Academic literature on the topic 'Reynoutria'

This paper deals with the Reynoutria × bohemica and Reynoutria japonica under conditions of the Czech Republic. It evaluates the impact of soil, weather conditions and various terms of harvest (autumn, spring) on the yield, dry matter content, phytomass loss, ash content, and basic elements content change in plants. Heavy metals content was determined in soil where plants were grown and consequently in plants themselves. The average yield of dry matter at the fully closed stands of Reynoutria japonica were 9.06 t/ha in autumn, Reynoutria × bohemica from 13.23 to 21.41 t/ha, according to the site. The yield losses within the winter period were found on average 42% for Reynoutria japonica and 34% for Reynoutria × bohemica. The moisture decrease of Reynoutria japonica was found from 68% in the autumn to 24% in the spring, and of Reynoutria × bohemica from 67% to 23%, respectively. Decreased content of nitrogen, phosphorus, potassium, calcium, and magnesium in the knotweed phytomass was found during the latter (spring) harvest periods in comparison with the earlier harvest periods. Decreased elements content in phytomass during the latter harvest period (spring) increases the phytomass quality as a fuel from both aspects – technical and emissions generation. The ash content in plants varied according to the site, on average from 3.12% in Ruzyně to 4.6% in Chomutov. None of the heavy metals monitored in knotweed plants reached the maximum admissible values determined for the food or feed purposes in the Czech Republic. From the results of combustion experiments, it is evident that Reynoutria × bohemica is a good fuel. Energy sorrel shows the extreme CO concentration in flue gases in comparison with other monitored fuels. According to the ČSN EN 12809 (2001) standard it does not meet even the third class of requirements. On the contrary, knotweed and wood bark fulfill the requirements for the first class. The surprising fact is that both of these fuels show the lower level of CO emissions, than the wooden briquettes. Concentrations of nitrogen oxids are comparable with biofuels, except of wood, and probably are related to the nitrogen content in heating material.

This study was conducted to determine whether nature-derived Reynoutria elliptica extracts exhibit biocompatibility and antimicrobial effects against oral pathogens such as Streptococcus mutans and Candida albicans. Fine particles of Reynoutria elliptica extract were used to probe for biocompatibility and antimicrobial activity toward these pathogens, and results were evaluated with an MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay, spectrophotometric growth inhibitory assay, the total number of colony-forming units (CFU), an agar disk diffusion test, and scanning electron microscopy (SEM). In addition, UV/VIS spectroscopy was used to determine the levels of flavonoid and polyphenol in experimental solutions. Several experimental groups showed cell viability higher than 70%, and the antimicrobial activity toward both S. mutans and C. albicans was significantly higher than was that seen for the control group. In CFU and agar disk diffusion tests with C. albicans, increases in the concentration of Reynoutria elliptica extract led to significantly increased antimicrobial effects. Additionally, SEM results showed that Reynoutria elliptica extract changed the morphology and density of S. mutans and C. albicans. The results of this research can be applied to the use of Reynoutria elliptica extracts for the development of oral products that are biologically friendly and can control oral diseases such as dental caries and candida-associated denture stomatitis.

