The Cryptogenic Red Alga <i>Bangia Atropurpurea</i> in Lough Derg, River Shannon, Ireland

The filamentous and euryhaline red alga Bangia atropurpurea (Rhodophyta, Bangiophyceae) is a little-known member of the Irish aquatic flora. Although a common freshwater species in the northern hemisphere, it seems that the lower Shannon Navigation is one of the principal freshwater localities for the species in Ireland. It was recorded from thirteen sites in Lough Derg in 1972 and in the 2010 survey reported here at 40 sites including islands and navigation buoys as well as on lock gates. It attaches to rocks and other hard surfaces immediately above and below the waterline. It may have been introduced to Lough Derg on the hulls of commercial vessels. Changes in climatic conditions, eutrophication, competition from other filamentous algae and fluctuating lake levels are all pressures that could affect the sustainability of Bangia within the Shannon Navigation. Nevertheless, this study shows that B. atropurpurea has persisted for at least 40 years in Lough Derg and remains widespread despite highly variable environmental conditions.

High growth rates and temporal or spatial opportunism are considered central to the success of filamentous algae, in particular for escaping or minimising the effects of herbivory. However, the role of chemical defences in filamentous algae has received far less attention. We investigated possible chemical feeding deterrence by filamentous red algae that have conspicuous cellular inclusions (Asparagopsis armata, Anotrichium tenue and Balliella amphiglanda) and 2 others without inclusions (Callithamnion korfense and Ulva sp.). The 3 algae with cellular inclusions were consumed at lower rates by a generalist amphipod, Hyale nigra, than the other 2 algae. To determine the potential role of chemical defences for A. armata, we conducted tests against herbivores using algae in which the production of halogenated metabolites was manipulated. This manipulation had no effect on carbon and nitrogen values of the algae, and allowed us to directly test the role of algal secondary metabolites in defence against herbivores without using artificial diets. Bromide (+) algae (with halogenated metabolites) deterred grazing by 2 mesograzers (Hyale nigra and juvenile abalone Haliotis rubra), which consumed up to 4 times more bromide (–) (metabolite-free) algae than bromide (+) algae. Juveniles of the sea hare Aplysia parvula were not deterred by the chemical defences in bromide (+) A. armata. In field assays, artificial diets containing a crude extract of A. armata were also active against herbivores. Although functional form models typically predict that tolerance—not resistance—should be the key defensive strategy for marine algae with simple architecture, this study demonstrates that resistance traits may also be important and more broadly utilised in filamentous species.

SummaryNatural systems are exposed to compounded perturbations, whose changes in temporal variance can be as important as those in mean intensity for shaping the structure of assemblages. Specifically, climate‐related physical disturbances and nutrient inputs due to natural and/or anthropogenic activities occur concomitantly, but experimental tests of the simultaneous effects of changes in the regime of more than one perturbation are generally lacking. Filling this gap is the key to understand ecological responses of natural assemblages to climate‐related change in the intensity and temporal patterning of physical disturbance combined with other global stressors.Responses to factorial manipulations of nutrient enrichment, mean intensity and temporal variability in storm‐like mechanical disturbance were examined, using benthic assemblages of tide‐pools as model system.Response variables were mean abundance values and temporal variances of taxa with different life‐traits. Consistent negative effects of disturbance intensity were observed for the mean cover of long‐living taxa (algal canopies and the polychaeteSabellaria alveolata), whose temporal fluctuations were also reduced by more severe mechanical stress. More resilient taxa (ephemeral algae, mostly green of the genusUlva) increased under enriched conditions, particularly when low‐intensity events were irregularly applied over time. Opposite effects of disturbance intensity depending on nutrient availability occurred on filamentous algae (e.g. red of the genusCeramium). This was probably due to the fact that, although nutrient enrichment stimulated the abundance of both algal groups, when this condition was combined with relatively mild physical disturbance the competitively superior ephemeral green algae tended to become dominant over filamentous red algae. The same did not occur under high intensity of disturbance since it likely damaged large, foliose fronds ofUlva‐like forms more than small, filamentous fronds ofCeramium‐like forms. Grazers were positively affected by nutrients, likely responding indirectly to more food available.A direct relationship between the mean abundance of most organisms and their temporal fluctuations was documented. However, all organisms persisted throughout the study, even under experimental conditions associated to the largest temporal variation in their abundance, likely due to their ability to resist to/quickly recover from, the applied perturbations. Therefore, in systems with great recovery abilities of dominant organisms (e.g. rocky intertidal, grasslands), effects of traits of the regime of disturbance and nutrient enrichment may modulate the fluctuations of populations not through the elimination and substitution of species, but through changes in relative abundances of the same species. This contrasts with the theory that temporal variation in abundance would be directly related to the risk of local extinction. Present findings enable more accurate predictions of the consequences of climatic and non‐climatic scenarios on the biodiversity of marine and terrestrial systems sharing analogous functional traits of organisms. Future more intense physical disturbances are expected to exert negative effects on slow‐growing/recovering species (e.g. habitat‐formers) irrespectively of the temporal patterning of the same disturbances and nutrient inputs. On the contrary, more resistant species (e.g. encrusting algae on rocky shores or below‐ground vegetation in grasslands) are expected to benefit from intense physical disturbance. Species whose abundance is more directly related to the availability of nutrients (e.g. filamentous and ephemeral algae or herbs) are expected to generally increase under enriched conditions, but their ability to eventually become dominant would depend on their ability to grow fast and attain cover large enough to overwhelm any possible control of concomitant disturbance intensity on their abundance. If, such as in the present examined system, virtually all organisms can persist, over the temporal scale of the experiment, under any combination of physical disturbance and nutrient availability, the resulting overall diversity is not predicted to change drastically. Nevertheless, low‐intensity events evenly distributed and high‐intensity events irregularly distributed appear as the conditions supporting the highest richness of taxa, independently of the availability of nutrients.Alay summaryis available for this article.

