetlands are very special environments, characterized by soils permanently or seasonally saturated by salt or brackish water. They host microorganisms and plants able to adapt to anoxic conditions. This paper proposes a review of recent scientific papers dealing with the study of coastal wetlands from different points of view. Some studies examine the species composition and the pattern of the spatial distribution of plant communities, depending on the depth of the salt water table, as well as on other related factors. A significant number of studies analyse instead the coastal wetlands in their ability for the phytoremediation (phytostabilisation and/or phytoextraction and highlight the importance of interactions between the rhizosphere of the halophytes and the physical environment. Finally, more recent studies consider the plant species of the coastal wetlands as a source of useful products (food, feed, oils and expose the results of promising researches on their cultivation.

  16. Plant species richness and ecosystem multifunctionality in global drylands

    Science.gov (United States)

    Maestre, Fernando T.; Quero, Jose L.; Gotelli, Nicholas J.; Escudero, Adrian; Ochoa, Victoria; Delgado-Baquerizo, Manuel; Garcia-Gomez, Miguel; Bowker, Matthew A.; Soliveres, Santiago; Escolar, Cristina; Garcia-Palacios, Pablo; Berdugo, Miguel; Valencia, Enrique; Gozalo, Beatriz; Gallardo, Antonio; Aguilera, Lorgio; Arredondo, Tulio; Blones, Julio; Boeken, Bertrand; Bran, Donaldo; Conceicao, Abel A.; Cabrera, Omar; Chaieb, Mohamed; Derak, Mchich; Eldridge, David J.; Espinosa, Carlos I.; Florentino, Adriana; Gaitan, Juan; Gatica, M. Gabriel; Ghiloufi, Wahida; Gomez-Gonzalez, Susana; Gutie, Julio R.; Hernandez, Rosa M.; Huang, Xuewen; Huber-Sannwald, Elisabeth; Jankju, Mohammad; Miriti, Maria; Monerris, Jorge; Mau, Rebecca L.; Morici, Ernesto; Naseri, Kamal; Ospina, Abelardo; Polo, Vicente; Prina, Anibal; Pucheta, Eduardo; Ramirez-Collantes, David A.; Romao, Roberto; Tighe, Matthew; Torres-Diaz, Cristian; Val, James; Veiga, Jose P.; Wang, Deli; Zaady, Eli

    2012-01-01

    Experiments suggest that biodiversity enhances the ability of ecosystems to maintain multiple functions, such as carbon storage, productivity, and the buildup of nutrient pools (multifunctionality). However, the relationship between biodiversity and multifunctionality has never been assessed globally in natural ecosystems. We report here on a global empirical study relating plant species richness and abiotic factors to multifunctionality in drylands, which collectively cover 41% of Earth's land surface and support over 38% of the human population. Multifunctionality was positively and significantly related to species richness. The best-fitting models accounted for over 55% of the variation in multifunctionality and always included species richness as a predictor variable. Our results suggest that the preservation of plant biodiversity is crucial to buffer negative effects of climate change and desertification in drylands.

  17. The Role of Different Agricultural Plant Species in Air Pollution

    Science.gov (United States)

    Fiala, P.; Miller, D.; Shivers, S.; Pusede, S.; Roberts, D. A.

    2017-12-01

    The goal of this research project is to use remote sensing data to study the relationship between different plant species and the pollutants in the air. It is known that chemical reactions within plants serve as both sources and sinks for different types of Volatile Organic Compounds. However, the species-specific relationships have not been well studied. Through the better characterization of this relationship, certain aspects of air pollution may be more effectively managed. For this project, I used Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data and trace gas measurements from instruments on board the NASA DC-8 to assess the relationship between different plant species and the pollutants in the air. I used measurements primarily from the agricultural land surrounding Bakersfield, CA. I created a map of the crop species in this area using Multiple Endmember Spectral Mixture Analysis (MESMA) on the AVIRIS imagery, and matched this to trace gas measurements taken on the DC-8. I used a Hysplit matrix trajectory to account for the air transport over the vegetation and up to contact with the plane. Finally, I identified correlations between the plant types and the concentration of the pollutants. The results showed that there were significant relationships between specific species and pollutants, with lemons and grapes contributing to enhanced pollution, and tree nuts reducing pollution. Specifically, almonds produced significantly lower levels of O3 , NO, and NO2. Lemons and grapes had high O3 levels, and lemons had high levels of isoprene. In total, these data show that it may be possible to mitigate airborne pollution via selective planting; however, the overall environmental effects are much more complicated and must be analyzed further.

  18. Non-native grass removal and shade increase soil moisture and seedling performance during Hawaiian dry forest restoration

    Science.gov (United States)

    Jared M. Thaxton; Susan Cordell; Robert J. Cabin; Darren R. Sandquist

    2012-01-01

    Invasive non-native species can create especially problematic restoration barriers in subtropical and tropical dry forests. Native dry forests in Hawaii presently cover less than 10% of their original area. Many sites that historically supported dry forest are now completely dominated by non-native species, particularly grasses. Within a grass-dominated site in leeward...

  19. Monitoring the effects of atmospheric ethylene near polyethylene manufacturing plants with two sensitive plant species

    NARCIS (Netherlands)

    Tonneijck, A.E.G.; Berge, ten W.F.; Jansen, B.P.

    2003-01-01

    Data of a multi-year (1977-1983) biomonitoring programme with marigold and petunia around polyethylene manufacturing plants was analysed to assess plant responses to atmospheric ethylene and to determine the area at risk for the phytotoxic effects of this pollutant. In both species, flower formation

  20. Invasive non-native species of fish in upper Paraná river Basin, Brazil: variations of caloric content in Cichla kelberi

    Directory of Open Access Journals (Sweden)

    Luis Alberto Espínola

    Full Text Available The allocation of assimilated energy may be influenced by seasonal changes, growth, and reproductive cycle of fish, food consumption and environmental conditions. The objective of this research was to evaluate the energetic variations of Cichla kelberi in the upper Paraná River floodplain, analyzing the caloric content in muscles, gonadosomatic index (GSI, and the condition factor between assessed systems, sex, and stage of gonadal maturation. The results obtained in the present study permit assuring that this is a species that efficiently converts the resources of the environment into energy. Although presenting higher condition factor in the environment where there is a greater ease in getting food (Paraná subsystem, the energy identified in the muscles was the same in both subsystems. During the process of gonadal maturation there is optimization in energy accumulation in the muscles of females, before and after reproductive period, and somatic growth occurs significantly when the individual is not reproducing. Further detailed studies on ecological mechanisms influencing the success of the species, as the presence of competitors and preference for native preys, are needed to implement effective management measures aimed at preventing that the species proliferation in the environment is even more damaging to local biodiversity.

  1. Mercury uptake and accumulation by four species of aquatic plants.

    Science.gov (United States)

    Skinner, Kathleen; Wright, Nicole; Porter-Goff, Emily

    2007-01-01

    The effectiveness of four aquatic plants including water hyacinth (Eichornia crassipes), water lettuce (Pistia stratiotes), zebra rush (Scirpus tabernaemontani) and taro (Colocasia esculenta) were evaluated for their capabilities in removing mercury from water. The plants were exposed to concentrations of 0 mg/L, 0.5 mg/L or 2 mg/L of mercury for 30 days. Assays were conducted using both Microtox (water) and cold vapor Atomic Absorption Spectroscopy (AAS) (roots and water). The Microtox results indicated that the mercury induced acute toxicity had been removed from the water. AAS confirmed an increase of mercury within the plant root tissue and a corresponding decrease of mercury in the water. All species of plants appeared to reduce mercury concentrations in the water via root uptake and accumulation. Water lettuce and water hyacinth appeared to be the most effective, followed by taro and zebra rush, respectively.

  2. Long-term changes in communities of native coccinellids: population fluctuations and the effect of competition from an invasive non-native species

    Czech Academy of Sciences Publication Activity Database

    Honěk, A.; Martínková, Z.; Dixon, Anthony F. G.; Roy, H. E.; Pekárek, S.

    2016-01-01

    Roč. 9, č. 3 (2016), s. 202-209 ISSN 1752-458X R&D Projects: GA ČR GA14-26561S; GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : ladybird harmonia-axyridis * coleoptera-coccinellidae * intraguild predation * habitat preferences * central-europe * spread * ladybeetle * beetles * history * decline * Adalia * Anatis * Calvia * Coccinella * Halyzia * Harmonia * intraguild predation * invasive alien species * ladybird beetles * Propylea Subject RIV: EH - Ecology, Behaviour Impact factor: 1.840, year: 2016

  3. Light dependency of VOC emissions from selected Mediterranean plant species

    Science.gov (United States)

    Owen, S. M.; Harley, P.; Guenther, A.; Hewitt, C. N.

    The light, temperature and stomatal conductance dependencies of volatile organic compound (VOC) emissions from ten plant species commonly found in the Mediterranean region were studied using a fully controlled leaf cuvette in the laboratory. At standard conditions of temperature and light (30°C and 1000 μmol m -2 s -1 PAR), low emitting species ( Arbutus unedo, Pinus halepensis, Cistus incanus, Cistus salvifolius, Rosmarinus officinalis and Thymus vulgaris) emitted between 0.1 and 5.0 μg (C) (total VOCs) g -1 dw h -1, a medium emitter ( Pinus pinea) emitted between 5 and 10 μg (C) g -1 dw h -1 and high emitters ( Cistus monspeliensis, Lavendula stoechas and Quercus sp.) emitted more than 10 μg (C) g -1 dw h -1. VOC emissions from all of the plant species investigated showed some degree of light dependency, which was distinguishable from temperature dependency. Emissions of all compounds from Quercus sp. were light dependent. Ocimene was one of several monoterpene compounds emitted by P. pinea and was strongly correlated to light. Only a fraction of monoterpene emissions from C. incanus exhibited apparent weak light dependency but emissions from this plant species were strongly correlated to temperature. Data presented here are consistent with past studies, which show that emissions are independent of stomatal conductance. These results may allow more accurate predictions of monoterpene emission fluxes from the Mediterranean region to be made.

  4. Latitudinal shifts of introduced species: possible causes and implications

    Science.gov (United States)

    Qinfeng Guo; Dov F. Sax; Hong Qian; Regan Early

    2012-01-01

    This study aims to document shifts in the latitudinal distributions of non-native species relative to their own native distributions and to discuss possible causes and implications of these shifts. We used published and newly compiled data on intercontinentally introduced birds, mammals and plants. We found strong correlations between the latitudinal distributions...

  5. INAA of microelements in plant species from the Danube floodplain

    Energy Technology Data Exchange (ETDEWEB)

    Pantelica, A; Salagean, M; Scarlat, A [Department of Applie Physics, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-76900 Magurele-Bucharest (Romania); Iordache, V [Department of Ecology, University of Bucharest, Bucharest (Romania)

    1999-07-01

    A research was developed and implemented in the Danube floodplain, as a part of a program dealing with biogeochemistry of metals, to assess the possibility of using the ubiquitous plant species in the soil pollution monitoring activity. The Danube River is heavily polluted by the input from a catchment, which includes 12 countries. Even if the concentrations in the Danube water and sediments reach acute values only in some hot spots, due to the dilution effect, they could have negative consequences by phenomena of bioaccumulation and bioconcentration. The content of Al, Ag, As, Au, Ba, Br, Ca, Cl, Ce, Co, Cr, Cs, Cu, Eu, Fe, Hg, Hf, K, La, Mg, Mn, Na, Ni, Rb, Sc, Se, Sm, Sr, Th, V and Zn in Bidens tripartita, Rubus caesius, Stachys palustris and Xanthium strumarium ubiquitous plant species, collected from two areas located on different regularly flooded islands of the Danube river was investigated by instrumental neutron activation analysis method at WWR-S reactor in Bucharest. From the statistical point of view, three groups of elements present highly correlated concentrations in the investigated plant samples (p(0.05))//. The first one includes Al, As, Ce, Cs, Eu, Fe, Hf, La, Sc, Sm, Th and V, the second one Au, Ca, Cu and Sr, and the third one Br, Cr, Na and Mn. For the elements of the first group, the elemental concentrations are found to be in similar ratios in the species investigated, namely: Xanthium s. < Rubus c. < Bidens t. < Stachys p. as well as for the third group: Bidens t. < Rubus c. < Stachys p. < Xanthium s, suggesting that physiological features of the species could be responsible for the observed patterns of distribution. The soil and dominating plant species were analysed for Cr, Cu, Fe, Mn, Ni, Pb, Zn and Zr by the X-ray fluorescence method at the Institute for Geological Explorations, Bucharest. The elemental content in soil is reflected in the analysed plants for Cr, Cu, Fe, Ni, Pb and Zn, but not for Mn. This could be explained by the redox

  6. INAA of microelements in plant species from the Danube floodplain

    International Nuclear Information System (INIS)

    Pantelica, A.; Salagean, M.; Scarlat, A.; Iordache, V.

    1999-01-01

    A research was developed and implemented in the Danube floodplain, as a part of a program dealing with biogeochemistry of metals, to assess the possibility of using the ubiquitous plant species in the soil pollution monitoring activity. The Danube River is heavily polluted by the input from a catchment, which includes 12 countries. Even if the concentrations in the Danube water and sediments reach acute values only in some hot spots, due to the dilution effect, they could have negative consequences by phenomena of bioaccumulation and bioconcentration. The content of Al, Ag, As, Au, Ba, Br, Ca, Cl, Ce, Co, Cr, Cs, Cu, Eu, Fe, Hg, Hf, K, La, Mg, Mn, Na, Ni, Rb, Sc, Se, Sm, Sr, Th, V and Zn in Bidens tripartita, Rubus caesius, Stachys palustris and Xanthium strumarium ubiquitous plant species, collected from two areas located on different regularly flooded islands of the Danube river was investigated by instrumental neutron activation analysis method at WWR-S reactor in Bucharest. From the statistical point of view, three groups of elements present highly correlated concentrations in the investigated plant samples (p(0.05))//. The first one includes Al, As, Ce, Cs, Eu, Fe, Hf, La, Sc, Sm, Th and V, the second one Au, Ca, Cu and Sr, and the third one Br, Cr, Na and Mn. For the elements of the first group, the elemental concentrations are found to be in similar ratios in the species investigated, namely: Xanthium s. < Rubus c. < Bidens t. < Stachys p. as well as for the third group: Bidens t. < Rubus c. < Stachys p. < Xanthium s, suggesting that physiological features of the species could be responsible for the observed patterns of distribution. The soil and dominating plant species were analysed for Cr, Cu, Fe, Mn, Ni, Pb, Zn and Zr by the X-ray fluorescence method at the Institute for Geological Explorations, Bucharest. The elemental content in soil is reflected in the analysed plants for Cr, Cu, Fe, Ni, Pb and Zn, but not for Mn. This could be explained by the redox

  7. Establishment of native species on a natural gas pipeline: the importance of seeding rate, aspect, and species selection

    Science.gov (United States)

    Melissa A. Thomas-Van Gundy; Pamela J. Edwards; Thomas M. Schuler

    2018-01-01

    With the increase in natural gas production in the United States, land managers need solutions and best practices to mitigate potential negative impacts of forest and soil disturbance and meet landowner objectives and desired conditions. Mitigation often includes the use of native seed mixes for maintaining plant diversity, controlling nonnative invasive species, and...

  8. CE of phytosiderophores and related metal species in plants.

    Science.gov (United States)

    Xuan, Yue; Scheuermann, Enrico B; Meda, Anderson R; Jacob, Peter; von Wirén, Nicolaus; Weber, Günther

    2007-10-01

    Phytosiderophores (PS) and the closely related substance nicotianamine (NA) are key substances in metal uptake into graminaceous plants. Here, the CE separation of these substances and related metal species is demonstrated. In particular, the three PS 2'-deoxymugineic acid (DMA), mugineic acid (MA), and 3-epi-hydroxymugineic acid (epi-HMA), and NA, are separated using MES/Tris buffer at pH 7.3. Moreover, three Fe(III) species of the different PS are separated without any stability problems, which are often present in chromatographic analyses. Also divalent metal species of Cu, Ni, and Zn with the ligands DMA and NA are separated with the same method. By using a special, zwitterionic CE capillary, even the separation of two isomeric Fe(III) chelates with the ligand ethylenediamine-N,N'-bis(o-hydroxyphenyl)acetic acid (EDDHA) is possible (i.e., meso-Fe(III)-EDDHA and rac-Fe(III)-EDDHA), and for fast separations of NA and respective divalent and trivalent metal species, a polymer CE microchip with suppressed EOF is described. The proposed CE method is applicable to real plant samples, and enables to detect changes of metal species (Cu-DMA, Ni-NA), which are directly correlated to biological processes.

  9. Efficient distinction of invasive aquatic plant species from non-invasive related species using DNA barcoding

    NARCIS (Netherlands)

    Ghahramanzadeh, R.; Esselink, G.; Kodde, L.P.; Duistermaat, H.; Valkenburg, van J.L.C.H.; Marashi, S.H.; Smulders, M.J.M.; Wiel, van de C.C.M.

    2013-01-01

    Biological invasions are regarded as threats to global biodiversity. Among invasive aliens, a number of plant species belonging to the genera Myriophyllum, Ludwigia and Cabomba, and to the Hydrocharitaceae family pose a particular ecological threat to water bodies. Therefore, one would try to

  10. New evidence for electrotropism in some plant species

    Science.gov (United States)

    Gorgolewski, S.; Rozej, B.

    The ever-present global Atmospheric Electrical F ield (AEF) is used by many plant species. There are many natural habitats with electrotropic plants and habitats with no AEF. The plants growing there are not electrotropic, like the plants growing under the canopies of the trees or the Arecibo radio telescope. Examples are given of different plants which belong to one or the other class, and the criteria how to distinguish them. In addition to natural habitat observations, laboratory experiments were run in search of the sensitivity to electrotropic effect in different electric field intensities and directions. It was established that in very strong fields (of the order of 1 MV/m) all plants respond immediately to the field. This type of reaction is due to the Coulomb forces, but electrotropism depends on electric field interaction with ions in plant tissues. We use a "reference field" (130 V/m) and stronger fields in the several kV/m range which enhance plant growth rate and size similar to plant growth hormones. Surprising effects were also observed with reversed field polarity. In conclusion electrotropic pl nts deprived of the electrical field do not develop asa expected, as can be seen in BIOSPHERE 2. It was a sad example of what happens when one forgets to provide the plants with this vital natural environmental factor. Electrical fields of different intensity and direction are cheap and easy to generate. More plants were investigated in order to verify their response to electrical fields. Effect of several kV/m horizontal fields, was compared with the vertical 130 V/m field (ued as a reference) and it was shown that electrotropic sensitivity can be found easily. Surprisingly even the nonelectrotropic plants, whose initial growth rate does not depend on the field strength, when they develop leaves begin to lean towards the positive electrode, and become elect rotropic. Ground based fitotron experiments enable us to select cheaply plants which shall be suitable

  11. Climatic niche of Selinum alatum (Apiaceae, Selineae), a new invasive plant species in Central Europe and its alterations according to the climate change scenarios: Are the European mountains threatened by invasion?

    Science.gov (United States)

    Konowalik, Kamil; Proćków, Małgorzata; Proćków, Jarosław

    2017-01-01

    In recent years, a few established populations of Selinum alatum have been found in the Eastern Carpathians outside its native range that is the Caucasus and the Armenian Highlands. The species is spreading predominantly in Poland where it can outcompete native plants in certain cases. This study addresses a potential climatic niche of the plant with the special aims to illuminate future spreading and indicate areas suitable for invasion. Our results show that the extent of the favourable habitat of the species is broader than currently known. This suggests that the plant has the ability to become a potential new element in some semi-natural or disturbed ecosystems associated with mountainous areas, especially in Central and Southern Europe. Future (2070) models mostly rendered similar suitability maps, but showed slight differences over particular areas and a contraction of suitable habitats, mainly in the northern part of the non-native range.

  12. Grassland Arthropods Are Controlled by Direct and Indirect Interactions with Cattle but Are Largely Unaffected by Plant Provenance.

    Science.gov (United States)

    Farrell, Kelly Anne; Harpole, W Stanley; Stein, Claudia; Suding, Katharine N; Borer, Elizabeth T

    2015-01-01

    Cattle grazing and invasion by non-native plant species are globally-ubiquitous changes occurring to plant communities that are likely to reverberate through whole food webs. We used a manipulative field experiment to quantify how arthropod community structure differed in native and non-native California grassland communities in the presence and absence of grazing. The arthropod community was strongly affected by cattle grazing: the biovolume of herbivorous arthropods was 79% higher in grazed than ungrazed plots, whereas the biovolume of predatory arthropods was 13% higher in ungrazed plots. In plots where non-native grasses were grazed, arthropod biovolume increased, possibly in response to increased plant productivity or increased nutritional quality of rapidly-growing annual plants. Grazing may thus affect plant biomass both through the direct removal of biomass, and through arthropod-mediated impacts. We also expected the arthropod community to differ between native and non-native plant communities; surprisingly, arthropod richness and diversity did not vary consistently between these grass community types, although arthropod abundance was slightly higher in plots with native and ungrazed grasses. These results suggest that whereas cattle grazing affects the arthropod community via direct and indirect pathways, arthropod community changes commonly associated with non-native plant invasions may not be due to the identity or dominance of the invasive species in those systems, but to accompanying changes in plant traits or functional group composition, not seen in this experiment because of the similarity of the plant communities.

  13. Grassland Arthropods Are Controlled by Direct and Indirect Interactions with Cattle but Are Largely Unaffected by Plant Provenance.

    Directory of Open Access Journals (Sweden)

    Kelly Anne Farrell

    Full Text Available Cattle grazing and invasion by non-native plant species are globally-ubiquitous changes occurring to plant communities that are likely to reverberate through whole food webs. We used a manipulative field experiment to quantify how arthropod community structure differed in native and non-native California grassland communities in the presence and absence of grazing. The arthropod community was strongly affected by cattle grazing: the biovolume of herbivorous arthropods was 79% higher in grazed than ungrazed plots, whereas the biovolume of predatory arthropods was 13% higher in ungrazed plots. In plots where non-native grasses were grazed, arthropod biovolume increased, possibly in response to increased plant productivity or increased nutritional quality of rapidly-growing annual plants. Grazing may thus affect plant biomass both through the direct removal of biomass, and through arthropod-mediated impacts. We also expected the arthropod community to differ between native and non-native plant communities; surprisingly, arthropod richness and diversity did not vary consistently between these grass community types, although arthropod abundance was slightly higher in plots with native and ungrazed grasses. These results suggest that whereas cattle grazing affects the arthropod community via direct and indirect pathways, arthropod community changes commonly associated with non-native plant invasions may not be due to the identity or dominance of the invasive species in those systems, but to accompanying changes in plant traits or functional group composition, not seen in this experiment because of the similarity of the plant communities.

  14. Sesquiterpene lactones and monoterpene glucosides from plant species Picris echoides

    Directory of Open Access Journals (Sweden)

    MILUTIN STEFANOVIC

    2000-11-01

    Full Text Available Investigation of the constituents of the aerial parts of domestic plant species Picris echoides afforded the sesquiterpene lactones, i.e., guaianolides jacquilenin (1, 11-epi-jacquilenin (2, achillin (3 and eudesmanolide telekin (4. The chemical indentification of the two monoterpene glucosides (–-cis-chrysanthenol-b-D-glucopyranoside (5 and its 6’-acetate 6 is also repoted. The guaianolide achillin (3 and the two monoterpene glucosides 5 and 6 were isolated for the first time from this plant species. Isolation was achieved by column chromatography and the structures were established mainly by the interpretation of their physical and spectral data, which were in agreement with those in the literature.

  15. Hydroperiod regime controls the organization of plant species in wetlands

    OpenAIRE

    Foti, R.; del Jesus, M.; Rinaldo, A.; Rodriguez-Iturbe, I.

    2012-01-01

    With urban, agricultural, and industrial needs growing throughout the past decades, wetland ecosystems have experienced profound changes. Most critically, the biodiversity of wetlands is intimately linked to its hydrologic dynamics, which in turn are being drastically altered by ongoing climate changes. Hydroperiod regimes, e.g., percentage of time a site is inundated, exert critical control in the creation of niches for different plant species in wetlands. However, the spatial signatures of ...

  16. The Phytotoxicity of Designated Pollutants on Plant Species

    Science.gov (United States)

    1984-03-01

    Only seeds collected from those flowers exposed during pollin 20. DISTRIBUTION/AVAILABILITY OF ABSTRACT 21. ABSTRACT SECURITY CLASSIFICATION...acid exposure during pollination lowered the germination rate of mature seeds. Plant injury was chiefly a function of acid concentration, but amount...TESTS Species Name Variety Barley Hordeum vulgare L. CM67 Bean Phaseolus vulgaris L. Pinto Citrus Citrus limon (L.) Lupe Lemon Lettuce Lactuca sativa

  17. Evaluating Hypotheses of Plant Species Invasions on Mediterranean Islands: Inverse Patterns between Alien and Endemic Species

    Directory of Open Access Journals (Sweden)

    Alexander Bjarnason

    2017-08-01

    Full Text Available Invasive alien species cause major changes to ecosystem functioning and patterns of biodiversity, and the main factors involved in invasion success remain contested. Using the Mediterranean island of Crete, Greece as a case study, we suggest a framework for analyzing spatial data of alien species distributions, based on environmental predictors, aiming to gain an understanding of their spatial patterns and spread. Mediterranean islands are under strong ecological pressure from invading species due to their restricted size and increased human impact. Four hypotheses of invasibility, the “propagule pressure hypothesis” (H1, “biotic resistance hypothesis vs. acceptance hypothesis” (H2, “disturbance-mediated hypothesis” (H3, and “environmental heterogeneity hypothesis” (H4 were tested. Using data from alien, native, and endemic vascular plant species, the propagule pressure, biotic resistance vs. acceptance, disturbance-mediated, and environmental heterogeneity hypotheses were tested with Generalized Additive Modeling (GAM of 39 models. Based on model selection, the optimal model includes the positive covariates of native species richness, the negative covariates of endemic species richness, and land area. Variance partitioning between the four hypotheses indicated that the biotic resistance vs. acceptance hypothesis explained the vast majority of the total variance. These results show that areas of high species richness have greater invasibility and support the acceptance hypothesis and “rich-get-richer” distribution of alien species. The negative correlation between alien and endemic species appears to be predominantly driven by altitude, with fewer alien and more endemic species at greater altitudes, and habitat richness. The negative relationship between alien and endemic species richness provides potential for understanding patterns of endemic and alien species on islands, contributing to more effective conservation

  18. Floristic characteristics of alien invasive seed plant species in China.

    Science.gov (United States)

    Wang, Congyan; Liu, Jun; Xiao, Hongguang; Zhou, Jiawei; DU, Daolin

    2016-01-01

    This study aims to determine the floristic characteristics of alien invasive seed plant species (AISPS) in China. There are a total of five hundred and thirteen AISPS, belonging to seventy families and two hundred and eighty-three genera. Seventy families were classified into nine areal types at the family level, and "Cosmopolitan" and "Pantropic" are the two main types. Two hundred and eighty-three genera were classified into twelve areal types at the genus level, and "Pantropic", "Trop. Asia & Amer. disjuncted", and "Cosmopolitan" are the three main types. These results reveal a certain degree of diversity among AISPS in China. The floristic characteristics at the family level exhibit strong pantropic characteristics. Two possible reasons for this are as follows. Firstly, southeastern China is heavily invaded by alien invasive plant species and this region has a mild climate. Secondly, southeastern China is more disturbed by human activities than other regions in China. The floristic characteristics at the genus level display strong pantropic but with abundant temperate characteristics. This may be due to that China across five climatic zones and the ecosystems in which the most alien invasive plant species occur have the same or similar climate with their natural habitat.

  19. Biodegradation of 2,4-dinitrotoluene by different plant species.

    Science.gov (United States)

    Podlipná, Radka; Pospíšilová, Blanka; Vaněk, Tomáš

    2015-02-01

    Over the past century, rapid growth of population, mining and industrialization significantly contributed to extensive soil, air and water contamination. The 2,4-dinitrotoluene (2,4-DNT), used mostly as explosive, belongs to the hazardous xenobiotics. Soils and waters contaminated with 2,4-DNT may be cleaned by phytoremediation using suitable plant species. The ability of crop plants (hemp, flax, sunflower and mustard) to germinate and grow on soils contaminated with 2,4-DNT was compared. Stimulation of their growth was found at 0.252 mg/g 2,4-DNT. The lethal concentration for the growth for these species was around 1 mg/g. In hydropony, the above mentioned species were able to survive 200 mg/l 2,4-DNT, the concentration close to maximal solubility of 2,4-DNT in water. Metabolism of 2,4-DNT was tested using suspension culture of soapwort and reed. The degradation products 2-aminonitrotoluene and 4-aminonitrotoluene were found both in the medium and in the acetone extract of plant cells. The test showed that the toxicity of these metabolites was higher than the toxicity of the parent compound, but 2,4-diaminotoluene, the product of next reduction step, was less toxic in the concentration range tested (0-200 mg/l). Copyright © 2014. Published by Elsevier Inc.

  20. Are litter decomposition and fire linked through plant species traits?

    Science.gov (United States)

    Cornelissen, Johannes H C; Grootemaat, Saskia; Verheijen, Lieneke M; Cornwell, William K; van Bodegom, Peter M; van der Wal, René; Aerts, Rien

    2017-11-01

    Contents 653 I. 654 II. 657 III. 659 IV. 661 V. 662 VI. 663 VII. 665 665 References 665 SUMMARY: Biological decomposition and wildfire are connected carbon release pathways for dead plant material: slower litter decomposition leads to fuel accumulation. Are decomposition and surface fires also connected through plant community composition, via the species' traits? Our central concept involves two axes of trait variation related to decomposition and fire. The 'plant economics spectrum' (PES) links biochemistry traits to the litter decomposability of different fine organs. The 'size and shape spectrum' (SSS) includes litter particle size and shape and their consequent effect on fuel bed structure, ventilation and flammability. Our literature synthesis revealed that PES-driven decomposability is largely decoupled from predominantly SSS-driven surface litter flammability across species; this finding needs empirical testing in various environmental settings. Under certain conditions, carbon release will be dominated by decomposition, while under other conditions litter fuel will accumulate and fire may dominate carbon release. Ecosystem-level feedbacks between decomposition and fire, for example via litter amounts, litter decomposition stage, community-level biotic interactions and altered environment, will influence the trait-driven effects on decomposition and fire. Yet, our conceptual framework, explicitly comparing the effects of two plant trait spectra on litter decomposition vs fire, provides a promising new research direction for better understanding and predicting Earth surface carbon dynamics. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  1. Unmanned Aerial Vehicles for Alien Plant Species Detection and Monitoring

    Science.gov (United States)

    Dvořák, P.; Müllerová, J.; Bartaloš, T.; Brůna, J.

    2015-08-01

    Invasive species spread rapidly and their eradication is difficult. New methods enabling fast and efficient monitoring are urgently needed for their successful control. Remote sensing can improve early detection of invading plants and make their management more efficient and less expensive. In an ongoing project in the Czech Republic, we aim at developing innovative methods of mapping invasive plant species (semi-automatic detection algorithms) by using purposely designed unmanned aircraft (UAV). We examine possibilities for detection of two tree and two herb invasive species. Our aim is to establish fast, repeatable and efficient computer-assisted method of timely monitoring, reducing the costs of extensive field campaigns. For finding the best detection algorithm we test various classification approaches (object-, pixel-based and hybrid). Thanks to its flexibility and low cost, UAV enables assessing the effect of phenological stage and spatial resolution, and is most suitable for monitoring the efficiency of eradication efforts. However, several challenges exist in UAV application, such as geometrical and radiometric distortions, high amount of data to be processed and legal constrains for the UAV flight missions over urban areas (often highly invaded). The newly proposed UAV approach shall serve invasive species researchers, management practitioners and policy makers.

