Drivers and Annual Totals of Methane Emissions From Dutch Peatlands.

Rewetting peatlands is required to limit carbon dioxide (CO) emissions, however, raising the groundwater level (GWL) will strongly increase the chance of methane (CH) emissions which has a higher radiative forcing than CO. Data sets of CH from different rewetting strategies and natural systems are scarce, and quantification and an understanding of the main drivers of CH emissions are needed to make effective peatland rewetting decisions. We present a large data set of CH fluxes (FCH) measured across 16 sites with eddy covariance on Dutch peatlands.

Emerging forest-peatland bistability and resilience of European peatland carbon stores.

Northern peatlands store large amounts of carbon. Observations indicate that forests and peatlands in northern biomes can be alternative stable states for a range of landscape settings. Climatic and hydrological changes may reduce the resilience of peatlands and forests, induce persistent shifts between these states, and release the carbon stored in peatlands.

Urban hydrogeology: Transport routes and mixing of water and solutes in a groundwater influenced urban lowland catchment.

Urban areas in coastal lowlands host a significant part of the world's population. In these areas, cities have often expanded to unfavorable locations that have to be drained or where excess rain water and groundwater need to be pumped away in order to maintain dry feet for its citizens. As a result, groundwater seepage influences surface water quality in many of such urban lowland catchments.

The changing contribution of top-down and bottom-up limitation of mesopredators during 220 years of land use and climate change.

Apex predators may buffer bottom-up driven ecosystem change, as top-down suppression may dampen herbivore and mesopredator responses to increased resource availability. However, theory suggests that for this buffering capacity to be realized, the equilibrium abundance of apex predators must increase. This raises the question: will apex predators maintain herbivore/mesopredator limitation, if bottom-up change relaxes resource constraints? Here, we explore changes in mesopredator (red fox Vulpes vulpes) abundance over 220 years in response to eradication and recovery of an apex predator (Eurasian lynx Lynx lynx), and changes in land use and climate which are linked to resource availability.

Improving load estimates for NO3 and P in surface waters by characterizing the concentration response to rainfall events.

For the evaluation of action programs to reduce surface water pollution, water authorities invest heavily in water quality monitoring. However, sampling frequencies are generally insufficient to capture the dynamical behavior of solute concentrations. For this study, we used on-site equipment that performed semicontinuous (15 min interval) NO(3) and P concentration measurements from June 2007 to July 2008.

Application and evaluation of a new passive sampler for measuring average solute concentrations in a catchment scale water quality monitoring study.

We present a field based testing, optimization, and evaluation study of the SorbiCell sampler (SC-sampler); a new passive sampling technique that measures average concentrations over longer periods of time (days to months) for various substances. We tested the SC-sampler within a catchment-scale monitoring study of NO(3) and P concentrations in surface water and tile drain effluent. Based on our field experiences, we optimized the flow velocity control and the sample volume capacity of the SC-samplers.