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1.
Impact of intensive agricultural practices on drinking water quality in the EVROS Region (NE GREECE) by GIS analysis 总被引:1,自引:0,他引:1
Chemical fertilizers are used extensively in modern agriculture, in order to improve yield and productivity of agricultural products. However, nutrient leaching from agricultural soil into groundwater resources poses a major environmental and public health concern. The Evros region is one of the largest agricultural areas in Northern Greece, extending over 1.5 million acres of cultivated land. Many of its drinking water resources are of groundwater origin and lie within agricultural areas. In order to assess the impact of agricultural fertilizers on drinking water quality in this region, tap-water samples from 64 different locations were collected and analyzed for the presence of nitrates [Formula: see text], nitrites [Formula: see text], ammonium [Formula: see text], sulfate [Formula: see text] and phosphate [Formula: see text]. These chemicals were selected based on the information that ammonium nitrate, ammonium sulfate and inorganic phosphate were the primary fertilizers used in local crop production. [Formula: see text], [Formula: see text] and [Formula: see text] levels exceeding accepted values were recorded in 6.25, 4.70 and 9.38% of all sampling points, respectively. [Formula: see text] and [Formula: see text] concentrations, on the other hand, were inside the permitted range. The data generated were introduced into a geographic information system (GIS) program for computer analysis and projection maps representing afflicted areas were created. Our results indicate a profound geographic correlation in the surface distribution of primary contaminants in areas of intensified agricultural production. Thus, drinking water pollution in these areas can be attributed to excessive fertilizer use from agricultural sources. 相似文献
2.
Hock Hwee Heng Nikolas P. Nikolaidis 《Journal of the American Water Resources Association》1998,34(2):359-374
ABSTRACT: The Watershed Nutrient Transport and Transformation (NTT-Watershed) model is a physically based, energy-driven, multiple land use, distributed model that is capable of simulating water and nutrient transport in a watershed. The topographic features and subsurface properties of the watershed are refined into uniform, homogeneous square grids. The vertical discretization includes vegetation, overland flow, soil water redistribution and groundwater zones. The chemical submodel simulates the nitrogen dynamics in terrestrial and aquatic systems. Three chemical state variables are considered (NO3--, NH4+, and Org-N). The NTT-Watershed model was used to simulate the fate and transport of nitrogen in the Muddy Brook watershed in Connecticut. The model was shown to be capable of capturing the hydrologic and portions of the nitrogen dynamics in the watershed. Watershed planners could use this model in developing strategies of best management practices that could result in maximizing the reductions of nitrogen export from a watershed. 相似文献
3.
Marine environmental pollution has been considered by all human social classes to be a problem of major importance. Comparing measurements carried out in marine macrophyceae derived from the Gulf of Kavala and Pylos we have concluded the following, the element Pb having been taken into account. Seasonal variations are detected in the Pb content of the macrophyceae species examined. Pb, which is regarded as one of the most toxic metals, is not encountered in great quantities in these biotopes. The Pb content in the algae of the harbour of Kavala is higher than in the other two stations (Palio, Kavala and Pylos). 相似文献
4.
Bryan Boulanger Nikolaos P. Nikolaidis 《Journal of the American Water Resources Association》2003,39(2):337-345
ABSTRACT: A modeling framework was developed for managing copper runoff in urban watersheds that incorporates water quality characterization, watershed land use areas, hydrologic data, a statistical simulator, a biotic ligand binding model to characterize acute toxicity, and a statistical method for setting a watershed specific copper loading. The modeling framework is driven by export coefficients derived from water quality parameters and hydrologic inputs measured in an urban watershed's storm water system. This framework was applied to a watershed containing a copper roof built in 1992. A series of simulations was run to predict the change in receiving stream water chemistry caused by roof aging and to determine the maximum copper loading (at the 99 percent confidence level) a watershed could accept without causing acute toxicity in the receiving stream. Forecasting the amount of copper flux responsible for exceeding the assimilation capacity of a watershed can be directly related to maximum copper loadings responsible for causing toxicity in the receiving streams. The framework developed in this study can be used to evaluate copper utilization in urban watersheds. 相似文献
5.
