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2.
Environ Res ; 233: 116434, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37343753

RESUMO

Vegetated filter strips (VFS) act as buffer zones between fields and water bodies that are supposed to retain incoming runoff, sediment, and nutrients. The factors that govern nutrient retention and cycling in VFS are complex and act in all three dimensions. A key element that determines VFS effectivity is flow type, e.g., sheet vs. concentrated flow. These aspects are, however, often insufficiently accounted for in VFS research and design recommendations. In this study, we attempt to tackle these shortcomings by examining the nutrient distribution in detail at two field-VFS transitions, applying a three-dimensional sampling array together with extensive laboratory analyses. Concentrated runoff was the dominant type we found and we argue that flow convergence is the norm rather than the exception. Further complicating this issue is that entry locations of runoff may vary, calling for more sophisticated sampling designs. Overall trends were similar across the analyzed nutrient fractions (different K- and P-pools) and there were distinct trends of decreasing nutrients along the longitudinal (from the field to the VFS) and vertical planes. The horizontal plane (from outside to inside the area of concentrated flow) showed mostly inconclusive or U-shaped gradients. Both sites were similar and close to each other, nevertheless, there were significant differences that affected nutrient retention in the VFS which were linked to site-specific factors. The spatial extent (i.e., width) is often considered the main variable in VFS designs. However, other VFS traits such as vegetation type and structure, as well as external factors such as field topography and the severity of erosive events are equally important and should be attributed more significance.


Assuntos
Agricultura , Fósforo , Agricultura/métodos
3.
Environ Monit Assess ; 195(4): 512, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36964829

RESUMO

Managing agricultural watersheds in an environmentally friendly manner necessitate the strategic implementation of well-targeted sustainable land management (SLM) practices that limit soil and nonpoint source pollution losses and translocation. Watershed-scale SLM-scenario modeling has the potential to identify efficient and effective management strategies from the field to the integrated landscape level. In a case study targeting a 66-hectare watershed in Petzenkirchen, Lower Austria, the Soil and Water Assessment Tool (SWAT) was utilized to evaluate a variety of locally adoptable SLM practices. SWAT was calibrated and validated (monthly) at the catchment outlet for flow, sediment, nitrate-nitrogen (NO3-N), ammonium nitrogen (NH4-N), and mineralized phosphorus (PO4-P) using SWATplusR. Considering the locally existing agricultural practices and socioeconomic and environmental factors of the research area, four conservation practices were evaluated: baseline scenario, contour farming (CF), winter cover crops (CC), and a combination of no-till and cover crops (NT + CC). The NT + CC SLM practice was found to be the most effective soil conservation practice in reducing soil loss by around 80%, whereas CF obtained the best results for decreasing the nutrient loads of NO3-N and PO4-P by 11% and 35%, respectively. The findings of this study imply that the setup SWAT model can serve the context-specific performance assessment and eventual promotion of SLM interventions that mitigate on-site land degradation and the consequential off-site environmental pollution resulting from agricultural nonpoint sources.


Assuntos
Solo , Qualidade da Água , Conservação dos Recursos Naturais , Áustria , Monitoramento Ambiental/métodos , Agricultura/métodos , Nitrogênio/análise
4.
J Environ Radioact ; 257: 107078, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36423536