How climate variations are reflected in root zone storage capacities

Bangiales are photosynthetic organisms that grow in the intertidal zone, a region characterized by fluctuating environmental conditions. The order comprises genera exhibiting two different morphological variations, filamentous and foliose. It was recently demonstrated that the filamentous alga ‘Bangia’ sp. ESS1 possesses the intrinsic ability to “memorize” an experience of prior heat stress to enhance its survival under subsequent, normally lethal, high-temperature conditions via the acquisition of heat stress tolerance. Here, we investigated whether foliose red algae can similarly memorize heat stress to acquire thermotolerance. When Pyropia yezoensis thalli were primed with non-lethal, high-temperature treatments (22 and 25 °C) for 7 days, vegetative cells subsequently triggered with a normally lethal temperature of 30 °C showed dramatically increased survival rates, indicating that P. yezoensis can acquire heat stress tolerance via exposure to non-lethal high temperatures. In addition, when 22 °C-primed thalli were incubated at 15 °C for recovery, vegetative cells survived subsequent incubation at 30 °C; their survival rates varied depending on the duration of recovery. These findings indicate that, like filamentous red algae, the foliose species P. yezoensis memorizes heat stress to acquire tolerance to recurrent thermostress. The identification of heat stress memory in foliose Bangiales lays a foundation for improving the heat stress tolerance of these important algae, supporting the sustainability of the nori mariculture industry.

The five essays of this dissertation combine topics from development and environmental economics. All essays treat the overall topic on how to influence and regulate the production of CO2 emissions. The green house gas CO2 is one of the biggest externalities from human development during the last century. The essays give insight on how changes in local climate conditions affect human wellbeing and what are the potential monetary loses from a rise in average temperature in Latin America. They further analyze the major drivers of CO2 emissions at the household as well as national level and assess how current international climate policy has contributed to reduce CO2 emissions. The last essay gives an overview on how unequal emissions are globally distributed and what will be the future distribution of CO2 emissions when taking different policy scenarios into account. The first essay analyzes how changes in local climatic conditions affect the level of welfare in Latin America. Self reported wellbeing levels are used as a proxy for individual welfare. Subjective wellbeing does not only account for changes in individual income but also for changes in other areas, which determine overall welfare, such as the access to health care or schooling. The study finds that a temperature up to 22 degrees Celsius and rainfall up to 247mm are beneficial for human wellbeing. Higher temperatures or rainfall go in line with welfare loses. A global average warming of 2 degrees Celsius would go in line with welfare loses in Latin America. The second essay analyzes household emissions from consumption, the so-called carbon footprint, in India. The study focuses on the effect of changes in income and the socio- economic composition of the household. A higher household income leads to higher consumption but at the same time the goods, which are consumed change towards lower carbon intensive goods. Still the change in the consumption pattern does not offset the higher carbon footprint due to overall higher consumption rates with rising income. The third essay evaluates how current international climate policy did influence CO2 emissions. Countries with obligations from the Kyoto Protocol did indeed emit on average 6.5% less CO2 than comparable countries with similar income and population growth but without any commitments from Kyoto Protocol. The fourth essay analyzes the main determinant of rising CO2 emissions, namely income. The focus is not on changes in income but on changes in the income distribution within a country and its effect on CO2 emissions. The relationship between carbon dioxide emissions per capita and income inequality is U-shaped: for countries characterized by high income inequality, reductions in income inequality are associated with lower per capita emissions. For less unequal societies, reductions in income inequality are associated with increases in carbon emissions per capita. The fifth essay studies the global distribution of per capita CO2 emissions. The focus is on the effect the energy mix and the sectoral composition have on emission inequality. The decline of heavy manufacturing in OECD countries and the rise of using coal in non- OECD countries led to a decline of global inequality in per capita CO2 emissions. In the long run there is the possibility that emission inequality will rise again. Each essay contributes to the literature in its specific field. They analyze how economic activities (mostly consumption) influence CO2 emissions, which are considered responsible for changes in climatic conditions. At the same time those changes in climatic conditions affect human wellbeing and go in line with monetary loses. National policies such as redistributive policies can have an influence on national CO2 emissions in both directions and have to be well planned. Policies to influence consumption habits towards less CO2 intensive goods could be efficient to regulate CO2 emissions but might only be feasible in richer countries. International climate policies have shown an impact on CO2 emissions among participating countries. International policies can help to get national policies to reduce CO2 emissions on the way.

