Long-term lake sediment records and factors affecting the evolution of metal(loid) drainage from two mine sites (SW Finland)

2012 ◽  
Vol 114 ◽  
pp. 46-56 ◽  
Author(s):  
Annika Parviainen ◽  
Tommi Kauppila ◽  
Kirsti Loukola-Ruskeeniemi
2020 ◽  
Author(s):  
John Boyle ◽  
Ed Tipping ◽  
Jess Davies ◽  
Neil Rose ◽  
Simon Turner ◽  
...  

<p>To fully understand coupling between P and other macronutrients it is necessary to have both long-term data sets and process models, combining empirical reality with numerical simulation of coupling processes. Here, lake sediment records of N and P from four UK lakes are compared with model output from N14CP, a long-term, large-scale model of cycling and export of macronutrients from the landscape. The sediment records at the three lakes that have substantial lowland contributions reveal strongly increasing N and P loading through the late 19<sup>th</sup> century, with steady increases through the twentieth century. Corresponding changes in N and C isotopes are observed. However, the one mountain lake show maximum N and P loadings in the 19<sup>th</sup> century, with declines through the twentieth, consistent with a wholly different land use history. The N14CP model shows N and P increasing from mid 19<sup>th</sup> century for average lowland sites, in agreement with the lowland sediment records. The implications of these results for our knowledge about the history of P and N coupling and leaching from UK soils are discussed.</p>


2021 ◽  
Vol 18 (20) ◽  
pp. 5609-5638
Author(s):  
Madeleine Moyle ◽  
John F. Boyle ◽  
Richard C. Chiverrell

Abstract. Present-day lake water phosphorus (P) enrichment and accelerated P cycling are changes superimposed on a dynamic Holocene history of landscape development following glaciation, changes in climate, and long-term low-intensity human activity. Knowledge of the history of long-term P dynamics is essential for understanding present-day landscape P export and for managing both terrestrial and aquatic environments. This study is the first attempt to constrain the timing and magnitude of terrestrial changes in Holocene P dynamics across the Northern Hemisphere using lake sediment records. Here we reconstruct trajectories in terrestrial Holocene P dynamics for the Northern Hemisphere. We apply a simple process model to published lake sediment geochemical P records from 24 sites, producing records of landscape P yield and reconstructing lake water total phosphorus (TP) concentrations. Individual site trajectories of landscape P yield and lake water TP vary systematically, with differences attributable to local landscape development history. Three distinct traits are apparent. Mountain sites with minimal direct human impact show falling P supply and conform to conceptual models of natural soil development (Trait 1). Lowland sites where substantial (pre-)historic agriculture was present show progressively increasing P supply (Trait 2). Lowland sites may also show a rapid acceleration in P supply over the last few centuries, where high-intensity land use, including settlements and farming, is present (Trait 3). Where data availability permitted comparison, our reconstructed TP records agree well with monitored lake water TP data, and our sediment-inferred P yields are comparable to reported catchment export coefficients. Comparison with diatom-inferred TP reveals good agreement for recent records. Our reconstructions form the first systematic assessment of average terrestrial P export for the Northern Hemisphere over the Holocene and provide the empirical data needed for constraining long-term landscape P cycling models and values for terrestrial P export that could be used for ocean P cycling models. The long-term perspective provided by our sediment-inferred TP can be used to identify pre-disturbance baselines for lake water quality, information essential to target-driven lake management. We find the first detectable anthropogenic impacts on P cycling ca. 6000 BP, with more substantial impacts as early as 3000 BP. Consequently, to characterize pre-disturbance lake P conditions at Trait 2 and Trait 3 sites, it is necessary to consider time periods before the arrival of early farmers. Our use of trait classifications has a predictive power for sites without sediment records, allowing prediction of TP baselines and P trajectories based on regional landscape development history.


2021 ◽  
Author(s):  
Madeleine Moyle ◽  
John Francis Boyle ◽  
Richard Christopher Chiverrell

Abstract. Present day lake water phosphorus (P) enrichment and accelerated P cycling are changes superimposed on a dynamic Holocene history of landscape recovery from glaciation, changes in climate, and long-term low-intensity human activity. Knowledge of the history of long-term P dynamics is essential for understanding present-day landscape P export and for managing both terrestrial and aquatic environments. This study is the first attempt to constrain the timing and magnitude of terrestrial changes in Holocene P dynamics across the Northern Hemisphere using lake sediment records. Here we reconstruct trajectories in terrestrial Holocene P dynamics for the Northern Hemisphere. We apply a simple process model to published lake sediment geochemical P records from 24 sites, producing records of landscape P yield and reconstructing lake water total phosphorus (TP) concentrations. Individual site trajectories of landscape P yield and lake water TP vary systematically, with differences attributable to local landscape development history. Three distinct traits are apparent. Mountain sites with minimal direct human impact show falling P supply and conform to conceptual models of natural soil development (Trait 1). Lowland sites where substantial (pre-)historic agriculture was present show progressively increasing P supply (Trait 2). Lowland sites may also show a rapid acceleration in P supply over the last few centuries, where high intensity land use, including settlements and farming, are present (Trait 3). Where data availability permitted comparison, our reconstructed TP records agree well with both monitored lake water TP data and diatom inferred TP, and our sediment inferred P yields are comparable to reported catchment export coefficients. Our reconstructions form the first systematic assessment of average terrestrial P export for the Northern Hemisphere over the Holocene and provide the empirical data needed for constraining long-term landscape P cycling models and values for terrestrial P export that could be used for ocean P cycling models. The long-term perspective provided by our sediment-inferred TP can be used to identify pre-disturbance baselines for lake water quality, information essential to target-driven lake management. We find the first detectable anthropogenic impacts on P cycling ca. 6000 BP, with more substantial impacts as early as 3000 BP. Consequently, to characterise pre-disturbance lake P conditions at Trait 2 and Trait 3 sites it is necessary to consider time periods before the arrival of early farmers. Our use of trait classifications has a predictive power for sites without sediment records, allowing prediction of TP baselines and P trajectories based on regional landscape development history.


