У пошуках українського образу Одеси

У даній статті розглядається проблема українського образу Одеси на прикладі поезії Ю. Шевченка. Ключові слова: український образ міста, образ українського міста, поетичний образ міста, міський текст, тести про місто.В данной статье рассматривается проблема украинского образа Одессы на примере поэзии Ю. Шевченко. Ключевые слова: украинский образ города, образ украинского города, поэтический образ города, городской текст, тексты о городе.The problem of definition of the Ukrainian image of Odessa on an example of Y. Shevchenko’s poetry is considered in this article. Keywords: the Ukrainian image of city, an image of the Ukrainian city, a poetic image of city, the city text, texts about city

Werken de KRW- en Natura 2000-criteria voor sloten en veenplassen?

Toepassing van de Kaderrichtlijn Water en de normen conform Natura 2000 vragen om een evaluatie van de effectiviteit. De KRW blijkt een correct middel om maatregelen te nemen, maar in de hoogste klasse is het onderscheid (te) gering. Worden de doelen van de Natura 2000-habitats 'evenwichtige laagveensystemen met daarmee verbonden laagveenverlanding' ook gehaald? Onderzoek van waterplanten in twee Natura 2000-habitats, namelijk laagveenplassen en -sloten, toont duidelijk aan dat essentiele schakels in de systemen niet meer voldoende aanwezig zijn. De waarnemingen bestaan vrijwel geheel uit losse individuele planten, indien al aanwezig. Losse krabbenscheerplanten in een zee grof hoornblad vormen geen eindstadium van verlanding in veenplassen zoals de criteria voor Natura 2000 aangeve

Using the Tea Bag Index to unravel how interactions between an antibiotic (Trimethoprim) and endocrine disruptor (17a-estradiol) affect aquatic microbial activity: Supporting Dataset 1

The constant release of complex mixture of pharmaceuticals, including antimicrobials and endocrine disruptors, into the aquatic environment. These have the potential to affect aquatic microbial metabolism and alter biogeochemical cycling of carbon and nutrients. We used the Tea Bag Index (TBI) for decomposition within a series of contaminant exposure experiments to test how interactions between an antibiotic (trimethoprim) and endocrine disruptor (17a-estradiol) affects microbial activity in an aquatic system. The TBI is a citizen science tool used to test microbial activity by measuring the differential degradation of green and rooibos tea as proxies for labile and recalcitrant organic matter decomposition. Here we present the raw data on pharmaceutical exposures and the mass loss of the Rooibos and Green tea bags within the experiment. From Tea Bag mass loss we then calculated the Stabilisation Factor (S) and Initial Decomposition Rate of the labile organic matter fraction

Reasons to not correct for leaching in TBI; Reply to Lind et al. (2022)

We believe that correcting for leaching in (terrestrial) litterbags studies such as the Tea Bag Index will result in more uncertainties than it resolves. This is mainly because leaching occurs in pulses upon changes in the environment and because leached material can still be mineralized after leaching. Furthermore, amount of material that potentially leaches from tea is comparable to other litter types. When correcting for leaching, it is key to be specific about the employed method, just like being specific about the study specific definition of decomposition

Turbary restoration meets variable success: does landscape structure force colonization success of wetland plants?

Peat ponds have been restored widely in the Netherlands to enhance the available habitat for species-rich plant communities that characterize the early succession stages toward land. Colonization success of 33 target aquatic species has been quantified in eight complexes of new ponds. It has been related to the lay-out of these ponds, the structure of the surrounding landscape, (historic) prevalence of source populations within the complex and within a perimeter of 10 km, and pond water quality. Colonization success was variable: between 6 and 26 target species had reached the complexes in 1998. This success was coupled to the first principal component (PC) in a principal component analysis (PCA) explaining 44% of the variation in 27 variables. This first PC correlated with historical perimeter and local within-complex species richness, the number of ponds in the complex, the SW orientation of ditches in these complexes and pH, and transparency of the water. Age of the ponds (1-9 years), area of open water (8-42%), and shoreline density (13-43 km/k

Species traits interact with stress level to determine intraspecific facilitation and competition

Questions Flooding and drought stress are expected to increase significantly across the world and plant responses to these abiotic changes may be mediated by plant–plant interactions. Stress tolerance and recovery often require a biomass investment that may have consequences for these plant–plant interactions. Therefore, we questioned whether phenotypic plasticity in response to flooding and drought affected the balance between competition and facilitation for species with specific adaptations to drought or flooding. Location Utrecht University. Methods Stem elongation, root porosity, root:shoot ratio and biomass production were measured for six species during drought, well-drained and submerged conditions when grown alone or together with conspecifics. We quantified competition and facilitation as the ‘neighbour intensity effect’ directly after the 10-day treatment and again after a seven-day recovery period in well-drained conditions. Results Water stress, planting density and species identity interactively affected standardized stem elongation in a way that could lead to facilitation during submergence for species that preferably grow in wet soils. Root porosity was affected by the interaction between neighbour presence and time-step. Plant traits were only slightly affected during drought. The calculated neighbour interaction effect indicated facilitation for wetland species during submerged conditions and, after a period to recover from flooding, for species that prefer dry habitats. Conclusions Our results imply that changing plant–plant interactions in response to submergence and to a lesser extent to drought should be considered when predicting vegetation dynamics due to changing hydroclimatic regimes. Moreover, facilitation during a recovery period may enable species maladapted to flooding to persist

