Nutrient cycling is a ubiquitous feature of ecosystems at all scales, allowing productivity to rise beyond the limits set by external nutrient inputs. Nutrient cycling occurs as a side-effect of the metabolism of a diverse set of species that each performs a step in the recycling loop. Recycling loops can be large and involve many steps. At each step the possibility exists for ‘side-reactions’ ...

Over much of the ocean’s surface, productivity and growth are limited by a scarcity of bioavailable nitrogen. Sedimentary 15N records spanning the last deglaciation suggest marked shifts in the nitrogen cycle during this time, but the quantification of these changes has been hindered by the complexity of nitrogen isotope cycling. Herewepresent a database of 15N in sediments throughout the world...

Jones, J.R., M.F. Knowlton and D.V. Obrecht. 2008. Role of land cover and hydrology in determining nutrients in mid-continent reservoirs: implications for nutrient criteria and management. Lake Reserv. Manage. 24:1−9. Effects of nutrient input, hydraulic flushing rate and depth on reservoir nutrients were examined in the mid-continent landscape of the Ozark Highlands and Plains in Missouri and ...

BACKGROUND Dairy products are important in a healthy diet due to their high nutritional value; they are, however, associated with relatively large greenhouse gas emissions (GHGE) per kg product. When discussing the need to reduce the GHGE caused by the food system, it is crucial to consider the nutritional value of alternative food choices. OBJECTIVE The objective of this study was to elucida...

The emergence of third-generation, technology-based public bikeshare schemes offers new opportunities for researching cycling behaviour. In this study, data from one such scheme, the London Cycle Hire Scheme (LCHS), are analysed. Algorithms are developed for summarising and labelling cyclists’ usage behaviours and tailored visual analysis applications are designed for exploring their spatiotemp...

Introduction Conclusions References

The increasing reduction of wetlands such as riparian areas is regarded as a serious loss due to their high ecological value. A growing need for the assessment of wetland values and the beneficial ecosystem services they provide is noted. An overview of recent studies using different approaches to assign monetary values to different valuable functions is given. In a case study of the river Elbe...

In 1998, we measured the effects of Hurricane Georges after it passed over long-term research sites in Puerto Rican dry forest. Our primary objectives were to quantify hurricane effects on forest structure, to compare effects in a large tract of forest versus a series of nearby forest fragments, to evaluate short-term response to hurricane disturbance in terms of mortality and sprouting, and to...