Intraspecific Trait Variability Determines Understorey Plant Community Assembly

Increasing evidence points to the major impact of intraspecific variability in species characteristics on community assembly. Contrasting theories predict that high trait variability might either steepening dominance orders or promote diversity. Here, we try to test these predictions with understorey plants in a Polish mixed temperate forest. We focus on four important traits (leaf dry mass LDW, plant height SH, specific leaf area SLA, and number of flowers NF) of the small balsam Impatiens parviflora, the dominant species in this forest system. We relate trait variability to community species richness and abundances, as well as to soil characteristics. The variance – mean relationships of LDW, LH, and NF, but not of SLA, closely followed power functions with slopes > 1.5. Contrary to theory, abundances but not species richness of non-I. parviflora species significantly decreased within increasing variance in I. parviflora trait expression. High trait variability prevailed a higher species richness. Trait variability did not significantly influence species composition and was not significantly correlated with soil characteristics. Our results emphasis the need to study trait variability in terms of appropriate statistical standards as provided by the allometric variance - mean relationship. We argue that an individual based study of local trait variability might return important insights into the composition and assembly of local communities.

Impatiens parviflora (small balsam).

I. parviflora is an exceptionally successful invader of many European countries. Its spread has been rapid, it is abundant in many parts of its exotic range and is one of few plants to successfully invade undisturbed forest vegetation. It is consequently regarded as undesirable by some, though there is little evidence of negative economic, social or environmental impacts. Further spread in central Europe is not likely as the species is already very abundant. In North America, on the other hand, it is still very localized. Even without clear evidence for impacts, a further spread there should not be encouraged by deliberate or careless transport of the species.

Synanthropization of forest and shrub florocomplexes of the Middle Cis-Dnipro Region (Ukraine)

The information about the modern state synanthropization of forest and schrub floristic complexes of the Middle Cis-Dnipro Region (Ukraine) is generalized. The studies complexes recently have been significantly affected by anthropogenic influences and its consequences have led to a change in their floristic composition. The synanthropic fraction of the flora of studies floristic complexes is represent by 262 species of vascular plants, incl. 100 apophytes and 162 aliens. The results of fractional and structural analysis is presented. In the apophytic fraction, the largest number of species belongs to the families Asteraceae (23 species) and Caryophyllaceae (15); in this group are prevail: in the life forms spectra (according to K. Raunkier) – hemicryptophytes (52 sp.); in the hydromorphes spectra – xeromesophytes (36) and meso-xerophytes (32); according to the degree of adaptation of species to transformed ecotops – evapophytes (41) and hemiapophytes (38); by coenotic peculiarity – meadow (35). In the alien fraction, the largest number of species belong to the families Asteraceae (25) and Rosaceae (15); in this group are dominated by: species of North American (44) and Mediterranean (37) origin; according to the degree of naturalization – epoecophytes (64); in the life forms spectra – therophytes (54); in the hydromorphes spectra – mesophytes (75) and xeromesophytes (67). Annotation list of synanthropic fraction species, as well as apophytic and alien, is presented. A separate list of species of the forest and schrub complexes (46), which are able to extend to the transformed ecotopes outside the forest coenoses is presented. The predominance of adventization process over apophytization indicates a significant disruption of the structure of many plant communities. In the alien fraction a high percentage of species tree is observated. The most species as well as of apophytic and alien fractions of the studies complexes in the Region are characterized by high degree of naturalization and active and mass distribution. Some alien species, e.g. Amorpha fruticose, Acer negundo, and Impatiens parviflora etc. in the Region are transformer species, e.g., A. fruticosa is a characteristic species of F1.11 and G 1.112 biotopes; A. negundo dominates in coenosis of G1.35 biotope and formed of plant community in І4.111 and І4.12 biotopes, Impatiens parviflora – in G3.11 and G3.12 biotopes.

Comparative floral and pollen morphology of some invasive and native impatiens species

To evaluate the hypothesis of competitive superiority of invasive species, we compared the invasive Impatiens parviflora DC. and I. Glandulifera royle, the naturalized I. Nevskii pobed. and the native I. Noli-tangere L. in the flowers’ morphometric characters at different phases of anthesis. The characters in which alien species have a competitive superiority over closely related I. Noli-tangere are revealed. Morphological variability was studied by morphometric observations of the following characters: bud: length and diameter; spurred sepal: length and width; spur: length and diameter; lateral sepal: length and width; largest petal: length and death; large lobe of lateral petal: length and width; small lobe of lateral petal: length and width; anther: length; stamen’s filament: length; calyptra: length and width; ovary: length and diameter; length of a style, length of a stigma. There is a tendency for alien Impatiens species of the earlier development of androecium and gynoecium: сaliptra is formed at the stage of uncolored bud, the pistil is differentiated in ovary, short style and stigma is formed at the stage of colored bud. No other flowers’ morphometric characters, representing competitive advantage of the invasive I. Glandulifera and I. Parviflora over the native I. Noli-tangere and naturalized I. Nevskii were identified.

