Ecosystem properties of acid grasslands along a gradient of nitrogen deposition

Sixty-eight randomly selected grasslands belonging to the National Vegetation Classification group U4 (Festuca ovina-Agrostis capillaris-Galium saxatile grassland) were studied during the summers of 2002 and 2003 along a gradient of atmospheric N deposition ranging from 6 to 36 kg N ha-1 yr-1 to investigate potential damage caused by acidification and eutrophication. At each site vegetation was surveyed and samples were taken from the topsoil and subsoil. Above-ground plant material was collected from three species: Agrostis capillaris, Galium saxatile and Rhytidiadelphus squarrosus. Species richness showed a negative linear trend with N deposition, with a reduction of 1 species for every 2.5 kg N ha-1 yr-1. At the current mean N deposition in Europe this gave a reduction in species richness of 23% from a projected pristine condition. Forbs accounted for the majority of this decline, showing reductions in both cover and abundance along the N-deposition gradient. Grasses showed a decrease in species richness, but an increase in cover, indicating increased dominance of a few species. Using canonical correspondence analysis, several individual species were identified as being positively and negatively associated with N deposition. Soil pH declined along the N-deposition gradient. This was also associated with increased mobilisation of aluminium, arsenic and lead. Nitrate concentration in the soil did not increase with increasing N inputs, possibly due to rapid plant uptake and its mobility in the soil profile. Soil extractable ammonium concentration showed a significant positive correlation with N inputs. A weak relationship was also identified between the C:N ratio in the soil and N inputs. Potential ammonium mineralization showed considerable variation across the sites. There was no correlation between aboveground tissue Nand N deposition for any of the three species examined. A weak correlation was identified between tissue N and soil C:N for G. saxatile. Tissue N:P ratios gave no clear indication of nutrient limitation. The relative merits of different indicators of N-deposition are discussed

Addition of multiple limiting resources reduces grassland diversity

Niche dimensionality provides a general theoretical explanation for biodiversity—more niches, defined by more limiting factors, allow for more ways that species can coexist1. Because plant species compete for the same set of limiting resources, theory predicts that addition of a limiting resource eliminates potential trade-offs, reducing the number of species that can coexist2. Multiple nutrient limitation of plant production is common and therefore fertilization may reduce diversity by reducing the number or dimensionality of belowground limiting factors. At the same time, nutrient addition, by increasing biomass, should ultimately shift competition from belowground nutrients towards a one-dimensional competitive trade-off for light3. Here we show that plant species diversity decreased when a greater number of limiting nutrients were added across 45 grassland sites from a multi-continent experimental network4. The number of added nutrients predicted diversity loss, even after controlling for effects of plant biomass, and even where biomass production was not nutrient-limited. We found that elevated resource supply reduced niche dimensionality and diversity and increased both productivity5 and compositional turnover. Our results point to the importance of understanding dimensionality in ecological systems that are undergoing diversity loss in response to multiple global change factors

Towards the integration of urban planning and biodiversity conservation through collaboration

Despite aspirations to halt biodiversity loss by 2020 under the Aichi Biodiversity Targets, urban development continues to negatively impact UK wildlife and habitats. Reasons behind continued biodiversity decline are examined through the use of semi-structured interviews with ecologists, statutory regulators and land developers.. It is found that despite strict legislation and best practice, for both planning and ecology, there is still much room for subjectivity regarding the protection of specific ecological features and the implementation of the mitigation hierarchy. Interviews also revealed that such subjectivity often facilitates the prioritisation of commercial over ecological benefits during site design. Furthermore, many felt an over reliance on the protection of individual animals, as opposed to maintaining functional connectivity for conservation of wider populations was detrimental to both the development industry and ecology. Our findings support the case for further research into the development of innovative geographical information systems to allow spatial deliberation, and collaborative decision-making between the three stakeholder groups

Determining The Cost Effectiveness Of Solutions To Diffuse Pollution: Developing A Model To Assess In-Field Mitigation Options for Phosphorous and Sediment Loss

