scholarly journals Reducing nutrient availability and enhancing biotic resistance limits settlement and growth of the invasive Australian swamp stonecrop (Crassula helmsii)

2020 ◽  
Vol 22 (11) ◽  
pp. 3391-3402
Author(s):  
Janneke M. M. van der Loop ◽  
Janne Tjampens ◽  
Joost J. Vogels ◽  
Hein H. van Kleef ◽  
Leon P. M. Lamers ◽  
...  
Keyword(s):  
Nutrient Availability ◽  
Native Species ◽  
Western Europe ◽  
Biotic Resistance ◽  
Habitat Type ◽  
Freshwater Ecosystems ◽  
Freshwater Wetlands ◽  
Native Plant ◽  
Alien Plant ◽  
Bare Soils

Abstract The invasive Australian swamp stonecrop, Crassula helmsii, is a perennial amphibious herb originating from Australia and New Zealand. In freshwater wetlands of North-western Europe, this alien plant species is invasive due to its efficient colonization of empty niches. The establishment of dense C. helmsii growth is threatening native biodiversity and functioning of freshwater ecosystems, especially oligotrophic wetlands with high disturbance and nutrient enrichments. As the effects of these potential drivers of ecosystem degradation are generally difficult to determine in the field, we tested the competitive strength of C. helmsii in a greenhouse experiment with two native competitor species of the same habitat type, Pilularia globulifera and Littorella uniflora. Sods dominated by either of the native species, as well as bare soils, were collected from the field and manually infested with propagules of C. helmsii. Settlement and growth of C. helmsii was assessed after five weeks. In addition, the effect of nutrient enrichment by water bird feces on competition was studied by adding waterfowl droppings. C. helmsii was able to settle successfully in all treatments, but P. globulifera and L. uniflora dominance reduced settlement success and growth of C. helmsii. On vegetated sods, the addition of waterfowl droppings had a low effect on the performance of C. helmsii, however, this treatment significantly increased biomass production on bare soils with low nutrient availability. We conclude that both absence of native competitors and eutrophication, including guanotrophication by waterfowl, explain the establishment success and invasiveness of C. helmsii. Given the fact that eradication of C. helmsii is very challenging, our results imply that management should focus on a combination of increasing local species densities and abating eutrophication. This will strongly limit the window of opportunity for invasion of C. helmsii and enhance resistance by native plant communities.

scholarly journals Non-native species in the vascular flora of highlands and mountains of Iceland

2015 ◽  
Author(s):  
Pawel Wasowicz
Keyword(s):  
Plant Species ◽  
Native Species ◽  
Hot Springs ◽  
Vascular Plant ◽  
Temporal Trends ◽  
Plant Colonization ◽  
Native Plant ◽  
Alien Plant ◽  
Alien Flora ◽  
Central Highland

Highlands and mountains of Iceland (defined here as areas located above 400 m a.s.l) are considered to be the largest remaining wilderness areas in Europe. The present study provides first comprehensive and up-to-date data on non-native plant species from this area. The study was aimed to provide a checklist of alien plant species recorded from highland and mountain areas of Iceland, assess their naturalisation status, define spatial patterns and hotspots of their distribution and analyse temporal trends in the data. The presence of 18 non-native vascular plant species was evidenced including 13 casuals and 5 naturalised taxa (1 invasive). The results showed that the central highland is most vulnerable to alien plant colonisation, while mountain and highland areas in other parts of the country are much less impacted by non-native plant taxa. Clear hotspots of occurrence of alien flora can be defined and their geographic location corresponds to places of touristic interest such as hot springs, geothermal areas, mountain huts and shelters as well as main roads and tracks. Temporal trends characterizing non-native plant colonization show clearly that the process is still in its initial phase. The research suggests that human-mediated dispersal is the major force contributing to increased invasion risk within the investigated area.

scholarly journals Diversity and biomass of native macrophytes are negatively related to dominance of an invasive Poaceae in Brazilian sub-tropical streams

2013 ◽  
Vol 25 (2) ◽  
pp. 202-209 ◽  
Author(s):  
Luiz Felipe Gonçalves Fernandes ◽  
Mariana Carolina Teixeira ◽  
Sidinei Magela Thomaz
Keyword(s):  
Native Species ◽  
Biotic Resistance ◽  
Aquatic Macrophyte ◽  
Shannon Index ◽  
Freshwater Ecosystems ◽  
Freshwater Biodiversity ◽  
Native Communities ◽  
Environmental Perturbations ◽  
Mechanical Removal ◽  
Successful Invader

