Long Term Monitoring

Long-term core measurements are designed to detect long term changes in major drivers (climate, sea level), material stocks and fluxes (water, nutrients, carbon, sediment), and key biotic (primary production, food web, biogeochemical cycling, respiration) and abiotic (sedimentation, porewater drainage) responses.

 

                                                                

Climate

Meteorological data are available from the Marshview Field Station (42.756971, -70.891366) in Newbury, MA. The station measures temperature, precipitation, humidity, wind speed and direction, atmospheric pressure, and solar radiation. The Marshview Field Station was installed on July 30, 2007. Between spring 2000 and July 30, 2007, the station was located on the grounds of Governor's Academy (formerly Governor Dummer Academy; 42.751484, -70.902407), Newbury, MA.

Wind speed and wind direction are also measured near the mouth of Plum Island Sound at the Ipswich Bay Yacht Club pier, Ipswich, MA.

Additional meteorological data for stations in Northeastern, MA are available through the NOAA National Climate Data Center (NCDC). NOAA/NCDC station names and search information used in PIE LTER research are listed in Other Data Links. Atmospheric deposition (wet and dry) is available through the National Atmospheric Deposition Program (NADP) at sites MA13 (Lexington, MA) and MA01 (Truro, MA).

Climate Data

Sea Level

An OTT (RLS) radar level system was installed on the IBYC pier in the fall of 2011. The sensor is mounted underneath the pier dock house with the sensor face plate looking down at the surface of the water. As the water level changes due to tidal water exchange the sensor measures the distance between the sensor face and the surface of the tidal water.'

YSI water quality sondes can also measure water level using a pressure strain gage sensor. The  pressure sensor measures water level changes above the sonde during tidal water exchange. YSI sondes have been deployed in the Parker River near the Middle Road Bridge, off the bulkhead at Fernald's Marine in the Parker River, and off the IBYC pier in Plum Island Sound.

Marsh water level is also measured using pressure sensors. Onset HOBO U20 series water level sensors have been installed in marsh pipes and adjacent river channels to allow measurements of marsh water level as tidal water exchange occurs. Groups of pipes with sensors leading away from the marsh/river channel edge allow various water levels in the marsh to be recorded and subsequent calculations of the amount of water exchanged between the river and the marsh porewater.

Eddy Flux Stations

Direct measurements of exchange of carbon dioxide between the salt marsh and the atmosphere allow us to estimate major parts of the carbon balance of this ecosystem. The measured net ecosystem exchange can be partitioned in gross primary production and ecosystem respiration. To measure this vertical exchange, two eddy covariance flux towers are located in the salt marshes of the Nelson Island Creek catchment. 'Nelson 1' tower was installed in 2011 and 'Nelson 2' tower was installed in 2012. While ‘Nelson 1’ is temporary and has to be removed during winter, ‘Nelson 2’ is running all year round. Together they provide a high resolution record of net carbon dioxide exchange, evapotranspiration and energy exchange. Measurements include air temperature, relative humidity, IRGA (CO2, H2O), 3D anemometer (u, v, w), net radiometer, PAR, soil temperature, water table level, and soil heat flux.

 

 

Primary Production

Above ground biomass and productivity of Spartina alterniflora and S. patens are monitored as control sites within a long-term plot-level marsh fertilization  experiment. Water column primary production (based on dawn-dusk O2 fluxes) and chlorophyll a concentrations are collected during semiannual transects of the Parker River Estuary. Benthic chlorophyll a data are available for selected subtidal sites in the Parker River. Long term data sets for vegetation transects are also available for
several sites.

Primary Production Data

Organic Matter

Organic matter gains and losses in the marshes are being monitored several ways. Most recently, instrumented towers are providing year-round monitoring of CO2 fluxes. Sediment Elevation Tables (SETs) installed throughout the marsh are monitored semi-annually, or annually in spring. Depths of feldspar marker horizons are measured at the same time. Long-term records of carbon and sediment deposition are also obtained as 210Pb profiles from marsh sediment cores.

Organic Matter Data

 

Inorganic Nutrients

Numerous long-term datasets describe nutrient concentrations and dynamics from the watershed, estuary, and marshes. They include data from repeated grab samples at dams discharging to the estuary, automated sampling of streams in the watersheds, transect sampling in the rivers and the estuary, porewater monitoring in the marshes, and nutrient fluxes from subtidal sediments. Additional long-term data on nutrients are associated with fertilization experiments as well as productivity and biomass measurements.

Inorganic Nutrient Data

Population Studies

Long term monitoring of PIE populations has included direct counts of organisms (for example fish, invertebrates, birds) as well as by using indicator measurements such as stable isotopes of C, N, and S, and in the case of phytoplankton, pigment analyses. We also make use of census data collected by others on species of commercial and/or conservation interest, such as Striped Bass and herring.

Population Dynamics Data