Extreme weather and globalisation leave our climate vulnerable to invasion by alien species, which have negative impacts on the economy, biodiversity, and ecosystem services. Rapid and accurate identification is key to the control of invasive alien species. However, visually similar species hinder conservation efforts, for example hybrids within the Japanese Knotweed complex. We applied the novel method of ATR-FTIR spectroscopy combined with chemometrics (mathematics applied to chemical data) to historic herbarium samples, taking 1580 spectra in total. Samples included five species from within the interbreeding Japanese Knotweed complex (including three varieties of Japanese Knotweed), six hybrids and five species from the wider Polygonaceae family. Spectral data from herbarium specimens were analysed with several chemometric techniques: support vector machines (SVM) for differentiation between plant types, supported by ploidy levels; principal component analysis loadings and spectral biomarkers to explore differences between the highly invasive Reynoutria japonica var. japonica and its non-invasive counterpart Reynoutria japonica var. compacta; hierarchical cluster analysis (HCA) to investigate the relationship between plants within the Polygonaceae family, of the Fallopia, Reynoutria, Rumex and Fagopyrum genera. ATR-FTIR spectroscopy coupled with SVM successfully differentiated between plant type, leaf surface and geographical location, even in herbarium samples of varying age. Differences between Reynoutria japonica var. japonica and Reynoutria japonica var. compacta included the presence of two polysaccharides, glucomannan and xyloglucan, at higher concentrations in Reynoutria japonica var. japonica than Reynoutria japonica var. compacta. HCA analysis indicated that potential genetic linkages are sometimes masked by environmental factors; an effect that can either be reduced or encouraged by altering the input parameters. Entering the absorbance values for key wavenumbers, previously highlighted by principal component analysis loadings, favours linkages in the resultant HCA dendrogram corresponding to expected genetic relationships, whilst environmental associations are encouraged using the spectral fingerprint region. The ability to distinguish between closely related interbreeding species and hybrids, based on their spectral signature, raises the possibility of using this approach for determining the origin of Japanese knotweed infestations in legal cases where the clonal nature of plants currently makes this difficult and for the targeted control of species and hybrids. These techniques also provide a new method for supporting biogeographical studies.

AbstractGiant knotweeds of the genus Reynoutria (syn. Fallopia)–Reynoutria japonica, Reynoutria sachalinensis, and a hybrid of them, Reynoutria x bohemica–are noxious invasive plants in Europe and North America. R. japonica is a traditional East Asian (Japan and China) drug (Polygoni cuspidati rhizoma). Recently, it has been included in European Pharmacopoeia as one of the traditional Chinese medicinal herbs. In this study, a reversed-phase high performance liquid chromatography method with diode array detector and time-of-flight mass spectrometry was developed and validated for the profiling of rhizomes from European invasive populations and Polygoni cuspidati rhizoma purchased in China. Twenty-five compounds were identified, mainly stilbenes, anthraquinones, flavan-3-ols, and phenylpropanoid esters. Tatariside B, hydropiperoside, vanicoside C, a new compound (3,6-O-di-p-coumaroyl)-β-fructofuranosyl-(2 → 1)-(2′-O-acetyl-6′-O-feruloyl)-β-glucopyranoside) were reported for the first time in these raw materials. Six compounds from three phytochemical classes–stilbenes: piceid and resveratrol; anthraquinones: emodin and physcion; hydroxycinnamic sucrose esters: vanicosides A and B–were quantified using the validated method. R. japonica from China contained twice as many stilbenoids than samples from Poland (piceid 14.83 mg/g dm vs. 7.45 mg/g and resveratrol 1.29 mg/g vs. 0.65 mg/g). R. sachalinensis rhizomes contained lower quantities of anthraquinones and no detectable stilbenes, which together with higher amounts of hydroxycinnamic glycosides makes it easily distinguishable from the other two. The phytochemical profile of R. x bohemica was intermediate between the two parent species.

The rhizome of Reynoutria japonica is a well-known traditional herb (Hu zhang) used in East Asia to treat various inflammatory diseases, infections, skin diseases, scald, and hyperlipidemia. It is also one of the richest natural sources of resveratrol. Although, it has been recently included in the European Pharmacopoeia, in Europe it is still an untapped resource. Some of the therapeutic effects are likely to be influenced by its antioxidant properties and this in turn is frequently associated with a high stilbene content. However, compounds other than stilbenes may add to the total antioxidant capacity. Hence, the aim of this research was to examine rhizomes of R. japonica and the less studied but morphologically similar species, R. sachalinensis and R. x bohemica for their phytochemical composition and antioxidant activity and to clarify the relationship between the antioxidant activity and the components by statistical methods. HPLC/UV/ESI-MS studies of three Reynoutria species revealed 171 compounds, comprising stilbenes, carbohydrates, procyanidins, flavan-3-ols, anthraquinones, phenylpropanoids, lignin oligomers, hydroxycinnamic acids, naphthalenes and their derivatives. Our studies confirmed the presence of procyanidins with high degree of polymerization, up to decamers, in the rhizomes of R. japonica and provides new data on the presence of these compounds in other Reynoutria species. A procyanidin trimer digallate was described for the first time in, the studied plants. Moreover, we tentatively identified dianthrone glycosides new for these species and previously unrecorded phenylpropanoid disaccharide esters and hydroxycinnamic acid derivatives. Furthermore, compounds tentatively annotated as lignin oligomers were observed for the first time in the studied species. The rhizomes of all Reynoutria species exhibited strong antioxidant activity. Statistical analysis demonstrated that proanthocyanidins should be considered as important contributors to the total antioxidant capacity.

