Niche Models Differentiate Potential Impacts of Two Aquatic Invasive Plant Species on Native Macrophytes

Potamogeton crispus (curlyleaf pondweed) and Myriophyllum spicatum (Eurasian watermilfoil) are widely thought to competitively displace native macrophytes in North America. However, their perceived competitive superiority has not been comprehensively evaluated. Coexistence theory suggests that invader displacement of native species through competitive exclusion is most likely where high niche overlap results in competition for limiting resources. Thus, evaluation of niche similarity can serve as a starting point for predicting the likelihood of invaders having direct competitive impacts on resident species. Across two environmental gradients structuring macrophyte communities—water depth and light availability—both P. crispus and M. spicatum are thought to occupy broad niches. For a third dimension, phenology, the annual growth cycle of M. spicatum is typical of other species, whereas the winter-ephemeral phenology of P. crispus may impart greater niche differentiation and thus lower risk of native species being competitively excluded. Using an unprecedented dataset comprising 3404 plant surveys from Minnesota collected using a common protocol, we modeled niches of 34 species using a probabilistic niche framework. Across each niche dimension, P. crispus had lower overlap with native species than did M. spicatum; this was driven in particular by its distinct phenology. These results suggest that patterns of dominance seen in P. crispus and M. spicatum have likely arisen through different mechanisms, and that direct competition with native species is less likely for P. crispus than M. spicatum. This research highlights the utility of fine-scale, abundance-based niche models for predicting invader impacts.

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Closed-Canopy Tropical Forests of Hainan, (China) Are Resilient against Invasive Herbs and Shrubs

Forests ◽

10.3390/f12111596 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1596

Author(s):

Xiaobo Yang ◽

Long Li ◽

Xiaobo Lv ◽

Wenqi Luo ◽

Donghai Li ◽

...

Keyword(s):

Tropical Forests ◽

Invasive Plants ◽

Native Species ◽

Invasive Plant ◽

Soil Seed Bank ◽

Light Availability ◽

Successional Stage ◽

Sharp Drop ◽

Closed Canopy ◽

Successional Stages

The successful establishment of many plants in tropical forests often depends on species-specific adaptations related to light availability and forest successional stage. Species that are present in early successional stages generally do not occur in later successional stages. In this study, we documented the diversity, distribution, and abundance of terrestrial invasive plants across the (sub)tropical island of Hainan, China, and tested the germination of specific invasive plants in forested environments. In 97 transects positioned randomly across the island, we found nine invasive herb and shrub species were present in all human-modified habitats but not in intact forest interiors. In separate forest-specific transects, we documented a sharp drop in the abundance of invasive plants >5 m into the forest. High numbers of invasive plant seeds germinated from the soil seed bank sampled at the forest edge, but very few seeds germinated from soil sampled any distance into the forest. Finally, in experiments with four focal invasive plant species, overall germination rates were low; and much lower in shaded sites compared to full gap sites. In conclusion, our findings demonstrated that invasive herbs and shrubs do not yet form a serious threat to native species in the closed-canopy forests of Hainan.

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The Biology of Invasive Alien Plants in Canada. 4. Heracleum mantegazzianum Sommier & Levier

Canadian Journal of Plant Science ◽

10.4141/p05-158 ◽

2006 ◽

Vol 86 (2) ◽

pp. 569-589 ◽

Cited By ~ 28

Author(s):

Nicholas A. Page ◽

Ronald E. Wall ◽

Stephen J. Darbyshire ◽

Gerald A. Mulligan

Keyword(s):

British Columbia ◽

Urban Areas ◽

Native Species ◽

Invasive Plant ◽

Leaf Shape ◽

Herbarium Specimens ◽

Natural Ecosystems ◽

Alien Plant ◽

Invasive Alien Plant ◽

Heracleum Mantegazzianum

Heracleum mantegazzianum (giant hogweed) is an invasive alien plant of management concern in southern Canada where it has escaped from horticulture and established and spread in natural, ruderal, and agricultural ecosystems. It poses a threat to natural ecosystems and human health, and is also a weed in agricultural and urban areas. It is a member of the Carrot family (Apiaceae) and is closely related to the native species Heracleum maximum Bartram (cow-parsnip). It is a monocarpic perennial, which generally flowers in its 3rd or 4th year. Large size, leaf shape, dark reddish pigments in patches on stems and petioles, and fruit characteristics readily distinguish H. mantegazzianum from other plants in Canada. It is increasingly common in riparian areas, floodplains, and forest edges in or near urban areas in southwestern British Columbia and southern Ontario. Based on herbarium specimens, H. mantegazzianum was first recorded in Ontario in 1949, British Columbia in 1964, Nova Scotia in 1980, Quebec in 1990, and New Brunswick in 2000. The development of dense stands of H. mantegazzianum can also reduce the richness of native plants. Contact with H. mantegazzianum can cause phytophotodermatitis, a serious skin inflammation caused by UV photo-activation of furanocoumarins present in the sap. Control methods include herbicide application, mechanical cutting, and animal grazing, but strategies to address seed dispersal and re-establishment from dormant seed must also be adopted. Widespread establishment in southern Canada suggests that eradication is unlikely. However, range expansion and rapid population growth can be prevented through strategic management including public education. Key words: Giant hogweed, Heracleum mantegazzianum, Apiaceae, HERMZ, invasive plant, weed biology, furanocoumarins