Besides exacerbated exploitation, pollution, flow alteration and habitats degradation, freshwater biodiversity is also threatened by biological invasions. This paper addresses how native aquatic macrophyte communities are affected by the non-native species Urochloa arrecta, a current successful invader in Brazilian freshwater systems. We compared the native macrophytes colonizing patches dominated and non-dominated by this invader species. We surveyed eight streams in Northwest Paraná State (Brazil). In each stream, we recorded native macrophytes' richness and biomass in sites where U. arrecta was dominant and in sites where it was not dominant or absent. No native species were found in seven, out of the eight investigated sites where U. arrecta was dominant. Thus, we found higher native species richness, Shannon index and native biomass values in sites without dominance of U. arrecta than in sites dominated by this invader. Although difficult to conclude about causes of such differences, we infer that the elevated biomass production by this grass might be the primary reason for alterations in invaded environments and for the consequent impacts on macrophytes' native communities. However, biotic resistance offered by native richer sites could be an alternative explanation for our results. To mitigate potential impacts and to prevent future environmental perturbations, we propose mechanical removal of the invasive species and maintenance or restoration of riparian vegetation, for freshwater ecosystems have vital importance for the maintenance of ecological services and biodiversity and should be preserved.

scholarly journals Nitrate reductase activity (NRA) in the invasive alien Fallopia japonica: seasonal variation, differences among habitats types, and comparison with native species

2016 ◽  
Vol 85 (3) ◽  
Author(s):  
Damian Chmura ◽  
Marek Krywult ◽  
Janusz Leszek Kozak
Keyword(s):  
Nitrate Reductase ◽  
Native Species ◽  
Nitrate Reductase Activity ◽  
Plant Traits ◽  
Reductase Activity ◽  
Invasion Success ◽  
Native Plant ◽  
Japanese Knotweed ◽  
Alien Plant ◽  
Invasive Alien Plant

Nitrate reductase activity (NRA) was studied in the invasive alien plant <em>F. japonica</em> (Japanese knotweed) during the vegetation season and among natural, semi-natural, and human-made habitats and compared with NRA in selected native species. NRA was measured directly in the field from the beginning of May until the beginning of October. NRA was much higher than in the plant’s native range, i.e., East Asia, and showed a high degree of variation over time with the highest values being reached at the stage of fast vegetative growth and at the beginning of fruiting. NRA was highest on dumping sites probably due to the high nitrogen input into soils and near traffic and the emission of NO<span><em><sub>x</sub></em></span> by vehicles. A comparison of the enzyme activity in four selected native plant species indicated that NRA in <em>F. japonica</em> was the highest with the exception of <em>Urtica dioica</em>, which exhibited a similar activity of the enzyme. A detailed comparison with this species showed that differences between these species on particular dates were influenced by differences in the phenology of both plants. The initial results that were obtained suggest that nitrogen pollution in an environment can contribute to habitat invasibility and a high level of NRA, which in addition to the many plant traits that are commonly accepted as characteristic of invasiveness features, may be an important factor that enhances invasion success.

scholarly journals Non-native species in the vascular flora of highlands and mountains of Iceland

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1559 ◽  
Author(s):  
Pawel Wasowicz
Keyword(s):  
Alien Species ◽  
Plant Species ◽  
Hot Spots ◽  
Native Species ◽  
Vascular Plant ◽  
Temporal Trends ◽  
Plant Colonization ◽  
Native Plant ◽  
Alien Plant ◽  
Vascular Plant Species

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.

scholarly journals Effects of cutting and sowing seeds of native species on giant ragweed invasion and plant diversity in a field experiment

2020 ◽  
Vol 44 (1) ◽  
Author(s):  
Chaeho Byun ◽  
Ho Choi ◽  
Hojeong Kang
Keyword(s):  
Field Experiment ◽  
Plant Diversity ◽  
Native Species ◽  
Native Plants ◽  
Biotic Resistance ◽  
Plant Cover ◽  
Effective Control ◽  
Native Plant ◽  
Effective Measure ◽  
Ambrosia Trifida

Abstract Background Ambrosia trifida is a highly invasive annual plant, but effective control methods have not been proposed. Among various eradication methods, cutting is a simple measure to control invasive plants, and sowing seeds of native plants may effectively increase biotic resistance to invasion. In this study, we conducted a field experiment with two treatments: cutting and sowing seeds of six native or naturalized plants. Results We found a significantly lower A. trifida abundance after cutting than in the control (77% decrease). Sowing seeds of native species did not provide any additional benefit for the control of A. trifida, but increased the importance values and diversity of other native vegetation. The abundance of A. trifida was negatively correlated with that of other plant taxa based on plant cover, biomass, and density. However, biotic resistance of sown plants was not effective to control invasion because A. trifida was so competitive. Conclusions We concluded that cutting is an effective measure to control Ambrosia trifida while sowing seeds of native plants can increase native plant diversity.

Plant invasions: the role of biotic interactions - an overview.