The European Union Water Framework Directive requires governments to set water quality objectives based on good ecological status. This includes specific requirements to control diffuse pollution. Diffuse phosphorous (P) pollution plays a pivotal role in influencing water quality with losses of P associated with soil particles often linked to soil erosion. The Mitigation Options for Phosphorus and Sediment (MOPS) project, using three case study sites, is investigating the cost effectiveness of specific control measures in terms of mitigating sediment and P loss from combinable crops. The analysis is conducted at the farm level using a simple spreadsheet model. Further development of the model will allow the results to be extrapolated to generic regional farm typologies. Results from the initial farm level analysis suggest that some mitigation options may not be cost effective in reducing diffuse pollution, however, that other options may be very cost effective.Resource /Energy Economics and Policy,

Personal nitrogen footprint tool for the United Kingdom

The global nitrogen (N) cycle has been transformed by human use of reactive N as a consequence of increased demand for food and energy. Given the considerable impact of humans on the N cycle, it is essential that we raise awareness amongst the public and policy makers as this is the first step in providing individuals and governments the opportunity to reduce their impact on the N cycle and reduce the environmental and health consequences of N pollution. Here we describe an N footprint tool for the UK developed as part of the N-PRINT program. The current per capita N footprint in the UK is 27.1 kg N per capita per year with food production constituting the largest proportion of the footprint (18.0 kg N per capita per year). Calculating an N footprint for 1971 (26.0 kg N per capita per year) demonstrates that per capita N footprints have increased slightly. The average UK footprint is smaller than that found in the USA but is higher than the Netherlands and Germany. Scenario analysis demonstrates that reducing food protein consumption to the levels recommended by the FAO and World Health Organization reduces the overall N footprint by 33%. Consuming a vegetarian diet and consuming only sustainable food both decreased the N footprint by 15% but changes in energy use have a much smaller impact

How long do ecosystems take to recover from atmospheric nitrogen deposition?

Atmospheric nitrogen (N) deposition is a considerable threat to biodiversity and ecosystem function globally. Many experimental N additions and studies using gradients of ambient deposition have demonstrated impacts on plant species richness, diversity and composition in a broad range of habitats together with changes in soil biogeochemistry. In the last two decades levels of N deposition have begun to decline in some parts of Europe but it is currently difficult to assess the extent to which reductions in N deposition will result in recovery within semi-natural habitats. There have been a number of investigations using the cessation of N additions in long-term experiments, monitoring in areas where ambient deposition has declined, transplants to situations with lower N inputs and roof experiments where rain is collected and cleaned. This review collates evidence from experiments in grasslands, forests, heathlands and wetlands where N additions have ceased or where N inputs have been reduced to assess how likely it is that habitats will recover from N deposition. The results of the majority of studies suggest that vegetation species composition, below-ground communities and soil processes may be slow to recover whereas some soil variables, such as nitrate and ammonium concentrations, can respond relatively rapidly to reductions in N inputs. There are a number of barriers to recovery such as continued critical load exceedance and lack of seed bank or local seed source, and there is the potential for vegetation communities to reach an alternative stable state where species lost as a consequence of changes due to N deposition may not be able to recolonise. In these cases only active restoration efforts can restore damaged habitats

Science Hunters: An inclusive approach to engaging with science through Minecraft

Science Hunters is an outreach project which employs the computer game Minecraft to engage children with scientific learning and research through school visits, events, and extracurricular clubs. We principally target children who may experience barriers to accessing Higher Education, including low socioeconomic status, being the first in their family to attend university, and disability (including Special Educational Needs). The Minecraft platform encourages teamwork and makes science learning accessible and entertaining for children, irrespective of background. We employ a flexible approach that adapts to the needs of the users. More than 8000 children have been engaged in the first four years, with overwhelmingly positive feedback

The effects of minimal tillage, contour cultivation and in-field vegetative barriers on soil erosion and phosphorus loss.