  2. ANTIFUNGAL POTENTIAL OF PLANT SPECIES FROM BRAZILIAN CAATINGA AGAINST DERMATOPHYTES.

    Science.gov (United States)

    Biasi-Garbin, Renata Perugini; Demitto, Fernanda de Oliveira; Amaral, Renata Claro Ribeiro do; Ferreira, Magda Rhayanny Assunção; Soares, Luiz Alberto Lira; Svidzinski, Terezinha Inez Estivalet; Baeza, Lilian Cristiane; Yamada-Ogatta, Sueli Fumie

    2016-01-01

    Trichophyton rubrum and Trichophyton mentagrophytes complex, or Trichophyton spp. are the main etiologic agents of dermatophytosis, whose treatment is limited by the high cost of antifungal treatments, their various side effects, and the emergence of resistance amongst these species. This study evaluated the in vitro antidermatophytic activity of 23 crude extracts from nine plant species of semiarid vegetation (caatinga) found in Brazil. The extracts were tested at concentrations ranging from 1.95 to 1,000.0 mg/mL by broth microdilution assay against the reference strains T. rubrum ATCC 28189 and T. mentagrophytes ATCC 11481, and 33 clinical isolates of dermatophytes. All plants showed a fungicidal effect against both fungal species, with MIC/MFC values of the active extracts ranging from 15.6 to 250.0 µg/mL. Selected extracts of Eugenia uniflora (AcE), Libidibia ferrea (AE), and Persea americana (AcE) also exhibited a fungicidal effect against all clinical isolates of T. rubrum and T. mentagrophytes complex. This is the first report of the antifungal activity of Schinus terebinthifolius, Piptadenia colubrina, Parapiptadenia rigida, Mimosa ophthalmocentra, and Persea americana against both dermatophyte species.

  3. ANTIFUNGAL POTENTIAL OF PLANT SPECIES FROM BRAZILIAN CAATINGA AGAINST DERMATOPHYTES

    Science.gov (United States)

    BIASI-GARBIN, Renata Perugini; DEMITTO, Fernanda de Oliveira; do AMARAL, Renata Claro Ribeiro; FERREIRA, Magda Rhayanny Assunção; SOARES, Luiz Alberto Lira; SVIDZINSKI, Terezinha Inez Estivalet; BAEZA, Lilian Cristiane; YAMADA-OGATTA, Sueli Fumie

    2016-01-01

    Trichophyton rubrum and Trichophyton mentagrophytes complex, or Trichophyton spp. are the main etiologic agents of dermatophytosis, whose treatment is limited by the high cost of antifungal treatments, their various side effects, and the emergence of resistance amongst these species. This study evaluated the in vitro antidermatophytic activity of 23 crude extracts from nine plant species of semiarid vegetation (caatinga) found in Brazil. The extracts were tested at concentrations ranging from 1.95 to 1,000.0 mg/mL by broth microdilution assay against the reference strains T. rubrum ATCC 28189 and T. mentagrophytesATCC 11481, and 33 clinical isolates of dermatophytes. All plants showed a fungicidal effect against both fungal species, with MIC/MFC values of the active extracts ranging from 15.6 to 250.0 µg/mL. Selected extracts of Eugenia uniflora (AcE), Libidibia ferrea (AE), and Persea americana (AcE) also exhibited a fungicidal effect against all clinical isolates of T. rubrum and T. mentagrophytes complex. This is the first report of the antifungal activity of Schinus terebinthifolius, Piptadenia colubrina, Parapiptadenia rigida, Mimosa ophthalmocentra, and Persea americana against both dermatophyte species. PMID:27007561

  4. ANTIFUNGAL POTENTIAL OF PLANT SPECIES FROM BRAZILIAN CAATINGA AGAINST DERMATOPHYTES

    Directory of Open Access Journals (Sweden)

    Renata Perugini BIASI-GARBIN

    2016-01-01

    Full Text Available Trichophyton rubrum and Trichophyton mentagrophytes complex, or Trichophyton spp. are the main etiologic agents of dermatophytosis, whose treatment is limited by the high cost of antifungal treatments, their various side effects, and the emergence of resistance amongst these species. This study evaluated the in vitro antidermatophytic activity of 23 crude extracts from nine plant species of semiarid vegetation (caatinga found in Brazil. The extracts were tested at concentrations ranging from 1.95 to 1,000.0 mg/mL by broth microdilution assay against the reference strains T. rubrum ATCC 28189 and T. mentagrophytesATCC 11481, and 33 clinical isolates of dermatophytes. All plants showed a fungicidal effect against both fungal species, with MIC/MFC values of the active extracts ranging from 15.6 to 250.0 µg/mL. Selected extracts of Eugenia uniflora (AcE, Libidibia ferrea (AE, and Persea americana (AcE also exhibited a fungicidal effect against all clinical isolates of T. rubrum and T. mentagrophytes complex. This is the first report of the antifungal activity of Schinus terebinthifolius, Piptadenia colubrina, Parapiptadenia rigida, Mimosa ophthalmocentra, and Persea americana against both dermatophyte species.

  5. Small mammals as indicators of cryptic plant species diversity in the central Chilean plant endemicity hotspot

    Directory of Open Access Journals (Sweden)

    Meredith Root-Bernstein

    2014-12-01

    Full Text Available Indicator species could help to compensate for a shortfall of knowledge about the diversity and distributions of undersampled and cryptic species. This paper provides background knowledge about the ecological interactions that affect and are affected by herbaceous diversity in central Chile, as part of the indicator species selection process. We focus on the ecosystem engineering role of small mammals, primarily the degu Octodon degus. We also consider the interacting effects of shrubs, trees, avian activity, livestock, slope, and soil quality on herbaceous communities in central Chile. We sampled herbaceous diversity on a private landholding characterized by a mosaic of savanna, grassland and matorral, across a range of degu disturbance intensities. We find that the strongest factors affecting endemic herbaceous diversity are density of degu runways, shrub cover and avian activity. Our results show that the degu, a charismatic and easily identifiable and countable species, could be used as an indicator species to aid potential conservation actions such as private protected area uptake. We map areas in central Chile where degus may indicate endemic plant diversity. This area is larger than expected, and suggests that significant areas of endemic plant communities may still exist, and should be identified and protected. Keywords: Cryptic species, Diversity, Endemic, Indicator species, Octodon degus, Plant

  6. History of nonnative Monk Parakeets in Mexico.

    Science.gov (United States)

    Hobson, Elizabeth A; Smith-Vidaurre, Grace; Salinas-Melgoza, Alejandro

    2017-01-01

    Nonnative Monk Parakeets have been reported in increasing numbers across many cities in Mexico, and were formally classified as an invasive species in Mexico in late 2016. However, there has not been a large-scale attempt to determine how international pet trade and national and international governmental regulations have played a part in colonization, and when the species appeared in different areas. We describe the changes in regulations that led the international pet trade market to shift to Mexico, then used international trade data to determine how many parakeets were commercially imported each year and where those individuals originated. We also quantified the recent increases in Monk Parakeet (Myiopsitta monachus) sightings in Mexico in both the scientific literature and in citizen science reports. We describe the timeline of increased reports to understand the history of nonnative Monk Parakeets in Mexico. As in other areas where the species has colonized, the main mode of transport is through the international pet trade. Over half a million Monk Parakeets were commercially imported to Mexico during 2000-2015, with the majority of importation (90%) occurring in 2008-2014, and almost all (98%) were imported from Uruguay. The earliest record of a free-flying Monk Parakeet was observed during 1994-1995 in Mexico City, but sightings of the parakeets did not become geographically widespread in either the scientific literature or citizen science databases until 2012-2015. By 2015, parakeets had been reported in 97 cities in Mexico. Mexico City has consistently seen steep increases in reporting since this species was first reported in Mexico. Here we find that both national and international legal regulations and health concerns drove a rise and fall in Monk Parakeet pet trade importations, shortly followed by widespread sightings of feral parakeets across Mexico. Further monitoring of introduced Monk Parakeet populations in Mexico is needed to understand the

  7. Interspecific competition of early successional plant species in ex-arable fields as influenced by plant-soil feedback

    OpenAIRE

    Jing, Jingying; Bezemer, T. Martijn; Van der Putten, Wim H.

    2015-01-01

    Plant–soil feedback can affect plants that belong to the same (intraspecific feedback) or different species (interspecific feedback). However, little is known about how intra- and interspecific plant–soil feedbacks influence interspecific plant competition. Here, we used plants and soil from early-stage ex-arable fields to examine how intra- and interspecific plant–soil feedbacks affect the performance of 10 conditioning species and the focal species, Jacobaea vulgaris. Plants were grown alon...

  8. [Psychoactive plant species--actual list of plants prohibited in Poland].

    Science.gov (United States)

    Simonienko, Katarzyna; Waszkiewicz, Napoleon; Szulc, Agata

    2013-01-01

    According to the Act on Counteracting Drug Addiction (20-th of March, 2009, Dz. U. Nr 63 poz. 520.) the list of federally prohibited plants in Poland was expanded to include 16 new species. Until that time the only illegal plant materials were cannabis, papaver, coca and most of their products. The actual list of herbal narcotics includes species which significantly influence on the central nervous system work but which are rarely described in the national literature. The plants usually come from distant places, where--among primeval cultures--are used for ritual purposes. In our civilization the plants are usually used experimentally, recreationally or to gain particular narcotic effects. The results of the consumption vary: they can be specific or less typical, imitate other substances intake, mental disorders or different pathological states. The plant active substances can interact with other medicaments, be toxic to internal organs, cause serious threat to health or even death. This article describes the sixteen plant species, which are now prohibited in Poland, their biochemical ingredients and their influence on the human organism.

  9. Challenging the view that invasive non-native plants are not a significant threat to the floristic diversity of Great Britain

    Czech Academy of Sciences Publication Activity Database

    Hulme, P. E.; Pauchard, A.; Pyšek, Petr; Vila, M.; Alba, Christina; Blackburn, T. M.; Bullock, J. M.; Chytrý, M.; Dawson, W.; Dunn, A. M.; Essl, F.; Genovesi, P.; Maskell, L. C.; Meyerson, L. A.; Nunez, M. A.; Pergl, Jan; Pescott, O. L.; Pocock, M. J. O.; Richardson, D. M.; Roy, H. E.; Smart, S. M.; Štajerová, Kateřina; Stohlgren, T.; van Kleunen, M.; Winter, M.

    2015-01-01

    Roč. 112, č. 23 (2015), E2988-E2989 ISSN 0027-8424 Institutional support: RVO:67985939 Keywords : plant invasions * impact * misleading analyse Subject RIV: EH - Ecology, Behaviour Impact factor: 9.423, year: 2015

  10. Invasive plant species: Inventory, mapping, and monitoring - A national strategy

    Science.gov (United States)

    Ludke, J. Larry; D'Erchia, Frank; Coffelt, Jan; Hanson, Leanne

    2002-01-01

    America is under siege by invasive species of plants and animals, and by diseases. The current environmental, economic, and health-related costs of invasive species could exceed $138 billion per year-more than all other natural disasters combined. Notorious examples include West Nile virus, Dutch elm disease, chestnut blight, and purple loose- strife in the Northeast; kudzu, Brazilian peppertree, water hyacinth, nutria, and fire ants in the Southeast; zebra mussels, leafy spurge, and Asian long-horn beetles in the Midwest; salt cedar, Russian olive, and Africanized bees in the Southwest; yellow star thistle, European wild oats, oak wilt disease, Asian clams, and white pine blister rust in California; cheatgrass, various knapweeds, and thistles in the Great Basin; whirling disease of salmonids in the Northwest; hundreds of invasive species from microbes to mammals in Hawaii; and the brown tree snake in Guam. Thousands of species from other countries are introduced intentionally or accidentally into the United States each year. Based on past experience, 10-15 percent can be expected to establish free-living populations and about 1 percent can be expected to cause significant impacts to ecosystems, native species, economic productivity, and (or) human health.

  11. Plant Size as Determinant of Species Richness of Herbivores, Natural Enemies and Pollinators across 21 Brassicaceae Species.

    Directory of Open Access Journals (Sweden)

    Hella Schlinkert

    Full Text Available Large plants are often more conspicuous and more attractive for associated animals than small plants, e.g. due to their wider range of resources. Therefore, plant size can positively affect species richness of associated animals, as shown for single groups of herbivores, but studies usually consider intraspecific size differences of plants in unstandardised environments. As comprehensive tests of interspecific plant size differences under standardised conditions are missing so far, we investigated effects of plant size on species richness of all associated arthropods using a common garden experiment with 21 Brassicaceae species covering a broad interspecific plant size gradient from 10 to 130 cm height. We recorded plant associated ecto- and endophagous herbivores, their natural enemies and pollinators on and in each aboveground plant organ, i.e. flowers, fruits, leaves and stems. Plant size (measured as height from the ground, the number of different plant organ entities and their biomass were assessed. Increasing plant size led to increased species richness of associated herbivores, natural enemies and pollinating insects. This pattern was found for ectophagous and endophagous herbivores, their natural enemies, as well as for herbivores associated with leaves and fruits and their natural enemies, independently of the additional positive effects of resource availability (i.e. organ biomass or number of entities and, regarding natural enemies, herbivore species richness. We found a lower R2 for pollinators compared to herbivores and natural enemies, probably caused by the high importance of flower characteristics for pollinator species richness besides plant size. Overall, the increase in plant height from 10 to 130 cm led to a 2.7-fold increase in predicted total arthropod species richness. In conclusion, plant size is a comprehensive driver of species richness of the plant associated arthropods, including pollinators, herbivores and their

  12. Effects of 'target' plant species body size on neighbourhood species richness and composition in old-field vegetation.

    Directory of Open Access Journals (Sweden)

    Brandon S Schamp

    Full Text Available Competition is generally regarded as an important force in organizing the structure of vegetation, and evidence from several experimental studies of species mixtures suggests that larger mature plant size elicits a competitive advantage. However, these findings are at odds with the fact that large and small plant species generally coexist, and relatively smaller species are more common in virtually all plant communities. Here, we use replicates of ten relatively large old-field plant species to explore the competitive impact of target individual size on their surrounding neighbourhoods compared to nearby neighbourhoods of the same size that are not centred by a large target individual. While target individuals of the largest of our test species, Centaurea jacea L., had a strong impact on neighbouring species, in general, target species size was a weak predictor of the number of other resident species growing within its immediate neighbourhood, as well as the number of resident species that were reproductive. Thus, the presence of a large competitor did not restrict the ability of neighbouring species to reproduce. Lastly, target species size did not have any impact on the species size structure of neighbouring species; i.e. they did not restrict smaller, supposedly poorer competitors, from growing and reproducing close by. Taken together, these results provide no support for a size-advantage in competition restricting local species richness or the ability of small species to coexist and successfully reproduce in the immediate neighbourhood of a large species.

  13. Snowpack, fire, and forest disturbance: interactions affect montane invasions by non-native shrubs.

    Science.gov (United States)

    Stevens, Jens T; Latimer, Andrew M

    2015-06-01

    Montane regions worldwide have experienced relatively low plant invasion rates, a trend attributed to increased climatic severity, low rates of disturbance, and reduced propagule pressure relative to lowlands. Manipulative experiments at elevations above the invasive range of non-native species can clarify the relative contributions of these mechanisms to montane invasion resistance, yet such experiments are rare. Furthermore, global climate change and land use changes are expected to cause decreases in snowpack and increases in disturbance by fire and forest thinning in montane forests. We examined the importance of these factors in limiting montane invasions using a field transplant experiment above the invasive range of two non-native lowland shrubs, Scotch broom (Cytisus scoparius) and Spanish broom (Spartium junceum), in the rain-snow transition zone of the Sierra Nevada of California. We tested the effects of canopy closure, prescribed fire, and winter snow depth on demographic transitions of each species. Establishment of both species was most likely at intermediate levels of canopy disturbance, but at this intermediate canopy level, snow depth had negative effects on winter survival of seedlings. We used matrix population models to show that an 86% reduction in winter snowfall would cause a 2.8-fold increase in population growth rates in Scotch broom and a 3.5-fold increase in Spanish broom. Fall prescribed fire increased germination rates, but decreased overall population growth rates by reducing plant survival. However, at longer fire return intervals, population recovery between fires is likely to keep growth rates high, especially under low snowpack conditions. Many treatment combinations had positive growth rates despite being above the current invasive range, indicating that propagule pressure, disturbance, and climate can all strongly affect plant invasions in montane regions. We conclude that projected reductions in winter snowpack and increases in

  14. Hydroperiod regime controls the organization of plant species in wetlands.

    Science.gov (United States)

    Foti, Romano; del Jesus, Manuel; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio

    2012-11-27

    With urban, agricultural, and industrial needs growing throughout the past decades, wetland ecosystems have experienced profound changes. Most critically, the biodiversity of wetlands is intimately linked to its hydrologic dynamics, which in turn are being drastically altered by ongoing climate changes. Hydroperiod regimes, e.g., percentage of time a site is inundated, exert critical control in the creation of niches for different plant species in wetlands. However, the spatial signatures of the organization of plant species in wetlands and how the different drivers interact to yield such signatures are unknown. Focusing on Everglades National Park (ENP) in Florida, we show here that cluster sizes of each species follow a power law probability distribution and that such clusters have well-defined fractal characteristics. Moreover, we individuate and model those signatures via the interplay between global forcings arising from the hydroperiod regime and local controls exerted by neighboring vegetation. With power law clustering often associated with systems near critical transitions, our findings are highly relevant for the management of wetland ecosystems. In addition, our results show that changes in climate and land management have a quantifiable predictable impact on the type of vegetation and its spatial organization in wetlands.

  15. REMOTE DETENTION OF INVASIVE AND OPPORTUNISTIC PLANT SPECIES IN GREAT LAKES COASTAL WETLANDS

    Science.gov (United States)

    Invasive and opportunistic plant species have been associated with wetland disturbance. Increases in the abundance of plant species such as common reed (Phragmites australis) in coastal Great Lakes wetlands are hypothesized to occur with shifts toward drier hydrologic regimes, fr...

  16. Plant-associated bacterial populations on native and invasive plant species: comparisons between 2 freshwater environments.

    Science.gov (United States)

    Olapade, Ola A; Pung, Kayleigh

    2012-06-01

    Plant-microbial interactions have been well studied because of the ecological importance of such relationships in aquatic systems. However, general knowledge regarding the composition of these biofilm communities is still evolving, partly as a result of several confounding factors that are attributable to plant host properties and to hydrodynamic conditions in aquatic environments. In this study, the occurrences of various bacterial phylogenetic taxa on 2 native plants, i.e., mayapple (Podophyllum peltatum L.) and cow parsnip (Heracleum maximum Bartram), and on an invasive species, i.e., garlic mustard (Alliaria petiolata (M. Bieb.) Cavara & Grande), were quantitatively examined using nucleic acid staining and fluorescence in situ hybridization. The plants were incubated in triplicates for about a week within the Kalamazoo River and Pierce Cedar Creek as well as in microcosms. The bacterial groups targeted for enumeration are known to globally occur in relatively high abundance and are also ubiquitously distributed in freshwater environments. Fluorescence in situ hybridization analyses of the bacterioplankton assemblages revealed that the majority of bacterial cells that hybridized with the different probes were similar between the 2 sites. In contrast, the plant-associated populations while similar on the 3 plants incubated in Kalamazoo River, their representations were highest on the 2 native plants relative to the invasive species in Pierce Cedar Creek. Overall, our results further suggested that epiphytic bacterial assemblages are probably under the influences of and probably subsequently respond to multiple variables and conditions in aquatic milieus.

  17. Plant cell walls: New insights from ancient species

    DEFF Research Database (Denmark)

    Sørensen, Iben; Willats, William George Tycho

    2008-01-01

    Cell walls are a defining feature of plants and have numerous crucial roles in growth and development. They are also the largest source of terrestrial biomass and have many important industrial applications - ranging from bulk products to functional food ingredients. There is considerable interest......¿4)-linked ß-D-Glcp are joined by occasional (1¿3)-linkages. This mixed linkage glucan (MLG) has been the subject of extensive research because of the economic importance of several Poales species including rice, barley and wheat and because MLG has proven health benefits. The recent discovery of MLG...

  18. 45 CFR 670.25 - Designation of specially protected species of native mammals, birds, and plants.

    Science.gov (United States)

    2010-10-01

    ... native mammals, birds, and plants. 670.25 Section 670.25 Public Welfare Regulations Relating to Public... Protected Species of Mammals, Birds, and Plants § 670.25 Designation of specially protected species of native mammals, birds, and plants. The following species has been designated as Specially Protected...

  19. 7 CFR 650.22 - Rare, threatened, and endangered species of plants and animals.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Rare, threatened, and endangered species of plants and... Related Environmental Concerns § 650.22 Rare, threatened, and endangered species of plants and animals. (a) Background. (1) A variety of plant and animal species of the United States are so reduced in numbers that...

  20. Monitoring the effects of atmospheric ethylene near polyethylene manufacturing plants with two sensitive plant species

    International Nuclear Information System (INIS)

    Tonneijck, A.E.G.; Berge, W.F. ten; Jansen, B.P.

    2003-01-01

    Atmospheric ethylene from polyethylene manufacturing plants adversely affected the number of flowers and growth of field-grown marigold and petunia. - Data of a multi-year (1977-1983) biomonitoring programme with marigold and petunia around polyethylene manufacturing plants was analysed to assess plant responses to atmospheric ethylene and to determine the area at risk for the phytotoxic effects of this pollutant. In both species, flower formation and growth were severely reduced close to the emission sources and plant performance improved with increasing distance. Plants exposed near the border of the research area had more flowers than the unexposed control while their growth was normal. Measurements of ethylene concentrations at a border site revealed that the growing season mean was 61.5 μg m -3 in 1982 and 15.6 μg m -3 in 1983. In terms of number of flowers, petunia was more sensitive than marigold and adverse effects were observed within ca. 400 m distance from the sources for marigold and within ca. 460 m for petunia. The area at risk (ca. 870 m) for ethylene-induced growth reduction was also limited to the industrial zone. Plants were more sensitive to ethylene in terms of growth reduction than in terms of inhibition of flowering. In the Netherlands, maximum permissible levels of ethylene are currently based on information from laboratory and greenhouse studies. Our results indicate that these levels are rather conservative in protecting field-grown plants against ethylene-induced injury near polyethylene manufacturing plants

  1. Does resource availability, resource heterogeneity or species turnover mediate changes in plant species richness in grazed grasslands?

    NARCIS (Netherlands)

    Bakker, C; Blair, JM; Knapp, AK

    2003-01-01

    Grazing by large ungulates often increases plant species richness in grasslands of moderate to high productivity. In a mesic North American grassland with and without the presence of bison (Bos bison), a native ungulate grazer, three non-exclusive hypotheses for increased plant species richness in

  2. 78 FR 48943 - Endangered and Threatened Wildlife and Plants; Endangered Species Act Listing Determination for...

    Science.gov (United States)

    2013-08-12

    ... Atmospheric Administration Endangered and Threatened Wildlife and Plants; Endangered Species Act Listing...; Endangered Species Act Listing Determination for Alewife and Blueback Herring AGENCY: National Marine... (Alosa aestivalis) as threatened under the Endangered Species Act (ESA) throughout all or a significant...

  3. Positive effects of plant species diversity on productivity in the absence of legumes

    NARCIS (Netherlands)

    Ruijven, van J.; Berendse, F.

    2003-01-01

    We investigated the effect of species richness on productivity in randomly assembled grassland communities without legumes. Aboveground biomass increased with increasing species richness and different measures of complementarity showed strong increases with plant species richness. Increasing

  4. Differences in dry weight partitioning and flowering phenology between native and non-native plants of purple loosestrife (Lythrum salicaria L.)

    Czech Academy of Sciences Publication Activity Database

    Bastlová, D.; Květ, Jan

    2002-01-01

    Roč. 197, - (2002), s. 332-340 ISSN 0367-2530 R&D Projects: GA ČR GA206/00/1113; GA MŠk OU94035; GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z6005908; CEZ:MSM 123100004 Keywords : plant invasions * Eurasia * North America Subject RIV: EF - Botanics Impact factor: 1.132, year: 2002

  5. Effect of plant species on nitrogen recovery in aquaponics.

    Science.gov (United States)

    Hu, Zhen; Lee, Jae Woo; Chandran, Kartik; Kim, Sungpyo; Brotto, Ariane Coelho; Khanal, Samir Kumar

    2015-01-01

    Nitrogen transformations in aquaponics with different edible plant species, i.e., tomato (Lycopersicon esculentum) and pak choi (Brassica campestris L. subsp. chinensis) were systematically examined and compared. Results showed that nitrogen utilization efficiencies (NUE) of tomato- and pak choi-based aquaponic systems were 41.3% and 34.4%, respectively. The abundance of nitrifying bacteria in tomato-based aquaponics was 4.2-folds higher than that in pak choi-based aquaponics, primarily due to its higher root surface area. In addition, tomato-based aquaponics had better water quality than that of pak choi-based aquaponics. About 1.5-1.9% of nitrogen input were emitted to atmosphere as nitrous oxide (N2O) in tomato- and pak choi-based aquaponic systems, respectively, suggesting that aquaponics is a potential anthropogenic source of N2O emission. Overall, this is the first intensive study that examined the role plant species played in aquaponics, which could provide new strategy in designing and operating an aquaponic system. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Discriminant WSRC for Large-Scale Plant Species Recognition

    Directory of Open Access Journals (Sweden)

    Shanwen Zhang

    2017-01-01

    Full Text Available In sparse representation based classification (SRC and weighted SRC (WSRC, it is time-consuming to solve the global sparse representation problem. A discriminant WSRC (DWSRC is proposed for large-scale plant species recognition, including two stages. Firstly, several subdictionaries are constructed by dividing the dataset into several similar classes, and a subdictionary is chosen by the maximum similarity between the test sample and the typical sample of each similar class. Secondly, the weighted sparse representation of the test image is calculated with respect to the chosen subdictionary, and then the leaf category is assigned through the minimum reconstruction error. Different from the traditional SRC and its improved approaches, we sparsely represent the test sample on a subdictionary whose base elements are the training samples of the selected similar class, instead of using the generic overcomplete dictionary on the entire training samples. Thus, the complexity to solving the sparse representation problem is reduced. Moreover, DWSRC is adapted to newly added leaf species without rebuilding the dictionary. Experimental results on the ICL plant leaf database show that the method has low computational complexity and high recognition rate and can be clearly interpreted.

  7. A management guide for invasive plants in southern forests

    Science.gov (United States)

    James H. Miller; Steven T. Manning; Stephen F. Enloe

    2013-01-01

    Invasions of nonnative plants into forests of the Southern United States continue to spread and include new species, increasingly eroding forest productivity, hindering forest use and management activities, and degrading diversity and wildlife habitat. This book provides the latest information on how to organize and enact prevention programs, build strategies,...

  8. Non-Native (Exotic) Snake Envenomations in the U.S., 2005–2011

    OpenAIRE

    Warrick, Brandon J.; Boyer, Leslie V.; Seifert, Steven A.

    2014-01-01

    Non-native (exotic) snakes are a problematic source of envenomation worldwide. This manuscript describes the current demographics, outcomes and challenges of non-native snakebites in the United States (U.S.). We performed a retrospective case series of the National Poison Data System (NPDS) database between 2005 and 2011. There were 258 human exposures involving at least 61 unique exotic venomous species (average = 37 per year; range = 33–40). Males comprised 79% and females 21%. The averag...

  9. Antifungal Effect of Plant Essential Oils on Controlling Phytophthora Species

    Directory of Open Access Journals (Sweden)

    Jahanshir Amini

    2016-02-01

    Full Text Available In this study, antifungal activity of essential oils of Cymbopogon citratus and Ocimum basilicum and two fungicides Mancozeb and Metalaxyl-Mancozeb in six different concentrations were investigated for controlling three species of Phytophthora, including P. capsici, P. drechsleri and P. melonis on pepper, cucumber and melon under in vitro and greenhouse conditions, respectively. Under the in vitro condition, the median effective concen- tration (EC₅₀ values (ppm of plant essential oils and fungicides were measured. In greenhouse, soil infested with Phytophthora species was treated by adding 50 ml of essential oils and fungicides (100 ppm. Disease severity was determined after 28 days. Among two tested plant essential oils, C. citratus had the lowest EC₅₀ values for inhibition of the mycelial growth of P. capsici (31.473, P. melonis (33.097 and P. drechsleri (69.112, respectively. The mean EC₅₀ values for Metalaxyl-Mancozeb on these pathogens were 20.87, 20.06 and 17.70, respectively. Chemical analysis of plant essential oils by GC-MS showed that, among 42 compounds identified from C. citratus, two compounds β-geranial (α-citral (39.16% and z-citral (30.95% were the most abundant. Under the greenhouse condition, Metalaxyl-Mancozeb caused the greatest reduction in disease severity, 84.2%, 86.8% and 92.1% on melon, cucumber, and pepper, respectively. The C. citratus essential oil reduced disease severity from 47.4% to 60.5% compared to the untreated control (p≤0.05. Essential oils of O. basilicum had the lowest effects on the pathogens under in vitro and greenhouse conditions. These results show that essential oils may contribute to the development of new antifungal agents to protect the crops from Phytophthora diseases.

  10. Reactive oxygen species, essential molecules, during plant-pathogen interactions.

    Science.gov (United States)

    Camejo, Daymi; Guzmán-Cedeño, Ángel; Moreno, Alexander

    2016-06-01

    Reactive oxygen species (ROS) are continually generated as a consequence of the normal metabolism in aerobic organisms. Accumulation and release of ROS into cell take place in response to a wide variety of adverse environmental conditions including salt, temperature, cold stresses and pathogen attack, among others. In plants, peroxidases class III, NADPH oxidase (NOX) locates in cell wall and plasma membrane, respectively, may be mainly enzymatic systems involving ROS generation. It is well documented that ROS play a dual role into cells, acting as important signal transduction molecules and as toxic molecules with strong oxidant power, however some aspects related to its function during plant-pathogen interactions remain unclear. This review focuses on the principal enzymatic systems involving ROS generation addressing the role of ROS as signal molecules during plant-pathogen interactions. We described how the chloroplasts, mitochondria and peroxisomes perceive the external stimuli as pathogen invasion, and trigger resistance response using ROS as signal molecule. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  11. Non-native fishes of the central Indian River Lagoon

    Science.gov (United States)

    Schofield, Pamela J.; Loftus, William F.; Reaver, Kristen M.

    2018-01-01

    We provide a comprehensive review of the status of non-native fishes in the central Indian River Lagoon (from Cape Canaveral to Grant-Valkaria, east of I-95) through literature review and field surveys. Historical records exist for 17 taxa (15 species, one hybrid, one species complex). We found historical records for one additional species, and collected one species in our field survey that had never been recorded in the region before (and which we eradicated). Thus, we evaluate 19 total taxa herein. Of these, we documented range expansion of four salt-tolerant cichlid species, extirpation of six species that were previously recorded from the area and eradication of three species. There was no noticeable change in geographic range for one widespread species and the records for one species are doubtful and may be erroneous. Currently, there is not enough information to evaluate geographic ranges for four species although at least one of those is established.

  12. Number of endemic and native plant species in the Galapagos Archipelago in relation to geographical parameters

    DEFF Research Database (Denmark)

    Willerslev, Eske; Hansen, Anders J.; Nielsen, Kirstine Klitgaard

    2002-01-01

    By simple and multiple regression analyses we investigate updated species numbers of endemic and native vascular plants and seed plants in the Galapagos Archipelago in relation to geographical parameters. We find that the best models to describe species numbers are regression models with log......-transformed species numbers as dependent and log-transformed modified area (i.e. area not covered with barren lava) as an independent variable. This holds both for total species number, for native species number, for endemic species number and for total number of seed plants as well as number of endemic seed plants...

