In urban catchments of arid central Arizona, we investigate how the export of mineral and organic nitrogen (N) in storm runoff is regulated by interactions between local landscape characteristics and broader scale storm features. First, we test whether N export is more a function of (1) processes that affect N concentration in runoff or (2) the propensity of the catchment to convey rainfall as ...

A multi-year, multi-technique study was conducted to measure evapotranspiration and its components within an uneven-aged mixed deciduous forest in the Southeastern United States. Four different measurement techniques were used, including soil water budget (1 year), sap flow (2 years), eddy covariance (5 years), and catchment water budget (31 years). Annual estimates of evapotranspiration were s...

1. We investigated the diversity and distribution of freshwater mussels at 40 sites in an agricultural catchment, the River Raisin in south-eastern Michigan, to relate mussel assemblages and individual taxa to reach and catchment-scale variables. Unionids were surveyed by timed searches in 100-m reaches, and in-stream and riparian habitat were quantified as well as flow, water chemistry and cha...

[1] The difficulties in predicting whole catchment water balance from observations at patch scales motivate a search for theories that can account for the complexity of interactions in catchments. In this paper we suggest that the spatial patterns of vegetation may offer a lens through which to investigate scale dependence of hydrology within catchments. Vegetation patterns are attractive becau...

The eco-hydrological model SWAT (Soil and Water Assessment Tool) is a useful tool to simulate the effects of catchment processes and water management practices on the water cycle. For each catchment some model parameters (e.g. ground water delay time, ground water level) remain constant and therefore are used as constant values; other parameters such as soil types or land use are spatially vari...

The nitrogen and carbon stable isotope ratios (dN and dC) of the pygmy mussel, Xenostrobus securis, were determined for three estuaries with varying levels of catchment disturbance in northern New South Wales, Australia. The lower Manning River catchment supported the highest human population densities and 3% residential development with some livestock agriculture (41%); the Wallamba River catc...

Stream benthic macroinvertebrates are useful indicators of the impacts of disturbances on catchment and stream conditions because they integrate many catchment-scale ecological processes. We tested the ability of macroinvertebrate assemblages over a 3-year period to indicate the impacts of a range of disturbances resulting from military training at the Fort Benning Military Installation, Georgi...

The KIDS model (Kielstau Discharge Simulation model) is a simple rainfall-runoff model developed originally for the Kielstau catchment. To extend its range of application we applied it to a completely different catchment, the XitaoXi catchment in China. Kielstau is a small (51 km2) lowland basin in Northern Germany, with large proportion of wetland area. And XitaoXi is a mesoscale (2271 km2) mo...

The effects of climate changes on nutrient discharges within the Baltic Sea catchment were modelled, indicating increases in concentrations of phosphorus, but decreases in nitrogen for the southern Baltic Sea catchment. The process-based hydrological and nutrient flux model, HYPE, was set up for the entire Baltic Sea catchment area. The model was then used to examine how water and nutrient flux...