RESUMO

To investigate the effects of converting forests into vineyards typical to Zarivar Lake watershed, Iran, which occurred mainly in the 1970s and 80s, on soil erosion,137Cs and 210Pbex, being mid-and-long-term soil loss tracers, were applied. In Chernobyl-contaminated areas like those found in some parts of Europe and Asia, the proportion of 137Cs Chernobyl fallout needs to be determined to convert 137Cs inventories into soil erosion rates. To do so, Pu radioisotopes were applied for the first time in Iran. The soil samples were gathered from two adjacent, almost similar hillslopes under natural forest (slope length: 250 m; slope gradient: 20%) and rainfed vineyard (slope length: 200 m; slope gradient: 17%). 137Cs/239+240Pu ratios indicated that 49.8 ± 10.0% of 137Cs originated from Chernobyl. The net soil erosion rates derived by 137Cs, and 210Pbex approaches were 5.0 ± 1.1 and 5.9 ± 2.9 Mg ha-1 yr-1 in the forested hillslope, and 25.9 ± 5.7 and 32.5 ± 14.5 Mg ha-1 yr-1 in the vineyard hillslope, respectively. Both 137Cs and 210Pbex highlighted that deforestation increased soil erosion by around five times. Moreover, the impacts of deforestation on soil physicochemical properties were investigated in surface and subsurface soils. Compared to forested hillslope, soil organic carbon stock in the upper 40 cm of the vineyard reduced by 14 Mg C ha-1 (29%), 8 Mg C ha-1 of which was removed by erosion within 35 years, and the remaining have likely been lost via emissions (6 Mg C ha-1). The vineyard topsoil experienced the most dramatic drops in percolation stability (PS), sealing index, and organic matter by about 55, 51, and 49%, respectively. Among all measured physicochemical properties, PS showed the greatest sensitivity to land-use change. Overall, the present study's findings confirmed that deforestation for agricultural purposes triggered soil loss, deteriorated soil quality and possibly contributed to the reduction of the lake's water quality and climate change.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Solo/química , Chumbo , Erosão do Solo , Irã (Geográfico) , Conservação dos Recursos Naturais , Carbono , Radioisótopos de Césio/análise , Poluentes Radioativos do Solo/análise
5.
Int J Mol Sci ; 23(19)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36232576

RESUMO

Antimicrobial resistance (AMR) is a public health issue attributed to the misuse of antibiotics in human and veterinary medicine. Since AMR surveillance requires a One Health approach, we sampled nine interconnected compartments at a hydrological open-air lab (HOAL) in Austria to obtain six bacterial species included in the WHO priority list of antibiotic-resistant bacteria (ARB). Whole genome sequencing-based typing included core genome multilocus sequence typing (cgMLST). Genetic and phenotypic characterization of AMR was performed for all isolates. Eighty-nine clinically-relevant bacteria were obtained from eight compartments including 49 E. coli, 27 E. faecalis, 7 K. pneumoniae and 6 E. faecium. Clusters of isolates from the same species obtained in different sample collection dates were detected. Of the isolates, 29.2% were resistant to at least one antimicrobial. E. coli and E. faecalis isolates from different compartments had acquired antimicrobial resistance genes (ARGs) associated with veterinary drugs such as aminoglycosides and tetracyclines, some of which were carried in conjugative and mobilizable plasmids. Three multidrug resistant (MDR) E. coli isolates were found in samples from field drainage and wastewater. Early detection of ARGs and ARB in natural and farm-related environments can identify hotspots of AMR and help prevent its emergence and dissemination along the food/feed chain.


Assuntos
Antibacterianos , Drogas Veterinárias , Aminoglicosídeos , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Animais , Antibacterianos/farmacologia , Áustria , Bactérias/genética , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/genética , Humanos , Testes de Sensibilidade Microbiana , Tetraciclinas , Águas Residuárias , Sequenciamento Completo do Genoma
6.
Hydrol Process ; 36(8): e14667, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36247077

RESUMO

Understanding the role of soil moisture and other controls in runoff generation is important for predicting runoff across scales. This paper aims to identify the degree of non-linearity of the relationship between event peak runoff and potential controls for different runoff generation mechanisms in a small agricultural catchment. The study is set in the 66 ha Hydrological Open Air Laboratory, Austria, where discharge was measured at the catchment outlet and for 11 sub-catchments or hillslopes with different runoff generation mechanisms. Peak runoff of 73 events was related to three potential controls: event precipitation, soil moisture and groundwater levels. The results suggest that the hillslopes dominated by ephemeral overland flow exhibit the most non-linear runoff generation behaviour for its controls; runoff is only generated above a threshold of 95% of the maximum soil moisture. Runoff generation through tile drains and in wetlands is more linear. The largest winter and spring events at the catchment outlet are caused by runoff from hillslopes with shallow flow paths (ephemeral overland flow and tile drainage mechanisms), while the largest summer events are caused by other hillslopes, those with deeper flow paths or with saturation areas throughout the year. Therefore, the response of the entire catchment is a mix of the various mechanisms, and the groundwater contribution makes the response more linear. The implications for hydrological modelling are discussed.

