The greater Agulhas Current region is an important component of the climate system, yet its influence on carbon and nutrient cycling poorly understood. Here, we use nitrate isotopes (δ15N, δ18O, Δ(15–18) = δ15N–δ18O) to trace regional water mass circulation investigate nitrogen in adjacent recirculating waters. deep intermediate waters record processes occurring remotely, including partial assi...

Understanding the relationships between carbon; nitrogen, their stable isotopes δ13C and δ15N, soil stoichiometry may further our understanding of regulatory mechanisms quality index on equilibrium isotopic fractionation. Four plantations Zanthoxylum planispinum var. dintanensis (5–7, 10–12, 20–22 30–32 years) in karst plateau gorge area, Guizhou Province, China, were selected to determine vari...

Natural dietary markers (stable isotopes and fatty acids) were used to determine the trophic structure and characterize carbon source(s) of juvenile and adult fishes associated with floating Sargassum in mid-shelf waters of the Gulf of Mexico. Stable carbon isotope ratios (δ13C) of 4 autotrophs (Cladophora sp., phytoplankton [based on particulate organic matter, POM], S. fluitans, S. natans) we...

We investigated the food web structure of the Salses-Leucate Lagoon (northwestern Mediterranean) through δ13C and δ15N analysis of its benthic macrofauna and potential food sources. This lagoon was heavily human-modified during the 1970s, allowing permanent exchange with the open sea and an increase in salinity from that time. As a result, it exhibits a much less marked salinity gradient than t...

The bioaccumulation and biomagnification of mercury (Hg) and selenium (Se) were investigated in sub-tropical freshwater food webs from Burkina Faso, West Africa, a region where very few ecosystem studies on contaminants have been performed. During the 2010 rainy season, samples of water, sediment, fish, zooplankton, and mollusks were collected from three water reservoirs and analysed for total ...

Understanding reproductive rates of wild animal populations is crucially important for management and conservation. Assessing pregnancy status of free-ranging cetaceans has historically been difficult; however, recent advances in analytical techniques have allowed the diagnosis of pregnancy from small samples of blubber tissue. The primary objectives of this study were as follows: (i) to test t...

Migratory patterns of bats are not well understood and traditional methods to study this, like capture-mark-recapture, may not provide enough detail unless there are many records. Stable isotope profiles of many animal species have been used to make inferences about migration. Each year Myotis lucifugus and M. septentrionalis migrate from summering roosts to swarming caves and mines in the fall...

According to the refugee species concept, increasing replacement of open steppe by forest cover after the last glacial period and human pressure had together forced European bison (Bison bonasus)--the largest extant terrestrial mammal of Europe--into forests as a refuge habitat. The consequent decreased fitness and population density led to the gradual extinction of the species. Understanding t...

The influence of global warming on soil organic matter (SOM) dynamics in terrestrial ecosystems remains unclear. In this study, we combined soil fractionation with isotope analyses to examine SOM dynamics after nine years of experimental warming in a North America tallgrass prairie. Soil samples from the control plots and the warmed plots were separated into four aggregate sizes (>2000 μm, 250–...