The long-term impacts of forest removal on floodplain subsurface hydrology

Mapping Intimacies ◽

10.32469/10355/48694 ◽

2015 ◽

Author(s):

◽

Ramsey Elliott Kellner

Keyword(s):

Shallow Groundwater ◽

Bottomland Hardwood Forest ◽

Agricultural Field ◽

Subsurface Hydrology ◽

Pressure Transducers ◽

Creek Watershed ◽

Quantitative Understanding ◽

Long Term Impact ◽

Floodplain Hydrology

A study was implemented in fall 2010, in the Hinkson Creek Watershed, Missouri, USA to improve quantitative understanding of the long-term impact of forest removal on floodplain hydrology. Automated volumetric water content (VWC) probes and piezometers equipped with pressure transducers to monitor shallow groundwater (SGW) temperature and level were installed in a gridded study design within a historic agricultural field (Ag) and a remnant bottomland hardwood forest (BHF). Groundwater was analyzed for 49 physiochemical metrics. Results showed VWC to be significantly different between sites (p less than 0.01) during the study, with site averages of 33.1 and 32.8% at the Ag and BHF sites, respectively. Semi-variogram analyses results suggest historic forest removal and cultivation of the Ag site facilitated the development of strong VWC spatial dependency. SGW temperature range at the Ag site was 72% greater than at the BHF site. BHF groundwater contained significantly (p less than 0.05) higher concentrations of nutrients, while Ag groundwater was characterized by significantly (p less than 0.05) higher concentrations of trace elements. Collective results highlight the greater extent to which BHF vegetation impacts subsurface hydrology, relative to grassland/agricultural systems, and point to the value of reestablishing floodplain forests for freshwater routing, water quality, aquatic ecosystem conservation, and flood mitigation in mixed-land-use watersheds.

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Mortality of white spruce during a spruce beetle outbreak on the Kenai Peninsula in Alaska

Canadian Journal of Forest Research ◽

10.1139/x83-014 ◽

1983 ◽

Vol 13 (1) ◽

pp. 96-101 ◽

Cited By ~ 15

Author(s):

Richard A. Werner ◽

Edward H. Holsten

Keyword(s):

White Spruce ◽

Permanent Plots ◽

Kenai Peninsula ◽

South Central ◽

Creek Watershed ◽

Spruce Beetle ◽

Spruce Stands ◽

Long Term Impact ◽

The Impact

White spruce (Piceaglauca (Moench) Voss) stands in the Resurrection Creek watershed in south-central Alaska were infested by spruce bettles, Dendroctonusrufipennis Kirby, between 1974 and 1975. Thirty permanent plots were established within the infested area in 1976 to evaluate the immediate and long-term impact on white spruce stands. Plots were revisited annually for 5 years. Between 1976 and 1980, 29% of all white spruce was killed by spruce beetles. This loss accounted for 59% of the commercial white spruce volume in the watershed. Mortality was greatest in the larger diameter classes during the early part of the infestation, but smaller diameter trees were subsequently attacked as the number of noninfested trees declined. The impact of spruce beetles on structure and species composition of white spruce stands is given along with a discussion of management implications.

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Imaging the Golden Age: the coinage of Antoninus Pius

Papers of the British School at Rome ◽

10.1017/s0068246213000093 ◽

2013 ◽

Vol 81 ◽

pp. 211-246 ◽

Cited By ~ 4

Author(s):

Clare Rowan

Keyword(s):

Detailed Analysis ◽

Golden Age ◽

Third Century ◽

The Third ◽

Gold Silver ◽

Quantitative Understanding ◽

Long Term Impact ◽

Imperial Family ◽

Broad Understanding

Given that few ancient accounts of the reign of Antoninus Pius survive from antiquity, other monuments, in particular coinage, become important in reconstructing his reign. In this article coin hoards are used to reconstruct a quantitative understanding of Pius's numismatic imagery. It is clear from the results that the three different coin metals (gold, silver and aes) differed in their messages: while gold coinage emphasized the imperial family and the concept of pietas, silver and aes coinage focused on the emperor's concern for the grain supply (annona). This broad understanding of Pius's numismatic image is supplemented by more detailed analysis of coin iconography in particular years. The liberalitas and Britannia series of Pius are explored in depth. The study highlights coinage's role as one imperial monument among many, contributing to the communication of imperial ideologies. It is clear that the image of Pius as a virtuous emperor ruling in a ‘Golden Age’ was one cultivated by the imperial bureaucracy, and so it is not surprising that the concept features in the preserved texts. The long-term impact of Pius's coinage is also considered. In the absence of significant quantities of aes coinage struck by the Severans, the coinage of Pius continued to be of importance in many regions throughout the third century, conveying impressions of Empire among users well after the emperor's death.

