This study investigates the multiple contamination sources of a coastal Mediterranean aquifer in northeastern Algeria that is bordered by two rivers and neighboring densely populated areas. Hydrogeochemical and isotopic groundwater characterization is carried out, including the analyses of major elements, water stable isotopes δ2H-H2O and δ18O-H2O, and stable isotopes of nitrate δ15N-NO3 and δ18O-NO3, and then integrated into the history of land use over the study area. Groundwater nitrate concentrations ranging from 1.6 to 235 mg/L with a median value of 69 mg/L are evidence of the degradation of groundwater quality induced by anthropogenic sources. The combined of δ15N-NO3 and δ18O-NO3 ratios showed that nitrate in groundwater is attributable to (i) the uncontrolled development of inadequate private sanitation systems over the study area, and (ii) the unsafe application of animal manure to fertilize crops. Very active saltwater intrusion is confirmed by several hydrogeochemical indicators. Interestingly, the intrusion mechanism appears to be more complex than a direct intrusion from the Mediterranean Sea. During the high-water period, saltwater intrusion may also originate from the two rivers bordering the aquifer, via upstream migration of seawater through the river mouths. The heavier ratios in δ2H-H2O and δ18O-H2O of surface water collected from the rivers suggest that water from the Mediterranean Sea is mixing with water in the rivers. Multi-source contamination not only contributes to complex chemical reactions within the aquifer, but also contributes, via the cumulative effect of the various sources, to affecting large parts of the study area. The present study may serve as a warning to the effect that historical land-use practices may exert seriously deleterious impacts on groundwater quality and greatly limit conditions for the sustainable management of Mediterranean coastal areas.

This study investigates the multiple contamination sources of a coastal Mediterranean aquifer in northeastern Algeria that is bordered by two rivers and neighboring densely populated areas. Hydrogeochemical and isotopic groundwater characterization is carried out, including the analyses of major elements, water stable isotopes δ2H-H2O and δ18O-H2O, and stable isotopes of nitrate δ15N-NO3 and δ18O-NO3, and then integrated into the history of land use over the study area. Groundwater nitrate concentrations ranging from 1.6 to 235 mg/L with a median value of 69 mg/L are evidence of the degradation of groundwater quality induced by anthropogenic sources. The combined of δ15N-NO3 and δ18O-NO3 ratios showed that nitrate in groundwater is attributable to (i) the uncontrolled development of inadequate private sanitation systems over the study area, and (ii) the unsafe application of animal manure to fertilize crops. Very active saltwater intrusion is confirmed by several hydrogeochemical indicators. Interestingly, the intrusion mechanism appears to be more complex than a direct intrusion from the Mediterranean Sea. During the high-water period, saltwater intrusion may also originate from the two rivers bordering the aquifer, via upstream migration of seawater through the river mouths. The heavier ratios in δ2H-H2O and δ18O-H2O of surface water collected from the rivers suggest that water from the Mediterranean Sea is mixing with water in the rivers. Multi-source contamination not only contributes to complex chemical reactions within the aquifer, but also contributes, via the cumulative effect of the various sources, to affecting large parts of the study area. The present study may serve as a warning to the effect that historical land-use practices may exert seriously deleterious impacts on groundwater quality and greatly limit conditions for the sustainable management of Mediterranean coastal areas.

