10 research outputs found
New Petro‐aggression in the Middle East: Saudi Arabia in the Spotlight
That hydrocarbon abundance may lead to more violence is an established truism in the literature on the resource curse. Looking at the Middle East, however, the literature relates bellicose state behaviour entirely to oil-producing revolutionary republics. Instead, dynastic monarchies are claimed to be the more peacefully behaving actors. Current developments turn this conclusion upside down, however. Since 2015 at the latest, the foreign policy of Saudi Arabia, the leading monarchy in the Middle East, has transformed from multi-dependence to petro-aggression. By discussing this striking transformation, the paper puts forward a framework looking at the interaction of three crucial dimensions: first, the decreasing power projection towards the Middle East by the United States, the decade-long hegemon, due to gradual changes in world energy markets and war fatigue at home; second, the lasting fiscal potency of the Saudi regime; and, third, the personalization of the Saudi monarchy under King Salman as a historically contingent result of transferring power to the generation of Ibn Saud's grandsons
Impact of the 1993 Flood on the Distribution of Organic Contaminants in Bed Sediments of the Upper Mississippi River
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Corrigendum: The role of precipitation type, intensity, and spatial distribution in source water quality after wildfire (2015 Environ. Res. Lett. 10 084007)
Storms following wildfires are known to impair drinking water supplies in the southwestern United States, yet our understanding of the role of precipitation in post-wildfire water quality is far from complete. We quantitatively assessed water-quality impacts of different hydrologic events in the Colorado Front Range and found that for a three-year period, substantial hydrologic and geochemical responses downstream of a burned area were primarily driven by convective storms with a 30 min rainfall intensity >10 mm h-1 . These storms, which typically occur several times each year in July–September, are often small in area, short-lived, and highly variable in intensity and geographic distribution. Thus, a rain gage network with high temporal resolution and spatial density, together with high-resolution stream sampling, are required to adequately characterize post-wildfire responses. We measured total suspended sediment, dissolved organic carbon (DOC), nitrate, and manganese concentrations that were 10–156 times higher downstream of a burned area compared to upstream during relatively common (50% annual exceedance probability) rainstorms, and water quality was sufficiently impaired to pose water-treatment concerns. Short-term water-quality impairment was driven primarily by increased surface runoff during higher intensity convective storms that caused erosion in the burned area and transport of sediment and chemical constituents to streams. Annual sediment yields downstream of the burned area were controlled by storm events and subsequent remobilization, whereas DOC yields were closely linked to annual runoff and thus were more dependent on interannual variation in spring runoff. Nitrate yields were highest in the third year post-wildfire. Results from this study quantitatively demonstrate that water quality can be altered for several years after wildfire. Because the southwestern US is prone to wildfires and high-intensity rain storms, the role of storms in post-wildfire water-quality impacts must be considered when assessing water-quality vulnerability.</p
Fate of 4-Nonylphenol and 17β-Estradiol in the Redwood River of Minnesota
The majority of previous research investigating the fate of endocrine-disrupting
compounds has focused on single processes generally in controlled
laboratory experiments, and limited studies have directly evaluated
their fate and transport in rivers. This study evaluated the fate
and transport of 4-nonylphenol, 17β-estradiol, and estrone in
a 10-km reach of the Redwood River in southwestern Minnesota. The
same parcel of water was sampled as it moved downstream, integrating
chemical transformation and hydrologic processes. The conservative
tracer bromide was used to track the parcel of water being sampled,
and the change in mass of the target compounds relative to bromide
was determined at two locations downstream from a wastewater treatment
plant effluent outfall. In-stream attenuation coefficients (<i>k</i><sub>stream</sub>) were calculated by assuming first-order
kinetics (negative values correspond to attenuation, whereas positive
values indicate production). Attenuation of 17β-estradiol (<i>k</i><sub>stream</sub> = −3.2 ± 1.0 day<sup>–1</sup>) was attributed primarily due to sorption and biodegradation by
the stream biofilm and bed sediments. Estrone (<i>k</i><sub>stream</sub> = 0.6 ± 0.8 day<sup>–1</sup>) and 4-nonylphenol
(<i>k</i><sub>stream</sub> = 1.4 ± 1.9 day<sup>–1</sup>) were produced in the evaluated 10-km reach, likely due to biochemical
transformation from parent compounds (17β-estradiol, 4-nonylphenolpolyethoxylates,
and 4-nonyphenolpolyethoxycarboxylates). Despite attenuation, these
compounds were transported kilometers downstream, and thus additive
concentrations from multiple sources and transformation of parent
compounds into degradates having estrogenic activity can explain their
environmental persistence and widespread observations of biological
disruption in surface waters
In-Stream Attenuation of Neuro-Active Pharmaceuticals and Their Metabolites
In-stream
attenuation was determined for 14 neuro-active pharmaceuticals
and associated metabolites. Lagrangian sampling, which follows a parcel
of water as it moves downstream, was used to link hydrological and
chemical transformation processes. Wastewater loading of neuro-active
compounds varied considerably over a span of several hours, and thus
a sampling regime was used to verify that the Lagrangian parcel was
being sampled and a mechanism was developed to correct measured concentrations
if it was not. In-stream attenuation over the 5.4-km evaluated reach
could be modeled as pseudo-first-order decay for 11 of the 14 evaluated
neuro-active pharmaceutical compounds, illustrating the capacity of
streams to reduce conveyance of neuro-active compounds downstream.
Fluoxetine and <i>N</i>-desmethyl citalopram were the most
rapidly attenuated compounds (<i>t</i><sub>1/2</sub> = 3.6
± 0.3 h, 4.0 ± 0.2 h, respectively). Lamotrigine, 10,11,-dihydro-10,11,-dihydroxy-carbamazepine,
and carbamazepine were the most persistent (<i>t</i><sub>1/2</sub> = 12 ± 2.0 h, 12 ± 2.6 h, 21 ± 4.5 h, respectively).
Parent compounds (e.g., buproprion, carbamazepine, lamotrigine) generally
were more persistent relative to their metabolites. Several compounds
(citalopram, venlafaxine, <i>O</i>-desmethyl-venlafaxine)
were not attenuated. It was postulated that the primary mechanism
of removal for these compounds was interaction with bed sediments
and stream biofilms, based on measured concentrations in stream biofilms
and a column experiment using stream sediments