287 results on '"Spears, B.M."'
Search Results
2. Assessing Pro-environmental Behaviour in Relation to the Management of Pollution from Private Sewage Systems
- Author
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Brownlie, Will Joseph, Spears, B.M., Patidar, Sandhya, Linda, May, and Roaf, Susan
- Published
- 2015
3. Impacts of multiple stressors on freshwater biota across spatial scales and ecosystems
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Birk, S., Chapman, D., Carvalho, L., Spears, B.M., Andersen, H.E., Argillier, C., Auer, S., Baattrup-Pedersen, A., Banin, L., Beklioglu, M., Bondar-Kunze, E., Borja, A., Branco, P., Bucak, T., Buijse, A.D., Cardoso, A.C., Couture, R.M., Cremona, F., Zwart, D. de, Feld, C.K., Ferreira, M.T., Feuchtmayr, H., Gessner, M.O., Gieswein, A., Globevnik, L., Graeber, D., Graf, W., Gutiérrez-Cánovas, C., Hanganu, J., Iskin, U., Järvinen, M., Jeppesen, E., Kotamäki, N., Kuijper, M., Lemm, J.U., Lu, S., Solheim, A.L., Mischke, U., Moe, S.J., Noges, P., Noges, T., Ormerod, S.J., Panagopoulos, Y., Phillips, G., Posthuma, L., Pouso, S., Prudhomme, C., Rankinen, K., Rasmussen, J.J., Richardson, J., Sagouis, A., Santos, J.M., Schäfer, R.B., Schinegger, R., Schmutz, S., Schneider, S.C., Schülting, L., Segurado, P., Stefanidis, K., Sures, B., Thackeray, S.J., Turunen, J., Uyarra, M.C., Venohr, M., Ohe, P.C. von der, Willby, N., Hering, D., Birk, S., Chapman, D., Carvalho, L., Spears, B.M., Andersen, H.E., Argillier, C., Auer, S., Baattrup-Pedersen, A., Banin, L., Beklioglu, M., Bondar-Kunze, E., Borja, A., Branco, P., Bucak, T., Buijse, A.D., Cardoso, A.C., Couture, R.M., Cremona, F., Zwart, D. de, Feld, C.K., Ferreira, M.T., Feuchtmayr, H., Gessner, M.O., Gieswein, A., Globevnik, L., Graeber, D., Graf, W., Gutiérrez-Cánovas, C., Hanganu, J., Iskin, U., Järvinen, M., Jeppesen, E., Kotamäki, N., Kuijper, M., Lemm, J.U., Lu, S., Solheim, A.L., Mischke, U., Moe, S.J., Noges, P., Noges, T., Ormerod, S.J., Panagopoulos, Y., Phillips, G., Posthuma, L., Pouso, S., Prudhomme, C., Rankinen, K., Rasmussen, J.J., Richardson, J., Sagouis, A., Santos, J.M., Schäfer, R.B., Schinegger, R., Schmutz, S., Schneider, S.C., Schülting, L., Segurado, P., Stefanidis, K., Sures, B., Thackeray, S.J., Turunen, J., Uyarra, M.C., Venohr, M., Ohe, P.C. von der, Willby, N., and Hering, D.
- Abstract
Contains fulltext : 228877pub.pdf (Publisher’s version ) (Closed access) Contains fulltext : 228877pos.pdf (Author’s version postprint ) (Open Access)
- Published
- 2020
4. Eutrophication and restoration in temperate lakes
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May, L., Olszewska, J., Gunn, I.D.M., Meis, S., Spears, B.M., May, L., Olszewska, J., Gunn, I.D.M., Meis, S., and Spears, B.M.
- Abstract
Eutrophication affects many lakes and reservoirs worldwide. It is caused by excessive amounts of nutrients entering waterbodies from their catchments, mainly due to human activity. The main sources of these nutrients are discharges from industry and wastewater treatment systems, and agricultural runoff. The water quality problems caused by eutrophication, such as harmful algal blooms, affect the sustainable use of lakes for agriculture, fisheries, recreation, tourism and water supply. They also degrade habitat quality and threaten biodiversity. A range of methods for improving lake water quality are explored, including catchment management and in-lake restoration measures. The potential impacts of these on lake biodiversity are explored, including species interactions and ecosystem feedbacks that may confound the recovery process. A particular challenge is the fact that achieving sustainable recovery may take many years, mainly due to the impact of legacy pollution problems. This must be taken into account when planning and implementing eutrophication management options, because these slow recovery periods can exceed the timescales that people are willing to accept. While this review focuses on the many well documented studies of restoration and recovery processes in temperate lakes, it also highlights the need for similar research on tropical and sub-tropical systems.
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- 2020
5. Unified concepts for understanding and modelling turnover of dissolved organic matter from freshwaters to the ocean: the UniDOM model
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Anderson, T.R., Rowe, E.C., Polimene, L., Tipping, E., Evans, C.D., Barry, C.D.G., Hansell, D.A., Kaiser, K., Kitidis, V., Lapworth, D.J., Mayor, D.J., Monteith, D.T., Pickard, A.E., Sanders, R.J., Spears, B.M., Torres, R., Tye, A.M., Wade, A.J., Waska, H., Anderson, T.R., Rowe, E.C., Polimene, L., Tipping, E., Evans, C.D., Barry, C.D.G., Hansell, D.A., Kaiser, K., Kitidis, V., Lapworth, D.J., Mayor, D.J., Monteith, D.T., Pickard, A.E., Sanders, R.J., Spears, B.M., Torres, R., Tye, A.M., Wade, A.J., and Waska, H.
- Abstract
The transport of dissolved organic matter (DOM) across the land-ocean-aquatic-continuum (LOAC), from freshwater to the ocean, is an important yet poorly understood component of the global carbon budget. Exploring and quantifying this flux is a significant challenge given the complexities of DOM cycling across these contrasting environments. We developed a new model, UniDOM, that unifies concepts, state variables and parameterisations of DOM turnover across the LOAC. Terrigenous DOM is divided into two pools, T1 (strongly-UV-absorbing) and T2 (non- or weakly-UV-absorbing), that exhibit contrasting responses to microbial consumption, photooxidation and flocculation. Data are presented to show that these pools are amenable to routine measurement based on specific UV absorbance (SUVA). In addition, an autochtonous DOM pool is defined to account for aquatic DOM production. A novel aspect of UniDOM is that rates of photooxidation and microbial turnover are parameterised as an inverse function of DOM age. Model results, which indicate that ~ 5% of the DOM originating in streams may penetrate into the open ocean, are sensitive to this parameterisation, as well as rates assigned to turnover of freshly-produced DOM. The predicted contribution of flocculation to DOM turnover is remarkably low, although a mechanistic representation of this process in UniDOM was considered unachievable because of the complexities involved. Our work highlights the need for ongoing research into the mechanistic understanding and rates of photooxidation, microbial consumption and flocculation of DOM across the different environments of the LOAC, along with the development of models based on unified concepts and parameterisations.
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- 2019
6. Assessment of sediment phosphorus capping to control nutrient concentrations in English lakes
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Spears, B.M., Andrews, C., Banin, L., Carvalho, L., Cole, S., De Ville, M., Gunn, I.D.M., Ives, S., Lawlor, A., Leaf, S., Lofts, S., Maberly, S.C., Madgwick, G., May, L., Moore, A., Pitt, J., Smith, R., Waters, K., Watt, J., Winfield, I.J., Woods, H., Spears, B.M., Andrews, C., Banin, L., Carvalho, L., Cole, S., De Ville, M., Gunn, I.D.M., Ives, S., Lawlor, A., Leaf, S., Lofts, S., Maberly, S.C., Madgwick, G., May, L., Moore, A., Pitt, J., Smith, R., Waters, K., Watt, J., Winfield, I.J., and Woods, H.
- Abstract
This project investigated the effectiveness of a technique for stopping the release of phosphorus from lake sediments.
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- 2018
7. Assessment of sediment phosphorus capping to control nutrient concentrations in English lakes - project summary
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Cole, S., Spears, B.M., Cole, S., and Spears, B.M.
- Abstract
Project summary - full report available separately. This project investigated the effectiveness of a technique for stopping the release of phosphorus from lake sediments.
- Published
- 2018
8. Guiding principles for the development and application of solid-phase phosphorus adsorbents for freshwater ecosystems
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Douglas, G.B., Hamilton, D.P., Robb, M.S., Pan, G., Spears, B.M., Luring, M., Douglas, G.B., Hamilton, D.P., Robb, M.S., Pan, G., Spears, B.M., and Luring, M.
- Abstract
Whilst a diverse array of phosphorus (P)-adsorbent materials is currently available for application to freshwater aquatic systems, selection of the most appropriate P-adsorbents remains problematic. In particular, there has to be a close correspondence between attributes of the P-adsorbent, its field performance and the management goals for treatment. These management goals may vary from a rapid reduction in dissolved P to address seasonal enrichments from internal loading, targeting external fluxes due to anthropogenic sources, or long-term inactivation of internal P inventories contained within bottom sediments. It also remains a challenge to develop new methods and materials that are ecologically benign and cost-effective. We draw on evidence in the literature and the authors’ personal experiences in the field, to summarise the attributes of a range of P-adsorbent materials. We offer ‘guiding principles’ to support practical use of existing materials and outline key development needs for new materials.