2020 ◽  
pp. 1-25
Author(s):  
Anna Traveset ◽  
David M. Richardson
Keyword(s):  
Plant Invasion ◽  
Native Species ◽  
Biotic Resistance ◽  
Biotic Interactions ◽  
Invasion Biology ◽  
Plant Invasions ◽  
Ecological Communities ◽  
Native Plant ◽  
Common Garden Experiments

Abstract Diverse biotic interactions between non-native plant species and other species from all taxonomic groups are crucial mediators of the dynamics of plant invasions. This chapter reviews the key hypotheses in invasion ecology that invoke biotic interactions to explain aspects of plant invasion dynamics. We examine the historical context of these hypotheses and assess the evidence for accepting or rejecting their predictions. Most hypotheses invoke antagonistic interactions, mainly competition, predation, herbivory interactions and the role of pathogens. Only in the last two decades have positive (facilitative/mutualistic) interactions been explicitly included in invasion biology theory (as in ecological theory in general). Much information has accumulated in testing hypotheses relating to biotic resistance and Enemy Release Theory, although many of the emerging generalizations are still contentious. There is growing consensus that other drivers of plant invasion success, such as propagule pressure and disturbance, mediate the outcome of biotic interactions, thereby complicating our ability to make predictions, but these have rarely been assessed in both native and adventive ranges of non-native invasive species. It is also widely acknowledged that biogeographic comparisons, more than common garden experiments, are needed to shed light on many of the contradictory results. Contrasting findings have also emerged in exploring the roles of positive interactions. Despite strong evidence that such interactions are crucial in many communities, more work is needed to elucidate the factors that influence the relative importance of positive and negative interactions in different ecosystems. Different types of evidence in support of invasional meltdown have emerged for diverse habitats and across spatial scales. In light of increasing evidence that biotic indirect effects are crucial determinants of the structure, dynamics and evolution of ecological communities, both direct and indirect interactions involving native and non-native species must be considered to determine how they shape plant invasion patterns and the ecological impacts of non-native species on recipient communities. Research that examines both biotic interactions and the factors that mediate their strength and alter interaction outcomes is needed to improve our ability to predict the effects of novel interactions between native and non-native species, and to envisage how existing invaded communities will respond to changing environmental conditions. Many opportunities exist for manipulating biotic interactions as part of integrated control strategies to reduce the extent, density and impacts of non-native plant invasions. These include the introduction of species from the native range of the non-native plant for biological control, diverse manipulations of plant - herbivore interactions and many types of interaction to enhance biotic resistance and steer vegetation recovery following non-native plant control.

scholarly journals Distribution and Habitat Preferences of the Invasive Alien Rosa rugosa (Rosaceae) in Archipelago Sea National Park, SW Finland

2017 ◽  
Vol 62 (1) ◽  
pp. 99-115
Author(s):  
Panu Kunttu ◽  
Sanna-Mari Kunttu
Keyword(s):  
National Park ◽  
Habitat Preferences ◽  
Habitat Type ◽  
Sandy Beaches ◽  
Native Plant ◽  
Rosa Rugosa ◽  
Alien Plant ◽  
Invasive Alien Plant ◽  
Archipelago Sea ◽  
Control Work

AbstractRosa rugosa Thunb. is an invasive alien plant which was introduced from East Asia to Europe in the 19th century. Over the decades it has spread along the Finnish coast, including the archipelagos of the Baltic Sea. The shrub grows particularly along sandy beaches, stony shores and seashore meadows. There it leads to serious changes in coastal ecosystems and replaces native plant species. This paper presents the distribution and habitat preferences of R. rugosa in and near Archipelago Sea National Park in SW Finland. We identified 205 stands in the study area, 58% of them in protected areas. Systematic inventories do not cover the whole study area, so it is likely that dozens of stands remain undiscovered. Stands of the species were concentrated on the outer islands, where the archipelago’s most characteristic flora and fauna occur. Data on the shore type and area of all stands were collected. The total area covered by R. rugosa was 7277 m2 before control work started in 2008. The largest stand occurred on Örö Island, covering ca 2500 m2 before its eradication, and the median size of all stands was 6 m2. Five of the six largest stands were on sandy beach, but stony shore was the most common habitat type.

scholarly journals Increase in nutrient availability promotes success of invasive plants through increasing growth and decreasing anti-herbivory defenses

2021 ◽  
Author(s):  
Liping Shan ◽  
Ayub M.O. Oduor ◽  
Wei Huang ◽  
Yanjie Liu
Keyword(s):  
Invasive Species ◽  
Plant Species ◽  
Invasive Plants ◽  
Nutrient Availability ◽  
Nutrient Enrichment ◽  
Native Species ◽  
Native Plants ◽  
Native Plant ◽  
Simulated Herbivory ◽  
Native Plant Species

