Swamp Communities Research Articles

Wetland Vegetation Resources and Livelihood Outcomes of Yala Swamp Residents

Wetlands are highly productive ecosystems, providing several goods and services that are of value to people. Never the less, there is limited evidence to attest to this value especially in wetland areas of Kenya. The study was conducted to assess the effects of wetland vegetation use on community member’s livelihoods. The research design of the project was a descriptive survey with a sample of 200 participants drawn from households in Yala swamp area. Data was collected from a sample of 146 households using a structured questionnaire. This represented a 73.2% response rate, which was considered sufficient for analysis and inference. The study showed that the wetland vegetation use has a positive influence on both improved healthcare and nutrition of the Yala swamp community members. The study concluded that wetland vegetation resources played an important role in ensuring the community members’ livelihood outcomes through improved incomes, healthcare, and better nutrition. The study recommends that wetland resources should be protected otherwise, their key functions could be impaired when wetlands are lost or degraded.

MOSSES OF FOREST SWAMPS IN THE SOUTHERN WEST SIBERIA

Long-term bryological research in birch and spruce forest swamps in the southern periphery of West Siberia are resulted in summary list of 133 moss species. Constancy and ecological features are given for all the species; some examples are discussed. It is shown that birch and spruce forest swamps (background and rare types of communities for the study area), are approximately equal in the diversity of moss species, and 60% of the recorded species were found in both types of communities. On the latitudinal gradient from north to south, the number of moss species in the forest swamps of the southern taiga and subtaiga is approximately equal, further south it decreases and in the steppe zone it is reduced by more than half, to the set of 43 most widespread and constant species. It was revealed that in forest swamp communities only a few moss species have high occurrence rates (Plagiomnium ellipticum, Сlimacium dendroides, Calliergon cordifolium, Calliergonella cuspidata, Drepanocladus aduncus in depressions and Brachythecium mildeanum, Aulacomnium palustre, Dicranum bonjeanii, Timmia megapolitana, Campylium stellatum and some others on elevated micro-sites); the vast majority of species are rare. A well-developed microrelief determines the diversity of micro-habitats, to ensure the coexistence of species of different ecology and origin. More than half of the recorded species are indifferent to mires and random. The most interesting findings (Anomodon viticulosus, Anomodontella longifolia, Brachythecium rutabulum, Conardia compacta, Fissidens adianthoides, Myurella julacea, Platydictya jungermannioides, Zygodon sibiricus) are discussed. In densely populated areas, forest swamps are islands of natural vegetation and ensure the survival of many species.

Chorology and phytosociological affinity of Greater Spearwort (Ranunculus lingua L.) in Slovakia

Ranunculus lingua is an Euro-Siberian vascular plant species of freshwater habitats. Distribution and vegetation preferences of this rare species, which is native to the Slovak flora, have not yet been critically revised. The present paper aimed i) to provide the first complex distribution pattern of this species in Slovakia and ii) to analyse all available vegetation plots with species occurrence in order to elucidate the variability of plant communities. The distribution data were retrieved from herbarium specimens, literature records and field surveys. Our revision suggests that R. lingua was found particularly in the lowland areas of the western, south-western and south-eastern parts of the country. It was very rare in other regions of Slovakia, and several populations have become extinct due to drainage or habitat destruction. New localities of secondary origin were additionally documented in some human-made habitats. The temporal trend showed a strong decrease in the number of localities in natural habitats, mainly in the hilly and mountainous regions of the Western Carpathians from the 1980s to the end of the twentieth century. R. lingua was recorded in both forest and treeless swamp communities. Vegetation analysis revealed numerous records mainly in eutrophic marshes (Phragmito-Magnocaricetea class), willow and alder carrs (Franguletea and Alnetea glutinosae).

Растительность осоково-гипновых и лесных болот богатого грунтового питания на северной границе их распространения в Западной Сибири