AbstractKnotweed species in the genus Reynoutria are native to eastern Asia but have become noxious weeds in Europe and North America. In the United States, invasive populations of Japanese knotweed (Reynoutria japonica Houtt.), giant knotweed [Reynoutria sachalinensis (F. Schmidt) Nakai], and their interspecific hybrid known as Bohemian knotweed (R. × bohemica Chrtek & Chrtková) continue to expand their ranges. Although these plants are among the most invasive terrestrial species, there are relatively few molecular tools for identifying the parental species, the F1 hybrid, or subsequent hybrids or introgressed individuals. We studied Reynoutria populations in Wisconsin, a state where all three taxa grow, to determine whether molecular data would be useful for distinguishing species and identifying hybrids. We obtained DNA sequence data from the plastid matK gene and the nuclear LEAFY gene and compared these to previously published sequences. Data from the uniparentally inherited matK region included haplotypes attributable to R. japonica and R. sachalinensis. Nuclear data indicated that R. sachalinensis plants are most similar to native plants in Japan, with two Wisconsin accessions exhibiting a monomorphic genotype for the LEAFY gene. Three Wisconsin accessions of R. japonica were each characterized by having three distinct kinds of LEAFY sequence. Most plants in our study were found to possess two or three phylogenetically distinct copies of the LEAFY gene, with the copies being most closely related to R. japonica and R. sachalinensis, respectively, and these were inferred to be interspecific hybrids. Altogether, five kinds of interspecific hybrids were identified, reflecting various combinations of LEAFY sequence types from the parental species. The widespread existence of hybrid plants in Wisconsin, many of which are morphologically identifiable as R. japonica, indicates a cryptic genetic diversity that should be examined more broadly in North America using molecular tools.

The paper presents the results of several years investigations (2003-2007) on two invaders: the Himalayans <em>Impatiens glandulifera</em> and Asiatic <em>Reynoutria japonica</em>. The Sudety Mountains and their national parks are under strong pressure of both species, threatening the local vegetation. The four-year investigations have been carried out in field, glasshouse and in laboratory. Invasive species have their peculiar life histories which help them to occupy new areas. Those are above all the specific generative reproduction strategies (<em>Impatiens</em>) or vegetative reproduction strategies (<em>Reynoutria</em>). Both strategies secure the reproductive success and to capture more and more highly situated areas of the mountains. Very significant characteristics connected with the expansion of invaders is the excessively over and above the average production of seeds (<em>Impatiens</em>) and a huge annual increment aboveground biomass (<em>Reynoutria</em>). The investigated invasive species are probably not equipped with influence of allelopatic type as of greater importance is their competitive strength. The invaders can eliminate a part of the early spring flora belonging to the geophyte group and impoverish the regional biological diversity. Both the invasive plants enter also into some moist mountain forest communities.

