New infrastructure for research on land-ocean interactions
Coastal ecosystems in southern and western parts of Norway have experienced major changes over the last 2-3 decades with dramatic loss of kelp forest, rapid expansion of fouling algae, and large fluctuations and declining trends in near-shore fish populations. Several factors may have led to this ecosystem change, individually or in combination: excess inputs of nutrients, organic matter and contaminants, increased seawater temperature, increased freshwater inputs, oxygen depletion, reduced underwater light conditions and over-fishing. The freshwater – marine continuum entails several environmental gradients of crucial importance for biogeochemical processes and ecosystem functions. Major knowledge gaps exist in the complex interplay between long-term environmental change, element cycling, uptake, food web transfer and related ecosystem effects. This is a particular concern as climate change alters the input of freshwater and influences several of the processes along the continuum in such a way that further ecosystem disturbances can be expected and compliance with the goals set by the Water framework Directive will be increasingly difficult to reach in the future.
To facilitate research on land-ocean interactions the Norwegian Institute for Water Research (NIVA), with financial support from the Norwegian Ministry of Climate and Environment, has established a new infrastructure in a river-fjord system (Storelva river – Sandnesfjord) close to Tvedestrand in Aust-Agder County; Latitude: 58.6748 N, longitude: 9.01677 E.
About the infrastructure
The research infrastructure currently consists of two monitoring stations with continuous measurements of several physical and chemical variables; one is located at the outlet of river Storelva; the other in the middle fjord basin (Nævestedfjord). In adition, a weather station is established close to the fjord station. Online data from all three monitoring stations are transferred to NIVA’s Aquamonitor server in Oslo (see panel on the left).
Storelva outlet (Lake Lundevann): Continuous monitoring of water temperature, pH, conductivity, turbidity, and water colour (CDOM). See location 1 on map.
Nævestad fjord: Continuous monitoring of water temperature, salinity, turbidity, and water colour (CDOM) at six depths between 1 and 9 meters. See location 4 on map.
Weather station at Nævestadfjorden: Continuous monitoring of air pressure, air temperature, humidity, wind speed and wind direction. See location 4 on map.