The vegetation of sedge-hypnum and forest swamps rich in soil nutrition was studied in “Chistoe Boloto” (Open Mire), located in the low left-bank terrace of the Irtysh River valley in the environs of Tobolsk city (58.25°–58.09°N, 68.15°–68.34°E) near the northern limit of this mire type distribution in Western Siberia. A total of 7 associations, 2 subassociations, 1 variant, and 1 community type are described, of which one association (Hamatocauli vernicosae–Caricetum lasiocarpae) and 2 subassociations (Telypterido palustris–Betuletum pubescentis inops and Thelypteridetum palustris brachythecietosum mildeanae) are introduced as new ones. Communities are assigned to 4 alliances of 3 orders and 2 classes. The class Alnetea glutinosae Br.-Bl. et Tx. ex Weshoff et al. 1946 of coniferous and small-leaved forests of Eurasia includes the order Calamagrostio purpureae–Piceetalia obovatae Lapshina 2010 combining forest-like swamp communities with dark coniferous species in the tree layer, called “sogra” in Siberia, with two associations within 2 alliances in the study area. Ass. Mnio stellari–Pinetum sibiricae Lapshina 2010 (Fig. 2) of the alliance Carici cespitosae–Piceion obovatae Lapshina 2010 includes communities of the dark coniferous sogra. Their considerable geographical remoteness from the main distribution area in the south of the forest zone of Western Siberia and noticeable differences in the species composition allowed to establish within it var. Viola epipsila. Ass. Carici appropinquatae–Pinetum sylvestris Lapshina 2010 (Fig. 3) of the alliance Carici appropinquatae–Laricion sibiricae Lapshina 2010 combines birch–pine herb-tussock sedge communities, rich in soil nutrition, dominated by Carex apropinquata, Thelypteris palustris. The class Scheuchzeria palustris–Caricetea nigrae Tx. 1937 is represented by the alliance Saxifrago-Tomentypnion Lapshina 2010 in the study area. Diverse communities of sedge-hypnum and Menyanthes-low sedge-hypnum fens, which are visually well distinguished in the vegetation cover by the dominance of different sedge species (Сarex diandra, C. dioica, C. limosa, C. rostrata) and Menyanthes, correspond well in their floristic composition to the diagnosis of the ass. Brachythecio mildeanae–Caricetum limosae Lapshina 2010 (Fig. 6) described on the hypnum fens in the southeast of Western Siberia. With the distance from the Tobolsk slope and gradual reduction of the groundwater influence, the domination in Menyanthes-low sedge-hypnum communities gradually flows from the ass. Brachythecio mildeanae–Caricetum limosae to Carex lasiocarpa — ass. Hamatocauli vernicosae–Caricetum lasiocarpae ass. Nov (Fig. 7). A characteristic feature of the studied mire is the wide distribution of sedge-fern and fern communities among low sedge-hypnum fens dominated by Carex lasiocarpa and Thelypteris palustris, which are assigned to associations Thelypterido–Caricetum lasiocarpae Lapshina 2010 (Fig. 8) and Thelypteridetum palustris Lapshina et al. 2018 (Fig. 9). The latter is established as subass. brachythecietosum mildeanae subass. nov. Comparison of the of mire habitats is made based on L. G. Ramenskiy ecological scales (Ramensky et al., 1956). Ecological indices (grades) of water supply and nutrient condition for each relevé are calculated. The ecological ordination of mire habitats (Fig. 10) shows values for mineral nutrition (Y-axis), and for water supply (wetness) (X-axis). According to the scale of mineral nutrition, the t communities exist in a narrow ecological range corresponding to mesotrophic conditions (6.5–9.0 grades). This is due to the fact that at high values of electrical conductivity and a medium close to neutral (EC=180–430; pH=6.5–7.5), peat soils rich in ground nutrition are poor in nitrogen and phosphorus (Wassen et al., 2005). According to the humidity scale, the studied vegetation may be divided into 3 groups: communities of hydromesophilic (77–88 degrees), subhydrophilic (89–94 degrees), and aerohydrophilic (95–103 degrees) habitats corresponding to the main classes of mire vegetation. The first group includes syntaxa of two alliances of wooded swamps of the class Alnetea glutinosae, which occur in moderately humid habitats. The low birch swamps communities of the class Alnetea glutinosae are common in higher water saturated habitats. Syntaxa of low sedge-hypnum, fern, and sedge-fern fens of the class Scheuchzerio–Caricetea nigrae are common to the most wet fen habitats, often associated with high level of water horizons buried in peat deposits. The classification results and ordination of syntaxa are confirmed by the t-SNE method, which allows displaying multidimensional hyperspaces on the plane. The right side of the ordination diagram (Fig. 11) shows well-differentiated low sedge-hypnum fens communities of the class Scheuchzerio–Caricetea. The rare sedge-hypnum communities with the Paludella squarrosa dominance are located somewhat apart, bonded to the exits of springs. The opposite part of the diagram shows well-differentiated communities of wooded swamps within the class Alnetea glutinosae. They are adjoined by communities of the ass. Thelypterido palustris–Betuletum pubescentis, within of the class Alnetea glutinosae. The most difficult challenging was to determine the position of Carex lasiocarpa-dominated fern, sedge-fern and sedge-hypnum communities within the higher units of classification. They occur in ecologically similar habitats as low sedge-hypnum communities of the alliance Saxifrago-Tomentypnion with well-represented diagnostic species in these. Due to that and the presence of hypnum moss layer, we assigned these communities to the alliance Saxifrago-Tomentypnion of the class Scheuchzeria-Caricetea.