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- 2016
9. A meta-analysis of water quality and aquatic macrophyte responses in 18 lakes treated with lanthanum modified bentonite (PHOSLOCK®)
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Spears, B.M., Mackay, E., Yasseri, S., Gunn, I.D.M., Waters, K.E., Andrews, C., Cole, S., de Ville, M., Kelly, M., Meis, S., Moore, A.L., Nurnberg, G.K., van Oosterhout, Frank, Lurling, M.F.L.L.W., Spears, B.M., Mackay, E., Yasseri, S., Gunn, I.D.M., Waters, K.E., Andrews, C., Cole, S., de Ville, M., Kelly, M., Meis, S., Moore, A.L., Nurnberg, G.K., van Oosterhout, Frank, and Lurling, M.F.L.L.W.
- Abstract
Lanthanum (La) modified bentonite is being increasingly used as a geo-engineering tool for the control of phosphorus (P) release from lake bed sediments to overlying waters. However, little is known about its effectiveness in controlling P across a wide range of lake conditions or of its potential to promote rapid ecological recovery. We combined data from 18 treated lakes to examine the lake population responses in the 24 months following La-bentonite application (range of La-bentonite loads: 1.4-6.7 tonnes ha-1) in concentrations of surface water total phosphorus (TP; data available from 15 lakes), soluble reactive phosphorus (SRP; 14 lakes), and chlorophyll a (15 lakes), and in Secchi disk depths (15 lakes), aquatic macrophyte species numbers (6 lakes) and aquatic macrophyte maximum colonisation depths (4 lakes) across the treated lakes. Data availability varied across the lakes and variables, and in general monitoring was more frequent closer to the application dates. Median annual TP concentrations decreased significantly across the lakes, following the La-bentonite applications (from 0.08 mg L-1 in the 24 months pre-application to 0.03 mg L-1 in the 24 months post-application), particularly in autumn (0.08 mg L-1 to 0.03 mg L-1) and winter (0.08 mg L-1 to 0.02 mg L-1). Significant decreases in SRP concentrations over annual (0.019 mg L-1 to 0.005 mg L-1), summer (0.018 mg L-1 to 0.004 mg L-1), autumn (0.019 mg L-1 to 0.005 mg L-1) and winter (0.033 mg L-1 to 0.005 mg L-1) periods were also reported. P concentrations following La-bentonite application varied across the lakes and were correlated positively with dissolved organic carbon concentrations. Relatively weak, but significant responses were reported for summer chlorophyll a concentrations and Secchi disk depths following La-bentonite applications, the 75th percentile values decreasing from 119 µg L-1 to 74 µg L-1 and increasing from 398 cm to 506 cm, respectively. Aquatic macrophyte species numbers and m
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- 2016
10. Annual review of chemical and ecological responses in Hatchmere and Mere Mere following Phoslock applications - 2013
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Spears, B.M, Gunn, I., Andrews, C., Carvalho, L., Cole, S., De Ville, M., Dudley, B., Maberly, S.C., Madgwick, G., May, L., Pitt, J., Woods, H., Winfield, I., Spears, B.M, Gunn, I., Andrews, C., Carvalho, L., Cole, S., De Ville, M., Dudley, B., Maberly, S.C., Madgwick, G., May, L., Pitt, J., Woods, H., and Winfield, I.
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- 2014
11. Studying interactions among anthropogenic stressors in freshwater ecosystems: A systematic review of 2396 multiple-stressor experiments.
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Orr JA, Macaulay SJ, Mordente A, Burgess B, Albini D, Hunn JG, Restrepo-Sulez K, Wilson R, Schechner A, Robertson AM, Lee B, Stuparyk BR, Singh D, O'Loughlin I, Piggott JJ, Zhu J, Dinh KV, Archer LC, Penk M, Vu MTT, Juvigny-Khenafou NPD, Zhang P, Sanders P, Schäfer RB, Vinebrooke RD, Hilt S, Reed T, and Jackson MC
- Subjects
- Human Activities, Stress, Physiological, Ecosystem, Fresh Water
- Abstract
Understanding the interactions among anthropogenic stressors is critical for effective conservation and management of ecosystems. Freshwater scientists have invested considerable resources in conducting factorial experiments to disentangle stressor interactions by testing their individual and combined effects. However, the diversity of stressors and systems studied has hindered previous syntheses of this body of research. To overcome this challenge, we used a novel machine learning framework to identify relevant studies from over 235,000 publications. Our synthesis resulted in a new dataset of 2396 multiple-stressor experiments in freshwater systems. By summarizing the methods used in these studies, quantifying trends in the popularity of the investigated stressors, and performing co-occurrence analysis, we produce the most comprehensive overview of this diverse field of research to date. We provide both a taxonomy grouping the 909 investigated stressors into 31 classes and an open-source and interactive version of the dataset (https://jamesaorr.shinyapps.io/freshwater-multiple-stressors/). Inspired by our results, we provide a framework to help clarify whether statistical interactions detected by factorial experiments align with stressor interactions of interest, and we outline general guidelines for the design of multiple-stressor experiments relevant to any system. We conclude by highlighting the research directions required to better understand freshwater ecosystems facing multiple stressors., (© 2024 The Author(s). Ecology Letters published by John Wiley & Sons Ltd.)
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- 2024
- Full Text
- View/download PDF
12. Lake responses following lanthanum-modified bentonite clay (Phoslock®) application: An analysis of water column lanthanum data from 16 case study lakes
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Spears, B.M., Lürling, M., Yasseri, S., Castro-Castellon, A.T., Gibbs, M., Meis, S., McDonald, C., McIntosh, J., Sleep, D., Van Oosterhout, F., Spears, B.M., Lürling, M., Yasseri, S., Castro-Castellon, A.T., Gibbs, M., Meis, S., McDonald, C., McIntosh, J., Sleep, D., and Van Oosterhout, F.
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- 2013
13. A review of progress on the monitoring of Hatchmere, Mere Mere and Alderfen Broad
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Spears, B.M., Andrews, C., Brett, H., Carvalho, L., De Ville, M., Dudley, B., Gunn, I., Kelly, A., Maberly, S.C., Madgwick, G., May, L., Pitt, J., Winfield, I., Spears, B.M., Andrews, C., Brett, H., Carvalho, L., De Ville, M., Dudley, B., Gunn, I., Kelly, A., Maberly, S.C., Madgwick, G., May, L., Pitt, J., and Winfield, I.
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- 2013
14. Role of legacy phosphorus in improving global phosphorus-use efficiency
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Condron, L.M., Spears, B.M., Haygarth, P.M., Turner, B.L., Richardson, A.E., Condron, L.M., Spears, B.M., Haygarth, P.M., Turner, B.L., and Richardson, A.E.
- Abstract
Commentary on “Tackling the phosphorus challenge: Time for reflection on three key limitations” by Ulrich et al. Environmental Development 2013 8 137-144
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- 2013
15. Water quality monitoring at Loch Leven 2008-2010: report of results
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Dudley, B.J., Spears, B.M., Carvalho, L., Gunn, I.D.M., May, L., Dudley, B.J., Spears, B.M., Carvalho, L., Gunn, I.D.M., and May, L.
- Abstract
Long-term monitoring of the water quality in Loch Leven has been undertaken by the Natural Environment Research Council since the late 1960s. Over this period, the lake has suffered serious degradation due to the combined effects of eutrophication, pesticide pollution and climate change. However, following management intervention aimed at improving the water quality of the lake, the site has undergone a slow recovery. The recovery trajectory has, at times, seemed somewhat erratic. This is due to inter-annual variations in the in-lake processes that regulate the release of legacy phosphorus from the sediments following a reduction in catchment sources, although climatic variation and changes in biological interactions have also affected the recovery in the loch. This report summarises the findings of 40 years of research on Loch Leven and presents additional data from samples collected between 2008 and 2010. The more recent data are integrated into the longer term perspective to provide an indication of whether the recovery of Loch Leven is continuing. The implications of the findings from the Loch Leven Long Term Monitoring Project, in terms of achieving water quality targets and providing key ecosystem services, are discussed.
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- 2012
16. Water quality of Loch Leven: responses to enrichment, restoration and climate change
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Carvalho, L., Miller, C., Spears, B.M., Gunn, I.D.M., Bennion, H., Kirika, A., May, L., Carvalho, L., Miller, C., Spears, B.M., Gunn, I.D.M., Bennion, H., Kirika, A., and May, L.