Relevance of research. At both global and regional levels, climate change has become an indisputable fact, the presence of which has posed to humanity the challenge of solving a number of extremely important and complex tasks related to the development and implementation of a strategy for their practical continued existence. Data base on evaporation and water needs for agricultural crops in the different periods of their growing, depending on the climatic conditions, are the basis for the development of design and formation of operational regimes of water regulation carried out by justifying the necessary methods of water regulation, types, structures and modes of operation of hydro-reclamation systems and calculation of their parameters. Aim of the study is to estimate the changes in water needs during crop cultivation on the drained lands of the Western Polissya in Ukraine in the variable climatic, agricultural and ameliorative conditions for the substantiation of appropriate adaptive decisions to it. To achieve this goal, the authors evaluated the weather and climate conditions in the Western Polissya in Ukraine and calculated the evaporation in the studied conditions, planned and carried out a large-scale computer experiment, based on a complex of predictive-simulation models concerning the basic regimes and technological variables of the hydro-reclamation system parameters, climate conditions, water regime, water regulation technologies and the productivity of drained lands for the schematized natural, agricultural and ameliorative conditions. Research methods. The research methods were based on the application of system theory along with the systematic approach, system analysis and modeling oriented on widespread use of computers and related software in developing modern approaches to the substantiation of technical and technological solutions for water regulation on the drained lands in the conditions of climate change. The object of the study is the drainage system “Birky” in Rivne region, typical for the region in relation to the natural land reclamation conditions. Results of the study and the main conclusions. It was established the needs for additional irrigation of cultivated crops on the drained lands of the Western Polissya in Ukraine in the current weather and climatic conditions. Based on the long-term forecast the vegetative values of the total evaporation and the formation of water needs for the drained lands in the variable climatic, agricultural land reclamation conditions were determined. The technological efficiency of different technologies of the irrigation on the drained lands was evaluated. This approach to the estimation of changes in water needs during crop cultivation in the variable climatic, agricultural and ameliorative conditions allows determining the best technology of water regulation for growing a particular crop under the studied conditions in terms of the most rational use of water resources and the efficiency of system functioning. Prospects. The obtained results can be effectively used for justification of regime and technological decisions in the projects of construction and reconstruction of hydro-reclamation systems of the Western Polissya in Ukraine in the variable climate conditions and developing hydro-technical adaptive measures to the predicted climate change in the region.