Runoff, sediment, total phosphorus and total dissolved phosphorus losses in overland flow were measured for two years on unbounded plots cropped with wheat and oats. Half of the field was cultivated with minimum tillage (shallow tillage with a tine cultivator) and half was conventionally ploughed. Within each cultivation treatment there were different treatment areas (TA). In the first year of the experiment, one TA was cultivated up and down the slope, one TA was cultivated on the contour, with a beetle bank acting as a vegetative barrier partway up the slope, and one had a mixed direction cultivation treatment, with cultivation and drilling conducted up and down the slope and all subsequent operations conducted on the contour. In the second year, this mixed treatment was replaced with contour cultivation. Results showed no significant reduction in runoff, sediment losses or total phosphorus losses from minimum tillage when compared to the conventional plough treatment, but there were increased losses of total dissolved phosphorus with minimum tillage. The mixed direction cultivation treatment increased surface runoff and losses of sediment and phosphorus. Increasing surface roughness with contour cultivation reduced surface runoff compared to up and down slope cultivation in both the plough and minimum tillage treatment areas, but this trend was not significant. Sediment and phosphorus losses in the contour cultivation treatment followed a very similar pattern to runoff. Combining contour cultivation with a vegetative barrier in the form of a beetle bank to reduce slope length resulted in a non-significant reduction in surface runoff, sediment and total phosphorus when compared to up and down-slope cultivation, but there was a clear trend towards reduced losses. However, the addition of a beetle bank did not provide a significant reduction in runoff, sediment losses or total phosphorus losses when compared to contour cultivation, suggesting only a marginal additional benefit. The economic implications for farmers of the different treatment options are investigated in order to assess their suitability for implementation at a field scale

Change and grassroots movement: re-conceptualizing women's hockey governance in Canada

Sherpa Romeo yellow journal. Permission to retain in OPUS granted by publisher.In Canada, female hockey governance structures vary as different regions of the country may better suit integrated or partially-integrated governance approaches based upon their unique local histories and individual dynamics. Indeed, the Ontario Women’s Hockey Association (OWHA) is the only female hockey provincial association in Canada that endorses and endeavours to maintain a separatist philosophy. However, women’s hockey governance in Canada as a whole has not progressed in a manner where the authority of female hockey participants and leaders has increased. This paper initiates dialogue about women’s sport governance by utilising women’s hockey in Canada and specifically a case study of the OWHA, as a context in which to develop a new perspective and renew efforts to place women’s sport governance on the agenda. In order to develop a sport and governance dialogue for women’s hockey specifically and women’s sport more broadly, we present a theoretical discussion that integrates critical feminist and grassroots movement perspectives.Ye

“So we can’t bring a volcano into the classroom…” Communicating geosciences through digital media

There are many fascinating, exciting and important aspects of geoscience that we just cannot physically bringinto classrooms and public engagement events in all their glory. Volcanic eruptions, using drones to combatenvironmental crime, museum exhibits of dinosaur remains. . . and so we must find other ways in which to capturethe imagination and attention of the scientists of the future, and make science and scientists accessible andrelatable to them.How best to do this? What do we need to consider? What do audiences want? Do our approaches actuallywork? Research and practice from three different projects, at varying stages of development, which use computerbased applications to engage public audiences with geosciences give us some insight into effective use of novelcommunication methods in this area.Science Hunters (1) is a successful and well-established outreach project which uses the widely popularcomputer game Minecraft to engage children with science. Run by environmental scientists, there is a heavy focuson geosciences (2). Minecraft is akin to Lego on a computer, but with many more building possibilities. Featuresand processes are relatable to those in the real world, which, along with the widespread appeal of the game, makeit an ideal tool for communicating scientific topics. The Science Hunters approach is highly effective in engagingchildren, as shown by project evaluation data.Science for Environment Policy (3) communicates environmental research findings in easy-to-understandformats to policymakers and citizens across Europe, strengthening the connection between scientific evidence andpolicy, and is evaluated annually, charting the impact of an element of its digital media. Recent project videoshave showcased a variety of geoscience issues in a variety of formats as part of the public service. An evaluationundertaken with students of relevant environmental sciences gives insights into which of these most formats aremost appealing, and likely to be used more widely.The Virtual Natural History Museum (4) is a novel engagement project that places digitised museum resources back on public display. The website takes the form of a giant computer game museum which visitors canexplore, viewing palaeontological multimedia. This grants any community with an internet connection immediateaccess to world-class natural history collections, providing everyone with the opportunity to learn about fossilsand past environments. The project is currently in development for use in schools, presenting an opportunity tofind out more about how teachers respond to such tools. Research into teachers’ views and ideas about how such aresource might be used in schools is widely applicable to other sciences.1 www.lancaster.ac.uk/sciencehunters2 Hobbs et al., 2018. Digging Deep into Geosciences with Minecraft. Eos, 99(11), 24-293 http://ec.europa.eu/environment/integration/research/newsalert/index_en.htm4 http:///www.vnhm.or