  13. Plant-soil biota interactions and spatial distribution of black cherry in its native and invasive ranges

    NARCIS (Netherlands)

    Reinhart, K.O.; Packer, A.; Van der Putten, W.H.; Clay, K.A.

    2003-01-01

    One explanation for the higher abundance of invasive species in their non-native than native ranges is the escape from natural enemies. But there are few experimental studies comparing the parallel impact of enemies (or competitors and mutualists) on a plant species in its native and invaded ranges,

  14. Novel chemistry of invasive plants: exotic species have more unique metabolomic profiles than native congeners.

    Science.gov (United States)

    Macel, Mirka; de Vos, Ric C H; Jansen, Jeroen J; van der Putten, Wim H; van Dam, Nicole M

    2014-07-01

    It is often assumed that exotic plants can become invasive when they possess novel secondary chemistry compared with native plants in the introduced range. Using untargeted metabolomic fingerprinting, we compared a broad range of metabolites of six successful exotic plant species and their native congeners of the family Asteraceae. Our results showed that plant chemistry is highly species-specific and diverse among both exotic and native species. Nonetheless, the exotic species had on average a higher total number of metabolites and more species-unique metabolites compared with their native congeners. Herbivory led to an overall increase in metabolites in all plant species. Generalist herbivore performance was lower on most of the exotic species compared with the native species. We conclude that high chemical diversity and large phytochemical uniqueness of the exotic species could be indicative of biological invasion potential.

  15. (Non)native Speakered: Rethinking (Non)nativeness and Teacher Identity in TESOL Teacher Education

    Science.gov (United States)

    Aneja, Geeta A.

    2016-01-01

    Despite its imprecision, the native-nonnative dichotomy has become the dominant paradigm for examining language teacher identity development. The nonnative English speaking teacher (NNEST) movement in particular has considered the impact of deficit framings of nonnativeness on "NNEST" preservice teachers. Although these efforts have…

  16. Do native brown trout and non-native brook trout interact reproductively?

    Science.gov (United States)

    Cucherousset, J.; Aymes, J. C.; Poulet, N.; Santoul, F.; Céréghino, R.

    2008-07-01

    Reproductive interactions between native and non-native species of fish have received little attention compared to other types of interactions such as predation or competition for food and habitat. We studied the reproductive interactions between non-native brook trout ( Salvelinus fontinalis) and native brown trout ( Salmo trutta) in a Pyrenees Mountain stream (SW France). We found evidence of significant interspecific interactions owing to consistent spatial and temporal overlap in redd localizations and spawning periods. We observed mixed spawning groups composed of the two species, interspecific subordinate males, and presence of natural hybrids (tiger trout). These reproductive interactions could be detrimental to the reproduction success of both species. Our study shows that non-native species might have detrimental effects on native species via subtle hybridization behavior.

  17. Evaluating nurse plants for restoring native woody species to degraded subtropical woodlands

    Science.gov (United States)

    Yelenik, Stephanie G.; DiManno, Nicole; D’Antonio, Carla M.

    2015-01-01

    Harsh habitats dominated by invasive species are difficult to restore. Invasive grasses in arid environments slow succession toward more desired composition, yet grass removal exacerbates high light and temperature, making the use of “nurse plants” an appealing strategy. In this study of degraded subtropical woodlands dominated by alien grasses in Hawai'i, we evaluated whether individuals of two native (Dodonaea viscosa, Leptocophylla tameiameia) and one non-native (Morella faya) woody species (1) act as natural nodes of recruitment for native woody species and (2) can be used to enhance survivorship of outplanted native woody species. To address these questions, we quantified the presence and persistence of seedlings naturally recruiting beneath adult nurse shrubs and compared survival and growth of experimentally outplanted seedlings of seven native woody species under the nurse species compared to intact and cleared alien-grass plots. We found that the two native nurse shrubs recruit their own offspring, but do not act as establishment nodes for other species. Morella faya recruited even fewer seedlings than native shrubs. Thus, outplanting will be necessary to increase abundance and diversity of native woody species. Outplant survival was the highest under shrubs compared to away from them with few differences between nurse species. The worst habitat for native seedling survival and growth was within the unmanaged invasive grass matrix. Although the two native nurse species did not differentially affect outplant survival, D. viscosa is the most widespread and easily propagated and is thus more likely to be useful as an initial nurse species. The outplanted species showed variable responses to nurse habitats that we attribute to resource requirements resulting from their typical successional stage and nitrogen fixation capability.

  18. Evidence for chemical interference effect of an allelopathic plant on neighboring plant species: A field study.

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    Antonio I Arroyo

    Full Text Available Many studies have reported the phytotoxicity of allelopathic compounds under controlled conditions. However, more field studies are required to provide realistic evidences for the significance of allelopathic interference in natural communities. We conducted a 2-years field experiment in a semiarid plant community (NE Spain. Specifically, we planted juvenile individuals and sowed seeds of Salsola vermiculata L., Lygeum spartum L. and Artemisia herba-alba Asso. (three co-dominant species in the community beneath adult individuals of the allelopathic shrub A. herba-alba, and assessed the growth, vitality, seed germination and seedling survival of those target species with and without the presence of chemical interference by the incorporation of activated carbon (AC to the soil. In addition, juveniles and seeds of the same three target species were planted and sown beneath the canopy of adults of S. vermiculata (a shrub similar to A. herba-alba, but non-allelopathic and in open bare soil to evaluate whether the allelopathic activity of A. herba-alba modulates the net outcome of its interactions with neighboring plants under contrasting abiotic stress conditions. We found that vitality of A. herba-alba juveniles was enhanced beneath A. herba-alba individuals when AC was present. Furthermore, we found that the interaction outcome in A. herba-alba microsite was neutral, whereas a positive outcome was found for S. vermiculata microsite, suggesting that allelopathy may limit the potential facilitative effects of the enhanced microclimatic conditions in A. herba-alba microsite. Yet, L. spartum juveniles were facilitated in A. herba-alba microsite. The interaction outcome in A. herba-alba microsite was positive under conditions of very high abiotic stress, indicating that facilitative interactions predominated over the interference of allelopathic plants under those conditions. These results highlight that laboratory studies can overestimate the

  19. Evidence for chemical interference effect of an allelopathic plant on neighboring plant species: A field study.

    Science.gov (United States)

    Arroyo, Antonio I; Pueyo, Yolanda; Giner, M Luz; Foronda, Ana; Sanchez-Navarrete, Pedro; Saiz, Hugo; Alados, Concepción L

    2018-01-01

    Many studies have reported the phytotoxicity of allelopathic compounds under controlled conditions. However, more field studies are required to provide realistic evidences for the significance of allelopathic interference in natural communities. We conducted a 2-years field experiment in a semiarid plant community (NE Spain). Specifically, we planted juvenile individuals and sowed seeds of Salsola vermiculata L., Lygeum spartum L. and Artemisia herba-alba Asso. (three co-dominant species in the community) beneath adult individuals of the allelopathic shrub A. herba-alba, and assessed the growth, vitality, seed germination and seedling survival of those target species with and without the presence of chemical interference by the incorporation of activated carbon (AC) to the soil. In addition, juveniles and seeds of the same three target species were planted and sown beneath the canopy of adults of S. vermiculata (a shrub similar to A. herba-alba, but non-allelopathic) and in open bare soil to evaluate whether the allelopathic activity of A. herba-alba modulates the net outcome of its interactions with neighboring plants under contrasting abiotic stress conditions. We found that vitality of A. herba-alba juveniles was enhanced beneath A. herba-alba individuals when AC was present. Furthermore, we found that the interaction outcome in A. herba-alba microsite was neutral, whereas a positive outcome was found for S. vermiculata microsite, suggesting that allelopathy may limit the potential facilitative effects of the enhanced microclimatic conditions in A. herba-alba microsite. Yet, L. spartum juveniles were facilitated in A. herba-alba microsite. The interaction outcome in A. herba-alba microsite was positive under conditions of very high abiotic stress, indicating that facilitative interactions predominated over the interference of allelopathic plants under those conditions. These results highlight that laboratory studies can overestimate the significance of

  20. Invasion strategy and abiotic activity triggers for non-native gobiids of the River Rhine.

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    Jan Baer

    Full Text Available The 24 hour activity patterns of three non-native gobiids (round goby Neogobius melanostomus, Western tubenose goby Proterorhinus semilunaris and bighead goby Ponticola kessleri were assessed over 46 consecutive months between 2011 and 2014 from their occurrence in the cooling water intake of a nuclear power plant on the River Rhine, Germany. In total, 117717 gobiids were identified and classified. The occurrence of all three species varied strongly between sampling years, and species-specific activity triggers were identified. The activity of juveniles of all three gobiids species was positively temperature dependent while adult tubenose goby activity appeared to be negatively temperature dependent. Increasing fluvial discharge in the adjoining main river stimulated the activity of juvenile round goby but inhibited activity of adult tubenose goby. Except for adult bighead goby, activity was also structured by time of day, but with no uniform mean. Meteorological factors such as precipitation, air pressure and duration of sunshine hours had little or no influence on gobiid activity. On selected rare occasions, mainly at night, all three species exhibited pulsed swarming behaviour, with thousands of individuals recorded in the intake water. Round goby swarms exhibited both the highest intensity and the largest swarming individuals, suggesting a potential competitive advantage over tubenose and bighead goby. Electric fishing surveys in natural river stretches corroborated this observation. Negative effects on the native fish fauna were apparent only for the bullhead, Cottus gobio. The activity triggers identified offer a unique insight into the invasion mechanisms of these ecosystem-changing non-native gobiids.

  1. Productivity is a poor predictor of plant species richness

    Science.gov (United States)

    Adler, Peter B.; Seabloom, Eric W.; Borer, Elizabeth T.; Hillebrand, Helmut; Hautier, Yann; Hector, Andy; Harpole, W. Stanley; O'Halloran, Lydia R.; Grace, James B.; Anderson, T. Michael; Bakker, Jonathan D.; Biederman, Lori A.; Brown, Cynthia S.; Buckley, Yvonne M.; Calabrese, Laura B.; Chu, Cheng-Jin; Cleland, Elsa E.; Collins, Scott L.; Cottingham, Kathryn L.; Crawley, Michael J.; Damschen, Ellen Ingman; Davies, Kendi F.; DeCrappeo, Nicole M.; Fay, Philip A.; Firn, Jennifer; Frater, Paul; Gasarch, Eve I.; Gruner, Daneil S.; Hagenah, Nicole; Lambers, Janneke Hille Ris; Humphries, Hope; Jin, Virginia L.; Kay, Adam D.; Kirkman, Kevin P.; Klein, Julia A.; Knops, Johannes M.H.; La Pierre, Kimberly J.; Lambrinos, John G.; Li, Wei; MacDougall, Andrew S.; McCulley, Rebecca L.; Melbourne, Brett A.; Mitchell, Charles E.; Moore, Joslin L.; Morgan, John W.; Mortensen, Brent; Orrock, John L.; Prober, Suzanne M.; Pyke, David A.; Risch, Anita C.; Schuetz, Martin; Smith, Melinda D.; Stevens, Carly J.; Sullivan, Lauren L.; Wang, Gang; Wragg, Peter D.; Wright, Justin P.; Yang, Louie H.

    2011-01-01

    For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent meta-analyses questioned the generality of hump-shaped patterns, these syntheses have been criticized for failing to account for methodological differences among studies. We addressed such concerns by conducting standardized sampling in 48 herbaceous-dominated plant communities on five continents. We found no clear relationship between productivity and fine-scale (meters-2) richness within sites, within regions, or across the globe. Ecologists should focus on fresh, mechanistic approaches to understanding the multivariate links between productivity an

  2. Effects of plant diversity on primary production and species interactions in brackish water angiosperm communities

    DEFF Research Database (Denmark)

    Salo, Tiina; Gustafsson, Camilla; Boström, Christoffer

    2009-01-01

    Research on plant biodiversity and ecosystem functioning has mainly focused on terrestrial ecosystems, and our understanding of how plant species diversity and interactions affect processes in marine ecosystems is still limited. To investigate if plant species richness and composition influence...... plant productivity in brackish water angiosperm communities, a 14 wk field experiment was conducted. Using a replacement design with a standardized initial aboveground biomass, shoots of Zostera marina, Potamogeton filiformis and P. perfoliatus were planted on a shallow, sandy bottom in replicated...

  3. Differential responses of soil bacteria, fungi, archaea and protists to plant species richness and plant functional group identity.

    Science.gov (United States)

    Dassen, Sigrid; Cortois, Roeland; Martens, Henk; de Hollander, Mattias; Kowalchuk, George A; van der Putten, Wim H; De Deyn, Gerlinde B

    2017-08-01

    Plants are known to influence belowground microbial community structure along their roots, but the impacts of plant species richness and plant functional group (FG) identity on microbial communities in the bulk soil are still not well understood. Here, we used 454-pyrosequencing to analyse the soil microbial community composition in a long-term biodiversity experiment at Jena, Germany. We examined responses of bacteria, fungi, archaea, and protists to plant species richness (communities varying from 1 to 60 sown species) and plant FG identity (grasses, legumes, small herbs, tall herbs) in bulk soil. We hypothesized that plant species richness and FG identity would alter microbial community composition and have a positive impact on microbial species richness. Plant species richness had a marginal positive effect on the richness of fungi, but we observed no such effect on bacteria, archaea and protists. Plant species richness also did not have a large impact on microbial community composition. Rather, abiotic soil properties partially explained the community composition of bacteria, fungi, arbuscular mycorrhizal fungi (AMF), archaea and protists. Plant FG richness did not impact microbial community composition; however, plant FG identity was more effective. Bacterial richness was highest in legume plots and lowest in small herb plots, and AMF and archaeal community composition in legume plant communities was distinct from that in communities composed of other plant FGs. We conclude that soil microbial community composition in bulk soil is influenced more by changes in plant FG composition and abiotic soil properties, than by changes in plant species richness per se. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  4. Impact of non-native terrestrial mammals on the structure of the terrestrial mammal food web of Newfoundland, Canada.

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    Justin S Strong

    Full Text Available The island of Newfoundland is unique because it has as many non-native terrestrial mammals as native ones. The impacts of non-native species on native flora and fauna can be profound and invasive species have been identified as one of the primary drivers of species extinction. Few studies, however, have investigated the effects of a non-native species assemblage on community and ecosystem properties. We reviewed the literature to build the first terrestrial mammal food web for the island of Newfoundland and then used network analyses to investigate how the timing of introductions and trophic position of non-native species has affected the structure of the terrestrial mammal food web in Newfoundland. The first non-native mammals (house mouse and brown rat became established in Newfoundland with human settlement in the late 15th and early 16th centuries. Coyotes and southern red-backed voles are the most recent mammals to establish themselves on the island in 1985 and 1998, respectively. The fraction of intermediate species increased with the addition of non-native mammals over time whereas the fraction of basal and top species declined over time. This increase in intermediate species mediated by non-native species arrivals led to an overall increase in the terrestrial mammal food web connectance and generality (i.e. mean number of prey per predator. This diverse prey base and sources of carrion may have facilitated the natural establishment of coyotes on the island. Also, there is some evidence that the introduction of non-native prey species such as the southern red-backed vole has contributed to the recovery of the threatened American marten. Long-term monitoring of the food web is required to understand and predict the impacts of the diverse novel interactions that are developing in the terrestrial mammal food web of Newfoundland.

  5. Monitoring the effects of atmospheric ethylene near polyethylene manufacturing plants with two sensitive plant species

    Energy Technology Data Exchange (ETDEWEB)

    Tonneijck, A.E.G.; Berge, W.F. ten; Jansen, B.P

    2003-05-01

    Atmospheric ethylene from polyethylene manufacturing plants adversely affected the number of flowers and growth of field-grown marigold and petunia. - Data of a multi-year (1977-1983) biomonitoring programme with marigold and petunia around polyethylene manufacturing plants was analysed to assess plant responses to atmospheric ethylene and to determine the area at risk for the phytotoxic effects of this pollutant. In both species, flower formation and growth were severely reduced close to the emission sources and plant performance improved with increasing distance. Plants exposed near the border of the research area had more flowers than the unexposed control while their growth was normal. Measurements of ethylene concentrations at a border site revealed that the growing season mean was 61.5 {mu}g m{sup -3} in 1982 and 15.6 {mu}g m{sup -3} in 1983. In terms of number of flowers, petunia was more sensitive than marigold and adverse effects were observed within ca. 400 m distance from the sources for marigold and within ca. 460 m for petunia. The area at risk (ca. 870 m) for ethylene-induced growth reduction was also limited to the industrial zone. Plants were more sensitive to ethylene in terms of growth reduction than in terms of inhibition of flowering. In the Netherlands, maximum permissible levels of ethylene are currently based on information from laboratory and greenhouse studies. Our results indicate that these levels are rather conservative in protecting field-grown plants against ethylene-induced injury near polyethylene manufacturing plants.

  6. Wild Plant Species with Extremely Small Populations Require Conservation and Reintroduction in China

    Science.gov (United States)

    Hai Ren; Qianmei Zhang; Hongfang Lu; Hongxiao Liu; Qinfeng Guo; Jun Wang; Shuguang Jian; Hai’ou Bao

    2012-01-01

    China is exceptionally rich in biodiversity, with more than 30000 vascular plant species that include many endemic genera, species of ancient origin, and cultivated plants (Yang et al. 2005). Because of rapid economic development, population growth, pollution, and continuing resource exploitation, China’s plant diversity faces severe threats. According to the Chinese...

  7. Fire and invasive exotic plant species in eastern oak communities: an assessment of current knowledge

    Science.gov (United States)

    Cynthia D. Huebner

    2006-01-01

    Successful regeneration of oak-dominated communities in the Eastern United States historically requires disturbance such as fire, making them vulnerable to invasion by exotic plants. Little is currently known about the effects of fire on invasive plant species and the effects of invasive plant species on fire regimes of this region. Seventeen common eastern invaders...

  8. Density-dependency and plant-soil feedback: former plant abundance influences competitive interactions between two grassland plant species through plant-soil feedbacks

    NARCIS (Netherlands)

    Xue, W.; Bezemer, T.M.; Berendse, Frank

    2018-01-01

    Backgrounds and aims Negative plant-soil feedbacks (PSFs) are thought to promote species coexistence, but most evidence is derived from theoretical models and data from plant monoculture experiments. Methods We grew Anthoxanthum odoratum and Centaurea jacea in field plots in monocultures and in

  9. A new Legionella species, Legionella feeleii species nova, causes Pontiac fever in an automobile plant.

    Science.gov (United States)

    Herwaldt, L A; Gorman, G W; McGrath, T; Toma, S; Brake, B; Hightower, A W; Jones, J; Reingold, A L; Boxer, P A; Tang, P W

    1984-03-01

    From 15 to 21 August 1981, Pontiac fever affected 317 automobile assembly plant workers. Results of serologic tests were negative for Mycoplasma, Chlamydia, respiratory tract viruses, and previously described legionellae. A gram-negative, rod-shaped organism (WO-44C) that did not grow on blood agar, required L-cysteine for growth, and contained large amounts of branched-chain fatty acids was isolated from a water-based coolant. The organism did not react with antisera against other legionellae, and on DNA hybridization the organism was less than 10% related to other Legionella species. Geometric mean titers found by indirect fluorescent antibody testing to WO-44C were significantly higher in ill employees than in controls (p = 0.0001). Attack rates by department decreased linearly with the department's distance from the implicated coolant system. The etiologic agent apparently was a new Legionella species; we propose the name Legionella feeleii species nova (AATC 35072). This is the first outbreak of nonpneumonic legionellosis in which the etiologic agent is not L. pneumophila, serogroup 1.

  10. Host plant use among closely related Anaea butterfly species (Lepidoptera, Nymphalidae, Charaxinae

    Directory of Open Access Journals (Sweden)

    QUEIROZ J. M.

    2002-01-01

    Full Text Available There is a great number of Charaxinae (Lepidoptera: Nymphalidae species in the tropics whose larvae feed on several plant families. However the genus Anaea is almost always associated with Croton species (Euphorbiaceae. This work describes patterns of host plant use by immature and adult abundance on different vertical strata of sympatric Anaea species in a forest of Southeastern Brazil. Quantitative samples of leaves were taken in April/1999 and May/2000 to collect eggs and larvae of four Anaea species on C.alchorneicarpus, C. floribundus and C. salutaris in a semideciduous forest. Sampled leaves were divided into three classes of plant phenological stage: saplings, shrubs and trees. The results showed that the butterfly species are segregating in host plant use on two scales: host plant species and plant phenological stages. C. alchorneicarpus was used by only one Anaea species, whereas C. floribundus was used by three species and C. salutaris by four Anaea species. There was one Anaea species concentrated on sapling, another on sapling/shrub and two others on shrub/tree leaves. Adults of Anaea were more frequent at canopy traps but there were no differences among species caught in traps at different vertical positions. This work supplements early studies on host plant use among Charaxinae species and it describes how a guild of closely related butterfly species may be organized in a complex tropical habitat.

  11. Effects of an invasive plant species, celastrus orbiculatus, on soil composition and processes

    Science.gov (United States)

    Leicht-Young, S. A.; O'Donnell, H.; Latimer, A.M.; Silander, J.A.

    2009-01-01

    Celastrus orbiculatus is a non-native, invasive liana that was introduced to the United States in the 1860s and has spread rapidly throughout the Northeast Several attributes contribute to the invasiveness of C. orbiculatus, including tolerance to a wide range of light levels and habitat types. We compared soil characteristics in seven sets of adjacent, paired plots, spanning a range of habitats and soil types, with and without C. orbiculatus. The paired plots were similar other than the presence or absence of Celastrus. Plots with C. orbiculatus had significantly higher soil pH, potassium, calcium and magnesium levels. Furthermore, nitrogen mineralization and litter decomposition rates were higher in plots with C. orbiculatus. Phosphorus levels were not significantly different between the paired plots. The results of this study contribute to the growing body of research of the effects of invasive species on ecosystem processes.

  12. Alien plant species list and distribution for Camdeboo National Park, Eastern Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    Mmoto L. Masubelele

    2009-09-01

    Full Text Available Protected areas globally are threatened by the potential negative impacts that invasive alien plants pose, and Camdeboo National Park (CNP, South Africa, is no exception. Alien plants have been recorded in the CNP since 1981, before it was proclaimed a national park by South African National Parks in 2005. This is the first publication of a list of alien plants in and around the CNP. Distribution maps of some of the first recorded alien plant species are also presented and discussed. To date, 39 species of alien plants have been recorded, of which 13 are invasive and one is a transformer weed. The majority of alien plant species in the park are herbaceous (39% and succulent (24% species. The most widespread alien plant species in the CNP are Atriplex inflata (= A. lindleyi subsp. inflata, Salsola tragus (= S. australis and cacti species, especially Opuntia ficus-indica. Eradication and control measures that have been used for specific problematic alien plant species are described. Conservation implications: This article represents the first step in managing invasive alien plants and includes the collation of a species list and basic information on their distribution in and around the protected area. This is important for enabling effective monitoring of both new introductions and the distribution of species already present. We present the first species list and distribution information for Camdeboo National Park.

  13. Plant trait-species abundance relationships vary with environmental properties in subtropical forests in eastern china.

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    En-Rong Yan

    Full Text Available Understanding how plant trait-species abundance relationships change with a range of single and multivariate environmental properties is crucial for explaining species abundance and rarity. In this study, the abundance of 94 woody plant species was examined and related to 15 plant leaf and wood traits at both local and landscape scales involving 31 plots in subtropical forests in eastern China. Further, plant trait-species abundance relationships were related to a range of single and multivariate (PCA axes environmental properties such as air humidity, soil moisture content, soil temperature, soil pH, and soil organic matter, nitrogen (N and phosphorus (P contents. At the landscape scale, plant maximum height, and twig and stem wood densities were positively correlated, whereas mean leaf area (MLA, leaf N concentration (LN, and total leaf area per twig size (TLA were negatively correlated with species abundance. At the plot scale, plant maximum height, leaf and twig dry matter contents, twig and stem wood densities were positively correlated, but MLA, specific leaf area, LN, leaf P concentration and TLA were negatively correlated with species abundance. Plant trait-species abundance relationships shifted over the range of seven single environmental properties and along multivariate environmental axes in a similar way. In conclusion, strong relationships between plant traits and species abundance existed among and within communities. Significant shifts in plant trait-species abundance relationships in a range of environmental properties suggest strong environmental filtering processes that influence species abundance and rarity in the studied subtropical forests.

  14. Vascular Plant and Vertebrate Inventory of Organ Pipe Cactus National Monument

    Science.gov (United States)

    Schmidt, Cecilia A.; Powell, Brian F.; Halvorson, William L.

    2007-01-01

    Executive Summary We summarized inventory and monitoring efforts for plants and vertebrates at Organ Pipe Cactus National Monument (NM) in Arizona. We used data from previous research to compile complete species lists for the monument and to assess inventory completeness. There have been 1,031 species of plants and vertebrates observed at the monument. Most of the species on the list are documented by voucher specimens. There are 59 non-native species established in the monument: one mammal, three birds, and 55 non-native plants. Most non-native plant species were first recorded along roads. In each taxon-specific chapter, we highlight areas that contribute disproportionately to species richness or that have unique species for the monument. Of particular importance are Quitobaquito Springs and Pond, which are responsible for the monument having one of the highest number of bird species in the Sonoran Desert Network of parks. Quitobaquito also contains the only fish in the monument, the endangered Quitobaquito pupfish (Cyprinodon eremus). Other important resources for the plants and vertebrates include the xeroriparian washes (e.g., Alamo Canyon) and the Ajo Mountains. Based on the review of past studies, we believe the inventories of vascular plants and vertebrates are nearly complete and that the monument has one of the most complete inventories of any unit in the Sonoran Desert Network.

  15. Differential responses of soil bacteria, fungi, archaea and protists to plant species richness and plant functional group identity

    NARCIS (Netherlands)

    Dassen, S.; Cortois, R.; Martens, Henk; De Hollander, M.; Kowalchuk, G.A.; van der Putten, W.H.; De Deyn, G.B.

    2017-01-01

    Plants are known to influence belowground microbial community structure along their roots, but the impacts of plant species richness and plant functional group (FG) identity on microbial communities in the bulk soil are still not well understood. Here, we used 454-pyrosequencing to analyse the soil

  16. Interspecific competition of early successional plant species in ex-arable fields as influenced by plant-soil feedback

    NARCIS (Netherlands)

    Jing, Jingying; Bezemer, T. Martijn; Van der Putten, Wim H.

    2015-01-01

    Plant–soil feedback can affect plants that belong to the same (intraspecific feedback) or different species (interspecific feedback). However, little is known about how intra- and interspecific plant–soil feedbacks influence interspecific plant competition. Here, we used plants and soil from

  17. Changes in semi-arid plant species associations along a livestock grazing gradient.

    Directory of Open Access Journals (Sweden)

    Hugo Saiz

    Full Text Available In semi-arid ecosystems, vegetation is heterogeneously distributed, with plant species often associating in patches. These associations between species are not constant, but depend on the particular response of each species to environmental factors. Here, we investigated how plant species associations change in response to livestock grazing in a semi-arid ecosystem, Cabo de Gata-Níjar Natural Park in South East Spain. We established linear point-intercept transects at four sites with different grazing intensity, and recorded all species at each point. We investigated plant associations by comparing the number of times that each pair of species occurred at the same spatial point (co-occurrences, with the expected number of times based on species abundances. We also assessed associations for each shrub and grass species by considering all their pairs of associations and for the whole plant community by considering all pairs of associations on each site. At all sites, the plant community had a negative pattern of association, with fewer co-occurrences than expected. Negative association in the plant community increased at maximum grazing intensity. Most species associated as expected, particularly grass species, and positive associations were most important at intermediate grazing intensities. No species changed its type of association along the grazing gradient. We conclude that in the present plant community, grazing-resistant species compete among themselves and segregate in space. Some shrub species act as refuges for grazing-sensitive species that benefit from being spatially associated with shrub species, particularly at intermediate grazing intensities where positive associations were highest. At high grazing intensity, these shrubs can no longer persist and positive associations decrease due to the disappearance of refuges. Spatial associations between plant species and their response to grazing help identify the factors that organize

  18. Plant species distribution along environmental gradient: do belowground interactions with fungi matter?

    Directory of Open Access Journals (Sweden)

    Loïc ePellissier

    2013-12-01

    Full Text Available The distribution of plants along environmental gradients is constrained by abiotic and biotic factors. Cumulative evidence attests of the impact of abiotic factors on plant distributions, but only few studies discuss the role of belowground communities. Soil fungi, in particular, are thought to play an important role in how plant species assemble locally into communities. We first review existing evidence, and then test the effect of the number of soil fungal operational taxonomic units (OTUs on plant species distributions using a recently collected dataset of plant and metagenomic information on soil fungi in the Western Swiss Alps. Using species distribution models, we investigated whether the distribution of individual plant species is correlated to the number of OTUs of two important soil fungal classes known to interact with plants: the Glomeromycetes, that are obligatory symbionts of plants, and the Agaricomycetes, that may be facultative plant symbionts, pathogens, or wood decayers. We show that including the fungal richness information in the models of plant species distributions improves predictive accuracy. Number of fungal OTUs is especially correlated to the distribution of high elevation plant species. We suggest that high elevation soil show greater variation in fungal assemblages that may in turn impact plant turnover among communities. We finally discuss how to move beyond correlative analyses, through the design of field experiments manipulating plant and fungal communities along environmental gradients.

  19. Changes in plant species richness induce functional shifts in soil nematode communities in experimental grassland.

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    Nico Eisenhauer

    Full Text Available Changes in plant diversity may induce distinct changes in soil food web structure and accompanying soil feedbacks to plants. However, knowledge of the long-term consequences of plant community simplification for soil animal food webs and functioning is scarce. Nematodes, the most abundant and diverse soil Metazoa, represent the complexity of soil food webs as they comprise all major trophic groups and allow calculation of a number of functional indices.We studied the functional composition of nematode communities three and five years after establishment of a grassland plant diversity experiment (Jena Experiment. In response to plant community simplification common nematode species disappeared and pronounced functional shifts in community structure occurred. The relevance of the fungal energy channel was higher in spring 2007 than in autumn 2005, particularly in species-rich plant assemblages. This resulted in a significant positive relationship between plant species richness and the ratio of fungal-to-bacterial feeders. Moreover, the density of predators increased significantly with plant diversity after five years, pointing to increased soil food web complexity in species-rich plant assemblages. Remarkably, in complex plant communities the nematode community shifted in favour of microbivores and predators, thereby reducing the relative abundance of plant feeders after five years.The results suggest that species-poor plant assemblages may suffer from nematode communities detrimental to plants, whereas species-rich plant assemblages support a higher proportion of microbivorous nematodes stimulating nutrient cycling and hence plant performance; i.e. effects of nematodes on plants may switch from negative to positive. Overall, food web complexity is likely to decrease in response to plant community simplification and results of this study suggest that this results mainly from the loss of common species which likely alter plant-nematode interactions.

  20. The role of web sharing, species recognition and host-plant defence in interspecific competition between two herbivorous mite species.

