Reconstruction of multi-decadal groundwater level time-series using a lumped conceptual model

Multi-decadal groundwater level records, which provide information about long-term variability and trends, are relatively rare. Whilst a number of studies have sought to reconstruct river flow records, there have been few attempts to reconstruct groundwater level time-series over a number of decades. Using long rainfall and temperature records, we developed and applied a methodology to do this using a lumped conceptual model. We applied the model to six sites in the UK, in four different aquifers: Chalk, limestone, sandstone and Greensand. Acceptable models of observed monthly groundwater levels were generated at four of the sites, with maximum Nash–Sutcliffe Efficiency scores of between 0.84 and 0.93 over the calibration and evaluation periods, respectively. These four models were then used to reconstruct the monthly groundwater level time-series over approximately 60 years back to 1910. Uncertainty in the simulated levels associated with model parameters was assessed using the Generalized Likelihood Uncertainty Estimation method. Known historical droughts and wet period in the UK are clearly identifiable in the reconstructed levels, which were compared using the Standardized Groundwater Level Index. Such reconstructed records provide additional information with which to improve estimates of the frequency, severity and duration of groundwater level extremes and their spatial coherence, which for example is important for the assessment of the yield of boreholes during drought period

User's manual for BGS GISGroundwater: a numerical model to simulate groundwater levels for ArcGIS 10.0

This is a user manual of BGS GISGroundwater that produces the depth to groundwater beneath the land surface. BGS GISGroundwater uses standard GIS datasets as inputs and implements data preparation, numerical modelling, post-processing and the visualisation of the modelled results all within the GIS environment. It allows non-modellers, such as scientists and students, to easily and efficiently build up groundwater flow models in ArcMap using GIS layers. For example, only few hours are needed to construct a numerical regional groundwater flow model using it with great flexibility. Therefore it is useful for carrying out preliminary groundwater flow modelling or evaluating hydrogeological conceptual models, before carrying out detailed costly groundwater modelling using one of traditional groundwater flow models. This manual firstly introduces BGS GISGroundwater, and then explains its installation process and interface. The step-by-step tutorial materials are also provided to guide users to learn quickly how to use this tool

The association between the insertion/deletion polymorphism of the angiotensin converting enzyme gene and hypertension, as well as environmental, biochemical and anthropometric factors

Background. Arterial hypertension is caused by environmental factors and genetic predisposition. Objective. The aim of this study was to assess the association between the angiotensin converting enzyme (ACE) gene variants and environmental factors, biochemical and anthropometric parameters and the incidence of hypertension. Material and methods. A total of 73 patients, aged 24 to 68, with Body Mass Index (BMI) above 25 kg/m2 took part in this study. Nutrient intake was assessed with a diet based on consumption records. The ACE gene insertion/deletion (I/D) polymorphism was determined by the polymerase chain reaction (PCR) method. Results. Normal pressure predominated in persons with genotype II (59.1%), whereas hypertension in persons with genotype ID (55.2%). The frequency of the D allele was 5% higher in the hypertensive group (53% vs. 48%), but this difference was not statistically significant. The percentage of patients who consumed alcohol and smoked cigarettes in the D allele group was higher than in the I allele group. People with the D allele had lower vitamin D intake and higher copper intake than carriers of the allele I. The highest vitamin D intake was found in people with genotype II, and the differences were significant compared to patients with ID genotype. People with the D allele consumed more carbohydrates and less protein than those with the I allele, but these differences were not statistically significant. Conclusions. Hypertensive subjects were more frequent DD and ID genotypes, whereas normotensive subjects - the II genotype. People with the D allele had lower vitamin D and protein intake, while the carbohydrate and copper intake was higher than those with the I allele. The group with the D allele had a higher percentage of smokers and alcohol drinkers. Our studies have shown a relationship between environmental and genetic factors and hypertension, but more research is needed.Wprowadzenie. Nadciśnienie tętnicze jest spowodowane przez czynniki środowiskowe i predyspozycje genetyczne. Cel. Celem badań była ocena związku pomiędzy wariantami genu ACE oraz czynnikami środowiskowymi, biochemicznymi i antropometrycznymi a występowaniem nadciśnienia. Materiał i metody. W badaniu wzięło udział 73 pacjentów, w wieku od 24 do 68 lat, z BMI >25kg/m2. Spożycie składników pokarmowych z dietą oceniano na podstawie zapisów spożycia. Polimorfizm I/D genu ACE określono metodą PCR. Wyniki. Prawidłowe ciśnienie dominowało u osób z genotypem II (59,1%), natomiast nadciśnienie u osób z genotypem ID (55,2%). Częstotliwość allelu D była większa o 5% w grupie z nadciśnieniem (53% vs. 48%), jednak różnica ta nie była statystycznie istotna. Odsetek pacjentów, którzy spożywali alkohol i palili papierosy w grupie z allelem D był wyższy niż w grupie z allelem I. Osoby z allelem D charakteryzowały się niższym spożyciem witaminy D i wyższym spożyciem miedzi niż nosiciele allelu I. Największe spożycie witaminy D stwierdzono u osób z genotypem II, a różnice były znaczące w stosunku do pacjentów z genotypem ID. Ludzie z allelem D spożywali więcej węglowodanów i mniej białka niż osoby z allelem I, ale różnice te nie były istotne statystycznie. Wnioski. U osób z nadciśnieniem tętniczym częściej występowały genotypy DD oraz ID, podczas gdy wśród osób z prawidłowym nadciśnieniem – genotyp II. U osób z allelem D było niższe spożycie witaminy D i białka, natomiast większe było spożycie węglowodanów i miedzi niż u osób z allelem I. W grupie z allelem D stwierdzono większy odsetek osób palących papierosy i pijących alkohol. Nasze badania wykazały związek pomiędzy czynnikami środowiskowymi i genetycznymi oraz nadciśnieniem, ale niezbędne są dalsze analizy w tym obszarze