Invasive plants form new ecological links with native biota that can affect soil animals. Giant goldenrod (Solidago gigantea Aiton) of the Asteraceae family originates in North America, but it is an ...invasive plant elsewhere in the world. We studied the belowground arthropod communities of invasive S. gigantea and native vegetation at three sites near Moscow, Russia. Molecular techniques allow for quick identification of the community composition but provide little information on the abundance of soil animals and should be verified by classical taxonomy methods. Thus, we identified soil arthropods using metabarcoding and morphological identification. The number of arthropod families identified by the two methods was comparable (53 and 56, respectively), with a significant correlation in the number of families detected in individual samples based on morphological and metabarcoding approaches. The structure of the belowground arthropod community was subtly different between the goldenrod and control sites. A goldenrod transplant experiment was designed to control the random factors that created site-specific variation. After one year, the abundance and diversity of soil arthropods remained the same in sites with transplanted goldenrod and the control plots, leading to the conclusion that invasive S. gigantea does not affect soil arthropod communities in this region.
Display omitted
•The effects of invasive Solidago gigantea on soil arthropod communities were explored.•Morphology-based and metabarcoding approaches were used for arthropod identification.•Soil arthropod communities did not differ between Solidago thickets and control sites.•Metabarcoding- and morphology-based approaches gave comparable results.
In a work that will interest researchers in ecology, genetics, botany, entomology, and parasitology, Warren Abrahamson and Arthur Weis present the results of more than twenty-five years of studying ...plant-insect interactions. Their study centers on the ecology and evolution of interactions among a host plant, the parasitic insect that attacks it, and the suite of insects and birds that are the natural enemies of the parasite. Because this system provides a model that can be subjected to experimental manipulations, it has allowed the authors to address specific theories and concepts that have guided biological research for more than two decades and to engage general problems in evolutionary biology. The specific subjects of research are the host plant goldenrod ( Solidago ), the parasitic insect Eurosta solidaginis (Diptera: Tephritidae ) that induces a gall on the plant stem, and a number of natural enemies of the gallfly. By presenting their detailed empirical studies of the Solidago-Eurosta natural enemy system, the authors demonstrate the complexities of specialized enemy- victim interactions and, thereby, the complex interactive relationships among species more broadly. By utilizing a diverse array of field, laboratory, behavioral, genetic, chemical, and statistical techniques, Abrahamson and Weis present the most thorough study to date of a single system of interacting species. Their interest in the evolutionary ecology of plant-insect interactions leads them to insights on the evolution of species interactions in general. This major work will interest anyone involved in studying the ways in which interdependent species interact.
Biological invasions are an important problem of human-induced changes at a global scale. Invasive plants can modify soil nutrient pools and element cycling, creating feedbacks that potentially ...stabilize current or accelerate further invasion, and prevent re-establishment of native species.
The aim of this study was to compare the effects of Reynoutria japonica, Rudbeckia laciniata and Solidago gigantea, invading non-forest areas located within or outside river valleys, on soil physical and chemical parameters, including soil moisture, element concentrations, organic matter content and pH. Additionally, invasion effects on plant species number and total plant cover were assessed. The concentrations of elements in shoots and roots of invasive and native plants were also measured. Split-plot ANOVA revealed that the invasions significantly reduced plant species number, but did not affect most soil physical and chemical properties. The invasions decreased total P concentration and increased N-NO3 concentration in soil in comparison to native vegetation, though the latter only in the case of R. japonica. The influence of invasion on soil properties did not depend on location (within- or outside valleys). The lack of invasion effects on most soil properties does not necessarily imply the lack of influence of invasive plants, but may suggest that the direction of the changes varies among replicate sites and there are no general patterns of invasion-induced alterations for these parameters. Tissue element concentrations, with the exception of Mg, did not differ between invasive and native plants, and were not related to soil element concentrations.
Display omitted
•Effects of three invasive plants on plant diversity and soil properties were analyzed.•Plant invasions considerably reduced plant diversity.•Most soil parameters were not influenced by plant invasions.•Plant invasions decreased total P and R. japonica increased N-NO3 content in soil.•Element concentrations in soil were poorly related to those in plant tissues.
This study assessed the effects of
Reynoutria japonica
,
Rudbeckia laciniata
, and
Solidago gigantea
invading sites within and outside river valleys on activity, biomass, and composition of soil ...microbial communities. Microbial properties such as soil respiration, urease and arylsulfatase activities, microbial biomass (based on substrate-induced respiration, or SIR, and phospholipid fatty acids, or PLFA), and community composition (based on PLFA) were determined.
R. japonica
encroached on sites characterized by the lowest values of microbiological properties and
R. laciniata
on sites with the highest microbiological quality. The effect of invasion on soil microbial properties depended on the invasive plant species.