Botanical Assessments of High-Quality Southern Shrub-Carr and Hardwood Swamp Wetlands in the Undeveloped Lowell Regional Greenspace, Kent County, Michigan

The 2019–2023 Masterplan for Kent County Parks includes the future development of acquired properties that have been designated as the Lowell Regional Greenspace (528 acres), occupying nearly the entirety of Section 22 of Lowell Charter Township in Kent County, Michigan. Four wetlands located in the same drainage basin along Karen Creek in the Lowell Regional Greenspace were inventoried for floristic quality assessments during the summers of 2016, 2018, 2019, and 2021. One of the wetlands was forested and determined to be a southern hardwood swamp community type. The other three wetlands are best classified as shrub-carr communities. In the southern hardwood swamp, we recorded 94 species, of which 87 (92%) are native. A total of 321 species were documented in the three shrub-carrs wetlands combined. The number of species in each shrub-carr site, ranging from 172 to 238, is roughly twice that for the southern hardwood swamp site. Two of the species documented are listed as Special Concern in Michigan, and two are new county records for Kent County, Michigan. A non-metric multidimensional scaling model (NMDS) was run to spatially compare similarities and differences among the sites. The Sørensen Index of Similarity, which was employed to further discern differences between pairs of individual sites, was also useful for assigning plant community types as described by the Michigan Natural Features Inventory (2016). The Floristic Quality Assessments indicate that all four of the wetlands are floristically important statewide; furthermore, the three shrub-carr communities have exceptional conservation value. We discovered that the three shrub-carr sites have a high degree of similarity in their species assemblages, whereas the southern hardwood swamp was markedly different. The high richness and significant floristic quality of the shrub-carr sites highlight the conservation value of these often-overlooked habitats. This study underscores the importance of preserving even small tracts of persisting remnant natural habitats. Our research should be of use to Kent County Parks as they approach development of the Lowell Regional Greenspace into a multiple-use recreational space, as well as to those interested in learning more about how to assess and compare habitat quality of remnant natural areas.

Karst Ecosystems of Middle Timan, Russia: Soils, Plant Communities, and Soil Oribatid Mites

Oribatid mites are distinguished by high taxonomic diversity and abundance in almost all natural zones; they are used as an indicator group of microarthropods in the study of natural landscapes and anthropogenically disturbed ecosystems. In the karst landscapes of the North, the oribatid mites are very poorly studied. The aim of this study was to investigate the diversity of soil types, plant communities, and oribatid mites in karst relief forms in the conditions of the northern taiga forests. The material was collected in July 2020 in the karst landscapes of Timan Ridge, found in the European northeast of Russia. The research sites were located in the profile of the karst crater and in the profile of the slope in the Ukhta River Valley. A sedge wetland community, and pine–bilberry–green-moss forest, located in the depression between glacial hills and uplands were also examined. A total of seven sites were examined. Geobotanical descriptions were made by standard methods, descriptions of the soil profile, and samples of the soil microfauna; 12 in each site were collected. A total of 51 oribatid mite species from 39 genera and 31 families were found. The highest taxonomic diversity of oribatids was noted in forest phytocenoses located in the upper part of the karst crater slope, the lower part of the karst crater slope, and on rock outcrops in the lower part of the slope in Ukhta river valley. Ordination of the oribatid mite community by NMDS method showed the association of sites S3, S4, and S5 located on the slope of the karst crater in one group, and sites S6 and S7 located on a slope in the Ukhta River Valley, as well as S2 (pine–bilberry–green-moss forest located in the depression between glacial hills and uplands), in another group. The swamp community was located separately from other communities. Species of oribatid mites, which created the specifics of each community, were noted. The specifics of the population of oribatid mites of karst landscapes were that along with the features of fauna, characteristic for zonal north-taiga forests (the predominance of polyzonal widespread species) were found the “conditionally southern” species, the main area of distribution of which is located in lower latitudes. The study provides the basis for future studies of poorly known oribatid mites of karst landscapes of Northern Europe.