    Science.gov (United States)

    Sato, Yukie; Alba, Juan M; Egas, Martijn; Sabelis, Maurice W

    2016-11-01

    When competing with indigenous species, invasive species face a problem, because they typically start with a few colonizers. Evidently, some species succeeded, begging an answer to the question how they invade. Here, we investigate how the invasive spider mite Tetranychus evansi interacts with the indigenous species T. urticae when sharing the solanaceous host plant tomato: do they choose to live together or to avoid each other's colonies? Both species spin protective, silken webs on the leaf surfaces, under which they live in groups of con- and possibly heterospecifics. In Spain, T. evansi invaded the non-crop field where native Tetranychus species including T. urticae dominated. Moreover, T. evansi outcompetes T. urticae when released together on a tomato plant. However, molecular plant studies suggest that T. urticae benefits from the local down-regulation of tomato plant defences by T. evansi, whereas T. evansi suffers from the induction of these defences by T. urticae. Therefore, we hypothesize that T. evansi avoids leaves infested with T. urticae whereas T. urticae prefers leaves infested by T. evansi. Using wild-type tomato and a mutant lacking jasmonate-mediated anti-herbivore defences, we tested the hypothesis and found that T. evansi avoided sharing webs with T. urticae in favour of a web with conspecifics, whereas T. urticae more frequently chose to share webs with T. evansi than with conspecifics. Also, T. evansi shows higher aggregation on a tomato plant than T. urticae, irrespective of whether the mites occur on the plant together or not.

  1. Plant species occurrence patterns in Eurasian grasslands reflect adaptation to nutrient ratios

    NARCIS (Netherlands)

    Roeling, Ineke S.; Ozinga, Wim A.; van Dijk, Jerry; Eppinga, Maarten B.; Wassen, Martin J.

    2018-01-01

    Previous studies of Eurasian grasslands have suggested that nutrient ratios, rather than absolute nutrient availabilities and associated productivity, may be driving plant species richness patterns. However, the underlying assumption that species occupy distinct niches along nutrient ratio gradients

  2. Reciprocal effects of litter from exotic and congeneric native plant species via soil nutrients.

    Directory of Open Access Journals (Sweden)

    Annelein Meisner

    Full Text Available Invasive exotic plant species are often expected to benefit exclusively from legacy effects of their litter inputs on soil processes and nutrient availability. However, there are relatively few experimental tests determining how litter of exotic plants affects their own growth conditions compared to congeneric native plant species. Here, we test how the legacy of litter from three exotic plant species affects their own performance in comparison to their congeneric natives that co-occur in the invaded habitat. We also analyzed litter effects on soil processes. In all three comparisons, soil with litter from exotic plant species had the highest respiration rates. In two out of the three exotic-native species comparisons, soil with litter from exotic plant species had higher inorganic nitrogen concentrations than their native congener, which was likely due to higher initial litter quality of the exotics. When litter from an exotic plant species had a positive effect on itself, it also had a positive effect on its native congener. We conclude that exotic plant species develop a legacy effect in soil from the invaded range through their litter inputs. This litter legacy effect results in altered soil processes that can promote both the exotic plant species and their native congener.

  3. 78 FR 40669 - Endangered and Threatened Wildlife and Plants; Endangered Species Status for Cape Sable...

    Science.gov (United States)

    2013-07-08

    ... and Plants; Endangered Species Status for Cape Sable Thoroughwort, Florida Semaphore Cactus, and... thoroughwort), Consolea corallicola (Florida semaphore cactus), and Harrisia aboriginum (aboriginal prickly...

  4. Minimal effectiveness of native and non-native seeding following three high-severity wildfire

    Science.gov (United States)

    Ken A. Stella; Carolyn H. Sieg; Pete Z. Fule

    2010-01-01

    The rationale for seeding following high-severity wildfires is to enhance plant cover and reduce bare ground, thus decreasing the potential for soil erosion and non-native plant invasion. However, experimental tests of the effectiveness of seeding in meeting these objectives in forests are lacking. We conducted three experimental studies of the effectiveness of seeding...

  5. Performance of dryland and wetland plant species on extensive green roofs.

    Science.gov (United States)

    MacIvor, J Scott; Ranalli, Melissa A; Lundholm, Jeremy T

    2011-04-01

    Green roofs are constructed ecosystems where plants perform valuable services, ameliorating the urban environment through roof temperature reductions and stormwater interception. Plant species differ in functional characteristics that alter ecosystem properties. Plant performance research on extensive green roofs has so far indicated that species adapted to dry conditions perform optimally. However, in moist, humid climates, species typical of wetter soils might have advantages over dryland species. In this study, survival, growth and the performance of thermal and stormwater capture functions of three pairs of dryland and wetland plant species were quantified using an extensive modular green roof system. Seedlings of all six species were germinated in a greenhouse and planted into green roof modules with 6 cm of growing medium. There were 34 treatments consisting of each species in monoculture and all combinations of wet- and dryland species in a randomized block design. Performance measures were survival, vegetation cover and roof surface temperature recorded for each module over two growing seasons, water loss (an estimate of evapotranspiration) in 2007, and albedo and water capture in 2008. Over two seasons, dryland plants performed better than wetland plants, and increasing the number of dryland species in mixtures tended to improve functioning, although there was no clear effect of species or habitat group diversity. All species had survival rates >75 % after the first winter; however, dryland species had much greater cover, an important indicator of green roof performance. Sibbaldiopsis tridentata was the top performing species in monoculture, and was included in the best treatments. Although dryland species outperformed wetland species, planting extensive green roofs with both groups decreased performance only slightly, while increasing diversity and possibly habitat value. This study provides further evidence that plant composition and diversity can

  6. Fifteen-Year Growth of Six Planted Hardwood Species on Sharkey Clay Soil

    Science.gov (United States)

    Roger M. Krinard; Harvey E. Kennedy

    1987-01-01

    Six hardwood species planted on Sharkey clay soil that had been disked the first 5 years for weed control were significantly taller at age 5 when compared to species grown on mowed sites. By age 15, there were no differences in heights within species except for sweet pecan. Average heights by species at age 15 were: cottonwood (Populus deltoides...

  7. Species richness and patterns of invasion in plants, birds, and fishes in the United States

    Science.gov (United States)

    Thomas J. Stohlgren; David T. Barnett; Curtis H. Flather; Pam L. Fuller; Bruce G. Peterjohn; John T. Kartesz; Lawrence L. Master

    2006-01-01

    We quantified broad-scale patterns of species richness and species density (mean # species/km2) for native and non-indigenous plants, birds, and fishes in the continental USA and Hawaii. We hypothesized that the species density of native and non-indigenous taxa would generally decrease in northern latitudes and higher elevations following...

  8. Vascular plant and vertebrate species richness in national parks of the eastern United States

    Science.gov (United States)

    Hatfield, Jeffrey S.; Myrick, Kaci E.; Huston, Michael A.; Weckerly, Floyd W.; Green, M. Clay

    2013-01-01

    Given the estimates that species diversity is diminishing at 50-100 times the normal rate, it is critical that we be able to evaluate changes in species richness in order to make informed decisions for conserving species diversity. In this study, we examined the potential of vascular plant species richness to be used as a surrogate for vertebrate species richness in the classes of amphibians, reptiles, birds, and mammals. Vascular plants, as primary producers, represent the biotic starting point for ecological community structure and are the logical place to start for understanding vertebrate species associations. We used data collected by the United States (US) National Park Service (NPS) on species presence within parks in the eastern US to estimate simple linear regressions between plant species richness and vertebrate richness. Because environmental factors may also influence species diversity, we performed simple linear regressions of species richness versus natural logarithm of park area, park latitude, mean annual precipitation, mean annual temperature, and human population density surrounding the parks. We then combined plant species richness and environmental variables in multiple regressions to determine the variables that remained as significant predictors of vertebrate species richness. As expected, we detected significant relationships between plant species richness and amphibian, bird, and mammal species richness. In some cases, plant species richness was predicted by park area alone. Species richness of mammals was only related to plant species richness. Reptile species richness, on the other hand, was related to plant species richness, park latitude and annual precipitation, while amphibian species richness was related to park latitude, park area, and plant species richness. Thus, plant species richness predicted species richness of different vertebrate groups to varying degrees and should not be used exclusively as a surrogate for vertebrate

  9. Species diversity of vascular plants in Si Phang-nga National Park, Phangnga Province

    Directory of Open Access Journals (Sweden)

    Leeratiwong, C.

    2005-07-01

    Full Text Available A survey of the vascular plants in Si Phang-nga National Park, Phangnga Province, was conducted from September 2002 to August 2003. Five hundred and forty three species of 287 genera and 111 families were collected. The most diverse family was Rubiaceae, 53 species. Four species of these collected plants are endemic to Thailand, Argostemma lobulatum, Aristolochia helix, Crinum thaianum and Mallotus hymenophyllus and three species, Hedyotis hedyotidea, Lipocarpha microcephala and Pterolobium intergum are newly recorded for southern Thailand.

  10. Disjunct populations of European vascular plant species keep the same climatic niches

    DEFF Research Database (Denmark)

    Wasof, Safaa; Lenoir, Jonathan; Aarrestad, Per Arild

    2015-01-01

    separated for thousands of years. Location: European Alps and Fennoscandia. Methods: Of the studied pool of 888 terrestrial vascular plant species occurring in both the Alps and Fennoscandia, we used two complementary approaches to test and quantify climatic-niche shifts for 31 species having strictly......Aim: Previous research on how climatic niches vary across species ranges has focused on a limited number of species, mostly invasive, and has not, to date, been very conclusive. Here we assess the degree of niche conservatism between distant populations of native alpine plant species that have been...... to be largely valid for arctic-alpine plants....

  11. Extensive analysis of native and non-native Centaurea solstitialis L. populations across the world shows no traces of polyploidization

    Directory of Open Access Journals (Sweden)

    Ramona-Elena Irimia

    2017-08-01

    Full Text Available Centaurea solstitialis L. (yellow starthistle, Asteraceae is a Eurasian native plant introduced as an exotic into North and South America, and Australia, where it is regarded as a noxious invasive. Changes in ploidy level have been found to be responsible for numerous plant biological invasions, as they are involved in trait shifts critical to invasive success, like increased growth rate and biomass, longer life-span, or polycarpy. C. solstitialis had been reported to be diploid (2n = 2x = 16 chromosomes, however, actual data are scarce and sometimes contradictory. We determined for the first time the absolute nuclear DNA content by flow cytometry and estimated ploidy level in 52 natural populations of C. solstitialis across its native and non-native ranges, around the world. All the C. solstitialis populations screened were found to be homogeneously diploid (average 2C value of 1.72 pg, SD = ±0.06 pg, with no significant variation in DNA content between invasive and non-invasive genotypes. We did not find any meaningful difference among the extensive number of native and non-native C. solstitialis populations sampled around the globe, indicating that the species invasive success is not due to changes in genome size or ploidy level.

  12. Extensive analysis of native and non-native Centaurea solstitialis L. populations across the world shows no traces of polyploidization.

    Science.gov (United States)

    Irimia, Ramona-Elena; Montesinos, Daniel; Eren, Özkan; Lortie, Christopher J; French, Kristine; Cavieres, Lohengrin A; Sotes, Gastón J; Hierro, José L; Jorge, Andreia; Loureiro, João

    2017-01-01

    Centaurea solstitialis L. (yellow starthistle, Asteraceae) is a Eurasian native plant introduced as an exotic into North and South America, and Australia, where it is regarded as a noxious invasive. Changes in ploidy level have been found to be responsible for numerous plant biological invasions, as they are involved in trait shifts critical to invasive success, like increased growth rate and biomass, longer life-span, or polycarpy. C . solstitialis had been reported to be diploid (2 n  = 2 x  = 16 chromosomes), however, actual data are scarce and sometimes contradictory. We determined for the first time the absolute nuclear DNA content by flow cytometry and estimated ploidy level in 52 natural populations of C . solstitialis across its native and non-native ranges, around the world. All the C. solstitialis populations screened were found to be homogeneously diploid (average 2C value of 1.72 pg, SD = ±0.06 pg), with no significant variation in DNA content between invasive and non-invasive genotypes. We did not find any meaningful difference among the extensive number of native and non-native C . solstitialis populations sampled around the globe, indicating that the species invasive success is not due to changes in genome size or ploidy level.

  13. Managing conflicts arising from fisheries enhancements based on non-native fishes in southern Africa.

    Science.gov (United States)

    Ellender, B R; Woodford, D J; Weyl, O L F; Cowx, I G

    2014-12-01

    Southern Africa has a long history of non-native fish introductions for the enhancement of recreational and commercial fisheries, due to a perceived lack of suitable native species. This has resulted in some important inland fisheries being based on non-native fishes. Regionally, these introductions are predominantly not benign, and non-native fishes are considered one of the main threats to aquatic biodiversity because they affect native biota through predation, competition, habitat alteration, disease transfer and hybridization. To achieve national policy objectives of economic development, food security and poverty eradication, countries are increasingly looking towards inland fisheries as vehicles for development. As a result, conflicts have developed between economic and conservation objectives. In South Africa, as is the case for other invasive biota, the control and management of non-native fishes is included in the National Environmental Management: Biodiversity Act. Implementation measures include import and movement controls and, more recently, non-native fish eradication in conservation priority areas. Management actions are, however, complicated because many non-native fishes are important components in recreational and subsistence fisheries that contribute towards regional economies and food security. In other southern African countries, little attention has focussed on issues and management of non-native fishes, and this is cause for concern. This paper provides an overview of introductions, impacts and fisheries in southern Africa with emphasis on existing and evolving legislation, conflicts, implementation strategies and the sometimes innovative approaches that have been used to prioritize conservation areas and manage non-native fishes. © 2014 The Fisheries Society of the British Isles.

  14. Granivory of invasive, naturalized, and native plants in communities differentially susceptible to invasion

    Science.gov (United States)

    B. M. Connolly; D. E. Pearson; R. N. Mack

    2014-01-01

    Seed predation is an important biotic filter that can influence abundance and spatial distributions of native species through differential effects on recruitment. This filter may also influence the relative abundance of nonnative plants within habitats and the communities' susceptibility to invasion via differences in granivore identity, abundance, and food...

  15. Fort Collins Science Center: Invasive Species Science

    Science.gov (United States)

    Stohlgren, Tom

    2004-01-01

    Invasive, non-native species of plants, animals, and disease organisms adversely affect the ecosystems they enter. Like "biological wildfires," they can quickly spread, and they affect nearly all terrestrial and aquatic ecosystems. Invasive species have become the greatest environmental challenge of the 21st century in terms of economic, environmental, and human health costs, with an estimated impact in the U.S. of over $138 billion per year. Managers of Department of the Interior and other public and private lands and waters rank invasive species as their top resource management problem.

  16. Word Durations in Non-Native English

    Science.gov (United States)

    Baker, Rachel E.; Baese-Berk, Melissa; Bonnasse-Gahot, Laurent; Kim, Midam; Van Engen, Kristin J.; Bradlow, Ann R.

    2010-01-01

    In this study, we compare the effects of English lexical features on word duration for native and non-native English speakers and for non-native speakers with different L1s and a range of L2 experience. We also examine whether non-native word durations lead to judgments of a stronger foreign accent. We measured word durations in English paragraphs read by 12 American English (AE), 20 Korean, and 20 Chinese speakers. We also had AE listeners rate the `accentedness' of these non-native speakers. AE speech had shorter durations, greater within-speaker word duration variance, greater reduction of function words, and less between-speaker variance than non-native speech. However, both AE and non-native speakers showed sensitivity to lexical predictability by reducing second mentions and high frequency words. Non-native speakers with more native-like word durations, greater within-speaker word duration variance, and greater function word reduction were perceived as less accented. Overall, these findings identify word duration as an important and complex feature of foreign-accented English. PMID:21516172

  17.  Invasibility of three major non-native invasive shrubs and associated factors in Upper Midwest U.S. forest lands

    Science.gov (United States)

    W. Keith Moser; Zhaofei Fan; Mark H. Hansen; Michael K. Crosby; Shirley X. Fan

    2016-01-01

    We used non-native invasive plant data from the US Forest Service’s Forest Inventory and Analysis (FIA) program, spatial statistical methods, and the space (cover class)-for-time approach to quantify the invasion potential and success ("invasibility") of three major invasive shrubs (multiflora rose, non-native bush honeysuckles, and common buckthorn...

  18. Mapping National Plant Biodiversity Patterns in South Korea with the MARS Species Distribution Model.

    Directory of Open Access Journals (Sweden)

    Hyeyeong Choe

    Full Text Available Accurate information on the distribution of existing species is crucial to assess regional biodiversity. However, data inventories are insufficient in many areas. We examine the ability of Multivariate Adaptive Regression Splines (MARS multi-response species distribution model to overcome species' data limitations and portray plant species distribution patterns for 199 South Korean plant species. The study models species with two or more observations, examines their contribution to national patterns of species richness, provides a sensitivity analysis of different range threshold cutoff approaches for modeling species' ranges, and presents considerations for species modeling at fine spatial resolution. We ran MARS models for each species and tested four threshold methods to transform occurrence probabilities into presence or absence range maps. Modeled occurrence probabilities were extracted at each species' presence points, and the mean, median, and one standard deviation (SD calculated to define data-driven thresholds. A maximum sum of sensitivity and specificity threshold was also calculated, and the range maps from the four cutoffs were tested using independent plant survey data. The single SD values were the best threshold tested for minimizing omission errors and limiting species ranges to areas where the associated occurrence data were correctly classed. Eight individual species range maps for rare plant species were identified that are potentially affected by resampling predictor variables to fine spatial scales. We portray spatial patterns of high species richness by assessing the combined range maps from three classes of species: all species, endangered and endemic species, and range-size rarity of all species, which could be used in conservation planning for South Korea. The MARS model is promising for addressing the common problem of few species occurrence records. However, projected species ranges are highly dependent on the

  19. Nutritional and cultural aspects of plant species selection for a controlled ecological life support system

    Science.gov (United States)

    Hoff, J. E.; Howe, J. M.; Mitchell, C. A.

    1982-01-01

    The feasibility of using higher plants in a controlled ecological life support system is discussed. Aspects of this system considered important in the use of higher plants include: limited energy, space, and mass, and problems relating to cultivation and management of plants, food processing, the psychological impact of vegetarian diets, and plant propagation. A total of 115 higher plant species are compared based on 21 selection criteria.

  20. Investigating Effects of Invasive Species on Plant Community Structure

    Science.gov (United States)

    Franklin, Wilfred

    2008-01-01

    In this article, the author presents a field study project that explores factors influencing forest community structure and lifts the veil off of "plant blindness." This ecological study consists of three laboratories: (1) preliminary field trip to the study site; (2) plant survey; and (3) analyzing plant community structure with descriptive…

  1. Invasion by non-native brook trout in Panther Creek, Idaho: Roles of habitat quality, biotic resistance, and connectivity to source habitats

    Science.gov (United States)

    Joseph R. Benjamin; Jason B. Dunham; Matthew R. Dare

    2007-01-01

    Theoretical models and empirical evidence suggest that the invasion of nonnative species in freshwaters is facilitated through the interaction of three factors: habitat quality, biotic resistance, and connectivity. We measured variables that represented each factor to determine which were associated with the occurrence of nonnative brook trout Salvelinus...

  2. Global compositional variation among native and non-native regional insect assemblages emphasizes the importance of pathways

    Science.gov (United States)

    Andrew M. Liebhold; Takehiko Yamanaka; Alain Roques; Sylvie Augustin; Steven L. Chown; Eckehard G. Brockerhoff; Petr Pysek

    2016-01-01

    Insects are among the world's most ecologically and economically important invasive species. Here we assemble inventories of native and nonnative species from 20 world regions and contrast relative numbers among these species assemblages. Multivariate ordination indicates that the distribution of species among insect orders is completely different between native...

  3. [Relation between species distribution of plant community and soil factors under grazing in alpine meadow].

    Science.gov (United States)

    Niu, Yu Jie; Yang, Si Wei; Wang, Gui Zhen; Liu, Li; Du, Guo Zhen; Hua, Li Min

    2017-12-01

    The research selected the alpine meadow located in the northeastern margin of the Qinghai-Tibet Plateau to study the changes of vegetation community and soil properties under different grazing intensities, as well as the quantitative relation between the distribution patterns of plant species and the physical and chemical properties of soil. The results showed that the grazing caused the differentiation of the initial vegetation community with the dominant plants, Elymus nutans and Stipa grandis. In the plots with high and low grazing intensities, the dominant plants had changed to Kobresia humilis and Melissitus ruthenica, and E. nutans and Poa crymophila, respectively. With the increase of grazing intensity, the plant richness, importance value and biomass were significantly decreased. The sequence of plant species importance value in each plot against grazing intensity could be fitted by a logarithmic model. The number of required plant species was reduced while the importance value of the remaining plant species accounted for 50% of the importance value in the whole vegetation community. The available P, available K, soil compaction, soil water content, stable infiltration rate and large aggregate index were significantly changed with grazing intensity, however, the changes were different. The CCA ordination showed that the soil compaction was the key factor affecting the distribution pattern of the plant species under grazing. The variance decomposition indicated that the soil factors together explained 30.5% of the distribution of the plant species, in particular the soil physical properties alone explained 22.8% of the distribution of the plant species, which had the highest rate of contribution to the plant species distribution. The soil physical properties affected the distribution pattern of plant species on grazed alpine meadow.

  4. Fire frequency and tree canopy structure influence plant species diversity in a forest-grassland ecotone

    Science.gov (United States)

    David W. Peterson; Peter B. Reich

    2008-01-01

    Disturbances and environmental heterogeneity are two factors thought to influence plant species diversity, but their effects are still poorly understood in many ecosystems. We surveyed understory vegetation and measured tree canopy cover on permanent plots spanning an experimental fire frequency gradient to test fire frequency and tree canopy effects on plant species...

  5. Pollinator networks, alien species and the conservation of rare plants: Trinia glauca as a case study

    NARCIS (Netherlands)

    Carvalheiro, L.G.; Barbosa, E.R.; Memmott, J.

    2008-01-01

    1. Despite the essential role of pollination in the maintenance of many rare plant species, conservation management plans rarely consider the service of pollination. 2. This study identifies the main pollinators of a rare English plant species, Trinia glauca (Apiaceae), and provides recommendations

  6. Impact of mine dumps on transport the invasive plant species to Upper Silesia

    Science.gov (United States)

    Sotkova, N.; Lokajickova, B.; Mec, J.; Svehlakova, H.; Stalmachova, B.

    2017-10-01

    Human activities significantly change the species composition in the area. The main factor of change was the mining industry, which changed the natural conditions on Upper Silesia. The anthropogenic relief of mine dumps are the main centre of alien plant in an industrial landscape. The poster deals with the state of the invasive plant species by the phyto-sociological surveys on Upper Silesia.

  7. A non-native prey mediates the effects of a shared predator on an ecosystem service.

    Directory of Open Access Journals (Sweden)

    James E Byers

    Full Text Available Non-native species can alter ecosystem functions performed by native species often by displacing influential native species. However, little is known about how ecosystem functions may be modified by trait-mediated indirect effects of non-native species. Oysters and other reef-associated filter feeders enhance water quality by controlling nutrients and contaminants in many estuarine environments. However, this ecosystem service may be mitigated by predation, competition, or other species interactions, especially when such interactions involve non-native species that share little evolutionary history. We assessed trophic and other interference effects on the critical ecosystem service of water filtration in mesocosm experiments. In single-species trials, typical field densities of oysters (Crassostrea virginica reduced water-column chlorophyll a more strongly than clams (Mercenaria mercenaria. The non-native filter-feeding reef crab Petrolisthes armatus did not draw down chlorophyll a. In multi-species treatments, oysters and clams combined additively to influence chlorophyll a drawdown. Petrolisthes did not affect net filtration when added to the bivalve-only treatments. Addition of the predatory mud crab Panopeus herbstii did not influence oyster feeding rates, but it did stop chlorophyll a drawdown by clams. However, when Petrolisthes was also added in with the clams, the clams filtered at their previously unadulterated rates, possibly because Petrolisthes drew the focus of predators or habituated the clams to crab stimuli. In sum, oysters were the most influential filter feeder, and neither predators nor competitors interfered with their net effect on water-column chlorophyll. In contrast, clams filtered less, but were more sensitive to predators as well as a facilitative buffering effect of Petrolisthes, illustrating that non-native species can indirectly affect an ecosystem service by aiding the performance of a native species.

  8. Herbs versus Trees: Influences on Teenagers' Knowledge of Plant Species

    Science.gov (United States)

    Lückmann, Katrin; Menzel, Susanne

    2014-01-01

    The study reports on species knowledge among German adolescents (n = 507) as: (1) self-assessed evaluation of one's species knowledge; and (2) factual knowledge about popular local herbs and trees. Besides assessing species knowledge, we were interested in whether selected demographic factors, environmental attitude (as measured through the New…

  9. How does biomass distribution change with size and differ among species? An analysis for 1200 plant species from five continents.

    Science.gov (United States)

    Poorter, Hendrik; Jagodzinski, Andrzej M; Ruiz-Peinado, Ricardo; Kuyah, Shem; Luo, Yunjian; Oleksyn, Jacek; Usoltsev, Vladimir A; Buckley, Thomas N; Reich, Peter B; Sack, Lawren

    2015-11-01

    We compiled a global database for leaf, stem and root biomass representing c. 11 000 records for c. 1200 herbaceous and woody species grown under either controlled or field conditions. We used this data set to analyse allometric relationships and fractional biomass distribution to leaves, stems and roots. We tested whether allometric scaling exponents are generally constant across plant sizes as predicted by metabolic scaling theory, or whether instead they change dynamically with plant size. We also quantified interspecific variation in biomass distribution among plant families and functional groups. Across all species combined, leaf vs stem and leaf vs root scaling exponents decreased from c. 1.00 for small plants to c. 0.60 for the largest trees considered. Evergreens had substantially higher leaf mass fractions (LMFs) than deciduous species, whereas graminoids maintained higher root mass fractions (RMFs) than eudicotyledonous herbs. These patterns do not support the hypothesis of fixed allometric exponents. Rather, continuous shifts in allometric exponents with plant size during ontogeny and evolution are the norm. Across seed plants, variation in biomass distribution among species is related more to function than phylogeny. We propose that the higher LMF of evergreens at least partly compensates for their relatively low leaf area : leaf mass ratio. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  10. Phytoremediation of soil co-contaminated with heavy metals and TNT using four plant species.

    Science.gov (United States)

    Lee, Insook; Baek, Kyunghwa; Kim, Hyunhee; Kim, Sunghyun; Kim, Jaisoo; Kwon, Youngseok; Chang, Yoontoung; Bae, Bumhan

    2007-11-01

    We investigated the germination, growth rates and uptake of contaminants of four plant species, barnyard grass (Echinochloa crusgalli), sunflower (Helianthus annuus), Indian mallow (Abutilon avicennae) and Indian jointvetch (Aeschynomene indica), grown in soil contaminated with cadmium (Cd), lead (Pb) and 2,4,6-trinitrotoluene (TNT). These contaminants are typically found at shooting ranges. Experiments were carried out over 180 days using both single plant cultures and cultures containing an equal mix of the 4 plant species. Germination rates differed among the species in single culture (92% for H. annuus, 84% for E. crusgalli, 48% for A. avicennae and 38% Ae. indica). In the 4-plant mix culture, phytoremediation for the removal of heavy metals and TNT from contaminated soils should use a single plant species rather than a mixture of several plants.

  11. Simulated geographic variations of plant species richness, evenness and abundance using climatic constraints on plant functional diversity

    International Nuclear Information System (INIS)

    Kleidon, Axel; Pavlick, Ryan; Reu, Bjoern; Adams, Jonathan

    2009-01-01

    Among the most pronounced large-scale geographic patterns of plant biodiversity are the increase in plant species richness towards the tropics, a more even distribution of the relative abundances of plant species in the tropics, and a nearly log-normal relative abundance distribution. Here we use an individual-based plant diversity model that relates climatic constraints to feasible plant growth strategies to show that all three basic diversity patterns can be predicted merely from the climatic constraints acting upon plant ecophysiological trade-offs. Our model predicts that towards objectively 'harsher' environments, the range of feasible growth strategies resulting in reproductive plants is reduced, thus resulting in lower functional plant species richness. The reduction of evenness is attributed to a more rapid decline in productivity from the most productive to less productive plant growth strategies since the particular setup of the strategy becomes more important in maintaining high productivity in harsher environments. This approach is also able to reproduce the increase in the deviation from a log-normal distribution towards more evenly distributed communities of the tropics. Our results imply that these general biodiversity relationships can be understood primarily by considering the climatic constraints on plant ecophysiological trade-offs.

  12. Stability of modularity and structural keystone species in temporal cumulative plant- flower-visitor networks

    DEFF Research Database (Denmark)

    Dupont, Yoko; Olesen, Jens Mogens

    2012-01-01

    Modularity is a structural property of ecological networks, which has received much interest, but has been poorly explored. Modules are distinct subsets of species interacting strongly with each other, but sparsely with species outside the subset. Using a series of temporal cumulative networks, we...... all flowering plants and flower-visiting insect species throughout the flowering season at three dry heathland sites in Denmark. For each site, we constructed cumulative networks every 0.5 months, resulting in series of 10–12 networks per site. Numbers of interactions, and plant and insect species...... around one or two hubs. These hub species encompassed a small number of plant species, many of which acted as hubs at several study sites and throughout most of their flowering season. Thus, these plants become of key importance in maintaining the structure of their pollination network. We conclude...

  13. Measuring Phenological Changes due to Defoliation of the Non-Native Species, Saltcedar (Tamarisk) Following Episodic Foliage Removal by the Beetle Diorhabda elongate and Phenological Impacts on Forage Quality for Insectivorous Birds on the Dolores River

    Science.gov (United States)

    Nagler, P. L.; Dennison, P. E.; Hultine, K. R.; van Riper, C.; Glenn, E. P.

    2008-12-01

    Since its introduction to the western U.S. more than a century ago, tamarisk (Tamarix spp.) has become dominant or sub-dominant over many major arid, and semi-arid river systems and their tributaries. The presence of tamarisk has been cited for reducing water availability for human enterprise and biodiversity, displacing native vegetation and for reducing habitat quality for wildlife. With increasing emphasis by public and private sectors on controlling saltcedar (Tamarix chinensis) in the western US, there will likely be a dramatic change in riparian vegetation composition over the course of the next several decades. The rates at which these changes will occur, and the resultant effects on riparian insects and birds that utilize insects for food, are presently unknown. Effects on riparian vegetation communities, resulting from changes in host plant species composition, will likely include changes in plant biomass, microclimate changes, and plant species diversity. These changes could potentially have a profound impact on migratory and breeding birds within riparian corridors throughout the southwest. Recently, the saltcedar leaf beetle (Diorhabda elongata) was released as a tamarisk biocontrol agent. This beetle has successfully defoliated tamarisk where it has been introduced, but there are currently no comprehensive programs in place for monitoring the rapid spread of Diorhabda, the impact of defoliation on habitat and water resources, or the long-term impact of defoliation on tamarisk. We used higher spatial resolution ASTER data and coarser MODIS data for monitoring defoliation caused by Diorhabda elongata and subsequent changes in evapotranspiration (ET). Widespread tamarisk defoliation was observed in an eastern Utah study area during summers 2007, 2008. We measured stem sap flux, leaf carbon isotope ratios, leaf area, LAI, and vegetation indices from mounted visible and infrared cameras and satellite imagery. The cameras were paired on towers installed 30

  14. Evaluating complementary networks of restoration plantings for landscape-scale occurrence of temporally dynamic species.