Hoten mot den biologiska mångfalden är många men kan delas in i tre huvudkategorier: biotopförstörelse, överexploatering och införsel av främmande arter. Främmande eller invasiva arter är arter som introducerats till en plats av människan och som orsakar stora problem för den inhemska biologiska mångfalden som redan existerar på platsen. Parkslide (Reynoutria japonica) är en av de arter som idag räknas som mest invasiv och skapar stora problem för den biologiska mångfalden och samhället. Parkslide har ett aggressivt rotsystem som sprider sig över stora ytor och snabbt utplånar allt som växer i anslutning till den.Syftet med studien var att i samarbete med Örnborg Kyrkander biologi & miljö AB, utarbeta åtgärdsmetoder mot Parkslide samt att studera hur stora rhizomfragment av arten behövde vara för att tillväxa. Studien delades upp i Studie A och B, där studie A undersökte rhizomfragmentens tillväxt. Studie B utförde åtgärdsförsök på Parkslide med hjälp av åtgärdsmetoderna: salt, ättika (24%) samt såpa. Resultatet för studie A visar att det finns skillnad i tillväxt mellan rhizomfragment på 1 cm och rhizomfragment på 3 cm, där 1 cm tillväxte 0% och 3 cm tillväxte 100%. Resultaten hos Studie B visade att salt var överlägsen som åtgärdsmetod och såpa minst effektiv.De resultat som studien lyckats få fram på kort tid bidrar på sikt till att en reducering av Parkslide skulle kunna vara möjlig, vilket kan vara till stor hjälp i skyddandet av de habitat som är speciellt viktiga för många arter och i slutändan för den biologiska mångfalden.