Invasive plant species often exhibit greater growth and lower anti-herbivory defense than native plant species. However, it remains unclear how nutrient enrichment of invaded habitats may interact with competition from resident native plants to affect growth and defense of invasive plants. In a greenhouse experiment, we grew five congeneric pairs of invasive and native plant species under two levels of nutrient availability (low vs. high) that were fully crossed with simulated herbivory (clipping vs. no-clipping) and competition (alone vs. competition). Invasive plants produced more gibberellic acid, and grew larger than native species. Nutrient enrichment caused a greater increase in total biomass of invasive plants than of native plants, especially in the absence of competition or without simulated herbivory treatment. Nutrient enrichment decreased leaf flavonoid contents of invasive plants under both simulated herbivory conditions, but increased flavonoid of native plants under simulated herbivory condition. Nutrient enrichment only decreased tannins production of invasive species under competition. For native species, it enhanced their tannins production under competition, but decreased the chemicals when growing alone. The results indicate that the higher biomass production and lower flavonoids production in response to nutrient addition may lead to competitive advantage of invasive species than native species.

scholarly journals Micro-habitat and season dependent impact of the invasive Impatiens glandulifera on native vegetation

NeoBiota ◽  
2020 ◽  
Vol 57 ◽  
pp. 109-131
Author(s):  
Judith Bieberich ◽  
Heike Feldhaar ◽  
Marianne Lauerer
Keyword(s):  
Environmental Conditions ◽  
Native Species ◽  
Invasive Plant ◽  
Habitat Type ◽  
Context Dependency ◽  
Native Vegetation ◽  
Native Plant ◽  
Habitat Types ◽  
Impatiens Glandulifera ◽  
The Impact

The impact of invasive species is often difficult to assess due to species × ecosystem interactions. Impatiens glandulifera heavily invaded several habitat types in Central Europe but its impact on native plant communities is rated ambiguously. One reason could be that the impact differs between habitat types or even between environmentally heterogeneous patches (micro-habitats) within one habitat type. In the present study a vegetation survey was performed within heterogeneous riverside habitats in Germany investigating the impact of I. glandulifera on native vegetation in dependence of environmental conditions. The vegetation was recorded in summer and spring because of seasonal species turnover and thus potentially different impact of the invasive plant. We found that the cover of I. glandulifera depended on environmental conditions resulting in a patchy occurrence. I. glandulifera did not have any impact on plant alpha-diversity but reduced the cover of the native vegetation, especially of the dominant species. This effect depended on micro-habitat and season. The native vegetation was most affected in bright micro-habitats, especially those with a high soil moisture. Not distinguishing between micro-habitats, plant species composition was not affected in summer but in spring. However, environmental conditions had a higher impact on the native vegetation than I. glandulifera. We conclude that within riparian habitats the threat of I. glandulifera to the native vegetation can be rated low since native species were reduced in cover but not excluded from the communities. This might be due to patchy occurrence and year-to-year changes in cover of I. glandulifera. The context-dependency in terms of micro-habitat and season requires specific risk assessments which is also an opportunity for nature conservation to develop management plans specific to the different habitats. Particular attention should be given to habitats that are bright and very wet since the effect of I. glandulifera was strongest in these habitats.

scholarly journals Native Species Abundance Buffers Non-Native Plant Invasibility following Intermediate Forest Management Disturbances

2019 ◽  
Vol 65 (3) ◽  
pp. 336-343 ◽  
Author(s):  
Donald P Chance ◽  
Johannah R McCollum ◽  
Garrett M Street ◽  
Bronson K Strickland ◽  
Marcus A Lashley
Keyword(s):  
Species Richness ◽  
Loblolly Pine ◽  
Native Species ◽  
Biotic Resistance ◽  
Species Abundance ◽  
Data Sets ◽  
Native Plant ◽  
Species Abundances ◽  
Intermediate Disturbances ◽  
Native Species Richness

Abstract The biotic resistance hypothesis (BRH) was proposed to explain why intermediate disturbances lead to greater resistance to non-native invasions proposing communities that are more diverse provide greater resistance. However, several empirical data sets have rejected the BRH because native and non-native species richness often have a positive relation. We tested the BRH in a mature loblolly pine (Pinus taeda) forest with a gradient of disturbance intensities including canopy reduction, canopy reduction + fire, and canopy reduction + herbicide and fire. We analyzed data from the study using a combination of Pearson’s correlation and beta regressions. Using species richness, we too would reject BRH because of a positive correlation in species richness between native and non-native plants. However, native species abundance was greatest, and non-native species abundance was lowest following intermediate disturbances. Further, native and non-native species abundances were negatively correlated in a quadratic relation across disturbance intensities, suggesting that native species abundance, rather than richness, may be the mechanism of resistance to non-native invasions. We propose that native species abundance regulates resistance to non-native invasions and that intermediate disturbances provide the greatest resistance because they promote the greatest native species abundance.

Sign in / Sign up

Export Citation Format

Share Document