7.
MethodsX ; 9: 101826, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091658

RESUMO

Wind erosion is a process in which soil particles are detached from soils and transported downwind. One effective measure to reduce wind erosion are vegetated windbreaks such as hedgerows as they reduce wind speeds and likewise the forces which detach and transport soil particles. However, the planting of new windbreaks is driven by policy decisions as well as planning considerations. To get an initial idea of potential locations for new windbreaks, we present an automated routine as a model in ESRI ArcGIS Pro to propose plantation locations. The main input to the model is a wind erosion risk map. The results are potential locations for windbreaks that are ranked according to their suitability. The model parameters are adjustable, transferable to other regions and can be altered by to the user's needs.•Limit the wind erosion risk map to the most prone fields•Selection of unprotected sites perpendicular to the main wind direction•Suggestions for suitable sites for the potential planting of new windbreaks.

8.
Environ Res ; 214(Pt 1): 113774, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35777437

RESUMO

Vegetation plays a vital role in regulating hydrological cycle and controlling soil erosion at multiple spatial and temporal scales. Establishing shrub-grass community is one of the widely adopted practices to increase rainfall infiltration and reduce soil erosion in water-limited and highland regions. To understand the effects of such vegetation communities on soil erosion and overland flow under different rainfall regimes at the hillslope scale, we conducted rainfall simulation experiments by setting up parallel plots at fixed slope of 15° including unvegetated (coverage 0%), shrub only (coverage 50%), grass only (coverage 50%), and shrub-grass covered (coverages 25%, 50%, 75%, and 100%) and constant rainfall intensities of 30, 60, and 90 mm h-1 rainfalls lasting 60 min each after the initiation of overland flow. Two native species Lespedeza bicolor and Carex giraldiana, distributed in the soil sampling region were planted on the plots to achieve designed coverages. We found that the overland flow and sediment load from vegetated slopes were reduced by 9%-58% and 27%-98%, respectively, compared with unvegetated slopes while the infiltration rate increased by over 45%. Shrub-grass community reduced the overland flow and sediment yield more significantly than shrub only and grass only treatments with the same coverage of 50% under three rainfall intensities. In addition, the overland flow rate linearly decreased while the mean sediment yield exponentially reduced against the increase in shrub-grass community coverage. Hydrodynamically, shrub-grass communities not only increased the critical hydrodynamic forces for the initiating soil erosion but also increased the resistance coefficient leading to reduce overland flow velocity, stream power, and thus soil erosion from the vegetative slope even under extreme rainfalls. Our research highlights the importance of developing the shrub-grass communities to reduce the quantity and energy of overland flow and control soil erosion on the hillslopes in water-limited and highland regions.


Assuntos
Poaceae , Erosão do Solo , China , Monitoramento Ambiental , Chuva , Solo , Água , Movimentos da Água
9.
Sci Total Environ ; 756: 143699, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33307498

RESUMO

Antimicrobial resistance (AR) represents a global threat in human and veterinary medicine. In that regard, AR proliferation and dissemination in agricultural soils after manure application raises concerns on the enrichment of endogenous soil bacterial population with allochthonous antibiotic resistance genes (ARGs). Natural resilience of agricultural soils and background concentrations of ARGs play key roles in the mitigation of AR propagation in natural environments. In the present study, we carried out a longitudinal sampling campaign for two crop vegetation periods to monitor spatial and temporal changes in the abundance of seven clinically relevant ARGs (sul1, ermB, vanA, aph(3')-IIa, aph(3')-IIIa, blaTEM-1 and tet(W)) and ribosomal 16S RNA. The absolute and relative abundances of the selected ARGs were quantified in total community DNA extracted from agricultural (manured and non-manured) and forest soils, fresh pig faeces and manure slurry. We observed that ARG concentrations return to background levels after manure-induced exposure within a crop growing season, highlighting the resilience capacity of soil. Naturally occurring high background concentrations of ARGs can be found in forest soil in due distance under low anthropogenic influences. It was observed that pesticide application increases the concentrations of three out of seven ARGs tested (ermB, aph(3')-IIIa and tet(W)). Moreover, we noticed that the absolute abundances of sul1, vanA, ermB and blaTEM-1 resistance genes show an increase by 100- to 10,000- fold, from maturation of fresh pig faeces to manure. Outcomes of our study suggest that agricultural soil environments show a strong capacity to alleviate externally induced disturbances in endogenous ARG concentrations. Naturally occurring high concentrations of ARGs are present also in low human impacted environments represented by the indigenous resistome.