Bien moins médiatisées que la déforestation ou le changement climatique, les invasions biologiques n’en demeurent pas moins problématiques pour la conservation de nombreux écosystèmes ou le bon déroulement de nombreuses activités socio-économiques.Comprendre la façon dont les espèces exotiques envahissantes s’étendent dans les différents milieux qu’elles colonisent c’est permettre à la fois de mieux appréhender leurs impacts, de pouvoir de prédire leur expansion, et de trouver les endroits stratégiques où agir pour contrer ou atténuer les effets indésirables de ces espèces. Le problème est que dynamiques d’invasions d’une espèce regroupent en fait une hiérarchie de processus se produisant simultanément à différentes échelles spatiotemporelles et qui sont contrôlés par des facteurs qui changent en fonction du temps et du contexte d’invasion. Pour acquérir une compréhension profonde de ces dynamiques, il faut donc étudier leurs manifestations et leurs causes aux diverses échelles spatiales et temporelles auxquelles elles se produisent.Présentes sur les cinq continents et très envahissante sur au moins deux, les renouées asiatiques (Reynoutria spp.) sont reconnues comme faisant partie des espèces les plus invasives de la planète. Dotées d’une grande tolérance environnementale et d’importantes capacités de multiplication végétatives, ces plantes herbacées géantes peuvent former rapidement de grandes monocultures clonales qui excluent les autres espèces végétales, modifient les cycles biogéochimiques des zones envahies et perturbent diverses activités anthropiques. Cibles de campagnes de gestion depuis des décennies, elles affichent cependant une résilience insolente qui désespère de nombreux gestionnaires. Bien que très étudiées, de nombreux détails concernant leurs dynamiques nous échappent toujours. Dans ce travail de thèse, nous avons donc cherché à identifier quels sont les facteurs qui contrôlent les dynamiques spatiotemporelles des renouées à différentes échelles, et comment une meilleure compréhension de ces dynamiques clés pourrait profiter à leur gestion ?Pour ce faire, nous nous sommes donc d’abord intéressés à leur dynamiques clonales et à leurs variations en fonction de différentes conditions de stress (ombrage) ou de perturbation (fauchage répétée). Nous avons montré que si les renouées sont bien affectées par des conditions stressantes ou perturbées, cela ne les empêche ni de s’établir, ni de croître. En fait, les renouées semblent pouvoir adopter différentes stratégies de croissance pour pallier ces contraintes, soulevant différentes questions liées à la gestion. Dans une deuxième étude, nous avons cherché quels étaient les variables qui expliquaient l’expansion des taches de renouées le long d’un gradient altitudinal. Si nous avons montré que les dynamiques d’expansion des taches étaient principalement contrôlées par leur taille (et donc potentiellement leur âge) ainsi que par la proximité de routes et de rivières, nous avons également apporté des indices qui suggèrent que les renouées pourraient être potentiellement capables d’envahir les montagnes. Ensuite, pour tenter d’aider à résoudre le problème de l’acquisition des données de distribution des renouées à large échelle, nous avons développé une méthode pour détecter et cartographier les populations de renouées à partir d’images satellites et issues de drones. Notre méthode a montré des résultats encourageants et celle-ci pourrait être utile à l’étude des invasions ainsi qu’à la détection des nouveaux foyers d’invasion pour une gestion plus précoce et efficace des renouées.Enfin, nous avons tenté de dresser un portrait global de la compréhension actuelle des dynamiques d’invasion des renouées en réalisant, en guise de discussion, une grande revue de littérature sur les mouvements de ces plantes à travers les échelles spatiales et temporelles et en y intégrant les apports des autres travaux de cette thèse
Although less mediatized than deforestation or climate change, biological invasions remain problematic for the conservation of many ecosystems and the maintenance of various socio-economical activities.Understanding the way invasive non-native species spread in their introduced range is enabling a better apprehension of their impacts, the possibility to predict their expansion, and the development of better management strategies. A problem is that a species invasion dynamics are actually composed of a hierarchy of processes occurring simultaneously at various spatiotemporal scales and which are controlled by drivers that are time- or context-dependent. To gain more profound insights into these dynamics, one has to study the patterns they create and their underlying processes at all relevant scales.Occurring on the five continents and highly invasive on at least two of them, Asian knotweeds (Reynoutria spp.) are acknowledged as being among the most invasive species in the world. Gifted with a large environmental tolerance and high abilities for vegetative multiplication, these giant herbaceous plants can quickly form large clonal monocultures that exclude the other plant species, modify biogeochemical cycles, and affect various anthropic activities. Target of management campaigns for decades, knotweeds display an insolent resilience to the great despair of many stakeholders. Despite having been extensively studied, many aspects of their dynamics are still elusive. Consequently, in this thesis, we have tried to highlight what the drivers of the spatiotemporal dynamics of knotweeds across scales are, and how their management could benefit from a better understanding of these dynamics?To answer these questions, we first focused our attention on the clonal dynamics of knotweeds and on their variations when they experience differing conditions in terms of light availability and disturbance (repeated mowing). We have shown that although shade or mowing affects the vigour and the development of clones, it does not prevent their establishment or their growth. In fact, knotweeds seem able to adopt different growth strategies to cope with environmental heterogeneity, suggesting some management avenues. In a second study, we tried to identify the drivers that controlled the expansion of knotweed stands along an elevational gradient. If we showed that the lateral expansion of stands is mostly constrained by their size (and thus, possibly their age) and the vicinity of roads and rivers, we also brought evidences that knotweeds could have the potential to invade mountain regions. Then, to help for the acquisition of large-scale datasets on knotweeds’ distribution, we developed a procedure to accurately detect and map knotweeds using satellite or drone imagery. Our results were quite encouraging and could be useful to both the basic research and to the detection of newly invaded areas, enabling earlier control operations and more efficient management.Finally, we tried to draw a full picture of the current knowledge on the invasion dynamics of knotweeds by reviewing the literature on the movement of these plants across spatial and temporal scales, to discuss and expand the reach of the insights gained in the various chapters of this thesis