- Abstract
It is usually assumed that climate change will have negative impacts on water quality and hinder restoration efforts. The long-term monitoring at Loch Leven shows, however, that seasonal changes in temperature and rainfall may have positive and negative impacts on water quality. In response to reductions in external nutrient loading, there have been significant reductions in in-lake phosphorus concentrations. Annual measures of chlorophyll a have, however, shown little response to these reductions. Warmer spring temperatures appear to be having a positive effect on Daphnia densities and this may be the cause of reduced chlorophyll a concentrations in spring and an associated improvement in water clarity in May and June. The clearest climate impact was the negative relationship between summer rainfall and chlorophyll a concentrations. This is highlighted in extreme weather years, with the three wettest summers having very low chlorophyll a concentrations and the driest summers having high concentrations. To predict water quality impacts of future climate change, there is a need for more seasonal predictions from climate models and a greater recognition that water quality is the outcome of seasonal responses in different functional groups of phytoplankton and zooplankton to a range of environmental drivers.
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- 2012
17. Long-term variation and regulation of internal phosphorus loading in Loch Leven
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Spears, B.M., Carvalho, L., Perkins, R., Kirika, A., Paterson, D.M., Spears, B.M., Carvalho, L., Perkins, R., Kirika, A., and Paterson, D.M.
- Abstract
Long-term monitoring data (1968–2008) were used to investigate internal phosphorus (P) loading following external P loading reduction in shallow Loch Leven, Scotland. A whole-lake sediment P inventory (upper 3 cm of sediment; 2005) suggested a release-potential of 29.7 tonnes (t) from the release sensitive sediment P pools. 18.5 t was contained within shallow water sediments (<4.5 m water depth) with 7.6 t in deeper water sediments below the photic zone (>5 m water depth). The “observed” release (<5.1 t), estimated using a water column P mass balance approach (1989–2008), was <5.1 t, indicating the presence of regulating mechanisms. Observed P release declined between 1989 and 2008, with the exception of 2003–2006. Observed P release estimates were positively correlated with annual average water column P concentration after 1989, highlighting the role of internal loading in maintaining poor water quality conditions after management intervention. Multiple regression analysis suggested that internal loading was driven by the wave mixed depth in spring (positive driver), summer water temperature (positive driver) and spring water clarity transparency (negative driver). The potential importance of biological and physico-chemical feedback mechanisms in the regulation of benthic–pelagic coupling and water quality in Loch Leven are discussed.
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- 2012
18. Long-term variations in waterfowl populations in Loch Leven: identifying discontinuities between local and national trends
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Carss, D., Spears, B.M., Quinn, L., Cooper, R., Carss, D., Spears, B.M., Quinn, L., and Cooper, R.
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Loch Leven has been designated as a UK Ramsar Site (1976), a Site of Special Scientific Interest (1985) and a Special Protection Area (2000) due to its importance as a site for overwintering waterfowl. However, no comprehensive assessment of trends in waterfowl at the local versus national scale has been conducted at the site. Coherence between trends in 5-year mean species abundance for Loch Leven and Underhill Indexing Method values for Scotland (or GB in the case of geese) were assessed using principal components analysis for ten study species between 1968 and 2006. Five species showed trends at Loch Leven that were coherent with those at the Scottish scale (Eurasian Teal, Mute Swan, Great Cormorant, Pink-footed and Greylag geese). These species may not respond positively to local scale management. However, the other five species (Mallard, Coot, Great Crested Grebe, Tufted Duck and Pochard) showed distinct differences between local and national trends. A study of the feeding ecology for these species, the re-establishment of ringing effort and an assessment of waterfowl–wetland relationships are recommended to determine how changes in local food resources and habitat quality interact with macro-scale population dynamics to influence local and regional patterns of abundance.
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- 2012
19. A history of scientific research at Loch Leven, Kinross, Scotland
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May, L., Spears, B.M., May, L., and Spears, B.M.
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Loch Leven is a large, shallow lake in lowland Scotland, UK. Scientific research began here almost 200 years ago. Early research characterised the biodiversity and physical characteristics of the loch, providing an important historical background for future research. In the mid-1960s, this ad hoc approach was superseded by a more structured research programme under the umbrella of the International Biological Programme. This was the beginning of the Loch Leven long-term monitoring programme. Today, the results of these studies form one of the longest and most comprehensive limnological datasets for shallow freshwater lakes in the world, comprising more than 500 physical, chemical and biological variables collected at two-weekly intervals. To celebrate the 40th anniversary of the start of the long term monitoring programme, and to highlight the scientific investigations still being conducted at Loch Leven, the NERC Centre for Ecology & Hydrology (CEH) organised a symposium entitled “Loch Leven: 40 years of scientific research” in Kinross, Scotland, UK, on 11 December 2008. This examined the role of long-term monitoring in developing our understanding of the links between pollution, climate change and ecological responses in shallow lakes. This article introduces a series of papers summarising the scientific results presented at this meeting.
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- 2012
20. Managing ecosystem services at Loch Leven, Scotland, UK: actions, impacts and unintended consequences
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May, L., Spears, B.M., May, L., and Spears, B.M.
- Abstract
Rivers, lakes and wetlands are good examples of ecosystems that provide multiple, concurrent, services to mankind. Human society has often exploited these systems by enhancing one ecosystem service at the expense of another. Loch Leven, Scotland, UK, is a good example of this. Over the past 150 years, the lake has been subjected to hydrological modification, fish stocking and pollution control to improve the delivery of key goods and services. This study uses historical records to explore the results of these interventions on the ecosystem services that were targeted for improvement and the knock-on effects on other services provided by the lake. The results suggest that, when management changes are being considered to enhance particular ecosystem services, the potentially damaging effects on other ecosystem services should be taken into account. This requires a better understanding of the role of ecosystem function in delivering ecosystem services, and of the links between multiple ecosystem services, than is currently available. While further research is clearly needed, the value of long term datasets in providing knowledge and understanding through ‘hindsight’ should not be underestimated. The study concludes that successful management actions are likely to be those that incorporate lessons learned from previous decisions.
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- 2012
21. The contribution of epipelon to total sediment microalgae in a shallow temperate eutrophic loch (Loch Leven, Scotland)
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Spears, B.M., Carvalho, L., Perkins, R., O'Malley, M.B., Paterson, D.M., Spears, B.M., Carvalho, L., Perkins, R., O'Malley, M.B., and Paterson, D.M.
- Abstract
Benthic microalgae are known to perform important ecosystem functions in shallow lakes. As such it is important to understand the environmental variables responsible for regulating community structure, positioning and biomass. We tested the hypothesis that the positioning (across a depth gradient of 2 – 22 m overlying water depth) and relative biomass (determined using bulk and lens tissue harvested chlorophyll (Chl) a concentrations) of the epipelon community would vary independently with season (12 monthly samples) and across natural gradients of light and habitat disturbance relative to the total benthic algal community (i.e. all viable microalgae in the surface sediments) in a shallow eutrophic lake. Total sediment microalgal Chl a concentrations (TS-Chl; range: 5 to 874 µg Chl a g-1dw) were highest in winter and in the deepest site (20 m overlying water depth), apparently as a result of phytoplanktonic settling and sediment focussing processes. Epipelic Chl a concentrations (Epi-Chl; range: < 0.10 to 6.0 µg Chl a g-1dw) were highest in winter/spring, a period when water clarity was highest and TS-Chl lowest. Principal components analysis highlighted strong associations between Epi-Chl and sites of intermediate depths (2.5 m to 5.5 m) in all seasons except autumn/winter. Autumn/winter represented the season with the highest average wind speeds preceding sampling, during which the highest Epi-Chl concentrations were associated with the deepest sites. Epi-Chl was associated with intermediate light and habitat disturbance during spring/summer and summer/autumn and varied positively with habitat disturbance, only, in autumn/winter and winter/spring. The epipelon community structure also varied with depth; diatoms dominated shallow water sediments, cyanobacteria dominated deep water sediments, and sediments at sites of intermediate depth returned the highest biovolume estimates and the most diverse communities. This study has strengthened the hypothesis that the stru
- Published
- 2010
22. Nutrient modelling and a nutrient budget for Llangorse Lake Final Report
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May, L., Dudley, B., Spears, B.M., Hatton-Ellis, T.W., May, L., Dudley, B., Spears, B.M., and Hatton-Ellis, T.W.
