scholarly journals Seasonal steady-state budgets of nutrients and stoichiometric calculations in an Eastern Mediterranean lagoon (Papas Lagoon-Greece)

2011 ◽  
Vol 12 (1) ◽  
pp. 21 ◽  
Author(s):  
E. KRASAKOPOULOU ◽  
K. PAGOU
Keyword(s):  
Eastern Mediterranean ◽  
Inorganic Nitrogen ◽  
Meteorological Data ◽  
Single Layer ◽  
Inorganic Phosphorus ◽  
Temporal Variations ◽  
Gross Photosynthesis ◽  
State Budgets ◽  
Physicochemical Data ◽  
Shallow Water Body

The Papas Lagoon is an enclosed, small shallow water body in western Greece. The lagoon is naturally affected by eutrophication phenomena, but occasionally during the summer season, dystrophic crises occur, related to the decomposition of large beds of macroalgae. Physicochemical data collected monthly, from June 1998 to September 1999, were compiled and coupled with historical meteorological data, in order to construct seasonal water, salt and nutrients budgets using a single box single layer LOICZ model. Nutrients and other hydrochemical parameters exhibit great spatial and temporal variations. The non-conservative dissolved inorganic phosphorus flux (ΔDIP) is always positive, thus indicating that the system acts as a net source of DIP for the adjacent coastal waters. Higher values were estimated  uring summer and autumn, probably due to organic matter mineralisation and release of DIP from surficial sediments in the reduced environment. In contrast to the ΔDIP, the non-conservative balance of dissolved inorganic nitrogen (ΔDIN) is negative for most of the year, except for the summer, indicating the dominance of DIN removal processes in the Papas Lagoon. The Ulva growth and decomposition processes seem likely to be of essential importance for the evaluation of the non-conservative DIN fluxes. During the investigated period the amount of organic carbon respired and mineralized is greater than that produced by gross photosynthesis and the Papas Lagoon is a net heterotrophic system. Losses of DIN via denitrification appear to dominate over its inputs through nitrogen fixation throughout the year.

scholarly journals Temporal variation of nitrate and phosphate transport in headwater catchments: the hydrological controls and landuse alteration

2012 ◽  
Vol 9 (9) ◽  
pp. 13211-13241 ◽  
Author(s):  
T.-Y. Lee ◽  
J.-C. Huang ◽  
S.-J. Kao ◽  
C.-P. Tung
Keyword(s):  
Nitrogen Saturation ◽  
Inorganic Nitrogen ◽  
Phosphate Transport ◽  
Inorganic Phosphorus ◽  
Fertilizer Application ◽  
Temporal Variations ◽  
Phosphorus Transport ◽  
Headwater Catchments ◽  
High Level ◽  
The Impact

Abstract. Oceania Rivers are hotspots of high DIN (dissolved inorganic nitrogen) and DIP (dissolved inorganic phosphorus) transport. However, the effects of hydrologic controls and land use alternation on the temporal variations of DIN and DIP are rarely documented. In this study, we monitored the nitrate and phosphate concentrations from three headwater catchments with different cultivation gradients at a 3-day interval. This sampling scheme was supplemented with a 3-h interval monitoring during typhoon periods. The results showed that the DIN and DIP yields in the pristine, moderately cultivated, and intensively cultivated watersheds were 7.52/0.31, 31.17/0.30, and 40.96/0.52 kg ha−1 yr−1, respectively. The high DIN yields are comparable to the intensively and extensively disturbed large rivers around the world. These N yields may be due to a high level of nitrogen deposition, rainfall-runoff, and fertilizer application. The importance of event sampling was indicated by the contribution of the three typhoons to the annual DIN and DIP fluxes, which were 30% and 60%, respectively. Both DIN and DIP fluxes significantly increased as the cultivation gradient increased. The DIN and DIP ratio varied from 54 to 230 depending on the decrease of the cultivation gradient. This value is higher than the global mean of ~18. Thus, we speculate that nitrogen saturation occurs in the headwater catchments of Oceania Rivers. The results obtained provide fundamental clues of DIN and DIP yield of Oceania Rivers, which are helpful in understanding the impact of human disturbance on headwater watersheds.