Birch-sedge communities, forest withdrawal and flooding at the beginning of Heinrich Stadial 3 at the southern Alpine foreland

The southern Alpine foreland, facing windward to moist southern airmasses, is claimed to have supported forest vegetation throughout the Last Glaciation. Here we present a multiproxy paleoecological record from a compressed peat, uncovered at Casaletto Ceredano, N-Italy, spanning the interval from 33 to 30.5 kyr cal BP. Stratigraphically, it underlies a fluvioglacial belt attributed to the Last Glacial Maximum. The peat records a floodplain swamp community with tree birch and tall sedges, pine woodlands in upland areas, and only limited patches of open vegetation. Plant macrofossils – bark, charcoal, wood and fruits – establish the predominant role of Betula pubescens group (downy birch) in the anoxic wetland, thanks to its ability to enhance gas exchange through a distinctive type of bark lenticels. A fire-induced birch-to-pine cycle is repeated twice along the 2500 years-time span covered by the peat layer. The climate reconstructed from modern pollen analogs compares to northern boreal zone, with Tjuly <15 °C, excluding warm-temperate trees.A major flood sealing the swamp with minerogenic silt is precisely dated to 30,497 ± 594 yr cal BP (2σ uncertainty). Here, the pollen record shows a substantial forest withdrawal, and development of grasslands and semideserts, pointing to co-factorial action of increased climate continentality and of river dynamics. According to teleconnections with the Atlantic and Arctic framework of the stadial–interstadial climate variability, the age and pattern of this event are consistent with the onset of Heinrich Stadial 3, causing a lockdown of moist westerlies and of their Rossby waves in the W-Mediterranean.

Sero-prevalence of arthropod-borne viral infections among Lukanga swamp residents in Zambia.

IntroductionThe re-emergence of vector borne diseases affecting millions of people in recent years has drawn attention to arboviruses globally. Here, we report on the sero-prevalence of chikungunya virus (CHIKV), dengue virus (DENV), mayaro virus (MAYV) and zika virus (ZIKV) in a swamp community in Zambia.MethodsWe collected blood and saliva samples from residents of Lukanga swamps in 2016 during a mass-cholera vaccination campaign. Over 10,000 residents were vaccinated with two doses of Shanchol™ during this period. The biological samples were collected prior to vaccination (baseline) and at specified time points after vaccination. We tested a total of 214 baseline stored serum samples for IgG antibodies against NS1 of DENV and ZIKV and E2 of CHIKV and MAYV on ELISA. We defined sero-prevalence as the proportion of participants with optical density (OD) values above a defined cut-off value, determined using a finite mixture model.ResultsOf the 214 participants, 79 (36.9%; 95% CI 30.5–43.8) were sero-positive for Chikungunya; 23 (10.8%; 95% CI 6.9–15.7) for Zika, 36 (16.8%; 95% CI 12.1–22.5) for Dengue and 42 (19.6%; 95% CI 14.5–25.6) for Mayaro. Older participants were more likely to have Zika virus whilst those involved with fishing activities were at greater risk of contracting Chikungunya virus. Among all the antigens tested, we also found that Chikungunya saliva antibody titres correlated with baseline serum titres (Spearman’s correlation coefficient = 0.222; p = 0.03).ConclusionArbovirus transmission is occurring in Zambia. This requires proper screening tools as well as surveillance data to accurately report on disease burden in Zambia.

Среднеюрские растения-углеобразователи Улуг-Хемского бассейна (Республика Тыва, Россия)

Dispersed cuticles of plants from coals of the Middle Jurassic Ulugkhem Formation (locality 229 near Mount Begreda, Ulug-Khem Basin, Republic of Tyva) were studied. As a result of the study of mesofossils using light and scanning electron microscopes, it was found that the coals are composed mainly of the remains of ginkgophytes. They are represented by the leaves of Pseudotorellia cf. angustifolia Doludenko, the female reproductive organs of this plant Umaltolepis sp., as well as the leaves of Eretmophyllum neimengguensis Li, Sun, Wang, Dilcher, Tan, Li, Na. The conifers played subordinate role. The palynospectrum of the coal seam is dominated by the spores of ferns; bisaccate and monosulcate pollen are next in importance. Thus, ginkgophytes and ferns predominated in the Middle Jurassic swamp communities in the Ulugh-Khem Basin. For the first time, the coal-forming role of the genus Eretmophyllum was revealed. The Middle Jurassic flora of Tyva is similar to the floras of the Kansk-Achinsk and Irkutsk basins of Eastern Siberia, Angren Basin of Uzbekistan, and the Ordos Basin of Inner Mongolia, China by predominance of Pseudotorellia. The vegetation was clearly differentiated into the lowland and the slope one. In the latter the leptostrobaleans, ginkgoaleans, and conifers were represented. Pseudotorellia is one of the main components of swamp plant communities in the more northern regions: in the Ulug-Khem and Irkutsk basins, and in the Aban and Pereyaslovka coal fields of the Kansk-Achinsk Basin. This genus disappears in the Nazarovo coal field of the Kansk-Achinsk Basin, being replaced by the leptostrobaleans. Here the compositions of swamp and slope communities practically do not differ. The Late Mesozoic swamp plant communities were characterized by conservatism, as well as by extreme sensitivity to environmental changes, which apparently developed because of their existence in the same conditions of high humidity. Degradation of the swamps led to the disappearance of swamp plant communities.