- Abstract
Llangorse Lake is the largest natural lake in South Wales. There have been concerns about eutrophication problems here for many years. The problem is believed to have been caused by high nutrient loads entering the lake from the surrounding catchment. This study aimed to determine the size and main sources of those loads. The phosphorus (P) and nitrate (NO3-N) load to Llangorse Lake was found to be approximately 2 tonnes P y 1 and 74 tonnes NO3-N y 1 (which is equivalent to 1.5 g P m-2 y-1 and 53 g NO3 N m-2 y-1). Most of the P and NO3-N loads were found to be entering the lake from only two of the inflow streams (i.e. those draining to Sites 2 and 6). These accounted for 85 per cent of the annual P load and 82 per cent of the annual NO3-N load to the lake. The hydrology of the Llangorse catchment appears to be strongly affected by groundwater. This is best demonstrated at Site 6, where the surface water catchment upstream of the site accounts for only 36 per cent of the lake catchment but contributes 67 per cent of annual hydraulic load. This, and the fact that the flow at Site 6 is almost double that which can be accounted for by rainfall, suggests that there is considerable groundwater flow in this area. If the streams that flow into the lake have significant input from groundwater, this will affect their hydrology and chemistry. As this groundwater may enter the drainage system from an area beyond the boundary of the surface water catchment, this has serious implications for catchment management aimed at reducing the nutrient loads to the lake. Some of the inflow streams showed evidence of occasional point source pollution in very wet weather. This suggests that there is a need, in some places at least, to control point sources of pollution that leak or overflow during heavy rainfall. However, the evidence suggests that most sources of nutrients within the catchment are diffuse sources. Most of the published literature concerning the eutrophication and recovery
- Published
- 2008
23. The ecology of freshwater epipelic algae: an update
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Poulickova, Aloisie, Hasler, Petr, Lysakova, Monika, Spears, B.M., Poulickova, Aloisie, Hasler, Petr, Lysakova, Monika, and Spears, B.M.
- Abstract
Epipelic algae perform a range of ecosystem functions including biostabilisation of sediments, regulation of benthic–pelagic nutrient cycling, and primary production. There is a growing need to understand their ecological role in light of current and future alterations in sediment loading resulting from land-use change and land management practices. Although the majority of recent work on epipelic algal ecology has been conducted within estuarine ecosystems, significant advances have also been made in freshwaters. We review these recent studies in combination with more classical freshwater approaches to highlight the importance of freshwater epipelic algal ecology and to aid discussions regarding future research. A summary of benthic algal groups is given with particular emphasis on substratum preference and habitat boundaries. No standard methodology exists for sampling freshwater epipelon, and we discuss the advantages and disadvantages of a suite of currently employed methodologies. Spatial variability in epipelic community biodiversity is discussed from the micro-scale (i.e. vertical migration in the sediment surface) to the ecosystem scale (i.e. lake vs river habitats), and finally at the geographic scale (i.e. the ‘ubiquity’ of epipelic species). Factors regulating epipelon community composition and biomass (e.g. reproductive strategies, habitat disturbance, grazing pressures, resource limitation, resilience, symbiosis, and parasitism) are also reviewed. Finally, examples of specific epipelic ecosystem functions (e.g. primary production, biostabilisation, and regulation of biogeochemical cycling) are given and areas of research requiring particular focus in the future are outlined.
- Published
- 2008
24. Role of legacy phosphorus in improving global phosphorus-use efficiency
- Author
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Condron, L.M., primary, Spears, B.M., additional, Haygarth, P.M., additional, Turner, B.L., additional, and Richardson, A.E., additional
- Published
- 2013
- Full Text
- View/download PDF
25. Changes in the Buffer Properties of the Restored Lake Complex.
- Author
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Grochowska, Jolanta Katarzyna, Goździejewska, Anna Maria, and Augustyniak-Tunowska, Renata
- Abstract
The objects of this study were lakes Mielenko (LM) (7.8 ha, 1.9 m), Klasztorne Małe (LKM) (13.7 ha, 20.0 m), and Klasztorne Duże (LKD) (57.5 ha, 8.5 m), located in north Poland (Kashubian Lake District). These lakes received raw sanitary and storm wastewater, leading to extreme degradation of these water bodies. This study aimed to present changes in buffer indicators such as reaction, alkalinity, total hardness, and Ca and Mg content that occurred as an effect of their restoration using the sequential application of coagulants as an innovative approach to the phosphorus inactivation method. Sustainable phosphorus inactivation in the study lakes made it possible to achieve nutrient concentrations in the range of values typical for low-trophic lakes. A radical decrease in P concentration in the water resulted in a limitation of production processes. Moreover, after a, it was noticed that the water parameters determining its buffering properties did not show a clear vertical stratification with increasing values toward the bottom. For example, before restoration, the mean e value of alkalinity in LM fluctuated around 2.10 mval/L, and after restoration activities, the average value was 1.97 mval/L. In LKM, the mean alkalinity value in surface water layers was 2.53 mval/L, and in bottom water layers, it was 4.92 mval/L; after restoration treatments, the average alkalinity of surface water was 2.18 mval/L, and in bottom water, it was 2.99 mval/L. In the last LKD, under the influence of the applied restoration, the average alkalinity of surface waters changed from 2.21 to 2.07 mval/L, and in bottom water, it changed from 2.86 to 2.12 mval/L. The values of parameters determining the buffering properties of lake water after restoration activities allow their water to be classified as slightly or medium hard. The changes obtained can be considered beneficial because water that is too hard does not support the development of aquatic organisms, and the values obtained in the study lakes after sustainable restoration are optimal for the construction of plant walls, shells, and fish bones. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
26. Identifying Determinants of Spatiotemporal Disparities in Ecological Quality of Mongolian Plateau.
- Author
-
Wang, Zhengtong, Song, Yongze, Zhang, Zehua, Lin, Gang, Luo, Peng, Zhang, Xueyuan, and Chai, Zhengyuan
- Subjects
NORMALIZED difference vegetation index ,REMOTE sensing ,ENVIRONMENTAL health ,VEGETATION dynamics ,ENVIRONMENTAL quality - Abstract
Vegetation quality is crucial for maintaining ecological health, and remote sensing techniques offer precise assessments of vegetation's environmental quality. Although existing indicators and remote sensing approaches provide extensive spatial coverage, challenges remain in effectively integrating diverse indicators for a comprehensive evaluation. This study introduces a comprehensive ecological quality index (EQI) to assess vegetation quality on the Mongolian Plateau from 2001 to 2020 and to identify the determinants of EQI variations over space and time. We developed the EQI using remotely sensed normalized difference vegetation index (NDVI) data and the net primary productivity (NPP). Our analysis revealed distinct spatial patterns, with high ecological quality concentrated in northern Mongolia and eastern Inner Mongolia. Temporal fluctuations, indicative of ecological shifts, were primarily observed in eastern Mongolia and specific zones of Inner Mongolia. We employed a Geographically Optimal Zones-based Heterogeneity (GOZH) model to analyze the spatial scales and interactions influencing EQI patterns. This study found that precipitation, with an Omega value of 0.770, was the dominant factor affecting the EQI, particularly at spatial scales of 40–50 km. The GOZH model provided deeper insights into the spatial determinants of the EQI compared with previous models, highlighting the importance of climatic variables and their interactions in driving ecological quality. This research enhanced our understanding of vegetation quality dynamics and established a foundation for ecosystem conservation and informed management strategies, emphasizing the critical role of climate, especially precipitation, in shaping ecological landscapes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Phosphate Solubilization and Plant Growth Promotion by Enterobacter sp. Isolate.
- Author
-
Damo, Jean Louise Cocson, Pedro, Mannix, and Sison, Maria Lourdes
- Subjects
PLANT growth-promoting rhizobacteria ,ALTERNATIVE agriculture ,ALUMINUM phosphate ,MICROBIAL inoculants ,GLUCONIC acid - Abstract
Phosphorus (P) solubilization is one of the major traits for plant growth-promoting rhizobacteria since P is easily rendered insoluble in soil. Phosphate-solubilizing microorganisms can be harnessed as an environment-friendly strategy to enhance the mobilization and acquisition of P by crops. Utilization of such microorganisms as microbial inoculants in agriculture serves as an alternative to chemical fertilizers and an approach for more efficient P fertilization. Hence, this study aims to characterize a phosphate-solubilizing isolate and evaluate its potential as a microbial inoculant. Morphological, biochemical, and genetic characterization of the isolate were performed. Then, the mineral phosphate solubilization ability of the isolate was evaluated. Lastly, this study evaluated the plant growth promotion of the isolate as a single inoculant in rice or as a co-inoculant with rhizobia in peanuts. On the basis of biochemical and 16S rRNA analysis, the isolate was identified as Enterobacter sp. Also, it can solubilize P from tricalcium phosphate or aluminum phosphate. Simultaneous with P solubilization, medium acidification, and gluconic acid secretion were observed. Lastly, the Enterobacter sp. isolate could potentially be developed as a biofertilizer in reducing P resource input or to enhance the performance of a rhizobia inoculant. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. Evaluation of Water Quality and Pollution Source Analysis of Meihu Reservoir.
