122 research outputs found

    Challenges and opportunities in the use of ponds and pondscapes as Nature-based Solutions

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    Ponds and “pondscapes” (networks of ponds) are crucial habitats for biodiversity and for delivering multiple benefits to humans, so-called “Nature’s Contribution to People”, such as climate mitigation and adaptation to climate change, creation, and maintenance of habitat for biodiversity, water purification, flood mitigation and cultural benefits (e.g., recreational possibilities). However, ponds are not often considered as Nature-based Solutions to provide all these benefits. In addition, there is insufficient knowledge on how to manage and restore ponds to maximise their role to increase the resilience of ecosystems and society to climate change. To facilitate improved implementation of ponds as Nature-based Solutions for the delivery of a wide range of Nature Contributions to People, it is important to generate and integrate biodiversity, ecosystems, societal, economic and policy knowledge. Hence, there is a need for evidence-based guidance to support the broader use of ponds. Here, we review the role of ponds and pondscapes in delivering Nature’s Contributions to People and provide an overview of the challenges and opportunities for their broader implementation as Nature-based Solutions. Finally, we propose a conceptual framework that can help the implementation of pond Nature-based Solutions, and that outlines future research needs

    Isotope correlations as a probe for freeze-out characterization: central 124Sn+64Ni, 112Sn+58Ni collisions

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    124Sn+64Ni and 112Sn+58Ni reactions at 35 AMeV incident energy were studied with the forward part of CHIMERA multi-detector. The most central collisions were selected by means of a multidimensional analysis. The characteristics of the source formed in the central collisions, as size, temperature and volume, were inspected. The measured isotopes of light fragments (3 <= Z <=8) were used to examine isotope yield ratios that provide information on the free neutron to proton densities.Comment: 4 pages, Contribution to 8th International Conference on Nucleus-Nucleus Collisions, Moscow 200

    Dynamical signals in fragmentation reactions : Time scale determination from three fragments correlations by using the 4 [Pi] Chimera multidetector

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    For fragments emitted in the reactions 124Sn + 64Ni and 112Sn + 58Ni at 35 AMeV, isotopic composition and velocity correlations have been studied as a function of the centrality of the collision, using the 4 Chimera multidetector. We have investigated the time scale for fragments formation, in order to distinguish between prompt dynamical and sequential statistical emission. Promptly emitted light fragments (Z ≤9) produced in the mid-rapidity domain are characterised by larger N/Z ratio and stronger angular anisotropies than those produced in sequential statistical emission. Results are compared with stochastic BNV code simulations obtained for primary fragments. Valuable information on the symmetry term of the nuclear equation of state at sub-saturation densities are obtained

    Isoscaling in neck fragmentation

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    Production of intermediate mass fragments (IMF) has been studied in semi-peripheral 124Sn (35AMeV) + 64Ni and 112Sn (35AMeV) + 58Ni reactions. Our recently proposed new method of an analysis of the neck- like fragmentation processes that provides information on the IMFs time equence and time scale is reviewed. Isotopic analysis of so characterized IMFs gives evidence for neutron enrichment of mid-velocity fragments. A clear isoscaling behavior is found despite the short emission time scale. Evolution of the isoscaling parameters from semi-peripheral to central collisions is discussed

    Isospin effects studied with the CHIMERA detector at 35 Mev/nucleon

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    The yield of light charged particles and intermediate mass fragments is studied for the neutron-rich, 124Sn+64Ni, and neutron-poor, 112Sn+58Ni, reactions at 35MeV/nucleon as a function of the impact parameter. Our main observations are: (i) The yields of 1H, 3He and 4He particles in the neutron-poor system are enhanced with respect to the neutron-rich system and the yield of 3H is suppressed at all impact parameters, (ii) The ratio of 3H to 3He yield is three times larger for neutron poor system, (iii) The N/Z ratio of the emitted intermediate-mass fragments shows dependence on the isospin of the system, (iv) The neutron richness of detected intermediate mass fragments depends strongly on their rapidity. The gross features of the experimental data are reproduced by quantum molecular dynamics model calculations

    Isoscaling in neck fragmentation

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    Production of intermediate mass fragments (IMF) has been studied in semi-peripheral 124Sn (35AMeV) + 64Ni and 112Sn (35AMeV) + 58Ni reactions. Our recently proposed new method of an analysis of the neck- like fragmentation processes that provides information on the IMFs time equence and time scale is reviewed. Isotopic analysis of so characterized IMFs gives evidence for neutron enrichment of mid-velocity fragments. A clear isoscaling behavior is found despite the short emission time scale. Evolution of the isoscaling parameters from semi-peripheral to central collisions is discussed

    The influence of the landscape structure within buffer zones, catchment land use and instream environmental variables on mollusc communities in a medium-sized lowland river