scholarly journals Understanding the seasonality of performance resilience to climate volatility in Mediterranean dairy sheep

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Valentina Tsartsianidou ◽  
Vanessa Varvara Kapsona ◽  
Enrique Sánchez-Molano ◽  
Zoitsa Basdagianni ◽  
Maria Jesús Carabaño ◽  
...  
Keyword(s):  
Genetic Control ◽  
Milk Production ◽  
Eastern Mediterranean ◽  
Meteorological Data ◽  
Genetic Correlations ◽  
Farm Animals ◽  
Seasonal Effects ◽  
Cold Weather ◽  
Adverse Weather ◽  
The Impact

AbstractAs future climate challenges become increasingly evident, enhancing performance resilience of farm animals may contribute to mitigation against adverse weather and seasonal variation, and underpin livestock farming sustainability. In the present study, we develop novel seasonal resilience phenotypes reflecting milk production changes to fluctuating weather. We evaluate the impact of calendar season (autumn, winter and spring) on animal performance resilience by analysing 420,534 milk records of 36,908 milking ewes of the Chios breed together with relevant meteorological data from eastern Mediterranean. We reveal substantial seasonal effects on resilience and significant heritable trait variation (h2 = 0.03–0.17). Resilience to cold weather (10 °C) of animals that start producing milk in spring was under different genetic control compared to autumn and winter as exemplified by negative genetic correlations (− 0.09 to − 0.27). Animal resilience to hot weather (25 °C) was partially under the same genetic control with genetic correlations between seasons ranging from 0.43 to 0.86. We report both favourable and antagonistic associations between animal resilience and lifetime milk production, depending on calendar season and the desirable direction of genetic selection. Concluding, we emphasise on seasonal adaptation of animals to climate and the need to incorporate the novel seasonal traits in future selective breeding programmes.

scholarly journals Using the significant dust deposition event on the glaciers of Mt. Elbrus, Caucasus Mountains, Russia on 5 May 2009 to develop a method for dating and "provenancing" of desert dust events recorded in snow pack

2013 ◽  
Vol 13 (4) ◽  
pp. 1797-1808 ◽  
Author(s):  
M. Shahgedanova ◽  
S. Kutuzov ◽  
K. H. White ◽  
G. Nosenko
Keyword(s):  
Eastern Mediterranean ◽  
Meteorological Data ◽  
Source Region ◽  
Secondary Source ◽  
Snow Pack ◽  
Dust Deposition ◽  
Hysplit Model ◽  
Pressure System ◽  
Desert Dust ◽  
Caucasus Mountains

Abstract. A significant desert dust deposition event occurred on Mt. Elbrus, Caucasus Mountains, Russia on 5 May 2009, where the deposited dust later appeared as a brown layer in the snow pack. An examination of dust transportation history and analysis of chemical and physical properties of the deposited dust were used to develop a new approach for high-resolution "provenancing" of dust deposition events recorded in snow pack using multiple independent techniques. A combination of SEVIRI red-green-blue composite imagery, MODIS atmospheric optical depth fields derived using the Deep Blue algorithm, air mass trajectories derived with HYSPLIT model and analysis of meteorological data enabled identification of dust source regions with high temporal (hours) and spatial (ca. 100 km) resolution. Dust, deposited on 5 May 2009, originated in the foothills of the Djebel Akhdar in eastern Libya where dust sources were activated by the intrusion of cold air from the Mediterranean Sea and Saharan low pressure system and transported to the Caucasus along the eastern Mediterranean coast, Syria and Turkey. Particles with an average diameter below 8 μm accounted for 90% of the measured particles in the sample with a mean of 3.58 μm, median 2.48 μm. The chemical signature of this long-travelled dust was significantly different from the locally-produced dust and close to that of soils collected in a palaeolake in the source region, in concentrations of hematite. Potential addition of dust from a secondary source in northern Mesopotamia introduced uncertainty in the "provenancing" of dust from this event. Nevertheless, the approach adopted here enables other dust horizons in the snowpack to be linked to specific dust transport events recorded in remote sensing and meteorological data archives.