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Plant-Soil Relationships ofBromus tectorumL.: Interactions among Labile Carbon Additions, Soil Invasion Status, and Fertilizer

Applied and Environmental Soil Science ◽

10.1155/2009/929120 ◽

2009 ◽

Vol 2009 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Robert R. Blank ◽

James A. Young

Keyword(s):

Native Species ◽

Control Strategies ◽

Carbon Sources ◽

Growth Cycle ◽

Invasive Potential ◽

Labile Carbon ◽

Available N ◽

Plant Soil ◽

Exotic Grass ◽

Carbon Additions

Invasion of western North America by the annual exotic grassBromus tectorumL. (cheatgrass) has been an ecological disaster. High soil bioavailability of nitrogen is a contributing factor in the invasive potential ofB. tectorum. Application of labile carbon sources to the soil can immobilize soil nitrogen and favor native species. We studied the interaction of labile carbon addition (sucrose), with soil invasion status and fertilizer addition on the growth ofB. tectorum. Soils were noninvaded (BNI) andB. tectoruminvaded (BI). Treatments were control, sucrose, combined fertilizer, and sucrose + fertilizer. The greenhouse experiment continued for 3 growth-cycles. After the 1st growth-cycle, sucrose addition reducedB. tectorumaboveground mass almost 70 times for the BI soil but did not significantly reduce growth in the BNI soil.B. tectorumaboveground mass, after the 1st growth-cycle, was over 27 times greater for BI control soils than BNI control soils. Although sucrose addition reduced soil-solution , tissue N was not significantly lowered, suggesting that reduction of soil available N may not be solely responsible for reduction inB. tectorumgrowth. Noninvaded soil inhibits growth ofB. tectorum. Understanding this mechanism may lead to viable control strategies.

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Specialist Insect Herbivore and Light Availability Do Not Interact in the Evolution of an Invasive Plant

PLoS ONE ◽

10.1371/journal.pone.0139234 ◽

2015 ◽

Vol 10 (9) ◽

pp. e0139234 ◽

Cited By ~ 3

Author(s):

Zhijie Zhang ◽

Xiaoyun Pan ◽

Ziyan Zhang ◽

Kate S. He ◽

Bo Li

Keyword(s):

Invasive Plant ◽

Light Availability ◽

Insect Herbivore ◽

Specialist Insect

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Synthesis and Physico-Chemical Evaluation of Polyurethane Microstructures for Transmembrane Delivery of Reynoutria japonica Extract

Materiale Plastice ◽

10.37358/mp.17.4.4919 ◽

2017 ◽

Vol 54 (4) ◽

pp. 651-654

Author(s):

Florina Ardelean ◽

Razvan Susan ◽

Florin Borcan ◽

Alina Moaca ◽

Diana Simona Antal ◽

...

Keyword(s):

Drug Delivery ◽

Invasive Plant ◽

Aqueous Solubility ◽

Japanese Knotweed ◽

Reynoutria Japonica ◽

Good Thermal Stability ◽

Starting Point ◽

First Results ◽

Polymer Microstructures ◽

Transmembrane Delivery

Polymer microstructures containing plant extracts are a novel technique used to increase the bioavailability of active agents with low aqueous solubility. Japanese knotweed (Reynoutria japonica) is an invasive plant with multiple biomedical properties. The aim of the present study was to obtain and characterize polyurethane microstructures used as a drug delivery system of a Japanese knotweed extract. The results indicate the obtaining of microstructures with an almost neutral pH, with sizes between 540 and 1134 nm, with a medium stability against the tendency to form clusters and a very good thermal stability. These first results present the potential of the obtained polyurethane microstructures as candidates for the transmembrane drug delivery of Japanese knotweed extracts, as a starting point for further bioactivity investigations.

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Do Habitats Show a Different Invasibility Pattern by Alien Plant Species? A Test on a Wetland Protected Area

Diversity ◽

10.3390/d12070267 ◽

2020 ◽

Vol 12 (7) ◽

pp. 267 ◽

Cited By ~ 1

Author(s):

Francesco Liccari ◽

Miris Castello ◽

Livio Poldini ◽

Alfredo Altobelli ◽

Enrico Tordoni ◽

...

