The processes of natural ecosystems are strongly affected by the lifestyles of their most numerous inhabitants, the bacterial and archaeal prokaryotes. Examples of phenomena that affect local ecosystems and the biosphere at large include cycling of carbon and nitrogen, and both positive and negative interactions with plants and animals. Recent advances in molecular techniques such as 16S rDNA s...

The oceans are becoming more acidic due to absorption of anthropogenic carbon dioxide from the atmosphere. The impact of ocean acidification on marine ecosystems is unclear, but it will likely depend on species adaptability and the rate of change of seawater pH relative to its natural variability. To constrain the natural variability in reef-water pH, we measured boron isotopic compositions in ...

Humankind has dramatically transformed much of the Earth’s surface and its natural ecosystems. This process is not new—it has been ongoing for millennia—but it has accelerated sharply over the last two centuries, and especially in the last several decades. Today, the loss and degradation of natural habitats can be likened to a war of attrition. Many natural ecosystems are being progressively ra...

Anammox (anaerobic ammonium oxidation), which is a reaction that oxidizes ammonium to dinitrogen gas using nitrite as the electron acceptor under anoxic conditions, was an important discovery in the nitrogen cycle. The reaction is mediated by a specialized group of planctomycete-like bacteria that were first discovered in man-made ecosystems. Subsequently, many studies have reported on the ubiq...

Perchlorate (Cl4-) reservoirs that accumulated in semiarid unsaturated zones, similar to chloride (Cl-), can contaminate underlying aquifers if they are mobilized. The purpose of this study was to evaluate Cl)4- mobilization related to land-use change from natural to agricultural ecosystems in the southern High Plains (SHP, USA), where large ClO4- concentrations (< or =60 microg/L) are found in...

Habitat complexity is a major determinant of structure and diversity of ant assemblages. Following the size-grain hypothesis, smaller ant species are likely to be advantaged in more complex habitats compared to larger species. Habitat complexity can act as an environmental filter based on species size and morphological traits, therefore affecting the overall structure and diversity of ant assem...

Millennia of human land-use have resulted in the widespread occurrence of what have been coined 'domesticated ecosystems'. The anthropogenic imprints on diversity, composition, structure and functioning of such systems are well documented. However, evolutionary consequences of human activities in these ecosystems are enigmatic. Calluna vulgaris (L.) is a keystone species of coastal heathlands i...

Riverine ecosystems have been altered in many large catchments by dam development to provide water, power, flood control and navigational benefits to humans. Conservation actions in these river ecosystems are commonly focused on minimum releases of water to downstream ecosystems. Increasingly minimum release approaches are being replaced with ‘experimental’ flows that mimic natural conditions i...