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Watershed-scale impacts of stormwater green infrastructure on hydrology, nutrient fluxes, and combined sewer overflows in the mid-Atlantic region
AbstractStormwater green infrastructure (SGI), including rain gardens, detention ponds, bioswales, and green roofs, is being implemented in cities across the globe to reduce flooding, combined sewer overflows, and pollutant transport to streams and rivers. Despite the increasing use of urban SGI, few studies have quantified the cumulative effects of multiple SGI projects on hydrology and water quality at the watershed scale. To assess the effects of SGI, Washington, DC, Montgomery County, MD, and Baltimore County, MD, were selected based on the availability of data on SGI, water quality, and stream flow. The cumulative impact of SGI was evaluated over space and time by comparing watersheds with and without SGI, and by assessing how long-term changes in SGI impact hydrologic and water quality metrics over time. Most Mid-Atlantic municipalities have a goal of achieving 10â20% of the landscape drain runoff through SGI by 2030. Of these areas, Washington, DC currently has the greatest amount of SGI (12.7% of the landscape drained through SGI), while Baltimore County has the lowest (7.9%). When controlling for watersheds size and percent impervious surface cover, watersheds with greater amounts of SGI have less flashy hydrology, with 44% lower peak runoff, 26% less frequent runoff events, and 26% less variable runoff. Watersheds with more SGI also show 44% less NO3â and 48% less total nitrogen exports compared to watersheds with minimal SGI. There was no significant reduction in phosphorus exports or combined sewer overflows in watersheds with greater SGI. When comparing individual watersheds over time, increases in SGI corresponded to non-significant reductions in hydrologic flashiness compared to watersheds with no change in SGI. While the implementation of SGI is somewhat in its infancy in some regions, cities are beginning to have a scale of SGI where there are statistically significant differences in hydrologic patterns and water quality
A competitive cell-permeable peptide impairs Nme-1 (NDPK-A) and Prune-1 interaction: therapeutic applications in cancer.
The understanding of proteinâprotein interactions is crucial in order to generate a second level of functional genomic analysis in human disease. Within a cellular microenvironment, proteinâprotein interactions generate new functions that can be defined by single or multiple modes of protein interactions. We outline here the clinical importance of targeting of the Nme-1 (NDPK-A)âPrune-1 protein complex in cancer, where an imbalance in the formation of this proteinâprotein complex can result in inhibition of tumor progression. We discuss here recent functional data using a small synthetic competitive cell-permeable peptide (CPP) that has shown therapeutic efficacy for impairing formation of the Nme-1âPrune-1 protein complex in mouse preclinical xenograft tumor models (e.g., breast, prostate, colon, and neuroblastoma). We thus believe that further discoveries in the near future related to the identification of new proteinâprotein interactions will have great impact on the development of new therapeutic strategies against various cancers
Effects of vessel traffic on relative abundance and behaviour of cetaceans : the case of the bottlenose dolphins in the Archipelago de La Maddalena, north-western Mediterranean sea
Acknowledgements This study was part of the Tursiops Project of the Dolphin Research Centre of Caprera, La Maddalena. Financial and logistical support was provided by the Centro Turistico Studentesco (CTS) and by the National Park of the Archipelago de La Maddalena. We thank the Natural Reserve of Bocche di Bonifacio for the support provided during data collection. The authors thank the numerous volunteers of the Caprera Dolphin Research Centre and especially Marco Ferraro, Mirko Ugo, Angela Pira and Maurizio Piras whose assistance during field observation and skills as a boat driver were invaluable.Peer reviewedPostprin
Influence of infrastructure on water quality and greenhouse gas dynamics in urban streams
Streams and rivers are significant sources of nitrous oxide
(N2O), carbon dioxide (CO2), and methane (CH4) globally, and
watershed management can alter greenhouse gas (GHG) emissions from streams.
We hypothesized that urban infrastructure significantly alters downstream
water quality and contributes to variability in GHG saturation and emissions.
