Subtitle: TT Club's director of global risk assessment, Laurence Jones, suggests ways for port operators to minimise accidents and improve performance.
A major overhaul of the property tax system in 2013 in the City of Philadelphia has generated significant variations in the amount of property taxes across properties. This exogenous policy shock provides a unique opportunity to identify the causal effects of gentrification, which is often accompanied by increased property values, on homeowners’ tax payment behavior and residential mobility. The analysis, based on a difference-in-differences framework, suggests that gentrification leads to a higher risk of delinquency on homeowners’ tax bills on average, but there was no sign of a large-scale departure of elderly or long-term homeowners in gentrifying neighborhoods within five years after adoption of the new policy. While tax delinquencies were somewhat inflated by appeals for reassessments, programs designed to provide tax relief for long-term homeowners help mitigate the risk of tax delinquencies and displacement. Findings from this study help researchers, policymakers, and practitioners better understand the mechanisms through which gentrification may impact long-term homeowners and the effectiveness of policies to mitigate these tax burdens and displacement.
Abstract Questions Hydrological niche segregation is widespread and has been found across a range of different habitats. Different plant species can occupy distinct hydrological niches, and as a result fine‐scale variability in hydrology can structure plant communities. However, these patterns may not be as clear in habitats where differences in hydrology are more short‐lived, such as coastal dune slacks. We explored the extent that the hydrological regime structures dune slack plant communities. Location Ainsdale Coastal Sand Dune National Nature Reserve, UK. Methods Six hundred quadrats were surveyed, 100 in each of six coastal dune slacks. Water table levels are recorded monthly in each slack. Metrics summarising hydrological regime were calculated and adjusted for each quadrat based on elevation. We tested the relationship between water table depth, plant communities and topography across and within dune slacks. Results Half (three) of the slacks showed a significant influence of hydrology on plant community composition. The three that did not were the ones that varied least topographically and contained less diverse plant communities. We also provide indirect evidence of niche segregation by modelling species‐specific responses between mean water table depth and probability of species presence. Conclusions We demonstrate that hydrology is a dominant driver of plant community composition across dune slacks. However, plant communities are not always structured by hydrology, demonstrating the complexity of vegetation patterns. Topographic variation appears to impact plant community patterns, as do successional processes, highlighting the need to create diverse habitats for slack restoration and management.
1. Given the widespread impacts on habitats in the UK it is essential to understand how habitat management measures could mitigate N deposition impacts and promote recovery. This project reviews the effectiveness of ‘on-site’ land management methods to mitigate nitrogen deposition impacts on sensitive habitats; assesses what effect current management practice has on habitat response to nitrogen deposition; considers how measures may be affected by climate change; and recommends realistic and practical management measures for different habitat types which could be used to mitigate nitrogen impacts or speed recovery. 2. The potential for management to mitigate N deposition impacts was considered across the following broad habitats: broadleaved, mixed and yew woodland & (natural) coniferous woodland; neutral grassland; calcareous grassland; acid grassland; dwarf shrub heath; bog; coastal dunes and slacks; other coastal habitats. For all habitats we were able to identify management techniques with some potential to mitigate N deposition impacts. 3. Management techniques may improve habitat suitability (e.g. control dominant species), remove nitrogen from the system, or both. 4. However, all management techniques also have unintended consequences meaning that their implementation might conflict with other conservation priorities. 