    Science.gov (United States)

    Ikin, Karen; Tulloch, Ayesha; Gibbons, Philip; Ansell, Dean; Seddon, Julian; Lindenmayer, David

    2016-10-01

    Multibillion dollar investments in land restoration make it critical that conservation goals are achieved cost-effectively. Approaches developed for systematic conservation planning offer opportunities to evaluate landscape-scale, temporally dynamic biodiversity outcomes from restoration and improve on traditional approaches that focus on the most species-rich plantings. We investigated whether it is possible to apply a complementarity-based approach to evaluate the extent to which an existing network of restoration plantings meets representation targets. Using a case study of woodland birds of conservation concern in southeastern Australia, we compared complementarity-based selections of plantings based on temporally dynamic species occurrences with selections based on static species occurrences and selections based on ranking plantings by species richness. The dynamic complementarity approach, which incorporated species occurrences over 5 years, resulted in higher species occurrences and proportion of targets met compared with the static complementarity approach, in which species occurrences were taken at a single point in time. For equivalent cost, the dynamic complementarity approach also always resulted in higher average minimum percent occurrence of species maintained through time and a higher proportion of the bird community meeting representation targets compared with the species-richness approach. Plantings selected under the complementarity approaches represented the full range of planting attributes, whereas those selected under the species-richness approach were larger in size. Our results suggest that future restoration policy should not attempt to achieve all conservation goals within individual plantings, but should instead capitalize on restoration opportunities as they arise to achieve collective value of multiple plantings across the landscape. Networks of restoration plantings with complementary attributes of age, size, vegetation structure, and

  15. Links between plant litter chemistry, species diversity, and below-ground ecosystem function

    OpenAIRE

    Meier, Courtney L.; Bowman, William D.

    2008-01-01

    Decomposition is a critical source of plant nutrients, and drives the largest flux of terrestrial C to the atmosphere. Decomposing soil organic matter typically contains litter from multiple plant species, yet we lack a mechanistic understanding of how species diversity influences decomposition processes. Here, we show that soil C and N cycling during decomposition are controlled by the composition and diversity of chemical compounds within plant litter mixtures, rather than by simple metrics...

  16. Social organization influences the exchange and species richness of medicinal plants in Amazonian homegardens.

    Science.gov (United States)

    2016-03-01

    Medicinal plants provide indigenous and peasant communities worldwide with means to meet their healthcare needs. Homegardens often act as medicine cabinets, providing easily accessible medicinal plants for household needs. Social structure and social exchanges have been proposed as factors influencing the species diversity that people maintain in their homegardens. Here, we assess the association between the exchange of medicinal knowledge and plant material and medicinal plant richness in homegardens. Using Tsimane' Amazonian homegardens as a case study, we explore whether social organization shapes exchanges of medicinal plant knowledge and medicinal plant material. We also use network centrality measures to evaluate people's location and performance in medicinal plant knowledge and plant material exchange networks. Our results suggest that social organization, specifically kinship and gender relations, influences medicinal plant exchange patterns significantly. Homegardens total and medicinal plant species richness are related to gardeners' centrality in the networks, whereby people with greater centrality maintain greater plant richness. Thus, together with agroecological conditions, social relations among gardeners and the culturally specific social structure seem to be important determinants of plant richness in homegardens. Understanding which factors pattern general species diversity in tropical homegardens, and medicinal plant diversity in particular, can help policy makers, health providers, and local communities to understand better how to promote and preserve medicinal plants in situ. Biocultural approaches that are also gender sensitive offer a culturally appropriate means to reduce the global and local loss of both biological and cultural diversity.

  17. Vascular Plant and Vertebrate Inventory of Tuzigoot National Monument

    Science.gov (United States)

    Powell, Brian F.; Albrecht, E.W.; Halvorson, William Lee; Schmidt, Cecilia A.; Anning, P.; Docherty, K.

    2005-01-01

    Executive Summary From 2002 to 2004, we surveyed for plants and vertebrates (amphibians, reptiles, birds, and mammals) at Tuzigoot National Monument (NM) and adjacent areas in Arizona. This was the first effort of its kind in the area and was part of a larger effort to inventory vascular plants and vertebrates in eight National Park Service units in Arizona and New Mexico. In addition to our own surveys, we also compiled a complete list of species that have been found by previous studies. We found 330 species, including 142 that had not previously been recorded at the monument (Table 1). We found 39 species of non-native plants, 11 non-native fishes, three non-native birds, and one non-native species each of amphibian and mammal. Based on our work and that of others, there have been 597 species of plants and vertebrates found at the monument. The bird community at the monument had the highest species richness of any national park unit in central and southern Arizona. We found all other taxa to have intermediate species richness compared to other park units in the region. This extraordinary species richness observed for birds, as well as for some other taxa, is due primarily to Tavasci Marsh and the Verde River, two critical sources of perennial water, which provide habitat for many regionally rare or uncommon species. The location of the monument at the northern edge of the Sonoran Desert and at the southern edge of the Mogollon Rim also plays an important role in determining the distribution and community composition of the plant and vertebrate communities. Based on our findings, we believe the high number of non-native species, especially fish and plants, should be of particular management concern. We detail other management challenges, most notably the rapid increase in housing and associated commercial development near the monument, which will continue to impact the plant and vertebrate communities. Based on our data and a review of past studies, we believe the

  18. Genetic variation for sensitivity to a thyme monoterpene in associated plant species.

    Science.gov (United States)

    Jensen, Catrine Grønberg; Ehlers, Bodil Kirstine

    2010-04-01

    Recent studies have shown that plant allelochemicals can have profound effects on the performance of associated species, such that plants with a history of co-existence with "chemical neighbour" plants perform better in their presence compared to naïve plants. This has cast new light on the complexity of plant-plant interactions and plant communities and has led to debates on whether plant communities are more co-evolved than traditionally thought. In order to determine whether plants may indeed evolve in response to other plants' allelochemicals it is crucial to determine the presence of genetic variation for performance under the influence of specific allelochemicals and show that natural selection indeed operates on this variation. We studied the effect of the monoterpene carvacrol-a dominant compound in the essential oil of Thymus pulegioides-on three associated plant species originating from sites where thyme is either present or absent. We found the presence of genetic variation in both naïve and experienced populations for performance under the influence of the allelochemical but the response varied among naïve and experienced plant. Plants from experienced populations performed better than naïve plants on carvacrol soil and contained significantly more seed families with an adaptive response to carvacrol than naïve populations. This suggests that the presence of T. pulegioides can act as a selective agent on associated species, by favouring genotypes which perform best in the presence of its allelochemicals. The response to the thyme allelochemical varied from negative to neutral to positive among the species. The different responses within a species suggest that plant-plant interactions can evolve; this has implications for community dynamics and stability.

  19. Use of plant woody species electrical potential for irrigation scheduling.

    Science.gov (United States)

    Ríos-Rojas, Liliana; Morales-Moraga, David; Alcalde, José A; Gurovich, Luis A

    2015-01-01

    The electrical response of plants to environmental stimuli can be measured and quantitatively related to the intensity of several stimulating sources, like temperature, solar radiation, soil water content, evapotranspiration rates, sap flow and dendrometric cycles. These relations can be used to assess the influence of different environmental situations on soil water availability to plants, defined as a steady state condition between leaf transpirative flow and soil water flow to plant roots. A restricted soil water flow due to soil dryness can trigger water stress in plants, if the atmospheric evaporative demand is high, causing partial stomata closure as a physiological response to avoid plant dehydration; water stressed and unstressed plants manifest a differential electrical response. Real time plant electrical response measurements can anticipate actions that prevent the plant reaching actual stress conditions, optimizing stomata gas exchange and photosynthetic rates. An electrophysiological sensor developed in this work, allows remote real-time recording information on plant electrical potential (EP) in the field, which is highly related to EP measurements obtained with a laboratory Keithley voltmeter sensor used in an highly controlled experimental setup. Our electrophysiological sensor is a wireless, autonomous devise, which transmits EP information via Internet to a data server. Using both types of sensors (EP electrodes with a Keithley voltmeter and the electrophysiological sensor), we measured in real time the electrical responses of Persea americana and Prunus domestica plants, to induced water deficits. The differential response for 2 scenarios: irrigation and water restriction is identified by a progressive change in slope on the daily maximal and minimal electric signal values in stressed plants, and a zero-slope for similar signals for well-watered plants. Results show a correspondence between measured signals obtained by our electrophysiological

  20. Alien roadside species more easily invade alpine than lowland plant communities in a subarctic mountain ecosystem.

    Directory of Open Access Journals (Sweden)

    Jonas J Lembrechts

    Full Text Available Effects of roads on plant communities are not well known in cold-climate mountain ecosystems, where road building and development are expected to increase in future decades. Knowledge of the sensitivity of mountain plant communities to disturbance by roads is however important for future conservation purposes. We investigate the effects of roads on species richness and composition, including the plant strategies that are most affected, along three elevational gradients in a subarctic mountain ecosystem. We also examine whether mountain roads promote the introduction and invasion of alien plant species from the lowlands to the alpine zone. Observations of plant community composition were made together with abiotic, biotic and anthropogenic factors in 60 T-shaped transects. Alpine plant communities reacted differently to road disturbances than their lowland counterparts. On high elevations, the roadside species composition was more similar to that of the local natural communities. Less competitive and ruderal species were present at high compared with lower elevation roadsides. While the effects of roads thus seem to be mitigated in the alpine environment for plant species in general, mountain plant communities are more invasible than lowland communities. More precisely, relatively more alien species present in the roadside were found to invade into the surrounding natural community at high compared to low elevations. We conclude that effects of roads and introduction of alien species in lowlands cannot simply be extrapolated to the alpine and subarctic environment.

  1. Alien roadside species more easily invade alpine than lowland plant communities in a subarctic mountain ecosystem.

    Science.gov (United States)

    Lembrechts, Jonas J; Milbau, Ann; Nijs, Ivan

    2014-01-01

    Effects of roads on plant communities are not well known in cold-climate mountain ecosystems, where road building and development are expected to increase in future decades. Knowledge of the sensitivity of mountain plant communities to disturbance by roads is however important for future conservation purposes. We investigate the effects of roads on species richness and composition, including the plant strategies that are most affected, along three elevational gradients in a subarctic mountain ecosystem. We also examine whether mountain roads promote the introduction and invasion of alien plant species from the lowlands to the alpine zone. Observations of plant community composition were made together with abiotic, biotic and anthropogenic factors in 60 T-shaped transects. Alpine plant communities reacted differently to road disturbances than their lowland counterparts. On high elevations, the roadside species composition was more similar to that of the local natural communities. Less competitive and ruderal species were present at high compared with lower elevation roadsides. While the effects of roads thus seem to be mitigated in the alpine environment for plant species in general, mountain plant communities are more invasible than lowland communities. More precisely, relatively more alien species present in the roadside were found to invade into the surrounding natural community at high compared to low elevations. We conclude that effects of roads and introduction of alien species in lowlands cannot simply be extrapolated to the alpine and subarctic environment.

  2. Links between plant litter chemistry, species diversity, and below-ground ecosystem function.

    Science.gov (United States)

    Meier, Courtney L; Bowman, William D

    2008-12-16

    Decomposition is a critical source of plant nutrients, and drives the largest flux of terrestrial C to the atmosphere. Decomposing soil organic matter typically contains litter from multiple plant species, yet we lack a mechanistic understanding of how species diversity influences decomposition processes. Here, we show that soil C and N cycling during decomposition are controlled by the composition and diversity of chemical compounds within plant litter mixtures, rather than by simple metrics of plant species diversity. We amended native soils with litter mixtures containing up to 4 alpine plant species, and we used 9 litter chemical traits to evaluate the chemical composition (i.e., the identity and quantity of compounds) and chemical diversity of the litter mixtures. The chemical composition of the litter mixtures was the strongest predictor of soil respiration, net N mineralization, and microbial biomass N. Soil respiration and net N mineralization rates were also significantly correlated with the chemical diversity of the litter mixtures. In contrast, soil C and N cycling rates were poorly correlated with plant species richness, and there was no relationship between species richness and the chemical diversity of the litter mixtures. These results indicate that the composition and diversity of chemical compounds in litter are potentially important functional traits affecting decomposition, and simple metrics like plant species richness may fail to capture variation in these traits. Litter chemical traits therefore provide a mechanistic link between organisms, species diversity, and key components of below-ground ecosystem function.

  3. The factors controlling species density in herbaceous plant communities: An assessment

    Science.gov (United States)

    Grace, J.B.

    1999-01-01

    This paper evaluates both the ideas and empirical evidence pertaining to the control of species density in herbaceous plant communities. While most theoretical discussions of species density have emphasized the importance of habitat productivity and disturbance regimes, many other factors (e.g. species pools, plant litter accumulation, plant morphology) have been proposed to be important. A review of literature presenting observations on the density of species in small plots (in the vicinity of a few square meters or less), as well as experimental studies, suggests several generalizations: (1) Available data are consistent with an underlying unimodal relationship between species density and total community biomass. While variance in species density is often poorly explained by predictor variables, there is strong evidence that high levels of community biomass are antagonistic to high species density. (2) Community biomass is just one of several factors affecting variations in species density. Multivariate analyses typically explain more than twice as much variance in species density as can be explained by community biomass alone. (3) Disturbance has important and sometimes complex effects on species density. In general, the evidence is consistent with the intermediate disturbance hypothesis but exceptions exist and effects can be complex. (4) Gradients in the species pool can have important influences on patterns of species density. Evidence is mounting that a considerable amount of the observed variability in species density within a landscape or region may result from environmental effects on the species pool. (5) Several additional factors deserve greater consideration, including time lags, species composition, plant morphology, plant density and soil microbial effects. Based on the available evidence, a conceptual model of the primary factors controlling species density is presented here. This model suggests that species density is controlled by the effects of

  4. Assessment of heavy metal tolerance in native plant species from soils contaminated with electroplating effluent.

    Science.gov (United States)

    Sainger, Poonam Ahlawat; Dhankhar, Rajesh; Sainger, Manish; Kaushik, Anubha; Singh, Rana Pratap

    2011-11-01

    Heavy metals concentrations of (Cr, Zn, Fe, Cu and Ni) were determined in plants and soils contaminated with electroplating industrial effluent. The ranges of total soil Cr, Zn, Fe, Cu and Ni concentrations were found to be 1443-3240, 1376-3112, 683-2228, 263-374 and 234-335 mg kg⁻¹, respectively. Metal accumulation, along with hyperaccumulative characteristics of the screened plants was investigated. Present study highlighted that metal accumulation in different plants varied with species, tissues and metals. Only one plant (Amaranthus viridis) accumulated Fe concentrations over 1000 mg kg⁻¹. On the basis of TF, eight plant species for Zn and Fe, three plant species for Cu and two plant species for Ni, could be used in phytoextraction technology. Although BAF of all plant species was lesser than one, these species exhibited high metal adaptability and could be considered as potential hyperaccumulators. Phytoremediation potential of these plants can be used to remediate metal contaminated soils, though further investigation is still needed. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. THRIPS SPECIES (INSECTA: THYSANOPTERA OF ORNAMENTAL PLANTS FROM THE PARKS AND GREENHOUSES OF ADP PITESTI

    Directory of Open Access Journals (Sweden)

    Daniela Bărbuceanu

    2012-04-01

    Full Text Available The observations carried-out in 2008/2010 to ornamental plants from parks and greenhouses of ADP Pitesti relieve 12 species of thrips. One species of them, Frankliniella occidentalis was identified in greenhouses on Rosa sp., Dianthus sp. and Zantedeschia sp. In parks, the thrips species belong to 12 species, dominated by Frankliniella intonsa. All of them are polypfagous and divided in two throphic levels: primary and secondary consumers. The thrips species are mentioned for the first time in Romania on this host plant. In greenhouses are necessary intensive chemical treatments and methods of cultural hygiene to limit the F. occidentalis populations.

  6. Species richness of vascular plants, bryophytes, and lichens along an altitudinal gradient in western Norway

    Science.gov (United States)

    Grytnes, John Arvid; Heegaard, Einar; Ihlen, Per G.

    2006-05-01

    Species richness patterns of ground-dwelling vascular plants, bryophytes, and lichens were compared along an altitudinal gradient (310-1135 m a.s.l.), in western Norway. Total species richness peaked at intermediate altitudes, vascular plant species richness peaked immediately above the forest limit (at 600-700 m a.s.l.), bryophyte species richness had no statistically significant trend, whereas lichen richness increased from the lowest point and up to the forest limit, with no trend above. It is proposed that the pattern in vascular plant species richness is enhanced by an ecotone effect. Bryophyte species richness responds to local scale factors whereas the lichen species richness may be responding to the shading from the forest trees.

  7. Biology and occurrence of Inga Busk species (Lepidoptera: Oecophoridae) on Cerrado host plants.

    Science.gov (United States)

    Diniz, Ivone R; Bernardes, Carolina; Rodovalho, Sheila; Morais, Helena C

    2007-01-01

    We sampled Inga Busk species caterpillars weekly in the cerrado on 15 plants of Diospyros burchellii Hern. (Ebenaceae) from January 2002 to December 2003, on 30 plants of Caryocar brasiliense (Caryocaraceae) from July 2003 to June 2004, and since 1991 on several other plant species. In total we found 15 species of Inga on cerrado host plants. Nine species were very rare, with only one to five adults reared. The other six species occurred throughout the year, with higher abundance during the dry season, from May to July, coinciding with overall peaks of caterpillar abundance in the cerrado. Caterpillars of the genus Inga build shelters by tying and lining two mature or old leaves with silk and frass, where they rest and develop (a common habit found in Oecophorinae). The final instar builds a special envelope inside the leaf shelter, where it will complete the larval stage and pupate. The species are very difficult to distinguish in the immature stages. External features were useful in identifying only four species: I. haemataula (Meyrick), I. phaecrossa (Meyrick), I. ancorata (Walsingham), and I. corystes (Meyrick). These four species are polyphagous and have wide geographical distributions. In this paper we provide information on the natural history and host plants of six Inga species common on cerrado host plants, for which there are no reports in the literature.

  8. Organic, integrated and conventional management in apple orchards: effect on plant species composition, richness and diversity

    Directory of Open Access Journals (Sweden)

    Zdeňka Lososová

    2011-01-01

    Full Text Available The study was conducted to assess the effect of conventional, integrated and organic management on differences in plant species composition, richness and diversity. The plants were studied in triads of orchards situated in three regions of the Czech Republic. Data about species occurrences were collected on 15 permanent plots in the tree rows and 15 plots between tree rows in each of the apple orchards during 2009. A total of 201 vascular plant species (127 native species, 65 archaeophytes, and 9 neophytes were found. Management type and also different regional conditions had a significant effect on plant species composition and on diversity parameters of orchard spontaneous vegetation. Species richness and species pool was significantly higher in the organic orchards than in the differently managed orchards. Management type had significant effect on proportions of archaeophytes, and also neophytes in apple orchards. The results showed that a change from conventional to integrated and organic management in apple orchards lead to higher plant species diversity and to changes in plant species composition.

  9. Phytochemicals of selected plant species of the Apocynaceae and Asclepiadaceae from Western Ghats, Tamil Nadu, India

    Science.gov (United States)

    A concern about the declining supply of petroleum products has led to a renewed interest in evaluating plant species as potential alternate sources of energy. Five species of the Apocynaceae and three species of the Asclepiadaceae from the Western Ghats were evaluated as alternative sources of energ...

  10. The new flora of the northeastern USA: quantifying introduced plant species occupancy in forest ecosystems

    Science.gov (United States)

    Bethany K. Schulz; Andrew N. Gray

    2013-01-01

    Introduced plant species have significant negative impacts in many ecosystems and are found in many forests around the world. Some factors linked to the distribution of introduced species include fragmentation and disturbance, native species richness, and climatic and physical conditions of the landscape. However, there are few data sources that enable the assessment...

  11. Plant–soil interactions in the expansion and native range of a poleward shifting plant species

    NARCIS (Netherlands)

    Van Grunsven, R.H.A.; Van der Putten, W.H.; Bezemer, T.M.; Berendse, F.; Veenendaal, E.M.

    2010-01-01

    Climate warming causes range shifts of many species toward higher latitudes and altitudes. However, range shifts of host species do not necessarily proceed at the same rates as those of their enemies and symbionts. Here, we examined how a range shifting plant species performs in soil from its

  12. Race to Displace: A Game to Model the Effects of Invasive Species on Plant Communities

    Science.gov (United States)

    Hopwood, Jennifer L.; Flowers, Susan K.; Seidler, Katie J.; Hopwood, Erica L.

    2013-01-01

    Invasive species are a substantial threat to biodiversity. Educating students about invasive species introduces fundamental concepts in biology, ecology, and environmental science. In the Race to Displace game, students assume the characteristics of select native or introduced plants and experience first hand the influences of species interactions…

  13. Introduced Terrestrial Species (Future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — These data represent predicted future potential distributions of terrestrial plants, animals, and pathogens non-native to the Middle-Atlantic region. These data are...

  14. Antimicrobial activity of some endemic plant species from Turkey

    African Journals Online (AJOL)

    SERVER

    2007-08-06

    Aug 6, 2007 ... Antibacterial and antifungal activity of Heracleum sphondylium subsp. arvinense. Afr. J. Biotechnol. 5: 1087-1089. Ertürk Ö (2006). Antibacterial and antifungal activity of ethanolic extracts from eleven spice plants. Biologia. 61: 275-278. Fazly Bazzaz BS, Haririzadeh G (2003). Screening of Iranian plants for.

  15. Susceptibility of Australian plant species to Phytophthora ramorum

    Science.gov (United States)

    Kylie Ireland; Daniel H& uuml; berli; Bernard Dell; Ian Smith; David Rizzo; Giles. Hardy

    2010-01-01

    Phytophthora ramorum is an invasive plant pathogen causing considerable and widespread damage in nurseries, gardens, and natural woodland ecosystems of the United States and Europe, and is classified as a Category 1 pest in Australia. It is of particular interest to Australian plant biosecurity as, like P. cinnamomi; it has...

  16. Plant Growth and Phosphorus Uptake of Three Riparian Grass Species

    Science.gov (United States)

    Riparian buffers can significantly reduce sediment-bound phosphorus (P) entering surface water, but control of dissolved P inputs is more challenging. Because plant roots remove P from soil solution, it follows that plant uptake will reduce dissolved P losses. We evaluated P uptake of smooth bromegr...

  17. Regional climate model downscaling may improve the prediction of alien plant species distributions

    Science.gov (United States)

    Liu, Shuyan; Liang, Xin-Zhong; Gao, Wei; Stohlgren, Thomas J.

    2014-12-01

    Distributions of invasive species are commonly predicted with species distribution models that build upon the statistical relationships between observed species presence data and climate data. We used field observations, climate station data, and Maximum Entropy species distribution models for 13 invasive plant species in the United States, and then compared the models with inputs from a General Circulation Model (hereafter GCM-based models) and a downscaled Regional Climate Model (hereafter, RCM-based models).We also compared species distributions based on either GCM-based or RCM-based models for the present (1990-1999) to the future (2046-2055). RCM-based species distribution models replicated observed distributions remarkably better than GCM-based models for all invasive species under the current climate. This was shown for the presence locations of the species, and by using four common statistical metrics to compare modeled distributions. For two widespread invasive taxa ( Bromus tectorum or cheatgrass, and Tamarix spp. or tamarisk), GCM-based models failed miserably to reproduce observed species distributions. In contrast, RCM-based species distribution models closely matched observations. Future species distributions may be significantly affected by using GCM-based inputs. Because invasive plants species often show high resilience and low rates of local extinction, RCM-based species distribution models may perform better than GCM-based species distribution models for planning containment programs for invasive species.

  18. An Ethnobotanical Survey on Fuel Wood and Timber plant Species ...

    African Journals Online (AJOL)

    Yomi

    2011-12-19

    Dec 19, 2011 ... 3Department of Botany, Post Graduate College Abbottabad, Pakistan. Accepted 17 March, 2011. A survey was conducted to explore the fuel wood species and timber producing species of Kaghan valleys, Pakistan. Consumption pattern and impact on the forest resources were also taken into consideration.

  19. An Ethnobotanical Survey on Fuel Wood and Timber plant Species ...

    African Journals Online (AJOL)

    A survey was conducted to explore the fuel wood species and timber producing species of Kaghan valleys, Pakistan. Consumption pattern and impact on the forest resources were also taken into consideration. A questionnaire was used as a survey instrument to obtain desired data. For this study, 10 villages were randomly ...

  20. Explaining the variation in impacts of non-native plants on local-scale species richness: the role of phylogenetic relatedness

    Czech Academy of Sciences Publication Activity Database

    Vila, M.; Rohr, R. P.; Espinar, J. L.; Hulme, P. E.; Pergl, Jan; Le Roux, J. J.; Schaffner, U.; Pyšek, Petr

    2015-01-01

    Roč. 24, č. 2 (2015), s. 139-146 ISSN 1466-822X R&D Projects: GA ČR(CZ) GAP505/11/1112; GA ČR(CZ) GAP504/11/1028 Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : biological invasions * impact * metaanalysis Subject RIV: EH - Ecology, Behaviour Impact factor: 5.840, year: 2015

  1. 75 FR 15454 - Endangered and Threatened Wildlife and Plants; 5-Year Status Reviews of 14 Southwestern Species

    Science.gov (United States)

    2010-03-29

    ...] Endangered and Threatened Wildlife and Plants; 5-Year Status Reviews of 14 Southwestern Species AGENCY: Fish... species or subspecies of fish, wildlife, or plant, and any distinct population segment of any species of... extinction throughout all or a significant portion of its range. C. Threatened species (T) means any species...

  2. 75 FR 55820 - Endangered and Threatened Wildlife and Plants; 5-Year Status Reviews of Seven Midwest Species

    Science.gov (United States)

    2010-09-14

    ...] Endangered and Threatened Wildlife and Plants; 5-Year Status Reviews of Seven Midwest Species AGENCY: Fish... CFR 424.02: (A) Species includes any species or subspecies of fish, wildlife, or plant, and any... species means any species that is in danger of extinction throughout all or a significant portion of its...

  3. Postglacial migration supplements climate in determining plant species ranges in Europe

    Science.gov (United States)

    Normand, Signe; Ricklefs, Robert E.; Skov, Flemming; Bladt, Jesper; Tackenberg, Oliver; Svenning, Jens-Christian

    2011-01-01

    The influence of dispersal limitation on species ranges remains controversial. Considering the dramatic impacts of the last glaciation in Europe, species might not have tracked climate changes through time and, as a consequence, their present-day ranges might be in disequilibrium with current climate. For 1016 European plant species, we assessed the relative importance of current climate and limited postglacial migration in determining species ranges using regression modelling and explanatory variables representing climate, and a novel species-specific hind-casting-based measure of accessibility to postglacial colonization. Climate was important for all species, while postglacial colonization also constrained the ranges of more than 50 per cent of the species. On average, climate explained five times more variation in species ranges than accessibility, but accessibility was the strongest determinant for one-sixth of the species. Accessibility was particularly important for species with limited long-distance dispersal ability, with southern glacial ranges, seed plants compared with ferns, and small-range species in southern Europe. In addition, accessibility explained one-third of the variation in species' disequilibrium with climate as measured by the realized/potential range size ratio computed with niche modelling. In conclusion, we show that although climate is the dominant broad-scale determinant of European plant species ranges, constrained dispersal plays an important supplementary role. PMID:21543356

  4. Impact of Non-Native Birds on Native Ecosystems: A Global Analysis.

    Science.gov (United States)

    Martin-Albarracin, Valeria L; Amico, Guillermo C; Simberloff, Daniel; Nuñez, Martin A

    2015-01-01

    Introduction and naturalization of non-native species is one of the most important threats to global biodiversity. Birds have been widely introduced worldwide, but their impacts on populations, communities, and ecosystems have not received as much attention as those of other groups. This work is a global synthesis of the impact of nonnative birds on native ecosystems to determine (1) what groups, impacts, and locations have been best studied; (2) which taxonomic groups and which impacts have greatest effects on ecosystems, (3) how important are bird impacts at the community and ecosystem levels, and (4) what are the known benefits of nonnative birds to natural ecosystems. We conducted an extensive literature search that yielded 148 articles covering 39 species belonging to 18 families -18% of all known naturalized species. Studies were classified according to where they were conducted: Africa, Asia, Australasia, Europe, North America, South America, Islands of the Indian, of the Pacific, and of the Atlantic Ocean. Seven types of impact on native ecosystems were evaluated: competition, disease transmission, chemical, physical, or structural impact on ecosystem, grazing/ herbivory/ browsing, hybridization, predation, and interaction with other non-native species. Hybridization and disease transmission were the most important impacts, affecting the population and community levels. Ecosystem-level impacts, such as structural and chemical impacts were detected. Seven species were found to have positive impacts aside from negative ones. We provide suggestions for future studies focused on mechanisms of impact, regions, and understudied taxonomic groups.

  5. A comparative study of AMF diversity in annual and perennial plant species from semiarid gypsum soils.

    Science.gov (United States)

    Alguacil, M. M.; Torrecillas, E.; Roldán, A.; Díaz, G.; Torres, P.

    2012-04-01

    The arbuscular mycorrhizal fungi (AMF) communities composition regulate plant interactions and determine the structure of plant communities. In this study we analysed the diversity of AMF in the roots of two perennial gypsophyte plant species, Herniaria fruticosa and Senecio auricula, and an annual herbaceous species, Bromus rubens, growing in a gypsum soil from a semiarid area. The objective was to determine whether perennial and annual host plants support different AMF communities in their roots and whether there are AMF species that might be indicators of specific functional plant roles in these ecosystems. The roots were analysed by nested PCR, cloning, sequencing of the ribosomal DNA small subunit region and phylogenetic analysis. Twenty AMF sequence types, belonging to the Glomus group A, Glomus group B, Diversisporaceae, Acaulosporaceae, Archaeosporaceae and Paraglomeraceae, were identified. Both gypsophyte perennial species had differing compositions of the AMF community and higher diversity when compared with the annual species, showing preferential selection by specific AMF sequences types. B. rubens did not show host specificity, sharing the full composition of its AMF community with both perennial plant species. Seasonal variations in the competitiveness of AM fungi could explain the observed differences in AMF community composition, but this is still a working hypothesis that requires the analysis of further data obtained from a higher number of both annual and perennial plant species in order to be fully tested.

  6. Nitrogen and protein contents in some aquatic plant species

    Directory of Open Access Journals (Sweden)

    Krystyna Bytniewska

    2015-01-01

    Full Text Available Nitrogen and protein contents in higher aquatic plants deriving from a natural habitat were determined. The following plants were examined: Spirodela polyrrhiza (L. Schleid., Elodea canadensis Rich., Riccia fluitans L. Total nitrogen and nitrogen of respective fractions were determined by the Kjeldahl method. Nitrogen compounds were fractionated according to Thimann et al. Protein was extracted after Fletcher and Osborne and fractionated after Osborne. It was found, that total protein content in the plants under examination constitutes 18 to 25%o of dry matter. Albumins and glutelins are the most abundant protein fractions.

  7. Cultural significance of medicinal plant families and species among Quechua farmers in Apillapampa, Bolivia.

    Science.gov (United States)

    Thomas, Evert; Vandebroek, Ina; Sanca, Sabino; Van Damme, Patrick

    2009-02-25

    Medicinal plant use was investigated in Apillapampa, a community of subsistence farmers located in the semi-arid Bolivian Andes. The main objectives were to identify the culturally most significant medicinal plant families and species in Apillapampa. A total of 341 medicinal plant species was inventoried during guided fieldtrips and transect sampling. Data on medicinal uses were obtained from fifteen local Quechua participants, eight of them being traditional healers. Contingency table and binomial analyses of medicinal plants used versus the total number of inventoried species per family showed that Solanaceae is significantly overused in traditional medicine, whereas Poaceae is underused. Also plants with a shrubby habitat are significantly overrepresented in the medicinal plant inventory, which most likely relates to their year-round availability to people as compared to most annual plants that disappear in the dry season. Our ranking of medicinal species according to cultural importance is based upon the Quality Use Agreement Value (QUAV) index we developed. This index takes into account (1) the average number of medicinal uses reported for each plant species by participants; (2) the perceived quality of those medicinal uses; and (3) participant consensus. According to the results, the QUAV index provides an easily derived and valid appraisal of a medicinal plant's cultural significance.