Keyword(s):

Native Species ◽

Light Availability ◽

Null Model ◽

Biodiversity Loss ◽

Habitat Destruction ◽

Environmental Characteristic ◽

Alien Plant ◽

Probabilistic Sampling ◽

Ne Italy ◽

Alien Flora

Biological invasions are deemed to be the second most important global driver of biodiversity loss, right behind habitat destruction and fragmentation. In this study, we aimed at testing if community invasibility, defined as the vulnerability to invasion of a community, could be associated with the characteristics of a given habitat, as described by the composition and structure of its native species. Based on a probabilistic sampling of the alien flora occurring in the temperate wetland Lake Doberdò (Friuli Venezia Giulia region, NE Italy) and using a null-model-based approach, the observed occurrence of Invasive Alien Species (IAS) within sampling units was randomized within habitats. While testing the degree of invasibility for each habitat within the wetland, our null hypothesis postulated that habitats are equally invaded by IAS, as IAS can spread homogeneously in the environment thanks to their plasticity in functional traits that makes them able to cope with different ecological conditions. The obtained results comparing observed IAS frequencies, abundance and richness to those obtained by the null model randomizations show that, for all habitats, invasion was selective. Specifically, a marked preference for habitats with an intermediate disturbance level, a high nutrients level and a medium-high light availability was observed, while an avoidance was detected for habitats characterized by lower levels of nutrients and light availability or extreme conditions caused by prolonged submersion. This method allows us to provide useful information using a simple-to-run simulation for the management of the IAS threat within protected areas. Moreover, the method allows us to infer important ecological characteristics leading to habitat invasion without sampling the environmental characteristic of the habitats, which is an expensive operation in terms of time and money.

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Slash Pile Burn Scar Restoration: Tradeoffs between Abundance of Non-Native and Native Species

Forests ◽

10.3390/f11080813 ◽

2020 ◽

Vol 11 (8) ◽

pp. 813

Author(s):

Ian Sexton ◽

Philip Turk ◽

Lindsay Ringer ◽

Cynthia S. Brown

Keyword(s):

Plant Species ◽

Native Species ◽

Invasive Plant ◽

Chemical Properties ◽

Rocky Mountain ◽

Native Plant ◽

Burn Scar ◽

Native Plant Species ◽

Burned Areas ◽

Soil Scarification

The accumulation of live and dead trees and other vegetation in forests across the western United States is producing larger and more severe wildfires. To decrease wildfire severity and increase forest resilience, foresters regularly remove excess fuel by burning woody material in piles. This common practice could also cause persistent ecosystem changes such as the alteration of soil physical and chemical properties due to extreme soil heating, which can favor invasion by non-native plant species. The abundance and species richness of native plant communities may also remain depressed for many years after burning has removed vegetation and diminished propagules in the soil. This adds to the vulnerability of burned areas to the colonization and dominance by invasive species. Research into the use of revegetation techniques following pile burning to suppress invasion is limited. Studies conducted in various woodland types that investigated revegetation of pile burn scars have met with varying success. To assess the effectiveness of restoring pile burn scars in Rocky Mountain National Park, Colorado, we monitored vegetation in 26 scars, each about 5 m in diameter, the growing season after burning. Later that summer, we selected 14 scars for restoration that included soil scarification, seed addition, and pine duff mulch cover. We monitored the scars for four years, pre-restoration, and three years post-restoration and found that the cover of seeded species exceeded the surrounding unburned areas and unseeded controls. The restoration seeding suppressed cover of non-native species as well as native species that were not seeded during restoration. Our results suggest that restoration of pile burn scars could be a useful tool to retard the establishment of invasive plant species when there are pre-existing infestations near scars. However, this must be weighed against the simultaneous suppression of native species recruitment. Monitoring for periods more than three years will help us understand how long the suppression of native and non-native species by restoration species may persist.

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Developing minimal-input techniques for invasive plant management: perimeter treatments enlarge native grass patches

Invasive Plant Science and Management ◽

10.1017/inp.2020.9 ◽

2020 ◽

Vol 13 (2) ◽

pp. 108-113

Author(s):

Scott R. Abella ◽

Lindsay P. Chiquoine ◽

Jeremy M. Moss ◽

Eric D. Lassance ◽

Charles D. Schelz

Keyword(s):