Overcoming establishment thresholds for peat mosses in human-made bog pools

Globally, peatlands have been affected by drainage and peat extraction, with adverse effects on their functioning and services. To restore peat‐forming vegetation, drained bogs are being rewetted on a large scale. Although this practice results in higher groundwater levels, unfortunately it often creates deep lakes in parts where peat was extracted to greater depths than the surroundings. Revegetation of these deeper waters by peat mosses appears to be challenging due to strong abiotic feedbacks that keep these systems in an undesired bare state. In this study, we theoretically explore if a floating peat mat and an open human‐made bog lake can be considered two alternative stable states using a simple model, and experimentally test in the field whether stable states are present, and whether a state shift can be accomplished using floating biodegradable structures that mimic buoyant peat. We transplanted two peat moss species into these structures (pioneer sp. Sphagnum cuspidatum and later‐successional sp. S. palustre) with and without additional organic substrate. Our model suggests that these open human‐made bog lakes and floating peat mats can indeed be regarded as alternative stable states. Natural recovery by spontaneous peat moss growth, i.e., a state shift from open water to floating mats, is only possible when the water table is sufficiently shallow to avoid light limitation (<0.29 m at our site). Our experiment revealed that alternative stable states are present and that the floating structures facilitated the growth of pioneer S. cuspidatum and vascular plants. Organic substrate addition particularly facilitated vascular plant growth, which correlated to higher moss height. The structures remained too wet for the late‐successional species S. palustre. We conclude that open water and floating peat mats in human‐made bog lakes can be considered two alternative stable states, and that temporary floating establishment structures can induce a state shift from the open water state to peat‐forming vegetation state. These findings imply that for successful restoration, there is a clear water depth threshold to enable peat moss growth and there is no need for addition of large amounts of donor‐peat substrate. Correct species selection for restoration is crucial for success

Onderzoek ten behoeve van het herstel en beheer van Nederlandse laagveenwateren; eindrapportage 2003-2006

Dit rapport presenteert de resultaten en conclusies van het onderzoek aan laagveenwateren binnen het kader van het Overlevingsplan Bos en Natuur in de eerste fase (obn, 2003-2006). In Hoofdstuk 3 wordt een overzicht gegeven van de onderzoekslocaties. Vervolgens worden in Hoofdstuk 4 de belangrijkste bevindingen van het correlatieve onderzoek naar de samenhang tusen biodiversiteit en milieukwaliteit gepresenteerd, met in Hoofdstuk 5 de rol van hydrologie in het laagveenlandschap. In de daaropvolgende hoofdstukken 6 tot en met 10 staan de onderzoeksvragen, methoden, resultaten en conclusies van de verschillende deelonderzoeken weergegeven met betrekking tot visstandsbeheer (Hoofdstuk 6), water- en veenkwaliteit (Hoofdstuk 7), verlanding en veenvorming (Hoofdstuk 8), voedselwebrelaties (Hoofdstuk 9) en fauna (Hoofdstuk 10). Ten slotte worden in Hoofdstuk 11 de belangrijkste conclusies van het onderzoek in de eerste fase samengebracht en bediscussieerd, in relatie tot de directe betekenis voor het laagveenbeheer. Dit zal uitgewerkt worden aan de hand van de nieuw gegenereerde kennis en bestaande literatuur over de betreffende milieuproblemen (‘ver’-thema’s), en de voor- en nadelen van beschikbare OBN-maatregelen. Als afsluiting wordt aan de hand van de resultaten in fase 1 aangegeven welke onderzoeksvragen geprioriteerd zijn voor de tweede fas

Herbivore regulation of plant abundance in aquatic ecosystems.

Herbivory is a fundamental process that controls primary producer abundance and regulates energy and nutrient flows to higher trophic levels. Despite the recent proliferation of small-scale studies on herbivore effects on aquatic plants, there remains limited understanding of the factors that control consumer regulation of vascular plants in aquatic ecosystems. Our current knowledge of the regulation of primary producers has hindered efforts to understand the structure and functioning of aquatic ecosystems, and to manage such ecosystems effectively. We conducted a global meta-analysis of the outcomes of plant-herbivore interactions using a data set comprised of 326 values from 163 studies, in order to test two mechanistic hypotheses: first, that greater negative changes in plant abundance would be associated with higher herbivore biomass densities; second, that the magnitude of changes in plant abundance would vary with herbivore taxonomic identity. We found evidence that plant abundance declined with increased herbivore density, with plants eliminated at high densities. Significant between-taxa differences in impact were detected, with insects associated with smaller reductions in plant abundance than all other taxa. Similarly, birds caused smaller reductions in plant abundance than echinoderms, fish, or molluscs. Furthermore, larger reductions in plant abundance were detected for fish relative to crustaceans. We found a positive relationship between herbivore species richness and change in plant abundance, with the strongest reductions in plant abundance reported for low herbivore species richness, suggesting that greater herbivore diversity may protect against large reductions in plant abundance. Finally, we found that herbivore-plant nativeness was a key factor affecting the magnitude of herbivore impacts on plant abundance across a wide range of species assemblages. Assemblages comprised of invasive herbivores and native plant assemblages were associated with greater reductions in plant abundance compared with invasive herbivores and invasive plants, native herbivores and invasive plants, native herbivores and mixed-nativeness plants, and native herbivores and native plants. By contrast, assemblages comprised of native herbivores and invasive plants were associated with lower reductions in plant abundance compared with both mixed-nativeness herbivores and native plants, and native herbivores and native plants. However, the effects of herbivore-plant nativeness on changes in plant abundance were reduced at high herbivore densities. Our mean reductions in aquatic plant abundance are greater than those reported in the literature for terrestrial plants, but lower than aquatic algae. Our findings highlight the need for a substantial shift in how biologists incorporate plant-herbivore interactions into theories of aquatic ecosystem structure and functioning. Currently, the failure to incorporate top-down effects continues to hinder our capacity to understand and manage the ecological dynamics of habitats that contain aquatic plants