This study investigates the multiple contamination sources of a coastal Mediterranean aquifer in northeastern Algeria that is bordered by two rivers and neighboring densely populated areas. Hydrogeochemical and isotopic groundwater characterization is carried out, including the analyses of major elements, water stable isotopes δ2H-H2O and δ18O-H2O, and stable isotopes of nitrate δ15N-NO3 and δ18O-NO3, and then integrated into the history of land use over the study area. Groundwater nitrate concentrations ranging from 1.6 to 235 mg/L with a median value of 69 mg/L are evidence of the degradation of groundwater quality induced by anthropogenic sources. The combined of δ15N-NO3 and δ18O-NO3 ratios showed that nitrate in groundwater is attributable to (i) the uncontrolled development of inadequate private sanitation systems over the study area, and (ii) the unsafe application of animal manure to fertilize crops. Very active saltwater intrusion is confirmed by several hydrogeochemical indicators. Interestingly, the intrusion mechanism appears to be more complex than a direct intrusion from the Mediterranean Sea. During the high-water period, saltwater intrusion may also originate from the two rivers bordering the aquifer, via upstream migration of seawater through the river mouths. The heavier ratios in δ2H-H2O and δ18O-H2O of surface water collected from the rivers suggest that water from the Mediterranean Sea is mixing with water in the rivers. Multi-source contamination not only contributes to complex chemical reactions within the aquifer, but also contributes, via the cumulative effect of the various sources, to affecting large parts of the study area. The present study may serve as a warning to the effect that historical land-use practices may exert seriously deleterious impacts on groundwater quality and greatly limit conditions for the sustainable management of Mediterranean coastal areas.

This study investigates the multiple contamination sources of a coastal Mediterranean aquifer in northeastern Algeria that is bordered by two rivers and neighboring densely populated areas. Hydrogeochemical and isotopic groundwater characterization is carried out, including the analyses of major elements, water stable isotopes δ2H-H2O and δ18O-H2O, and stable isotopes of nitrate δ15N-NO3 and δ18O-NO3, and then integrated into the history of land use over the study area. Groundwater nitrate concentrations ranging from 1.6 to 235 mg/L with a median value of 69 mg/L are evidence of the degradation of groundwater quality induced by anthropogenic sources. The combined of δ15N-NO3 and δ18O-NO3 ratios showed that nitrate in groundwater is attributable to (i) the uncontrolled development of inadequate private sanitation systems over the study area, and (ii) the unsafe application of animal manure to fertilize crops. Very active saltwater intrusion is confirmed by several hydrogeochemical indicators. Interestingly, the intrusion mechanism appears to be more complex than a direct intrusion from the Mediterranean Sea. During the high-water period, saltwater intrusion may also originate from the two rivers bordering the aquifer, via upstream migration of seawater through the river mouths. The heavier ratios in δ2H-H2O and δ18O-H2O of surface water collected from the rivers suggest that water from the Mediterranean Sea is mixing with water in the rivers. Multi-source contamination not only contributes to complex chemical reactions within the aquifer, but also contributes, via the cumulative effect of the various sources, to affecting large parts of the study area. The present study may serve as a warning to the effect that historical land-use practices may exert seriously deleterious impacts on groundwater quality and greatly limit conditions for the sustainable management of Mediterranean coastal areas.

This study investigates the multiple contamination sources of a coastal Mediterranean aquifer in northeastern Algeria that is bordered by two rivers and neighboring densely populated areas. Hydrogeochemical and isotopic groundwater characterization is carried out, including the analyses of major elements, water stable isotopes δ2H-H2O and δ18O-H2O, and stable isotopes of nitrate δ15N-NO3 and δ18O-NO3, and then integrated into the history of land use over the study area. Groundwater nitrate concentrations ranging from 1.6 to 235 mg/L with a median value of 69 mg/L are evidence of the degradation of groundwater quality induced by anthropogenic sources. The combined of δ15N-NO3 and δ18O-NO3 ratios showed that nitrate in groundwater is attributable to (i) the uncontrolled development of inadequate private sanitation systems over the study area, and (ii) the unsafe application of animal manure to fertilize crops. Very active saltwater intrusion is confirmed by several hydrogeochemical indicators. Interestingly, the intrusion mechanism appears to be more complex than a direct intrusion from the Mediterranean Sea. During the high-water period, saltwater intrusion may also originate from the two rivers bordering the aquifer, via upstream migration of seawater through the river mouths. The heavier ratios in δ2H-H2O and δ18O-H2O of surface water collected from the rivers suggest that water from the Mediterranean Sea is mixing with water in the rivers. Multi-source contamination not only contributes to complex chemical reactions within the aquifer, but also contributes, via the cumulative effect of the various sources, to affecting large parts of the study area. The present study may serve as a warning to the effect that historical land-use practices may exert seriously deleterious impacts on groundwater quality and greatly limit conditions for the sustainable management of Mediterranean coastal areas.