We measured gas saturation and estimated emission rates in headwaters of two
urban stream networks (Red Run and Dead Run) of the Baltimore Ecosystem Study
Long-Term Ecological Research
project. We identified four combinations of
stormwater and sanitary infrastructure present in these watersheds,
including: (1)Â stream burial, (2)Â inline stormwater wetlands, (3)Â riparian/floodplain preservation, and (4)Â septic systems. We selected two first-order
catchments in each of these categories and measured GHG concentrations,
emissions, and dissolved inorganic and organic carbon (DIC and DOC) and nutrient
concentrations biweekly for 1Â year. From a water quality perspective, the
DOCâŻ:âŻNO3â ratio of streamwater was significantly different across
infrastructure categories. Multiple linear regressions including DOCâŻ:âŻNO3â and other variables (dissolved oxygen, DO; total dissolved nitrogen, TDN;
and temperature) explained much of
the statistical variation in nitrous oxide (N2O, r2â=ââŻ0.78), carbon
dioxide (CO2, r2â=ââŻ0.78), and methane (CH4, r2â=ââŻ0.50)
saturation in stream water. We measured N2O saturation ratios, which
were among the highest reported in the literature for streams, ranging from
1.1 to 47 across all sites and dates. N2O saturation ratios were highest
in streams draining watersheds with septic systems and strongly correlated
with TDN. The CO2 saturation ratio was highly correlated with the N2O
saturation ratio across all sites and dates, and the CO2 saturation ratio
ranged from 1.1 to 73. CH4 was always supersaturated, with saturation
ratios ranging from 3.0 to 2157. Longitudinal surveys extending form
headwaters to third-order outlets of Red Run and Dead Run took place in
spring and fall. Linear regressions of these data yielded significant negative
relationships between each gas with increasing watershed size as well as
consistent relationships between solutes (TDN or DOC, and DOCâŻ:âŻTDN ratio) and
gas saturation. Despite a decline in gas saturation between the headwaters
and stream outlet, streams remained saturated with GHGs throughout the
drainage network, suggesting that urban streams are continuous sources of
CO2, CH4, and N2O. Our results suggest that infrastructure
decisions can have significant effects on downstream water quality and
greenhouse gases, and watershed management strategies may need to consider
coupled impacts on urban water and air quality
STRATIGRAPHIC AND STRUCTURAL ANALYSIS OF A HIGH RESOLUTION SEISMIC SURVEY PERFORMED IN THE BAY OF AUGUSTA (SE SICILY)
The Bay of Augusta is located along the NE margin of the Hyblean Plateau (SE Sicily). In this area a mostly
bioclastic and terrigenous Quaternary succession outcrops. This area recorded a constant regional uplift rate
of <1 mm/yr during the Late Pleistocene and recurrent, strong (up to 7.0 Md) historical earthquakes.
Data for this study come from a recent nearshore geophysical survey performed by URS Corporation Ltd with
the aim to evaluate the potential for seismic hazard. The collected data consist of: 1) a high resolution seismic
survey (sparker source and sub-bottom profiling); 2) five soil borings to characterize and obtain age dates for
shallow subsea sediments.
Four main seismic units have been recognized inside the sedimentary infill:
âą Unit D is the oldest, seawards dipping, unit overlying the acoustic basement. Upwards this unit is bounded
by a rough, erosional truncation (horizon H4).
âą Unit C shows sub-horizontal reflectors with variable seismic attributes, forming a prominent angular
unconformity above H4; in the proximal sector of the Augusta Bay they lie seaward dipping. This unit shows
valuable thickness change across the Bay and is bounded upwards by a very rough erosional truncation
(horizon H3).
âą Unit B shows planar parallel reflectors with good lateral continuity. Its thickness change and it is very thin
along the slope of the morphostructural highs formed by uplift of units D and C. Upwards it is bounded by a
very prominent erosional truncation (H2 horizon).
âą Unit A is imaged by sub-horizontal, continuous reflectors, alternating with intervals of transparent seismic
facies. The reflectors onlap the H2 horizon and, in a few places, display prograding geometry.
On the collected samples biochronological and radiometric age-dating has been performed. The cores drilled
the unit A and the uppermost part of the unit B, where the sediments have revealed absolute age > 50 kA.
Two main groups of faults, referred to as the northwest and the southwest fault zones, are separated by a
central zone where no evident fault planes have been imaged by seismic data. The faults in both groups strike
from N30W to N52W and are also inferred to be steeply dipping.
The faults pertaining to northwestern cluster show a very little offset, < 15 m. These faults have displaced
mostly seismic unit C and have controlled two, NW-SE trending little structural lows in the central and in the
northernmost sectors of the investigated area. These restricted basins have been filled by B and A seismic
units deposits that donât appear displaced by the fault cluster.