Author(s):  
Юлия Владимировна Татаркова ◽  
Татьяна Николаевна Петрова ◽  
Олег Валериевич Судаков ◽  
Александр Юрьевич Гончаров ◽  
Ольга Николаевна Крюкова

В настоящей статье представлен обзор основных решений, доступных сегодня для формирования как краткосрочных, так и долгосрочных проекций заболеваемости болезней глаза и его придаточного аппарата в студенческой среде. С другой стороны, существует ряд проблем, связанных с многообразием факторов, влияющих на заболеваемость, статистической необоснованностью и противоречивостью имеющихся результатов анализа данных. Представлены результаты математического моделирования зависимости показателя заболеваемости от наиболее влиятельных факторов образовательной и социальной среды. Перечислены важнейшие направления разработки математических моделей распространения заболеваемости. С помощью разработанного программного комплекса проведена серия вычислительных экспериментов по оценке и прогнозированию заболеваемости обучающихся в вузах разного профиля. Показана эффективность применения методики многовариантного моделирования и прогнозирования, указаны их ограничения и возможности практического применения. По расположению обобщенной области благоприятного прогноза в факторном пространстве можно определить время воздействия неблагоприятных для зрения факторов, которое должно составлять не более 10 ... 11 часов в сутки, количество профилактических мероприятий должно составлять не менее 3 ... 4. При этом риск развития миопии составит не более 0,4, вероятность усталости глаз за компьютером составит не более 0,4, вероятность дискомфорта глаз на занятиях составит не более 0,15. Исходя из характера прогноза, определяется длительность диспансерного наблюдения, а также потребность профилактических мероприятий по устранению или ослаблению действия неблагоприятно влияющих социально-гигиенических и медико-биологических факторов конкретного больного. Использование прогностической матрицы в практическом здравоохранении позволяет существенно улучшить работу по профилактике офтальмологической заболеваемости и является одним из эффективных мероприятий диспансеризации студенческой молодежи, так как дает возможность выделить из числа обучающихся группу с высоким риском неблагоприятного исхода заболевания This article provides an overview of the main solutions available today for the formation of both short-term and long-term projections of the incidence of eye diseases and its adnexa in the student environment. On the other hand, there are a number of problems associated with a variety of factors affecting the incidence, statistical unreasonability and inconsistency of the available data analysis results. The results of mathematical modeling of the dependence of the incidence rate on the most influential factors of the educational and social environment are presented. The most important areas of developing mathematical models for the spread of morbidity are listed. With the help of the developed software package, a series of computational experiments was carried out to assess and predict the incidence of students in universities of various profiles. The effectiveness of the application of multivariate modeling and forecasting methods is shown, their limitations and practical application possibilities are indicated. By the location of the generalized region of favorable prognosis in the factor space, it is possible to determine the exposure time of factors unfavorable for vision, which should be no more than 10 ... 11 hours a day, the number of preventive measures should be at least 3 ... 4. At the same time, the risk of development myopia will be no more than 0.4, the probability of eye fatigue at the computer will be no more than 0.4, the likelihood of eye discomfort in the classroom will be no more than 0.15. Based on the nature of the forecast, the duration of the follow-up observation is determined, as well as the need for preventive measures to eliminate or weaken the action of adverse social, hygienic and biomedical factors of a particular patient. The use of the prognostic matrix in practical health care can significantly improve the work on the prevention of ophthalmic morbidity and is one of the effective medical examinations for students, since it makes it possible to distinguish among the students a group with a high risk of an unfavorable outcome of the disease


2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
M Poldrugovac ◽  
J E Amuah ◽  
H Wei-Randall ◽  
P Sidhom ◽  
K Morris ◽  
...  

Abstract Background Evidence of the impact of public reporting of healthcare performance on quality improvement is not yet sufficient to draw conclusions with certainty, despite the important policy implications. This study explored the impact of implementing public reporting of performance indicators of long-term care facilities in Canada. The objective was to analyse whether improvements can be observed in performance measures after publication. Methods We considered 16 performance indicators in long-term care in Canada, 8 of which are publicly reported at a facility level, while the other 8 are privately reported. We analysed data from the Continuing Care Reporting System managed by the Canadian Institute for Health Information and based on information collection with RAI-MDS 2.0 © between the fiscal years 2011 and 2018. A multilevel model was developed to analyse time trends, before and after publication, which started in 2015. The analysis was also stratified by key sample characteristics, such as the facilities' jurisdiction, size, urban or rural location and performance prior to publication. Results Data from 1087 long-term care facilities were included. Among the 8 publicly reported indicators, the trend in the period after publication did not change significantly in 5 cases, improved in 2 cases and worsened in 1 case. Among the 8 privately reported indicators, no change was observed in 7, and worsening in 1 indicator. The stratification of the data suggests that for those indicators that were already improving prior to public reporting, there was either no change in trend or there was a decrease in the rate of improvement after publication. For those indicators that showed a worsening trend prior to public reporting, the contrary was observed. Conclusions Our findings suggest public reporting of performance data can support change. The trends of performance indicators prior to publication appear to have an impact on whether further change will occur after publication. Key messages Public reporting is likely one of the factors affecting change in performance in long-term care facilities. Public reporting of performance measures in long-term care facilities may support improvements in particular in cases where improvement was not observed before publication.


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