scholarly journals Legacy Lead from Past Mining Activity and Gasoline Additives: Evidence from Lead Isotopes and Trace Element Geochemical Studies in the White River Basin, Southern Ozark Region, USA

Geosciences ◽  
2018 ◽  
Vol 8 (6) ◽  
pp. 189 ◽  
Author(s):  
Adriana Potra ◽  
Laura Ruhl ◽  
John Samuelsen
2021 ◽  
Author(s):  
Yangyang Wang ◽  
Wu Ma ◽  
Lenny D Farlee ◽  
Elizabeth A Jackson ◽  
Guofan Shao ◽  
...  

Abstract Stand improvement (SI) has been widely accepted as an effective forest management tool. Yet most studies on its economic feasibility for nonindustrial private forest (NIPF) landowners are outdated and focus on the single stand level. The objective of this study was to conduct an economic assessment of SI’s effects and feasibility in hardwood stands for a case study in the White River Basin in Indiana. It is shown that SI could make these forests more productive and sustainable than the prevalent “hands-off” practice by enhancing the timber value of the residual stand (TV), generating regular timber income, and to some degree, reversing the decline in oak dominance. On average, a 25% increment in the TV could be achieved. Although costly for some NIPFs, once combined with voluntary financial incentive programs, SI could meet landowners’ demands for low-cost, high-return investment options. In particular, participation in the Environmental Quality Incentive Program could, on average, increase the net present value of timber income from thinning activities by nearly $1,600 per hectare over the course of 30 years. The spatial analysis revealed that there existed considerable spatial heterogeneity in SI benefits and impacts, suggesting that public incentive programs should be spatially targeted to achieve greater efficiency. Study Implications This study found that stand improvement (SI) could significantly improve the timber value of forestland in the central hardwood region. Participation in voluntary conservation programs, such as the Environmental Quality Incentive Program, could alleviate part of the SI cost thus making it an attractive investment opportunity for private landowners. For the study region, the White River Basin in Indiana, the results suggested that there existed substantial variations in SI’s effectiveness across space. This implied that program administrators of voluntary incentives could improve the efficiency of public funds allocation by considering this spatial variation when evaluating landowners’ applications for incentives.


2010 ◽  
Vol 11 (1) ◽  
pp. 122-138 ◽  
Author(s):  
Guoxiang Yang ◽  
Laura C. Bowling ◽  
Keith A. Cherkauer ◽  
Bryan C. Pijanowski ◽  
Dev Niyogi

Abstract Impervious surface area (ISA) has different surface characteristics from the natural land cover and has great influence on watershed hydrology. To assess the urbanization effects on streamflow regimes, the authors analyzed the U.S. Geological Survey (USGS) streamflow data of 16 small watersheds in the White River [Indiana (IN)] basin. Correlation between hydrologic metrics (flow distribution, daily variation in streamflow, and frequency of high-flow events) and ISA was investigated by employing the nonparametric Mann–Kendall method. Results derived from the 16 watersheds show that urban intensity has a significant effect on all three hydrologic metrics. The Variable Infiltration Capacity (VIC) model was modified to represent ISA in urbanized basins using a bulk parameterization approach. The model was then applied to the White River basin to investigate the potential ability to simulate the water and energy cycle response to urbanization. Correlation analysis for individual VIC grid cells indicates that the VIC urban model was able to reproduce the slope magnitude and mean value of the USGS streamflow metrics. The urban model also reproduced the urban heat island (UHI) seen in the Moderate Resolution Imaging Spectroradiometer (MODIS) land surface temperature products, especially for the grids encompassing the city of Indianapolis, IN. The difference of the hydrologic metrics obtained from the VIC model with and without urban representation indicates that the streamflow regime in the White River has been modified because of urban development. The observed data, together with model analysis, suggested that 3%–5% ISA in a watershed is the detectable threshold, beyond which urbanization effects start to have a statistically significant influence on streamflow regime.


1975 ◽  
Vol 12 (3) ◽  
pp. 361-370 ◽  
Author(s):  
Jackson M. Barton Jr. ◽  
Erika S. Barton

The Snyder breccia is composed of angular to subrounded xenoliths of migmatites and amphibolites in a very fine grained matrix. It is apparently intrusive into the metasediments of the Snyder Group exposed at Snyder Bay, Labrador. The Snyder Group unconformably overlies a migmatitic and amphibolitic basement complex and is intruded by the Kiglapait layered intrusion. K–Ar ages indicate that the basement complex is Archean in age (> 2600 m.y. old) and that the Kiglapait layered intrusion was emplaced prior to 1280 m.y. ago. Major and trace element analyses of the matrix of the Snyder breccia indicate that while it was originally of tonalitic composition, later it locally underwent alteration characterized by loss of sodium and strontium and gain of potassium, rubidium and barium. Rb–Sr isotopic analyses show that this alteration occurred about 1842 m.y. ago, most probably contemporaneously with emplacement of the breccia. The Snyder Group thus was deposited sometime between 2600 and 1842 m.y. ago and may be correlative with other Aphebian successions preserved on the North Atlantic Archean craton.


2020 ◽  
Vol 2 (8) ◽  
Author(s):  
Dharmendra Kumar Jigyasu ◽  
Munendra Singh ◽  
Sandeep Singh ◽  
Satyendra Singh ◽  
Indra Bir Singh

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