Evidence for trait‐based community assembly patterns in hardwood hammock forests

AbstractThe hardwood forests of south Florida, commonly referred to as hammocks, persist as well‐drained patches of broadleaf forest, embedded in a matrix of brackish water swamp, freshwater marsh, or pineland. Little is known about the patterns of community assembly of these subtropical forest communities in the landscape mosaic of south Florida. We used a functional trait approach to understand the composition of these communities and their responses to environmental variation across four areas of south Florida: the pine rocklands and freshwater marshes in Everglades National Park, and the lower and upper Florida Keys, where the hammocks are surrounded by halophytic swamp communities. These sites represent an environmental gradient from less‐productive, more xeric sites in the lower Florida Keys, to more‐productive, wetter sites in the Everglades marshes. We examined the patterns of trait variation at three levels (individual, population, and community) to examine the underlying processes driving assembly in these hammock communities. To understand processes governing community composition in each site, we used methods that partition variance in six traits (maximum tree height, specific leaf area, wood specific gravity, leaf nitrogen, leaf phosphorus, and leaf stable carbon isotope ratios) into internal and external filtering components. Community‐weighted mean trait values for three traits (specific leaf area, height, and leaf phosphorus) increased significantly from dry, less‐productive coastal sites in the Florida Keys to the moist, more‐productive areas on the mainland, while wood specific gravity and leaf δ13C showed the opposite pattern. For one or more traits per site, standardized effect sizes differed significantly from null expectation. Processes such as competition for resources (e.g., water, nutrients, light) and species sorting across microhabitats (i.e., within site) operate to increase local functional trait variation within communities and among species across sites. External filtering on individuals for height and leaf phosphorus differed significantly from null expectations across sites, while external filtering on species was only observed for specific leaf area, maximum tree height, and leaf phosphorus. These results are consistent with strong environmental filtering across the region, among local communities differing in freshwater accessibility or that occupy different positions along strong edaphic gradients. Our results confirm the importance of intraspecific variation among species and reflect a high degree of trait plasticity across the environmental gradient.

Drained ash swamp (Veratro albi-Fraxinetum angustifoliae), a new association in the Nyírség, NE Hungary

This paper presents the phytosociological description of a drained swamp community, Veratro albi-Fraxinetum angustifoliae, so far found only in the Nyírség at Nyírábrány “Kis-kőrises”, “Mogyorósi-erdő”; Vámospércs “Jónásrész-Kőrises”; and Vámospércs “Jónásrész-Buzita”. The habitat of the community is transitional between that of alder swamps (Fraxino pannonicae-Alnetum glutinosae), and hardwood riparian forests (Fraxino pannonicae-Ulmetum). The community is characterised by high proportions of character species of Alnion glutinosae and Molinion coerulei as well as Quercetea pubescentis-petraeae s. l. whereas character species of the order Fagetalia are almost completely absent. It hosts several rare, often threatened species, such as Angelica palustris, Ophioglossum vulgatum, Trollius europaeus and Veratrum album.

Palynological Study of OSE 1 Well in Offshore Niger Delta Basin: Implications for Age, Paleoclimate and Depositional Paleoenvironment

