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dissolved nutrient

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  • Nutrient survey (N and P concentrations)

  • The site of the Boknis Eck Time Series (BE) is located at the entrance of the Eckernförde Bay (54°31.2' N, 10°02.5' E) in the southwestern Baltic Sea. It has a water depth of 28 m with muddy sediments. Riverine inputs into the Eckernförde Bay are negligible and thus the overall hydrographic setting at BE is dominated by the regular inflow of North Sea water through the Kattegat and the Great Belt. Seasonal stratification occurs usually from mid-March until mid-September and causes pronounced hypoxia which sporadically become anoxic.

  • Cabras Lagoon is located on the west coast of Sardinia (Italy), in the Gulf of Oristano (39°56’37’’N, 08°28’43’’E), and occupies about 2280 ha, with a mean water depth and maximum of 1.6 and 3 m respectively. The watershed of the site extends over approximately 430 km2. The input of freshwater into the lagoon is scarce and irregular because of the semi-arid Mediterranean climate. Most of the freshwater comes from the small Mare ‘e Foghe River, located in the north. The predominance of agriculture in the region and the release of poorly depurated urban waste account for the high nutrient loads deposited in Cabras Lagoon. The resident population of about 38,000 inhabitants is grouped in 19 urban centres, the largest being Cabras, which is located on the southeast coastal side of the lagoon. During the twentieth century, the lagoon and its watershed underwent several modifications as a consequence of human activities that affected the hydrology and hydraulics of the region. In addition, in the late 1970s, water exchange with the sea was altered by the dredging of a large canal, the Scolmatore (spillway), which connected the lagoon with the adjacent Gulf of Oristano. The canal was constructed to avoid flooding of adjacent land during the heavy rainfall that occurs in winter. In addition, a cement dam was built into the Scolmatore to prevent further increases in the lagoon’s salinity and artificial barriers were constructed to control the fish catch, thereby impeding direct communication between the lagoon and the sea. Now the only link to the sea is via four very narrow creeks that flow into the large canal from the southern part of the lagoon over the barrier. The lagoon has a high economic rating due to ex¬tensive fishery activities, involving about 300 people and those involved in related enterprises. In the site, in addition to the guard houses and warehouses of fishermen, there is also a restaurant, where the products of fishery in the lagoon are offered. In 1998, fish productivity reached 40,000 kg km-2, corresponding to a catch of 850 tonnes but these values fell to around 20,000 kg km-2 and less than 80 tonnes after 1999. In fact, its high trophic status has often exposed the lagoon to important dystrophic crises, which have caused large reductions in its fishing productivity. Scientific monitoring has been carried out since the strong dystrophic crisis that affected Cabras Lagoon during the summer of 1999, killing the whole aquatic biota. A long-term series of data is available and derives from high-frequency measurements and samplings to assess environmental and biological parameters. In particular the data concern the main trophic descriptors (Secchi depth, temperature, pH, conductivity, dissolved oxygen and saturation, alkalinity, NH4-N, NO2-N, NO3-N, total nitrogen, soluble reactive phosphorus, total phosphorus, dissolved silica) and phytoplankton abundances, as chlorophyll a, cell densities and biomass, class and species composition. The activity was interrupted in 2009.

  • The mooring A is located in an open sea area close to Franklin Island, characterized by both clay bottom sediment and a flat morphology. The station can be considered as representative of the productivity and sedimentary conditions of the southern part of the Ross Sea, one of the areas considered to be affected by greater productivity rate.The study of mooring can be consider part of the activities conduct in the framework of the research project "ABIOCLEAR - Antarctic biogeochemical cycles - climatic and paleoclimatic reconstructions. (Resp. M. Ravaioli)". Such Project is the natural prosecution of previous research activity carried out from 1987. Objectives : Study of the particle fluxes towards the marine bottom sediment, in particular with the aim to obtain quali/quantitative estimate of the biogenica component coming from the primary production. Analysis of the vertical rain rate processes and, therefore, the marine cycle of the main biogenic particles such as Carbon and Silica. Try to obtain mass budgets of these parameters, estimating their cycle in the water column until the burial processes in sediments. From apparent accumulate rate calculated in the bottom sediment we will tried to discriminate the real vertical fluxes (Rain Rate) from the horizontal input from sediment remobilization processes. Acquisition and elaboration of long time series of data. Collection of bottom Sediment samples to estimate the variations of the productivity and the paleoproductivity in the area. Historical time series of Mooring A: Primary productivity data (every three years), fitoplancton, New and regenerated productivity, Seasonal, annual and interannual fluxes measure, monthly Particles samples, current velocity, water salinity, temperature and torbidity, Water-sediment interface measure. Biogeochemical parameters. Radiometrical Data, Mineralogical and grain size characterization. Nutrient, metals. Biostratigraphy interpretations. Lidar data are also available from 1997.