Predicting species responses to climate change has become a dynamic field in global change research. A crucial question in this debate is whether-or-not species have been and will be able to respond quickly enough to keep up with changing climatic conditions. Focusing on fossil pollen records and paleoclimatic simulations, this work assesses the change in realized climatic niches (climatic temporal trajectories) of 20 plant taxa over the last 16000 yr, and whether this tracking has been the same for different climatic niche dimensions. Climatic factors showed a consistent trend toward warmer temperatures and higher precipitation. Although the response types varied across taxa, species' realized climatic niches lagged in response to changes in climatic conditions. Temperature niches responded to late Pleistocene (16000-11000 yr ago) climate change, but did so at slower rates than changes in climatic conditions during the same period. In contrast, precipitation niches were relatively stable from 16000 to 11000 yr ago, but still lagged behind changes in climatic conditions. Changes in temperature and precipitation niches eventually stabilized during the Holocene (11000-1000 yr ago). These results underscore how the climatic niche realized at any one moment represents a subset of the climate conditions in which a taxon can persist, particularly during times of fast climatic change. Variability in the rates of temporal trajectories across evaluated climatic variables showed taxa specific responses to changes in climatic conditions over time and emphasizes the need to incorporate variation, intensity, and duration of lag effects in assessments of the possible effects of climatic change.

A comparative quantitative study on the impact of two of the most important factors threatening fresh water resources (urbanization and climate change) is presented. Using the Soil Conservation Service-Curve Number (SCS-CN) model, the individual impacts of the development of urban areas and the changes in the climatic conditions on several components of the urban hydrological cycle (runoff, initial abstraction with a focus on groundwater recharge from precipitations) are assessed with a daily time step at the scale of Algiers during the period 1987–2016. For the presented case study, it was found that the changes in the climatic conditions impacted all three components of the hydrological cycle with a higher magnitude than the development of the urban area. A strong correlation between groundwater recharge (and runoff) and the climatic conditions is observed. Moreover, it is estimated that potential natural groundwater recharge in constructed areas can be higher than that in non-constructed ones; an aspect that can shift with changes in the climatic conditions (particularly the changes in rainfall intensity and frequency).

Today, urban greenery is at the center of attention, especially in the context of climate change. Shaped in large part by natural factors, the herb layer of public parks is a part of urban greenery that is the most sensitive to climate and soil condition changes. In this paper, we present a study intended to answer how resilient is the species composition and herb layer structure against the soil and climate condition changes in parks. To this end, we analyzed Ellenberg and Zarzycki’s ecological index numbers for species recorded in different groups in terms of historical-geographical, life forms, prevalence within the flora of Poland, and relationships with different vegetation types (phytoassociation classes) in comparison to the conditions present in parks. It was found that a large part of various species groups showed an optima and ecological tolerance spectra that went beyond the park conditions, indicating that at least some park vegetation can be expected to show resilience to changing conditions. However, changes in temperature and humidity will alter the composition and structure of the park herb layer. The direction of changes in climate and soil conditions can be decisive for herb layer transformation directions. With rising temperatures, humidity can be crucial. Poor soil moisture conditions will promote an increased share of foreign, synanthropic species, while local natural and semi-natural species will disappear. When climate change that leads to a decrease in temperatures is concerned, it is temperature and not humidity that will be the key factor in the transformation of park herb layer species compositions. The herb layer of Krakow’s parks will have the least resilience to changes in conditions within local non-synanthropic species, rare species and geophytes and to some extent also forest and meadow species.

Geobiocoenological landscape typology, which is used in landscape planning in the Czech Republic, includes vegetation zonation of the landscape. Vegetation zones are determined by climatic conditions. Changes in climatic conditions will probably be manifested in the shift of vegetation zones in the landscape. Mathematical geobiocoenological model of vegetation zonation of the landscape is based on the general ecological relationship between the current vegetation zonation and present climatic conditions and the assumption that this general relationship will be maintained in the future. The paper presents the application of the model using the example of the prediction of changes in climatic conditions for the Norway spruce (the first-generation of the model) and grapevine (the second-generation of the model) in the Czech Republic. In the case of the Norway spruce example, the model shows that the predicted changes in climatic conditions will prevent the cultivation of the spruce in the Czech Republic outside its natural range in mountainous areas. The results of the presented model for grapevine show significant enlargement of areas climatically suitable for growing grapes within the studied area.These examples demonstrate the potential for the application of geobiocoenological landscape typology in the modeling of the effects of climate change in the landscape.