5. There are a range of schemes and handbooks providing habitat management advice in the UK. The following techniques were reviewed in detail: grazing; cutting; burning; fertilisation; liming; hydrological management; scrub and tree management; disturbance. 6. Current management may already be partially offsetting the impact of N deposition. 7. Management for N is unlikely to make habitats more vulnerable to climate change. There is complementarity in the management options required to tackle N deposition and climate change. The frequency or intensity of measures such as grazing, cutting or burning will all need to increase. Regional variation in climate change may lead to different emphasis of management options in the wetter north west and the drier south east. 8. Climate change will alter habitat sensitivity to N deposition, via changes in ecosystem processes. Overall, climate change will make woodlands less sensitive to N deposition, but will make heathlands more sensitive to N deposition. Effects on other habitats have not yet been evaluated. 9. There is some potential for mitigating the impacts of N deposition through on-site management although this varies greatly between habitat and management practice. It is likely that small changes in management and adherence to appropriate guidelines could partially improve habitat suitability and/or increase N removal. 10. The majority of management practices do not remove significant quantities of N (with the exception of removing biomass or topsoil). Furthermore, management of a suitable intensity to remove sufficient N to fully offset N added by atmospheric deposition is likely to damage the habitat and result in a number of unintended consequences. 11. Further research is needed to determine the impacts of individual management practices on the N budget in different habitats. Further research is also needed to explore the potential for novel management techniques to remove N from sites. 12. For an individual site where N is identified as a pressure, a manager can look at current management and compare this with the management recommendations in the report to make changes where appropriate. 13. All management recommendations that remove N from the site move it elsewhere and have the potential for unintended consequences. Consequently there is no substitute for reducing the amount of N deposited onto a site which can only be achieved through emission controls.
Niniejszy dokument policy brief (D4.1) został opracowany w ramach projektu Horyzont Europa PLAN-B (Umowa grantowa nr 101135308) we współpracy z projektem AquaPLAN (Umowa grantowa nr 101135471). Dokument ten dostarcza strategicznych wskazówek dla Unii Europejskiej w zakresie podejmowania działań przeciwdziałających zanieczyszczeniu światłem sztucznym, uznając jego niekorzystny wpływ na środowisko, ujednolicając wysiłki i zapewniając ramy dla skoordynowanych działań krajowych, a także promując regulacje i zarządzanie sztucznym światłem w nocy (ALAN) oparte na dowodach naukowych. Aby wesprzeć działania polityczne mające na celu redukcję zanieczyszczenia światłem, zachęca się osoby prywatne do podpisania formularza poparcia, natomiast organizacje mogą poprzeć inicjatywę, podpisując list poparcia, który na żądanie można uzyskać od osób kontaktowych wymienionych w dokumencie informacyjnym dotyczącym polityki. Yakushina, Y., Klenke, R., Fletcher, D., Jones, L., Nascimento, A. T. A., Teixeira, C. P., Goulart, V. D. L. R, Maggi, E., Hoelker, F., Barnett, C., Tysiac, P., Sanchez de Miguel, A., Sheriff, G., Lomas, M. J., Van Hoorick, G., & Wood, M.D. (2025). Restoring the night: A policy agenda for light pollution mitigation in Europe. Policy brief written by thePLAN-B project (Horizon Europe No. 101135308) and the AquaPLAN project (Horizon Europe No. 101135471). Przetłumaczone przez Translated by Paweł Tysiąc, Karolina M. Zielińska-Dąbkowska & Katarzyna Bobkowska. Zenodo. Disclaimer This publication was produced under the Horizon Europe programme (Grant Agreement No. 101135308) as part of the PLAN-B project. The content reflects only the views of the authors. The European Commission is not responsible for any use that may be made of the information contained herein. The information is provided “as is” without warranty of fitness for a particular purpose. The PLAN-B Consortium accepts no liability for any direct, indirect, or consequential damages arising from its use. This is a Polish translation of the Policy Brief “Restoring the Night: A Policy Agenda for Light Pollution Mitigation in Europe” (published June 2025) (access the original version here).
