Release from Above- and Belowground Insect Herbivory Mediates Invasion Dynamics and Impact of an Exotic Plant

The enemy-release hypothesis is one of the most popular but also most discussed hypotheses to explain invasion success. However, there is a lack of explicit, experimental tests of predictions of the enemy-release hypothesis (ERH), particularly regarding the effects of above- and belowground herbivory. Long-term studies investigating the relative effect of herbivores on invasive vs. native plant species within a community are still lacking. Here, we report on a long-term field experiment in an old-field community, invaded by Solidago canadensis s. l., with exclusion of above- and belowground insect herbivores. We monitored population dynamics of the invader and changes in the diversity and functioning of the plant community across eight years. Above- and belowground insects favoured the establishment of the invasive plant species and thereby increased biomass and decreased diversity of the plant community. Effects of invertebrate herbivores on population dynamics of S. canadensis appeared after six years and increased over time, suggesting that long-term studies are needed to understand invasion dynamics and consequences for plant community structure. We suggest that the release from co-evolved trophic linkages is of importance not only for the effect of invasive species on ecosystems, but also for the functioning of novel species assemblages arising from climate change.

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

Oecologia ◽

10.1007/s00442-015-3472-6 ◽

2015 ◽

Vol 180 (2) ◽

pp. 507-517 ◽

Cited By ~ 11

Author(s):

Tim Engelkes ◽

Annelein Meisner ◽

Elly Morriën ◽

Olga Kostenko ◽

Wim H. Van der Putten ◽

...

Keyword(s):

Plant Species ◽

Plant Community ◽

Native Plant ◽

Native Plant Species

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Climatic Factors, Reproductive Success and Population Dynamics in the Montane Vole Microtus Montanus

The UW National Parks Service Research Station Annual Reports ◽

10.13001/uwnpsrc.2005.3607 ◽

2005 ◽

Vol 29 ◽

pp. 49-51

Author(s):

Alita Pinter

Keyword(s):

Population Dynamics ◽

Reproductive Success ◽

Population Density ◽

Climatic Factors ◽

Small Rodents ◽

Microtus Montanus ◽

Small Measure ◽

Long Term Studies

A variety of hypotheses has been proposed to explain multiannual fluctuations in population density ("cycles") of small rodents (for reviews see Finerty 1980, Taitt and Krebs 1985). Doubtless, such cycles - known since antiquity (Elton 1942) - result from an interaction of a multitude of factors. However, the inability of extant hypotheses, alone or in combination, to explain the causality of cycles rests in no small measure with the fact that long-term studies of the phenomenon are notoriously uncommon.

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Tallgrass Prairie Responses to Management Practices and Disturbances: A Review

Agronomy ◽

10.3390/agronomy8120300 ◽

2018 ◽

Vol 8 (12) ◽

pp. 300 ◽

Cited By ~ 3

Author(s):

Pradeep Wagle ◽

Prasanna Gowda

Keyword(s):

Species Richness ◽

Soil Quality ◽

Plant Species ◽

Tallgrass Prairie ◽

Management Practices ◽

The United States ◽

N Fertilization ◽

Native Plant ◽

The Impact

Adoption of better management practices is crucial to lessen the impact of anthropogenic disturbances on tallgrass prairie systems that contribute heavily for livestock production in several states of the United States. This article reviews the impacts of different common management practices and disturbances (e.g., fertilization, grazing, burning) and tallgrass prairie restoration on plant growth and development, plant species composition, water and nutrient cycles, and microbial activities in tallgrass prairie. Although nitrogen (N) fertilization increases aboveground productivity of prairie systems, several factors greatly influence the range of stimulation across sites. For example, response to N fertilization was more evident on frequently or annually burnt sites (N limiting) than infrequently burnt and unburnt sites (light limiting). Frequent burning increased density of C4 grasses and decreased plant species richness and diversity, while plant diversity was maximized under infrequent burning and grazing. Grazing increased diversity and richness of native plant species by reducing aboveground biomass of dominant grasses and increasing light availability for other species. Restored prairies showed lower levels of species richness and soil quality compared to native remnants. Infrequent burning, regular grazing, and additional inputs can promote species richness and soil quality in restored prairies. However, this literature review indicated that all prairie systems might not show similar responses to treatments as the response might be influenced by another treatment, timing of treatments, and duration of treatments (i.e., short-term vs. long-term). Thus, it is necessary to examine the long-term responses of tallgrass prairie systems to main and interacting effects of combination of management practices under diverse plant community and climatic conditions for a holistic assessment.