This paper presents research outcomes from an investigation into climate change and urban impacts on climate development in urban regions of the Baltic Sea coast. The cities considered were Rostock and Stockholm, and their surrounding regions. The objectives were: 1) to determine whether significant changes in temperature and precipitation have occurred and, if so, to what extent; and 2) to establish whether there is a noticeable urban heat island effect in Stockholm and the medium-sized city of Rostock. Climatic trends were detected by linear regression and the MannKendall test. Different precipitation trends were detected over the whole period of observation. Average annual temperatures increased significantly in both case studies, particularly from the 1970s with highest trends in winter and lowest in autumn (Rostock) and summer (Stockholm). Although changes in temperature extremes were detected for both regions, no overall long-term trend for precipitation extremes was observed. The average temperature in the city of Rostock (Stockholm) was approximately 0.3˚C to 0.6˚C (1.2˚C) higher than in the surrounding rural areas had seasonal variations, with maxima in the warm season. The main outcomes were that significant changes in climatic conditions, particularly temperature patterns, have been occurring in the case study regions since the 1980s, and that there is a considerable urban heat island effect in both Stockholm and Rostock. This could encourage urban planners to consider specific climatic conditions and small-scale climatic influences also in relatively small coastal urban conglomerates in mid latitudes which can follow from land use changes.

Climate change has been occurring at a rapid rate and is being exacerbated by anthropogenic activities that increase global temperatures and atmospheric concentrations of greenhouse gases such as CO2. This greatly impacts ecosystems worldwide, resulting in more frequent and intense extreme weather events such as heat waves and drought. Understanding how ecosystems respond to elevated CO2 is critical for predicting the impacts of climate change on ecosystem processes, such as their ability to sequester carbon. Temperate ecosystems, in particular, are important in mitigating climate change, holding around 20% of the global plant biomass and approximately 10% of the global terrestrial carbon (Bonan, 2008). However, the capacity of these ecosystems to continue sequestering additional carbon dioxide in the future is uncertain when predicted using current terrestrial biosphere models (TBMs). To address this, improved mechanistic representations of ecosystem states and processes under changing climatic conditions are crucial, as well as the initialisation of the models using real-world observations. In this regard, ecosystem-scale experiments, such as Free-air CO2 enrichment (FACE) experiments, are extremely useful and powerful tools for improving model predictions and have frequently been used for model-data synthesis and ecosystem analysis (Walker et al, 2015).  In this study, we examined the responses of mature temperate forests to rising atmospheric CO2 and changing climatic conditions using the Ecosystem Demography model (ED2), which is a cohort-based terrestrial biosphere model (TBM). We parameterised the model with data collected from the Birmingham Institute of Forest Research, Free-air CO2 Enrichment (BIFoR FACE) experiment site. As the first study using a TBM at BIFoR, this study analysed the model’s capacity to simulate ecosystem responses to elevated CO2 (+150 ppm above ambient) and extreme weather events such as the European drought of 2022 (Gharun et al, 2024). We ran two simulations and compared model outputs against field measurements of key eco-physiological measurements such as maximum rate of carboxylation, soil moisture, and Net Primary Production (NPP). This study demonstrates the capability and the limitations of the TBM to simulate the responses of a mature temperate forest to elevated CO2 conditions under changing and extreme climatic conditions.  

Purpose. To determine promising directions for the development of the technical and technological foundations of soil cultivation in the conditions of climate change. Methods. Monographic, abstract-logical, graph-analytical, induction and deduction, regression analysis of results. Results. Modern soil cultivation technologies are considered, their advantages and disadvantages, development trends are defined. It has been established that climate change will significantly affect the terms of execution of works, the conditions of interaction of working bodies of technical means with the soil environment. The parabolic relationship between traction resistance and soil moisture means that climate change will increase fuel costs for tillage. Therefore, the further search for new technical and technological solutions should be aimed at reducing energy consumption and preventing physical degradation of soils, substantiating structural and functional schemes of technical means for soil cultivation, parameters of working bodies and modes of operation, under which the number of dust particles in the surface layer of the soil will be minimal. Conclusions. The main direction of the development of the technical and technological base for the production of plant products in the conditions of climate change is the harmonization of the interaction of the working bodies of tillage machines with the soil, which will ensure the reduction of physical soil degradation and energy consumption to create a favorable environment for plant development and crop formation. In the conditions of global climate change, agricultural production is being reoriented towards precision farming systems, therefore, crop production technologies should be based on targeted tillage with the simultaneous introduction of a full dose of mineral nutrition into the seed sowing area for the planned harvest, sowing of seeds and preservation of plant residues on the surface of the soil for protection it from overheating and loss of moisture. Keywords: technical means, soil cultivation technologies, interaction of working bodies with the soil, soil moisture, soil resistance, energy consumption, physical soil degradation.

Structural impoverishment of the subtidal vegetation of southeastern Bay of Biscay from 1991 to 2013 in the context of climate change