The distribution of R. japonica and I. glandulifera on river banks within the Welsh Region of the National Rivers Authority is described. R. japonica and I. glandulifora were found to be widespread along most of the rivers in the region, occurring on 84% and 71% respectively of the rivers surveyed. The distribution of R. japonica on selected rivers was also investigated in relation to land use. The results showed that on riparian wasteground and land drainage works, R. japonica occurred more frequently than expected and at a higher abundance: on grazed land or in natural/semi-natural communities of river banks it occurred less frequently and in low abundance. The results of a general soil survey to describe the nutrient status of soils on which both species typically grew in South Wales are presented. The survey results suggested that both species are capable of growing on fertile and relatively infertile soils, although from the sites sampled, I. glandulifera tended to exist in nature on soils with a higher nitrogen and phosphorus content than R. japonica. Aspects of the ecology of R. japonica were investigated, these included (i) above-ground growth analysis at open and shaded sites; (ii) below-ground growth measurements (expansion of clumps and growth of rhizomes); and (iii) rhizome fragment viability. R. japonica responded to shade with reduced biomass and stem height, and an increased Leaf Area Ratio compared with plants grown at open sites. These responses were consistent during the two years when observations were made (1988 and 1990). Clump expansion (expressed as radius of the clump) was independent of clump size, but dependent on environmental conditions. Cutting clumps down increased the lateral spread of the plant relative to the uncut clumps. Rhizome fragments of ≥ 7.8g (wet weight) were viable and produced shoots above-ground within 50 days. Aspects of the ecology of I. glandulifera were also investigated, these included (i) growth analysis in open and shaded sites; (ii) germination of seedlings; (iii) seedling mortality; (iv) effect of plant density on seed production; and (v) seed dispersal. I. glandulifera responded to shade with reduced biomass (but similar Relative Growth Rates and stem heights) compared with plants growing at the open sites. Seeds collected from plants of I. glandulifera had high ( > 79%) germination success, and were mostly dispersed within 3.5m of the parent stand. Seedling mortality was density dependent within the range measured in the study (80-300 plants m⁻²). Increased plant density also resulted in reduced seed production per plant. A simple model to describe temporal population changes using the results from investigations (ii) to (v) above was developed. The model simulated population changes in numbers of adult plants over a 10 year period. Field trials were conducted to assess quantitatively the effectiveness of foliar applications of non-persistent herbicides (approved for use in or near water courses) at controlling riparian stands of both species. The results suggested that one application of 2,4-D amine at 2790g active ingredient ha⁻¹ early in the season (May-June) would control I. glandulifera and prevent the development of a viable seed bank. Two applications per season at the same dose using 2,4-D amine or glyphosate with 2154 g a.i. ha⁻¹ would control R. japonica, but 2,4-D amine was preferable because it allowed grass swards to persist after treatment. The extent to which treated stands might recover in succeeding years has not been established and needs further study. On the banks of the River Cynon, Aberdare, South Wales, seven designs of flood revetment blocks were tested for resistance to penetration and displacement by R. japonica. With the subsequent failure of all designs tested, the development and testing of a new block is described. Its success is attributed to a microporous structure and interlocking/overlapping edges. The invertebrates associated with the foliage and litter of two introduced (R. japonica and I. glandulifera) and two indigenous (Urtica dioica and Epilobium hirsutum) species were surveyed in May, July and September 1988 to provide comparative estimates of family diversity, and attempt to assess the likely conservation impact of these introduced plants where they are widespread and abundant. The invertebrate faunal assemblages associated with the foliage of the two introduced species were impoverished relative to the foliage of the two native species sampled, with fewer taxa and fewer individuals. In the leaf litter the effect of the introduced plant species was less marked, with numbers of animals and taxa being reduced in the September samples only. An initial assessment of the flooding hazard, which R. japonica represents on river banks, was made. The results suggested that flooding might occur September-October when living plants had a high biomass and river flows are relatively high. Local authority estimates are given for the cost of repairing damage caused by the plant and for its control. It was concluded that when control measures are undertaken costs are high, even when the affected areas are small, due in part to the continued management required in subsequent seasons to ensure eradication of the plant. Aspects of the study relevant to local authorities are discussed in relation to improved management practices which may prevent or restrict the spread of the plant more effectively. Opportunities for further research are outlined.

Technical-economical study of biofuel cultivation is the topic of this diploma thesis. This is a study that includes the technology of growing biomass and its subsequent treatment. Part of the work is an economic and sensitivity analysis, which aims to determine the price of produced biomass. This work focuses on herbal biofuels and their comparison with other types of fuels.