Assuntos
Antibacterianos , Solo , Animais , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Esterco , RNA Ribossômico 16S , Microbiologia do Solo , Suínos
10.
Hydrol Sci J ; 65(4): 524-535, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32257534

RESUMO

Optical disdrometers can be used to estimate rainfall erosivity; however, the relative accuracy of different disdrometers is unclear. This study compared three types of optical laser-based disdrometers to quantify differences in measured rainfall characteristics and to develop correction factors for kinetic energy (KE). Two identical PWS100 (Campbell Scientific), one Laser Precipitation Monitor (Thies Clima) and a first-generation Parsivel (OTT) were collocated with a weighing rain gauge (OTT Pluvio2) at a site in Austria. All disdrometers underestimated total rainfall compared to the rain gauge with relative biases from 2% to 29%. Differences in drop size distribution and velocity resulted in different KE estimates. By applying a linear regression to the KE-intensity relationship of each disdrometer, a correction factor for KE between the disdrometers was developed. This factor ranged from 1.15 to 1.36 and allowed comparison of KE between different disdrometer types despite differences in measured drop size and velocity.

11.
Hydrol Sci J ; 65(13): 2185-2195, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-33633428

RESUMO

The objective of this study is to investigate the factors that control event runoff characteristics at the small catchment scale. The study area is the Hydrological Open Air Laboratory, Lower Austria. Event runoff coefficient (Rc), recession time constant (Tc) and peak discharge (Qp) are estimated from hourly discharge and precipitation data for 298 events in the period 2013-2015. The results show that the Rc and their variability tend to be largest for the tile drainages (mean Rc = 0.09) and the main outlet (mean Rc = 0.08) showing larger Rc in January/February and smaller Rc in July/August. Tc does not vary much between the systems and tends to be largest at the main outlet (mean Tc = 6.5 h) and smallest for the tile drainages (mean Tc = 4.5 h). Groundwater levels explain the temporal variability of Rc and Tc more than soil moisture or precipitation, suggesting a role of shallow flow paths.

12.
J Appl Ecol ; 55(5): 2484-2495, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30147143

RESUMO

At the global scale, vineyards are usually managed intensively to optimize wine production without considering possible negative impacts on biodiversity and ecosystem services (ES) such as high soil erosion rates, degradation of soil fertility or contamination of groundwater. Winegrowers regulate competition for water and nutrients between the vines and inter-row vegetation by tilling, mulching and/or herbicide application. Strategies for more sustainable viticulture recommend maintaining vegetation cover in inter-rows, however, there is a lack of knowledge as to what extent this less intensive inter-row management affects biodiversity and associated ES.We performed a hierarchical meta-analysis to quantify the effects of extensive vineyard inter-row vegetation management in comparison to more intensive management (like soil tillage or herbicide use) on biodiversity and ES from 74 studies covering four continents and 13 wine-producing countries.Overall, extensive vegetation management increased above- and below-ground biodiversity and ecosystem service provision by 20% in comparison to intensive management. Organic management together with management without herbicides showed a stronger positive effect on ES and biodiversity provision than inter-row soil tillage.Soil loss parameters showed the largest positive response to inter-row vegetation cover. The second highest positive response was observed for biodiversity variables, followed by carbon sequestration, pest control and soil fertility. We found no trade-off between grape yield and quality vs. biodiversity or other ES. Synthesis and applications. Our meta-analysis concludes that vegetation cover in inter-rows contributes to biodiversity conservation and provides multiple ecosystem services. However, in drier climates grape yield might decrease without irrigation and careful vegetation management. Agri-environmental policies should therefore focus on granting subsidies for the establishment of locally adapted diverse vegetation cover in vineyard inter-rows. Future studies should focus on analysing the combined effects of local vineyard management and landscape composition and advance research in wine-growing regions in Asia and in the southern hemisphere.

13.
Sci Rep ; 8(1): 6471, 2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29674692

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

14.
Sci Rep ; 7(1): 17445, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29234045

RESUMO

Tillage is known for its adverse effects on soil biota, at least in arable agroecosystems. However, in vineyards effects might differ as tillage is often performed during dry periods or only in every other inter-row allowing species to re-colonise disturbed areas. We examined the response of earthworms (lumbricids), springtails (collembola) and litter decomposition to periodically mechanically disturbed (PMD) and permanently green covered (PGC) vineyard inter-rows and assessed whether site effects are altered by the surrounding landscape. In commercial vineyards in Austria we sampled earthworms by handsorting, springtails by soil coring and pitfall trapping and installed litter decomposition bags. Earthworm species diversity increased with plant biomass under PMD but not under PGC; earthworm density was unaffected by tillage but increased with plant biomass mainly at high soil quality (soil fertility index). Springtail species diversity was unaffected by tillage; springtail densities (mainly larger species) were reduced under PGC. Litter decomposition was little affected by investigated parameters. Landscape heterogeneity affected the functional diversity of surface springtails, but did not influence soil-dwelling springtails, earthworms or litter decomposition. We conclude that effects on soil biota of periodical tillage in vineyards need not necessarily be detrimental and will be modified by plant biomass and soil quality.