Ourania Tzoraki Nikolaos P. Nikolaidis David Cooper Elissavet Kassotaki 《Environmental monitoring and assessment》2014,186(4):2243-2257
We estimate the nutrient budget in a temporary Mediterranean river basin. We use field monitoring and modelling tools to estimate nutrient sources and transfer in both high and low flow conditions. Inverse modelling by the help of PHREEQC model validated the hypothesis of a losing stream during the dry period. Soil and Water Assessment Tool model captured the water quality of the basin. The ‘total daily maximum load’ approach is used to estimate the nutrient flux status by flow class, indicating that almost 60 % of the river network fails to meet nitrogen criteria and 50 % phosphate criteria. We recommend that existing well-documented remediation measures such as reforestation of the riparian area or composting of food process biosolids should be implemented to achieve load reduction in close conjunction with social needs. 相似文献
6.
Stamati F Nikolaidis N Dimitriou E Koussouris T 《Journal of environmental quality》2008,37(1):164-173
The hydrologic and geochemical conditions that prevail in Mediterranean temporary ponds (MTPs), create a unique environment for many rare and endangered species. Mediterranean temporary ponds are habitats of high ecological value, which are vulnerable to imminent climatic changes, as well as to human activities. This article examines the hydrology and the nitrogen and phosphorous geochemical cycles of four MTPs in Crete. Field and laboratory studies provided the necessary information for the development of a conceptual understanding of the hydrologic and biogeochemical processes that affect the fate of nitrogen and phosphorous in these MTPs. Their hydrology was driven by deposition, infiltration, and evaporation. The hydroperiod of the ponds varied between 40 and 160 d. Mineralization and nutrient release capacity experiments illustrated the significant role that MTP sediments played in enhancing the geochemistry of the aqueous phase. Such ecosystem functions (i.e., mineralization, nutrient release) exhibited high variability among MTPs necessitating site-specific studies with immediate implications to management. It is very important to understand the local hydrogeochemical and climatic conditions to ensure appropriate environmental measures for their management and conservation. 相似文献
7.
An integrated approach to watershed management within the DPSIR framework: Axios River catchment and Thermaikos Gulf 总被引:8,自引:0,他引:8
A. P. Karageorgis M. S. Skourtos V. Kapsimalis A. D. Kontogianni N. Th. Skoulikidis K. Pagou N. P. Nikolaidis P. Drakopoulou B. Zanou H. Karamanos Z. Levkov Ch. Anagnostou 《Regional Environmental Change》2005,5(2-3):138-160
The coastal zone of the inner Thermaikos Gulf has been influenced by eutrophication during the past decades. The conditions of the catchment area-coastal zone continuum are assessed under the holistic Driver-Pressure-State-Impact-Response (DPSIR) framework. Major socioeconomic drivers, such as industrial and agricultural development as well as urbanization, exert substantial environmental pressures on the Axios River and the Thermaikos Gulf. The Thermaikos Gulf is a highly complex system, being affected by nutrient inputs from four rivers and the City of Thessaloniki. Moreover, the Axios River which is the most significant contributor of freshwater and nutrients to the gulf, is a transboundary river shared between Greece and the Former Yugoslav Republic of Macedonia (FYROM). The two countries have not yet established a mutual management plan to control freshwater and nutrient discharges. Long-term analysis has shown that presently, more than 11,800 t of nitrogen and 3,400 t of phosphorous are released annually into the marine system. In the Antropocene era, and particularly during the past 20 years, freshwater discharges have decreased and riverine nutrients have increased, whereas inputs from domestic and industrial effluents have a decreasing trend. However, nutrient over-enrichment impacts, i.e. eutrophication, harmful algal blooms and hypoxia still have to be addressed in order to identify whether the coastal system is recovering, or whether further actions should be undertaken to control nutrient inputs from the Axios River and/or other sources. Response actions, such as the improvement of Thessalonikis wastewater treatment plant, have proved to play a positive role in the reduction of domestic wastewater input in the gulf, whereas similar facilities are completely lacking in FYROM. On the other hand, several parts of the Axios River delta are designated as protected areas, in an effort to protect environmentally rich habitats. These efforts are often disputed by local stakeholders, which have conflicting interests in the use of the hinterland and the coastal environment. The need of an integrated catchment-coastal zone management plan appears as a fundamental priority in order to protect, improve and maintain the environment, taking into account the need for economic development of the area. The DPSIR conceptual framework appears to be a valuable tool, as it enables parallel assessment of socioeconomic and environmental issues. In combination with the application of numerical models, the DPSIR analysis may provide suggestions for sustainable and environmentally-friendly measures to policy makers.SI: Pirrone 相似文献
8.