Native Species ◽

Invasive Plant ◽

Native Plants ◽

Perennial Grass ◽

Climatic Conditions ◽

Plant Management ◽

Native Grasses ◽

Native Grass ◽

Invasive Plant Management ◽

Wide Ring

AbstractThere is a continual need for invasive plant science to develop approaches for cost-effectively benefiting native over nonnative species in dynamic management and biophysical contexts, including within predominantly nonnative plant landscapes containing only small patches of native plants. Our objective was to test the effectiveness of a minimal-input strategy for enlarging native species patches within a nonnative plant matrix. In Pecos National Historical Park, New Mexico, USA, we identified 40 native perennial grass patches within a matrix of the nonnative annual forb kochia [Bassia scoparia (L.) A.J. Scott]. We mechanically cut B. scoparia in a 2-m-wide ring surrounding the perimeters of half the native grass patches (with the other half as uncut controls) and measured change in native grass patch size (relative to pretreatment) for 3 yr. Native grass patches around which B. scoparia was cut grew quickly the first posttreatment year and by the third year had increased in size four times more than control patches. Treated native grass patches expanded by an average of 25 m2, from 4 m2 in October 2015 before treatment to 29 m2 in October 2018. The experiment occurred during a dry period, conditions that should favor B. scoparia and contraction of the native grasses, suggesting that the observed increase in native grasses occurred despite suboptimal climatic conditions. Strategically treating around native patches to enlarge them over time showed promise as a minimal-input technique for increasing the proportion of the landscape dominated by native plants.

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The influence of warming and biotic interactions on the potential for range expansion of native and nonnative species

AoB Plants ◽

10.1093/aobpla/plaa040 ◽

2020 ◽

Vol 12 (5) ◽

Author(s):

Betsy von Holle ◽

Sören E Weber ◽

David M Nickerson

Keyword(s):

Plant Species ◽

Range Expansion ◽

Species Interactions ◽

Native Species ◽

Invasive Plant ◽

Soil Microbes ◽

Enemy Release ◽

Native Plant ◽

Soil Pathogens ◽

Microbe Interactions

Abstract Plant species ranges are expected to shift in response to climate change, however, it is unclear how species interactions will affect range shifts. Because of the potential for enemy release of invasive nonnative plant species from species-specific soil pathogens, invasive plants may be able to shift ranges more readily than native plant species. Additionally, changing climatic conditions may alter soil microbial functioning, affecting plant–microbe interactions. We evaluated the effects of site, plant–soil microbe interactions, altered climate, and their interactions on the growth and germination of three congeneric shrub species, two native to southern and central Florida (Eugenia foetida and E. axillaris), and one nonnative invasive from south America (E. uniflora). We measured germination and biomass for these plant species in growth chambers grown under live and sterile soils from two sites within their current range, and one site in their expected range, simulating current (2010) and predicted future (2050) spring growing season temperatures in the new range. Soil microbes (microscopic bacteria, fungi, viruses and other organisms) had a net negative effect on the invasive plant, E. uniflora, across all sites and temperature treatments. This negative response to soil microbes suggests that E. uniflora’s invasive success and potential for range expansion are due to other contributing factors, e.g. higher germination and growth relative to native Eugenia. The effect of soil microbes on the native species depended on the geographic provenance of the microbes, and this may influence range expansion of these native species.

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Potential Phytotoxic Effect of Essential Oil of Non-Native Species Impatiens parviflora DC.

Plants ◽

10.3390/plants8070241 ◽

2019 ◽

Vol 8 (7) ◽

pp. 241 ◽

Cited By ~ 3

Author(s):

Jana Jurová ◽

Martina Matoušková ◽

Anna Wajs-Bonikowska ◽

Danuta Kalemba ◽

Marek Renčo ◽

...

Keyword(s):

Seed Germination ◽

Essential Oil ◽

Plant Species ◽

Native Species ◽

Root Elongation ◽

Invasive Plant ◽

Main Compound ◽

Impatiens Parviflora ◽

Phytotoxic Effect ◽

Dicot Species

Impatiens parviflora is non-native invasive plant species occupying large areas all over the Europe and threatens native communities by altering their species composition and reducing native biodiversity. The factor responsible for its spreading could be explained by releasing biochemical to the environment. On the other hands, high demand on secondary metabolites as potential source of new ecofriendly biocides could be beneficial. The analysis of I. parviflora essential oil (EO) led us to identify more than 60 volatiles. The main compound was hexahydrofarnesyl acetone, other dominant components were phytol, carvacrol, germacra-4(15),5,10(14)-trien-1-α-ol, and pentacosane. The potential phytotoxic effect of I. parviflora EO collected in two vegetation periods (summer and autumn) was evaluated on seed germination and root elongation of three dicot species (Raphanus sativus, Lepidum sativum, and Lactuca sativa) and on one monocot species (Triticum aestivum). The seed germination of only one dicot species, L. sativa, was affected by both EOs. In contrast, seed germination of monocot species T. aestivum was influenced only by the highest doses of EOs isolated from I. parviflora in autumn. The root elongation of tested plant species was less influenced by I. parviflora EOs. L. sativum showed sensitivity to one dose of EOs hydrodistilled in summer, while the monocot species was influenced by both EOs samples in highest doses. Our findings revealed that I. parviflora contained phenolics that were phytotoxic to the germination of some plant species, mainly at higher EOs doses, while root elongation of tested plants was not suppressed by essential oils.

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