Nitrate contamination in rivers has raised widespread concern in the world, particularly in arid/semi-arid river basins lacking qualified water. Understanding the nitrate pollution levels and sources is critical to control the nitrogen input and promote a more sustainable water management in those basins. Water samples were collected from a typical semi-arid river basin, the Weihe River watersh...

Wildfires can significantly alter forest carbon (C) storage and nitrogen (N) availability, but the long-term biogeochemical legacy of wildfires is poorly understood. We obtained a lake-sediment record of fire and biogeochemistry from a subalpine forest in Colorado, USA, to examine the nature, magnitude, and duration of decadal-scale, fire-induced ecosystem change over the past c. 4250 yr. The h...

Organochlorine compounds (OCs), brominated flame retardants (BFRs) and stable isotopes (δ15N and δ13C) were analyzed in various deep-sea organisms collected from Sagami Bay, Japan in 2004. PCBs and DDTs were the predominant contaminants detected in this study, followed by CHLs > HCB > HBCDs > PBDEs > HCHs. Concentrations of PCBs, DDTs, CHLs, HCB and PBDEs, which have high adsorptive affinities ...

Studies in freshwater ecosystems are seeking to improve understanding of carbon flow in food webs and stable isotopes have been influential in this work. However, variation in isotopic values of basal production sources could either be an asset or a hindrance depending on study objectives. We assessed the potential for basin geology and local limnological conditions to predict stable carbon and...

Soils are capable to consume N2O. It is generally assumed that consumption occurs exclusively via respiratory reduction to N2 by denitrifying organisms (i.e. complete denitrification). Yet, we are not aware of any verification of this assumption. Some N2O may be assimilatorily reduced to NH3. Reduction of N2O to NH3 is thermodynamically advantageous compared to the reduction of N2. Is this an e...

Ratios of stable isotopes in feathers have great potential for identifying the connectivity of bird migrations and the origin of harvested individuals of game species. In particular, the relationship between the hydrogen ratio due to latitudinal variation in precipitation (δDp) and that in feathers (δDf) is often used to determine unknown individuals’ latitude of origin. We assessed this relati...

The nutritional state of animals is tightly linked to the ambient environment, and for northern ungulates the state strongly influences vital population demographics, such as pregnancy rates. Continuously growing tissues, such as hair, can be viewed as dietary records of animals over longer temporal scales. Using sequential data on nitrogen stable isotopes (δ15N) in muskox guard hairs from ten ...

The biomass dynamics of primary producers have important implications for the structure and function of ecosystems. Along the wave-swept coastline of central California, USA, biomass removal by wave action is a key driver in the primary productivity of giant kelp forests, yet the mechanisms of regrowth within giant kelp Macrocystis pyrifera are not well understood. To examine the physiological ...

Stable isotope measurements are increasingly being used to gain insights into the nutritional ecology of many wildlife species and their role in ecosystem structure and function. Such studies require estimations of trophic discrimination factors (i.e. differences in the isotopic ratio between the consumer and its diet). Although trophic discrimination factors are tissue- and species-specific, r...

While breeding, seabirds are limited to exploiting resources within a restricted area around their breeding site and should exploit the closest productive marine areas within their distribution range. We investigated this hypothesis in one of the most endangered European seabirds, the Balearic shearwater Puffinus mauretanicus (ca. 3200 breeding pairs), restricted to the Balearic Islands. Our ai...