  8. Individual-based ant-plant networks: diurnal-nocturnal structure and species-area relationship.

    Directory of Open Access Journals (Sweden)

    Wesley Dáttilo

    Full Text Available Despite the importance and increasing knowledge of ecological networks, sampling effort and intrapopulation variation has been widely overlooked. Using continuous daily sampling of ants visiting three plant species in the Brazilian Neotropical savanna, we evaluated for the first time the topological structure over 24 h and species-area relationships (based on the number of extrafloral nectaries available in individual-based ant-plant networks. We observed that diurnal and nocturnal ant-plant networks exhibited the same pattern of interactions: a nested and non-modular pattern and an average level of network specialization. Despite the high similarity in the ants' composition between the two collection periods, ant species found in the central core of highly interacting species totally changed between diurnal and nocturnal sampling for all plant species. In other words, this "night-turnover" suggests that the ecological dynamics of these ant-plant interactions can be temporally partitioned (day and night at a small spatial scale. Thus, it is possible that in some cases processes shaping mutualistic networks formed by protective ants and plants may be underestimated by diurnal sampling alone. Moreover, we did not observe any effect of the number of extrafloral nectaries on ant richness and their foraging on such plants in any of the studied ant-plant networks. We hypothesize that competitively superior ants could monopolize individual plants and allow the coexistence of only a few other ant species, however, other alternative hypotheses are also discussed. Thus, sampling period and species-area relationship produces basic information that increases our confidence in how individual-based ant-plant networks are structured, and the need to consider nocturnal records in ant-plant network sampling design so as to decrease inappropriate inferences.

  9. Influences of Plant Species, Season and Location on Leaf Endophytic Bacterial Communities of Non-Cultivated Plants.

    Science.gov (United States)

    Ding, Tao; Melcher, Ulrich

    2016-01-01

    Bacteria are known to be associated endophytically with plants. Research on endophytic bacteria has identified their importance in food safety, agricultural production and phytoremediation. However, the diversity of endophytic bacterial communities and the forces that shape their compositions in non-cultivated plants are largely uncharacterized. In this study, we explored the diversity, community structure, and dynamics of endophytic bacteria in different plant species in the Tallgrass Prairie Preserve of northern Oklahoma, USA. High throughput sequencing of amplified segments of bacterial rDNA from 81 samples collected at four sampling times from five plant species at four locations identified 335 distinct OTUs at 97% sequence similarity, representing 16 phyla. Proteobacteria was the dominant phylum in the communities, followed by the phyla Bacteriodetes and Actinobacteria. Bacteria from four classes of Proteobacteria were detected with Alphaproteobacteria as the dominant class. Analysis of molecular variance revealed that host plant species and collecting date had significant influences on the compositions of the leaf endophytic bacterial communities. The proportion of Alphaproteobacteria was much higher in the communities from Asclepias viridis than from other plant species and differed from month to month. The most dominant bacterial groups identified in LDA Effect Size analysis showed host-specific patterns, indicating mutual selection between host plants and endophytic bacteria and that leaf endophytic bacterial compositions were dynamic, varying with the host plant's growing season in three distinct patterns. In summary, next generation sequencing has revealed variations in the taxonomic compositions of leaf endophytic bacterial communities dependent primarily on the nature of the plant host species.

  10. Influences of Plant Species, Season and Location on Leaf Endophytic Bacterial Communities of Non-Cultivated Plants.

    Directory of Open Access Journals (Sweden)

    Tao Ding

    Full Text Available Bacteria are known to be associated endophytically with plants. Research on endophytic bacteria has identified their importance in food safety, agricultural production and phytoremediation. However, the diversity of endophytic bacterial communities and the forces that shape their compositions in non-cultivated plants are largely uncharacterized. In this study, we explored the diversity, community structure, and dynamics of endophytic bacteria in different plant species in the Tallgrass Prairie Preserve of northern Oklahoma, USA. High throughput sequencing of amplified segments of bacterial rDNA from 81 samples collected at four sampling times from five plant species at four locations identified 335 distinct OTUs at 97% sequence similarity, representing 16 phyla. Proteobacteria was the dominant phylum in the communities, followed by the phyla Bacteriodetes and Actinobacteria. Bacteria from four classes of Proteobacteria were detected with Alphaproteobacteria as the dominant class. Analysis of molecular variance revealed that host plant species and collecting date had significant influences on the compositions of the leaf endophytic bacterial communities. The proportion of Alphaproteobacteria was much higher in the communities from Asclepias viridis than from other plant species and differed from month to month. The most dominant bacterial groups identified in LDA Effect Size analysis showed host-specific patterns, indicating mutual selection between host plants and endophytic bacteria and that leaf endophytic bacterial compositions were dynamic, varying with the host plant's growing season in three distinct patterns. In summary, next generation sequencing has revealed variations in the taxonomic compositions of leaf endophytic bacterial communities dependent primarily on the nature of the plant host species.

  11. Invasive clonal plant species have a greater root-foraging plasticity than non-invasive ones.

    Science.gov (United States)

    Keser, Lidewij H; Dawson, Wayne; Song, Yao-Bin; Yu, Fei-Hai; Fischer, Markus; Dong, Ming; van Kleunen, Mark

    2014-03-01

    Clonality is frequently positively correlated with plant invasiveness, but which aspects of clonality make some clonal species more invasive than others is not known. Due to their spreading growth form, clonal plants are likely to experience spatial heterogeneity in nutrient availability. Plasticity in allocation of biomass to clonal growth organs and roots may allow these plants to forage for high-nutrient patches. We investigated whether this foraging response is stronger in species that have become invasive than in species that have not. We used six confamilial pairs of native European clonal plant species differing in invasion success in the USA. We grew all species in large pots under homogeneous or heterogeneous nutrient conditions in a greenhouse, and compared their nutrient-foraging response and performance. Neither invasive nor non-invasive species showed significant foraging responses to heterogeneity in clonal growth organ biomass or in aboveground biomass of clonal offspring. Invasive species had, however, a greater positive foraging response in terms of root and belowground biomass than non-invasive species. Invasive species also produced more total biomass. Our results suggest that the ability for strong root foraging is among the characteristics promoting invasiveness in clonal plants.

  12. The performance of plant species in removing nutrients from ...

    African Journals Online (AJOL)

    2011-10-26

    Oct 26, 2011 ... but offered no explicit guidance about how these water quality targets might be achieved. ... the limited knowledge that exists about the performance of local plant ...... reuse: designing biofiltration systems for reliable treatment.

  13. Threatened plant species of the Nevada Test Site, Ash Meadows, central-southern Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Beatley, J.C.

    1977-04-01

    This report is a companion one to Endangered Plant Species of the Nevada Test Site, Ash Meadows, and Central-Southern Nevada (COO-2307-11) and deals with the threatened plant species of the same area. The species are those cited in the Federal Register, July 1, 1975, and include certain ones listed as occurring only in California or Arizona, but which occur also in central-southern Nevada. As with the earlier report, the purpose of this one is to record in detail the location of the past plant collections which constitute the sole or principal basis for defining the species' distributions and frequency of occurrence in southern Nye County, Nevada, and to recommend the area of the critical habitat where this is appropriate. Many of the species occur also in southern California, and for these the central-southern Nevada records are presented for consideration of the overall status of the species throughout its range.

  14. Individual species-area relationship of woody plant communities in a heterogeneous subtropical monsoon rainforest.

    Science.gov (United States)

    Tsai, Cheng-Han; Lin, Yi-Ching; Wiegand, Thorsten; Nakazawa, Takefumi; Su, Sheng-Hsin; Hsieh, Chih-Hao; Ding, Tzung-Su

    2015-01-01

    The spatial structure of species richness is often characterized by the species-area relationship (SAR). However, the SAR approach rarely considers the spatial variability of individual plants that arises from species interactions and species' habitat associations. Here, we explored how the interactions of individual plants of target species influence SAR patterns at a range of neighborhood distances. We analyzed the data of 113,988 woody plants of 110 species from the Fushan Forest Dynamics Plot (25 ha), northern Taiwan, which is a subtropical rainforest heavily influenced by typhoons. We classified 34 dominant species into 3 species types (i.e., accumulator, repeller, or no effect) by testing how the individual species-area relationship (i.e., statistics describing how neighborhood species richness changes around individuals) of target species departs (i.e., positively, negatively, or with no obvious trend) from a null model that accounts for habitat association. Deviation from the null model suggests that the net effect of species' interactions increases (accumulate) or decreases (repel) neighborhood species richness. We found that (i) accumulators were dominant at small interaction distances (30 m); (iii) repellers were rarely detected; and (iv) large-sized and abundant species tended to be accumulators. The findings suggest that positive species interactions have the potential to accumulate neighborhood species richness, particularly through size- and density-dependent mechanisms. We hypothesized that the frequently disturbed environment of this subtropical rainforest (e.g., typhoon-driven natural disturbances such as landslides, soil erosion, flooding, and windthrow) might create the spatial heterogeneity of species richness and promote positive species interactions.

  15. Identifying plant traits: a key aspect for suitable species selection in ecological restoration of semiarid slopes

    Science.gov (United States)

    Bochet, Esther; García-Fayos, Patricio

    2017-04-01

    In the context of ecological restoration, one of the greatest challenges for practitioners and scientists is to select suitable species for revegetation purposes. In semiarid environments where restoration projects often fail, little attention has been paid so far to the contribution of plant traits to species success. The objective of this study was to (1) identify plant traits associated with species success on four roadside situations along an erosion-productivity gradient, and (2) to provide an ecological framework for selecting suitable species on the basis of their morphological and functional traits, applied to semiarid environments. We analyzed the association of 10 different plant traits with species success of 296 species surveyed on the four roadside situations in a semiarid region (Valencia, Spain). Plant traits included general plant traits (longevity, woodiness) and more specific root-, seed- and leaf-related traits (root type, sprouting ability, seed mucilage, seed mass, seed susceptibility to removal, specific leaf area and leaf dry matter content). All of them were selected according to the prevailing limiting ecogeomorphological processes acting along the erosion-productivity gradient. We observed strong shifts along the erosion-productivity gradient in the traits associated to species success. At the harshest end of the gradient, the most intensely eroded and driest one, species success was mainly associated to seed resistance to removal by runoff and to resistance to drought. At the opposite end of the gradient, the most productive one, species success was associated to a competitive-ruderal plant strategy (herbaceous successful species with high specific leaf area and low leaf dry matter content). Our study provides an ecologically-based approach for selecting suitable native species on the basis or their morphological and functional traits and supports a differential trait-based selection of species as regards roadslope type and aspect. In

  16. Control of invasive plant species in created wetlands.

    Science.gov (United States)

    1994-01-01

    The Virginia Department of Transportation (VDOT) has been using a herbicide in the form of glyphosate for the control of unwanted species in created wetlands. Results with this particular herbicide have been somewhat mixed. It was requested that the ...

  17. Plant species' origin predicts dominance and response to nutrient enrichment and herbivores in global grasslands

    Science.gov (United States)

    Seabloom, Eric W.; Borer, Elizabeth T.; Buckley, Yvonne M.; Cleland, Elsa E.; Davies, Kendi F.; Firn, Jennifer; Harpole, W. Stanley; Hautier, Yann; Lind, Eric M.; MacDougall, Andrew S.; Orrock, John L.; Prober, Suzanne M.; Adler, Peter B.; Anderson, T. Michael; Bakker, Jonathan D.; Biederman, Lori A.; Blumenthal, Dana M.; Brown, Cynthia S.; Brudvig, Lars A.; Cadotte, Marc; Chu, Chengjin; Cottingham, Kathryn L.; Crawley, Michael J.; Damschen, Ellen I.; Dantonio, Carla M.; DeCrappeo, Nicole M.; Du, Guozhen; Fay, Philip A.; Frater, Paul; Gruner, Daniel S.; Hagenah, Nicole; Hector, Andy; Hillebrand, Helmut; Hofmockel, Kirsten S.; Humphries, Hope C.; Jin, Virginia L.; Kay, Adam; Kirkman, Kevin P.; Klein, Julia A.; Knops, Johannes M. H.; La Pierre, Kimberly J.; Ladwig, Laura; Lambrinos, John G.; Li, Qi; Li, Wei; Marushia, Robin; McCulley, Rebecca L.; Melbourne, Brett A.; Mitchell, Charles E.; Moore, Joslin L.; Morgan, John; Mortensen, Brent; O'Halloran, Lydia R.; Pyke, David A.; Risch, Anita C.; Sankaran, Mahesh; Schuetz, Martin; Simonsen, Anna; Smith, Melinda D.; Stevens, Carly J.; Sullivan, Lauren; Wolkovich, Elizabeth; Wragg, Peter D.; Wright, Justin; Yang, Louie

    2015-01-01

    Exotic species dominate many communities; however the functional significance of species' biogeographic origin remains highly contentious. This debate is fuelled in part by the lack of globally replicated, systematic data assessing the relationship between species provenance, function and response to perturbations. We examined the abundance of native and exotic plant species at 64 grasslands in 13 countries, and at a subset of the sites we experimentally tested native and exotic species responses to two fundamental drivers of invasion, mineral nutrient supplies and vertebrate herbivory. Exotic species are six times more likely to dominate communities than native species. Furthermore, while experimental nutrient addition increases the cover and richness of exotic species, nutrients decrease native diversity and cover. Native and exotic species also differ in their response to vertebrate consumer exclusion. These results suggest that species origin has functional significance, and that eutrophication will lead to increased exotic dominance in grasslands. PMID:26173623

  18. The importance of species phylogenetic relationships and species traits for the intensity of plant-soil feedback

    Czech Academy of Sciences Publication Activity Database

    Münzbergová, Zuzana; Šurinová, Mária

    2015-01-01

    Roč. 6, č. 11 (2015), s. 1-16 ISSN 2150-8925 R&D Projects: GA ČR(CZ) GA15-11635S Institutional support: RVO:67985939 Keywords : phylogenetic relationships * species traits * plant-soil feedback Subject RIV: EF - Botanics Impact factor: 2.287, year: 2015

  19. Modeling invasive alien plant species in river systems : Interaction with native ecosystem engineers and effects on hydro-morphodynamic processes

    NARCIS (Netherlands)

    van Oorschot, M.; Kleinhans, M. G.; Geerling, G.W.; Egger, G.; Leuven, R.S.E.W.; Middelkoop, H.

    2017-01-01

    Invasive alien plant species negatively impact native plant communities by out-competing species or changing abiotic and biotic conditions in their introduced range. River systems are especially vulnerable to biological invasions, because waterways can function as invasion corridors. Understanding

  20. Site fidelity by bees drives pollination facilitation in sequentially blooming plant species.

    Science.gov (United States)

    Ogilvie, Jane E; Thomson, James D

    2016-06-01

    Plant species can influence the pollination and reproductive success of coflowering neighbors that share pollinators. Because some individual pollinators habitually forage in particular areas, it is also possible that plant species could influence the pollination of neighbors that bloom later. When flowers of a preferred forage plant decline in an area, site-fidelity may cause individual flower feeders to stay in an area and switch plant species rather than search for preferred plants in a new location. A newly blooming plant species may quickly inherit a set of visitors from a prior plant species, and therefore experience higher pollination success than it would in an area where the first species never bloomed. To test this, we manipulated the placement and timing of two plant species, Delphinium barbeyi and later-blooming Gentiana parryi. We recorded the responses of individually marked bumble bee pollinators. About 63% of marked individuals returned repeatedly to the same areas to forage on Delphinium. When Delphinium was experimentally taken out of bloom, most of those site-faithful individuals (78%) stayed and switched to Gentiana. Consequently, Gentiana flowers received more visits in areas where Delphinium had previously flowered, compared to areas where Delphinium was still flowering or never occurred. Gentiana stigmas received more pollen in areas where Delphinium disappeared than where it never bloomed, indicating that Delphinium increases the pollination of Gentiana when they are separated in time. Overall, we show that individual bumble bees are often site-faithful, causing one plant species to increase the pollination of another even when separated in time, which is a novel mechanism of pollination facilitation.

  1. Habitat types on the Hanford Site: Wildlife and plant species of concern

    Energy Technology Data Exchange (ETDEWEB)

    Downs, J.L.; Rickard, W.H.; Brandt, C.A. [and others

    1993-12-01

    The objective of this report is to provide a comprehensive source of the best available information on Hanford Site sensitive and critical habitats and plants and animals of importance or special status. In this report, sensitive habitats include areas known to be used by threatened, endangered, or sensitive plant or animal species, wetlands, preserves and refuges, and other sensitive habitats outlined in the Hanford Site Baseline Risk Assessment Methodology. Potentially important species for risk assessment and species of special concern with regard to their status as threatened, endangered, or sensitive are described, and potential habitats for these species identified.

  2. Are the metabolomic responses to folivory of closely related plant species linked to macroevolutionary and plant-folivore coevolutionary processes?

    Energy Technology Data Exchange (ETDEWEB)

    Rivas-Ubach, Albert [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland Washington 99354 USA; CREAF, Cerdanyola del Vallès 08913 Catalonia Spain; Hódar, José A. [Grupo de Ecología Terrestre, Departamento de Biología Animal y Ecología, Facultad de Ciencias, Universidad de Granada, 18071 Granada Spain; Sardans, Jordi [CREAF, Cerdanyola del Vallès 08913 Catalonia Spain; CSIC, Global Ecology Unit CREAF-CEAB-CSIC-UAB, Cerdanyola del Vallès 08913 Catalonia Spain; Kyle, Jennifer E. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland Washington 99354 USA; Kim, Young-Mo [Biological Sciences Division, Pacific Northwest National Laboratory, Richland Washington 99354 USA; Oravec, Michal [Global Change Research Centre, Academy of Sciences of the Czech Republic, Bĕlidla 4a CZ-603 00 Brno Czech Republic; Urban, Otmar [Global Change Research Centre, Academy of Sciences of the Czech Republic, Bĕlidla 4a CZ-603 00 Brno Czech Republic; Guenther, Alex [Department of Earth System Science, University of California, Irvine California 92697 USA; Peñuelas, Josep [CREAF, Cerdanyola del Vallès 08913 Catalonia Spain; CSIC, Global Ecology Unit CREAF-CEAB-CSIC-UAB, Cerdanyola del Vallès 08913 Catalonia Spain

    2016-06-02

    The debate whether the coevolution of plants and insects or macroevolutionary processes (phylogeny) is the main driver determining the arsenal of molecular defensive compounds of plants remains unresolved. Attacks by herbivorous insects affect not only the composition of defensive compounds in plants but the entire metabolome (the set of molecular metabolites), including defensive compounds. Metabolomes are the final products of genotypes and are directly affected by macroevolutionary processes, so closely related species should have similar metabolomic compositions and may respond in similar ways to attacks by folivores. We analyzed the elemental compositions and metabolomes of needles from Pinus pinaster, P. nigra and P. sylvestris to determine if these closely related Pinus species with different coevolutionary histories with the caterpillars of the processionary moth respond similarly to attacks by this lepidopteran. All pines had different metabolomes and metabolic responses to herbivorous attack. The metabolomic variation among the pine species and the responses to folivory reflected their macroevolutionary relationships, with P. pinaster having the most divergent metabolome. The concentrations of phenolic metabolites were generally not higher in the attacked trees, which had lower concentrations of terpenes, suggesting that herbivores avoid individuals with high concentrations of terpenes. Our results suggest that macroevolutionary history plays important roles in the metabolomic responses of these pine species to folivory, but plant-insect coevolution probably constrains those responses. Combinations of different evolutionary factors and trade-offs are likely responsible for the different responses of each species to folivory, which is not necessarily exclusively linked to plant-insect coevolution.

  3. Rapid plant evolution in the presence of an introduced species alters community composition.

    Science.gov (United States)

    Smith, David Solance; Lau, Matthew K; Jacobs, Ryan; Monroy, Jenna A; Shuster, Stephen M; Whitham, Thomas G

    2015-10-01

    Because introduced species may strongly interact with native species and thus affect their fitness, it is important to examine how these interactions can cascade to have ecological and evolutionary consequences for whole communities. Here, we examine the interactions among introduced Rocky Mountain elk, Cervus canadensis nelsoni, a common native plant, Solidago velutina, and the diverse plant-associated community of arthropods. While introduced species are recognized as one of the biggest threats to native ecosystems, relatively few studies have investigated an evolutionary mechanism by which introduced species alter native communities. Here, we use a common garden design that addresses and supports two hypotheses. First, native S. velutina has rapidly evolved in the presence of introduced elk. We found that plants originating from sites with introduced elk flowered nearly 3 weeks before plants originating from sites without elk. Second, evolution of S. velutina results in a change to the plant-associated arthropod community. We found that plants originating from sites with introduced elk supported an arthropod community that had ~35 % fewer total individuals and a different species composition. Our results show that the impacts of introduced species can have both ecological and evolutionary consequences for strongly interacting species that subsequently cascade to affect a much larger community. Such evolutionary consequences are likely to be long-term and difficult to remediate.

  4. Comparative analysis of diosgenin in Dioscorea species and related medicinal plants by UPLC-DAD-MS.

    Science.gov (United States)

    Yi, Tao; Fan, Lan-Lan; Chen, Hong-Li; Zhu, Guo-Yuan; Suen, Hau-Man; Tang, Yi-Na; Zhu, Lin; Chu, Chu; Zhao, Zhong-Zhen; Chen, Hu-Biao

    2014-08-09

    Dioscorea is a genus of flowering plants, and some Dioscorea species are known and used as a source for the steroidal sapogenin diosgenin. To screen potential resource from Dioscorea species and related medicinal plants for diosgenin extraction, a rapid method to compare the contents of diosgenin in various plants is crucial. An ultra-performance liquid chromatography (UPLC) coupled with diode array detection (DAD) and electrospray ionization mass spectrometry (ESI-MS) method was developed for identification and determination of diosgenin in various plants. A comprehensive validation of the developed method was conducted. Twenty-four batches of plant samples from four Dioscorea species, one Smilax species and two Heterosmilax species were analyzed by using the developed method.The present method presented good sensitivity, precision and accuracy. Diosgenin was found in three Dioscorea species and one Heterosmilax species, namely D. zingiberensis, D. septemloba, D. collettii and H. yunnanensis. The method is suitable for the screening of diosgenin resources from plants. D. zingiberensis is an important resource for diosgenin harvesting.

  5. An invasion risk map for non-native aquatic macrophytes of the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Argantonio Rodríguez-Merino

    2017-05-01

    Full Text Available Freshwater systems are particularly susceptible to non-native organisms, owing to their high sensitivity to the impacts that are caused by these organisms. Species distribution models, which are based on both environmental and socio-economic variables, facilitate the identification of the most vulnerable areas for the spread of non-native species. We used MaxEnt to predict the potential distribution of 20 non-native aquatic macrophytes in the Iberian Peninsula. Some selected variables, such as the temperature seasonality and the precipitation in the driest quarter, highlight the importance of the climate on their distribution. Notably, the human influence in the territory appears as a key variable in the distribution of studied species. The model discriminated between favorable and unfavorable areas with high accuracy. We used the model to build an invasion risk map of aquatic macrophytes for the Iberian Peninsula that included results from 20 individual models. It showed that the most vulnerable areas are located near to the sea, the major rivers basins, and the high population density areas. These facts suggest the importance of the human impact on the colonization and distribution of non-native aquatic macrophytes in the Iberian Peninsula, and more precisely agricultural development during the Green Revolution at the end of the 70’s. Our work also emphasizes the utility of species distribution models for the prevention and management of biological invasions.

  6. Non-native gobies facilitate the transmission of Bucephalus polymorphus (Trematoda)

    Czech Academy of Sciences Publication Activity Database

    Ondračková, Markéta; Hudcová, Iveta; Dávidová, Martina; Adámek, Zdeněk; Kašný, M.; Jurajda, Pavel

    2015-01-01

    Roč. 8, č. 1 (2015), s. 382 ISSN 1756-3305 R&D Projects: GA ČR(CZ) GAP505/12/2569 Institutional support: RVO:68081766 Keywords : Bucephalus polymorphus * Complex life cycle * Goby * Infectivity * Intermediate host * Non-native species * Trematode Subject RIV: EH - Ecology, Behaviour Impact factor: 3.234, year: 2015

  7. Non-native fish introductions and the reversibility of amphibian declines in the Sierra Nevada

    Science.gov (United States)

    Roland A. Knapp

    2004-01-01

    Amphibians are declining worldwide for a variety of reasons, including habitat alteration, introduction of non-native species, disease, climate change, and environmental contaminants. Amphibians often play important roles in structuring ecosystems, and, as a result, amphibian population declines or extinctions are likely to affect other trophic levels (Matthews and...

  8. Spatial Autocorrelation Patterns of Understory Plant Species in a Subtropical Rainforest at Lanjenchi, Southern Taiwan

    Directory of Open Access Journals (Sweden)

    Su-Wei Fan

    2010-06-01

    Full Text Available Many studies described relationships between plant species and intrinsic or exogenous factors, but few quantified spatial scales of species patterns. In this study, quantitative methods were used to explore the spatial scale of understory species (including resident and transient species, in order to identify the influential factors of species distribution. Resident species (including herbaceous species, climbers and tree ferns < 1 m high were investigated on seven transects, each 5-meter wide and 300-meter long, at Lanjenchi plot in Nanjenshan Reserve, southern Taiwan. Transient species (seedling of canopy, subcanopy and shrub species < 1 cm diameter at breast height were censused in three of the seven transects. The herb coverage and seedling abundance were calculated for each 5 × 5 m quadrat along the transects, and Moran’s I and Galiano’s new local variance (NLV indices were then used to identify the spatial scale of autocorrelation for each species. Patterns of species abundance of understory layer varied among species at fine scale within 50 meters. Resident species showed a higher proportion of significant autocorrelation than the transient species. Species with large size or prolonged fronds or stems tended to show larger scales in autocorrelation. However, dispersal syndromes and fruit types did not relate to any species’ spatial patterns. Several species showed a significant autocorrelation at a 180-meter class which happened to correspond to the local replicates of topographical features in hilltops. The spatial patterns of understory species at Lanjenchi plot are mainly influenced by species’ intrinsic traits and topographical characteristics.

  9. Plant species from coal mine overburden dumping site in Satui, South Kalimantan, Indonesia

    Directory of Open Access Journals (Sweden)

    Vivi Novianti

    2017-07-01

    Full Text Available Coal mine overburden (OB materials were nutrient-poor, loosely adhered particles of shale, stones, boulders, and cobbles, also contained elevated concentration of trace metals. This condition cause OB substrate did not support plants growth. However, there were certain species that able to grow on overburden dumping site. This investigation sought to identify plants species that presence on coal mine overburden. The research was conducted on opencast coal mine OB dumping site in Satui, South Kalimantan. Vegetation sampling was carried out on six different ages of coal mine OB dumps (7, 10, 11, 42, 59 and 64 month using line transect. Species identification used information from local people, AMDAL report of PT Arutmin Indonesia-Satui mine project, and website. There were 123 plant species, consisted of 79 herbs (Cyperaceae, Poaceae and Asteraceae, 10 lianes, bryophyte, 9 ferns, 10 shrubs, and 14 trees. A number of Poaceae, i.e., Paspalumconjugatum, Paspalumdilatatum, and Echinochloacolona generally present among the stones, boulders, and cobbles. While Cyperaceae such as Fimbristylis miliaceae, Cyperus javanicus, Rhyncospora corymbosa and Scleria sumatrensis most often foundinand around thebasin/pond with its smooth and humid substrate characteristics. Certain species of shrubs and trees present on the 7 month OB dumping site. They wereChromolaena odorata, Clibadium surinamense, Melastoma malabathricum, Trema micrantha, and Solanum torvum (Shrubs, Ochroma pyramidale and Homalanthus populifolius (trees. This plant species could be used for accelerating primary succession purpose on coal mine overburden dumping site. Nevertheless, species selection was needed to avoid planting invasive species.

  10. Leaf gas exchange and water status responses of a native and non-native grass to precipitation across contrasting soil surfaces in the Sonoran Desert.

    Science.gov (United States)

    Ignace, Danielle D; Huxman, Travis E; Weltzin, Jake F; Williams, David G

    2007-06-01

    Arid and semi-arid ecosystems of the southwestern US are undergoing changes in vegetation composition and are predicted to experience shifts in climate. To understand implications of these current and predicted changes, we conducted a precipitation manipulation experiment on the Santa Rita Experimental Range in southeastern Arizona. The objectives of our study were to determine how soil surface and seasonal timing of rainfall events mediate the dynamics of leaf-level photosynthesis and plant water status of a native and non-native grass species in response to precipitation pulse events. We followed a simulated precipitation event (pulse) that occurred prior to the onset of the North American monsoon (in June) and at the peak of the monsoon (in August) for 2002 and 2003. We measured responses of pre-dawn water potential, photosynthetic rate, and stomatal conductance of native (Heteropogon contortus) and non-native (Eragrostis lehmanniana) C(4) bunchgrasses on sandy and clay-rich soil surfaces. Soil surface did not always amplify differences in plant response to a pulse event. A June pulse event lead to an increase in plant water status and photosynthesis. Whereas the August pulse did not lead to an increase in plant water status and photosynthesis, due to favorable soil moisture conditions facilitating high plant performance during this period. E. lehmanniana did not demonstrate heightened photosynthetic performance over the native species in response to pulses across both soil surfaces. Overall accumulated leaf-level CO(2) response to a pulse event was dependent on antecedent soil moisture during the August pulse event, but not during the June pulse event. This work highlights the need to understand how desert species respond to pulse events across contrasting soil surfaces in water-limited systems that are predicted to experience changes in climate.

  11. Handbook of plant cell culture. Volume 2. Crop species

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, W.R.; Evans, D.A.; Ammirato, P.V.; Yamada, Y. (eds.)

    1984-01-01

    In this volume the state-of-the-art plant cell culture techniques described in the first volume are applied to several agricultural and horticultural crops. In 21 chapters, they include maize, oats, wheat, beans, red clover and other forage legumes, asparagus, celery, cassava, sweet potato, banana, pawpaw, apple, grapes, conifers, date palm, rubber, sugarcane and tobacco. Each chapter contains (1) detailed protocols to serve as the foundation for current research, (2) a critical review of the literature, and (3) in-depth evaluations of the potential shown by plant cell culture for crop improvement. The history and economic importance of each crop are discussed. This volume also includes an essay, ''Oil from plants'', by M. Calvin.

  12. Activities of arginine and ornithine decarboxylases in various plant species.

    Science.gov (United States)

    Birecka, H; Bitonti, A J; McCann, P P

    1985-10-01

    In extracts from the youngest leaves of Avena sativa, Hordeum vulgare, Zea Mays, Pisum sativum, Phaseolus vulgaris, Lactuca sativa, and four pyrrolizidine alkaloid-bearing species of Heliotropium, the activities of ornithine decarboxylase, close to V(max), ranged between traces and 1.5 nanomoles per hour per gram fresh weight when based on putrescine formed during incubation with labeled ornithine. The arginine decarboxylase activities in the same extracts ranged between 8 and 8000 nanomoles per hour per gram fresh weight being lowest in the borages and highest in oat and barley. alpha-Difluoromethylornithine and alpha-difluoromethylarginine inhibited ornithine and arginine decarboxylases, respectively, in all species. Agmatine, putrescine, spermidine, and spermine were found in all, diaminopropane in eight, and cadaverine in three species.No correlation was observed between arginine or ornithine decarboxylase level and the levels of total polyamines. The in vitro decarboxylase activities found in the borages cannot explain the high accumulation of putrescine-derived pyrrolizidines in their youngest leaves if the pyrrolizidines are produced in situ from arginine and/or ornithine as precursors; other possibilities are discussed.In assays of ornithine decarboxylase, an interference of decarboxylation not due to this enzyme was observed in extracts from all species. In arginine decarboxylase assays, the interfering decarboxylation as well as the interference of arginase were apparent in two species. Addition of aminoguanidine was needed to suppress oxidative degradation of putrescine and agmatine during incubation of extracts from pea, bean, lettuce, Heliotropium angiospermum, and Heliotropium indicum.