- Author
-
Qi, Yiting, Li, Cong, Zhang, Kai, Sumita, Li, Jun, He, Zhengming, Cao, Xin, and Yan, Ailan
- Subjects
WATER pollution ,DRINKING water quality ,AGRICULTURAL pollution ,WATER quality ,DRINKING water standards ,WATER quality monitoring - Abstract
Under the background of increasingly serious global environmental pollution, ensuring the safety of drinking water has become one of the focuses of global attention. In this study, Meihu Reservoir, a drinking water source, was selected as the research object, and the main pollution problems and their sources were revealed through conventional water quality analysis, suitability evaluation of the drinking water source and eutrophication evaluation of the reservoir. Using modern water quality monitoring technology and methods, the paper monitors and analyzes various water quality parameters of the Meihu Reservoir. The results showed that the water quality indexes, except total nitrogen, met the class II–III standard of drinking water, and the comprehensive nutrient state index method (TLI) evaluated the reservoir, and its index met 30 ≤ TLI (∑) ≤ 50 , indicating that the reservoir belongs to the medium nutrition category. Therefore, the water quality of the reservoir has been affected by different degrees of agricultural, domestic and livestock pollution, mainly reflected in the serious excess of the total nitrogen index (the peak has reached 2.99 mg/L). The results of the on-site investigation showed that the main sources of nitrogen in the reservoir included agricultural non-point-source pollution, domestic sewage pollution, domestic garbage pollution and livestock and poultry pollution, accounting for 50.09%, 23.99%, 14.13% and 11.80% of the total load, respectively. On this basis, this paper puts forward some countermeasures for pollution control in order to provide a scientific basis and practical path for water quality protection and improvement of the Meihu Reservoir and other similar reservoirs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. Phosphorous Utilization in Microalgae: Physiological Aspects and Applied Implications.
- Author
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Bossa, Rosanna, Di Colandrea, Melania, Salbitani, Giovanna, and Carfagna, Simona
- Subjects
ECOPHYSIOLOGY ,ENVIRONMENTAL remediation ,PLANT metabolism ,PHOSPHORUS compounds ,BIOTECHNOLOGY - Abstract
Phosphorus (P) is a fundamental element for life, playing an integral role in cellular metabolism including energy transfer, nucleic acid synthesis, and membrane structure. This nutrient is critical to the physiological ecology in all photosynthetic organisms including eukaryotic microalgae and cyanobacteria. The review, here presented, delves into the intricate mechanisms governing phosphorus acquisition from the environment, its utilization in plant metabolism, and regulation in these photosynthetic microorganisms. Furthermore, it comprehensively explores the strategies employed by microalgae to cope with phosphorus limitation, such as the activation of high-affinity phosphate transporters and the synthesis of phosphorus storage compounds. On the other hand, the ability to consume abundant phosphate makes microalgae exploitable organisms for environmental remediation processes. The knowledge synthesized in this review contributes to the broader understanding of microalgal physiology, offering insights into the ecological and biotechnological implications of phosphorus assimilation in these microorganisms. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. Developing Macroinvertebrate Biotic Indices in Nigerian Urban-Agricultural River Catchments: Is the Continuous Scoring System More Effective than Discrete Scoring System?
- Author
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Edegbene, Augustine Ovie, Arimoro, Francis Ofurum, and Odume, Oghenekaro Nelson
- Subjects
ENVIRONMENTAL health ,AGRICULTURAL pollution ,DISCRETE systems ,WATERSHEDS ,URBAN agriculture - Abstract
The evaluation of the ecological consequences of anthropogenic stressors is a critical challenge in the management of the environment. Multimetric indices (MMIs) are one of the biomonitoring tools that have been widely explored to assess the ecological health of riverine systems globally, as MMIs have proven to be extremely effective, owing to their ability to incorporate data and information from both structural and functional assemblages of organisms and the entire ecosystem. Currently, there are very few MMIs developed in Nigeria to assess the ecological health of riverine systems, and none of the MMIs was developed for river stations draining urban and agricultural catchments. In order to close this gap, we developed and validated a macroinvertebrate-based MMI for assessing the ecological health of river systems in the Niger Delta area of Nigeria draining urban and agriculture catchments. Furthermore, we also compared the effectiveness of both continuous scoring and discrete systems for the development of MMI. Physico-chemical variables and macroinvertebrates were collected from 17 well-marked out stations that spread throughout 11 different river systems. The stations were classified into three categories based on the degree of impact: least-impacted stations (LIS), moderately impacted stations (MIS), and heavily impacted stations (HIS). Sixty-seven (67) candidate macroinvertebrate metrics were potentially tested, and only five metrics were deemed significant and ultimately retained for integration into the final Niger Delta urban–agriculture MMI. The following five metrics were chosen to remain in use for the MMI development: Chironomidae/Diptera abundance, %Odonata, Margalef index, Oligochaete richness and logarithmic-transformed relative abundance of sprawler. Notable performance rates of 83.3% for the least-impacted stations and 75% for the moderately impacted stations were found during the index's validation using a different dataset. However, for the stations that were most affected (i.e., the HIS), a 22.2% performance rate was noted. The Niger Delta urban–agriculture MMI was adjudged to be suitable as a biomonitoring tool for riverine systems subjected to similar combined stressors of urban and agricultural pollution. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Mathematical Modeling of Oxygen Transfer Using a Bubble Generator at a High Reynolds Number: A Partial Differential Equation Approach for Air-to-Water Transfer.
- Author
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Constantin, Mihaela, Dobre, Cătălina, and Oprea, Mugurel
- Subjects
REYNOLDS number ,PARTIAL differential equations ,ENVIRONMENTAL engineering ,BODIES of water ,DIFFERENTIAL equations - Abstract
This paper presents the mathematical modeling of the oxygen transfer process using partial differential equations (PDEs). This process is crucial in various environmental and engineering applications, such as wastewater treatment, aeration systems, and natural water bodies, in order to maintain water quality. The authors solved the typical PDE for describing the change in oxygen concentration over time and present the developed model of the differential equation with the term "source", indicating that the model could be used to optimize oxygen transfer in various environmental and engineering applications, contributing to improved water quality and system efficiency. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. Scenario Analysis of Food Phosphorus Footprint in Kisumu, a Lakeside East African City in Lake Victoria (Kenya).
- Author
-
Guo, Zheng, Chen, Sophia Shuang, Kattel, Giri Raj, Qiao, Wenyi, Lu, Linglong, Li, Rong, and Mkumbo, Anna Charles
- Subjects
DIETARY patterns ,SEPTIC tanks ,CITIES & towns ,WASTE management ,FOOD chemistry ,FOOTPRINTS - Abstract
Increased food production and consumption patterns have resulted in higher urban food phosphorus footprints, leading to a series of resource and environmental problems worldwide. We quantified the food phosphorus footprint of the African city of Kisumu using substance flow analysis. Our aim was to develop Kisumu's sustainable phosphorus management framework so that the city would reduce phosphorus losses into the food system. Our results show that in the year 2023, the import and export of food phosphorus in the Kisumu food system was 2730.26 ± 2.7% t P yr
−1 and 3297.05 ± 2.4% t P yr−1 , respectively. There was −566.79 ± −18% t P yr−1 food phosphorus deficit in the Kisumu food system. Crop planting subsystem runoff/leaching/erosion loss, household consumption subsystem waste loss, and pit latrine subsystem blackwater loss are the major pathways of phosphorus losses into the environment and the main contributors to the food phosphorus footprint in the city. The 2030 scenario analysis shows that implementing a comprehensive scenario scheme throughout the entire lifecycle process from phosphorus input to waste disposal is the best choice for reducing phosphorus losses and suppressing the growth of food phosphorus footprint in the future. Our study shows that the food phosphorus footprint in the Kisumu food system was 0.67 kg P cap−1 yr−1 in 2023, which is still at a low level but may enter a continuous upward trend with the improvement of socio-economic development of the city. In our framework, we have proposed a few essential measures that include urine separation, installation of septic tank, adjustment of dietary structure, flexible layout of sanitary disposal facilities, and separation of organic waste streams to reduce food phosphorus footprints in Kisumu. Given the similarity of cities along the shores of Lake Victoria, our calculation methods and management strategies can be applied to other cities in the region. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
33. Characterization of Low-Molecular-Weight Dissolved Organic Matter Using Optional Dialysis and Orbitrap Mass Spectrometry.
- Author
-
Li, Qiuxing, Zhang, Runyu, Huang, Guopei, Yuan, Haijun, Wang, Liying, and Xu, Shuxia
- Subjects
MEMBRANE separation ,MASS spectrometry ,FULVIC acids ,ORGANIC compounds ,MOLECULAR weights - Abstract
Low-molecular-weight (LMW, <1000 Da) dissolved organic matter (DOM) plays a significant role in metal/organic pollutant complexation, as well as photochemical/microbiological processes in freshwater ecosystems. The micro size and high reactivity of LMW-DOM hinder its precise characterization. In this study, Suwannee River fulvic acid (SRFA), a commonly used reference material for aquatic DOM, was applied to examine the optical features and molecular composition of LMW-DOM by combining membrane separation, ultraviolet–visible absorption and Orbitrap mass spectrometry (MS) characterization. The 100–500 Da molecular weight cut-off (MWCO) membrane had a better performance in regard to separating the tested LMW-DOM relative to the 500–1000 Da MWCO membrane. The ultraviolet–visible absorbance decreased dramatically for the retentates, whereas it increased for the dialysates. Specifically, carbohydrates, lipids and peptides exhibited high selectivity to the 100–500 Da MWCO membrane in early dialysis. Lignins, tannins and condensed aromatic molecules displayed high permeability to the 500–1000 Da MWCO membrane in late dialysis. Overall, the retentates were dominated by aromatic rings and phenolic hydroxyls with high O/C
wa (weighted average of O/C) and low H/Cwa . Conversely, such dialysates had numerous aliphatic chains with high H/Cwa and low O/Cwa compared to SRFA. In particular, LMW-DOM below 200 Da was identified by Orbitrap MS. This work provides an operational program for identifying LMW-DOM based on the SRFA standard and MS analysis. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
34. Drivers of Plant Invasion in Stream Restoration.
- Author
-
DeBerry, Douglas A. and Hunter, Dakota M.