Palynological study of 45 ditch samples from sedimentary successions penetrated by OSE 1 well located offshore western Niger Delta Basin was undertaken to determine the age of the sediment and reconstruct the paleoclimate and depositional paleoenvironment. All the analyzed samples were composited at 30 ft from stratigraphic depth interval of 6330 to 9010 ft. The lithologic composition comprised mainly of brownish grey or light grey, fine-grained shales with a gypsiferous horizon near the bottom. Palynological slides were prepared following standard palynological preparation procedures of sample maceration with hydrochloric (HCl) and hydrofluoric (HF) acids. The samples yielded moderately well-preserved, low to high diversity palynomorph assemblages of 58 taxa comprising 29 pollen grains, 9 pteridophic spores, 17 dinoflagellates, one acritarch, one freshwater algae and a fungi spore. The stratigraphic distribution of microflora assemblages was highly variable. The assemblage abundance was dominated by pollen and spores. The retrieved pollen grains included Monoporites annulatus, Sapotaceoidaepollenites sp. Psilatricolporites crassus, Psilatricolporites sp., Zonocostites ramonae, Retitricolporites irregularis, Monocolpites marginatus, Monocolpites sp., Pachydermites diederixi, Proxapertites cursus, Verrutricolporites rotundiporus, Striatopollis catatumbus, Retistephanocolpites gracilis, Echiperiporites estalae, Echiperiporites sp. and Inaperturopollenites sp. The retrieved spores included Magnastriatites howardi, Acrostichum aureum, Laevigatosporites sp., Polypodiaceoisporites sp., Verrucatosporites sp., Crassoretitriletes vanraadshooveni and Stereisporites sp. The recorded dinoflagellates included Achomosphaera sp., Andalusiella sp., Polysphaeridium zoharyi, Selenopemphix nephroides and Spiniferites sp. Leiosphaeridia sp. was the only acritarch present in the assemblage. The freshwater algae was Botryococcus braunii. Fungi spore was present but not in significant amount. The stratigraphic interval was dated Early to Late Miocene (Burgidalian-Messinian) based on the occurrence and distribution of some stratigraphic fossil marker species including Magnatriatites howardi, Crassoretitriletes vanraadshooveni and Retistephanocolpites gracilis The abundant occurrence of pollen and spores typical of rain forest and freshwater swamp communities in the assemblage indicated tropical paleoclimatic conditions. The distribution pattern of Monoporites annulatus (Poaceae) and Zonocostites ramonae (Rhizophora) suggested seasonal fluctuations between dryer and wetter climatic conditions. The sediments were deposited in a wide range of environments including brackish lagoons, open salt water swamps, freahwater and nearshore to inner neritic settings.

The disturbance regime of an Early Holocene swamp forest in the Czech Republic, as revealed by dendroecological, pollen and macrofossil data

A unique remnant of forest dating back to the period 9733–7897 yr BC and consisting of hundreds of tree bases was discovered in the Czech Republic. We aimed to reveal the complex disturbance history of this (sub)fossil forest using dendrochronology, and to describe its detailed plant species composition changes using palaeobotanical techniques. Analysing such Early Holocene forest dynamics should help us understand the ability of the forest community to actively adapt to climate change and generally to understand the role of dynamic instability in ecosystem evolution.We anatomically identified woody species in 488 samples, and determined the ages, growth suppressions, releases and fire scars in 116 well preserved tree ring series using a modern boundary line approach. This image of the forest structure and dynamics was supplemented with analyses of pollen spectra and plant macrofossils in excavated profiles. In order to achieve accurate dating, we dated 87 samples using 14C and synchronized tree ring series, and compared them with an existing Pinus sylvestris chronology.The developmental trajectory of the forest was unique, and did not match the general trend of postglacial pine growth in central Europe. Palaeobotanical proxies indicated that during the circa 2000 years the forest persisted, this Early-Holocene ecosystem passed through several phases, reflected in the species composition of the vegetation as well as in habitat conditions. Nevertheless, the dominance of pine and the complex fine-scale disturbance regime were relatively robust and did not change fundamentally. Low-severity fires and short-term changes in soil moisture regime were crucial disturbance agents in the ecosystem. Stand-replacing disturbances were not found up to the gradual collapse of the forest around 8300 yr BC, replaced by a swamp community. The disturbance regime was relatively stable, suggesting a mitigating effect of changing climate due to the predominance of pine in the forest.

The Rare Southern Twayblade (Neottia bifolia): Sentinel of Ecosystem Integrity For Sphagnous Swamps

Long-term monitoring of the rare southern twayblade (Neottia bifolia; Orchidaceae) and understorey of a black spruce-tamarack, swamp community was conducted after construction of an airport taxiway above the swamp edge. Succession documented over 14 years in the treed swamp edge following disturbance involved loss of the twayblade, invasion by guilds of annuals, and shifts between original and new guilds of wetland plants. Despite changes, the twayblade was the only plant extirpated from the swamp edge community although fungal richness (mainly basidiomycete) was substantially lower in the edge than the swamp interior. NMS ordination indicated that the orchid niche is an undisturbed swamp with an intact tree canopy and unbroken mat of Sphagnum which supports a diverse mycorrhizal community adapted to summer water table drawdown and low ionic groundwater chemistry (e.g. Cl<10 mg/L). Fourteen years after the disturbance, southern twayblade populations in the swamp interior, 100 m from the edge were in steady decline. The woodland orchids may be sentinels of ecosystem integrity. Loss of the twayblade signalled the onset of a post-development, disturbance-cascade: installation of an impervious surface restricted infiltration, altered run-off quantity and quality which subsequently resulted in loss of the ecosystem engineer, Sphagnum, and keystone mycorrhizal fungi.