Assuntos
Artrópodes , Produção Agrícola , Fazendas , Oligoquetos , Plantas , Solo , Animais , Áustria , Biodiversidade , Biomassa
15.
Dtsch Arztebl Int ; 114(15): 263-268, 2017 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-28468714

RESUMO

BACKGROUND: Laparoscopic pancreatectomy is not yet established as a routine procedure everywhere in Germany or in other countries. Few data are available on its short- and long-term outcomes. METHODS: From 2008 onward, a working group initiated by 10 centers and currently comprising 34 centers has gathered data on all cases of laparoscopic pancreatectomy. Procedures in which laparoscopy was converted to open surgery are also included. RESULTS: The registry now contains 550 data sets representing 267 cases of benign disease, 244 malignancies, and 39 borderline tumors. The most common procedure was laparoscopic left pancreatectomy, followed by resection of the head of the pancreas and tumor enucleation. The most common intraoperative complication was hemorrhage, with a frequency of 3%. The rate of conversion to open surgery was 35%; if minilaparotomies are excluded, the conversion rate was only 16%. 39% of patients developed a pancreatic fistula after surgery (usually grade A or B, with 1.5% grade C) and 3% underwent reoperation because of postoperative hemorrhage. The procedure-related mortality was 1.3%. 91% of the patients reported only very mild postoperative pain. 6.7% newly developed diabetes mellitus after the procedure. CONCLUSION: The patient cohort in the registry consists of persons who were selected to undergo laparoscopic pancreatectomy by the participating hospital teams, and the data are thus inherently affected by selection bias. The operative procedures that they underwent reflect the current practice of laparoscopic pancreatectomy in Germany. The complication rates are similar to those of open surgery. Selection bias can be avoided only by a randomized trial.


Assuntos
Laparoscopia , Pancreatectomia/métodos , Neoplasias Pancreáticas/cirurgia , Feminino , Alemanha , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento
16.
PLoS One ; 11(9): e0163651, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27668746

RESUMO

BACKGROUND: Necrotising pancreatitis, and particularly infected necrosis, are still associated with high morbidity and mortality. Since 2011, a step-up approach with lower morbidity rates compared to initial open necrosectomy has been established. However, mortality and complication rates of this complex treatment are hardly studied thereafter. METHODS: The German Pancreatitis Study Group performed a multicenter, retrospective study including 220 patients with necrotising pancreatitis requiring intervention, treated at 10 hospitals in Germany between January 2008 and June 2014. Data were analysed for the primary endpoints "severe complications" and "mortality" as well as secondary endpoints including "length of hospital stay", "follow up", and predisposing or prognostic factors. RESULTS: Of all patients 13.6% were treated primarily with surgery and 86.4% underwent a step-up approach. More men (71.8%) required intervention for necrotising pancreatitis. The most frequent etiology was biliary (41.4%) followed by alcohol (29.1%). Compared to open necrosectomy, the step-up approach was associated with a lower number of severe complications (primary composite endpoint including sepsis, persistent multiorgan dysfunction syndrome (MODS) and erosion bleeding: 44.7% vs. 73.3%), lower mortality (10.5% vs. 33.3%) and lower rates of diabetes mellitus type 3c (4.7% vs. 33.3%). Low hematocrit and low blood urea nitrogen at admission as well as a history of acute pancreatitis were prognostic for less complications in necrotising pancreatitis. A combination of drainage with endoscopic necrosectomy resulted in the lowest rate of severe complications. CONCLUSION: A step-up approach starting with minimal invasive drainage techniques and endoscopic necrosectomy results in a significant reduction of morbidity and mortality in necrotising pancreatitis compared to a primarily surgical intervention.