This study investigates the multiple contamination sources of a coastal Mediterranean aquifer in northeastern Algeria that is bordered by two rivers and neighboring densely populated areas. Hydrogeochemical and isotopic groundwater characterization is carried out, including the analyses of major elements, water stable isotopes δ2H-H2O and δ18O-H2O, and stable isotopes of nitrate δ15N-NO3 and δ18O-NO3, and then integrated into the history of land use over the study area. Groundwater nitrate concentrations ranging from 1.6 to 235 mg/L with a median value of 69 mg/L are evidence of the degradation of groundwater quality induced by anthropogenic sources. The combined of δ15N-NO3 and δ18O-NO3 ratios showed that nitrate in groundwater is attributable to (i) the uncontrolled development of inadequate private sanitation systems over the study area, and (ii) the unsafe application of animal manure to fertilize crops. Very active saltwater intrusion is confirmed by several hydrogeochemical indicators. Interestingly, the intrusion mechanism appears to be more complex than a direct intrusion from the Mediterranean Sea. During the high-water period, saltwater intrusion may also originate from the two rivers bordering the aquifer, via upstream migration of seawater through the river mouths. The heavier ratios in δ2H-H2O and δ18O-H2O of surface water collected from the rivers suggest that water from the Mediterranean Sea is mixing with water in the rivers. Multi-source contamination not only contributes to complex chemical reactions within the aquifer, but also contributes, via the cumulative effect of the various sources, to affecting large parts of the study area. The present study may serve as a warning to the effect that historical land-use practices may exert seriously deleterious impacts on groundwater quality and greatly limit conditions for the sustainable management of Mediterranean coastal areas.

In this paper, we consider a coupled system of two nonlinearhyperbolic equations with variable-exponents in the damping and sourceterms. Under suitable assumptions on the intial data and the variableexponents, we prove a global existence theorem, using the Stable-setmethod. Then, we establish a decay estimate of the solution energy, byKomornik’s integral approach.

In this paper, we consider a coupled system of two nonlinearhyperbolic equations with variable-exponents in the damping and sourceterms. Under suitable assumptions on the intial data and the variableexponents, we prove a global existence theorem, using the Stable-setmethod. Then, we establish a decay estimate of the solution energy, byKomornik’s integral approach.

In this paper, we present a new technique for constructing a nonstationary wavelet. The key idea relies on the following: for each wavelet level, we solve the Bezout’s equation and we propose a positive solution over the interval [–1, 1]. Using the Bernstein’s polynomials we approximate this proposed positive solution with the intention to perform a spectral factorization.

In this paper, we present a new technique for constructing a nonstationary wavelet. The key idea relies on the following: for each wavelet level, we solve the Bezout’s equation and we propose a positive solution over the interval [–1, 1]. Using the Bernstein’s polynomials we approximate this proposed positive solution with the intention to perform a spectral factorization.

In this paper, we present a new technique for constructing a nonstationary wavelet. The key idea relies on the following: for each wavelet level, we solve the Bezout’s equation and we propose a positive solution over the interval [–1, 1]. Using the Bernstein’s polynomials we approximate this proposed positive solution with the intention to perform a spectral factorization.

In this paper, we consider a nonlinear wave equation with damping and source terms of variable-exponent types. First, we use the stable-set method to prove a global result. Then, by applying an integral inequality due to Komornik, we obtain the stability result.

In this paper, we consider a nonlinear wave equation with damping and source terms of variable-exponent types. First, we use the stable-set method to prove a global result. Then, by applying an integral inequality due to Komornik, we obtain the stability result.

In this paper, we consider a nonlinear wave equation with damping and source terms of variable-exponent types. First, we use the stable-set method to prove a global result. Then, by applying an integral inequality due to Komornik, we obtain the stability result.