Aquatic Ecosystem Degradation of High Conservation Value Upland Swamps, Blue Mountains Australia

Temperate highland peat swamps on sandstone (THPSS) are unique state and federally protected ecological communities. THPSS is a higher level classification which is comprised of multiple swamp communities which include Blue Mountains Swamps and Newnes Plateau Shrub Swamps. The Blue Mountains has a string of urban settlements surrounded by large expanses of undisturbed natural vegetation which have varied degrees of protection ranging from state forests to World Heritage national parks. This study investigated aquatic invertebrates from seven THPSS within the Greater Blue Mountains area. Four swamps drain catchments with varying degrees of urban development and associated impervious surfaces, and three swamps have non-urban, naturally vegetated catchments. Water chemistry of non-urban swamps was acidic (mean pH 4.70) and dilute (mean EC 26.7 uS/cm) and dominated by sodium and chloride ions with most other major ions at low concentrations often below detection limits (Belmer et al. 2015). In contrast, urban swamps had higher pH (mean 6.60) and salinity (mean 153.9 uS/cm) and were dominated by calcium and bicarbonate ions (Belmer et al. 2015). Aquatic macroinvertebrate abundance, family richness and % EPT taxa were all found to be lower within urban swamps when compared to non-urban swamps. These results support the hypothesis of Belmer et al. (2015) that urban runoff within THPSS catchments is affecting the condition of their aquatic ecosystems.

Mechanisms Involved in Soil Ammonium Production in a Mauritia flexuosa Palm Swamp Community

When soils are water saturated, the reduced forms of soil nitrogen such as ammonium are favored. Under anaerobiosis, ammonium production has been explained by several mechanisms such as organic nitrogen mineralization (ONM), dissimilatory nitrate reduction to ammonium (DNRA) and the release of adsorbed ammonium during microbial reduction of iron oxides (MRFeO). Nevertheless, in anaerobic soils the dominance of one mechanism over the others is still debated. Nitrogen appears to influence the reproductive dynamics of Mauritia flexuosa, the dominant canopy species of the “morichal” ecosystem. Even though M. flexuosa has been classified as “vulnerable”, ammonium production in morichal soils is not well understood. Considering this, we evaluated in a morichal soil from SE Venezuela, the mechanisms associated with ammonium production under anaerobic conditions. To this end, we designed an anaerobic incubation experiment to follow over time the concentrations of nitrate, extractable ferrous iron and ammonium together with the activity of β-glucosaminidase as an index of N mineralization. To account for the relative importance of ONM, DNRA and MRFeO on ammonium production, we used multiple linear regression models. The results showed that the three mechanisms are involved in ammonium production. However, ONM is the main source of ammonium in the initial 15 days of soil incubation, while MRFeO explains ammonium produced after 15 days of soil incubation. However, under climate change scenarios these mechanisms may be altered, thereby increasing the N limitation of morichales and consequently its vulnerability. Since morichales are threatened ecosystems, that play a key ecological, economic and cultural role, studies on the soil nitrogen dynamics are important to design and evaluate effective management, conservation and protection strategies. This study can be a relevant contribution in this area.

Miocene palynoflora from the KRAM-P 218 leaf assemblage from the Bełchatów Lignite Mine (Central Poland)

Abstract During a palynological analysis of four samples from the Bełchatów KRAM-P 218 collection of plant macroremains 95 fossil species of sporomorphs were identified. Among the non-pollen palynomorphs was the fossil species Desmidiaceaesporites cosmarioformis, previously not reported from fossil floras of Poland, most probably related to the zygospores of desmids. The pollen analysis indicates the presence of a freshwater body (probably an oxbow lake) and shows the dominant role of wetland, predominantly riparian vegetation, at the time of sedimentation. The riparian forests probably consisted of Carya, Pterocarya, Celtis, and Ulmus, accompanied by Alnus, Acer, Fraxinus, Juglans, Liquidambar, Vitis, Zelkova, and Salix. In mixed forests there probably were Fagus, Quercus, Carpinus, Eucommia, Corylus, Tilioideae, and conifers, as well as some thermophilous taxa (e.g. Castanea, Symplocos, Reevesia, Mastixiaceae, and plants producing pollen of the fossil species Tricolporopollenites pseudocingulum). Taxodium, Nyssa, and presumably Glyptostrobus and Alnus were components of swamp communities that might have overgrown the adjacent area with higher groundwater. Members of the families Ericaceae, Cyrillaceae, and Clethraceae, as well as Myrica and probably also Ilex, may have been components of swamp forests and bush swamps. Our analysis indicates that the climate was warm temperate and moderately wet. The palynoflora is most similar in composition to the spore-pollen spectra of the X climatic phase - the Nyssapollenites spore-pollen zone. Deposits bearing assemblages of the Nyssapollenites spore-pollen zone were deposited during the Sarmatian and early Pannonian. Our results are consistent with those from plant macroremains from the same collection.