- Subjects
PLANT invasions ,STREAM restoration ,JAPANESE honeysuckle ,RIPARIAN areas ,RIPARIAN forests ,SOIL texture ,INVASIVE plants - Abstract
This study characterized important environmental factors that contribute to plant invasion in the forested riparian zones surrounding stream restoration sites. We sampled vegetation and environmental variables (light availability, soil physiochemistry, and site age) across invasion gradients at multiple sites in Virginia, USA. Data analysis involved a multimetric statistical approach combining correlation and Canonical Correspondence Analysis (CCA) to arrive at a plausible model for invasion risk by species. We targeted three of the most problematic invaders in these systems: Lespedeza cuneata (sericea lespedeza), Lonicera japonica (Japanese honeysuckle), and Microstegium vimineum (Japanese stiltgrass). Our analysis revealed species-specific environmental drivers of invasion, with certain factors consistently important across all targeted invaders—notably, canopy cover, nitrogen availability, soil texture, and bioavailable phosphorus, as indicated by the importance of certain proxies (e.g., metal cations). The results of this research have been used to develop a suite of best practices that can be implemented at the outset of a stream restoration project to reduce the risk of invasion in the riparian forests surrounding these sites. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. The Evolutionary System of the Biosphere and the Metameric Concept of Its Evolution: From the Past to the Future.
- Author
-
Protasov, Alexander and Barinova, Sophia
- Subjects
BIOSPHERE ,ANTHROPOGENIC effects on nature - Abstract
We offer a detailed description of our previously published new concept of the evolution of the biosphere as an integral system of its states over time, united by development trends. The structure of the biosphere is considered as a hierarchical fractal system, and the elementary unit of the biosphere is an ecosystem. The fractal structure of the biosphere corresponds to the emergent principle: each lower level is an element of a more complex system and has its own properties. The proposed concept of biosphere evolution is based on the general categories of dialectics: states and interstates, continuity and discreteness, reproducibility and uniqueness. The evolutionary history of the biosphere is a metameric picture of changing states and interstates. The most important feature of the biosphere organization in space–time is a complex system of continua. The development of an integral biospheric system occurs in a time continuum: in the biosphere, the differences between the early and subsequent states are quite significant and obvious. Moreover, these differences are associated with fundamental complications, development, which is, in fact, evolution. The states of the biosphere in certain periods are linked by trends that form an evolutionary system. Continuing states, when the system remains self-identical for a long period, are replaced by new states through interstates. Based on the principle of actualism, the problems of the biosphere's future and evolutionary trends of the biosphere under anthropogenic impact are considered. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Dual Effect of Microplastics and Cadmium on Stream Litter Decomposition and Invertebrate Feeding Behavior.
- Author
-
He, Hualong, Cai, Sulin, Chen, Siyuan, Li, Qiang, Luo, Yunchao, Zeng, Xiaoyi, Ye, Rumeng, Wan, Pengwei, and Tian, Xingjun
- Subjects
MICROPLASTICS ,FOREST litter ,FUNGAL communities ,CADMIUM ,LITTER (Trash) ,NUTRIENT cycles ,MICROPOLLUTANTS ,MARINE invertebrates ,WOOD-decaying fungi - Abstract
This study investigates the combined effect of microplastics and cadmium on the decomposition of litter, the structure of fungal communities, and the feeding behavior of invertebrates in an aquatic ecosystem. Through a series of microcosm experiments, we demonstrate that exposure to MPs and Cd significantly reduced the decomposition of leaf litter. Notably, the cumulative impact of combined MP and Cd exposure was found to be greater than their individual effects. During this process, the carbon–nitrogen ratio of the litter increased, while dehydrogenase activity and fungal biomass were inhibited. Additionally, the relative abundance of Ascomycota and Basidiomycota fungi decreased, weakening their role in the decomposition of leaf litter. Conversely, MPs and Cd reduced the relative content of leaf litter lignin, improving its quality as food, thereby leading to an increase in the feeding rate of invertebrates. This dual effect indicates that micropollutants suppress the decomposition of litter by regulating microbial metabolic activity and fungal community structure but promote invertebrate feeding. Our findings provide crucial insights into the adverse effects of MPs and Cd on the structure and diversity of aquatic fungal communities, which could have long-term impacts on the food webs and nutrient cycling progress of aquatic ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
37. The Effect of Renewable Phosphorus Biofertilizers on Selected Wheat Grain Quality Parameters.
- Author
-
Jastrzębska, Magdalena, Kostrzewska, Marta K., and Saeid, Agnieszka
- Subjects
SEWAGE sludge ash ,PHOSPHATE fertilizers ,THIOBACILLUS ferrooxidans ,WHEAT ,ENVIRONMENTAL security ,BIOFERTILIZERS ,GRAIN ,WINTER wheat - Abstract
Recycling and reusing phosphorus in agriculture can reduce the consumption of natural phosphorus resources, which are continuing to shrink. Phosphorus fertilizers made from renewable raw materials (sewage sludge ash, animal bones, dried animal blood) and activated with phosphorus solubilizing microorganisms (Bacillus megaterium, Acidithiobacillus ferrooxidans) offer an alternative to conventional fertilizers. These products should meet consumer and environmental safety standards. In this paper, based on field experiments conducted in northeast Poland, the effects of waste-derived biofertilizers on selected parameters of wheat yield quality are discussed. The study focuses on the technological properties of the grain (hectoliter weight, hardness index, Zeleny index, starch, wet gluten, and protein content), the content of proteogenic amino acids, macro- and micronutrients, and selected toxic elements in the grain. The quality parameters of wheat grain were not affected by the tested biofertilizers applied in P doses up to 35.2 kg ha
−1 , nor by conventional fertilizers. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
38. An Integrated and Multi-Stakeholder Approach for Sustainable Phosphorus Management in Agriculture.
- Author
-
Colombo, Federico, Pesenti, Michele, Araniti, Fabrizio, Pilu, Salvatore Roberto, and Nocito, Fabio Francesco
- Subjects
RUSSIAN invasion of Ukraine, 2022- ,PHOSPHATE rock ,FRESHWATER biodiversity ,PRICES ,PHOSPHATE fertilizers - Abstract
Conventional agriculture relies on non-renewable rock phosphate as a source of phosphorus. The demand for food has led to increased phosphorus inputs, with a negative impact on freshwater biodiversity and food security. The importation of phosphorus fertilizers makes most food systems vulnerable to phosphorus supply risks. The geopolitical instability generated by the pandemic and the current Russia–Ukraine conflict, which has led to a 400% increase in phosphorus commodity prices, offers the international community and institutions an opportunity to embrace the global phosphorus challenge and move towards a more circular system. Here, we discuss an integrated and multi-stakeholder approach to improve phosphorus management in agriculture and increase the efficiency of the whole chain, highlighting the contribution of conventional breeding and genetic engineering, with a particular focus on low-phytic-acid (lpa) crops, whose grains may help in reducing phosphorus-management-related problems. In recent decades, the choice of short-term strategies—such as the use of phytase as a feed additive—rather than lpa mutants, has been carried out without considering the long-term money saving to be derived from lpa crops. Overall, lpa crops have the potential to increase the nutritional quality of foods and feeds, but more research is needed to optimize their performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. Introduction of Native Submerged Macrophytes to Restore Biodiversity in Streams.
- Author
-
Van der Cruysse, Lucas, De Cock, Andrée, Lock, Koen, Boets, Pieter, and Goethals, Peter L. M.
- Subjects
POTAMOGETON ,MACROPHYTES ,RESTORATION ecology ,STREAM restoration ,ENDANGERED ecosystems ,BIODIVERSITY ,HABITAT destruction ,WATER pollution - Abstract
Streams are biodiversity hotspots that provide numerous ecosystem services. Safeguarding this biodiversity is crucial to uphold sustainable ecosystem functioning and to ensure the continuation of these ecosystem services in the future. However, in recent decades, streams have witnessed a disproportionate decline in biodiversity compared to other ecosystems, and are currently considered among the most threatened ecosystems worldwide. This is the result of the combined effect of a multitude of stressors. For freshwater systems in general, these have been classified into five main pressures: water pollution, overexploitation, habitat degradation and destruction, alien invasive species, and hydromorphological pressures. On top of these direct stressors, the effects of global processes like environmental and climate change must be considered. The intricate and interconnected nature of various stressors affecting streams has made it challenging to formulate effective policies and management strategies. As a result, restoration efforts have not always been successful in creating a large-scale shift towards a better ecological status. In order to achieve an improved status in these systems, situation-specific management strategies tailored to specific stressor combinations may be needed. In this paper, we examine the potential of introducing native submerged macrophyte species to advance the restoration of stream ecosystems. Through successful introductions, we anticipate positive ecological outcomes, including enhanced water quality and increased biodiversity. This research is significant, as the potential success in restoring stream biodiversity not only represents progress in ecological understanding but also offers valuable insights for future restoration and management strategies for these vital ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. Microbial Diversity Impacts Non-Protein Amino Acid Production in Cyanobacterial Bloom Cultures Collected from Lake Winnipeg.