scholarly journals TESTING OF CHLORELLA/SCENEDESMUS MICROALGAE CONSORTIA FOR REMEDIATION OF WASTEWATER, CO₂ MITIGATION AND ALGAE BIOMASS FEASIBILITY FOR LIPID PRODUCTION

2014 ◽  
Vol 22 (2) ◽  
pp. 105-114 ◽  
Author(s):  
Judita Koreivienė ◽  
Robertas Valčiukas ◽  
Jūratė Karosienė ◽  
Pranas Baltrėnas
Keyword(s):  
Municipal Wastewater ◽  
Global Climate ◽  
Inorganic Nitrogen ◽  
Lipid Production ◽  
Single Species ◽  
Inorganic Phosphorus ◽  
Climatic Conditions ◽  
Biofuel Production ◽  
Treated Wastewater ◽  
Algae Biomass

Industry, transport and unsustainable agriculture result in the increased quantity of wastewater, release of nutrients and emission of carbon dioxide that promotes eutrophication of water bodies and global climate change. the application of microalgae for phycoremediation, their biomass use for human needs may increase sustainability and have a positive effect on the regional development. The experiments were carried out in order to establish the feasibility of treating the local municipal wastewater with microalgae consortia and their biomass potential for biofuel production. The results revealed that Chlorella/Scenedesmus consortium eliminated up to 99.7–99.9% of inorganic phosphorus and up to 88.6–96.4% of inorganic nitrogen from the wastewater within three weeks. The ammonium removal was more efficient than that of nitrate. Chlorella algae grew better in diluted, while Scenedesmus – in the concentrated wastewater. The consortium treated wastewater more efficiently than a single species. The maximum biomass (3.04 g/L) of algal consortium was estimated in concentrated wastewater. Algae accumulated 0.65–1.37 g of CO2/L per day in their biomass. Tus, Chlorella/Scenedesmus consortium is a promising tool for nutrients elimination from the local wastewater under the climatic conditions specific to Lithuania. However, none of the two species were able to accumulate lipids under the nitrogen starvation conditions.

scholarly journals Surface melt magnitude retrieval over Ross Ice Shelf, Antarctica using coupled MODIS near-IR and thermal satellite measurements

2009 ◽  
Vol 3 (3) ◽  
pp. 1069-1107 ◽  
Author(s):  
D. J. Lampkin ◽  
C. C. Karmosky
Keyword(s):  
Meteorological Data ◽  
Temporal Variations ◽  
Katabatic Wind ◽  
Ice Shelf ◽  
Water Fraction ◽  
Ross Ice Shelf ◽  
Near Ir ◽  
Coarse Spatial Resolution ◽  
Surface Melt ◽  
The Antarctic

Abstract. Surface melt has been increasing over recent years, especially over the Antarctic Peninsula, contributing to disintegration of shelves such as Larsen. Unfortunately, we are not realistically able to quantify surface snowmelt from ground-based methods because there is sparse coverage of automatic weather stations. Satellite based assessments of melt from passive microwave systems are limited in that they only provide an indication of melt occurrence and have coarse spatial resolution. An algorithm was developed to retrieve surface melt magnitude using coupled near-IR/thermal surface measurements from MODIS were calibrated by estimates of liquid water fraction (LWF) in the upper 1 cm of the firn derived from a one-dimensional physical snowmelt model (SNTHERM89). For the modeling phase of this study, SNTHERM89 was forced by hourly meteorological data from automatic weather station data at reference sites spanning a range of melt conditions across the Ross Ice Shelf during a relatively intense melt season (2002). Effective melt magnitude or LWF<eff> were derived for satellite composite periods covering the Antarctic summer months at a 4 km resolution over the entire Ross Ice Shelf, ranging from 0–0.5% LWF<eff> in early December to areas along the coast with as much as 1% LWF<eff> during the time of peak surface melt. Spatial and temporal variations in the magnitude of surface melt are related to both katabatic wind strength and advection during onshore flow.

scholarly journals Climatic and atmospheric circulation pattern variability from ice-core isotope/geochemistry records (Altai, Tien Shan and Tibet)