Vegetation change and conservation status of Coastal Upland Swamps

SummaryCoastal Upland Swamp communities are characterized by high biodiversity and provide habitat for a range of threatened flora and fauna. In this research project, we are monitoring swamp vegetation dynamics over decadal timescales and relating observed changes to environmental factors. We have also modelled potential effects of climate change on swamp distributions. We found that swamp communities are spatially dynamic, both internally and in relation to the woodland matrix. Transitions between communities depended on initial states. In addition, these water‐dependent communities appeared highly sensitive to projected climate change and their ‘Endangered’ status makes their active management a high priority. Improved understanding of dynamics at the community and landscape scale facilitates horizon scanning and improves our capacity to plan effective management interventions now and under future management and climate change scenarios.

INFLUENCE OF GRAZING INTENSITY ON SWAMP PLANT COMMUNITIES IN THE TROPICAL MONTANE WETLAND ECOSYSTEMS, NILGIRIS, SOUTHERN INDIA

Livestock grazing is a major anthropogenic impact influencing both grasslands and wetlands of the world which often results in the alteration of the structure, diversity and functioning of the plant communities. Here, we seek to understand how grazing intensity influences swamp vegetation, with an emphasis on their diversity, structure and function. Six swamps were selected, two each in high, moderate and low intensity grazing sites, from the tropical montane swamps of the Upper Nilgiri Mountains, southern India. We recorded a total of 78 species belonging to 63 genera and 31 families. Our results showed that species richness, abundance and species composition differed significantly across grazing treatments. Moreover, mean vegetation cover and mean height differed significantly across grazing treatments, indicating that grazing significantly affected the vegetation structure and growth of swamp plant communities. Species compositional patterns showed that moderately grazed plant communities were significantly different from low and high grazing sites. In summary, grazing intensity influenced swamp species richness, abundance, and swamp plant communities. Specifically, high grazing pressure reduced vegetation cover causing changes in swamp community structure leading to the gradual conversion of the swamp habitat into grasslands.

Dynamics of production and accumulation of phytolith assemblages in the Restinga of Maricá, Rio De Janeiro, Brazil

Abstract The Marica “restinga”, located on the eastern part of Rio de Janeiro State (Brazil), corresponds to one of the few remaining preserved areas of the state's coastal plain. This coastline presents two sand barriers separated by a depression where there is a freshwater swamp and different plant communities distributed in areas of high ecological diversity accompanying the local topography and the range of marine spray. This paper is a study of the soil phytolith assemblages in the Marica restinga, with the intent of establishing reference collections for paleoenvironmental studies of this coastal area during the Quaternary. Phytoliths were chosen as proxies, but their use for reconstruction of this type of vegetation is pioneer research, so it was essential to characterize the phytolith assemblages for each plant community through the identification of the main morphotypes and whether or not they are preserved in coastal depositional environments under the effect of geomorphology and salinity. Eight plant communities, distributed almost parallel to the coastline over sandy barriers, lagoonal plain, lagoon margin and weathered basement were identified: Halophile-psamophile, near the beach; two Scrub communities, one over the Holocene barrier and the other over the Pleistocene barrier; two Herbaceous swamps, one between the two sand barriers, the other behind the Pleistocene barrier; Slack, in front of the Pleistocene barrier; Shrubby vegetation on the shore of Marica lagoon and Dry forest, over the weathered Pre-Cambrian basement. In general, it was found that this type of environment is not very favorable for the formation and accumulation of phytoliths. Restinga plants did not prove to be large producers of phytoliths, except those known as such, as in the case of Poaceae and Cyperaceae. It was also observed that the permanence of phytoliths in sediments is strongly influenced by its particle size and organic matter content. The largest stocks of phytoliths were found in swamp communities, due to the presence of organic matter and low energy dynamics, and in dry forests, where a process of pedogenesis already occurs. Despite the low phytolith stocks present in modern assemblages, they show a high degree of conservation, which enabled significant results for the study of this type of vegetation. The calculated phytolith indices (tree density and water stress) consistently expressed, in detail, the environment of each community analyzed from the point of view of the type of vegetation cover and the conditions of water availability to plants.