  • Research activities of the VCR/LTER focus on the mosaic of transitions and steady-state systems that comprise the barrier-island/lagoon/mainland landscape of the Eastern Shore of Virginia. Primary study sites are located on Hog Island, Parramore Island and mainland marshes near Nassawadox VA. The VCR/LTER uses field laboratory and housing facilities at the Anheuser-Busch Coastal Research Center in Oyster, VA.

  • The Moorea Coral Reef LTER site encompasses the coral reef complex that surrounds the island of Moorea, French Polynesia (17°30'S, 149°50'W). Moorea is a small, triangular volcanic island 20 km west of Tahiti in the Society Islands of French Polynesia.

  • The site consists of a marine databuoy equipped with a suite of sensors that monitor water quality parameters and acoustic receivers for the detection of Porpoises and tagged fish. The buoy is moored near an offshore windmill farm, approx. 30km off the coast on the Belgian Continental Shelf.

  • The Alimini Grande Lake has an elongate shape that develops almost parallel to the Adriatic coastline and overall its extension is 1,37 sqkm. It is linked to the Alimini Piccolo by a canal called Lu Strittu, 1300 metres long and from 10 up to 30 meters wide. The chemical-physical characteristics of the waters such as temperature, salinity and dissolved oxygen concentration have been studied for long time. The average salinity is 26.8 with a minimum of 2.7 in winter and a maximum of 41 in summer. Regarding the temperature, it shows the typical seasonal trend with the least minimum temperature recorded between December and January. The freshwater inflow from Traugnano, Strittu e Zuddeo canals descharges a load of nutrients collected from the catchment area surrounding Alimini Grande. Nevertheless on the basis of the measured nitrogen and phosphorus concentrations the lagoon can be considered mesotrophic, due to the water turnover and above all to the assimilation of nutrients by phytoplankton and bacteria. The lagoon is a nutrient trap, the rates of nitrogen and phosphorus salts in entrance are bigger than those exiting in the sea. For this reason, the lagoon has a relevant ecological function, confining and transferring the nutrients through the food webs within the area and acting as an ecological filter for the marine ecosystems. The Alimini Grande catchment basin has a surface of approximately 71 sqkm and almost 94% of the catchment basin (66 sqkm) is cultivated above all with olives and other sowing fields, requiring more than 300 tonnes per year of fertilizers (nitrogen and phosphorus total) and 3 tonnes of pesticide. The agricultural areas and the artificial surfaces as urban and industrial centers could have a potentially adverse impact on the lagoon because of the run-off waters inflowing through the hydrographic basin that provide high nutrient quantity, organic material and other pollutants. The lagoon is included in the Site of Community Importance (SCI) “Laghi Alimini” (CODE IT9150011) of the “Natura 2000 network”, according to the Habitat Directive 92/43/CEE. Some of the habitats of the lagoon are typical of the dune ecosystem and are of high naturalistic value, as the coastal dunes with junipers considered of priority interest, being present in less than 5% of the EU territory. The Alimini Lake biodiversity is so extraordinary that includes more than half of the vegetable species in Salento. The area is internationally known as located on the avifauna migratory route towards the northern Adriatic coast. In the last years the quantity and the diversity of wintering and migratory aquatic birds, such as the Mallard, Pochard, Coot and other Anatidae have been increasing.Currently the Alimini Lakes are subjects of study by the Department of Biological and Environmental Sciences and Technologies of the University of Salento aiming at the improvement of basic and applied ecological research activities on transitional waters.

  • In 1998 a permanent plot (50 x 50 m) was established on the slope of the Nosal Mountain at the height of 970 m asl in 120 year old spruce stand, where in the 120-year-old spruce stand bulk deposition, throughfall and soil solution are collected. The investigations of health status of trees and floral characteristic have been carried out since 2001. The analyses are carried out in a certified laboratory of the Institute for Ecology of Industrial Areas, Katowice (Certificate No AB 325). The basic meteo data are taken from the monitoring station located at Kuźnice (about 1 kn from the plot).

  • UK ECN site. The River Lathkill is located in the Peak District National Park and is designated a Site of Special Scientific Interest (SSSI). The site is part of a the Peak District Dales SAC under the Habitats Directive. It is the only river in Britain which rises in, as well as flows through limestone for its entire length. The upper parts are a winterbourne, and in summer the stream issues from bubble springs lower down the valley. Downstream there are alternately moderately flowing gravelly sections and silted pools, some formed by natural tufa dams, others artificially. In the pools there are abundant submerged plants including species of Veronica, Ranunculus, Potamogeton and Callitriche, while faster sections are carpeted with bryophytes, some of which are nationally rare (eg. Cratoneuron commutatum). There are no direct discharges to the river. There are two licensed abstractions for fish rearing purposes and there are concerns over low flows which may affect water quality and the biota.