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Long-term exposure to elevated CO2 enhances plant community stability by suppressing dominant plant species in a mixed-grass prairie

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1414659111 ◽

2014 ◽

Vol 111 (43) ◽

pp. 15456-15461 ◽

Cited By ~ 37

Author(s):

T. J. Zelikova ◽

D. M. Blumenthal ◽

D. G. Williams ◽

L. Souza ◽

D. R. LeCain ◽

...

Keyword(s):

Plant Species ◽

Plant Community ◽

Elevated Co2 ◽

Community Stability ◽

Mixed Grass Prairie ◽

Dominant Plant Species ◽

Mixed Grass

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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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Quantifying whether different demographic models produce incongruent results on population dynamics of two long-term studied rodent species

European Journal of Ecology ◽

10.1515/eje-2017-0003 ◽

2017 ◽

Vol 3 (1) ◽

pp. 18-26

Author(s):

Giovanni Amori ◽

Valentina De Silvestro ◽

Paolo Ciucci ◽

Luca Luiselli

Keyword(s):

Population Dynamics ◽

Population Density ◽

Population Size ◽

Myodes Glareolus ◽

Suitable Model ◽

Demographic Model ◽

Apodemus Flavicollis ◽

Demographic Models ◽

Long Term Studies

Abstract1. Population density (ind/ha) of long-term (>15 years) series of CMR populations, using distinct demographic models designed for both open and closed populations, were analysed for two sympatric species of rodents (Myodes glareolus and Apodemus flavicollis) from a mountain area in central Italy, in order to test the relative performance of various employed demographic models. In particular, the hypothesis that enumeration models systematically underestimate the population size of a given population was tested.2. Overall, we compared the performance of 7 distinct demographic models, including both closed and open models, for each study species. Although the two species revealed remarkable intrinsic differences in demography traits (for instance, a lower propensity for being recaptured in Apodemus flavicollis), the Robust Design appeared to be the best fitting model, showing that it is the most suitable model for long-term studies.3. Among the various analysed demographic models, Jolly-Seber returned the lower estimates of population density for both species. Thus, this demographic model could not be suggested for being applied for long-term studies of small mammal populations because it tends to remarkably underestimate the effective population size. Nonetheless, yearly estimates of population density by Jolly-Seber correlated positively with yearly estimates of population density by closed population models, thus showing that interannual trends in population dynamics were uncovered by both types of demographic models, although with different values in terms of true population size.

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The Horseshoe whip snake (Hemorrhois hippocrepis) on Ibiza: predator release in an invasive population

Amphibia-Reptilia ◽

10.1163/15685381-bja10039 ◽

2020 ◽

pp. 1-6

Author(s):

Elba Montes ◽

Mónica Feriche ◽

Esmeralda Alaminos ◽

Juan Manuel Pleguezuelos

Keyword(s):

Lower Incidence ◽

Enemy Release Hypothesis ◽

Invasion Success ◽

Enemy Release ◽

Source Population ◽

Invasive Population ◽

Breakage Rate ◽

Snake Predators ◽

Whip Snake ◽

Predator Release

Abstract The key to fighting a biological invasion may lie in understanding every variable that can explain its success. The Enemy Release Hypothesis (ERH) states that when an invader arrives to a new environment, the absence of its common enemies (predators, parasites and competitors) facilitates the invasion success. The Horseshoe whip snake (Hemorrhois hippocrepis) has been recently introduced from the Iberian Peninsula to the island of Ibiza, and it is currently threatening the only endemic vertebrate, the Ibiza wall lizard (Podarcis pityusensis). We hypothesized that the snake invasion success is caused by the absence of natural predators, and we checked the ERH by relating the tail breakage rate to predation pressure. The invasive population showed a much lower incidence of tail breakage than the source population, which is in agreement with the almost absence of snake predators among the Ibizan reduced and naïve native vertebrate community. These results confirm the ERH, and support the prolongation of invasive snake trapping campaigns.

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