The current paper is principally motivated by establishing the global wellposedness to the three-dimensional Boussinesq system with zero diffusivity in thesetting of axisymmetric flows without swirling with v0 ∈ H12(R3) ∩ B˙ 30,1(R3) anddensity ρ0 ∈ L2(R3)∩B˙ 30,1(R3). This respectively enhances the two results recentlyaccomplished in Danchin and Paicu (2008) and Hmidi and Rousset (2010). Ourformalism is inspired, in particular for the first part from Abidi (2008) concerningthe axisymmetric Navier–Stokes equations once v0 ∈ H12(R3) and external forcef ∈ L2 loc(R+; Hβ(R3)), with β > 1 4 . This latter regularity on f which is thedensity in our context is helpless to achieve the global estimates for Boussinesqsystem. This technical defect forces us to deal once again with a similar proof tothat of Abidi (2008) but with f ∈ Lβ loc(R+; L2(R3)) for some β > 4. Second, weexplore the gained regularity on the density by considering it as an external forcein order to apply the study already obtained to the Boussinesq system.

The current paper is principally motivated by establishing the global wellposedness to the three-dimensional Boussinesq system with zero diffusivity in thesetting of axisymmetric flows without swirling with v0 ∈ H12(R3) ∩ B˙ 30,1(R3) anddensity ρ0 ∈ L2(R3)∩B˙ 30,1(R3). This respectively enhances the two results recentlyaccomplished in Danchin and Paicu (2008) and Hmidi and Rousset (2010). Ourformalism is inspired, in particular for the first part from Abidi (2008) concerningthe axisymmetric Navier–Stokes equations once v0 ∈ H12(R3) and external forcef ∈ L2 loc(R+; Hβ(R3)), with β > 1 4 . This latter regularity on f which is thedensity in our context is helpless to achieve the global estimates for Boussinesqsystem. This technical defect forces us to deal once again with a similar proof tothat of Abidi (2008) but with f ∈ Lβ loc(R+; L2(R3)) for some β > 4. Second, weexplore the gained regularity on the density by considering it as an external forcein order to apply the study already obtained to the Boussinesq system.

The contribution of this paper will be focused on the global existence and uniqueness topic in three-dimensional case of the axisymmetric viscous Boussinesq system in critical Lebesgue spaces. We aim at deriving analogous results for the classical two-dimensional and three-dimensional axisymmetric Navier-Stokes equations recently obtained in [19, 20]. Roughly speaking, we show essentially that if the initial data (v0; ρ0) is axisymmetricand (!0; ρ0) belongs to the critical space L1(Ω) ×L1(R3), with !0 is the initialvorticity associated to v0 and Ω = f(r; z) 2 R2 : r > 0g, then the viscousBoussinesq system has a unique global solution.

The contribution of this paper will be focused on the global existence and uniqueness topic in three-dimensional case of the axisymmetric viscous Boussinesq system in critical Lebesgue spaces. We aim at deriving analogous results for the classical two-dimensional and three-dimensional axisymmetric Navier-Stokes equations recently obtained in [19, 20]. Roughly speaking, we show essentially that if the initial data (v0; ρ0) is axisymmetricand (!0; ρ0) belongs to the critical space L1(Ω) ×L1(R3), with !0 is the initialvorticity associated to v0 and Ω = f(r; z) 2 R2 : r > 0g, then the viscousBoussinesq system has a unique global solution.

The contribution of this paper will be focused on the global existence and uniqueness topic in three-dimensional case of the axisymmetric viscous Boussinesq system in critical Lebesgue spaces. We aim at deriving analogous results for the classical two-dimensional and three-dimensional axisymmetric Navier-Stokes equations recently obtained in [19, 20]. Roughly speaking, we show essentially that if the initial data (v0; ρ0) is axisymmetricand (!0; ρ0) belongs to the critical space L1(Ω) ×L1(R3), with !0 is the initialvorticity associated to v0 and Ω = f(r; z) 2 R2 : r > 0g, then the viscousBoussinesq system has a unique global solution.