- Author
-
Bishop, Stephanie L., Solonenka, Julia T., Giebelhaus, Ryland T., Bakker, David T. R., Li, Isaac T. S., and Murch, Susan J.
- Subjects
CYANOBACTERIAL blooms ,MICROBIAL diversity ,LIQUID chromatography-mass spectrometry ,AMINO acids ,MICROCYSTIS ,ALGAL blooms - Abstract
Lake Winnipeg in Manitoba, Canada is heavily impacted by harmful algal blooms that contain non-protein amino acids (NPAAs) produced by cyanobacteria: N-(2-aminoethyl)glycine (AEG), β-aminomethyl-L-alanine (BAMA), β-N-methylamino-L-alanine (BMAA), and 2,4-diaminobutyric acid (DAB). Our objective was to investigate the impact of microbial diversity on NPAA production by cyanobacteria using semi-purified crude cyanobacterial cultures established from field samples collected by the Lake Winnipeg Research Consortium between 2016 and 2021. NPAAs were detected and quantified by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) using validated analytical methods, while Shannon and Simpson alpha diversity scores were determined from 16S rRNA metagenomic sequences. Alpha diversity in isolate cultures was significantly decreased compared to crude cyanobacterial cultures (p < 0.001), indicating successful semi-purification. BMAA and AEG concentrations were higher in crude compared to isolate cultures (p < 0.0001), and AEG concentrations were correlated to the alpha diversity in cultures (r = 0.554; p < 0.0001). BAMA concentrations were increased in isolate cultures (p < 0.05), while DAB concentrations were similar in crude and isolate cultures. These results demonstrate that microbial community complexity impacts NPAA production by cyanobacteria and related organisms. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. Combining Multiple Remediation Techniques Is Effective for the Remediation of Eutrophic Flowing Water.
- Author
-
Luo, Ran, Li, Wei, Zhong, Jiayou, Dai, Taotao, Liu, Jinfu, Zhang, Xiaoliang, Chen, Yuwei, and Gao, Guiqing
- Subjects
PHOSPHORUS in water ,NITROGEN in water ,RESTORATION ecology ,DREDGING ,PHYTOREMEDIATION ,PLANT species ,EUTROPHICATION - Abstract
Dredging, adsorbent inactivation, and phytoremediation are commonly used to control internal nitrogen and phosphorus sediment loads in eutrophic still-water ecosystems, such as lakes and ponds. However, the effectiveness of these remediation techniques has not been verified for rivers, lakes, and reservoirs with large disturbances. In this study, a calcium-loaded clay granular adsorbent (CRB) was prepared as an alternative to commercial adsorbents, and an experiment was conducted on the ecological restoration effects of both dredging and adsorbent single treatments as well as combined treatments on eutrophic flowing water. The enhancement effect of phytoremediation on the above restoration techniques was investigated. The results indicated that CRB inactivation treatment reduced the phosphorus and turbidity of the water by 63% and 80%, respectively and increased the total nitrogen and permanganate index (COD
Mn ) by 25% and 101% before phytoremediation, respectively compared to the control group. There were no significant differences in the nutrient indexes of the sediment and water between the dredging treatment and the control group, but dredging enhanced the effect of the CRB treatment. Compared with the CRB treatment, the total nitrogen and CODMn of water in the dredging and combined CRB treatments decreased by 13% and 15%, respectively. Phytoremediation significantly improved the effectiveness of the dredging and adsorbent treatments, both individually and in combination. Additionally, there were notable differences in the growth rates of the submerged plants and the contents of different phosphorus speciation among the plant species. Selecting suitable plant species is recommended when implementing phytoremediation methods. This study highlights that the combination of multiple restoration techniques is effective for eutrophic flowing water. The results provide a guide for the ecological restoration of flowing water. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
42. Effect of Combined Application of Lanthanum-Based Capping Material and Biochemical Oxidant on Control of Internal Phosphorus.
- Author
-
Liu, Yvlu, Geng, Bing, Wu, Guoyi, Si, Jingyi, Liu, Yi, Ning, Dongliang, and Lin, Juan
- Subjects
SEDIMENT control ,OXIDIZING agents ,PHOSPHORUS ,CALCIUM nitrate ,FULLER'S earth - Abstract
In situ capping and biochemical oxidation are two of the most commonly used methods for internal phosphorus (P) control, but there are few studies on the combined use of these two methods. In this study, two lanthanum (La)-based materials, La-modified bentonite (LMB) and the La-modified attapulgite and chitosan composite (LMA&C), were combined with calcium nitrate (CN) to investigate the effect on sediment P control. Results showed that SRP removal rates by LMB+CN and LMA&C+CN were much higher than that by LMB, LMA&C and CN alone. LMB+CN and LMA&C+CN decreased DGT-labile P flux both in overlying water and surface 65 mm sediment, while LMB and LMA&C had an effect only on overlying water and surface 10~40 mm sediment, and CN was effective only on sediments. LMB and LMA&C transformed NH
4 Cl-P, BD-P, NaOH-SRP and NaOH-NRP in surface 20 mm sediment to HCl-P and Residual-P on day 60. CN transformed NaOH-SRP and NaOH-NRP to BD-P, resulting in the increase in NH4 Cl-P. LMB+CN and LMA&C+CN sequestered P in the surface 20 mm mainly as HCl-P and Residual-P, and mainly as BD-P in −20~−60 mm. Results indicate that the combination of capping by La-based material and oxidation by CN is a promising method for sediment P control. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
43. Overview of the Eutrophication in Romanian Lakes and Reservoirs.
- Author
-
Dumitran, Gabriela Elena, Vuta, Liana Ioana, and Popa, Bogdan
- Subjects
EUTROPHICATION ,WATER quality monitoring ,LAKES ,LAKE management - Abstract
In this paper, attention is drawn to the deterioration of Romanian surface water ecosystems due to eutrophication, an important environmental issue both at national and international levels. An inventory of existing studies dealing with the issue of the eutrophication of lakes and reservoirs in Romania is made, aiming to identify the main problems Romania is facing in monitoring, classifying, and managing eutrophic ecosystems. On Web of Science, the keyword "Eutrophication", with "Romania" as country/region, leads to 50 publications, which are analyzed in this review. The number of articles found does not reflect the real environmental issue represented by eutrophic lakes and reservoirs in Romania. At a national level, only 126 lakes and reservoirs have been monitored and assessed between 2018 and 2020, in terms of ecological status/ecological potential. Thus, at a global evaluation, 77% of natural lakes and 33% of artificial ones do not reach the quality objectives. The results of this study showed that the frequency of measurements taken by water quality indicators is not the strongest point of measurement campaigns, as it is not sufficient for the diagnosis of eutrophic lakes, and supplementary measures must be undertaken to better understand and mitigate this phenomenon. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. The Effects of a Fishery Complementary Photovoltaic Power Plant on the Near-Surface Meteorology and Water Quality of Coastal Aquaculture Ponds.
- Author
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Song, Fawen, Lu, Zhiqiang, Guo, Zhouhua, Wang, Yi, and Ma, Li
- Subjects
PHOTOVOLTAIC power systems ,WATER shortages ,WATER quality ,TERRITORIAL waters ,FISHERIES ,PONDS ,COAL-fired power plants - Abstract
To date, most studies focus on the ecological and environmental effects of land-based photovoltaic (PV) power plants, while there is a dearth of studies examining the impacts of water-based PV power plants. The effects of a fishery complementary PV power plant, a kind of water-based PV technology, on the near-surface meteorology and aquaculture water environment were investigated in coastal aquaculture ponds in southeast China. The results showed that PV prevented 89~93% of the solar radiation on the surface of the pond, resulting in an average reduction in water temperature of 1.5 °C and a substantial decrease in light intensity of 94%. Furthermore, it weakened the wind speed by 41~50% and elevated the surface air temperature by an average of 0.6 °C. In addition, PV power results in an impressive decrease in chlorophyll-α of 72~94% and a notable increase in dissolved oxygen (DO) concentrations of 8~24%. PV power also reduced the concentration of labile phosphate, active silicate, total nitrogen, total phosphorus, and total organic carbon. However, the PV power did not have a substantial influence on the concentrations of nitrate and ammonium. Our results highlight that fishery complementary PV power plants may be able to improve water quality and benefit shade-loving species. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. Harnessing Phosphorous (P) Fertilizer-Insensitive Bacteria to Enhance Rhizosphere P Bioavailability in Legumes.