2006 ◽  
Vol 43 ◽  
pp. 49-60 ◽  
Author(s):  
Vladimir B. Aizen ◽  
Elena M. Aizen ◽  
Daniel R. Joswiak ◽  
Koji Fujita ◽  
Nozomu Takeuchi ◽  
...  
Keyword(s):  
Air Temperature ◽  
Isotope Geochemistry ◽  
Eastern Mediterranean ◽  
Meteorological Data ◽  
Ice Core ◽  
Ice Cores ◽  
Snow Accumulation ◽  
Tien Shan ◽  
Synoptic Climatology ◽  
The Tibetan Plateau

AbstractSeveral firn/ice cores were recovered from the Siberian Altai (Belukha plateau), central Tien Shan (Inilchek glacier) and the Tibetan Plateau (Zuoqiupu glacier, Bomi) from 1998 to 2003. The comparison analyses of stable-isotope/geochemistry records obtained from these firn/ice cores identified the physical links controlling the climate-related signals at the seasonal-scale variability. The core data related to physical stratigraphy, meteorology and synoptic atmospheric dynamics were the basis for calibration, validation and clustering of the relationships between the firn-/ice-core isotope/ geochemistry and snow accumulation, air temperature and precipitation origin. The mean annual accumulation (in water equivalent) was 106 gcm−2 a−1 at Inilchek glacier, 69 gcm−2 a−1 at Belukha and 196 g cm−2 a−1 at Zuoqiupu. The slopes in regression lines between the δ18O ice-core records and air temperature were found to be positive for the Tien Shan and Altai glaciers and negative for southeastern Tibet, where heavy amounts of isotopically depleted precipitation occur during summer monsoons. The technique of coupling synoptic climatology and meteorological data with δ18O and d-excess in firn-core records was developed to determine climate-related signals and to identify the origin of moisture. In Altai, two-thirds of accumulation from 1984 to 2001 was formed from oceanic precipitation, and the rest of the precipitation was recycled over Aral–Caspian sources. In the Tien Shan, 87% of snow accumulation forms by precipitation originating from the Aral–Caspian closed basin, the eastern Mediterranean and Black Seas, and 13% from the North Atlantic.

Optical Properties, Suspended Sediments, and Chemistry Associated with the Turbidity Maxima of the Delaware Estuary

1983 ◽  
Vol 40 (S1) ◽  
pp. s172-s179 ◽  
Author(s):  
Robert B. Biggs ◽  
Jonathan H. Sharp ◽  
Thomas M. Church ◽  
John M. Tramontano
Keyword(s):  
Optical Properties ◽  
Trace Metals ◽  
Attenuation Coefficient ◽  
Inorganic Nitrogen ◽  
Suspended Sediments ◽  
Inorganic Phosphorus ◽  
Turbidity Maximum ◽  
Salinity Range ◽  
Delaware Estuary ◽  
High Concentrations

Two turbidity maxima were found in the Delaware Estuary and were distinct both in terms of optical properties of the water and in quantity of suspended material. The upstream maximum occurred at about 1‰ salinity. Both the diffuse attenuation coefficient (KD) and the beam attenuation coefficient (α) responded to the double turbidity maxima. The upstream maximum contains a larger number of individual mineral grains with a mean diameter of about 3 μm; the downstream maximum, which occurred at salinities of 7.5–10‰, was dominated by composite particles with a mean size of 12 μm; at salinities > 10‰, the suspended sediment population was dominated by large (10–20 μm) individual particles with few composite particles.Nutrients, productivity, particulate organic matter, and dissolved and particulate metals all showed relationships to the turbidity maxima when viewed on salinity and on geographic axes. An excess of dissolved inorganic nitrogen in relation to dissolved inorganic phosphorus was mirrored by exceptionally low particulate C/P ratios in the region of the turbidity maxima. Primary productivity appeared to be greatly reduced in the region of the downstream turbidity maximum.The trace metals Fe, Mn, Cd, Cu, Co, and Ni showed a general association with particulate phases at lowest salinities, at the upstream turbidity maximum. The more particle reactive metals (Fe, Mn, and Co) reflected this as enrichment relative to particulate aluminum. At the downstream turbidity maximum, in the mid-salinity range, the trace metals showed a minimum relative to Al, probably due to dilution by resuspended bottom sediments. In the lower estuary, the trace metals exhibited the highest enrichment (relative to aluminum) and an association with high concentrations of particulate carbon.Key words: Delaware Estuary, turbidity maxima, optical properties, suspended sediments, chemistry

scholarly journals Deterioration in the water quality of an urbanised estuary with recommendations for improvement