The southeastern fault zone is long less than 700 m and show an offset of 1 to 5 m. These faults displaced the
horizons of seismic Unit C in a sector where this unit outcrops at the sea bottom or it is draped by a very thin
veneer of Unit A sediments.
The faults pertaining to the northwestern zone post-date Unit C but they appear older than Units B and A.Radiocarbon age-dating have demonstrated that the most recent horizons involved in the northwestern fault
zone displacement is > 50 kA.
As concern the southeastern fault zone, results coming from radiocarbon age dating donât have sufficient
resolution to correlate deposits to seismic horizons involved in tectonic deformation. Nevertheless, there the
seismic unit A also appears slightly involved by the latest faults activity.
The analysis of the Bay of Augusta seismic grid has shown that very recent tectonic features have displaced
the Late Quaternary sedimentary infill; interpretation of our results could better constrain the neotectonic
setting of an area characterized by high seismic hazard
Oxo-centered carboxylate-bridged trinuclear complexes deposited on Au(111) by a mass-selective electrospray.
We developed an apparatus for nondestructive in vacuum deposition of mass-selected fragile Cr based metal trinuclear complexes, by modifying a commercial Mass Spectrometer containing an electrospray ionization source. Starting from a solution, this system creates a beam of ionized molecules which is then transferred into an evacuated region where the molecules can be mass selected before deposition. To verify the system efficiency, we deposited sub monolayers of oxo-centered carboxylate-bridged trinuclear complexes (Cr3 and Cr2Ni) on Au(111) surface. By XPS and STM we determined the deposited molecule stoichiometry and the surface coverage. The results show that this apparatus is works well for the in vacuum deposition of molecular nanomagnets and, thanks to its reduced dimensions, it is portable
Historical summer distribution of the endangered North Atlantic right whale (Eubalaena glacialis): a hypothesis based on environmental preferences of a congeneric species
Aim: To obtain a plausible hypothesis for the historical distribution of North Atlantic right whales (NARWs) (Eubalaena glacialis) in their summer feeding grounds. Previously widespread in the North Atlantic, after centuries of hunt- ing, these whales survive as a small population off eastern North America. Because their exploitation began before formal records started, information about their historical distribution is fragmentary
On the Role of Perception: Understanding Stakeholdersâ Collaboration in Natural Resources Management through the Evolutionary Theory of Innovation
Natural resources management deals with highly complex socioecological systems. This
complexity raises a conundrum, since wide-ranging knowledge from different sources and types
is needed, but at the same time none of these types of knowledge is able by itself to provide
the basis for a viable productive system, and mismatches between the two of them are common.
Therefore, a growing body of literature has examined the integration of different types of knowledge
in fisheries management. In this paper, we aim to contribute to this ongoing debate by integrating
the evolutionary theory of innovationâand specifically the concept of proximityâand the theory of
perception. We set up a theoretical framework that is able to explain not only why the different types
of knowledge differ, but also why they should differ and why this divergence is useful to develop
fisheries management. This framework is illustrated through a well-known complex scenario, as was
the implementation of the Landing Obligation (LO) in Europe. We conclude that diversity (distance)
between types of knowledge is essential for interactive learning, innovation, the incorporation of new
ideas or to avoid lock-in, etc. At the same time, cognitive, institutional, geographical, etc. proximity
is needed for effective communication, participation and dialoguePostprin
Integrating spatial management measures into fisheries: The Lepidorhombus spp. case study
Most fisheries management systems rely on a set of regulatory measures to achieve desired objectives. Controls
on catch and effort are usually supplemented with gear restrictions, minimum landing sizes, and in the framework of the new common fisheries policy, limitation of discards and by-catch. However, the increasing use of
spatial management measures such as conservation areas or spatial and temporal area closures faces new
challenges for fishery managers. Here we present an integrated spatial framework to identify areas in which
undersized commercial species are more abundant. Once these areas are identified they could be avoided by
fishers, minimizing the fishing impact over the immature fraction of the stocks. In particular we applied this
methodology to two species of megrim, Lepidorhombus whiffiagonis and L. boscii, in North Atlantic Iberian waters
(ICES Divisions 8c and 9a), analyzing fishery-independent data provided by bottom-trawl surveys and environmental data through Bayesian spatial models. Results show that species exhibit species-specific spatial patterns, and we identified sensitive areas that could be used for conservation purposes. We discuss integrating
technical measures together (e.g. Minimum Conservation Reference Size and spatial closures) could be a more
effective approach for fishery management and this case study could be extended to other species.Postprint1,86
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