Bryan Boulanger Nikolaos P. Nikolaidis 《Journal of the American Water Resources Association》2003,39(2):325-336
ABSTRACT: Abundant use of copper based products has resulted in increased violation of copper water quality criteria in runoff from urban storm water systems. The objectives of this work were to understand the mobility and toxicity of copper in an urban watershed and to apportion the amount of copper entering the freshwater receiving stream from different urban land covers using a mass balance approach. Sixteen rainfall events collected from the University of Connecticut study watershed between August 1998 and September 2000 were analyzed to assess copper flux in an urban storm water system. Mean flow weighted dissolved copper concentrations observed in the study for copper based architectural material runoff, pervious area runoff, impervious area runoff, and in the receiving stream were 1210 ± 840, 9 ± 3, 8 ± 2, and 14 ± 7 μg/L, respectively. Mean dissolved copper concentrations in the receiving stream exceeded Connecticut's water quality criteria. Despite exceeding the dissolved concentration based criteria, cupric ion concentrations at the system outlet remained below 0.05 μg/L for all storms analyzed, and no acute toxicity (using Daphnia pulex as the test organism) was measured in samples collected from the stream. 相似文献
9.
Manoj Menon Svetla Rousseva Nikolaos P. Nikolaidis Pauline van Gaans Panos Panagos Danielle Maia de Souza Kristin Vala Ragnarsdottir Georg J. Lair Liping Weng Jaap Bloem Pavel Kram Martin Novak Brynhildur Davidsdottir Gudrun Gisladottir David A. Robinson Brian Reynolds Tim White Lars Lundin Bin Zhang Christopher Duffy Stefano M. Bernasconi Peter de Ruiter Winfried E. H. Blum Steven A. Banwart 《Environmental science and pollution research international》2014,21(4):3191-3195
Soil is a complex natural resource that is considered non-renewable in policy frameworks, and it plays a key role in maintaining a variety of ecosystem services (ES) and life-sustaining material cycles within the Earth's Critical Zone (CZ). However, currently, the ability of soil to deliver these services is being drastically reduced in many locations, and global loss of soil ecosystem services is estimated to increase each year as a result of many different threats, such as erosion and soil carbon loss. The European Union Thematic Strategy for Soil Protection alerts policy makers of the need to protect soil and proposes measures to mitigate soil degradation. In this context, the European Commission-funded research project on Soil Transformations in European Catchments (SoilTrEC) aims to quantify the processes that deliver soil ecosystem services in the Earth's Critical Zone and to quantify the impacts of environmental change on key soil functions. This is achieved by integrating the research results into decision-support tools and applying methods of economic valuation to soil ecosystem services. In this paper, we provide an overview of the SoilTrEC project, its organization, partnerships and implementation. 相似文献
10.
In this work, the potential for natural attenuation (NA) of Cr(VI) is evaluated for sub-wetland ground water at a chromium-contaminated site in Connecticut, incorporating the experimental findings of previous work at the site. Experimental data is assessed through long-term attenuation capacity calculations and modeling, which incorporates statistical uncertainty of parametric values. The NA evaluation yielded the following results: (1) Significant increases in Cr(VI) concentration and extremely long chromium source dissolution timeframes are required to exceed the attenuation capacity of the sub-wetland region soils studied in this work; and (2) Based on the 1-D transport modeling and incorporating input parameter uncertainty, there is an approximately 92% and 98% probability that the applicable regulatory criteria will not be exceeded at Point C, near a river which serves as the receptor, for the cases of (1) sorption of Cr(VI) only and (2) pseudo first order disappearance of Cr(VI) from the aqueous phase only, respectively. 相似文献