Sustainable Green Roof Ecosystems: 100 Years of Functioning on Fortifications—A Case Study

Green roofs have received much attention in recent years due to their ability to retain rainwater, increase urban diversity, and mitigate climate change in cities. This interdisciplinary study was carried out on three historical green roofs covering bunkers in Wrocław, located in southwestern Poland. It presents the results of a three-year investigation of the water storage of these roofs. The study also presents soil conditions and spontaneous vegetation after their functioning for over 100 years. The soils covering the bunkers are made of sandy, sandy-loam, and loamy-sand deposits. This historical construction ensures good drainage and runoff of rainwater, and is able to absorb torrential rainfall ranging from 100 to 150 mm. It provides suitable conditions for vegetation growth, and forest communities with layers formed there. In their synanthropic flora, species of European deciduous forests dominate, which are characteristic of fresh or moist and eutrophic soils with a neutral reaction. Some invasive species, such as Robinia pseudoacacia, Padus serotina, and Impatiens parviflora, also occur with high abundance. Nowadays, historical green roofs on fortifications, although they have lost their primary military role, are of historical and natural value. These roofs can promote the nonmilitary functions of historical fortifications in order to strengthen the ties between nature and heritage. Protecting and monitoring historical green roofs should be included in the elements of the process of sustainable development and the conservation of these structures in order to mitigate climate change in the outskirts of the city. For this, it is necessary to ensure proper conservational protection, which, in addition to maintaining the original structure, profiles, and layout of the building, should include protection of their natural value.

Az Oenothera pycnocarpa Atk. & Bartl. Magyarországon, és kiegészítések néhány idegenhonos faj hazai elterjedéséhez

A tanulmány 19 neofita faj 153 új elterjedési adatát tartalmazza Magyarország területéről az elmúlt néhány évből. Először sikerült kimutatni Magyarországról az Oenothera pycnocarpa-t, mely Tápiószecső határában, ugaron telepedett meg. Megadjuk a talált növények részletes morfológiai leírását, fotókkal illusztrálva. Európai példák alapján lassú terjedése várható, mely nem fenyegeti a természetes élőhelyeket átalakítással. Bemutatunk 3 átalakító fajt, melyek közül a Sporobolus cryptandrus homoki gyepeket veszélyeztet a Kiskunságban, a Prunus serotina a Bakonyalján tölgyes felújítások során jelent fokozódó problémát, míg a Panicum dichotomiflorum (elsősorban az Északi-középhegységben) gyorsuló ütemben alakítja át a mezőgazdasági területek gyomvegetációját és a mezsgyék, útszélek növényzetét. Részben átalakító fajok közül kettőt ismertetünk. Az Alföld kivételével, az ország nagy részén már igen elterjedt Impatiens parviflora alföldperemi, szigetszerű erdőfoltban való megjelenéséről számolunk be, valamint számos helyről mutatjuk ki az alulkutatott Oenothera depressa-t, mely az egyik leggyakoribb ligetszépe taxon a Kiskunságban, és főleg homoki parlagokon, meddőhányókon és törmelékdombokon, esetenként homoki gyepekben és kultúrerdők nyílt homokfelszínein él. Az Oenothera pycnocarpa-n kívül 10 további terjedő, de (még) nem átalakító fajról is közlünk adatokat. A Commelina communis jellegzetes városi előfordulásai mellett vasúti sínek között és erdei szemétkupacon is megjelent. A Cymbalaria muralis nagyobb városokon kívül már kisebb falvak kőfalain is megtalálható. Az Euphorbia maculata, E. prostrata és az Eleusine indica jellemző városi populációin kívül ma már falvakban és műutak, földutak településektől távoli pontjain is élnek. Az Iva xanthiifolia trágyadombon, szántóparlagon és vadszórókon került elő, lassan terjedő faj. A Lepidium densiflorum megjelenése földutakon és vasútállomásokon jellegzetes. A dísznövényként ültetett Oenothera glazioviana szubspontán állományai elsősorban faluszéli árokpartokon, szemétdombokon, ritkábban homoki parlagokon bukkannak fel és élnek túl. A Phytolacca esculenta gyorsuló invázióját zöldhulladék-dombi, árokparti és városi parki adatokkal dokumentáljuk. A Trigonella caerulea egykori takarmánynövény, mely homoki szántóparlagokon önfenntartó állományokat hozott létre Fülöpszállás határában. Végül bemutatunk 3 alkalmi kivadulót. Az Euphorbia lathyris és az Impatiens balfourii terjesztésében nagy szerepet játszanak az illegális zöldhulladék-dombok, a lerakott nyesedék. A világszerte is csak ritkán kivaduló Goniolimon tataricum szubspontán előfordulását a Balaton-felvidéken útrézsűkön, Kunszentmiklóson temetőben figyeltük meg.

Kenophytes in different forest types of Ukraine

The article aims to 1) describe the distribution of non-native species of vascular plants (only kenophytes, i. e. naturalized species introduced after the 15th century) in different types of forests and different biogeographical regions of Ukraine; 2) compare proportions of kenophytes in forests of different areas; 3) detect statistically significant changes in the occurrence of kenophytes over the last 80 years. The material consists of 2701 relevés sampled in 1990–2018. They were taken from Ukrainian phytocoenological publications and databases. In Ukraine, as in other European countries, the highest proportion of kenophytes (percentage of species number per relevé) is in floodplain forests (up to 9.1% in willow and poplar forests). The lowest proportion is characteristic for bog woods (0%) and most types of mountain forests. Among biogeographical regions, the highest values were found in the flatland areas of the Steppic region and the forest-steppe part of the Continental region. The most frequent species are Impatiens parviflora (predominantly in broadleaved woods, absent in relevés from the steppic biogeoregion) and Erigeron canadensis (pine woods on sand). Comparison with 1466 older relevés sampled in 1950–1989 allows us to make a conclusion that the proportion of kenophytes increased at least in one habitat type (oak-hornbeam forests).