Whereas much is known of the short‐term growth response to elevated atmospheric CO 2 concentrations, [CO 2 ] elev , there is relatively little information on how the response of native species is modified by temperature, despite the fact that an increase in global mean temperature is expected to accompany the rise in [CO 2 ]. In this study, five functionally related annual native species were exposed to different combinations of ambient and elevated [CO 2 ] and temperatures in order to assess their response in terms of growth and allometry. Fast‐growing annuals were selected for the study because their growth responses could be assessed over a major portion of the plant's life cycle and in as short a period as 8 wk. Plants were grown in eight hemi‐spherical glasshouses, programmed to track outside ambient conditions and provide a replicated experimental design. Treatments comprised (i) current ambient [CO 2 ] and temperature, (ii) elevated [CO 2 ] (ambient+34 kPa), and ambient temperature (iii) ambient [CO 2 ] and elevated temperature (ambient+3°C) and (iv) elevated [CO 2 ] and elevated temperature (T°C elev ). All five species responded positively to [CO 2 ] elev , although the response was statistically significant for only one, Poa annua L. Averaged over all five species, [CO 2 ] elev increased total plant biomass by 25% ( P =0·005) at 56 d, reflecting a proportionally greater increase in leaf and stem mass relative to root weight. Elevated [CO 2 ] had no effect on leaf area, either at the individual species level or overall. Elevated T°C, by contrast, had little effect on shoot growth but increased root mass on average by 43% and leaf area by 22%. Few interactions between elevated [CO 2 ] and T°C were observed, with the CO 2 response generally greater at elevated than ambient T°C. Both [CO 2 ] elev and T°C elev resulted in a transient increase in relative growth rate, ( rgr ), during the first 14 d exposure and a 3°C increase in temperature had no effect on the duration of the response. CO 2 stimulation of growth operated through a sustained increase in net assimilation rate. ( nar ), although the potential benefit to rgr was offset by a concurrent decline in leaf area ratio ( lar ), as a result of a decrease in leaf area per unit leaf mass ( sla ). The response to T°C elev was generally opposite of that to [CO 2 ] elev . For example, T°C elev increased lar through an increase in sla and this, rather than any effect on nar , was the major factor responsible for the stimulation of rgr . Allometric analysis of CO 2 effects revealed that changes in allocation observed at individual harvests were due solely to changes associated with plant size. Elevated T°C, by contrast, had a direct effect on allocation patterns to leaves, with an increase in leaf area expansion relative to whole plant mass during the initial stages of growth and subsequent increased allocation of biomass away from leaves to other regions of the plant. No change in the allometric relation between roots and shoots were observed at either elevated [CO 2 ] or T°C. We conclude, therefore, that allocation of biomass and morphological characteristics such as sla , are relatively insensitive to [CO 2 ], at least when analysed at the whole‐plant level, and where changes have been observed, these are the product of comparing plants of the same age but different size.
Dune slacks are biodiverse seasonal wetlands within sand dune systems, strongly influenced by the dynamics of the local groundwater regime. Future climate predictions indicate strong adverse impact on the hydrology and therefore ecology of these wetland ecosystems. In this study we aimed to find the most appropriate hydrological and ecological indicators to summarise dune slack plant community responses to hydrology over multiple years. We evaluated 80 hydrological metrics (weighted and un-weighted median, mean, minimum, maximum, mean spring level, averaged over 1–8 year duration, and 5 additional 1-year metrics) against plant community responses (variants of Ellenberg EbF moisture indicator). The data were drawn from 453 relevées in 17 dune slacks, using permanent quadrats and co-located piezometers, set up in 2010 with vegetation monitoring repeated six times until 2019. Within our study we found a strong relationship between multiple hydrology metrics and the plant community response, but this displayed inter-annual variation with different patterns and correlations between years. The best performing hydrology metric was the unweighted 5-year average mean spring water level (MSL), linked to unweighted mean EbF using vascular plant species only. Maximum water level (MAX) also performed well, but MSL was preferred as MAX can be enhanced or truncated by topography leading to anomalies for individual slacks. MSL is also flexible to implement within manual monitoring programmes, which could be targeted to 3-months per year over the spring as a minimum requirement. These findings provide simpler metrics for site managers to monitor potential hydrology and vegetation responses to climate change.