  13. Plant species diversity affects infiltration capacity in an experimental grassland through changes in soil properties

    NARCIS (Netherlands)

    Fischer, C.; Tischer, J.; Roscher, C.; Eisenhauer, N.; Ravenek, J.; Gleixner, G.; Attinger, S.; Jensen, B.; Kroon, de H.; Mommer, L.; Scheu, S.; Hildebrandt, A.

    2015-01-01

    Background and aims Soil hydraulic properties drive water distribution and availability in soil. There exists limited knowledge of how plant species diversity might influence soil hydraulic properties. Methods We quantified the change in infiltration capacity affected by soil structural variables

  14. 78 FR 32013 - Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for 38 Species...

    Science.gov (United States)

    2013-05-28

    ... potential for destruction of plants due their proximity to a popular hiking and jeep trail; and habitat... restoration of ecosystem functionality for the recovery of each species, and provide conservation benefits for...

  15. Threatened plant species in the river ports of Central Europe: a potential for nature conservation

    Czech Academy of Sciences Publication Activity Database

    Jehlík, V.; Dostálek, J.; Frantík, Tomáš

    2016-01-01

    Roč. 19, č. 2 (2016), s. 999-1012 ISSN 1083-8155 Institutional support: RVO:67985939 Keywords : Central Europe * plant species richness * waterway Subject RIV: EH - Ecology, Behaviour Impact factor: 1.970, year: 2016

  16. Distribution of the invasive plant species Heracleum sosnowskyi Manden. in the Komi Republic (Russia).

    Science.gov (United States)

    Chadin, Ivan; Dalke, Igor; Zakhozhiy, Ilya; Malyshev, Ruslan; Madi, Elena; Olga Kuzivanova; Kirillov, Dmitrii; Elsakov, Vladimir

    2017-01-01

    Occurrences of the invasive plant species Heracleum sosnowskyi Manden. in the Komi Republic (northeastern part of European Russia) were recorded and published in the Global Biodiversity Information Facility (GBIF http://www.gbif.org) using the RIVR information system (http://ib.komisc.ru/add/rivr/en). RIVR stands for "Rasprostranenie Invasionnyh Vidov Rastenij" [Occurrence of Invasion Plant Species]. This citizen science project aims at collecting occurrence data about invasive plant species with the help of citizen scientists. Information can be added by any user after a simple registration (concept) process. However, the data published in GBIF are provided only by professional scientists. The total study area is approximately 19,000 km 2 . The GBIF resource contains 10894 Heracleum sosnowskyi occurrence points, each with their geographical coordinates and photographs of the plants in the locus of growth. The preliminary results of species distribution modelling on the territory of European North-East Russia presented.

  17. Are trade-offs among species' ecological interactions scale dependent? A test using pitcher-plant inquiline species.

    Science.gov (United States)

    Kneitel, Jamie M

    2012-01-01

    Trade-offs among species' ecological interactions is a pervasive explanation for species coexistence. The traits associated with trade-offs are typically measured to mechanistically explain species coexistence at a single spatial scale. However, species potentially interact at multiple scales and this may be reflected in the traits among coexisting species. I quantified species' ecological traits associated with the trade-offs expected at both local (competitive ability and predator tolerance) and regional (competitive ability and colonization rate) community scales. The most common species (four protozoa and a rotifer) from the middle trophic level of a pitcher plant (Sarracenia purpurea) inquiline community were used to link species traits to previously observed patterns of species diversity and abundance. Traits associated with trade-offs (competitive ability, predator tolerance, and colonization rate) and other ecological traits (size, growth rate, and carrying capacity) were measured for each of the focal species. Traits were correlated with one another with a negative relationship indicative of a trade-off. Protozoan and rotifer species exhibited a negative relationship between competitive ability and predator tolerance, indicative of coexistence at the local community scale. There was no relationship between competitive ability and colonization rate. Size, growth rate, and carrying capacity were correlated with each other and the trade-off traits: Size was related to both competitive ability and predator tolerance, but growth rate and carrying capacity were correlated with predator tolerance. When partial correlations were conducted controlling for size, growth rate and carrying capacity, the trade-offs largely disappeared. These results imply that body size is the trait that provides the basis for ecological interactions and trade-offs. Altogether, this study showed that the examination of species' traits in the context of coexistence at different scales

  18. Tree-Dwelling Ants: Contrasting Two Brazilian Cerrado Plant Species without Extrafloral Nectaries

    Directory of Open Access Journals (Sweden)

    Jonas Maravalhas

    2012-01-01

    Full Text Available Ants dominate vegetation stratum, exploiting resources like extrafloral nectaries (EFNs and insect honeydew. These interactions are frequent in Brazilian cerrado and are well known, but few studies compare ant fauna and explored resources between plant species. We surveyed two cerrado plants without EFNs, Roupala montana (found on preserved environments of our study area and Solanum lycocarpum (disturbed ones. Ants were collected and identified, and resources on each plant noted. Ant frequency and richness were higher on R. montana (67%; 35 spp than S. lycocarpum (52%; 26, the occurrence of the common ant species varied between them, and similarity was low. Resources were explored mainly by Camponotus crassus and consisted of scale insects, aphids, and floral nectaries on R. montana and two treehopper species on S. lycocarpum. Ants have a high diversity on cerrado plants, exploring liquid and prey-based resources that vary in time and space and affect their presence on plants.

  19. Mapping plant species ranges in the Hawaiian Islands: developing a methodology and associated GIS layers

    Science.gov (United States)

    Price, Jonathan P.; Jacobi, James D.; Gon, Samuel M.; Matsuwaki, Dwight; Mehrhoff, Loyal; Wagner, Warren; Lucas, Matthew; Rowe, Barbara

    2012-01-01

    This report documents a methodology for projecting the geographic ranges of plant species in the Hawaiian Islands. The methodology consists primarily of the creation of several geographic information system (GIS) data layers depicting attributes related to the geographic ranges of plant species. The most important spatial-data layer generated here is an objectively defined classification of climate as it pertains to the distribution of plant species. By examining previous zonal-vegetation classifications in light of spatially detailed climate data, broad zones of climate relevant to contemporary concepts of vegetation in the Hawaiian Islands can be explicitly defined. Other spatial-data layers presented here include the following: substrate age, as large areas of the island of Hawai'i, in particular, are covered by very young lava flows inimical to the growth of many plant species; biogeographic regions of the larger islands that are composites of multiple volcanoes, as many of their species are restricted to a given topographically isolated mountain or a specified group of them; and human impact, which can reduce the range of many species relative to where they formerly were found. Other factors influencing the geographic ranges of species that are discussed here but not developed further, owing to limitations in rendering them spatially, include topography, soils, and disturbance. A method is described for analyzing these layers in a GIS, in conjunction with a database of species distributions, to project the ranges of plant species, which include both the potential range prior to human disturbance and the projected present range. Examples of range maps for several species are given as case studies that demonstrate different spatial characteristics of range. Several potential applications of species-range maps are discussed, including facilitating field surveys, informing restoration efforts, studying range size and rarity, studying biodiversity, managing

  20. Competitive interactions between native and invasive exotic plant species are altered under elevated carbon dioxide.

    Science.gov (United States)

    Manea, Anthony; Leishman, Michelle R

    2011-03-01

    We hypothesized that the greater competitive ability of invasive exotic plants relative to native plants would increase under elevated CO(2) because they typically have traits that confer the ability for fast growth when resources are not limiting and thus are likely to be more responsive to elevated CO(2). A series of competition experiments under ambient and elevated CO(2) glasshouse conditions were conducted to determine an index of relative competition intensity for 14 native-invasive exotic species-pairs. Traits including specific leaf area, leaf mass ratio, leaf area ratio, relative growth rate, net assimilation rate and root weight ratio were measured. Competitive rankings within species-pairs were not affected by CO(2) concentration: invasive exotic species were more competitive in 9 of the 14 species-pairs and native species were more competitive in the remaining 5 species-pairs, regardless of CO(2) concentration. However, there was a significant interaction between plant type and CO(2) treatment due to reduced competitive response of native species under elevated compared with ambient CO(2) conditions. Native species had significantly lower specific leaf area and leaf area ratio under elevated compared with ambient CO(2). We also compared traits of more-competitive with less-competitive species, regardless of plant type, under both CO(2) treatments. More-competitive species had smaller leaf weight ratio and leaf area ratio, and larger relative growth rate and net assimilation rate under both ambient and elevated CO(2) conditions. These results suggest that growth and allocation traits can be useful predictors of the outcome of competitive interactions under both ambient and elevated CO(2) conditions. Under predicted future atmospheric CO(2) conditions, competitive rankings among species may not change substantially, but the relative success of invasive exotic species may be increased. Thus, under future atmospheric CO(2) conditions, the ecological and

  1. In vitro propagation of the elite species plant Pluchea lanceolata ...

    African Journals Online (AJOL)

    SAM

    2014-06-18

    Jun 18, 2014 ... An effective in vitro regeneration protocol was developed from nodal segment of Pluchea lanceolata. (DC.) Oliver. & Hiern, a medicinally important plant used in ayurvedic system of medicine for curing diseases similar to rheumatoid arthritis. Nodal segments were cultured in MS medium supplemented.

  2. Plant species responses to oil degradation and toxicity reduction in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-01-05

    Jan 5, 2009 ... contaminated soil and sediment is an emerging techno- logy that promises effective and inexpensive clean up of certain hazardous wastes (Simeon 1993; Nwoko, 1995). Some of these processes occurs within the plants and involves the degradation or breakdown of organic and inorganic contaminants ...

  3. In vitro propagation of the elite species plant Pluchea lanceolata ...

    African Journals Online (AJOL)

    An effective in vitro regeneration protocol was developed from nodal segment of Pluchea lanceolata (DC.) Oliver. & Hiern, a medicinally important plant used in ayurvedic system of medicine for curing diseases similar to rheumatoid arthritis. Nodal segments were cultured in MS medium supplemented with auxin and ...

  4. Tritrophic interactions in wild and cultivated brassicaceous plant species

    NARCIS (Netherlands)

    Gols, R.

    2008-01-01

    Plants have evolved a range of defence traits that prevent or reduce attack by insect herbivores. Direct defence traits hamper or reduce the performance and behaviour of the herbivores, whereas indirect defence promote the efficiency of natural enemies to attack the herbivores. Here, I focused on

  5. Specific plant induced biofilm formation in Methylobacterium species

    Science.gov (United States)

    Rossetto, Priscilla B.; Dourado, Manuella N.; Quecine, Maria C.; Andreote, Fernando D.; Araújo, Welington L.; Azevedo, João L.; Pizzirani-Kleiner, Aline A.

    2011-01-01

    Two endophytic strains of Methylobacterium spp. were used to evaluate biofilm formation on sugarcane roots and on inert wooden sticks. Results show that biofilm formation is variable and that plant surface and possibly root exudates have a role in Methylobacterium spp. host recognition, biofilm formation and successful colonization as endophytes. PMID:24031703

  6. A Rose by Any Other Name: Plant Identification Knowledge & Socio-Demographics.

    Directory of Open Access Journals (Sweden)

    Beth S Robinson

    Full Text Available Concern has been expressed over societal losses of plant species identification skills. These losses have potential implications for engagement with conservation issues, gaining human wellbeing benefits from biodiversity (such as those resulting from nature-based recreational activities, and early warning of the spread of problematic species. However, understanding of the prevailing level of species identification skills, and of its key drivers, remains poor. Here, we explore socio-demographic factors influencing plant identification knowledge and ability to classify plants as native or non-native, employing a novel method of using real physical plants, rather than photographs or illustrations. We conducted face-to-face surveys at three different sites chosen to capture respondents with a range of socio-demographic circumstances, in Cornwall, UK. We found that survey participants correctly identified c.60% of common plant species, were significantly worse at naming non-native than native plants, and that less than 20% of people recognised Japanese knotweed Fallopia japonica, which is a widespread high profile invasive non-native in the study region. Success at naming plants was higher if participants were female, a member of at least one environmental, conservation or gardening organisation, in an older age group (than the base category of 18-29 years, or a resident (rather than visitor of the study area. Understanding patterns of variation in plant identification knowledge can inform the development of education and engagement strategies, for example, by targeting sectors of society where knowledge is lowest. Furthermore, greater understanding of general levels of identification of problematic invasive non-native plants can guide awareness and education campaigns to mitigate their impacts.

  7. Endangered plant species of the Nevada Test Site, Ash Meadows, and Central-Southern Nevada

    International Nuclear Information System (INIS)

    Beatley, J.C.

    1977-02-01

    A total of 15 vascular plant taxa, currently appearing on the Endangered Species list, occur in southern Nye County, Nevada, and/or adjacent Inyo County, California. It is the purpose of this report to record in detail the locations of the plant collections upon which the distributions are based, and other information relevant to their status as Endangered Species, and to recommend the areas to be designated critical habitats

  8. Drag forces of common plant species in temperate streams: consequences of morphology, velocity and biomass

    DEFF Research Database (Denmark)

    Jensen, Kaj Sand

    2008-01-01

    Swift flow in streams may physically influence the morphology and distribution of plants. I quantified drag as a function of velocity, biomass and their interaction on the trailing canopy of seven European stream species in an experimental flume and evaluated its importance for species distributi...... than an uneven distribution with the same biomass confined to dense patches surrounded by open flow channels. Thus, management strategies to ensure a patchy plants distribution should be suitable for combining agricultural drainage and ecological stream quality....

  9. Endangered plant species of the Nevada Test Site, Ash Meadows, and Central-Southern Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Beatley, J.C.

    1977-02-01

    A total of 15 vascular plant taxa, currently appearing on the Endangered Species list, occur in southern Nye County, Nevada, and/or adjacent Inyo County, California. It is the purpose of this report to record in detail the locations of the plant collections upon which the distributions are based, and other information relevant to their status as Endangered Species, and to recommend the areas to be designated critical habitats.

  10. The plant economics spectrum is structured by leaf habits and growth forms across subtropical species.

    Science.gov (United States)

    Zhao, Yan-Tao; Ali, Arshad; Yan, En-Rong

    2017-02-01

    The plant economics spectrum that integrates the combination of leaf and wood syndromes provides a useful framework for the examination of species strategies at the whole-plant level. However, it remains unclear how species that differ in leaf habits and growth forms are integrated within the plant economics spectrum in subtropical forests. We measured five leaf and six wood traits across 58 subtropical plant species, which represented two leaf habits (evergreen vs deciduous) and two growth forms (tree vs shrub) in eastern China. Principal component analysis (PCA) was employed separately to construct the leaf (LES), wood (WES) and whole-plant (WPES) economics spectra. Leaf and wood traits are highly intra- and intercorrelated, thus defining not only the LES and WES, but also a WPES. Multi-trait variations in PCAs revealed that the traits which were representative of the acquisitive strategy, i.e., cheap tissue investment and rapid returns on that investment, were clustered at one end, while traits that represented the conservative strategy, i.e., expensive tissue investment and slower returns, were clustered at other end in each of the axes of the leaf and wood syndromes (PC1-axis) and the plant height strategy (PC2-axis). The local WPES, LES and WES were tightly correlated with each other. Evergreens shaped the conservative side, while deciduous species structured the acquisitive side of the WPES and LES. With respect to plant height strategies, trees formulated the acquisitive side and shrub species made up the conservative side of the WPES, LES and WES. In conclusion, our results suggested that the LES and WES were coordinated to a WPES for subtropical species. The finding of this local spectrum of plant form and function would be beneficial for modeling nutrient fluxes and species compositions in the changing climate, but also for understanding species strategies in an evolutionary context. © The Author 2016. Published by Oxford University Press. All rights

  11. Removal of the pharmaceuticals ibuprofen and iohexol by four wetland plant species in hydroponic culture: plant uptake and microbial degradation.

    Science.gov (United States)

    Zhang, Yang; Lv, Tao; Carvalho, Pedro N; Arias, Carlos A; Chen, Zhanghe; Brix, Hans

    2016-02-01

    We aimed at assessing the effects of four wetland plant species commonly used in constructed wetland systems: Typha, Phragmites, Iris and Juncus for removing ibuprofen (IBU) and iohexol (IOH) from spiked culture solution and exploring the mechanisms responsible for the removal. IBU was nearly completely removed by all plant species during the 24-day experiment, whereas the IOH removal varied between 13 and 80 %. Typha and Phragmites were the most efficient in removing IBU and IOH, respectively, with first-order removal rate constants of 0.38 and 0.06 day(-1), respectively. The pharmaceuticals were taken up by the roots and translocated to the aerial tissues. However, at the end of the experiment, plant accumulation constituted only up to 1.1 and 5.7 % of the amount of IBU and IOH spiked initially. The data suggest that the plants mainly function by facilitating pharmaceutical degradation in the rhizosphere through release of root exudates.

  12. The assessment of invasive alien plant species removal programs ...

    African Journals Online (AJOL)

    Yusuf Adam

    a School of Agricultural, Earth and Environmental Sciences, University of ... variation of an environment due to localised extinction of endemic species. ... the abundance and impact of IAPs is still increasing (Müllerová et al., 2013). ... One of issues related to satellite image acquisition is cloud cover (Kerr & Ostrovsky, 2003).

  13. The assessment of invasive alien plant species removal programs ...

    African Journals Online (AJOL)

    Yusuf Adam

    Yusuf Adama, Njoya S Ngetara, Syd Ramdhanib a School of Agricultural, Earth and Environmental Sciences, University of KwaZulu-Natal, Howard ... Shaanker, 2013). These species affect human health, agriculture, forestry and biodiversity .... 2.2 Field data collection and image processing. Field data for the classification of ...

  14. Research Note Impacts of mine dump pollution on plant species ...

    African Journals Online (AJOL)

    Effects of mine dump pollution on semiarid savanna vegetation were investigated in Kombat, Namibia. Vegetation structure, species richness, composition and diversity were compared between polluted and control sites. Concentrations of arsenic, chromium, copper, lead and zinc in soils were significantly higher closer to a ...

  15. Growth responses to ozone in plant species from wetlands

    NARCIS (Netherlands)

    Franzaring, J.H.; Tonneijck, A.E.G.; Kooijman, A.W.N.; Dueck, Th.A.

    2000-01-01

    Ten wet grassland species were fumigated with four concentrations of ozone (charcoal-filtered air, non-filtered air and non-filtered air plus 25 or 50 nl 1-1 ozone) in open-top chambers during one growing season to investigate the long-term effect of this air pollutant on various growth variables.

  16. Productivity is a poor predictor of plant species richness

    Science.gov (United States)

    P.B. Adler; E.T. Borer; H. Hillebrand; Y. Hautier; A. Hector; S. Harpole; L.R. O’Halloran; J.B. Grace; M. Anderson; J.D. Bakker; L.A. Biederman; C.S. Brown; Y.M. Buckley; L.B. Calabrese; C.-J. Chu; E.E. Cleland; S.L. Collins; K.L. Cottingham; M.J. Crawley; E.I. Damschen; K.W. Davies; N.M. DeCrappeo; P.A. Fay; J. Firn; P. Frater; E.I. Gasarch; D.S. Gruner; N. Hagenah; J. Hille. Ris Lambers

    2011-01-01

    For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent...

  17. Validation of the ITS2 region as a novel DNA barcode for identifying medicinal plant species.

    Science.gov (United States)

    Chen, Shilin; Yao, Hui; Han, Jianping; Liu, Chang; Song, Jingyuan; Shi, Linchun; Zhu, Yingjie; Ma, Xinye; Gao, Ting; Pang, Xiaohui; Luo, Kun; Li, Ying; Li, Xiwen; Jia, Xiaocheng; Lin, Yulin; Leon, Christine

    2010-01-07

    The plant working group of the Consortium for the Barcode of Life recommended the two-locus combination of rbcL+matK as the plant barcode, yet the combination was shown to successfully discriminate among 907 samples from 550 species at the species level with a probability of 72%. The group admits that the two-locus barcode is far from perfect due to the low identification rate, and the search is not over. Here, we compared seven candidate DNA barcodes (psbA-trnH, matK, rbcL, rpoC1, ycf5, ITS2, and ITS) from medicinal plant species. Our ranking criteria included PCR amplification efficiency, differential intra- and inter-specific divergences, and the DNA barcoding gap. Our data suggest that the second internal transcribed spacer (ITS2) of nuclear ribosomal DNA represents the most suitable region for DNA barcoding applications. Furthermore, we tested the discrimination ability of ITS2 in more than 6600 plant samples belonging to 4800 species from 753 distinct genera and found that the rate of successful identification with the ITS2 was 92.7% at the species level. The ITS2 region can be potentially used as a standard DNA barcode to identify medicinal plants and their closely related species. We also propose that ITS2 can serve as a novel universal barcode for the identification of a broader range of plant taxa.

  18. Molecular species composition of plant cardiolipin determined by liquid chromatography mass spectrometry

    Science.gov (United States)

    Zhou, Yonghong; Peisker, Helga

    2016-01-01

    Cardiolipin (CL), an anionic phospholipid of the inner mitochondrial membrane, provides essential functions for stabilizing respiratory complexes and is involved in mitochondrial morphogenesis and programmed cell death in animals. The role of CL and its metabolism in plants are less well understood. The measurement of CL in plants, including its molecular species composition, is hampered by the fact that CL is of extremely low abundance, and that plants contain large amounts of interfering compounds including galactolipids, neutral lipids, and pigments. We used solid phase extraction by anion exchange chromatography to purify CL from crude plant lipid extracts. LC/MS was used to determine the content and molecular species composition of CL. Thus, up to 23 different molecular species of CL were detected in different plant species, including Arabidopsis, mung bean, spinach, barley, and tobacco. Similar to animals, plant CL is dominated by highly unsaturated species, mostly containing linoleic and linolenic acid. During phosphate deprivation or exposure to an extended dark period, the amount of CL decreased in Arabidopsis, accompanied with an increased degree in unsaturation. The mechanism of CL remodeling during stress, and the function of highly unsaturated CL molecular species, remains to be defined. PMID:27179363

  19. Public attitude in the city of Belgrade towards invasive alien plant species

    Directory of Open Access Journals (Sweden)

    Tomićević Jelena

    2012-01-01

    Full Text Available Biological invasions are seen as a major threat to biodiversity at a global level, while the number of new invasions is increasing at an alarming rate. Raising the awareness of the public, academic world and policy makers about the dangers caused by invasive species, is essential for the creation of the support needed to implement and coordinate the policies necessary to address this problem. The aim of this study is to determine the level of local public awareness of the existence of these plant species, examine the public attitude towards alien invasive plant species and willingness to get involved in the prevention of their spreading. The survey was conducted in four nurseries on the territory of the City of Belgrade and the investigation dealt only with alien invasive woody plant species. Thirty customers were questioned in each of the four nurseries. The results show that local public is uninformed on the issue of invasive plant species. It is necessary to constantly and intensively raise their awareness of this issue, as well as the awareness of harmful consequences that may occur due to the uncontrolled spreading of alien invasive species. This refers not only to the population that visits the nurseries and buys the plants there and to those employed in plant production and selling, but also to the whole local public and decision makers.

  20. Plant species effects on soil nutrients and chemistry in arid ecological zones.

    Science.gov (United States)

    Johnson, Brittany G; Verburg, Paul S J; Arnone, John A

    2016-09-01

    The presence of vegetation strongly influences ecosystem function by controlling the distribution and transformation of nutrients across the landscape. The magnitude of vegetation effects on soil chemistry is largely dependent on the plant species and the background soil chemical properties of the site, but has not been well quantified along vegetation transects in the Great Basin. We studied the effects of plant canopy cover on soil chemistry within five different ecological zones, subalpine, montane, pinyon-juniper, sage/Mojave transition, and desert shrub, in the Great Basin of Nevada all with similar underlying geology. Although plant species differed in their effects on soil chemistry, the desert shrubs Sarcobatus vermiculatus, Atriplex spp., Coleogyne ramosissima, and Larrea tridentata typically exerted the most influence on soil chemistry, especially amounts of K(+) and total nitrogen, beneath their canopies. However, the extent to which vegetation affected soil nutrient status in any given location was not only highly dependent on the species present, and presumably the nutrient requirements and cycling patterns of the plant species, but also on the background soil characteristics (e.g., parent material, weathering rates, leaching) where plant species occurred. The results of this study indicate that the presence or absence of a plant species, especially desert shrubs, could significantly alter soil chemistry and subsequently ecosystem biogeochemistry and function.

  1. Application of RAPD for molecular characterization of plant species of medicinal value from an arid environment.

    Science.gov (United States)

    Arif, I A; Bakir, M A; Khan, H A; Al Farhan, A H; Al Homaidan, A A; Bahkali, A H; Al Sadoon, M; Shobrak, M

    2010-11-09

    The use of highly discriminatory methods for the identification and characterization of genotypes is essential for plant protection and appropriate use. We utilized the RAPD method for the genetic fingerprinting of 11 plant species of desert origin (seven with known medicinal value). Andrachne telephioides, Zilla spinosa, Caylusea hexagyna, Achillea fragrantissima, Lycium shawii, Moricandia sinaica, Rumex vesicarius, Bassia eriophora, Zygophyllum propinquum subsp migahidii, Withania somnifera, and Sonchus oleraceus were collected from various areas of Saudi Arabia. The five primers used were able to amplify the DNA from all the plant species. The amplified products of the RAPD profiles ranged from 307 to 1772 bp. A total of 164 bands were observed for 11 plant species, using five primers. The number of well-defined and major bands for a single plant species for a single primer ranged from 1 to 10. The highest pair-wise similarities (0.32) were observed between A. fragrantissima and L. shawii, when five primers were combined. The lowest similarities (0) were observed between A. telephioides and Z. spinosa; Z. spinosa and B. eriophora; B. eriophora and Z. propinquum. In conclusion, the RAPD method successfully discriminates among all the plant species, therefore providing an easy and rapid tool for identification, conservation and sustainable use of these plants.

  2. Plant species distribution in relation to water-table depth and soil redox potential in montane riparian meadows

    Science.gov (United States)

    Kathleen A. Dwire; J. Boone Kauffman; John E. Baham

    2006-01-01

    The distribution of riparian plant species is largely driven by hydrologic and soil variables, and riparian plant communities frequently occur in relatively distinct zones along streamside elevational and soil textural gradients. In two montane meadows in northeast Oregon, USA, we examined plant species distribution in three riparian plant communities¡ªdefined as wet,...

  3. Conservation state of populations of rare plant species in highly transformed meadow steppes of Southern Opillya

    Directory of Open Access Journals (Sweden)

    I. I. Dmytrash-Vatseba

    2016-09-01

    Full Text Available Degradation of natural habitats causes rapid extinction of rare plant populations. The diversity of rare plant species in the meadow steppes of Southern Opillya (Western Ukraine depends strongly on patch area, pasture digression of vegetation and a variety of eco-coenotical conditions. The main threats for the rare components of the meadow steppe flora are reduction of habitat and overgrazing. Spatial connections between sites are unable to support a constant rare plant population. The analysis of the composition of rare plant meadow-steppe species indicated that habitats with similar rare species composition usually have similar parameters of area, stages of pasture digression and eco-coenotical conditions. Spatial connectivity of patches does not ensure species similarity of rare components of the flora. Rare plant species were grouped according to their preferences for habitat , area and condition. In small patches subject to any stage of pasture digression grow populations of Adonis vernalis L., Pulsatilla patens (L. Mill., P. grandis Wender., Stipa capillata L., S. рennata L., Chamaecytisus blockianus (Pawł. Klásková etc. On the contrary, populations of other species (Carlina onopordifolia Besser. ex Szafer., Kuecz. et Pawł., Adenophora liliifolia (L. Ledeb. ex A. DC., Crambe tataria Sebeók, Euphorbia volhynica Besser ex Racib., Stipa tirsa Stev. etc. prefer large habitats, not changed by pasture digression. Prevention of reduction of rare species diversity requires preservation (also extension of patch area and regulation of grazing intensity.

  4. Aquatic macroinvertebrate responses to native and non-native predators

    Directory of Open Access Journals (Sweden)

    Haddaway N. R.

    2014-01-01

    Full Text Available Non-native species can profoundly affect native ecosystems through trophic interactions with native species. Native prey may respond differently to non-native versus native predators since they lack prior experience. Here we investigate antipredator responses of two common freshwater macroinvertebrates, Gammarus pulex and Potamopyrgus jenkinsi, to olfactory cues from three predators; sympatric native fish (Gasterosteus aculeatus, sympatric native crayfish (Austropotamobius pallipes, and novel invasive crayfish (Pacifastacus leniusculus. G. pulex responded differently to fish and crayfish; showing enhanced locomotion in response to fish, but a preference for the dark over the light in response to the crayfish. P.jenkinsi showed increased vertical migration in response to all three predator cues relative to controls. These different responses to fish and crayfish are hypothesised to reflect the predators’ differing predation types; benthic for crayfish and pelagic for fish. However, we found no difference in response to native versus invasive crayfish, indicating that prey naiveté is unlikely to drive the impacts of invasive crayfish. The Predator Recognition Continuum Hypothesis proposes that benefits of generalisable predator recognition outweigh costs when predators are diverse. Generalised responses of prey as observed here will be adaptive in the presence of an invader, and may reduce novel predators’ potential impacts.

  5. Plant biomass and species composition along an environmental gradient in montane riparian meadows

    Science.gov (United States)

    Kathleen A. Dwire; J. Boone Kauffman; E. N. Jack Brookshire; John E. Baham

    2004-01-01

    In riparian meadows, narrow zonation of the dominant vegetation frequently occurs along the elevational gradient from the stream edge to the floodplain terrace. We measured plant species composition and above- and belowground biomass in three riparian plant communities - a priori defined as wet, moist, and dry meadow - along short streamside topographic gradients in...

  6. Biochar effects on the nursery propagation of 4 northern Rocky Mountain native plant species

    Science.gov (United States)

    Clarice P. Matt; Christopher R. Keyes; R. Kasten Dumroese

    2018-01-01

    Biochar has emerged as a promising potential amendment of soilless nursery media for plant propagation. With this greenhouse study we used biochar to displace standard soilless nursery media at 4 rates (0, 15, 30, and 45% [v:v]) and then examined media chemistry, irrigation frequency, and the growth of 4 northern Rocky Mountain native plant species: Clarkia pulchella...

  7. Plant species invasions along the latitudinal gradient in the United States

    Science.gov (United States)

    Thomas J. Stohlgren; David Barnett; Curtis Flather; John Kartesz; Bruce Peterjohn

    2005-01-01

    It has been long established that the richness of vascular plant species and many animal taxa decreases with increasing latitude, a pattern that very generally follows declines in actual and potential evapotranspiration, solar radiation, temperature, and thus, total productivity. Using county-level data on vascular plants from the United States (3000 counties in the...

  8. Public reaction to invasive plant species in a disturbed Colorado landscape

    Science.gov (United States)

    Michael T. Daab; Courtney G. Flint

    2010-01-01

    Invasive plant species degrade ecosystems in many ways. Controlling invasive plants is costly for government agencies, businesses, and individuals. North central Colorado is currently experiencing large-scale disturbance, and millions of acres are vulnerable to invasion because of natural and socioeconomic processes. Mountain pine beetles typically endemic to this...

  9. Reciprocal effects of litter from exotic and congeneric native plant species via soil nutrients

    NARCIS (Netherlands)

    Meisner, A.; De Boer, W.; Cornelissen, J.H.C.; Van der Putten, W.H.

