Treesearch

Silver nanoparticles (Ag NPs) are widely used in consumer products, and their release has raised serious concerns about the risk of their exposure to the environment and to human health. However, biochemical mechanisms by which plants counteract NP toxicity are largely unknown. We have previously engineered Crambe abyssinica plants expressing the bacterial γ-glutamylecysteine synthase (y-ECS) for enhancing glutathione (GSH) levels. In this study, we investigated if enhanced levels of GSH and its derivatives can protect plants from Ag NPs and AgNO3 (Ag+ ions). Our results showed that...

Dam removal is reconnecting rivers, and lessons learned will help water-resource and river management, particularly as removals expand globally and choices become more challenging.

Empirical and dynamic biogeochemical modelling are complementary approaches for determining the critical load (CL) of atmospheric nitrogen (N) or other constituent deposition that an ecosystem can tolerate without causing ecological harm. The greatest benefits are obtained when these approaches are used in combination. Confounding environmental factors can complicate the determination of empirical CLs across depositional gradients, while the experimental application of N amendments for estimating the CL does not realistically mimic the effects of chronic atmospheric N deposition. Biogeochem...

Atmospheric deposition in the Athabasca Oil Sands Region decreased exponentially with distance from the industrial center. Throughfall deposition (kg ha−1 yr−1) of NH4–N (.8–14.7) was double that of NO3–N (.3–6.7), while SO4–S ranged from 2.5 to 23.7. Gaseous pollutants (NO2, HNO3, NH3, SO2) are important drivers of atmospheric deposition but weak correlations between gaseous pollutants and deposition suggest that particulate deposition is also important. The deposition (eq ha−1) of base cations (Ca + Mg + Na) across the sampling network was highly similar to N + S deposition, suggesting...

Lakes and streams in Class 1 wilderness areas in the western United States (U.S.) are at risk from atmospheric deposition of nitrogen (N) and sulfur (S), and protection of these resources is mandated under the Federal Clean Air Act and amendments. Assessment of critical loads, which are the maximum exposure to pollution an area can receive without adverse effects on sensitive ecosystems, requires accurate deposition estimates. However, deposition is difficult and expensive to measure in high-elevation wilderness, and spatial patterns in N and S deposition in these areas remain poorly...

Determining the detailed movements of individual animals often requires them to carry tracking devices, but tracking broad-scale movement of small bats (<30 g) has been limited by transmitter technology and long-term attachment methods. This limitation inhibits our understanding of bat dispersal and migration, particularly in the context of emerging conservation issues such as fatalities at wind turbines and diseases. We tested a novel method of attaching lightweight global positioning system (GPS) tags and geolocating data loggers to small bats. We used monofilament, synthetic, absorbable...

Highlights •The new residential and renovation construction markets in the US and the Eurozone were valued at $338.7 billion (305.5 billion euros) and $673.3 billion dollars (614.4 billion euros), respectively, in 2014. •In Europe, 55% of the value of the new residential and renovation construction markets in 2014 was in renovation; in the US, this figure was 30%. •The housing construction market in Europe is still subdued, in part due to the effects of the global financial crisis and the tepid nature of European economies. Nevertheless, residential housing construction is projected to...

Fire history studies are important tools for understanding past fire regimes and the roles humans played in those regimes. Beginning in 2010, we conducted a fire history study in the Pine Creek Gorge area of north-central Pennsylvania to ascertain the number of fires and fire-free intervals, their variability through time, and the role of human influences. We collected 93 cross sections from fire-scarred red pine (Pinus resinosa) snags, stumps, and living trees at three separate sites along the western rim of Pine Creek Gorge. From these, we found 79 fire years and 11 multidecadal fire-free...

Long-term monitoring programs that can detect a population change over time can be useful for managers interested in assessing population trends in response to forest management activities for a particular species. Such long-term monitoring programs have been designed for the Northern Goshawk (Accipiter gentilis), but not for the more elusive Sharp-shinned (A. striatus) and Cooper's hawks (A. cooperii). The objectives of this study were to (1) determine if it was possible to survey for these two Accipiters at the same time successfully using a new survey technique, and (2) estimate...

Resting habitat used by fishers (Pekania pennanti) has been relatively well studied but information on the persistence of their resting structures over time is unknown. We selected for reexamination 73 of 195 resting structures used by by fishers in northwestern California and compared their condition on the date they were found with their condition 8.2–12.1 years later. Resting structures were classified into three functional groups: live trees, snags, and logs. Each group was classified further into structural stages of decay or decomposition. A total of 19.2% of resting structures...