Water SA ◽  
2019 ◽  
Vol 45 (1 January) ◽  
Author(s):  
Adams JB ◽  
L Pretorius ◽  
GC Snow
Keyword(s):  
Water Quality ◽  
Inorganic Nitrogen ◽  
Vertical Mixing ◽  
Primary Source ◽  
Inorganic Phosphorus ◽  
Quality Data ◽  
Spatial And Temporal Variability ◽  
Phytoplankton Blooms ◽  
Water Quality Data

Water quality characteristics of the heavily urbanised and industrialised Swartkops River and Estuary in the Eastern Cape have been the focus of several studies since the 1970s. Overloaded and poorly maintained wastewater treatment works (WWTWs), polluted stormwater runoff and solid waste have all contributed to the deterioration in the water quality of the river and estuary. The objective of this study was to determine the current water quality status of the Swartkops Estuary, by investigating spatial and temporal variability in physico-chemical parameters and phytoplankton biomass and where possiblerelate this to historical water quality data. The present study found evidence suggesting that water is not flushed as efficiently from the upper reaches of the estuary as was previously recorded. Reduced vertical mixing results in strong stratification and persistent eutrophic conditions with phytoplankton blooms (> 20 μg chl a·L−1), extending from the middle reaches to the tidal head of the estuary. The Motherwell Canal was and still is a major source of nitrogen (particularly ammonium) to the estuary, but the Swartkops River is the primary source of phosphorus with excessive inputs from the cumulative effectof three WWTWs upstream. An analysis of historical water quality data in the Swartkops Estuary (1995 to 2013) shows that all recorded dissolved inorganic phosphorus measurements were classified as hypertrophic (> 0.1 mg P·L−1), whereas 41% of dissolved inorganic nitrogen measurements were either mesotrophic or eutrophic. If nutrient removal methods at the three WWTWs were improved and urban runoff into the Motherwell Canal better managed, it is likely that persistent phytoplankton blooms and health risks associated with eutrophication could be reduced.

Comparison of Modeled-to-Monitored PM2.5 Exposure Concentrations Resulting from Transportation Emissions in a Near-Road Community

2020 ◽  
Vol 2674 (12) ◽  
pp. 130-143
Author(s):  
Mayra Chavez ◽  
Wen-Whai Li
Keyword(s):  
Air Quality ◽  
Meteorological Data ◽  
Temporal Variations ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Spatial And Temporal Variations ◽  
Quality Data ◽  
Background Concentrations ◽  
Regional Background ◽  
Transportation Emissions

Residents living in near-road communities are exposed to traffic-related air pollutants, which can adversely affect their health. Near-road communities are expected to observe significant spatial and temporal variations in pollutant concentrations. Determining these variations in the surrounding areas can help raise awareness among government agencies of these underserved communities living near highways. This study conducted traffic and air quality measurements along with emission and dispersion modeling of the exposure to transportation emissions of a near-road urban community adjacent to the US 54 highway (US 54), with annual average daily traffic (AADT) of 107,237. The objectives of this study were (i) to develop spatial and temporal patterns of pollutant concentration variation and (ii) to apportion the differences in exposure concentrations to background concentrations and those that are contributed from major highways. It was observed that: (a) particulate matter (PM2.5) in near-road communities is dominated by the regional background concentrations which account for more than 85% of the pollution; and (b) only near-road receptors are affected by the traffic-related air pollutant emissions from major highways while spatial and temporal variations of PM2.5 concentrations in near-road communities are less influenced by local traffic, subsiding rapidly to negligible concentrations at 300 m from the road. Modeled PM2.5 concentrations were compared with monitored data. For better air quality impact assessments, higher quality data such as time-specific traffic volume and fleet information as well as site-specific meteorological data could help yield more accurate concentration predictions. Modeled-to-monitored comparison shows that air quality in near-road communities is dominated by regional background concentrations.

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