    2012-01-01

    Invasive exotic plant species are often expected to benefit exclusively from legacy effects of their litter inputs on soil processes and nutrient availability. However, there are relatively few experimental tests determining how litter of exotic plants affects their own growth conditions compared to

  10. 75 FR 18233 - Endangered and Threatened Wildlife and Plants; 5-Year Status Reviews of 10 Southeastern Species

    Science.gov (United States)

    2010-04-09

    ...] Endangered and Threatened Wildlife and Plants; 5-Year Status Reviews of 10 Southeastern Species AGENCY: Fish.... Definitions A. Species includes any species or subspecies of fish, wildlife, or plant, and any distinct... means any species that is in danger of extinction throughout all or a significant portion of its range...

  11. 77 FR 38762 - Endangered and Threatened Wildlife and Plants; 5-Year Status Reviews of Seven Listed Species

    Science.gov (United States)

    2012-06-29

    ... reviews under the Endangered Species Act of 1973, as amended (Act), of seven animal and plant species. We... Federal Regulations (CFR) at 50 CFR 17.11 (for animals) and 17.12 (for plants). Section 4(c)(2)(A) of the... species means any species that is in danger of extinction throughout all or a significant portion of its...

  12. Plant functional traits of dominant native and invasive species in mediterranean-climate ecosystems.

    Science.gov (United States)

    Funk, Jennifer L; Standish, Rachel J; Stock, William D; Valladares, Fernando

    2016-01-01

    The idea that dominant invasive plant species outperform neighboring native species through higher rates of carbon assimilation and growth is supported by several analyses of global data sets. However, theory suggests that native and invasive species occurring in low-resource environments will be functionally similar, as environmental factors restrict the range of observed physiological and morphological trait values. We measured resource-use traits in native and invasive plant species across eight diverse vegetation communities distributed throughout the five mediterranean-climate regions, which are drought prone and increasingly threatened by human activities, including the introduction of exotic species. Traits differed strongly across the five regions. In regions with functional differences between native and invasive species groups, invasive species displayed traits consistent with high resource acquisition; however, these patterns were largely attributable to differences in life form. We found that species invading mediterranean-climate regions were more likely to be annual than perennial: three of the five regions were dominated by native woody species and invasive annuals. These results suggest that trait differences between native and invasive species are context dependent and will vary across vegetation communities. Native and invasive species within annual and perennial groups had similar patterns of carbon assimilation and resource use, which contradicts the widespread idea that invasive species optimize resource acquisition rather than resource conservation. .

  13. A retrospective analysis of pollen host plant use by stable and declining bumble bee species.

    Science.gov (United States)

    Kleijn, David; Raemakers, Ivo

    2008-07-01

    Understanding population declines has been the objective of a wide range of ecological studies. When species have become rare such studies are complicated because particular behavior or life history traits may be the cause but also the result of the decline of a species. We approached this problem by studying species' characteristics on specimens that were collected before the onset of their decline and preserved in natural history museums. In northwestern Europe, some bumble bee species declined dramatically during the 20th century whereas other, ecologically similar, species maintained stable populations. A long-standing debate focuses on whether this is caused by declining species having stricter host plant preferences. We compared the composition of pollen loads of five bumble bee species with stable populations and five with declining populations using museum specimens collected before 1950 in Belgium, England, and The Netherlands. Prior to 1950, the number of plant taxa in pollen loads of declining species was almost one-third lower than that in stable species even though individuals of stable and declining species generally originated from the same areas. There were no systematic differences in the composition of pollen loads between stable and declining species, but the plant taxa preferred by declining species before 1950 had experienced a stronger decline in the 20th century than those preferred by stable species. In 2004 and 2005, we surveyed the areas where bumble bees had been caught in the past and compared the composition of past and present pollen loads of the stable, but not of the by now locally extinct declining species. The number of collected pollen taxa was similar, but the composition differed significantly between the two periods. Differences in composition reflected the major changes in land use in northwestern Europe but also the spread of the invasive plant species Impatiens glandulifera. The main question now is why declining species

  14. The Effect of Designated Pollutants on Plant Species

    Science.gov (United States)

    1981-01-01

    L.) Burm. J. Roughlemon seedling 12 Citrus C. limo, Lisbon lemon graft 80 Citrus C. sinensis (L.) Osbeck Valencia orange graft 80 Dudleya Dudleya...CALIFORNIA UNIVERSITY OF CALIFORNIA, IR VINE IR VINE, ORANGE COUNTY, CALIFORNIA 92664 JANUARY 1981 S Approved for public release; distribution...California poppy, indigenous to the Vandenberg Air Force Base area, blooms in the spring. Since flowering of individual plants could not be closely

  15. Mycorrhizal status helps explain invasion success of alien plant species

    Czech Academy of Sciences Publication Activity Database

    Menzel, A.; Hempel, S.; Klotz, S.; Moora, M.; Pyšek, Petr; Rillig, M. C.; Zobel, M.; Kühn, I.

    2017-01-01

    Roč. 98, č. 1 (2017), s. 92-102 ISSN 0012-9658 R&D Projects: GA ČR GB14-36079G Grant - others:AV ČR(CZ) AP1002 Program:Akademická prémie - Praemium Academiae Institutional support: RVO:67985939 Keywords : plant invasion * mycorrhiza * naturalization Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 4.809, year: 2016

  16. Productivity of selected plant species adapted to arid regions. [Crassulacean metabolizing plants; Agave deserti and Ferocactus acanthodes

    Energy Technology Data Exchange (ETDEWEB)

    Nobel, P.S.

    1980-01-01

    The biomass potential of selected arid region species for alcohol production merits careful consideration. The basis for this interest is the current low agronomic use of arid lands and the potential productivity of certain species adapted to these lands. Plants displaying Crassulacean acid metabolism (CAM) are particularly interesting with reference to biomass for fuel in regions with low rainfall, because plants with this photosynthetic process are strikingly efficient in water requirements. For CAM plants, CO/sub 2/ fixation occurs primarily at night, when tissue surface temperature and hence transpirational water loss is less than daytime values. For Agave deserti in the Sonoran desert, the water-use efficiency (mass of CO/sub 2/ fixed/mass of water transpired) over an entire year is an order of magnitude or more larger than for C-3 and C-4 plants. This indicates how well adapted CAM species are to arid regions. The potential productivity per unit land area of CAM plants is fairly substantial and, therefore, of considerable economic interest for arid areas where growth of agricultural plants is minimal.

  17. Assessing the risk of Glyphosate to native plants and weedy Brassicaceae species of North Dakota

    Science.gov (United States)

    This study was conducted to determine the ecological risk to native plants and weedy Brassicaceae species which may be growing in areas affected by off target movement of glyphosate applied to glyphosate-resistant canola (Brassica napus). Ten native grass and forb species were ...

  18. Minimizing Risks of Invasive Alien Plant Species in Tropical Production Forest Management

    Directory of Open Access Journals (Sweden)

    Michael Padmanaba

    2014-08-01

    Full Text Available Timber production is the most pervasive human impact on tropical forests, but studies of logging impacts have largely focused on timber species and vertebrates. This review focuses on the risk from invasive alien plant species, which has been frequently neglected in production forest management in the tropics. Our literature search resulted in 114 publications with relevant information, including books, book chapters, reports and papers. Examples of both invasions by aliens into tropical production forests and plantation forests as sources of invasions are presented. We discuss species traits and processes affecting spread and invasion, and silvicultural practices that favor invasions. We also highlight potential impacts of invasive plant species and discuss options for managing them in production forests. We suggest that future forestry practices need to reduce the risks of plant invasions by conducting surveillance for invasive species; minimizing canopy opening during harvesting; encouraging rapid canopy closure in plantations; minimizing the width of access roads; and ensuring that vehicles and other equipment are not transporting seeds of invasive species. Potential invasive species should not be planted within dispersal range of production forests. In invasive species management, forewarned is forearmed.

  19. Effects of plant species identity, diversity and soil fertility on biodegradation of phenanthrene in soil

    NARCIS (Netherlands)

    Oyelami, A.O.; Okere, U.V.; Orwin, K.; Deyn, de G.B.; Jones, K.C.; Semple, K.T.

    2013-01-01

    The work presented in this paper investigated the effects of plant species composition, species diversity and soil fertility on biodegradation of 14C-phenanthrene in soil. The two soils used were of contrasting fertility, taken from long term unfertilised and fertilised grassland, showing

  20. Students' Perception of Plant and Animal Species: A Case Study from Rural Argentina

    Science.gov (United States)

    Nates, Juliana; Campos, Claudia; Lindemann-Matthies, Petra

    2010-01-01

    Exotic species seriously affect local biodiversity in Argentina. This article investigates how students in San Juan province perceive native and exotic species. With the help of a written questionnaire, 865 students (9-17 years old) were asked to name the plant and animal they liked most, disliked most, and perceived as most useful, and to name…

  1. Determining habitat potential and surveying for nine rare plant species in south-central Utah

    Science.gov (United States)

    Deborah J. Clark; Christine M. Groebner

    2001-01-01

    In south-central Utah, lands within and adjacent to Capitol Reef National Park contain populations of nine rare plant species. In an effort to enhance the combined knowledge about these species, the Bureau of Land Management, the USDA Forest Service, and the National Park Service signed an Interagency Agreement and hired an interagency biologist and field crew to...

  2. Danger to biodiversity of High Tatras by spreading of invasive plant species

    International Nuclear Information System (INIS)

    Strba, P.; Gogolakova, A.

    2010-01-01

    The aim of our work was to analyze the current status of invasive plant species - their generic representation and current extension (horizontal and vertical extension). The authors used the method of inventory of species richness. Sites were recorded on a tourist map and GPS (Garmin).

  3. Soil microbial species loss affects plant biomass and survival of an introduced bacterial strain, but not inducible plant defences.

    Science.gov (United States)

    Kurm, Viola; van der Putten, Wim H; Pineda, Ana; Hol, W H Gera

    2018-02-12

    Plant growth-promoting rhizobacteria (PGPR) strains can influence plant-insect interactions. However, little is known about the effect of changes in the soil bacterial community in general and especially the loss of rare soil microbes on these interactions. Here, the influence of rare soil microbe reduction on induced systemic resistance (ISR) in a wild ecotype of Arabidopsis thaliana against the aphid Myzus persicae was investigated. To create a gradient of microbial abundances, soil was inoculated with a serial dilution of a microbial community and responses of Arabidopsis plants that originated from the same site as the soil microbes were tested. Plant biomass, transcription of genes involved in plant defences, and insect performance were measured. In addition, the effects of the PGPR strain Pseudomonas fluorescens SS101 on plant and insect performance were tested under the influence of the various soil dilution treatments. Plant biomass showed a hump-shaped relationship with soil microbial community dilution, independent of aphid or Pseudomonas treatments. Both aphid infestation and inoculation with Pseudomonas reduced plant biomass, and led to downregulation of PR1 (salicylic acid-responsive gene) and CYP79B3 (involved in synthesis of glucosinolates). Aphid performance and gene transcription were unaffected by soil dilution. Neither the loss of rare microbial species, as caused by soil dilution, nor Pseudomonas affect the resistance of A. thaliana against M. persicae. However, both Pseudomonas survival and plant biomass respond to rare species loss. Thus, loss of rare soil microbial species can have a significant impact on both above- and below-ground organisms. © The Author(s) 2018. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Biotic interactions overrule plant responses to climate, depending on the species' biogeography.

    Directory of Open Access Journals (Sweden)

    Astrid Welk

    Full Text Available This study presents an experimental approach to assess the relative importance of climatic and biotic factors as determinants of species' geographical distributions. We asked to what extent responses of grassland plant species to biotic interactions vary with climate, and to what degree this variation depends on the species' biogeography. Using a gradient from oceanic to continental climate represented by nine common garden transplant sites in Germany, we experimentally tested whether congeneric grassland species of different geographic distribution (oceanic vs. continental plant range type responded differently to combinations of climate, competition and mollusc herbivory. We found the relative importance of biotic interactions and climate to vary between the different components of plant performance. While survival and plant height increased with precipitation, temperature had no effect on plant performance. Additionally, species with continental plant range type increased their growth in more benign climatic conditions, while those with oceanic range type were largely unable to take a similar advantage of better climatic conditions. Competition generally caused strong reductions of aboveground biomass and growth. In contrast, herbivory had minor effects on survival and growth. Against expectation, these negative effects of competition and herbivory were not mitigated under more stressful continental climate conditions. In conclusion we suggest variation in relative importance of climate and biotic interactions on broader scales, mediated via species-specific sensitivities and factor-specific response patterns. Our results have important implications for species distribution models, as they emphasize the large-scale impact of biotic interactions on plant distribution patterns and the necessity to take plant range types into account.

  5. Attraction of Phytoseiulus persimilis (Acari: Phytoseiidae) towards volatiles from various Tetranychus urticae-infested plant species.

    Science.gov (United States)

    van den Boom, C E M; van Beek, T A; Dicke, M

    2002-12-01

    Plants infested with the spider mite Tetranychus urticae Koch, may indirectly defend themselves by releasing volatiles that attract the predatory mite Phytoseiulus persimilis Athias-Henriot. Several plants from different plant families that varied in the level of spider mite acceptance were tested in an olfactometer. The predatory mites were significantly attracted to the spider mite-infested leaves of all test plant species. No differences in attractiveness of the infested plant leaves were found for predatory mites reared on spider mites on the different test plants or on lima bean. Thus, experience with the spider mite-induced plant volatiles did not affect the predatory mites. Jasmonic acid was applied to ginkgo leaves to induce a mimic of a spider mite-induced volatile blend, because the spider mites did not survive when incubated on ginkgo. The volatile blend induced in ginkgo by jasmonic acid was slightly attractive to predatory mites. Plants with a high degree of direct defence were thought to invest less in indirect defence than plants with a low degree of direct defence. However, plants that had a strong direct defence such as ginkgo and sweet pepper, did emit induced volatiles that attracted the predatory mite. This indicates that a combination of direct and indirect defence is to some extent compatible in plant species.

  6. Profiling mRNAs of two Cuscuta species reveals possible candidate transcripts shared by parasitic plants.

    Directory of Open Access Journals (Sweden)

    Linjian Jiang

    Full Text Available Dodders are among the most important parasitic plants that cause serious yield losses in crop plants. In this report, we sought to unveil the genetic basis of dodder parasitism by profiling the trancriptomes of Cuscuta pentagona and C. suaveolens, two of the most common dodder species using a next-generation RNA sequencing platform. De novo assembly of the sequence reads resulted in more than 46,000 isotigs and contigs (collectively referred to as expressed sequence tags or ESTs for each species, with more than half of them predicted to encode proteins that share significant sequence similarities with known proteins of non-parasitic plants. Comparing our datasets with transcriptomes of 12 other fully sequenced plant species confirmed a close evolutionary relationship between dodder and tomato. Using a rigorous set of filtering parameters, we were able to identify seven pairs of ESTs that appear to be shared exclusively by parasitic plants, thus providing targets for tailored management approaches. In addition, we also discovered ESTs with sequences similarities to known plant viruses, including cryptic viruses, in the dodder sequence assemblies. Together this study represents the first comprehensive transcriptome profiling of parasitic plants in the Cuscuta genus, and is expected to contribute to our understanding of the molecular mechanisms of parasitic plant-host plant interactions.

  7. Profiling mRNAs of two Cuscuta species reveals possible candidate transcripts shared by parasitic plants.

    Science.gov (United States)

    Jiang, Linjian; Wijeratne, Asela J; Wijeratne, Saranga; Fraga, Martina; Meulia, Tea; Doohan, Doug; Li, Zhaohu; Qu, Feng

    2013-01-01

    Dodders are among the most important parasitic plants that cause serious yield losses in crop plants. In this report, we sought to unveil the genetic basis of dodder parasitism by profiling the trancriptomes of Cuscuta pentagona and C. suaveolens, two of the most common dodder species using a next-generation RNA sequencing platform. De novo assembly of the sequence reads resulted in more than 46,000 isotigs and contigs (collectively referred to as expressed sequence tags or ESTs) for each species, with more than half of them predicted to encode proteins that share significant sequence similarities with known proteins of non-parasitic plants. Comparing our datasets with transcriptomes of 12 other fully sequenced plant species confirmed a close evolutionary relationship between dodder and tomato. Using a rigorous set of filtering parameters, we were able to identify seven pairs of ESTs that appear to be shared exclusively by parasitic plants, thus providing targets for tailored management approaches. In addition, we also discovered ESTs with sequences similarities to known plant viruses, including cryptic viruses, in the dodder sequence assemblies. Together this study represents the first comprehensive transcriptome profiling of parasitic plants in the Cuscuta genus, and is expected to contribute to our understanding of the molecular mechanisms of parasitic plant-host plant interactions.

  8. Assessment of potential indigenous plant species for the phytoremediation of arsenic-contaminated areas of Bangladesh.

    Science.gov (United States)

    Mahmud, Rezwanul; Inoue, Naoto; Kasajima, Shin-Ya; Shaheen, Riffat

    2008-01-01

    Soil and water contaminated with arsenic (As) pose a major environmental and human health problem in Bangladesh. Phytoremediation, a plant-based technology, may provide an economically viable solution for remediating the As-polluted sites. The use of indigenous plants with a high tolerance and accumulation capacity for As may be a very convenient approach for phytoremediation. To assess the potential of native plant species for phytoremediation, plant and soil samples were collected from four As-contaminated (groundwater) districts in Bangladesh. The main criteria used for selecting plants for phytoremediation were high bioconcentration factors (BCFs) and translocation factors (TFs) of As. From the results of a screening of 49 plant species belonging to 29 families, only one species of fern (Dryopteris filix-mas), three herbs (Blumea lacera, Mikania cordata, and Ageratum conyzoides), and two shrubs (Clerodendrum trichotomum and Ricinus communis) were found to be suitable for phytoremediation. Arsenic bioconcentration and translocation factors > 1 suggest that these plants are As-tolerant accumulators with potential use in phytoextraction. Three floating plants (Eichhornia crassipes, Spirodela polyrhiza, and Azolla pinnata) and a common wetland weed (Monochoria vaginalis) also showed high BCF and TF values; therefore, these plants may be promising candidates for cleaningup As-contaminated surface water and wetland areas. The BCF of Oryza sativa, obtained from As-contaminated districts was > 1, which highlights possible food-chain transfer issues for As-contaminated areas in Bangladesh.

  9. Rarity, Species Richness, and the Threat of Extinction—Are Plants the Same as Animals?

    OpenAIRE

    Knapp, Sandra

    2011-01-01

    Assessment of conservation status is done both for areas or habitats and for species (or taxa). IUCN Red List categories have been the principal method of categorising species in terms of extinction risk, and have been shown to be robust and helpful in the groups for which they have been developed. A recent study highlights properties associated with extinction risk in flowering plants, focusing on the species-rich hot spot of the Cape region of South Africa, and concludes that merely followi...

  10. Richness of Ancient Forest Plant Species Indicates Suitable Habitats for Macrofungi

    Czech Academy of Sciences Publication Activity Database

    Hofmeister, J.; Hošek, J.; Brabec, Marek; Dvořák, D.; Beran, M.; Deckerová, H.; Burel, J.; Kříž, M.; Borovička, Jan; Běťák, J.; Vašutová, Martina

    2014-01-01

    Roč. 23, č. 8 (2014), s. 2015-2031 ISSN 0960-3115 Grant - others:GA MŽP(CZ) SP/2D1/146/08 Institutional support: RVO:67985807 ; RVO:67985831 ; RVO:67179843 Keywords : diversity * forest continuity * forest management * Herb-layer plant species * red-listed species * species richness * surrogacy Subject RIV: BB - Applied Statistics, Operational Research; EH - Ecology, Behaviour (GLU-S); EH - Ecology, Behaviour (UEK-B) Impact factor: 2.365, year: 2014

  11. Predicting the presence and cover of management relevant invasive plant species on protected areas.

    Science.gov (United States)

    Iacona, Gwenllian; Price, Franklin D; Armsworth, Paul R

    2016-01-15

    Invasive species are a management concern on protected areas worldwide. Conservation managers need to predict infestations of invasive plants they aim to treat if they want to plan for long term management. Many studies predict the presence of invasive species, but predictions of cover are more relevant for management. Here we examined how predictors of invasive plant presence and cover differ across species that vary in their management priority. To do so, we used data on management effort and cover of invasive plant species on central Florida protected areas. Using a zero-inflated multiple regression framework, we showed that protected area features can predict the presence and cover of the focal species but the same features rarely explain both. There were several predictors of either presence or cover that were important across multiple species. Protected areas with three days of frost per year or fewer were more likely to have occurrences of four of the six focal species. When invasive plants were present, their proportional cover was greater on small preserves for all species, and varied with surrounding household density for three species. None of the predictive features were clearly related to whether species were prioritized for management or not. Our results suggest that predictors of cover and presence can differ both within and across species but do not covary with management priority. We conclude that conservation managers need to select predictors of invasion with care as species identity can determine the relationship between predictors of presence and the more management relevant predictors of cover. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Chemical Composition and Seasonality of Aromatic Mediterranean Plant Species by NMR-Based Metabolomics

    Directory of Open Access Journals (Sweden)

    Monica Scognamiglio

    2015-01-01

    Full Text Available An NMR-based metabolomic approach has been applied to analyse seven aromatic Mediterranean plant species used in traditional cuisine. Based on the ethnobotanical use of these plants, the approach has been employed in order to study the metabolic changes during different seasons. Primary and secondary metabolites have been detected and quantified. Flavonoids (apigenin, quercetin, and kaempferol derivatives and phenylpropanoid derivatives (e.g., chlorogenic and rosmarinic acid are the main identified polyphenols. The richness in these metabolites could explain the biological properties ascribed to these plant species.

  13. Chemical Composition and Seasonality of Aromatic Mediterranean Plant Species by NMR-Based Metabolomics.

    Science.gov (United States)

    Scognamiglio, Monica; D'Abrosca, Brigida; Esposito, Assunta; Fiorentino, Antonio

    2015-01-01

    An NMR-based metabolomic approach has been applied to analyse seven aromatic Mediterranean plant species used in traditional cuisine. Based on the ethnobotanical use of these plants, the approach has been employed in order to study the metabolic changes during different seasons. Primary and secondary metabolites have been detected and quantified. Flavonoids (apigenin, quercetin, and kaempferol derivatives) and phenylpropanoid derivatives (e.g., chlorogenic and rosmarinic acid) are the main identified polyphenols. The richness in these metabolites could explain the biological properties ascribed to these plant species.

  14. Phytoaccumulation of trace elements by wetland plants: 3. Uptake and accumulation of ten trace elements by twelve plant species

    Energy Technology Data Exchange (ETDEWEB)

    Qian, J.H.; Zayed, A.; Zhu, Y.L.; Yu, M.; Terry, N.

    1999-10-01

    Interest is increasing in using wetland plants in constructed wetlands to remove toxic elements from polluted wastewater. To identify those wetland plants that hyperaccumulate trace elements, 12 plant species were tested for their efficiency to bioconcentrate 10 potentially toxic trace elements including As, b, Cd, Cr, Cu, Pb, Mn, Hg, Ni, and Se. Individual plants were grown under carefully controlled conditions and supplied with 1 mg L{sup {minus}1} of each trace element individually for 10 d. Except B, all elements accumulated to much higher concentrations in roots than in shoots. Highest shoot tissue concentrations (mg kg{sup {minus}1} DW) of the various trace elements were attained by the following species: umbrella plant (Cyperus alternifolius L.) for Mn (198) and Cr (44); water zinnia (Wedelia trilobata Hitchc.) for Cd (148) and Ni (80); smartweed (Polygonum hydropiperoides Michx.) for Cu (95) and Pb (64); water lettuce (Pistia stratiotes L.) for Hg (92), As (34), and Se (39); and mare's tail (hippuris vulgaris L.) for B (1132). Whereas, the following species attained the highest root tissue concentrations (mg kg{sup {minus}1} DW); stripped rush (Baumia rubiginosa) for Mn (1683); parrot's feather (Myriophyllum brasiliense Camb.) for Cd (1426) and Ni (1077); water lettuce for Cu (1038), Hg (1217), and As (177); smartweed for Cr (2980) and Pb (1882); mare's tail for B (1277); and monkey flower (Mimulus guttatus Fisch.) for Se (384). From a phytoremediation perspective, smartweed was probably the best plant species for trace element removal from wastewater due to its faster growth and higher plant density.

  15. Iron Requirement and Iron Uptake from Various Iron Compounds by Different Plant Species

    Science.gov (United States)

    Christ, Rudolf A.

    1974-01-01

    The Fe requirements of four monocotyledonous plant species (Avena sativa L., Triticum aestivum L., Oryza sativa L., Zea mays L.) and of three dicotyledonous species (Lycopersicum esculentum Mill., Cucumis sativus L., Glycine maxima (L.) Merr.) in hydroponic cultures were ascertained. Fe was given as NaFe-EDDHA chelate (Fe ethylenediamine di (O-hydroxyphenylacetate). I found that the monocotyledonous species required a substantially higher Fe concentration in the nutrient solution in order to attain optimum growth than did the dicotyledonous species. Analyses showed that the process of iron uptake was less efficient with the monocotyledonous species. When the results obtained by using chelated Fe were compared with those using ionic Fe, it was shown that the inefficient species were equally inefficient in utilizing Fe3+ ions. However, the differences between the efficient and the inefficient species disappeared when Fe2+ was used. This confirms the work of others who postulated that Fe3+ is reduced before uptake of chelated iron by the root. In addition, it was shown that reduction also takes place when Fe is used in ionic form. The efficiency of Fe uptake seems to depend on the efficiency of the root system of the particular plant species in reducing Fe3+. The removal of Fe from the chelate complex after reduction to Fe2+ seems to present no difficulties to the various plant species. PMID:16658933

  16. Intra-specific downsizing of frugivores affects seed germination of fleshy-fruited plant species

    Science.gov (United States)

    Pérez-Méndez, Néstor; Rodríguez, Airam; Nogales, Manuel

    2018-01-01

    The loss of largest-bodied individuals within species of frugivorous animals is one of the major consequences of defaunation. The gradual disappearance of large-bodied frugivores is expected to entail a parallel deterioration in seed dispersal functionality if the remaining smaller-sized individuals are not so effective as seed dispersers. While the multiple impacts of the extinction of large bodied species have been relatively well studied, the impact of intraspecific downsizing (i.e. the extinction of large individuals within species) on seed dispersal has rarely been evaluated. Here we experimentally assessed the impact of body-size reduction in the frugivorous lizard Gallotia galloti (Lacertidae), an endemic species of the Canary Islands, on the seed germination patterns of two fleshy-fruited plant species (Rubia fruticosa and Withania aristata). Seed germination curves and the proportions of germinated seeds were compared for both plant species after being defecated by large-sized individuals and small-sized individuals. The data show that seeds of W. aristata defecated by larger-sized lizards germinated faster and in a higher percentage than those defecated by small-sized lizards, while no differences were found for R. fruticosa seeds. Our results suggest that disappearance of the largest individuals of frugivorous species may impair recruitment of some plant species by worsening seed germination. They also warn us of a potential cryptic loss of seed dispersal functionality on defaunated ecosystems, even when frugivorous species remain abundant.

  17. Effect of diesel fuel on growth of selected plant species

    OpenAIRE

    Adam, G.; Duncan, H.J.

    1999-01-01

    Diesel oil is a complex mixture of hydrocarbons with an average carbon number of C8–\\ud C26. The majority of components consist of alkanes, both straight chained and branched and aromatic\\ud compounds including mono-, di- and polyaromatic hydrocarbons. Regardless of this complexity,\\ud diesel oil can be readily degraded by a number of soil microorganisms making it a likely candidate for\\ud bioremediation. The concept of using plants to enhance bioremediation, termed phytoremediation,\\ud is a ...

  18. Long-term trends of native and non-native fish faunas in the American Southwest

    Directory of Open Access Journals (Sweden)

    Olden, J. D.

    2005-06-01

    Full Text Available Environmental degradation and the proliferation of non-native fish species threaten the endemic, and highly unique fish faunas of the American Southwest. The present study examines long-term trends (> 160 years of fish species distributions in the Lower Colorado River Basin and identifies those native species (n = 28 exhibiting the greatest rates of decline and those non-native species (n = 48 exhibiting the highest rates of spread. Among the fastest expanding invaders in the basin are red shiner (Cyprinella lutrensis, fathead minnow (Pimephales promelas, green sunfish (Lepomis cyanellus, largemouth bass (Micropterus salmoides, western mosquitofish (Gambussia affinis and channel catfish (Ictalurus punctatus; species considered to be the most invasive in terms of their negative impacts on native fish communities. Interestingly, non-native species that have been recently introduced (1950+ have generally spread at substantially lower rates as compared to species introduced prior to this time (especially from 1920 to 1950, likely reflecting reductions in human-aided spread of species. We found general agreement between patterns of species decline and extant distribution sizes and official listing status under the U.S. Endangered Species Act. ‘Endangered’ species have generally experienced greater declines and have smaller present-day distributions compared to ‘threatened’ species, which in turn have shown greater declines and smaller distributions than those species not currently listed. A number of notable exceptions did exist, however, and these may provide critical information to help guide the future listing of species (i.e., identification of candidates and the upgrading or downgrading of current listed species that are endemic to the Lower Colorado River Basin. The strong correlation between probability estimates of local extirpation and patterns of native species decline and present-day distributions suggest a possible proactive

  19. Hierarchical Learning of Tree Classifiers for Large-Scale Plant Species Identification.

    Science.gov (United States)

    Fan, Jianping; Zhou, Ning; Peng, Jinye; Gao, Ling

    2015-11-01

    In this paper, a hierarchical multi-task structural learning algorithm is developed to support large-scale plant species identification, where a visual tree is constructed for organizing large numbers of plant species in a coarse-to-fine fashion and determining the inter-related learning tasks automatically. For a given parent node on the visual tree, it contains a set of sibling coarse-grained categories of plant species or sibling fine-grained plant species, and a multi-task structural learning algorithm is developed to train their inter-related classifiers jointly for enhancing their discrimination power. The inter-level relationship constraint, e.g., a plant image must first be assigned to a parent node (high-level non-leaf node) correctly if it can further be assigned to the most relevant child node (low-level non-leaf node or leaf node) on the visual tree, is formally defined and leveraged to learn more discriminative tree classifiers over the visual tree. Our experimental results have demonstrated the effectiveness of our hierarchical multi-task structural learning algorithm on training more discriminative tree classifiers for large-scale plant species identification.

  20. A simple and efficient method for isolating small RNAs from different plant species

    Directory of Open Access Journals (Sweden)

    de Folter Stefan

    2011-02-01

    Full Text Available Abstract Background Small RNAs emerged over the last decade as key regulators in diverse biological processes in eukaryotic organisms. To identify and study small RNAs, good and efficient protocols are necessary to isolate them, which sometimes may be challenging due to the composition of specific tissues of certain plant species. Here we describe a simple and efficient method to isolate small RNAs from different plant species. Results We developed a simple and efficient method to isolate small RNAs from different plant species by first comparing different total RNA extraction protocols, followed by streamlining the best one, finally resulting in a small RNA extraction method that has no need of first total RNA extraction and is not based on the commercially available TRIzol® Reagent or columns. This small RNA extraction method not only works well for plant tissues with high polysaccharide content, like cactus, agave, banana, and tomato, but also for plant species like Arabidopsis or tobacco. Furthermore, the obtained small RNA samples were successfully used in northern blot assays. Conclusion Here we provide a simple and efficient method to isolate small RNAs from different plant species, such as cactus, agave, banana, tomato, Arabidopsis, and tobacco, and the small RNAs from this simplified and low cost method is suitable for downstream handling like northern blot assays.