Reynoutria spp. rank among highly invasive taxa in the Czech Republic. Therefore, a considerable effort is focused on its eradication. This is usually done by application of non- selective herbicide based on glyphosate. However, only little is known about the spontaneous recovery of the native vegetation after the eradication, as well as whether the restoration can be facilitated by additional management. In my master thesis I (i) describe the process of restoration after Reynoutria spp. eradication, (ii) evaluate the influence of factors which could potentially inhibit the succession (such as glyphosate, allelopathy, changes in soil conditions due to Reynoutria spp. invasion), and (iii) evaluate the influence of native-species seed addition on establishment of target plant communities. The process of vegetation recovery was followed on 17 sites in a forest and in ruderal forest-free area from 2007 to 2010. Over the three years of the study, the sites in the forest- free area were covered by diverse vegetation, secondary succession on sites in a forest progressed more slowly. Any soil changes were detected. The process of succession was limited probably because a dead biomass was left on the sites after the eradication. The seed addition was also not crucial for the restoration of plant communitites.

Although it is widely recognized that exotic plant invaders can affect diversity of native plant communities, a few studies of natural systems concern about the nature abundance and diversity loss and the associated consequences for higher trophic levels. Little is known impact of exotic riparian plant on higher-order consumers, such as birds. Such is requirement to understand underlying mechanisms of invasive processes and formulating effective management strategies. We examined interaction between invasive knotweed (Reynoutria sp. div., next only knotweed) and bird communities. We recorded occurrence of birds along three rivers in riverbanks that were either dominated by native vegetation or invaded by knotweed. Birds were recorded in breeding seasons in 2011 and 2012 near town Frýdek-Místek and Valašské Meziříčí. We interested especially in (i) how knotweed composition within riparian systems affects avian communities and (ii) what common bird characteristics are influenced by knotweed. Our outcome found positive effect of Marsh Warbler (Acrocephalus palustris) and Great Tit (Parus major) in high knotweed cover and negative effect of Grey Wagtail (Motacilla cinerea). Interspecific comparison common avian characteristics suggest that knotweed invasion can impact avian abundance living in lower...

Abstract This chapter describes some of the more common weeds and invasive plants and methods to control them. Species mentioned include Alopecurus myosuroides, Pteridium aquilinum, Elymus repens, Cirsium arvense, Rumex obtusifolius, R. crispus, R × pratensis, Equisetum arvense, Ulex europaeus, U. gallii, U. minor, Reynoutria japonica, Senecio jacobaea, Juncus conglomeratus, J. effusus, and J. inflexus.

Didžioji rūgtis (Reynoutria sachalinensis) pasirinkta kaip perspektyvus energinis augalas, nes ji nėra reikli dirvožemiui ir dėl aukšto derlingumo priklauso patiems našiausiems centrinės Europos augalams. Dėl panašių mechaninių ir terminių savybių rūgtys prilyginamos medienos briketams ir granulėms. Jų produktyvumas – 15 t ha–1 sausos masės. Eksperimentiniai tyrimai buvo atlikti Aleksandro Stulginskio universiteto laboratorijose. Rūgčių ir drambliažolių bei sidų biomasė buvo nupjauta, susmulkinta, sumalta ir granuliuota mažos galios granuliatoriumi (200– 350 kg h–1). Buvo nustatyti techniniai biokuro paruošimo ir naudojimo parametrai. Drambliažolė (Miscanthus sinensis) ir sida (Sida hermaphrodita) buvo pasirinkti kaip kontroliniai augalai. Buvo nustatyta augalo pjaustinio ir frakcinė miltų sudėtis, taip pat granulių kokybės rodikliai – drėgnis, tankis, elementinė sudėtis, peleningumas ir šilumingumas. Drėgnis siekė 30,5 %, tankis – 1057,5 kg m–3, peleningumas – 4,3 %, o šilumingumas – 17,7 MJ kg–1.