17.
Water Res ; 101: 252-261, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27262553

RESUMO

Detection of enzymatic activities has been proposed as a rapid surrogate for the culture-based microbiological pollution monitoring of water resources. This paper presents the results of tests on four fully automated prototype instruments for the on-site monitoring of beta-d-glucuronidase (GLUC) activity. The tests were performed on sediment-laden stream water in the Hydrological Open Air Laboratory (HOAL) during the period of March 2014 to March 2015. The dominant source of faecal pollution in the stream was swine manure applied to the fields within the catchment. The experiments indicated that instrument pairs with the same construction design yielded highly consistent results (R(2) = 0.96 and R(2) = 0.94), whereas the results between different designs were less consistent (R(2) = 0.71). Correlations between the GLUC activity measured on-site and culture-based Escherichia coli analyses over the entire study period yielded R(2) = 0.52 and R(2) = 0.47 for the two designs, respectively. The correlations tended to be higher at the event scale. The GLUC activity was less correlated with suspended sediment concentrations than with E. coli, which is interpreted in terms of indicator applicability and the time since manure application. The study shows that this rapid assay can yield consistent results over a long period of on-site operation in technically challenging habitats. Although the use of GLUC activity as a proxy for culture-based assays could not be proven for the observed habitat, the study results suggest that this biochemical indicator has high potential for implementation in early warning systems.


Assuntos
Glucuronidase , Rios , Animais , Monitoramento Ambiental/instrumentação , Escherichia coli , Fezes/microbiologia , Suínos , Microbiologia da Água
18.
Sci Total Environ ; 542(Pt A): 935-45, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26562340

RESUMO

Our study examines the source aquifers and stream inputs of the seasonal water and nitrogen dynamics of a headwater agricultural catchment to determine the dominant driving forces for the seasonal dynamics in the surface water nitrogen loads and concentrations. We found that the alternating aquifer contributions throughout the year of the deep and shallow aquifers were the main cause for the seasonality of the nitrate concentration. The deep aquifer water typically contributed 75% of the total outlet discharge in the summer and 50% in the winter when the shallow aquifer recharges due to low crop evapotranspiration. The shallow aquifer supplied the vast majority of the nitrogen load to the stream due to the significantly higher total nitrogen concentration (11 mg-N/l) compared to the deep aquifer (0.50 mg-N/l). The main stream input pathway for the shallow aquifer nitrogen load was from the perennial tile drainages providing 60% of the total load to the stream outlet, while only providing 26% of the total flow volume. The diffuse groundwater input to the stream was the largest input to the stream (39%), but only supplied 27% to the total nitrogen load as the diffuse water was mostly composed of deep aquifer water.

19.
Sci Total Environ ; 532: 849-52, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26094798

RESUMO

Recently a rainfall erosivity map has been published. We show that the values of this map contain considerable bias because (i) the temporal resolution of the rain data was insufficient, which likely underestimates rain erosivity by about 20%, (ii) no attempt had been included to account for the different time periods that were used for different countries, which can modify rain erosivity by more than 50%, (iii) and likely precipitation data had been used instead of rain data and thus rain erosivity is overestimated in areas with significant snowfall. Furthermore, the seasonal distribution of rain erosivity is not provided, which does not allow using the erosivity map for erosion prediction in many cases. Although a rain erosivity map for Europe would be highly desirable, we recommend using the national erosivity maps until these problems have been solved. Such maps are available for many European countries.

20.
J Med Pract Manage ; 30(3): 208-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25807627

RESUMO

The landscape of the business world is changing; and now, more than ever, business owners are recognizing that life is filled with risks: known risk, calculated risk, and unexpected risk. Every day, businesses thrive or fail based on understanding the risk of owning and operating their business, and business owners are recognizing that there are alternative risk financing mechanisms other than simply taking out a basket of standard coverage as recommended by your friendly neighborhood agent. A captive insurance company is an insurance company established to provide a broad range of risk management capabilities to affiliated companies. The captive is owned by the business owner and can provide insurance to the business for potential future losses, whether or not the losses are already covered by a commercial carrier or are "self-insured." The premiums paid by your business are tax deductible. Meanwhile, the premiums that your captive collects are tax-free up to $1.2 million annually.


Assuntos
Seguro de Responsabilidade Civil/economia , Administração da Prática Médica/economia , Humanos , Fundos de Seguro , Gestão de Riscos , Impostos , Estados Unidos
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