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    The world’s freshwater molluscan fauna is facing unprecedented threats from habitat loss and degradation. Declines in native populations are mostly attributed to the human impact, which results in reduced water quality. The objectives of our survey were to analyse the structure of the mollusc communities in a medium-sized lowland river and to determine the most important environmental variables at different spatial scales, including landscape structure, catchment land use and instream environmental factors that influence their structure. Our survey showed that a medium-sized river, that flows through areas included in the European Ecological Natura 2000 Network Programme of protected sites, provides diverse instream habitats and niches that support 47 mollusc species including Unio crassus, a bivalve of Community interest, whose conservation requires the designation of a special conservation area under the Habitats Directive Natura 2000. This survey showed that mollusc communities are impacted by several environmental variables that act together at multiple scales. The landscape structure within buffer zones, catchment land use and instream environmental variables were all important and influenced the structure of mollusc communities. Therefore, they should all be taken into consideration in the future restoration of the river, future management projects and programmes for the conservation of biodiversity in running waters. The results of this study may be directly applicable for the rehabilitation of river ecosystems and are recommended to stakeholders in their future decision concerning landscape planning, monitoring species and their habitats, conservation plans and management in accordance with the requirements of sustainable development

    An ab initio and AIM investigation into the hydration of 2-thioxanthine

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    <p>Abstract</p> <p>Background</p> <p>Hydration is a universal phenomenon in nature. The interactions between biomolecules and water of hydration play a pivotal role in molecular biology. 2-Thioxanthine (2TX), a thio-modified nucleic acid base, is of significant interest as a DNA inhibitor yet its interactions with hydration water have not been investigated either computationally or experimentally. Here in, we reported an <it>ab initio </it>study of the hydration of 2TX, revealing water can form seven hydrated complexes.</p> <p>Results</p> <p>Hydrogen-bond (H-bond) interactions in 1:1 complexes of 2TX with water are studied at the MP2/6-311G(d, p) and B3LYP/6-311G(d, p) levels. Seven 2TX<sup>...</sup>H<sub>2</sub>O hydrogen bonded complexes have been theoretically identified and reported for the first time. The proton affinities (PAs) of the O, S, and N atoms and deprotonantion enthalpies (DPEs) of different N-H bonds in 2TX are calculated, factors surrounding why the seven complexes have different hydrogen bond energies are discussed. The theoretical infrared and NMR spectra of hydrated 2TX complexes are reported to probe the characteristics of the proposed H-bonds. An improper blue-shifting H-bond with a shortened C-H bond was found in one case. NBO and AIM analysis were carried out to explain the formation of improper blue-shifting H-bonds, and the H-bonding characteristics are discussed.</p> <p>Conclusion</p> <p>2TX can interact with water by five different H-bonding regimes, N-H<sup>...</sup>O, O-H<sup>...</sup>N, O-H<sup>...</sup>O, O-H<sup>...</sup>S and C-H<sup>...</sup>O, all of which are medium strength hydrogen bonds. The most stable H-bond complex has a closed structure with two hydrogen bonds (N(7)-H<sup>...</sup>O and O-H<sup>...</sup>O), whereas the least stable one has an open structure with one H-bond. The interaction energies of the studied complexes are correlated to the PA and DPE involved in H-bond formation. After formation of H-bonds, the calculated IR and NMR spectra of the 2TX-water complexes change greatly, which serves to identify the hydration of 2TX.</p

    Incorporating Ecosystems in the Water-Energy-Food Nexus: Current Perspective and Future Directions

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    Integrated approaches for managing natural resources are needed to meet the increasing demand for freshwater, energy and food, while, in parallel, mitigating and adapting to climate change, maintaining the integrity of ecosystems, and ensuring equitable access to resources. The Water-Energy-Food (WEF) Nexus has been proposed as a cross-sectoral approach to understand, analyse, and manage the complex trade-offs and exploit synergies that arise among these resource sectors. Although not initially included as a component of the Nexus, the importance of ecosystems in supporting water, energy and food security is increasingly recognised by the Nexus community of researchers and practitioners. However, attempts to conceptually integrate Ecosystems into the Nexus have yet to converge into a common framework. A group of natural resources management researchers, system thinkers and ecosystem services experts from the European network COST Action CA20138 NEXUSNET have compiled and investigated the various approaches for integrating ecosystems in the WEF Nexus. By combining literature analysis with interdisciplinary workshops – one of which was held in a hybrid format (in person and online) at the University of Oulu, Finland, in September 2022 – we reveal a multiplicity of concepts utilised to represent, partially or fully, ecosystems in the Nexus, namely “natural environment”, “ecosystem services” and “biodiversity”. Disparity was also found in the role attributed to ecosystems in the Nexus framework, being it an underlying layer from which resources for Nexus sectors are extracted or the pillar of an expanded Nexus system – i.e., the WEF-Ecosystems Nexus. Through this collaborative effort, we present possible advantages and disadvantages of adopting differential WEF-Ecosystems Nexus approaches, highlighting their potential complementarity and integration to support future advancement of Nexus research. In the oral presentation, we will show our preliminary findings and encourage the exchange of ideas and feedback from the different scientific disciplines present at the CEMEPE Conference.Tenth International Conference on Environmental Management, Engineering, Planning and Economics (CEMEPE) & SECOTOX Conference organized by: Division of Hydraulics and Environmental Engineering, Department of Civil Engineering, Aristotle University of Thessaloniki and Society of Ecotoxicology and Environmental Safety (SECOTOX), Skiathos island, Greece, 2023
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