- Author
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Afkairin, Antisar, Dixon, Mary M., Buchanan, Cassidy, Ippolito, James A., Manter, Daniel K., Davis, Jessica G., and Vivanco, Jorge M.
- Subjects
RHIZOBACTERIA ,PHOSPHATE fertilizers ,SUSTAINABILITY ,BIOAVAILABILITY ,COMMON bean ,LEGUMES - Abstract
Phosphorous (P) is widely used in agriculture; yet, P fertilizers are a nonrenewable resource. Thus, mechanisms to improve soil P bioavailability need to be found. Legumes are efficient in P acquisition and, therefore, could be used to develop new technologies to improve soil P bioavailability. Here, we studied different species and varieties of legumes and their rhizosphere microbiome responses to low-P stress. Some varieties of common beans, cowpeas, and peas displayed a similar biomass with and without P fertilization. The rhizosphere microbiome of those varieties grown without P was composed of unique microbes displaying different levels of P solubilization and mineralization. When those varieties were amended with P, some of the microbes involved in P solubilization and mineralization decreased in abundance, but other microbes were insensitive to P fertilization. The microbes that decreased in abundance upon P fertilization belonged to groups that are commonly used as biofertilizers such as Pseudomonas and Azospirillum. The microbes that were not affected by P fertilization constitute unique species involved in P mineralization such as Arenimonas daejeonensis, Hyphomicrobium hollandicum, Paenibacillus oenotherae, and Microlunatus speluncae. These P-insensitive microbes could be used to optimize P utilization and drive future sustainable agricultural practices to reduce human dependency on a nonrenewable resource. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Pseudomonas taetrolens ULE-PH5 and Pseudomonas sp. ULE-PH6 Isolated from the Hop Rhizosphere Increase Phosphate Assimilation by the Plant.
- Author
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Ghoreshizadeh, Seyedehtannaz, Calvo-Peña, Carla, Ruiz-Muñoz, Marina, Otero-Suárez, Rebeca, Coque, Juan José R., and Cobos, Rebeca
- Subjects
PLANT assimilation ,PLANT growth-promoting rhizobacteria ,HOPS ,GREENHOUSES ,PSEUDOMONAS ,RHIZOSPHERE - Abstract
Most of the phosphorus incorporated into agricultural soils through the use of fertilizers precipitates in the form of insoluble salts that are incapable of being used by plants. This insoluble phosphorus present in large quantities in soil forms the well-known "phosphorus legacy". The solubilization of this "phosphorus legacy" has become a goal of great agronomic importance, and the use of phosphate-solubilizing bacteria would be a useful tool for this purpose. In this work, we have isolated and characterized phosphate-solubilizing bacteria from the rhizosphere of hop plants. Two particular strains, Pseudomonas taetrolens ULE-PH5 and Pseudomonas sp. ULE-PH6, were selected as plant growth-promoting rhizobacteria due to their high phosphate solubilization capability in both plate and liquid culture assays and other interesting traits, including auxin and siderophore production, phytate degradation, and acidic and alkaline phosphatase production. These strains were able to significantly increase phosphate uptake and accumulation of phosphorus in the aerial part (stems, petioles, and leaves) of hop plants, as determined by greenhouse trials. These strains are promising candidates to produce biofertilizers specifically to increase phosphate adsorption by hop plants. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
47. Experimental Investigation of Lanthanum-Modified Reinforced Composite Material for Phosphorus Removal.
- Author
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Liu, Yan and Zhu, Lingfeng
- Subjects
PHOSPHORUS ,HOT water ,RAW materials ,LANTHANUM ,FLY ash - Abstract
Adsorption stands as an economically viable, efficient, recyclable, operationally straightforward, cost-effective, and low-sludge method extensively employed for phosphorus removal. In an effort to enhance the adsorption capabilities of the adsorbent, this study employs the rare-earth metal lanthanum in conjunction with the group's previously researched high-efficiency composite industrial residue phosphorus removal materials (EPRC) for modification, thereby generating lanthanum-modified reinforced composite phosphorus removal materials (La-EPRC). Subsequently, the novel material undergoes static modification, followed by experimental investigations into static and dynamic adsorption for phosphorus removal. Static adsorption experiments reveal optimal phosphorus removal efficiency when the initial phosphorus solution concentration is 20 mgP/L, with a La-EPRC particle dosage of 3 g/250 mL and a temperature of 25 °C. The removal efficiency of phosphorus particles is above 90% within the pH range of 4 to 10. Common coexisting anions in water, including Cl
− , SO4 2− , HCO3 − , and CO3 2− , demonstrate minimal impact on the efficacy of phosphorus removal. La-EPRC demonstrates a robust adsorption stability in both water and hot water environments. In a 2.5 mol/L NaOH solution, effective desorption of La-EPRC particles is observed, facilitating material regeneration. The raw materials for La-EPRC are easily accessible and cost-effective, imparting significant potential for widespread applications. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
48. Nanoparticles for Mitigation of Harmful Cyanobacterial Blooms.
- Author
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Tseytlin, Ilana N., Antrim, Anna K., and Gong, Ping
- Subjects
CYANOBACTERIAL blooms ,PHOTOCATALYSIS ,PLANKTON blooms ,FLOCCULATION ,CYTOTOXINS ,CELL membranes ,BODIES of water - Abstract
With the rapid advancement of nanotechnology and its widespread applications, increasing amounts of manufactured and natural nanoparticles (NPs) have been tested for their potential utilization in treating harmful cyanobacterial blooms (HCBs). NPs can be used as a photocatalyst, algaecide, adsorbent, flocculant, or coagulant. The primary mechanisms explored for NPs to mitigate HCBs include photocatalysis, metal ion-induced cytotoxicity, physical disruption of the cell membrane, light-shielding, flocculation/coagulation/sedimentation of cyanobacterial cells, and the removal of phosphorus (P) and cyanotoxins from bloom water by adsorption. As an emerging and promising chemical/physical approach for HCB mitigation, versatile NP-based technologies offer great advantages, such as being environmentally benign, cost-effective, highly efficient, recyclable, and adaptable. The challenges we face include cost reduction, scalability, and impacts on non-target species co-inhabiting in the same environment. Further efforts are required to scale up to real-world operations through developing more efficient, recoverable, reusable, and deployable NP-based lattices or materials that are adaptable to bloom events in different water bodies of different sizes, such as reservoirs, lakes, rivers, and marine environments. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Conflicts of the Land Use and Ecosystem Services in the Riverine Landscape of the Little Danube.
- Author
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Miklósová, Viktória and Kozelová, Ivana
- Subjects
ECOSYSTEM services ,LAND use ,LANDSCAPES ,SOCIOECONOMIC factors ,DRINKING water - Abstract
Ecosystem benefits, now known as ecosystem services (ESs), confront continuous threats from human activities and lack adequate protection, often suffering degradation and destruction despite their inherent advantages. This paper aims to introduce the geosystem approach as an exact scientific basis for assessing ESs. By emphasizing the interconnectedness of abiotic and biotic components within ecosystems, this method involves in-depth research across landscape dimensions and socioeconomic factors influencing the utilization of ecosystem services (ESs). It highlights a deep understanding of their connections and interactions. The key operational units, termed landscape–ecological complexes or geoecological complexes, result from fundamental research. Their interpretation as potentially useful for the chosen ESs is already an applied procedure. ES assessment employs two approaches: participatory and biophysical assessments. The outcomes contribute to the development of management measures for preserving or enhancing ESs in the broader study area. Methodological procedures were tested in the Little Danube model area, a unique lowland stream in Central Europe's Rye Island and a significant drinking water reservoir. The assessment results provide a foundation, supporting arguments, and criteria for ecologically appropriate landscape planning, as well as the sustainable management, utilization, and conservation of natural resources. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
50. Macroinvertebrate Community Responses to Multiple Pressures in a Peri-Urban Mediterranean River.
- Author
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Latinopoulos, Dionissis, Ntislidou, Chrysoula, Lazarina, Maria, Papaevangelou, Vassiliki, Akratos, Christos, and Kagalou, Ifigenia
- Abstract
Despite peri-urban areas being crucial for ecosystem service provisioning, they usually become degraded, as they are burdened with effluents from urban production activities. Such is the case of Laspias River (Thrace, Greece), where a series of diffuse and point pollution sources are met throughout its course, neglecting the fact that it discharges into a protected area. In an attempt to assist possible management implications in this less-researched river, two years of investigative monitoring provided the insight to test the effect of abiotic parameters in the benthic invertebrate biota and water quality, in turn. The results revealed an avalanche of pressures, where nutrients and organic pollution loads diminish richness and biodiversity, losing any temporal or seasonal pattern, resulting in biotic (taxonomic/functional) homogenization. The river is at a tipping point, and tailored measures must be designed and implemented immediately. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
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