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Impact of an historic underground gas well blowout on the current methane chemistry in a shallow groundwater system

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1711472115 ◽

2017 ◽

Vol 115 (2) ◽

pp. 296-301 ◽

Cited By ~ 14

Author(s):

Gilian Schout ◽

Niels Hartog ◽

S. Majid Hassanizadeh ◽

Jasper Griffioen

Keyword(s):

Manganese Oxides ◽

Isotopic Fractionation ◽

Shallow Groundwater ◽

Gas Well ◽

Reduction Of Iron ◽

Shallow Groundwater System ◽

Long Term Impact ◽

Methane Concentrations ◽

Iron And Manganese

Blowouts present a small but genuine risk when drilling into the deep subsurface and can have an immediate and significant impact on the surrounding environment. Nevertheless, studies that document their long-term impact are scarce. In 1965, a catastrophic underground blowout occurred during the drilling of a gas well in The Netherlands, which led to the uncontrolled release of large amounts of natural gas from the reservoir to the surface. In this study, the remaining impact on methane chemistry in the overlying aquifers was investigated. Methane concentrations higher than 10 mg/L (n = 12) were all found to have δ13C-CH4 values larger than −30‰, typical of a thermogenic origin. Both δ13C-CH4 and δD-CH4 correspond to the isotopic composition of the gas reservoir. Based on analysis of local groundwater flow conditions, this methane is not a remnant but most likely the result of ongoing leakage from the reservoir as a result of the blowout. Progressive enrichment of both δ13C-CH4 and δD-CH4 is observed with increasing distance and decreasing methane concentrations. The calculated isotopic fractionation factors of εC = 3 and εD = 54 suggest anaerobic methane oxidation is partly responsible for the observed decrease in concentrations. Elevated dissolved iron and manganese concentrations at the fringe of the methane plume show that oxidation is primarily mediated by the reduction of iron and manganese oxides. Combined, the data reveal the long-term impact that underground gas well blowouts may have on groundwater chemistry, as well as the important role of anaerobic oxidation in controlling the fate of dissolved methane.

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An ecohydrologic model for a shallow groundwater urban environment

Water Science & Technology ◽

10.2166/wst.2014.299 ◽

2014 ◽

Vol 70 (11) ◽

pp. 1789-1797 ◽

Cited By ~ 5

Author(s):

Sam Arden ◽

Xin (Cissy) Ma ◽

Mark Brown

Keyword(s):

Urban Environment ◽

Water System ◽

Shallow Groundwater ◽

Realistic Model ◽

Canopy Interception ◽

Hydrologic Processes ◽

Urban Water System ◽

Complex Interactions ◽

Quantitative Understanding

The urban environment is a patchwork of natural and artificial surfaces that results in complex interactions with and impacts to natural hydrologic cycles. Evapotranspiration is a major hydrologic flow that is often altered through urbanization, although the mechanisms of change are sometimes difficult to tease out due to difficulty in effectively simulating soil–plant–atmosphere interactions. This paper introduces a simplified yet realistic model that is a combination of existing surface runoff and ecohydrology models designed to increase the quantitative understanding of complex urban hydrologic processes. Results demonstrate that the model is capable of simulating the long-term variability of major hydrologic fluxes as a function of impervious surface, temperature, water table elevation, canopy interception, soil characteristics, precipitation and complex mechanisms of plant water uptake. These understandings have potential implications for holistic urban water system management.

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Crisis Phones - Suicide Prevention Versus Suggestion/Contagion Effects

Crisis ◽

10.1027/0227-5910/a000313 ◽

2015 ◽

Vol 36 (3) ◽

pp. 220-224 ◽

Cited By ~ 3

Author(s):

Steven Stack

Keyword(s):

Suicide Prevention ◽

Contagion Effects ◽

Long Term Impact

Abstract. Background: There has been no systematic work on the short- or long-term impact of the installation of crisis phones on suicides from bridges. The present study addresses this issue. Method: Data refer to 219 suicides from 1954 through 2013 on the Skyway Bridge in St. Petersburg, Florida. Six crisis phones with signs were installed in July 1999. Results: In the first decade after installation, the phones were used by 27 suicidal persons and credited with preventing 26 or 2.6 suicides a year. However, the net suicide count increased from 48 in the 13 years before installation of phones to 106 the following 13 years or by 4.5 additional suicides/year (t =3.512, p < .001). Conclusion: Although the phones prevented some suicides, there was a net increase after installation. The findings are interpreted with reference to suggestion/contagion effects including the emergence of a controversial bridge suicide blog.

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