R. japonica
significantly decreased microbial biomass, determined by both SIR and total PLFA, urease activity, fungal PLFA, fungal:bacterial PLFA ratio, gram-negative bacterial PLFA, and soil respiration in comparison to soil under adjacent native plant communities. Microbial community composition also differed between soils under
R. japonica
and those under native plants. In contrast,
R. laciniata
and
S. gigantea
did not influence most microbial properties, though
S. gigantea
significantly increased fungal PLFA and
R. laciniata
and
S. gigantea
increased fungal:bacterial PLFA ratio. The effects of plant invasion on microbial properties were basically similar in soils located within and outside river valleys, probably because initially (i.e., before invasion) soils from the two locations were largely similar in terms of basic properties such as texture, moisture, pH, C:N ratio, and most microbial properties.
We studied the effects of invasions by three plant species:
Reynoutria japonica
,
Rudbeckia laciniata
, and
Solidago gigantea
, on arbuscular mycorrhizal fungi (AMF) communities in habitats located ...within and outside river valleys. Arbuscular mycorrhizal colonization, AMF abundance and species richness in soils were assessed in adjacent plots with invaders and native vegetation. We also quantified the performance (expressed as shoot mass, chlorophyll fluorescence, and the concentration of elements in shoots) of two common, mycorrhizal native plants,
Plantago lanceolata
and
Trifolium repens
, grown in these soils. The invasions of
R. japonica
,
R. laciniata
, and
S. gigantea
influenced AMF communities compared to native vegetation, but the changes depended on the mycorrhizal status of invaders. The effects of non-mycorrhizal
R. japonica
were the most pronounced. Its invasion reduced AMF abundance and species richness. In the plots of both mycorrhizal plants,
R. laciniata
and
S. gigantea
, we observed decreased AMF species richness in comparison to native vegetation. The AMF community alterations could be due to (i) depletion of organic C inputs to AMF in the case of
R. japonica
, (ii) plant secondary metabolites that directly inhibit or selectively stimulate AMF species, or (iii) changes in soil physicochemical properties induced by invasions. The effect of invasion on AMF abundance and species richness did not generally differ between valley and outside-valley habitats. The invasions affected photosynthetic performance and the concentrations of elements in the shoots of
P. lanceolata
or
T. repens
. However, the directions and magnitude of their response depended on both species identity and the mycorrhizal status of invaders.
The experiment focused on feed evaluation was conducted with goats to determine the feeding value of two aggressive weeds, the giant goldenrod (Solidago gigantea) and the bushgrass (Calamagrostis ...epigejos). Studied plants at the pre bloom stage were evaluated for feeding value by 7-month-old castrated goats (n=5 per group, BW=25.0 kg). All animals received no supplemental feed. The two plants differed in content of dry matter (DM) (266 vs. 394 g/kg) as well as in crude protein (119 vs. 86g), crude fibre (222 vs. 317 g) and N-free extract (523 vs. 447 g) per kg DM. In this study, total daily DM intake from giant goldenrod and bushgrass was similar (666 vs. 689 g/goat). Apparent digestibility of these plants was similar for organic matter (58-59%), but differed for crude protein (71 vs 53%) and N-free extract (72-62%). The values of total digestible nutrients (55.9-53.4%), net energy for maintenance (NEm: 4.90-4.54 MJ) and net energy for lactation (NEl: 5.16-4.91 MJ) per kg DM were similar. The study concluded that Solidago gigantea and Calamagrostis epigejos aggressive plants could be interesting feed for goats due to their feeding values. In addition, both of these aggressive weeds are relatively easily available.
Interactions among native and invasive species may affect management outcomes and goals. We implemented different mowing regimes to control the invasive Solidago gigantea and restore natural ...diversity, and also examined interactions between Solidago and a European native competitor, Tanacetum vulgare in the context of these regimes. Experimentally planted Tanacetum suppressed Solidago by 79% without management, and a suite of mowing management regimes reduced the density of Solidago by 80–98% when Tanacetum was absent. But, when Tanacetum was added, the density of the invader was not reduced by mowing. Put another way, in mowed plots with Tanacetum, Solidago was twofold to over fivefold denser than in mowed plots without Tanacetum. It is not clear why the effect of Tanacetum shifted from competition in the absence of disturbance to facilitation with intense management‐associated disturbance, but other studies suggest that Tanacetum may create plant–soil feedbacks that favor Solidago. Evidence shows similar shifts from competition to facilitation under mowing regimes for other species, but these are not mechanistically clear either. We speculate that mowing reduced competition from Tanacetum while leaving belowground facilitative effects unchanged, shifting the net effect of Tanacetum to facilitation. When single‐year mowed plots were abandoned for just 1 year, Solidago was twofold denser than in the control, thus maintaining treatments over time was important for successful management. Our results indicate that mechanical control may substantially alter biotic resistance gained from native competition.
PDF
